Publications

Chaczko, Z 2012, 'WSN Clustering Using IC-SVD Algorithms' in Moreno DÃ az, R, Pichler, F & Quesada Arencibia, A (eds), Lecture Notes in Computer Science, Springer Berlin Heidelberg, Las Palmas de Gran Canaria, Spain, pp. 137-145.
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This chapter presents a new biomimetic approach for sensor placement, clustering and data routing in Wireless Sensor Networks that can be deployed and managed in ubiquitous applications such as: security, business, automation, home and healthcare, precision agriculture, ecosystem monitoring and many more. Since hierarchical clustering can reduce the resource usage in sensor networks, we investigate ImmunoComputing and SVD-based algorithms for sensor clustering, routing and management of sensornet resources. The simulation results show that the proposed approach can improve robustness and extend the life-span of network infrastructures.

Chaczko, Z & Resconi, G 2012, 'Application of Morphotronic Theory to Parallel Robots' in Moreno D az, R, Pichler, F & Quesada Arencibia, A (eds), Lecture Notes in Computer Science, Springer Berlin Heidelberg, Las Palmas de Gran Canaria, Spain, pp. 153-160.
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The main aim of this paper is to demonstrate the connection between parallel robotics and electronic circuits using the Morphotronic geometry. Parallel robotic system can be represented by a non Euclidean geometry which metric is the kinetic energy and the metric tensor is the mass metrics in the configuration space of the join angles. We can also remark that for electrical circuit we can have a similar non Euclidean geometry in the space of the currents or voltages. In this way we establish a morphological connection between the mechanical and electrical devises that we denote as Morphotronic. We present examples for the geometry in the kinetic space and example in the natural biological membrane represented by electrical circuits.

Gu, L, Yang, Y, Chen, S & Karmakar, NC 2012, 'Design of High Efficiency Power Amplifier for RFID Readers' in Chipless and Conventional Radio Frequency Identification, IGI Global, pp. 128-144.
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In RFID reader systems, power amplifier plays a critical rule for efficiency enhancement. A high efficiency power amplifier may not only increase the life expectancy of portable RFID devices but also reduce the reliance on heat sinks. Heat sinks usually occupy plenty of space and lead to packing difficulties. A well-designed power amplifier with high efficiency and output power may also increase the reading range of RFID and system reliability, especially for the applications requiring long reading range (e.g. vehicle tagging in complicated traffics) or in a lossy environment (e.g. in sensing in rainy weather). This chapter systematically introduces the typical power amplifiers classified as Class A, AB, B, E, and F. The principles of Class F are emphasized due to its outstanding performance in efficiency enhancement. A practical design example is also presented, and also some recent typical techniques for improving the performances of Class F power amplifier are summarized.

Kale, A, Chaczko, Z & Rudas, I 2012, 'Parallel Robot Vision Using Genetic Algorithm and Object Centroid' in Moreno Diaz, R, Pichler, F & Quesada Arencibia, A (eds), Lecture Notes in Computer Science, Springer Berlin Heidelberg, Las Palmas de Gran Canaria, Spain, pp. 170-178.
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Parallel Robots are playing a very important role in the medical, automotive, food and many manufacturing applications. Due to its high speed and efficient operation, it is gaining an increasing popularity in these application domains. For making the parallel robots more automated and an intelligent a machine vision system with robust performance is needed. Here, a Machine Vision Algorithm based on Genetic Evolutionary principles for object detection in the Delta Parallel Robot based systems is proposed. The solution applies a simple, robust and high speed algorithm to accurately detect objects for the application domain. The Image Acquisition of a robotâs workspace is performed by using a camera mounted on the end-effector of the robot. The system is trained with the object database and with the most significant visual features of every class of objects. Images are assessed periodically for detecting the Region of Interest (ROI) within an image of the robotâs workspace. The ROI is defined as an area in which a presence of object features is detected. The ROI detection is achieved by applying a random sampling of pixels and an assessment of color threshold of every pixel. The color intensity is assumed as one of the features for classification that is based on the training data. After classification process, the Genetic Algorithm is applied to locate the centroid of an object in every class. In a given application class, the Centroid is considered as the most important feature. Knowledge of an approximate location of the Centroid of objects helps to maintain a high speed and reliable pick and place operations of the Delta robot system. The proposed algorithm is tested by detecting presence of electronic components in the workspace. Experimental results show that the suggested approach offers a reliable solution for the Delta robot system.

Resconi, G & Chaczko, Z 2012, 'Mechatronics and the Bond Graph Theory Extended by the Morphotronic Systems' in Moreno Diaz, R, Pichler, F & Quesada Arencibia, A (eds), Lecture Notes in Computer Science, Springer Berlin Heidelberg, Las Palmas de Gran Canaria, Spain, pp. 161-169.
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Mechatronics plays an important role in surgical, automotive, food and industrial applications. To become smarter and more robust, mechatronic systems have to rely on numerous objects and controls that operate in a diverse range of conditions. These controls can exhibit undesirable and coupled behavior. Adjusting the controllers in hardware is difficult and time consuming, often resulting in de-tuning the system below acceptable performance levels. The Morphotronics theory aided by a new approach to the Bond Graph theory represents an improvement to traditional computation models used for the analysis of mechatronic systems. Morphotronics use non-Euclidean geometry for context shaping and defining the projection operators in an ideal network of mechatronic forms.

Yang, Y, Rahim, A & Karmakar, NC 2012, '5.8 GHz Portable Wireless Monitoring System for Sleep Apnea Diagnosis in Wireless Body Sensor Network (WBSN) Using Active RFID and MIMO Technology' in Advanced RFID Systems, Security, and Applications, IGI Global, pp. 264-303.
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Sleep apnea is a severe, potentially life-threatening condition that requires immediate medical attention. In this chapter, a novel wireless sleep apnea monitoring system is proposed to avoid uncomfortable sleep in an unfamiliar sleep laboratory in traditional PSG-based wired monitoring systems. In wireless sleep apnea monitoring system, signal propagation paths may be affected by fading because of reflection, diffraction, energy absorption, shadowing by the body, body movement, and the surrounding environment. To combat the fading effect in WBSN, the MIMO technology is introduced in this chapter. In addition, the presented active RFID based system is composed of two main parts. The first is an on-body sensor system; the second is a reader and base station. In order to minimize the physical size of the on-body sensors and to avoid interference with 2.4 GHz wireless applications, the system is designed to operate in the 5.8 GHz ISM band. Each on-body sensor system consists of a physiological signal detection circuit, an analogue-to-digital convertor (ADC), a microcontroller (MCU), a transceiver, a channel selection bandpass filter (BPF), and a narrow band antenna.

Zeng, C, Jia, W, He, X & Xu, M 2012, 'Recent advances on graph-based image segmentation techniques' in Bai, X, Cheng, J & Hancock, E (eds), Graph Based Methods in Computer Vision Developments and Applications, IGI Global, Hershey, Pennsylvania (USA), pp. 140-154.
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Image segmentation techniques using graph theory has become a thriving research area in computer vision community in recent years. This chapter mainly focuses on the most up-to-date research achievements in graph-based image segmentation published in top journals and conferences in computer vision community. The representative graph-based image segmentation methods included in this chapter are classified into six categories: minimum-cut/maximum-flow model (called graph-cut in some literatures), random walk model, minimum spanning tree model, normalized cut model and isoperimetric graph partitioning. The basic rationales of these models are presented, and the image segmentation methods based on these graph-based models are discussed as the main concern of this chapter. Several performance evaluation methods for image segmentation are given. Some public databases for testing image segmentation algorithms are introduced and the future work on graph-based image segmentation is discussed at the end of this chapter. © 2013, IGI Global.

Cai, Y, Guo, YJ & Bird, TS 2012, 'A Frequency Reconfigurable Printed Yagi-Uda Dipole Antenna for Cognitive Radio Applications', IEEE Transactions on Antennas and Propagation, vol. 60, no. 6, pp. 2905-2912.
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A frequency reconfigurable printed Yagi-Uda antenna is presented for cognitive radio applications. A 46% continuous frequency tuning bandwidth is obtained by loading the driver dipole arms and four directors with varactor diodes. This configuration allows a high-gain and an almost constant end-fire pattern to be maintained while the antenna operating frequency is tuned. A parametric study was undertaken considering the inter-director spacing, director length tapering, and reflector geometry. It was found possible over the band that the front-to-back ratio is > 16 dB, the sidelobe level is < -14 dB and the cross polarization levels in the principal planes are < - 15.5 dB. From 1-dB compression point measurements, the maximum input power of the antenna with the present diodes is limited to 17.6 dBm at 700 MHz. This suggests that reconfigurable antennas which use active components should have an IIP3 specification placed on them. The frequency selective feature of the antenna makes it as an attractive user terminal antenna for fixed point-to-multipoint cognitive radio enabled broadband wireless access. © 2012 IEEE.

Cai, Y, Guo, YJ & Qin, P-Y 2012, 'Frequency Switchable Printed Yagi-Uda Dipole Sub-Array for Base Station Antennas', IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, vol. 60, no. 3, pp. 1639-1642.
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A frequency switchable printed Yagi-Uda dipole sub-array is proposed as an array element for base station antennas. The sub-array consists of four Yagi-Uda dipole elements loaded with PIN diodes. The electrical lengths of the director and driven dipole elements can be changed by controlling the PIN diodes states so that the sub-array can operate in two different frequency bands. The impedance bandwidth (|S11|≤ -10dB) is measured to be 4.9% and 12.9% in the lower (from 2.39 to 2.51 GHz) and higher band (from 3.18 to 3.62 GHz), respectively. The measured gain of the sub-array is 9.2 and 11.9 dBi at 2.44 and 3.4 GHz, respectively. The end-fire fan-beam pattern is obtained across the two operation bands, which makes the antenna element suitable for base station application with frequency reconfigurablity.

Chaczko, Z, Aslanzadeh, S & Kuleff, J 2012, 'The Artificial Immune System Approach for Smart Air-Conditioning Control', International Journal of Electronics and Telecommunications, vol. 58, no. 2, pp. 193-199.
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The Artificial Immune System Approach for Smart Air-Conditioning ControlBiologically inspired computing that looks to nature and biology for inspiration is a revolutionary change to our thinking about solving complex computational problems. It looks into nature and biology for inspiration rather than conventional approaches. The Human Immune System with its complex structure and the capability of performing pattern recognition, self-learning, immune-memory, generation of diversity, noise tolerance, variability, distributed detection and optimisation - is one area that has been of strong interest and inspiration for the last decade. An air conditioning system is one example where immune principles can be applied. This paper describes new computational technique called Artificial Immune System that is based on immune principles and refined for solving engineering problems. The presented system solution applies AIS algorithms to monitor environmental variables in order to determine how best to reach the desired temperature, learn usage patterns and predict usage needs. The aim of this paper is to explore the AIS-based artificial intelligence approach and its impact on energy efficiency. It will examine, if AIS algorithms can be integrated within a Smart Air Conditioning System as well as analyse the impact of such a solution.

Chaczko, Z, Aslanzadeh, S, Jiang, F & Klempous, R 2012, 'The Implementation of 3TZ Model of Software Development', International Journal of Electronics and Telecommunications, vol. 58, no. 4, pp. 433-439.
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Abstract This paper presents the concepts and explores issues related to the 3 Time Zones (3TZ) model of software development in global workspace environment. The 3TZ model itself seeks to take advantages of differences in time zones between places around the world. By engaging software development teams in different regions separated by 8 hours each, it is possible for their combined working hours to cover the whole 24 hours period. Thus, while they each work their normal 8 hour days, together they are able to achieve in 1 day what a single team would achieve in 3 days. They are able to achieve this by passing on their work from one team to the next as one finishes their workday and the next team starts their workday. The 3TZ model of software development revolves around the employment of a software development team distributed in at least 3 different locations around the world in 3 different time zones. If work was passed on from one team to the next and adjacent teams were separated by 8 hours, then 24 hours continuous collaborative software development could be achieved. Though this poses many challenges, when dealt with there is great potential for software to be developed much faster than is possible for a single, collocated development team. In the global economy, we have seen a decrease in the barriers towards communication across the globe along with an increase of service availability to support this communication. Software development is one of the disciplines that is capable of effectively utilizing and benefiting from global collaboration prospect lent by ever increasing capability of information and communication technology. 24 hours continuous development is ideal for application towards tasks that have hard deadlines or require work completed as soon as possible. This article will mainly focus on introducing 24/7 global models that can be applied in cloud environment used in three diffe...

Chaczko, Z, Chiu, C, Aslanzadeh, S & Dune, T 2012, 'Sensor-Actor Network Solution for Scalable Ad-hoc Sensor Networks', International Journal of Electronics and Telecommunications, vol. 58, no. 1, pp. 55-62.
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Sensor-Actor Network Solution for Scalable Ad-hoc Sensor NetworksArchitects of ad-hoc wireless Sensor-Actor Networks (SANETS) face various problems and challenges. The main limitations relate to aspects such as the number of sensor nodes involved, low bandwidth, management of resources and issues related to energy management. In order for these networks to be functionally proficient, the underlying software system must be able to effectively handle unreliable and dynamic distributed communication, power constraints of wireless devices, failure of hardware devices in hostile environments and the remote allocation of distributed processing tasks throughout the wireless network. The solution must be solved in a highly scalable manner. This paper provides the requirements analysis and presents the design of a software system middleware that provides a scalable solution for ad-hoc sensor network infrastructure made of both stationary and mobile sensors and actuators.

Chaczko, Z, Resconi, G, Chiu, C & Aslanzadeh, S 2012, 'N-Body Potential Interaction as a Cost Function in the Elastic Model for SANET Cloud Computing', International Journal of Electronics and Telecommunications, vol. 58, no. 1, pp. 63-70.
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N-Body Potential Interaction as a Cost Function in the Elastic Model for SANET Cloud ComputingGiven a connection graph of entities that send and receive a flow of data controlled by effort and given the parameters, the metric tensor is computed that is in the elastic relational flow to effort. The metric tensor can be represented by the Hessian of the interaction potential. Now the interaction potential or cost function can be among two entities: 3 entities or ‘N’ entities and can be separated into two main parts. The first part is the repulsion potential the entities move further from the others to obtain minimum cost, the second part is the attraction potential for which the entities move near to others to obtain the minimum cost. For Pauli's model [1], the attraction potential is a functional set of parameters given from the environment (all the elements that have an influence in the module can be the attraction of one entity to another). Now the cost function can be created in a space of macro-variables or macro-states that is less of all possible variables. Any macro-variable collect a set of micro-variables or microstates. Now from the hessian of the macro-variables, the Hessian is computed of the micro-variables in the singular points as stable or unstable only by matrix calculus without any analytical computation - possible when the macro-states are distant among entities. Trivially, the same method can be obtained by a general definition of the macro-variable or macro-states and micro-states or variables. As cloud computing for Sensor-Actor Networks (SANETS) is based on the bonding concept for complex interrelated systems; the bond valence or couple corresponds to the minimum of the interaction potential V and in the SANET cloud as the minimum cost.

Chen, X, Yang, J, Wu, Q, Zhao, J & He, X 2012, 'Directional high-pass filter for blurry image analysis', Signal Processing: Image Communication, vol. 27, no. 7, pp. 760-771.
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High-frequency energy distributions are important characteristics of blurry images. In this paper, directional high-pass filters are proposed to analyze blurry images. Firstly, we show that the proposed directional high-pass filters can effectively estimate the motion direction of motion blurred images. A closed-form solution for motion direction estimation is derived. It achieves a higher estimation accuracy and is also faster than previous methods. Secondly, the paper suggests two important applications of the directional high-frequency energy analysis. It can be employed to identify out-of-focus blur and motion blur, and to detect motion blurred regions in observed images. Experiments on both synthetic and real blurred images are conducted. Encouraging results demonstrate the efficacy of the proposed methods. © 2012 Elsevier B.V. All rights reserved.

Cheng, P, Gui, L, Rui, Y, Guo, YJ, Huang, X & Zhang, W 2012, 'Compressed Sensing Based Channel Estimation for Two-Way Relay Networks', IEEE Wireless Communications Letters, vol. 1, no. 3, pp. 201-204.
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In this letter, a novel channel estimation scheme based on compressed sensing (CS) theory is proposed for two-way relay networks (TWRN) in sparse frequency-selective fading channels. Unlike point-to-point systems, applying CS theory to sparse channel estimation in TWRN is much more challenging since the equivalent channels (terminal-relay-terminal) may be no longer sparse due to the linear convolutional operation. To solve this problem, instead of directly estimating the equivalent channels, a linear precoding based method is designed to firstly separate the individual channels between the terminals and the relay from the equivalent channels. CS theory is then applied to the time-domain channel estimation with much smaller number of pilot symbols. This scheme enables accurate channel estimation for TWRN with significant overhead reduction. Extensive numerical results are provided to substantiate the effectiveness of the proposed method. © 2012 IEEE.

Du, J, Macfarlane, JC, Pegrum, CM, Zhang, T, Cai, Y & Guo, YJ 2012, 'A self-pumped high-temperature superconducting Josephson mixer: Modelling and measurement', Journal of Applied Physics, vol. 111, no. 5, pp. 053910-053910.
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We have recently developed a high-temperature superconducting (HTS) Josephson self-pumped mixer with an on-chip heterodyne local oscillator. The device is based on HTS step-edge junction technology and a “resistive-superconducting quantum interference device” (RSQUID) configuration. The heterodyne local oscillator and mixer output are frequency-tunable from below 10 MHz to 5 GHz by a control current. The performance of the autonomous Josephson mixer–local oscillator has been experimentally evaluated in terms of the current-voltage characteristics, intermediate frequency (IF)-tunable bandwidth, operation range, linearity, bias current, and temperature dependence of the IF output (or mixer conversion efficiency). We find the results are in good overall agreement with numerical simulation.

Du, J, Macfarlane, JC, Zhang, T, Cai, Y & Guo, YJ 2012, 'Self-pumped HTS Josephson heterodyne tunable mixer', Superconductor Science and Technology, vol. 25, no. 2, pp. 025019-025019.
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Experimental evaluation of a high-temperature superconducting Josephson heterodyne mixer based on a resistive-SQUID configuration is reported. The device consists of two YBa 2Cu 3O 7-x step-edge Josephson junctions connected via a small resistor in an otherwise superconducting loop. It has been previously shown to generate a heterodyne oscillation, which is frequency-tunable by a control current through the resistor. Under certain conditions, this device can operate as a frequency-tunable heterodyne mixer (down-converter) in the presence of an RF signal. In this paper, we describe the operation of the autonomous Josephson mixerlocal oscillator device and present the experimental results on the mixer performances in terms of the junction currentvoltage characteristics, the frequency tunability, linearity, and dynamic range as well as their temperature dependence for signal frequencies from 1 to 5GHz. © 2012 IOP Publishing Ltd.

Du, J, Zhang, T, Macfarlane, JC, Guo, YJ & Sun, XW 2012, 'Monolithic high-temperature superconducting heterodyne Josephson frequency down-converter', Applied Physics Letters, vol. 100, no. 26, pp. 262604-262604.
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A monolithic microwave integrated circuit (MMIC) frequency down-converter based on a compact high-Tc superconducting (HTS) device is demonstrated. The on-chip integrated HTS down-converter consists of a 7–9 GHz bandpass filter for RF input, a lowpass filter for intermediate frequency output, and a self-pumped Josephson heterodyne mixer. All the above passive and active components are fabricated on a single 10 mm × 20 mm chip of YBa2Cu3O7−x film on MgO substrate. Characterization of this MMIC HTS down-converter in terms of frequency response, conversion gain, frequency-tuneability, bias dependence, dynamic range, linearity, and intrinsic noise are presented in this paper.

Foroughi, J, Kimiaghalam, B, Ghorbani, SR, Safaei, F & Abolhasan, M 2012, 'Effect of conducting polypyrrole on the transport properties of carbon nanotube yarn', THIN SOLID FILMS, vol. 520, no. 24, pp. 7049-7053.
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Experiments were conducted to measure the electrical conductivity in three types of pristine and carbon nanotube-polypyrrole (CNT-PPy) composite yarns and its dependence on over a wide temperature range. The experimental results fit well with the analyti

Garcia-Vigueras, M, Gomez-Tornero, JL, Goussetis, G, Weily, AR & Guo, YJ 2012, 'Efficient Synthesis of 1-D Fabry–Perot Antennas With Low Sidelobe Levels', IEEE Antennas and Wireless Propagation Letters, vol. 11, pp. 869-872.
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A novel technique for the efficient synthesis of one-dimensional (1-D) Fabry-Perot leaky-wave antennas with low sidelobe levels is described. It is based on the study of the reflection characteristics presented by the two periodic surfaces that form the cavity. The synthesis technique avoids the search for modal solutions in the complex plane, which is typically needed to characterize the dispersion of the leaky modes associated with the antenna geometry. Instead, it involves the solution of two simple equations, so that the desired aperture distribution (amplitude and phase) can be directly synthesized. Numerical and experimental results show that the method can be used to efficiently synthesize 1-D Fabry-Perot low sidelobe leaky-wave antennas for any desired scanning angle. © 2002-2011 IEEE.

Ge, Y, Esselle, KP & Bird, TS 2012, 'The Use of Simple Thin Partially Reflective Surfaces With Positive Reflection Phase Gradients to Design Wideband, Low-Profile EBG Resonator Antennas', IEEE Transactions on Antennas and Propagation, vol. 60, no. 2, pp. 743-750.
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Partially reflecting surfaces (PRS) with positive reflection phase gradients are investigated for the design of wideband, low-profile electromagnetic band gap (EBG) resonator antennas. Thin single-dielectric-slab PRSs with printed patterns on both sides are proposed to minimize the PRS thickness and to simplify fabrication. Three such surfaces, each with printed dipoles on both sides, have been designed to obtain different positive reflection phase gradients and reflection magnitude levels in the operating frequency bands. These surfaces, and the EBG resonator antennas formed from them, are analyzed theoretically and experimentally to highlight the design compromises involved and to reveal the relationships between the antenna peak gain, gain bandwidth, the reflection profile (i.e., positive phase gradient and magnitude) of the surface and the relative dimensions of dipoles. A small feed antenna, designed to operate in the cavity field environment, provides good impedance matching (|S 11| < -10 dB) across the operating frequency bands of all three EBG resonator antennas. Experimental results confirm the wideband performance of a simple, low-profile EBG resonator antenna. Its PRS thickness is only 1.6 mm, effective bandwidth is 12.6%, measured peak gain is 16.2 dBi at 11.5 GHz and 3 dB gain bandwidth is 15.7%. © 2011 IEEE.

Guo, YJ, Xiaojing Huang & Dyadyuk, V 2012, 'A Hybrid Adaptive Antenna Array for Long-Range mm-Wave Communications [Antenna Applications Corner]', IEEE Antennas and Propagation Magazine, vol. 54, no. 2, pp. 271-282.
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Owing to the availability of wide (GHz) bandwidth at mm-wave frequencies, there is growing interest in high-speed mm-wave communications systems. However, the limited physical size and volume of the antenna and RF system do pose several major challenges. This article presents CSIRO's research on hybrid adaptive antenna arrays and associated digital-beamforming algorithms for achieving high-speed long-range communications in the millimeter-wave frequency bands. The hybrid antenna array consists of a number of analog subarrays, followed by a digital beamformer. Two subarray configurations - the interleaved subarray and the side-by-side subarray - are described. The adaptive angle-of-arrival (AoA) estimation and beamforming algorithms in both the time and frequency domains are discussed. The performance of the system was evaluated by simulations. An early stage proof-of-concept adaptive antenna array prototype in the 71 to 76 GHz E band is presented. © 2011 IEEE.

Guzman-Quiros, R, Gomez-Tornero, JL, Weily, AR & Guo, YJ 2012, 'Electronic Full-Space Scanning With 1-D Fabry–Pérot LWA Using Electromagnetic Band-Gap', IEEE Antennas and Wireless Propagation Letters, vol. 11, pp. 1426-1429.
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A novel mechanism to obtain full-space electronic scanning from a half-space scanning one-dimensional (1-D) Fabry-Pérot (FP) leaky-wave antenna (LWA) is proposed and experimentally demonstrated in this letter. By using a central feed that divides the structure into two independently controlled leaky lines, one each side, and making use of the electromagnetic band-gap (EBG) region of the FP resonator, the antenna can be electronically tuned to operate in three different regimes: backward scanning, forward scanning, and broadside radiation. Leaky-mode dispersion theory and experimental results of a fabricated prototype demonstrate a continuous electronic scanning from-25° to +25° at 5.5 GHz. © 2011 IEEE.

Guzman-Quiros, R, Gomez-Tornero, JL, Weily, AR & Guo, YJ 2012, 'Electronically Steerable 1-D Fabry-Perot Leaky-Wave Antenna Employing a Tunable High Impedance Surface', IEEE Transactions on Antennas and Propagation, vol. 60, no. 11, pp. 5046-5055.
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© 2012 IEEE. A novel fixed-frequency electronically-steerable one-dimensional (1-D) leaky-wave antenna is presented. The antenna is based on a parallel-plate waveguide loaded with a planar partially reflective surface and a tunable high impedance surface (HIS), which creates a 1-D Fabry-Perot leaky-waveguide. The tunable HIS consists of printed patches loaded with varactor diodes that allow the electronic tuning of the cavity resonance condition. Using a simple Transverse Equivalent Network, it is theoretically shown how the variation of the varactors’ junction capacitance allows the scanning of the antenna pointing angle from broadside towards the endfire direction at a fixed frequency. Experimental results of an antenna prototype operating at 5.6 GHz are reported, demonstrating that the new reconfigurable leaky-wave antenna can provide electronic beam scanning in an angular range from 9° to 30°.

Haidar, G, Ghassempour, S & Braun, R 2012, 'Nature-Inspired Routing Algorithm for Wireless Sensor Networks', Australian Journal of Electrical and Electronics Engineering, vol. 9, no. 3, pp. 327-334.
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Haidar, G, Ghassempour, S & Braun, R 2012, 'Nature-inspired routing algorithm for wireless sensor networks', Australian Journal of Electrical & Electronics Engineering, vol. 9, no. 3, pp. 327-334.
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This paper reports on a project to investigate, build upon and test a relatively new routing algorithm for wireless sensor networks. The algorithm is based on the behaviour of ants in nature. It attempts to address the need for an energy-efficient routing algorithm for wireless sensor networks. This journal article briefly discusses the algorithm's design, including the algorithm outline and relevant data structures and formulae. The article proceeds to discuss the testing procedure and test results for the algorithm. Finally, a conclusion summarising findings and recommendations for future work is included. © Institution of Engineers Australia 2012.

Han, L, Fu, C, Zou, D, Lee, C & Jia, W 2012, 'Task-based behavior detection of illegal codes', Mathematical and Computer Modelling, vol. 55, no. 1-2, pp. 80-86.
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Detecting unseen illegal codes is always a challenging task. As the main action to deal with this problem, the behavior detection is unsatisfactory in both effectiveness and efficiency. This paper proposes task-based behavior detection (TBBD) which detects new illegal codes based on the user's task instead of only on the software behavior. First, the paper proposes three prerequisites of TBBD and four judgment rules, i.e., resource abnormal rule, relation abnormal rule, space abnormal rule and time abnormal rule. Then, by analyzing the effectiveness and comparison of the four judgment rules, we present an explicit judgment process of TBBD. Finally, the paper carries on the experiments. The test result verifies the validity and feasibility of TBBD. © 2011 Elsevier Ltd.

Hedley, M & Zhang, J 2012, 'Accurate Wireless Localization in Sports', Computer, vol. 45, no. 10, pp. 64-70.
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The wireless ad hoc system for positioning (WASP) provides high accuracy and high update rates when used for performance monitoring in elite sports training, where using real-time location and physiological information helps improve athletic performance. © 2012 IEEE.

Huang, X, Guo, Y, Zhang, A & Dyadyuk, V 2012, 'A multi-gigabit microwave backhaul', IEEE Communications Magazine, vol. 50, no. 3, pp. 122-129.
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The rapid growth of multimedia broadband wireless services has placed huge pressure on the backhaul infrastructure. As cost-effective alternatives to fibre backhauls, high speed microwave backhauls provide a number of significant benefits, especially for bringing broadband services to rural and regional areas. This article addresses the challenges to wireless backhauls and presents a multi-gigabit microwave backhaul system, called Ngara backhaul, which is being developed at the Commonwealth Scientific and Industrial Research Organisation (CSIRO), Australia. The various innovative aspects of the Ngara backhaul system including spectrum aggregation, peak-toaverage power ratio reduction, out-of-band emission cancellation, and sample rate conversion, are reported. © 2012 IEEE.

Huang, X, Guo, YJ & Zhang, JA 2012, 'Sample Rate Conversion Using B-Spline Interpolation for OFDM Based Software Defined Radios', IEEE Transactions on Communications, vol. 60, no. 8, pp. 2113-2122.
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This paper proposes arbitrary ratio sample rate conversion (SRC) architectures and a simpler B-spline interpolation algorithm for orthogonal frequency division multiplexing (OFDM) based software defined radios (SDRs) with multiband and multi-channel capabilities. Different from conventional standalone digital front-end designs for SDRs, the proposed SRC architectures combine the B-spline interpolation with OFDM modulation and equalization for OFDM transmitter and receiver respectively. With this combined design, the passband droop introduced by the B-spline interpolation can be more efficiently compensated using frequency-domain pre-distortion, instead of conventional time-domain pre-filtering, and hence an overall system complexity reduction is achieved. A novel multi-period B-spline interpolation and re-sampling structure is then constructed, and an interpolation algorithm with lower implementation complexity than that of the conventional Farrow structure is further developed. The SRC performance is also analysed by deriving the signal-to-peak distortion ratio formulas which can be used as design tools for determining the required orders of B-splines in the OFDM transmitter and receiver respectively. Finally, SRC examples used in a high-speed multiband multi-channel microwave backhaul system are given and compared with conventional polyphase filterbank interpolation to demonstrate the practicality and performance of the proposed SRC architectures and interpolation algorithm. © 1972-2012 IEEE.

Iji, A, Zhu, X & Heimlich, M 2012, 'High gain/power quotient variable‐gain wideband low‐noise amplifier for capsule endoscopy application', Microwave and Optical Technology Letters, vol. 54, no. 11, pp. 2563-2565.
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AbstractAn implantable high gain/power quotient variable‐gain wideband low‐noise amplifier (LNA) suitable for capsule endoscopy application is implemented in a 0.25 μm silicon‐on‐insulator CMOS process. With a current‐reused topology and wideband matching network, the presented LNA exhibits peak gain of 13.8 dB, 2.3 dB noise figure, more than 1 GHz bandwidth and 5 dB gain tuning range with good input and output impedance matching. The LNA consumes only 1.8 mW DC power from a supply voltage of 1.5 V. An excellent average gain/power quotient of 6.8 dB/mW is achieved. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2563–2565, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27111

Kegen Yu & Dutkiewicz, E 2012, 'Geometry and Motion-Based Positioning Algorithms for Mobile Tracking in NLOS Environments', IEEE Transactions on Mobile Computing, vol. 11, no. 2, pp. 254-263.
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Kusakunniran, W, Qiang Wu, Jian Zhang & Hongdong Li 2012, 'Gait Recognition Across Various Walking Speeds Using Higher Order Shape Configuration Based on a Differential Composition Model', IEEE Transactions on Systems, Man, and Cybernetics, Part B (Cybernetics), vol. 42, no. 6, pp. 1654-1668.
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Gait has been known as an effective biometric feature to identify a person at a distance. However, variation of walking speeds may lead to significant changes to human walking patterns. It causes many difficulties for gait recognition. A comprehensive analysis has been carried out in this paper to identify such effects. Based on the analysis, Procrustes shape analysis is adopted for gait signature description and relevant similarity measurement. To tackle the challenges raised by speed change, this paper proposes a higher order shape configuration for gait shape description, which deliberately conserves discriminative information in the gait signatures and is still able to tolerate the varying walking speed. Instead of simply measuring the similarity between two gaits by treating them as two unified objects, a differential composition model (DCM) is constructed. The DCM differentiates the different effects caused by walking speed changes on various human body parts. In the meantime, it also balances well the different discriminabilities of each body part on the overall gait similarity measurements. In this model, the Fisher discriminant ratio is adopted to calculate weights for each body part. Comprehensive experiments based on widely adopted gait databases demonstrate that our proposed method is efficient for cross-speed gait recognition and outperforms other state-of-the-art methods. © 1996-2012 IEEE.

Kusakunniran, W, Wu, Q, Zhang, J & Li, H 2012, 'Cross-view and multi-view gait recognitions based on view transformation model using multi-layer perceptron', PATTERN RECOGNITION LETTERS, vol. 33, no. 7, pp. 882-889.
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Gait has been shown to be an efficient biometric feature for human identification at a distance. However, performance of gait recognition can be affected by view variation. This leads to a consequent difficulty of cross-view gait recognition. A novel method is proposed to solve the above difficulty by using view transformation model (VTM). VTM is constructed based on regression processes by adopting multi-layer perceptron (MLP) as a regression tool. VTM estimates gait feature from one view using a well selected region of interest (ROI) on gait feature from another view. Thus, trained VTMs can normalize gait features from across views into the same view before gait similarity is measured. Moreover, this paper proposes a new multi-view gait recognition which estimates gait feature on one view using selected gait features from several other views. Extensive experimental results demonstrate that the proposed method significantly outperforms other baseline methods in literature for both cross-view and multi-view gait recognitions. In our experiments, particularly, average accuracies of 99%, 98% and 93% are achieved for multiple views gait recognition by using 5 cameras, 4 cameras and 3 cameras respectively. © 2011 Elsevier B.V. All rights reserved.

Kusakunniran, W, Wu, Q, Zhang, J & Li, H 2012, 'Gait Recognition Under Various Viewing Angles Based on Correlated Motion Regression', IEEE Transactions on Circuits and Systems for Video Technology, vol. 22, no. 6, pp. 966-980.
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It is well recognized that gait is an important biometric feature to identify a person at a distance, e.g., in video surveillance application. However, in reality, change of viewing angle causes significant challenge for gait recognition. A novel approach using regression-based view transformation model (VTM) is proposed to address this challenge. Gait features from across views can be normalized into a common view using learned VTM(s). In principle, a VTM is used to transform gait feature from one viewing angle (source) into another viewing angle (target). It consists of multiple regression processes to explore correlated walking motions, which are encoded in gait features, between source and target views. In the learning processes, sparse regression based on the elastic net is adopted as the regression function, which is free from the problem of overfitting and results in more stable regression models for VTM construction. Based on widely adopted gait database, experimental results show that the proposed method significantly improves upon existing VTM-based methods and outperforms most other baseline methods reported in the literature. Several practical scenarios of applying the proposed method for gait recognition under various views are also discussed in this paper. © 2012 IEEE.

Luo, L, Zhang, JA & Davis, LM 2012, 'Space-Time Block Code and Spatial Multiplexing Design for Quadrature-OFDMA Systems', IEEE Transactions on Communications, vol. 60, no. 10, pp. 3133-3142.
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To alleviate the high peak-to-average power ratio (PAPR), high complexity in user terminal and sensitivity to carrier frequency offset (CFO) problems in current orthogonal frequency division multiple access (OFDMA) systems, a Quadrature OFDM (Q-OFDMA) system has been recently proposed in the single-input single-output environment. In this paper we study the realization of multi-input multi-output (MIMO) diversity-and multiplexing-oriented methods for Q-OFDMA systems. An Alamouti-like space-time block code (STBC) and simple detection for spatial multiplexing (SM) for Q-OFDMA systems are constructed, both zero forcing (ZF) and minimum mean square error (MMSE) equalizers are investigated. The proposed STBC is a full diversity scheme, which encodes in intermediate domain and decodes in frequency domain. Analytical and empirical results demonstrate that the Q-OFDMA systems can be implemented flexibly and efficiently in a MIMO framework, and the proposed scheme can be easily applied in OFDMA and Single-Carrier Frequency Division Multiple Access (SC-FDMA) by adjusting the parameters of Q-OFDMA. © 2012 IEEE.

Masihpour, M, Abolhasan, M & Franklin, DR 2012, 'NFMIC Cooperative Communication Methods for Body Area Networks.', J. Networks, vol. 7, no. 9, pp. 1431-1440.
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To achieve higher data rate or to extend the coverage range of a wireless communication system, cooperative relay has been seen as a promising solution. This concept has been integrated in many traditional wireless communication networks. However, it has not been extensively examined for near field magnetic induction communication (NFMIC) systems. This paper aims to apply cooperative relay to NFMIC in a sense that is applicable to body area networking, since NFMIC is stated to be a suitable physical layer for body area networks. We have shown that using idle NFMIC nodes as relaying terminals, the system performance will be enhanced, as compared to a point to point communication system. In this context we have proposed three relaying methods to enhance the data rate and the received signal power in a personal area network. The relaying strategies are denoted as MI-Relay, MAMI Relay1 and MAMI Relay2. In this paper, using theoretical studies and simulation results, we have compared the performance of the three strategies and we have shown that higher data rates can be achieved through MAMI Relay1. However, we have discussed that the separation distance between relaying nodes and the source or destination can be a key factor for relay node selection.

Nguyen, DN & Krunz, M 2012, 'Price-Based Joint Beamforming and Spectrum Management in Multi-Antenna Cognitive Radio Networks', IEEE Journal on Selected Areas in Communications, vol. 30, no. 11, pp. 2295-2305.
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We consider the problem of maximizing the throughput of a multi-antenna cognitive radio (CR) network. With spatial multiplexing over each frequency band, a multi-antenna CR node controls its antenna radiation directions and allocates power for each data stream by appropriately adjusting its precoding matrix. Our objective is to design a set of precoding matrices (one per band) at each CR node so that power and spectrum are optimally allocated for the node and its interference is steered away from unintended receivers. The problem is non-convex, with the number of variables growing quadratically with the number of antenna elements. To tackle it, we translate it into a noncooperative game. We derive an optimal pricing policy for each node, which adapts to the node's neighboring conditions and drives the game to a Nash-Equilibrium (NE). The network throughput under this NE equals to that of a locally optimal solution of the non-convex centralized problem. To find the set of precoding matrices at each node (best response), we develop a low-complexity distributed algorithm by exploiting the strong duality of the convex per-user optimization problem. The number of variables in the distributed algorithm is independent of the number of antenna elements. A centralized (cooperative) algorithm is also developed. Simulations show that the network throughput under the distributed algorithm rapidly converges to that of the centralized one. Finally, we develop a MAC protocol that implements our resource allocation and beamforming scheme. Extensive simulations show that the proposed protocol dramatically improves the network throughput and reduces power consumption. © 1983-2012 IEEE.

Ni, W, Collings, IB & Liu, RP 2012, 'Relay Handover and Link Adaptation Design for Fixed Relays in IMT-Advanced Using a New Markov Chain Model', IEEE Transactions on Vehicular Technology, vol. 61, no. 4, pp. 1839-1853.
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Fixed relay networks will be an integrated component of future International Mobile Telecommunications (IMT)-Advanced. In this paper, we propose a new approach to relay handover and link adaptation. Our approach is built on a new Markov chain model (MCM) that comprehensively characterizes different relay protocols and quantifies their quality-of-service (QoS) measures, such as packet drop rate and latency, and spectral efficiency. Our relay handover and link adaptation scheme combats channel fluctuations while satisfying QoS requirements. It also accommodates multiple relay stations, supports multiplexing and diversity, and copes with mutually related and time-dependent transmissions. Analytical results, which were validated by simulations, show that our scheme can reduce the packet loss by up to three orders of magnitude. It also decreases the packet delay by up to 18% and improves the throughput by up to 10%. © 2012 IEEE.

Parr, G, Hailes, S, How, JP, McGeehan, J & Guo, YJ 2012, 'Guest Editorial: Communications Challenges and Dynamics for Unmanned Autonomous Vehicles', IEEE Journal on Selected Areas in Communications, vol. 30, no. 5, pp. 849-851.
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Peng, Y, Xu, M, Ni, Z, Jin, JS & Luo, S 2012, 'Combining Front Vehicle Detection with 3D Pose Estimation for a Better Driver Assistance', International Journal of Advanced Robotic Systems, vol. 9, no. 3, pp. 93-93.
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Driver assistant systems enhance traffic safety and efficiency. The accurate 3D pose of a front vehicle can help a driver to make the right decision on the road. We propose a novel real-time system to estimate the 3D pose of the front vehicle. This system consists of two parallel threads: vehicle rear tracking and mapping. The vehicle rear is first identified in the video captured by an onboard camera, after license plate localization and foreground extraction. The 3D pose estimation technique is then employed with respect to the extracted vehicle rear. Most current 3D pose estimation techniques need prior models or a stereo initialization with user cooperation. It is extremely difficult to obtain prior models due to the varying appearance of vehicles' rears. Moreover, it is unsafe to ask for drivers' cooperation when a vehicle is running. In our system, two initial keyframes for stereo algorithms are automatically extracted by vehicle rear detection and tracking. Map points are defined as a collection of point features extracted from the vehicle's rear with their 3D information. These map points are inferences that relate the 2D features detected in following vehicles' rears with the 3D world. The relative 3D pose of the onboard camera to the front vehicle rear is then estimated through matching the map points with point features detected on the front vehicle rear. We demonstrate the capabilities of our system by testing on real-time and synthesized videos. In order to make the experimental analysis visible, we demonstrated an estimated 3D pose through augmented reality, which needs accurate and real-time 3D pose estimation.

Qin, P-Y, Guo, YJ, Weily, AR & Liang, C-H 2012, 'A Pattern Reconfigurable U-Slot Antenna and Its Applications in MIMO Systems', IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, vol. 60, no. 2, pp. 516-528.
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A new compact pattern reconfigurable U-slot antenna is presented. The antenna consists of a U-slot patch and eight shorting posts. Each edge of the square patch is connected to two shorting posts via PIN diodes. By switching between the different states of the PIN diodes, the proposed antenna can operate in either monopolar patch or normal patch mode in similar frequency ranges. Therefore, its radiation pattern can be switched between conical and boresight patterns electrically. In addition, the plane with the maximum power level of the conical pattern can be changed between two orthogonal planes. Owing to a novel design of the switch geometry, the antenna does not need dc bias lines. The measured overlapping impedance bandwidth (|S11| <; -10 dB) of the two modes is 6.6% with a center frequency of 5.32 GHz. The measured radiation patterns agree well with simulated results. The antennas are incorporated in a 2 × 2 multiple-input-multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) system to demonstrate the improvement in system capacity. In the real-time MIMO-OFDM channel measurement, it is shown that compared to omnidirectional antennas, the pattern reconfigurable antennas can enhance the system capacity, with 17% improvement in a line-of-sight (LOS) scenario and 12% in a non-LOS (NLOS) scenario at a signal-to-noise ratio (SNR) of 10 dB.

Ridoux, J, Veitch, D & Broomhead, T 2012, 'The Case for Feed-Forward Clock Synchronization', IEEE/ACM Transactions on Networking, vol. 20, no. 1, pp. 231-242.
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Variable latencies due to communication delays or system noise is the central challenge faced by time-keeping algorithms when synchronizing over the network. Using extensive experiments, we explore the robustness of synchronization in the face of both normal and extreme latency variability and compare the feedback approaches of ntpd and ptpd (a software implementation of IEEE-1588) to the feed-forward approach of the RADclock and advocate for the benefits of a feed-forward approach. Noting the current lack of kernel support, we present extensions to existing mechanisms in the Linux and FreeBSD kernels giving full access to all available raw counters, and then evaluate the TSC, HPET, and ACPI counters' suitability as hardware timing sources. We demonstrate how the RADclock achieves the same microsecond accuracy with each counter.

Sheng Ye, Xianling Liang, Wenzhi Wang, Ronghong Jin, Junping Geng, Bird, TS & Guo, YJ 2012, 'High-Gain Planar Antenna Arrays for Mobile Satellite Communications [Antenna Applications Corner]', IEEE Antennas and Propagation Magazine, vol. 54, no. 6, pp. 256-268.
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Two large and low-profile panel antenna arrays, used as receiving and transmitting antennas for mobile satellite communications, are described. The receiving and transmitting arrays have overall dimensions of 120 cm × 20.7 cm × 1.3cm and 107.5 cm × 20.4 cm × 1.7 cm, respectively. They exhibit high gains and adequate efficiencies, due to integrated array designs. For the receiving panel array, a method using a number of high-efficiency subarrays, combined with a novel active integrated global feed network, is proposed. For the transmitting panel array, a number of high-efficiency subarrays, together with a novel compact waveguide feed network, is employed. Based on the above techniques, two large panel antenna arrays were successfully developed. We present the detailed designs of the subarrays, the passive and active feed networks, and the vertical transitions. Simulated and experimental results showed that the designed receiving and transmitting panel arrays achieved measured gains and efficiencies of 34.1 dBi and 48.2%, and 33.5 dBi and 36.3%, respectively, in each band. This indicated that the proposed antenna panels are good candidates for future satellite communications applications. © 2011 IEEE.

Sun, X-C, Cui, H-Y, Liu, R-P, Chen, J-Y & Liu, Y-J 2012, 'Modeling deterministic echo state network with loop reservoir', Journal of Zhejiang University SCIENCE C, vol. 13, no. 9, pp. 689-701.
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Echo state network (ESN), which efficiently models nonlinear dynamic systems, has been proposed as a special form of recurrent neural network. However, most of the proposed ESNs consist of complex reservoir structures, leading to excessive computational cost. Recently, minimum complexity ESNs were proposed and proved to exhibit high performance and low computational cost. In this paper, we propose a simple deterministic ESN with a loop reservoir, i.e., an ESN with an adjacentfeedback loop reservoir. The novel reservoir is constructed by introducing regular adjacent feedback based on the simplest loop reservoir. Only a single free parameter is tuned, which considerably simplifies the ESN construction. The combination of a simplified reservoir and fewer free parameters provides superior prediction performance. In the benchmark datasets and real-world tasks, our scheme obtains higher prediction accuracy with relatively low complexity, compared to the classic ESN and the minimum complexity ESN. Furthermore, we prove that all the linear ESNs with the simplest loop reservoir possess the same memory capacity, arbitrarily converging to the optimal value. © Zhejiang University and Springer-Verlag Berlin Heidelberg 2012.

Thi, TH, Cheng, L, Zhang, J, Wang, L & Satoh, S 2012, 'Integrating local action elements for action analysis', Computer Vision and Image Understanding, vol. 116, no. 3, pp. 378-395.
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In this paper, we propose a framework for human action analysis from video footage. A video action sequence in our perspective is a dynamic structure of sparse local spatial-temporal patches termed action elements, so the problems of action analysis in video are carried out here based on the set of local characteristics as well as global shape of a prescribed action. We first detect a set of action elements that are the most compact entities of an action, then we extend the idea of Implicit Shape Model to space time, in order to properly integrate the spatial and temporal properties of these action elements. In particular, we consider two different recipes to construct action elements: one is to use a Sparse Bayesian Feature Classifier to choose action elements from all detected Spatial Temporal Interest Points, and is termed discriminative action elements. The other one detects affine invariant local features from the holistic Motion History Images, and picks up action elements according to their compactness scores, and is called generative action elements. Action elements detected from either way are then used to construct a voting space based on their local feature representations as well as their global configuration constraints. Our approach is evaluated in the two main contexts of current human action analysis challenges, action retrieval and action classification. Comprehensive experimental results show that our proposed framework marginally outperforms all existing state-of-the-arts techniques on a range of different datasets. © 2011 Elsevier Inc. All rights reserved.

Thi, TH, Cheng, L, Zhang, J, Wang, L & Satoh, S 2012, 'Structured learning of local features for human action classification and localization', Image and Vision Computing, vol. 30, no. 1, pp. 1-14.
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Human action recognition is a promising yet non-trivial computer vision field with many potential applications. Current advances in bag-of-feature approaches have brought significant insights into recognizing human actions within complex context. It is, however, a common practice in literature to consider action as merely an orderless set of local salient features. This representation has been shown to be oversimplified, which inherently limits traditional approaches from robust deployment in real-life scenarios. In this work, we propose and show that, by taking into account global configuration of local features, we can greatly improve recognition performance. We first introduce a novel feature selection process called Sparse Hierarchical Bayes Filter to select only the most contributive features of each action type based on neighboring structure constraints. We then present the application of structured learning in human action analysis. That is, by representing human action as a complex set of local features, we can incorporate different spatial and temporal feature constraints into the learning tasks of human action classification and localization. In particular, we tackle the problem of action localization in video using structured learning with two alternatives: one is Dynamic Conditional Random Field from probabilistic perspective; the other is Structural Support Vector Machine from max-margin point of view. We evaluate our modular classification-localization framework on various testbeds, in which our proposed framework is proven to be highly effective and robust compared against bag-of-feature methods. © 2011 Elsevier B.V. All rights reserved.

Wenzhi, W, Sheng, Y, Xianling, L, Ronghong, J, Bird, TS, Guo, YJ & Junping, G 2012, 'Even- and Odd-Mode Analysis of Thick and Wide Transverse Slot in Waveguides Based on a Variational Method', IEEE Transactions on Microwave Theory and Techniques, vol. 60, no. 11, pp. 3349-3358.
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Based on a new variational method, an even- and odd-mode analysis of transverse coupling slot between waveguides is presented. The proposed method is capable of dealing with slots of finite wall thickness. It uses multiple incident waves with symmetry to simplify the field distribution in the vicinity of the slot, enabling the adoption of one-expansion-term trial functions with sufficient accuracy, even in the instance of wide slots. Analytical solutions are provided, and the calculated results demonstrate excellent agreement with those of numerical simulation. The computation time with the new formulation is, however, significantly shorter. © 1963-2012 IEEE.

Xiao, X, Xu, C, Wang, J & Xu, M 2012, 'Enhanced 3-D Modeling for Landmark Image Classification', IEEE Transactions on Multimedia, vol. 14, no. 4, pp. 1246-1258.
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Landmark image classification is a challenging task due to the various circumstances, e.g., illumination, viewpoint, zoom in/out and occlusion under which landmark images are taken. Most existing approaches utilize features extracted from the whole image including both landmark and non-landmark areas. However, non-landmark areas introduce redundant and noisy information. In this paper, we propose a novel approach to improve landmark image classification consisting of three steps. First, an attention-based 3-D reconstruction method is proposed to reconstruct sparse 3-D landmark models. Second, the sparse 3-D models are projected onto iconic images in order to identify images of the hot regions. For a landmark, hot regions are parts of a landmark which attract photographers' attention and are popularly captured in photos. These hot region images are later used to enhance reconstructed sparse 3-D models. Third, the landmark regions are obtained through mapping the enhanced 3-D models to landmark images. A k-dimensional tree (kd-tree) is then constructed for each landmark based on scale invariant feature transform (SIFT) features extracted from the landmark area to classify unlabeled images into pre-defined landmark categories. The proposed method is evaluated using 291661 images of 51 landmarks. Experiments of comparison indicate that our method outperforms bag-of-words (BoW) based approach 18.5% and method of spatial-pyramid-matching using sparse-coding (ScSPM) 8.4%. © 2012 IEEE.

Xu, D, Yang, Y, Cheng, H, Li, YY & Zhang, K 2012, 'Integration of nano-Al with Co3O4 nanorods to realize high-exothermic core–shell nanoenergetic materials on a silicon substrate', Combustion and Flame, vol. 159, no. 6, pp. 2202-2209.
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Xu, J, Wu, Q, Zhang, J & Tang, Z 2012, 'Fast and Accurate Human Detection Using a Cascade of Boosted MS-LBP Features', IEEE Signal Processing Letters, vol. 19, no. 10, pp. 676-679.
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In this letter, a new scheme for generating local binary patterns (LBP) is presented. This Modified Symmetric LBP (MS-LBP) feature takes advantage of LBP and gradient features. It is then applied into a boosted cascade framework for human detection. By combining MS-LBP with Haar-like feature into the boosted framework, the performances of heterogeneous features based detectors are evaluated for the best trade-off between accuracy and speed. Two feature training schemes, namely Single AdaBoost Training Scheme (SATS) and Dual AdaBoost Training Scheme (DATS) are proposed and compared. On the top of AdaBoost, two multidimensional feature projection methods are described. A comprehensive experiment is presented. Apart from obtaining higher detection accuracy, the detection speed based on DATS is 17 times faster than HOG method. © 1994-2012 IEEE.

Xu, M, He, X, Peng, Y, Jin, JS, Luo, S, Chia, L-T & Hu, Y 2012, 'Content on demand video adaptation based on MPEG-21 digital item adaptation', EURASIP Journal on Wireless Communications and Networking, vol. 2012, no. 1, pp. 1-16.
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One of the major objectives in multimedia research is to provide pervasive access and personalized use of multimedia information. Pervasive access of video data implies the access of cognitive and affective aspects of video content. Personalized use requires the services satisfy individual user's needs on video content. This article attempts to provide a content-on-demand (CoD) video adaptation solution by considering users' preference on cognitive content and affective content for video media in general, sports video and movies in particular. In this article, CoD video adaptation system is developed to support users' decision in selecting their content of interest and adaptively deliver video source by selecting relevant content and dropping frames while considering network conditions. First, video contents are annotated by the description schemes (DSs) provided by MPEG-7 multimedia description schemes (MDSs). Then, to achieve a generic adaptation solution, the adaptation is developed following MPEG-21 Digital Item Adaptation (DIA) framework. We study the MPEG-21 reference software on XML generation and develop our own system for CoD video adaptation in three steps: (1) the content information is parsed from MPEG-7 annotation XML file together with bitstream to generate generic Bitstream Syntax Description (gBSD); (2) Users' preference, network characteristic and adaptation QoS (AQoS) are considered for making adaptation decision; (3) adaptation engine automatically parses adaptation decisions and gBSD to achieve adaptation. Unlike most existing adaptation work, the system adapts the content of interest in the video stream according to users' preference. We implement the above-mentioned MPEG-7 and MPEG-21 standards and provide a generic video adaptation solution. Adaptation based on gBSD avoids complex video computation. Thirty students from various departments were invited to assess the system and their responses have been positive. © 2012 Xu et al.

Yang, X, Tao, X, Cui, Q & Jay Guo, Y 2012, 'Interference-constrained adaptive simultaneous spectrum sensing and data transmission scheme for unslotted cognitive radio network', EURASIP Journal on Wireless Communications and Networking, vol. 2012, no. 1, pp. 1-12.
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Cognitive radio (CR) is widely recognized as a novel approach to improve the spectrum efficiency. However, there exists one problem needed to be resolved urgently, that is the two conflicting goals in CR network: one is to minimize the interference to primary (licensed) system; the other is to maximize the throughput of secondary (unlicensed) system. Meanwhile, the secondary user (SU) has to monitor the spectrum continuously to avoid the interference to primary user (PU), thus the throughput of the secondary system is affected by how often and how long the spectrum sensing is performed. Aiming to balance the two conflicting goals, this article proposes a novel Interference-Constrained Adaptive Simultaneous spectrum Sensing and data Transmission (ICASST) scheme for unslotted CR network, where SUs are not synchronized with PUs. In the ICASST scheme, taking advantage of the statistic information of PU’s activities, the data transmission time is adaptively adjusted to avoid the interference peculiar to unslotted CR network; the operation of spectrum sensing is moved to SU receiver from SU transmitter to increase the data transmission time and hence improve the throughput of SU. Simulation results validate the efficiency of ICASST scheme, which significantly increases the throughput of secondary system and decreases the interference to PU simultaneously. © 2012 Yang et al.

Yang, X, Tao, X, Guo, YJ, Huang, X & Cui, Q 2012, 'Subsampled circulant matrix based analogue compressed sensing', Electronics Letters, vol. 48, no. 13, pp. 767-768.
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The modulated wideband converter (MWC) is an attractive analogue compressed sensing technique proposed recently. Unfortunately, the MWC has high hardware complexity owing to its parallel structure. To reduce the complexity, proposed is a novel subsampled circulant matrix based analogue compressed sensing (SCM-ACS) scheme. Using the cyclic shifts of the Zadoff-Chu sequence, the SCM-ACS scheme reduces the number of physical parallel channels from m to 1 with larger processing time, where m ranges from several dozen to several hundred. It is proved that when m=O(r log 2 M log 3 r) the measurement matrix of the SCM-ACS scheme satisfies the restricted isometry property condition with probability 1-M -O(1), where M is the length of the Zadoff-Chu sequence, and r is the sparsity of the input signal. Simulation results show that the SCM-ACS scheme outperforms the MWC on recovery performance. © 2012 The Institution of Engineering and Technology.

Yang, Y, Roy, SM, Karmakar, NC & Zhu, X 2012, 'A NOVEL NARROW BANDPASS FILTER FOR IMAGE REJECTION AND CHANNEL SELECTION IN A WIRELESS SLEEP APNOEA MONITORING SYSTEM', Progress In Electromagnetics Research, vol. 125, pp. 483-501.
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A highly compact bandpass filter (BPF) is designed with a capacitively-coupled compact ring resonator. The ground plane is perturbed with a combination of two inter-digital and two spiral defected ground structures (DGSs), which enhance the selectivity and suppress the higher order harmonics of the BPF respectively. The filter has a selectivity of 0.22 dB/MHz, passband insertion loss (IL) of 1.55 dB and bandwidth of 61MHz at 2.53 GHz. The proposed compact ring resonator yields a size reduction of 70.5% compared to a conventional ring resonator. This BPF is significant for wireless telemetry monitoring systems for physiological parameters including electrocardiogram (ECG), electroencephalography (EEG) and electromyography (EMG) using portable devices.

Yang, Y, Zhu, X & Karmakar, NC 2012, 'A novel microstrip lowpass filter using compact microstrip resonant cells and uniquely shaped defected ground structures', Microwave and Optical Technology Letters, vol. 54, no. 11, pp. 2462-2464.
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AbstractA novel microstrip lowpass filter (LPF) with high selectivity and wide stopband is proposed in this letter.The proposed LPF consists of three compact microstrip resonant cells, two E‐shaped feed‐lines on the top layer and four defected ground structure (DGS) slots on the ground plane. The top layer LPF is designed to have a sharp roll‐off characteristic, whereas the engineered DGS slots on the ground plane are used to reduce the passband ripples and extend the stopband bandwidth of the proposed LPF. A selectivity of 53.4 dB/GHz is achieved. The stopband with an attenuation level of 20 dB is obtained from 2.96 to 13.2 GHz. The filter is optimally designed, fabricated, and measured. Both simulated and measured results are presented, which show a good agreement between simulation and measurement. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:2462–2464, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27126

Yang, Y, Zhu, X & Karmakar, NC 2012, 'Compact microstrip lowpass filter for harmonics suppression using a new defected ground structure', Microwave and Optical Technology Letters, vol. 54, no. 6, pp. 1385-1387.
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AbstractA compact microstrip lowpass filter (LPF) for harmonics suppression is proposed. An open stub LPF with uniquely shaped defect ground structure cells is used to optimize the LPF performance. A stopband attenuation of greater than 20 dB is obtained from 3.42 GHz to more than 18 GHz. The physical size of the proposed LPF, excluding transmission lines, is only 10 × 15 mm2. Good agreements between simulation and measurements are observed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1385–1387, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26809

Yang, Y, Zhu, X & Karmakar, NC 2012, 'Microstrip lowpass filter based on split ring and complementary split ring resonators', Microwave and Optical Technology Letters, vol. 54, no. 7, pp. 1723-1726.
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AbstractA novel split ring and complementary split ring resonator is proposed in this letter.The proposed resonator can generate two notches without increasing the physical size. A microstrip lowpass filter (LPF) is designed based on the proposed resonator. The cutoff frequency of the designed LPF is 3.7 GHz and the stopband with an attenuation level lower than −20 dB is obtained from 3.9 to 7.5 GHz. The selectivity is calculated to be 85 dB/GHz. The physical size of the LPF with transmission lines is 29 × 6 mm2. A good agreement between simulated and measured results is achieved. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1723–1726, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26887

Yu, K & Dutkiewicz, E 2012, 'Correction to “Geometry and Motion-Based Positioning Algorithms for Mobile Tracking in NLOS Environments”', IEEE Transactions on Mobile Computing, vol. 11, no. 4, pp. 704-704.
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Yue, XD, Miao, DQ, Zhang, N, Cao, LB & Wu, Q 2012, 'Multiscale roughness measure for color image segmentation', Information Sciences, vol. 216, pp. 93-112.
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Color image segmentation is always an important technique in image processing system. Highly precise segmentation with low computation complexity can be achieved through roughness measurement which approximate the color histogram based on rough set theory. However, due to the imprecise description of neighborhood similarity, the existing roughness measure tends to over-focus on the trivial homogeneous regions but is not accurate enough to measure the color homogeneity. This paper aims to construct a multiscale roughness measure through simulating the human vision. We apply the theories of linear scale-space and rough sets to generate the hierarchical roughness of color distribution under multiple scales. This multiscale roughness can tolerate the disturbance of trivial regions and also can provide the multilevel homogeneity representation in vision, which therefore produces precise and intuitive segmentation results. Furthermore, we propose roughness entropy for scale selection. The optimal scale for segmentation is decided by the entropy variation. The proposed method shows the encouraging performance in the experiments based on Berkeley segmentation database. © 2012 Elsevier Inc. All rights reserved.

Zhang, J 2012, 'Generalized plaid models', Neurocomputing, vol. 79, pp. 95-104.
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Zhang, J, Li, N, Yang, Q & Hu, C 2012, 'Self-adaptive chaotic differential evolution algorithm for solving constrained circular packing problem', Journal of Computational Information Systems, vol. 8, no. 18, pp. 7747-7755.
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Circles packing into a circular container with equilibrium constraint is a NP hard layout optimization problem. It has a broad application in engineering. This paper studies a two-dimensional constrained packing problem. Classical differential evolution for solving this problem is easy to fall into local optima. An adaptive chaotic differential evolution algorithm is proposed to improve the performance in this paper. The weighting parameters are dynamically adjusted by chaotic mutation in the searching procedure. The penalty factors of the fitness function are modified during iteration. To keep the diversity of the population, we limit the population's concentration. To enhance the local search capability, we adopt adaptive mutation of the global optimal individual. The improved algorithm can maintain the basic algorithm's structure as well as extend the searching scales, and can hold the diversity of population as well as increase the searching accuracy. Furthermore, our improved algorithm can escape from premature and speed up the convergence. Numerical examples indicate the effectiveness and efficiency of the proposed algorithm. © 2012 Binary Information Press.

Zhang, JA & Huang, X 2012, 'Autocorrelation Based Coarse Timing with Differential Normalization', IEEE Transactions on Wireless Communications, vol. 11, no. 2, pp. 526-530.
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Two novel differential normalization factors, depending on the severity of carrier frequency offset, are proposed for autocorrelation based coarse timing scheme. Compared with the conventional normalization factor based on signal energy, they improve the robustness of the timing metric to signal-to-noise ratio (SNR), improve the mainlobe sharpness of the timing metric and reduce both missed detection and false alarm probabilities. © 2012 IEEE.

Zhang, JA, Huang, X & Suzuki, H 2012, 'Phase-Shifted Interpolation for Complex Signals', IEEE Communications Letters, vol. 16, no. 9, pp. 1466-1469.
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This letter proposes simple algorithms for computing a phase shift term, which is introduced to greatly improve the accuracy of complex signal interpolation, applicable to any interpolator. Based on a cost function targeting at minimizing the phase transition between adjacent samples, the phase shift term can be easily computed using either signal statistics obtained in advance or known base samples in real time. Simulation results, exemplified for channel interpolation in OFDM systems, show that the proposed phase estimators can significantly improve the interpolation performance for various interpolators such as spline, low-pass filter, and linear and cubic polynomial interpolators, compared to the case without phase shifting. © 2012 IEEE.

Zhang, JA, Huang, X, Cantoni, A & Guo, YJ 2012, 'Sidelobe Suppression with Orthogonal Projection for Multicarrier Systems', IEEE Transactions on Communications, vol. 60, no. 2, pp. 589-599.
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Sidelobe suppression, or out-of-band emission reduction, in multicarrier systems is conventionally achieved via time-domain windowing which is spectrum inefficient. Although some sidelobe cancellation and signal predistortion techniques have been proposed for spectrum shaping, they are generally not well balanced between complexity and suppression performance. In this paper, an efficient and low-complexity sidelobe suppression with orthogonal projection (SSOP) scheme is proposed. The SSOP scheme uses an orthogonal projection matrix for sidelobe suppression, and adopts as few as one reserved subcarrier for recovering the distorted signal in the receiver. Unlike most known approaches, the SSOP scheme requires multiplications as few as the number of subcarriers in the band, and enables straightforward selection of parameters. Analytical and simulation results show that more than 50dB sidelobe suppression can be readily achieved with only a slight degradation in receiver performance. © 2012 IEEE.

Zhang, T, Du, J, Guo, YJ & Sun, X 2012, 'Design and integration of HTS filters with a Josephson device', Superconductor Science and Technology, vol. 25, no. 10, pp. 105014-105014.
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A high-temperature superconducting (HTS) Josephson frequency down-converting module is demonstrated. An HTS monolithic frequency down-converting circuit and a biasing circuit board for the Josephson device are packaged into the module. The monolithic circuit consists of HTS filters and a Josephson oscillator-mixer device, integrated on a single 10mm×20mm chip of Y Ba 2 Cu 3 O 7x (YBCO) film on MgO substrate. A compact, low-loss HTS step-impedance low-pass filter was designed for the intermediate frequency (IF) output port. The modeling, simulation and measurement results of the HTS low-pass filter are presented in this paper. The frequency response and dynamic range of the on-chip integrated HTS down-converting module are also described. © 2012 IOP Publishing Ltd.

Zhang, T, Du, J, Guo, YJ & Sun, X-W 2012, 'On-chip integration of HTS bandpass and lowpass filters with Josephson mixer', Electronics Letters, vol. 48, no. 12, pp. 729-731.
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A compact high-T c superconducting (HTS) monolithic downconverter is presented. The HTS passive and active devices are integrated on one single chip to achieve compactness and high coupling efficiency. The downconverter consists of a HTS YBa 2 Cu 3 O 7-x (YBCO) bandpass filter for RF input, a lowpass filter for IF output, and a self-pumped step-edge Josephson heterodyne mixer fabricated on a 20 ×10mm MgO substrate. Characterisations of the HTS filters and the frequency response of the on-chip integrated downconverter are reported. The results demonstrate the potential of the HTS downconverter for applications in wireless communications. © 2012 The Institution of Engineering and Technology.

Zhou, A, Liu, M, Li, Z & Dutkiewicz, E 2012, 'Cross-Layer Design for Proportional Delay Differentiation and Network Utility Maximization in Multi-Hop Wireless Networks', IEEE Transactions on Wireless Communications, vol. 11, no. 4, pp. 1446-1455.
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Zhou, A, Liu, M, Li, Z & Dutkiewicz, E 2012, 'Modeling and Optimization of Medium Access in CSMA Wireless Networks with Topology Asymmetry', IEEE Transactions on Mobile Computing, vol. 11, no. 9, pp. 1559-1571.
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Zhu, H, Chu, Q-X & Tian, X-K 2012, 'Compact UWB bandpass filter using folded-T-shaped resonator with a notch-band', Journal of Electromagnetic Waves and Applications, vol. 26, no. 10, pp. 1366-1373.
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AL Sabbagh, A, Braun, R & Abolhasan, M 1970, 'A power efficient RAT selection algorithm for heterogeneous wireless networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, Australia, pp. 997-1002.
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The Fourth Generation of wireless network (4G) is a heterogeneous network where different Radio Access Technologies (RATs) are integrated. This requires a need for Common Radio Resource Management (CRRM) to support efficient utilization of radio resources and to provide the required Quality of Service (QoS) for allocated calls. RAT selection algorithms are an important part of CRRM. This paper proposes an intelligent hybrid power efficient RAT selection algorithm (patent pending1). It is a battery power saver algorithm which includes sorting available RATs, collecting information on each RAT using the IEEE P1900.4 Protocol, and making decisions for selecting the most suitable RAT for incoming calls. The proposed power efficient algorithm is compared to centralized and distributed algorithms in terms of new call blocking and Vertical Handover (VHO) call dropping probabilities. Users' satisfactions probability and saving battery power percentage are also compared. Simulation results show that the proposed algorithm performs better than the centralized and distributed algorithms in terms of blocking, dropping and users' satisfactions probabilities. The proposed and the distributed algorithms have similar performance in term of saving battery power, and both perform better than the centralized algorithm. © 2012 IEEE.

Al Sabbagh, A, Braun, RM & Abolhasan, M 1970, 'Interaction of Radio Resource Management in Heterogeneous wireless Networks', 1st Australian Conference on the Applications of Systems Engineering (ACASE'12), 1st Australian Conference on the Applications of Systems Engineering (ACASE'12), University of Technology, Sydney, Sydney, Australia, pp. 34-35.

AlAamri, H, Safaei, F, Abolhasan, M & Franklin, DR 1970, 'Location-Based Utilization for Unidirectional Links in MANETs', Proceedings of the Eighth International Conference on Wireless and Mobile Communications, International Conference on Wireless and Mobile Communications, XPS (Xpert Publishing Services) / IARIA, Venice, Italy, pp. 248-253.
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AbstractHeterogeneous Mobile Ad hoc Network(HMANET) comprises different nodes with different capabilities. Hence, transmission and receiving capabilities aredifferent. This causes unidirectionality problem. Avoidances is the most used strategy in researches to route data, e.g., Blacklist. In this paper, we proposed a strategy for on-demand routing protocols to detect unidirectional link and resolve it in timely fashion. This strategy is based on utilizing locations of nodes to filter and cache incoming RREQ packets to find reliable path to destination in the existence of unidirectional links. Simulation results show that our strategy outperforms Blacklist strategy in homogeneous and heterogeneous MANET.

Arya, V & Veitch, D 1970, 'Sparsity without the Complexity: Loss Localisation Using Tree Measurements', NETWORKING 2012 Proceedings, Part I (LNCS), International IFIP-TC Networking Conference, Springer Berlin Heidelberg, Prague, Czech Republic, pp. 289-303.
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We study network loss tomography based on observing average loss rates over a set of paths forming a tree – a severely underdetermined linear problem for the unknown link loss probabilities. We examine in detail the role of sparsity as a regularising principle, pointing out that the problem is technically distinct from others in the compressed sensing literature. While sparsity has been applied in the context of tomography, key questions regarding uniqueness and recovery remain unanswered. Our work exploits the tree structure of path measurements to derive sufficient conditions for sparse solutions to be unique and the condition that ℓ1 minimization recovers the true underlying solution. We present a fast single-pass linear algorithm for ℓ1 minimization and prove that a minimum ℓ1 solution is both unique and sparsest for tree topologies. By considering the placement of lossy links within trees, we show that sparse solutions remain unique more often than is commonly supposed. We prove similar results for a noisy version of the problem.

Bargi, A, Da Xu, RY & Piccardi, M 1970, 'An online HDP-HMM for joint action segmentation and classification in motion capture data', 2012 IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops, 2012 IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops (CVPR Workshops), IEEE, Providence RI, USA, pp. 1-7.
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Since its inception, action recognition research has mainly focused on recognizing actions from closed, predefined sets of classes. Conversely, the problem of recognizing actions from open, possibly incremental sets of classes is still largely unexplored. In this paper, we propose a novel online method based on the âsticky❠hierarchical Dirichlet process and the hidden Markov model [11, 5]. This approach, labelled as the online HDP-HMM, provides joint segmentation and classification of actions while a) processing the data in an online, recursive manner, b) discovering new classes as they occur, and c) adjusting its parameters over the streaming data. In a set of experiments, we have applied the online HDP-HMM to recognize actions from motion capture data from the TUM kitchen dataset, a challenging dataset of manipulation actions in a kitchen [12]. The results show significant accuracy in action classification, time segmentation and determination of the number of action classes

Bin Ahmad, MR, Mohd Esa, MR, Cooray, V & Dutkiewicz, E 1970, 'Performance analysis of audio streaming over lightning-interfered MIMO channels', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 513-518.
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This paper evaluates the interference from lightning flashes on the quality of audio streaming transmission over MIMO wireless system operating at 2.4 GHz. A consecutive lost datagram (CLD) measurement method was used to evaluate the transmission quality during 3 heavy thunderstorms on January 25, March 17, and March 20, 2011. In addition, CLD measurements also were done on January 21 and March 30, 2011 under fair weather (FW) conditions providing a baseline for comparison. We infer that lightning interfered with the transmitted digital pulses which resulted in a higher recorded number of lost packets per burst. We found the audio streaming quality is degraded significantly during all thunderstorms. © 2012 IEEE.

Braun, R & Chaczko, Z 1970, 'Multi-dimensional Information Space View of Wireless Sensor Networks with Optimization Applications', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), International Conference on Computer Aided Systems Theory (EUROCAST), Springer Berlin Heidelberg, Las Palmas de Gran Canaria, Spain, pp. 146-152.
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This paper presents an optimization example using a new paradigm for viewing the work of Wireless Sensor Networks. In our earlier paper [1] the Observed Field (OF) is described as a multi-dimensional 'Information Space' (ISp). The Wireless Sensor Network is described as a 'Transformation Space' (TS), while the information collector is a single point consumer of information, described as an 'Information Sink' (ISi). Formal mathematical descriptions were suggested for the OF and the ISp. We showed how the TS can be formally thought of as a multi-dimensional transform function between ISp and ISi. It can be aggregated into a notional multi-dimensional value between {0,1}. In this paper, this formal mathematical description is used to create a genetic algorithm based optimization strategy for creating routes through the TS, using a cost function based on mutual information. The example uses a connectivity array, a mutual information array and the PBIL algorithm. © 2012 Springer-Verlag.

Braun, R, Chaczko, Z, Neilson, M & Aslanzadeh, S 1970, 'A practical approach for redesigning system engineering processes', 2012 International Conference on Information Technology Based Higher Education and Training (ITHET), 2012 11th International Conference on Information Technology Based Higher Education and Training (ITHET), IEEE, Istanbul, pp. 1-8.
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This paper describes the methodology of applying Business Process Reengineering and Total Quality Management principles to a model a telecommunications service and infrastructure provider company. By applying these principles to existing processes this paper aims to provide redefined and reengineered processes for consideration of implementation into the company's business model. The processes that this paper is focusing on are purely engineering based processes and as such, do not represent, change or consider processes outside of the engineering department. The overall aim of this paper is to demonstrate a typical use of methodology and ICT tools that can be used for training students in the improvement of engineering processes and to enable them to design a more streamlined and productive work environment. © 2012 IEEE.

Chaczko, Z & Szymanski, J 1970, 'Teaching multidisciplinary engineering using concepts and technology of WSN', 2012 International Conference on Information Technology Based Higher Education and Training (ITHET), 2012 11th International Conference on Information Technology Based Higher Education and Training (ITHET), IEEE, Bogazici University, Istanbul, Turkey, pp. 1-7.
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Topic(s) : Communication, Networking & Broadcasting ; Computing & Processing (Hardware/Software) ; General Topics for Engineers (Math, Science & Engineering) Conference Location : Istanbul Print ISBN: 978-1-4673-2332-1 INSPEC Accession Number: 12882984 Digital Object Identifier : 10.1109/ITHET.2012.6246055 Date of Current Version : 23 July 2012 Issue Date : 21-23 June 2012

Chaczko, Z, Klempous, R, Nikodem, J & Aslanzadeh, S 1970, 'Group-work teaching and learning involving 3 Time Zones (3TZ) model of collaboration in the global workspace', 2012 International Conference on Information Technology Based Higher Education and Training (ITHET), 2012 11th International Conference on Information Technology Based Higher Education and Training (ITHET), IEEE, Istanbul, Turkey, pp. 1-7.
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This paper discusses concepts of group-work teaching and learning of practice based subjects within ICT engineering programs using 3 Time Zones (3TZ) collaborative, global workspace environment. The methodology intends to explore and evaluate a new collaborative framework for teaching system analysis and design, as well as software engineering in higher education, using new convergent technologies. The project is compatible with a model of teaching and learning that involves a blend of three interrelated features: an integrated exposure to professional practice and multidisciplinary skills, a practice situated in a global environment, as well as a research inspired and integrated learning. © 2012 IEEE.

Chen, Y, Liu, RP, Wang, C, de Groot, M & Zeng, Z 1970, 'Consumer Operational Comfort Level based power demand management in the smart grid', 2012 3rd IEEE PES Innovative Smart Grid Technologies Europe (ISGT Europe), 2012 3rd IEEE PES Innovative Smart Grid Technologies Europe (ISGT Europe), IEEE, Berlin, Germany, pp. 1-6.
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In the smart grid, peak-load shifting allows smart homes to limit their peak hour demand to reduce electricity cost. By means of balancing the demand and supply, efficiency and stability are achieved in the power grid. While most existing Demand Response (DR) programs only use pricing signals to encourage consumers to alter their power consumption patterns, the impacts on consumers have been overlooked. In this paper, we propose a novel demand management scheme that takes into account of the consumer comfort level. We define the concept of Operational Comfort Level (OCL), and construct the OCL models for a range of smart appliances. These OCL models are integrated into our load management scheme. We develop a Min-Max Load Scheduling (MMLS) algorithm to minimize the peak-to-average ratio (PAR), while maximize the OCL of consumers. Simulation results confirm that our proposed MMLS algorithm is able to achieve both peak-load shifting and energy cost saving with minimal impact on consumers' comfort levels. © 2012 IEEE.

Cheng, P, Gui, L, Tao, M, Guo, YJ, Huang, X & Rui, Y 1970, 'Sparse channel estimation for OFDM transmission over two-way works', 2012 IEEE International Conference on Communications (ICC), ICC 2012 - 2012 IEEE International Conference on Communications, IEEE, Ottawa, ON, Canada, pp. 3948-3953.
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Compressed sensing (CS) has recently emerged as a powerful signal acquisition paradigm. CS enables the recovery of high-dimensional sparse signals from much fewer samples than usually required. Further, quite a few recent channel measurement experiments show that many wireless channels also tend to exhibit sparsity. In this case, CS theory can be applicable to sparse channel estimation and its effectiveness has been validated in point-to-point (P2P) communication. In this work, we study sparse channel estimation for two-way relay networks (TWRN). Unlike P2P systems, applying CS theory to sparse channel estimation in TWRN is much more challenging. One issue is that the equivalent channels (terminal-relay-terminal) may be no longer sparse due to the linear convolutional operation. On this basis, novel schemes are proposed to solve this problem and effectively improve the accuracy of TWRN channel estimation when using CS theory. Extensive numerical results are provided to corroborate the proposed studies. © 2012 IEEE.

Chiu, C & Chaczko, Z 1970, 'Multi-dimensional Representations of Laparoscopic Simulations for SANETs', Proceedings of the Eurocast 2011, Computer Aided Systems Theory Conference, International Conference on Computer Aided Systems Theory (EUROCAST), Springer Berlin Heidelberg, Las Palmas de Gran Canaria, Spain, pp. 225-232.
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13th International Conference on Computer Aided Systems Theory Las Palmas de Gran Canaria, Spain, February 2011

Chiu, C, Chaczko, Z & Kong, X 1970, 'Design of an Intelligent Health System Using Evolutionary Middleware for Sensor Actor Networks', 2012 International Conference on Information Science and Applications, 2012 International Conference on Information Science and Applications (ICISA), IEEE, Suwon, South Korea, pp. 1-6.
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Information infrastructure for healthcare is undergoing a transformational shift in the way it is perceived and used by health professionals. This is driven by the need to unify patient records seamlessly, and integrate emerging technologies in the Sensor-Actor Network (SANET) realm that incorporate patient sensory systems such as wireless sensor networks and body-area networks. By harnessing The Open Group Architecture Framework (TOGAF), it ensures integrity is considered throughout development processes by analyzing the problem space and scenarios, constraints, requirements, risks, enablers and inhibitors of the legacy application architectures. The proposed architecture with TOGAF components incorporating SANETs addresses the need to harmonize legacy operations in a consistent manner with industry best practice to ensure universal patient records are comprehensive and secure, thus protecting against identity theft and adhering to privacy regulation compliance.

Davis, M, Villain, B, Ridoux, J, Orgerie, A-C & Veitch, D 1970, 'An IEEE-1588 compatible RADclock', 2012 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication Proceedings, 2012 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication (ISPCS), IEEE, San Franciscio, pp. 1-6.
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Du, R, Wu, Q, He, X & Yang, J 1970, 'Multi-Instance Learning with an Extended Kernel Density Estimation for Object Categorization', 2012 IEEE International Conference on Multimedia and Expo Workshops, 2012 IEEE International Conference on Multimedia & Expo Workshops (ICMEW), IEEE, Melbourne, Australia, pp. 477-482.
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Multi-instance learning (MIL) is a variational supervised learning. Instead of getting a set of instances that are labeled, the learner receives a set of bags that are labeled. Each bag contains many instances. In this paper, we present a novel MIL algorithm that can efficiently learn classifiers in a large instance space. We achieve this by estimating instance distribution using a proposed extended kernel density estimation (eKDE) which is an alternative to previous diverse density estimation (DDE). A fast method is devised to approximately locate the multiple modes of eKDE. Comparing to DDE, eKDE is more efficient and robust to the labeling noise (the mislabeled training data). We compare our approach with other state-of-the-art MIL methods in object categorization on the popular Caltech-4 and SIVAL datasets, the results illustrate that our approach provides superior performance. © 2012 IEEE.

Du, R, Wu, Q, He, X & Yang, J 1970, 'Object Categorization Based on a Supervised Mean Shift Algorithm', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), European Conference on Computer Vision, Springer Berlin Heidelberg, Florence, Italy, pp. 611-614.
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In this work, we present a C++ implementation of object categorization with the bag-of-word (BoW) framework. Unlike typical BoW models which consider the whole area of an image as the region of interest (ROI) for visual codebook generation, our implementation only considers the regions of target objects as ROIs and the unrelated backgrounds will be excluded for generating codebook. This is achieved by a supervised mean shift algorithm. Our work is on the benchmark SIVAL dataset and utilizes a Maximum Margin Supervised Topic Model for classification. The final performance of our work is quite encouraging. © 2012 Springer-Verlag.

Gernez, E, Harada, CM, Bootsman, R, Chaczko, Z, Levine, G & Keen, P 1970, 'Protei open source sailing drones: A platform for education in ocean exploration and conservation', 2012 International Conference on Information Technology Based Higher Education and Training (ITHET), 2012 11th International Conference on Information Technology Based Higher Education and Training (ITHET), IEEE, pp. 1-7.
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The Open-H2O community is developing ocean technology with the aim of co-designing the technology; licensing under the Open Source Software and Hardware protocols; and gathering ocean data from its different technology users and developers. Protei is a fleet of autonomous, shape-shifting, sailing vessels for ocean exploration and conservation, created by the Open-H2O community. This paper presents the tools and learning environments used during the development of Protei, and the opportunities created in terms of education and engagement of the Public, Scientific and Industrial sectors. Three case studies are presented, concluding with the challenges and education perspectives lying in the growth of the Open-H2O community. © 2012 IEEE.

Gill, AQ & Bunker, D 1970, 'Crowd Sourcing Challenges Assessment Index for Disaster Management.', AMCIS, Americas Conference on Information Systems, Association for Information Systems, Seattle, USA, pp. 4428-4438.
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Emergency agencies (EA) rely on inter-agency approaches to information management during disasters. EA have shown a significant interest in the use of cloud-based social media such as Twitter and Facebook for crowd-sourcing and distribution of disaster information. While the intentions are clear, the question of what are its major challenges are not. EA have a need to recognise the challenges in the use of social media under their local circumstances. This paper analysed the recent literature, 2010 Haiti earthquake and 2010-11 Queensland flood cases and developed a crowd sourcing challenges assessment index construct specific to EA areas of interest. We argue that, this assessment index, as a part of our large conceptual framework of context aware cloud adaptation (CACA), can be useful for the facilitation of citizens, NGOs and government agencies in a strategy for use of social media for crowd sourcing, in preventing, preparing for, responding to and recovering from disasters. © (2012) by the AIS/ICIS Administrative Office All rights reserved.

Gill, AQ, Bunker, D & Seltsikas, P 1970, 'Evaluating a communication technology assessment tool (CTAT): A case of a cloud based communication tool', Proceedings Pacific Asia Conference on Information Systems Pacis 2012, Pacific Asia Conference on Information Systems, AIS, Ho Chi Min, Vietnam, pp. 1-13.
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A primary concern of distributed adaptive development environment (DADE) is that of human communication and knowledge sharing among geographically dispersed developers. Emerging cloudbased communication technologies claim to provide a support for communication and knowledge sharing among developers in a DADE. However, the challenge is how to enable developers to self assess and select appropriate cloud-based communication technologies for their DADE. Based on our recent empirical study, we have developed the construct of a practical communication technologies assessment tool (CTAT). We argue that, CTAT construct, as a part of our large conceptual framework of context aware cloud adaptation (CACA), can be useful to assist developers in the self assessment of appropriate cloud-based communication technologies for their DADE. This paper presents the evaluation of the CTAT by using it for the assessment of the Force.com cloud-based Chatter communication tool. The main objective of this evaluation is to determine to what extent CTAT construct is relevant, valuable and sufficient to achieve its purpose. The results of this evaluation indicate that CTAT seems useful when performing vendor independent assessment of communication technologies in order to make an informed decision about the selection of a communication tool for the DADE.

Guo, YJ 1970, 'Antenna and RF technologies for future wireless communications systems', 2012 IEEE Asia-Pacific Conference on Antennas and Propagation, 2012 IEEE Asia-Pacific Conference on Antennas and Propagation (APCAP), IEEE, Singapore, Singapore, pp. 74-75.
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Owing to spectrum scarcity, omnipresence of interference, size restrictions and cost limitations, the proliferation of wireless communications systems has posed several major challenges to antenna and RF designers. This calls for new antenna technologies and advanced RF receivers for future systems. In this paper, research activities in wireless communications at CSIRO will be presented. In particular, we will focus on two areas, namely, reconfigurable antennas and integrated receivers employing high temperature superconducting (HTS) devices. The former would ease the demand on antenna real estate and enhance system performance. The latter would increase the sensitivity of receivers, thus enabling low power operation, greater coverage and the employment of novel interference cancellation techniques. © 2012 IEEE.

Hasan, MA, Xu, M, He, X & Chen, L 1970, 'Shot Classification Using Domain Specific Features for Movie Management', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), International Conference on DASFAA, Springer Berlin Heidelberg, Busan, South Korea, pp. 314-318.
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Among many video types, movie content indexing and retrieval is a significantly challenging task because of the wide variety of shooting techniques and the broad range of genres. A movie consists of a series of video shots. Managing a movie at shot level provides a feasible way for movie understanding and summarization. Consequently, an effective shot classification is greatly desired for advanced movie management. In this demo, we explore novel domain specific features for effective shot classification. Experimental results show that the proposed method classifies movie shots from wide range of movie genres with improved accuracy compared to existing work. © 2012 Springer-Verlag.

He, Y, Su, Y, Dutkiewicz, E, Huang, X & Shi, J 1970, 'An efficient implementation of uplink baseband signal generator in LTE UE transmitters', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 444-448.
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An efficient hardware-optimized uplink baseband signal generation algorithm and its ASIC implementation in the LTE user equipment (UE) transmitter are presented in this paper. Optimization covers top level as well as module level. A paralleled Turbo encoder and a Cooley-Tukey based DFT are proposed. The optimized algorithm achieves significantly lower computational complexity compared with the original algorithm in the LTE specification and better performance compared to the existing results. The ASIC architecture is designed to reduce the logic complexity and implemented in 55nm CMOS, which achieves short time latency and low hardware cost in terms of the cell area. © 2012 IEEE.

Hoang, DT & Niyato, D 1970, 'Performance analysis of cognitive machine-to-machine communications', 2012 IEEE International Conference on Communication Systems (ICCS), 2012 IEEE International Conference on Communication Systems (ICCS), IEEE, Singapore, SINGAPORE, pp. 245-249.
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Hoang, DT, Niyato, D & Wang, P 1970, 'Optimal admission control policy for mobile cloud computing hotspot with cloudlet', 2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012 IEEE Wireless Communications and Networking Conference (WCNC), IEEE, Paris, FRANCE, pp. 3145-3149.
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Hongyan Cui, Chen Feng, Ren Ping Liu, Xu Huang & Yunjie Liu 1970, 'Prolonging network lifetime in two-level heterogeneous Wireless Sensor Networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 871-876.
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It is important to prolong the network lifetime in Wireless Sensor Networks. There are two approaches to increase the network lifetime, which are balancing energy consumption and reducing the number of non-working nodes. This paper presents two Cluster head Selection algorithms, one is based on Ensuring target Area and the other is based on Affinity Propagation. We propose a method which makes the energy uniformly distributed throughout the network nodes. In particular, we analyse the effect of the powerful nodes on the network lifetime and cluster characteristics. Simulation results show that the two proposed algorithms distribute non-working nodes evenly, such that the target area is well covered by the remaining nodes. Our proposed algorithms balance the traffic load and energy distributions, and prolong the network lifetime effectively compared with the existing schemes. © 2012 IEEE.

Huang, Y & Huang, X 1970, 'Optimal spectrum sensing over multipath channels', 2012 IEEE International Conference on Communications (ICC), ICC 2012 - 2012 IEEE International Conference on Communications, IEEE, Ottawa, ON, Canada, pp. 1522-1527.
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Wireless propagation phenomena including multipath pose significant challenges to reliable spectrum sensing which is a fundamental requirement for dynamic spectrum access and system coexistence. In this paper, an optimal detection technique along with two reduced-complexity alternatives, modified energy detection (MED) and equal gain detection (EGD), are proposed to improve the detection probability for spectrum sensing over severe multipath channels. By incorporating the resolvable multipaths and multiple receiving antennas into the system model and assuming the availability of a priori temporal correlation about the source signal, these detection methods are derived based on maximum log-likelihood ratio test under low signal-to-noise ratio condition. Simulation results show that the proposed optimal detection outperforms the conventional generalized likelihood ratio test in a multipath environment either with or without a priori information. The proposed MED significantly improves the performance of conventional energy detection after a priori information is exploited. Finally, the proposed EGD performs better than MED and approaches the optimal detection as the number of multipaths increases. © 2012 IEEE.

Huang, Y & Huang, X 1970, 'Spectrum sensing over frequency-selective fading channel with tap and spatial correlations', 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC), 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC 2012), IEEE, Sydney., NSW, Australia, pp. 2143-2148.
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Reliable spectrum sensing should be able to operate under realistic wireless environments such as multipath and fading. Based on the optimal spectrum sensing with multiple receiver antennas over multipath channels, this paper presents further studies into two more practical detection methods, the modified energy detection (MED) and the equal gain detection (EGD), over frequency-selective fading channels, with focus on the impact of multipath tap correlation on the sensing performance. Both simulation and analytical results are provided. It is verified that utilizing multipath propagation enhances the detection probability of the EGD, which approaches that of the optimal detection. The EGD also demonstrates better performance than the MED and the conventional generalized likelihood ratio test. The tap correlation can have either constructive or destructive effect to the spectrum sensing system depending on how well the tap correlation matches the source signal's temporal correlation, whereas the spatial correlation always degrades the detection performance. © 2012 IEEE.

Huq, MA, Dutkiewicz, E, Gengfa Fang, Ren Ping Liu & Vesilo, R 1970, 'MEB MAC: Improved channel access scheme for medical emergency traffic in WBAN', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 371-376.
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Emergency data delivery is an important service for medical Wireless Body Area Networks. The successful dissemination of emergency messages can make a huge difference between life and death. The utmost importance of emergency message dissemination requires high reliability while the intermittent nature of alarms requires minimum channel access delay for almost instantaneous delivery. IEEE 802.15.6 beacon enabled networks have defined an adjustable superframe structure that consists of contention-free and contention access periods. Short superframes can satisfy the channel access delay requirements of emergency traffic but penalizes the energy efficiency of all devices in the network. On the other hand, long superframes increase the energy efficiency but the channel access delay is also increased. To balance this contradicting requirement of energy efficiency and Quality of Service, we propose the Medical Emergency Body (MEB) MAC protocol that inserts listening windows dynamically within the contention free periods. The frequency of listening window insertion is determined by the minimum delay tolerance. Furthermore, MEB MAC utilizes idle time slots to insert additional listening window opportunities for emergency traffic, without affecting the network throughput. Our analysis shows that MEB MAC is able to reduce channel access delay for emergency traffic especially for long superframe durations. Simulation results show the effectiveness of the MEB MAC scheme in serving emergency messages in medical body area networks. © 2012 IEEE.

Iji Ayobami, B, Zhu, F & Heimlich, M 1970, 'A down converter active mixer, in 0.25&#x00B5;m CMOS process for ultra wide-band applications', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD Australia, pp. 28-31.
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This paper presents improvement technique on linearity of a CMOS double balance Gilbert cell mixer with considerable high conversion gain at low power consumption. The mixer consists of inductive source degeneration in the transconductance stage providing impedance matching to improve linearity of the mixer. The mixer was designed to operate a Radio Frequency (RF) signal of 4GHz, a Local Oscillator frequency (LO) of 3.75GHz, thus providing an Intermediate Frequency (IF) of 0.25GHz. The circuit presents an Input third order Intercept point (IIP3) of +1dBm. A conversion gain of 10.45dB and a single sideband noise of 8dB over the band width. The DC power consumed by the core mixer is 4.5mW. The proposed active mixer design was made in 0.25μm CMOS Silanna process, suitable for wideband applications. © 2012 IEEE.

Iji Ayobami, B, Zhu, F, Heimlich, M & Dutkiewicz, E 1970, 'Proposed Ultra Wide-Band system, &amp; receiver circuit for implant wireless body area networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 139-142.
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Implant-able wireless body area networks (WBAN) are a promising technology for health monitoring and treatment for patients requiring special care and monitoring, where sensors are placed inside the human body to carry out measurements which may include telemetry or video streaming. Ultra Wide- Band technology (UWB) is investigated as a candidate for the proposed implanted wireless body area sensor network due to its wide frequency spectrum and, hence, its low bit energy. UWB is introduced and then explored in terms of system constraints and circuit implementation. The main focus of the paper is to describe how applicable UWB is used for implant WBANs and to invite future work on designing a radio capable of being installed inside the human body for medical care and monitoring. We have presented the RF front end receiver in 0.25μm CMOS Silanna process. © 2012 IEEE.

Iji, A, Zhu, X & Heimlich, M 1970, 'A 3&#x2013;5 GHz LNA in 0.25&#x00B5;m SOI CMOS process for implantable WBANs', 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), IEEE, Boise, ID, USA, pp. 766-769.
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A low-voltage, low-power single-ended LNA is implemented in a 0.25μm SOI CMOS technology. A theoretical basis for the design is used to develop design constraints in conjunction with a layout-aware design flow providing early insight into parasitic effects. The SOI CMOS LNA has a post-layout simulated noise figure of less than 3 dB; input IP3 of -10 dBm and small-signal gain of 19.2 dB within the 3-5 GHz band. Total current consumption is 5.2 mA from 1.5 V supply voltage. The LNA can also operate under a 1V supply voltage with relatively small linear performance degradation. The chip area is 0.89 mm 2 . Due to the high-resistivity silicon substrate, buried oxide isolation and low threshold voltage, the SOI CMOS technology offers significant performance improvements for LNAs, which makes the designed LNA well suitable for implantable WBANs. © 2012 IEEE.

Iji, A, Zhu, X & Heimlich, M 1970, 'A folded-switching mixer in SOI CMOS technology', 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), IEEE, Boise, ID, USA, pp. 458-461.
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A wideband 3.5 to 5.5GHz low voltage folded-switching mixer is implemented in 0.25um SOI CMOS technology. The post-layout simulation of the designed mixer at 4.5GHz has noise figure (NF) of 9.6dB, input IP3 of -9dBm, conversion gain (CG) of 10.9dB and total current consumption including bias is 4.5mA under 1.5V supply voltage. The designed mixer can also operate under 1V supply voltage with relatively small linear performances degradation. The chip area is 0.55×0.5mm 2 . Due to high-resistivity silicon substrate, buried oxide isolation and low threshold voltage, SOI CMOS technology offers significant performance improvements for mixers, which makes the designed mixer well suitable for low voltage and low power applications. © 2012 IEEE.

Iji, A, Zhu, X, Heimlich, M & Sun, Y 1970, 'An OTA-C filter in SOI CMOS for UWB application', 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), 2012 IEEE 55th International Midwest Symposium on Circuits and Systems (MWSCAS), IEEE, Boise, ID, USA, pp. 93-96.
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A 4 th -order Butterworth OTA-C lowpass filter based on voltage mode multiple loop feedback (MLF) inverse follow the leader feedback (IFLF) structure is implemented to support both MB-OFDM UWB and low data rate IR-UWB applications. The filter is implemented using a fully-differential linear operational transconductance amplifier (OTA) in 0.25μm SOI CMOS process. A positive feedback topology is used to form a negative resistance load; in such a way, the DC gain of OTA is enhanced. Moreover, the linearity is improved by means of active biasing. AWR simulations in a 0.25μm SOI CMOS process with 2.5V power supply have shown that the cut-off frequency of the filter ranges from 120MHz to 280MHz and dynamic range is about 54dB. The total power consumption is only 32mW at 250MHz cut-off frequency. © 2012 IEEE.

Iji, AB, Zhu, F & Heimlich, M 1970, 'Design of low power, wider tuning range CMOS voltage control oscillator for ultra wideband applications', 2012 IEEE International Conference on IC Design & Technology, 2012 IEEE International Conference on IC Design & Technology (ICICDT), IEEE, Austin, TX, USA, pp. 1-4.
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This paper presents a diode varactor and MOS varactor voltage control oscillators using 0.25μm CMOS technology, proposed for Ultra Wideband application. The VCOs are designed for 3-5GHz UWB Impulse Radio, The VCO's has 107.6 dBc/Hz and 108.8 dBc/Hz phase noise at 1 MHz offset frequency. The diode varactor VCO has a tuning range of 300 MHz and the MOS varactor VCO has a wider tuning range of 610 MHz which is very difficult to achieve. Their power consumption at the maximum oscillation frequency is 2.26 mW from a 1.2 V voltage source, with 9 dBm output power which is very low compared to the conventional VCO in similar process design. © 2012 IEEE.

Jayawickrama, BA, Dutkiewicz, E & Fang, G 1970, 'Spectrum sensing error optimisation in cognitive radio networks.', ISCIT, International Symposium on Communications and Information Technologies, IEEE, Gold Coast, Australia, pp. 787-792.
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Jian Zhang, Smith, D & Zhuo Chen 1970, 'Linear finite state Markov chain predictor for channel prediction', 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC), 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC 2012), IEEE, Sydney, NSW, Australia, pp. 2085-2089.
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Channel prediction, which predicts a future channel gain based on current and past observations, is very useful for power control and resource optimization in wireless communication systems. However, a low-complexity predictor with trustworthy prediction accuracy is yet to be developed. This paper proposes a linear predictor and two linear Markov predictors, which achieve a good balance between complexity and accuracy. © 2012 IEEE.

Jian Zhang, Xiaojing Huang, Suzuki, H & Zhuo Chen 1970, 'Phase-shifted interpolation for channel matrix inversion in MIMO-OFDM systems', 2012 IEEE International Conference on Communications (ICC), IEEE International Conference on Communications (ICC 2012), IEEE, Ottawa, ON, Canada, pp. 3831-3835.
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Channel matrix inversion, which requires significant hardware resource and computational power, is a very challenging problem in MIMO-OFDM systems. Casting the frequency-domain channel matrix into a polynomial matrix, interpolation-based matrix inversion provides a promising solution to this problem. In this paper, by showing that the polynomial coefficients can be well approximated by a Gaussian function, we propose an efficient algorithm, which relaxes the requirement for knowing the maximum multipath delay spread and enables the use of simple low-complexity interpolators by introducing a phase shift term to the signal to be interpolated. Simulation results show that significant complexity saving can be achieved with little equalization performance degradation. © 2012 IEEE.

Jin Lai, Dutkiewicz, E, Ren Ping Liu & Vesilo, R 1970, 'Comparison of cooperative spectrum sensing strategies in distributed cognitive radio networks', 2012 IEEE Global Communications Conference (GLOBECOM), GLOBECOM 2012 - 2012 IEEE Global Communications Conference, IEEE, Anaheim, CA, USA, pp. 1513-1518.
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Cooperative spectrum sensing has been proposed to significantly improve spectrum sensing accuracy by taking advantage of the cooperation among secondary users (SUs), but also this incurs some sensing cost. In this paper, we present a cooperative spectrum sensing model with consideration to spectrum sensing cost in distributed cognitive radio networks where each SU aims to maximize its utility. Under the scenario with selfish SUs, we formulate cooperative spectrum sensing as a non-cooperative game and obtain the mixed strategy Nash equilibrium of the formulated spectrum sensing game by deriving the sensing probabilities of SUs. Under the scenario with limited collaboration of SUs, we formulate cooperative spectrum sensing as a nonlinear optimization problem and derive the optimal sensing strategy of SUs by using our proposed Newton-Raphson based algorithm. Numerical results demonstrate that SUs with limited collaboration are able to achieve much better performance than the outcome of the Nash equilibrium and by choosing the optimal sensing strategy SUs are able to maximize their utility, which is an effective tradeoff between SU throughput and sensing cost. © 2012 IEEE.

Kazemi, R, Vesilo, R, Dutkiewicz, E & Liu, RP 1970, 'Design considerations of reinforcement learning power controllers in Wireless Body Area Networks', 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC), 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC 2012), IEEE, Sydney, NSW, Australia, pp. 2030-2036.
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A Wireless Body Area Network (WBAN) comprises a number of tiny devices implanted in/on the body that sample physiological signals of the human body and send them to a coordinator node for medical or other purposes. As these miniature devices run on built-in batteries, energy is the most valuable resource in WBANs. This makes signal interference between neighboring WBANs a serious threat because it causes energy waste in these systems. To mitigate this internetwork interference, we propose a dynamic power control mechanism in WBANs which employs reinforcement learning (RL) to learn from experience and improve its performance. This paper presents guidelines in designing efficient RL power controllers in WBANs and provides an analysis of the effect of the reward function, discount factor, learning rate and eligibility trace parameter where the main performance criteria used are convergence and solution optimality in terms of throughput and energy consumption per bit. © 2012 IEEE.

Kazemi, R, Vesilo, R, Dutkiewicz, E & Ren Ping Liu 1970, 'Reinforcement learning in power control games for internetwork interference mitigation in Wireless Body Area Networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, pp. 256-262.
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A major cause of energy waste in wireless networks is the interference between nodes working in the same frequency band. This problem appears to be more serious in Wireless Body Area Networks (WBANs) in which energy is the most valuable resource. In order to cope with this issue, power control techniques can be employed. Amongst potential approaches, those with intelligence which allow WBANs to improve their performance by learning from experience can remarkably increase flexibility and adaptability. Besides, approaches with less inter-node negotiation and cooperation are more attractive in WBANBs due to their low overhead and superior scalability. In this paper, we propose a power controller which employs Reinforcement Learning (RL) to enable WBANs to learn from experience and coordinate their power levels in a distributed manner with no inter-node negotiation and cooperation. We evaluate the performance of the proposed power controller with different RL algorithms and compare them to a counterpart approach based on game theory without learning. Their performances are evaluated in terms of optimality of the solution and convergence. We show that the RL-based power controller can trade off throughput for transmission power level and achieve lower energy consumption compared to the counterpart game. © 2012 IEEE.

Lai, J, Dutkiewicz, E, Liu, RP, Vesilo, R & Zheng, C 1970, 'Dynamic spectrum access with two channel sensing in cognitive radio networks', 2012 IEEE International Conference on Communications (ICC), ICC 2012 - 2012 IEEE International Conference on Communications, IEEE, Ottawa, ON, Canada, pp. 1757-1762.
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In this paper we present a novel dynamic spectrum sensing and access model in cognitive radio networks. This model allows secondary users (SUs) to sequentially sense two channels in a single time slot and provides coordinated access of multiple SUs to the available channels. The presented access model is formulated as a channel assignment optimization problem which is shown to be NP-hard. We subsequently propose and analyze a Markov chain based greedy channel assignment scheme (MCGA) which allows for sequential sensing of two channels with a priority order per time slot. Finally, we analyze and evaluate the performance of our approach in a saturated network. Our analytical results, validated by simulation, indicate that compared to the existing work, our approach can achieve significant improvements in terms of SU throughput and MAC delay. © 2012 IEEE.

Lai, J, Dutkiewicz, E, Ren Ping Liu & Vesilo, R 1970, 'Cooperative sensing with detection threshold optimization in cognitive radio networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 781-786.
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Spectrum sensing is a key enabling technology for cognitive radio networks where secondary users (SUs) are allowed to opportunistically utilize the potentially unused frequency band without causing harmful interference to the licensed users. Cooperative spectrum sensing has been proposed to significantly improve spectrum sensing accuracy by taking advantage of the cooperation among geographically distributed multiple SUs. In this paper, we present a cooperative spectrum sensing model with an individual energy detection threshold for each SU and formulate cooperative spectrum sensing as a nonlinear optimization problem to minimize the probability of false alarm subject to the constraint of missed detection probability. We then propose a suboptimal scheme based on a heuristic algorithm by assigning a distinct detection threshold to each individual cooperative spectrum sensing SU. Numerical results show that given a threshold of missed detection probability, the proposed scheme compared with the existing work can achieve a significant reduction in the false alarm probability, indicating that more spectrum opportunities can be identified by SUs. © 2012 IEEE.

Le, TM, Liu, RP & Hedley, M 1970, 'Rogue access point detection and localization', 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC), 2012 IEEE 23rd International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC 2012), IEEE, Sydney, NSW, Australia, pp. 2489-2493.
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The threat of rogue Access Points (APs) has attracted significant attentions from both industrial and academic researchers. However existing solutions focus on rogue AP detection, rather than localization. We propose a Rogue AP Detection and Localization (RAPDL) architecture, which integrates rogue AP detection and localization into one software system. A RAPDL demonstration system has been developed in our laboratory. In the RAPDL system, the monitors identify potential rogue APs, measure their properties and report relevant information to the server. The RAPDL server collects information from all monitors, and runs a localization algorithm to identify and locate the rogue APs. We implemented two localization algorithms in the RAPDL system based on received signal strength (RSS) and compare their performance. Experimental results acquired in an office environment show that RAPDL can detect and locate rogue APs quickly and accurately. © 2012 IEEE.

LingYun Lu & RenPing Liu 1970, 'Cooperative congestion control in multi-level InterWeave routers', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 901-906.
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Next generation data centers and cloud computing architectures require high data rates of the order of 100 Gbps from the Internet. However, most routers are typically implemented as clusters of computer and line cards, where it is difficult to allocate bandwidth and to guarantee flow fairness. In this paper, we present a cooperative congestion control scheme in the multi-level InterWeave routers with non-blocking switch fabric. The proposed scheme can provide differentiated services according to the allocated bandwidth, and can also automatically increase the bandwidth allocation of existing traffics classes. In particular, a novel AQM (Active Queue Management) algorithm is adopted in the forwarding board to guarantee the UDP flow fairness. Our simulations under two different network architectures demonstrate that the novel cooperation congestion control can achieve better fairness and data flow protection. © 2012 IEEE.

Maali, Y, Rafiei, A, Abolhasan, M, Franklin, D & Safaei, F 1970, 'A Fuzzy Logic Node Relocation Model in WSNs', 6TH INTERNATIONAL CONFERENCE ON SIGNAL PROCESSING AND COMMUNICATION SYSTEMS (ICSPCS'2012), International Conference on Signal Processing and Communication Systems, IEEE, Gold Coast, Australia, pp. 1-6.
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Hostile and harsh environments may preclude the possibility of manual redeployment of new sensor nodes, especially in the areas suffering from widespread damage and unbalanced node deployments. Distributed local relocations of currently deployed nodes is one promising solution to this problem. By using expected global node density and force-based movement algorithms inspired by the laws of nature, it is possible to address the aforementioned challenge. Force-based movement algorithms steer nodes towards their new locations based on the aggregation of exerted virtual forces on the node from their neighborhood. Some implicit assumptions about nodes' global status such as expected global node density are not realistic in dynamic and harsh environments. Thus, to conform to the uncertain nature and local interactions of nodes, a combination of radial-angular force fuzzy movement algorithms is suggested. The performance of the proposed model in terms of percentage of coverage, uniformity and average movement under three different boundary conditions are evaluated and compared with distributed self-spreading algorithms (DSSA). The results show that the simple fuzzy movement algorithm either outperforms or matches DSSA even if nodes don't benefit from expected global node density as in DSSA. © 2012 IEEE.

Movassaghi, S, Abolhasan, M, Lipman, J & IEEE 1970, 'Energy Efficient Thermal and Power Aware (ETPA) Routing in Body Area Networks', 2012 IEEE 23RD INTERNATIONAL SYMPOSIUM ON PERSONAL INDOOR AND MOBILE RADIO COMMUNICATIONS (PIMRC), IEEE International Symposium on Personal and Indoor Mobile Radio Conference, IEEE, Sydney, pp. 1108-1113.
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Research on routing in a network of intelligent, lightweight, micro and nano-technology sensors deployed in or around the body, namely Body Area Network (BAN), has gained great interest in the recent years. In this paper, we present an energy efficient, thermal and power aware routing algorithm for BANs named Energy Efficient Thermal and Power Aware routing (ETPA). ETPA considers a node's temperature, energy level and received power from adjacent nodes in the cost function calculation. An optimization problem is also defined in order to minimize average temperature rise in the network. Our analysis demonstrates that ETPA can significantly decrease temperature rise and power consumption as well as providing a more efficient usage of the available resources compared to the most efficient routing protocol proposed so far in BANs, namely PRPLC. Also, ETPA has a considerably higher depletion time that guarantees a longer lasting communication among nodes. © 2012 IEEE.

Movassaghi, S, Arab, P & Abolhasan, M 1970, 'Wireless technologies for Body Area Networks: Characteristics and challenges', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Queensland, Australia, pp. 42-47.
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Body Area Networks (BANs) are an exciting new networking technology expected to cause a dramatic shift on the way people think and manage their health and the way they benefit from information technology and advancements in a wide range of medical and non-medical applications. Since BANs are in the early stages of their development, a number of fundamental features and challenges need to be investigated to overcome the stringent requirements tied with this technology. Also the choice of an appropriate wireless technology is required to enable BAN systems to communicate physiological data. This paper provides an overview of existing wireless technologies applicable to BANs. The specific features of each wireless technology is described along with their major advantages, drawbacks and most appropriate application in BANs. Comparison of the described technologies are provided from different aspects of frequency range, data rate, coverage area, modulation technique and network topology.

Mudugamuwa, DJ, He, X & Jia, W 1970, 'Battle-Lemarie wavelet pyramid for improved GSM image denoising', Proceedings International Conference on Pattern Recognition, International Conference on Pattern Recognition, IEEE, Tsukuba, Japan, pp. 3156-3159.
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Removing noise from a digital image is a challenging problem. Application of Gaussian Scale Mixtures (GSM) in the wavelet domain has been reported to be one of the most effective denoising algorithms, published to date. The performance of this algorithm depends on the chosen wavelet representation. In this paper, we introduce an improved wavelet pyramid representation based on the Battle-Lemarie wavelet which favors the GSM denoising performance. We present the experimental denoising results using the proposed pyramid representation, and they outperform state-of-the-art GSM denoising results reported in the literature. © 2012 ICPR Org Committee.

Mudugamuwa, DJ, He, X & Jia, W 1970, 'Efficient Super-Resolution by Finer Sub-Pixel Motion Prediction and Bilateral Filtering', 2012 IEEE International Conference on Multimedia and Expo, 2012 IEEE International Conference on Multimedia and Expo (ICME), IEEE, Melbourne, Australia, pp. 800-805.
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Super-resolution reconstruction produces high-resolution images from a set of low-resolution images of the same scene. In the last two and a half decades, many super-resolution algorithms have been proposed. These algorithms are very sensitive to their assumed models of motion and noise, and computationally expensive for many practical applications. In this paper we adopt earlier reported fast prediction based sub-pixel motion estimation and a novel interpolation scheme based on the bilateral filter to produce a fast color super-resolution reconstruction that can accommodate arbitrary local motion patterns. The proposed algorithm exploits photometric proximity and available finer fractional motion information in the high resolution grid, to reconstruct enhanced super-resolved image frames. Experiments show a PSNR performance comparable to the state-of-the-art but at a fraction of their computational cost. © 2012 IEEE.

Mukunthan, A, Cooper, C, Safaei, F, Franklin, D, Abolhasan, M & IEEE 1970, 'Studying the Impact of the CORNER Propagation Model on VANET Routing in Urban Environments', 2012 IEEE VEHICULAR TECHNOLOGY CONFERENCE (VTC FALL), IEEE Vehicular Technology Conference, IEEE, Québec City, QC, Canada, pp. 1-5.
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Nguyen, DN & Krunz, M 1970, 'Power-efficient spatial multiplexing for multiantenna MANETs', 2012 IEEE International Conference on Communications (ICC), ICC 2012 - 2012 IEEE International Conference on Communications, IEEE, Ottawa, ON, Canada, pp. 4016-4020.
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We consider the problem of minimizing network's transmit power for given transmission rate demands of all links in a multi-input multi-output (MIMO) ad hoc network. The problem is nonconvex, hence, challenging to be solved, even in a centralized manner. To derive a distributed solution, we reformulate the problem as a noncooperative game. We then propose a network interference function (NIF) that captures the total interference incurred at unintended receivers by all transmitters. The proposed NIF sets the light for designing transmitter-dependent pricing policies for the above game. A price-based iterative water-filling algorithm (PIWF) is proposed to find MIMO precoding matrices, which determines both beam directions and transmission power allocation among antennas (or data streams) at each transmitter. Simulations show that PIWF is more power-efficient than all existing MIMO precoding methods. Additionally, NIF under PIWF is also the least. Simulations also show the fast convergence of PIWF. © 2012 IEEE.

Nguyen, DN & Krunz, M 1970, 'Spectrum management and power allocation in MIMO cognitive networks', 2012 Proceedings IEEE INFOCOM, IEEE INFOCOM 2012 - IEEE Conference on Computer Communications, IEEE, Orlando, FL, USA, pp. 2023-2031.
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We consider the problem of maximizing the throughput of a multi-input multi-output (MIMO) cognitive radio (CR) network. CR users are assumed to share the available spectrum without disturbing primary radio (PR) transmissions. With spatial multiplexing performed over each frequency band, a multi-antenna CR node controls its antenna radiation patterns and allocates power for each data stream by appropriately adjusting its precoding matrix. Our objective is to design a set of precoding matrices (one for each band) at each CR node so that power and spectrum are optimally allocated for that node (in terms of throughput) and its interference is steered away from other CR and PR transmissions. In other words, the problems of power, spectrum and interference management are jointly investigated. We formulate a multi-carrier MIMO network throughput optimization problem subject to frequency-dependent power constraints. The problem is non-convex, with the number of variables growing quadratically with the number of antenna elements. Such a problem is difficult to solve, even in a centralized manner. To tackle it, we translate it into a noncooperative game and derive an optimal pricing policy for each node, which adapts to the node's neighboring conditions and drives the game to a Nash-Equilibrium (NE). The network throughput under this NE is at least equal to that of a locally optimal solution of the non-convex centralized problem. To find the set of precoding matrices at each node (the best response), a low-complexity distributed algorithm is developed by exploiting the strong duality of the per-user convex optimization problem. The number of variables in the distributed algorithm is independent of the number of antenna elements. A centralized (cooperative) algorithm is also developed, serving as a performance benchmark. Simulations show that the network throughput under the distributed algorithm converges rapidly to that of the centralized one. The fast convergence of the ...

Nikodem, J, Klempous, R, Nikodem, M & Chaczko, Z 1970, 'Neighbors cooperation in WSN based on collective decisions', 2012 IEEE 16th International Conference on Intelligent Engineering Systems (INES), 2012 IEEE 16th International Conference on Intelligent Engineering Systems (INES), IEEE, Lisbon, pp. 139-143.
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The paper describes the concept of neighborhood cooperation in context of the Wireless Sensor Network, in which each node can identify and communicate with neighbors around it. The innovative spatial routing scheme shapes an area where the packet retransmission toward the base station can take effect. In this work, the retransmission rules that use notion of actions limited to node's neighborhood are determined. The proposed solution based on collective cooperation within neighborhood to support routing decisions was implemented and tested in Matlab environment. The simulation results show an improvement in the network adaptability to disturbances and as well as to changes of propagation conditions in the environment.

Odeh, N, Abolhasan, M, Safaei, F & Franklin, DR 1970, 'On the impact of RD link in resource allocation for multi-cell OFDMA cooperative relay networks with partial CSI.', ISCIT, International Symposium on Communications and Information Technologies, IEEE, Gold Coast, QLD, pp. 690-695.
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is paper investigates the impact of the relay-to-destination channel gain on subcarrier allocation for uplink OFDMA based cooperative relay networks using multiple amplify-and- forward (AF) relaying protocols. The closed form outage probability is derived for the system under partial channel state information (PCSI) and considering the presence of intercell interference (ICI). The results show that the impact of the link between the relay station and the destination is very low when the ICI is high. Hence, under this condition, the channel information of this link can be ignored during the resource allocation which significantly reduces the complexity of the resource allocation processes. Furthermore, this paper quantifies the level of interference at which the RD link can be ignored.

Orgerie, A-C, Gonçalves, P, Davis, M, Ridoux, J & Veitch, D 1970, 'Distributed Simulation and Visualization of Unsteady Flows in a Transcontinental Context', Supercomputing.

Orgerie, A-C, Gonçalves, P, Imbert, M, Ridoux, J & Veitch, D 1970, 'Survey of Network Metrology Platforms', 2012 IEEE/IPSJ 12th International Symposium on Applications and the Internet, 2012 IEEE/IPSJ 12th International Symposium on Applications and the Internet (SAINT), IEEE, Izmir, Turkey, pp. 220-225.
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Peng, Y, Jin, JS, Luo, S, Xu, M & Cui, Y 1970, '3D Pose Estimation of Front Vehicle Towards a Better Driver Assistance System', 2012 IEEE International Conference on Multimedia and Expo Workshops, 2012 IEEE International Conference on Multimedia & Expo Workshops (ICMEW), IEEE, Melbourne Australia, pp. 522-527.
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Driver assistance system enhances traffic safety and efficiency. Accurate 3D pose of front vehicle can help driver to make right decisions on road. We propose a novel real-time system to estimate 3D pose of the front vehicle. This system consists of two parallel threads: vehicle rear tracking and mapping. Vehicle rear is firstly identified in the video captured by an on-board camera, after license plate localization and foreground extraction. 3D pose estimation technique is then employed with respect to extracted vehicle rear. Most 3D pose estimation techniques need prior models or a stereo initialization with user cooperation. It is extremely difficult to obtain prior models due to various appearances of vehicle rears. Moreover, it is unsafe to ask for driver's cooperation when vehicle is running. In our system, two initial key frames for stereo algorithm are automatically extracted by vehicle rear detection and tracking. Map points are defined as a collection of point features extracted from vehicle rear with their 3D information. These map points are inferences that relating 2D features detected in following vehicle rears with 3D world. Relative 3D Pose between current vehicle rear and on-board camera is then estimated through mapping that matches map points with current point features. We demonstrate the abilities of our system by augmented reality, which needs accurate and real-time 3D pose estimation. © 2012 IEEE.

Peng, Y, Jin, JS, Luo, S, Xu, M & Cui, Y 1970, 'Vehicle Type Classification Using PCA with Self-Clustering', 2012 IEEE International Conference on Multimedia and Expo Workshops, 2012 IEEE International Conference on Multimedia & Expo Workshops (ICMEW), IEEE, Melbourne, Australia, pp. 384-389.
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Different conditions, such as occlusions, changes of lighting, shadows and rotations, make vehicle type classification still a challenging task, especially for real-time applications. Most existing methods rely on presumptions on certain conditions, such as lighting conditions and special camera settings. However, these presumptions usually do not work for applications in real world. In this paper, we propose a robust vehicle type classification method based on adaptive multi-class Principal Components Analysis (PCA). We treat car images captured at daytime and night-time separately. Vehicle front is extracted by examining vehicle front width and the location of license plate. Then, after generating eigenvectors to represent extracted vehicle fronts, we propose a PCA method with self-clustering to classify vehicle type. The comparison experiments with the state of art methods and real-time evaluations demonstrate the promising performance of our proposed method. Moreover, as we do not find any public database including sufficient desired images, we built up online our own database including 4924 high-resolution images of vehicle front view for further research on this topic. © 2012 IEEE.

Peng, Y, Jin, JS, Luo, S, Xu, M & Cui, Y 1970, 'VEHICLE TYPE CLASSIFICATION USING PCA WITH SELF-CLUSTERING', 2012 IEEE International Conference on Multimedia and Expo Workshops (ICME), 2012 IEEE International Conference on Multimedia and Expo Workshops, IEEE Computer Society, Melbourne Australia, pp. 384-389.
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Different conditions, such as occlusions, changes of lighting, shadows and rotations, make vehicle type classification still a challenging task, especially for real-time applications. Most existing methods rely on presumptions on certain conditions, such as lighting conditions and special camera settings. However, these presumptions usually do not work for applications in real world. In this paper, we propose a robust vehicle type classification method based on adaptive multi-class Principal Components Analysis (PCA). We treat car images captured at daytime and night-time separately. Vehicle front is extracted by examining vehicle front width and the location of license plate. Then, after generating eigenvectors to represent extracted vehicle fronts, we propose a PCA method with self-clustering to classify vehicle type. The comparison experiments with the state of art methods and real-time evaluations demonstrate the promising performance of our proposed method. Moreover, as we do not find any public database including sufficient desired images, we built up online our own database including 4924 high-resolution images of vehicle front view for further research on this topic

Peng, Y, Luo, S, Xu, M, Ni, Z, Jin, J, Wang, J & Zhao, G 1970, 'Bag of Features using sparse coding for gender classification', Proceedings of the 4th International Conference on Internet Multimedia Computing and Service, ICIMS 2012, ACM, Wuhan, China, pp. 80-83.
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Gender classification is challenging. Methods for gender classification need to discriminate subtle differences between male and female. Bag-of-Features (BoF) method with sparse coding has been proven very powerful in image classification. In this paper, we apply BoF method for gender classification. We use two sets of images: training images and testing images. All images are represented by a set of Scale-Invariant Feature Transform (SIFT) descriptors. In training stage, using sparse coding, Visual Words Dictionary (VWD) is constructed from SIFT descriptors extracted from training images. In testing, SIFT descriptors of testing images are approximated by visual words in VWD. The choices of approximating visual words determine the classification decision. We apply our method and another two popular methods on public dataset for gender classification. We achieved promising results.

Peng, Y, Luo, S, Xu, M, Ni, Z, Jin, JS, Wang, J & Zhao, G 1970, 'Bag of features using sparse coding for gender classification', Proceedings of the 4th International Conference on Internet Multimedia Computing and Service, ICIMCS '12: The 4th International Conference on Internet Multimedia Computing and Service, ACM, Wuhan, China, pp. 80-83.
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Gender classification is challenging. Methods for gender classification need to discriminate subtle differences between male and female. Bag-of-Features (BoF) method with sparse coding has been proven very powerful in image classification. In this paper, we apply BoF method for gender classification. We use two sets of images: training images and testing images. All images are represented by a set of Scale-Invariant Feature Transform (SIFT) descriptors. In training stage, using sparse coding, Visual Words Dictionary (VWD) is constructed from SIFT descriptors extracted from training images. In testing, SIFT descriptors of testing images are approximated by visual words in VWD. The choices of approximating visual words determine the classification decision. We apply our method and another two popular methods on public dataset for gender classification. We achieved promising results. Copyright © 2012 ACM.

Peng, Y, Xu, M, Ni, Z, Jin, JS & Luo, S 1970, 'Accurate Pedestrian Counting System Based on Local Features', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), Pacific-Rim Conference on Multimedia, Springer Berlin Heidelberg, Singapore, pp. 850-860.
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Accurate pedestrian counting are challenging in real-world due to occlusions, pedestrians' overlays or camera view sensitive. In this paper, we propose an accurate and robust pedestrian detection and counting system to address these problems. Our proposed method is group-based, where the count of people in a dense moving group is estimated as a whole. Moving groups containing single or several pedestrians are discriminated from other moving objects. Our method utilizes 9 features of each moving group within a video frame to estimate the pedestrian number in each group. Pedestrian counts are optimized by a novel tracking method, which is based on an analysis of moving groups match, split or merge. Comparison experiments with other two current methods on three benchmark surveillance videos show the effectiveness of our proposed method. © 2012 Springer-Verlag.

Pupatwibul, P, Al Sabbagh, A, Banjar, AR & Braun, RM 1970, 'Distributed Systems in Next Generation Networks', 1st Australian Conference on the Applications of Systems Engineering (ACASE'12), 1st Australian Conference on the Applications of Systems Engineering (ACASE'12), University of Technology, Sydney, Sydney, Australia, pp. 32-33.
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Qin, PY, Ding, C & Guo, YJ 1970, 'A high-gain beam-steering quasi-yagi antenna', IEEE Antennas and Propagation Society AP S International Symposium Digest, IEEE International Symposium on Antennas and Propagation, IEEE, IEEE, pp. 122-125.
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Recently, beam-steering reconfigurable antennas have gained considerable attention due to their capability of enhancing the performance of wireless communication systems [1]-[5]. By changing the main beam direction, they have the potential to avoid noise sources, to mitigate the multipath fading, to provide larger coverage, and to save energy. Unfortunately, most of the currently reported beam steering antennas suffer from either the low realized gain or the very small overlapped impedance bandwidth. In [1] and [2], rectangular single-arm spiral antennas are employed to realize beam scanning. The gains of the antennas in [1] and [2] are between 3-6 dBi and 4 dBi, respectively, and the bandwidths of the two antennas are about 6% (axial ratio bandwidth) and about 1.4% (50MHz at 3.7 GHz), respectively. In addition, a four-element L-shaped antenna array is proposed that can switch the main beam to 8 directions [3]. The gain of this design is around -0.5-2.1 dBi and the impedance bandwidth is 4% (2.42-2.54 GHz). In [4], a reconfigurable patch-slot-ring antenna is designed with both elevation and azimuth beam switching. The 6-dB impedance bandwidth for all modes is 2.6% centred at 2.05 GHz, and the measured peak gains are 6.1-6.7 dBi. Furthermore, a beam-tilting pattern reconfigurable microstrip parasitic dipole array is shown in [5] with an impedance bandwidth of 5%. The gain of this antenna is not reported. There is no doubt that the small impedance bandwidth or the low gain of the above antennas can significantly limit their applications. © 2012 IEICE.

Qin, P-Y, Guo, YJ & Dutkiewicz, E 1970, 'Experimental analysis of a polarization reconfigurable antenna for MIMO systems', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, IEEE, pp. 638-642.
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Qu, Z, Wang, J, Xu, M & Lu, H 1970, 'A Grid Based Resizing Framework via Effectively Combining Cropping with Warping', 2012 IEEE International Conference on Image Processing ICIP 2012, IEEE International Conference on Image Processing, IEEE Computer Society, Lake Buena Vista, Florida, USA, pp. 2997-3000.
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Image retargeting is a problem of adapting images to arbitrary aspect ratios in order to maximize users browsing experience. As two major solutions for image retargeting, warping and cropping have their own advantages and limitations respectively. In this paper, a grid based resizing framework is proposed for effectively combining warping with cropping. Firstly, warping preserves more important content within the cropping window through retaining the aspect ratios of salient grids and distorting the non-salient ones. Secondly, cropping provides extra space for warping to absorb the spatial deformation and assures the important content is retained in retargeted image simultaneously. Finally the objective function is formulated as two energy terms for warping and cropping respectively. And, a nonlinear optimization is applied to obtain the retargeting results. Our approach could make warping and cropping complement each other, and improve the quality of retargeted image effectively. Experiments and comparisons on the ReTargetMe dataset demonstrate the superiority of our approach.

Raduescu, C & Gill, AQ 1970, 'Handling the Complexity of ISD Projects with Agile Methods: A Conceptual Foundation.', ISD, International Conference on Information Systems Development, Springer, Prato Centre, Italy, pp. 417-427.
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Traditional approaches to software and information systems development (ISD) cannot fulfill the challenges presented by the complexity inherent in todays dynamic and changing environments. In this study we argue that ISD projects are socially complex endeavors and suggest that agile development methods display characteristics that justify them as being appropriate for such project environments. We suggest that one theory that justifies the appropriateness of agile methods in such contexts is the complex adaptive systems (CAS) theory. We first argue that ISD projects can be treated as CAS, and second, we assess the alignment between CAS characteristics and agile methods principles. We therefore propose and discuss a preliminary conceptual foundation for handling the complexity of ISD projects with agile methods. Our future research directions seek to investigate the applicability of specific agile methods and develop a comprehensive framework that will offer a validated theoretical justification of better approaches to manage complex ISD projects in practice.

Rafiei, A, Abolhasan, M, Franklin, DR & Safaei, F 1970, 'WSNs Coverage Hole Partial Recovery by Nodes' Constrained and Autonomous Movements Using Virtual alpha-chords', ICWMC 2012, The Eighth International Conference on Wireless and Mobile Communications, International Conference on Wireless and Mobile Communications (ICWMC), XPS (Xpert Publishing Services) / IARIA, Venice, pp. 74-80.

Sabbagh, AAL, Braun, R & Abolhasan, M 1970, 'A mobility optimization CRRM approach for Next Generation Wireless Networks', 2012 International Conference on Computer & Information Science (ICCIS), 2012 International Conference on Computer & Information Science (ICCIS), IEEE, Kuala Lumpur, Malaysia, pp. 609-613.
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Next Generation Wireless Networks (NGWN) are predicted to be heterogeneous in nature. This is achieved through the integration of different Radio Access Technologies (RATs) over a common platform. Common Radio Resource Management (CRRM) was proposed to manage radio resource utilization in heterogeneous wireless networks and to provide required Quality of Service (QoS) for allocated calls. RAT selection algorithms are an integral part of the CRRM algorithms. Their role is to decide, when a new or Vertical Handover (VHO) call is requested, which of the available RATs is most suitable to fit the need of the incoming call and when to admit them. In this paper, we propose an intelligent hybrid RAT selection approach for mobility optimization (patent pending) which includes sorting available RATs, collecting information on each RAT using the IEEE P1900.4 Protocol, and making decisions for selecting the most suitable RAT for incoming calls. A comparison for the performance of centralized load-balancing, distributed and the proposed mobility optimization algorithms is presented in terms of new calls blocking probability, VHO calls dropping probability and satisfactions probability. Simulation results show that the proposed algorithm performs better than the centralized load-balancing and distributed algorithms in terms of blocking, dropping and satisfactions probabilities. © 2012 IEEE.

Saito, K, Kitao, K, Imai, T & Miura, S 1970, 'Human-body shadowing modeling for indoor quasi-static MIMO channels', ISAPE2012, 2012 10th International Symposium on Antennas, Propagation & EM Theory (ISAPE - 2012), IEEE, Kuala Lumpur, Malaysia, pp. 608-611.
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Massive MIMO can dramatically improve capacity and spectral efficiency. However, it is not very clear whether it can significantly improve the signal blockage problem that exists in single antenna systems. In this paper, we investigate the impact of the human body on indoor massive MIMO channels, using practically measured channel data for a 32x8 massive MIMO system in a complex office environment. We introduce a parameter of Power Imbalance (PI) indices to estimate the wide-sense none-stationarity in multiple domains and another parameter of Channel Popularity Indices (CPI) to predict the popularity of MIMO channel. We find that in most cases, the presence of the human body still has a non- negligible negative impact. It decreases the ergodic capacity by about 8% and increases the path loss exponent by 1. In average, the ergodic capacity for NLOS channels are 15% higher than that for LOS.

Salman, N, Guo, YJ, Kemp, AH & Ghogho, M 1970, 'Analysis of linear least square solution for RSS based localization', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 1051-1054.
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Positioning of wireless devices has received a great deal of interest from researchers in the last decade. In order to locate nodes in low complexity and power efficient networks, the received signal strength (RSS) based positioning systems have been the center of focus. RSS based localization needs no additional hardware and hence is favored for low complexity and cheap localization networks. A major source of error in RSS location estimation is due to shadowing effects in multipath wireless channels. In this paper we analyze the performance of RSS location estimator based on the linear least square approach. We derive expressions for mean square error (MSE) and bias of location estimates. The theoretical analysis is compared with simulation results and it is observed that the analysis accurately predicts the performance of the location estimation. We also discuss the impact of reference node placement on estimation bias. © 2012 IEEE.

Shariati, N, Rowe, WST, Ghorbani, K & IEEE 1970, 'RF Field Investigation and Maximum Available Power Analysis for Enhanced RF Energy Scavenging', 2012 42ND EUROPEAN MICROWAVE CONFERENCE (EUMC), Conference on European Microwave Week Connecting the World, pp. 329-332.
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RF energy harvesting is attracting widespread interest to meet the goal of providing sustainable energy sources for future growth and protection of the environment. In order to demonstrate the feasibility of RF energy harvesting, RF field investigations and analysis of maximum available power in the suburbs of Melbourne, Australia are conducted. Measurement results and analysis indicate that broadcasting system at 540 MHz (with 20 MHz bandwidth) and 100 MHz (88-108 MHz) are great scavenging sources. These frequency ranges provide stable RF signal levels and low propagation loss, produce maximum available power to a range of locations. In addition, broadcasting bands offer a great deal of flexibility to deploy simple and cost-effective implementations, which is of paramount importance for optimal power harvesting systems. © 2012 EUROPEAN MICROWAVE ASSOC.

Shen, Y, Miao, Z & Zhang, J 1970, 'Unsupervised online learning trajectory analysis based on weighted directed graph', Proceedings International Conference on Pattern Recognition, International Conference on Pattern Recognition, IEEE, Tsukuba, Japan, pp. 1306-1309.
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In this paper, we propose a novel unsupervised online learning trajectory analysis method based on weighted directed graph. Each trajectory can be represented as a sequence of key points. In the training stage, unsupervised expectation-maximization algorithm (EM) is applied for training data to cluster key points. Each class is a Gaussian distribution. It is considered as a node of the graph. According to the classification of key points, we can build a weighted directed graph to represent the trajectory network in the scene. Each path is a category of trajectories. In the test stage, we adopt online EM algorithm to classify trajectories and update the graph. In the experiments, we test our approach and obtain a good performance compared with state-of-the-art approaches. © 2012 ICPR Org Committee.

Shoujun Huang, Yongtao Su, Ying He & Shan Tang 1970, 'Joint time and frequency offset estimation in LTE downlink', 7th International Conference on Communications and Networking in China, 2012 7th International ICST Conference on Communications and Networking in China (CHINACOM 2012), IEEE, pp. 394-398.
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Sun, X, Cui, H, Liu, R, Chen, J & Liu, Y 1970, 'Multistep ahead prediction for real-time VBR video traffic using deterministic echo state network', 2012 IEEE 2nd International Conference on Cloud Computing and Intelligence Systems, 2012 IEEE 2nd International Conference on Cloud Computing and Intelligence Systems (CCIS), IEEE, Hangzhou, China, pp. 928-931.
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Variable bit rate (VBR) video traffic, exhibiting high self-similarity and burstiness, has been a major traffic component in high speed network. However, its complex bit rate distribution makes VBR video traffic prediction, especially multistep ahead prediction, very difficult. Recently, deterministic echo state network with adjacent-feedback loop reservoir structure (ALR) was proved to have high prediction accuracy, good memory capacity, and simple structure. In the paper, we apply ALR to real-time VBR video traffic prediction. The proposed scheme makes use of loop reservoir with identity activation function to conduct sample learning in high dimension states. Experimental results show that the simplified ALR scheme can effectively capture dynamic characteristics of VBR video traffic with less training time. Its multistep prediction accuracy is improved by 2% on average, compared with the neural network based on multi-resolution learning. © 2012 IEEE.

Sun, Z, Zhong, SS, Esselle, KP, Guo, J & Cai, Y 1970, 'Broadband dual-band dual-polarized overlapped antenna element', 2012 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC), 2012 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications (APWC), IEEE, Cape Town, South Africa, pp. 223-226.
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A broadband dual-band dual-polarized (DBDP) shared-aperture array is proposed, where the novel L- and C- band overlapped stacked patches are designed as the unit cell of full array. The impedance bandwidth in the lower band is enhanced by avoiding perforation. The DBDP unit cell prototype has been fabricated to validate the overlapped-structure feasibility for phased array applications. The impedance bandwidths (|S 11 | ≤ -10dB) of 17.6% (219MHz) and 15% (790 MHz) are measured in L- and C-band, respectively, while good radiation patterns are also confirmed in both bands. © 2012 IEEE.

Tan, Z, Jamdagni, A, He, X, Nanda, P & Liu, RP 1970, 'Triangle-Area-Based Multivariate Correlation Analysis for Effective Denial-of-Service Attack Detection', 2012 IEEE 11th International Conference on Trust, Security and Privacy in Computing and Communications, 2012 IEEE 11th International Conference on Trust, Security and Privacy in Computing and Communications (TrustCom), IEEE, Liverpool UK, pp. 33-40.
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Cloud computing plays an important role in current converged networks. It brings convenience of accessing services and information to users regardless of location and time. However, there are some critical security issues residing in cloud computing, such as availability of services. Denial of service occurring on cloud computing has even more serious impact on the Internet. Therefore, this paper studies the techniques for detecting Denial-of-Service (DoS) attacks to network services and proposes an effective system for DoS attack detection. The proposed system applies the idea of Multivariate Correlation Analysis (MCA) to network traffic characterization and employs the principal of anomaly-based detection in attack recognition. This makes our solution capable of detecting known and unknown DoS attacks effectively by learning the patterns of legitimate network traffic only. Furthermore, a triangle area technique is proposed to enhance and speed up the process of MCA. The effectiveness of our proposed detection system is evaluated on the KDD Cup 99 dataset, and the influence of both non-normalized and normalized data on the performance of the detection system is examined. The results presented in the system evaluation section illustrate that our DoS attack detection system outperforms two state-of-theart approaches. © 2012 IEEE.

Tan, Z, Jamdagni, A, Nanda, P, He, X & Liu, RP 1970, 'Evaluation on multivariate correlation analysis based denial-of-service attack detection system', Proceedings of the First International Conference on Security of Internet of Things, SECURIT '12: First International Conference on Security of Internet of Things, ACM, Kollam, India, pp. 160-164.
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In this paper, a Denial-of-Service (DoS) attack detection system is explored, where a multivariate correlation analysis technique based on Euclidean distance is applied for network traffic characterization and the principal of anomaly-based detection is employed in attack recognition. The effectiveness of the detection system is evaluated on the KDD Cup 99 dataset and the influence of data normalization on the performance of attack detection is analyzed in this paper as well. The evaluation results and comparisons prove that the detection system is effective in distinguishing DoS attack network traffic from legitimate network traffic and outperforms two state-of-the-art systems. Copyright 2012 ACM.

Thilak, N & Braun, R 1970, 'Near field magnetic induction Communication in Body Area Network', 2012 International Conference on Devices, Circuits and Systems (ICDCS), 2012 International Conference on Devices, Circuits and Systems (ICDCS 2012), IEEE, Coimbatore, India, pp. 124-125.
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Next generation wireless communication system may be near filed magnetic induction Communication (NFMIC) which has major application in Body Area Network (BAN). Communication takes place in and around the body is called BAN. This Paper describes the working principle, power equation, its significance and application in NFMIC. It is compared with the other short range wireless technology such as Bluetooth, WLAN, UWB, ZigBee and RFID inside a BAN. This provides information how NFMIC is going to be next generation wireless communication. © 2012 IEEE.

Tian, XK, Chu, QX, Zhu, H & Wu, XH 1970, 'A UWB bandpass filter with wide stopband performance using cross-shaped coupled lines', 2012 International Conference on Microwave and Millimeter Wave Technology (ICMMT), 2012 International Conference on Microwave and Millimeter Wave Technology (ICMMT), IEEE, pp. 1-4.
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A novel coupling structure is presented for the design of an ultra-wideband (UWB) bandpass filter (BPF) with wide stopband performance. The proposed coupled structure is constructed by modifying the conventional one quarter-wavelength parallel coupled lines into cross-shaped coupled lines (CCLs), which results in size miniaturization as well as wide upper-stopband performance. The CCLs can be properly designed so that the unwanted passband is rejected and the transmission zeros can be assigned toward the harmonic resonances of the triple-mode resonator. By cooperating the proposed CCLs and the triple-mode resonator, a UWB BPF with sharp roll-off and improved out-of-band performance is then constructed. Both simulated and measured results are in good agreement to verify the predicted results. © 2012 IEEE.

Tushar, W, Smith, D, Lamahewa, TA & Jian Zhang 1970, 'Non-cooperative power control game in a multi-source wireless sensor network', 2012 Australian Communications Theory Workshop (AusCTW), 2012 Australian Communications Theory Workshop (AusCTW), IEEE, Wellington, New Zealand, pp. 43-48.
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In this paper, a game theoretic scheme is proposed to study power control in a multi-source (transmitting to multiple clusters) wireless sensor network. A game where each sensor chooses it's transmit power independently to achieve a target signal to interference plus noise ratio (SINR) at the master sensor in the receiving cluster is analyzed. It is shown that the game has a Nash equilibrium and it is unique under certain constraints. Numerical results are provided to show the effectiveness of the proposed game considering distance-dependent attenuation with various path loss exponents. © 2012 IEEE.

Tushar, W, Smith, DB, Zhang, A, Lamahewa, TA & Abhayapala, T 1970, 'Distributed transmit beamforming: Phase convergence improvement using enhanced one-bit feedback', 2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012 IEEE Wireless Communications and Networking Conference (WCNC), IEEE, Shanghai, China, pp. 528-532.
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Transmission of signals using multiple antennas can significantly improve the energy efficiency of a wireless network, and the proper alignment of the transmitted signals' phases at the receiver is one of the key factors so this efficiency improvement can be realized. In a time-varying channel, due to the relative motion between the transmitters and the receiver, the development of a scheme that guarantees such alignment is very challenging. In this paper, considering a distributed transmit beamforming scenario, an algorithm to achieve such phase alignment of signals in a time-varying channel is proposed. A simple formula is derived, which can be adopted by each transmitter to compute its beamforming weight's phase, and it is shown that the use of this perturbation results in a significant improvement in terms of speed of convergence at the receiver. With simulation it is shown that, using the proposed scheme, the transmitted signals' phase aligned at the receiver 33% faster than the one-bit feedback scheme. The average theoretical bit error rate is achieved 50% faster relative to the one-bit feedback scheme with on average 18% less number of antennas at the transmitter. © 2012 IEEE.

Tushar, W, Zhang, J, Smith, DB, Poor, HV, Platt, G & Durrani, S 1970, 'An efficient energy curtailment scheme for outage management in smart grid', 2012 IEEE Global Communications Conference (GLOBECOM), GLOBECOM 2012 - 2012 IEEE Global Communications Conference, IEEE, Anaheim, CA, USA, pp. 3056-3061.
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In this paper an efficient energy curtailment scheme is studied, which enables the power users of a smart grid network to decide on the reduction in energy supplied to them in the event of a power outage in the system. Considering the advantages of a two-way communications infrastructure for any future smart grid, a non-cooperative generalized Nash game is proposed where the players are users of power in the network. They adopt a strategy to choose the amount of reduction in energy supplied to them based on their energy requirements so as to minimize the total cost incurred to the system due to the power outage (i.e., social optimality). The game is modeled as a variational inequality problem, and it is shown that the socially optimum solution is obtained at the variational equilibrium of the energy curtailment game. An algorithm that enables the users to efficiently reach this equilibrium is proposed. Simulation results show that the proposed game yields an improvement of about 15% on average, in terms of average total cost reduction, compared to a standard equal power curtailment scheme. © 2012 IEEE.

Umuhoza, D & Braun, R 1970, 'Trustworthiness Assessment of Knowledge on the Semantic Sensor Web by Provenance Integration', 2012 26th International Conference on Advanced Information Networking and Applications Workshops, 2012 IEEE Workshops of International Conference on Advanced Information Networking and Applications (WAINA), IEEE, Fukuoka, Japan, pp. 387-392.
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Knowledge represented on the Semantic Sensor Web originates from different datasets which are often a collection or aggregation of other sources. The SSW is dynamic, open and distributed, so the datasets are of varying quality and completeness. Consumers need to be provided with a level of trustworthiness of this knowledge to determine its relevance and usefulness. Interpretation of provenance (detailed information about the origin of data - held in metadata) is necessary in order to analyse how knowledge came into existence and measure its trustworthiness. However there are challenges in interpreting the provenance in a uniform way, because different data providers use different processes to manipulate the data and different annotation techniques to provide metadata. Although there are methods for retrieving provenance, knowledge consumers are left with the responsibility of assessing the trustworthiness of discovered knowledge dependent on how they see it fitting their application. This paper proposes a meta-knowledge ontology to align the concepts and properties of existing provenance schemas and ontologies. The meta-provenance ontology enables common interpretation of different provenances, and hence their integration. This paper also presents a trustworthiness assessment model based on integrating provenance. This model provides a function for the knowledge consumer to choose the relevant provenance attributes and allows for ranking of their importance. This provides a reliable mechanism for measuring trustworthiness, as only attributes relevant to the consumer are used. © 2012 IEEE.

Villain, B, Davis, M, Ridoux, J, Veitch, D & Normand, N 1970, 'Probing the latencies of software timestamping', 2012 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication Proceedings, 2012 IEEE International Symposium on Precision Clock Synchronization for Measurement, Control and Communication (ISPCS), IEEE, San Francisco, CA, USA, pp. 1-6.
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Wang, S, Wu, Q, He, X & Xu, M 1970, 'On splitting dataset: Boosting Locally Adaptive Regression Kernels for car localization', 2012 12th International Conference on Control Automation Robotics & Vision (ICARCV), 2012 12th International Conference on Control Automation Robotics & Vision (ICARCV 2012), IEEE, Guangzhou, China (People's Republic of), pp. 1154-1159.
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In this paper, we study the impact of learning an Adaboost classifier with small sample set (i.e., with fewer training examples). In particular, we make use of car localization as an underlying application, because car localization can be widely used to various real world applications. In order to evaluate the performance of Adaboost learning with a few examples, we simply apply Adaboost learning to a recently proposed feature descriptor - Locally Adaptive Regression Kernel (LARK). As a type of state-of-the-art feature descriptor, LARK is robust against illumination changes and noises. More importantly, we use LARK because its spatial property is also favorable for our purpose (i.e., each patch in the LARK descriptor corresponds to one unique pixel in the original image). In addition to learning a detector from the entire training dataset, we also split the original training dataset into several sub-groups and then we train one detector for each sub-group. We compare those features associated using the detector of each sub-group with that of the detector learnt with the entire training dataset and propose improvements based on the comparison results. Our experimental results indicate that the Adaboost learning is only successful on a small dataset when those learnt features simultaneously satisfy two conditions that: 1. features are learnt from the Region of Interest (ROI), and 2. features are sufficiently far away from each other. © 2012 IEEE.

Wu, Y, Lu, S, Mei, T, Zhang, J & Li, S 1970, 'Local visual words coding for low bit rate mobile visual search', Proceedings of the 20th ACM international conference on Multimedia, MM '12: ACM Multimedia Conference, ACM, Nara, Japan., pp. 989-992.
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Mobile visual search has attracted extensive attention for its huge potential for numerous applications. Research on this topic has been focused on two schemes: sending query images, and sending compact descriptors extracted on mobile phones. The first scheme requires about 30-40KB data to transmit, while the second can reduce the bit rate by 10 times. In this paper, we propose a third scheme for extremely low bit rate mobile visual search, which sends compressed visual words consisting of vocabulary tree histogram and descriptor orientations rather than descriptors. This scheme can further reduce the bit rate with few extra computational costs on the client. Specifically, we store a vocabulary tree and extract visual descriptors on the mobile client. A light-weight pre-retrieval is performed to obtain the visited leaf nodes in the vocabulary tree. The orientation of each local descriptor and the tree histogram are then encoded to be transmitted to server. Our new scheme transmits less than 1KB data, which reduces the bit rate in the second scheme by 3 times, and obtains about 30% improvement in terms of search accuracy over the traditional Bag-of-Words baseline. The time cost is only 1.5 secs on the client and 240 msecs on the server. © 2012 ACM.

Xianjun Yang, Dutkiewicz, E, Qimei Cui, Xiaofeng Tao, Guo, YJ & Xiaojing Huang 1970, 'Compressed Network Coding for Distributed Storage in Wireless Sensor Networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 816-821.
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Distributed storage plays a very important role in Wireless Sensor Networks (WSNs), especially in catastrophic scenarios. To improve the energy efficiency of distributed storage, this paper proposes a Compressed Network Coding based Distributed Storage (CNCDS) scheme. Exploiting the correlation of sensor readings and utilizing the Compressed Sensing (CS) theory and network coding technology, the proposed CNCDS scheme achieves good energy efficiency by reducing the number of transmissions and receptions. Theoretical analysis proves that, the measurement matrix of CNCDS scheme guarantees good CS recovery performance. Simulation results show that, compared with the conventional ICStorage scheme, the proposed CNCDS scheme reduces the number of transmissions, the number of receptions and the CS recovery mean squared error (MSE) by up to 55%, 74% and 76% respectively. In contrast to the conventional NICStorage scheme, the proposed CNCDS scheme can simultaneously reduce the number of transmissions, receptions and recovery MSE. © 2012 IEEE.

Xu, J, Wu, Q, Zhang, J & Tang, Z 1970, 'Object Detection Based on Co-occurrence GMuLBP Features', 2012 IEEE International Conference on Multimedia and Expo, 2012 IEEE International Conference on Multimedia and Expo (ICME), IEEE, 2012 IEEE International Conference on Multimedia and Expo, pp. 943-948.
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Image co-occurrence has shown great powers on object classification because it captures the characteristic of individual features and spatial relationship between them simultaneously. For example, Co-occurrence Histogram of Oriented Gradients (CoHOG) has achieved great success on human detection task. However, the gradient orientation in CoHOG is sensitive to noise. In addition, CoHOG does not take gradient magnitude into account which is a key component to reinforce the feature detection. In this paper, we propose a new LBP feature detector based image co-occurrence. Building on uniform Local Binary Patterns, the new feature detector detects Co-occurrence Orientation through Gradient Magnitude calculation. It is known as CoGMuLBP. An extension version of the GoGMuLBP is also presented. The experimental results on the UIUC car data set show that the proposed features outperform state-of-the-art methods. © 2012 IEEE.

Xu, KC, Dutkiewicz, E, Huang, X & Guo, YJ 1970, 'Ranging based positioning employing co-operative arrays', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 1055-1059.
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A novel wireless positioning method employing an array of sensors which are capable of doing range estimates is proposed. Collectively, all the sensors in the sensor array can produce the direction of arrival (DoA) and the range information of mobile targets. To improve the positioning accuracy, it is proposed to introduce co-operations between the sensor arrays. Theoretical analysis and simulation results show that the use of the co-operation can increase the positioning accuracy significantly. Compared with other known methods, the proposed method does not require any phase measurement in the sensor arrays, so the system is relatively easy to operate and maintain. © 2012 IEEE.

Yang, X, Guo, YJ, Cui, Q, Tao, X & Huang, X 1970, 'Random circulant orthogonal matrix based Analog Compressed Sensing', 2012 IEEE Global Communications Conference (GLOBECOM), GLOBECOM 2012 - 2012 IEEE Global Communications Conference, IEEE, Anaheim, CA, pp. 3605-3609.
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Analog Compressed Sensing (CS) has attracted considerable research interest in sampling area. One of the promising analog CS technique is the recently proposed Modulated Wideband Converter (MWC). However, MWC has a very high hardware complexity due to its parallel structure. To reduce the hardware complexity of MWC, this paper proposes a novel Random Circulant Orthogonal Matrix based Analog Compressed Sensing (RCOM-ACS) scheme. By circularly shifting the periodic mixing function, the RCOM-ACS scheme reduces the number of physical parallel channels from m to 1 at the cost of longer processing time, where m is in the order of several dozen to several hundred in MWC. It is proved that the m×M measurement matrix of RCOM-ACS scheme satisfies the Restricted Isometry Property (RIP) condition with probability 1-M -O(1) when m = O(rlog2Mlog3r), where M is the length of the periodic mixing function, r denotes the sparsity of the input signal. Furthermore, to make a good tradeoff between processing time and hardware complexity, a short processing time RCOM-ACS scheme is proposed in this paper. Simulation results show that, the proposed schemes outperform MWC in terms of recovery performance. © 2012 IEEE.

Yang, X, Liu, RP & Hedley, M 1970, 'A channel access cycle based model for IEEE 802.11e EDCA in unsaturated traffic conditions', 2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012 IEEE Wireless Communications and Networking Conference (WCNC), IEEE, Paris, FRANCE, pp. 1496-1501.
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Yang, Y, Shen, D, Dutkiewicz, E & Fang, G 1970, 'Channel model for in-body WBAN', Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation, 2012 IEEE Antennas and Propagation Society International Symposium and USNC/URSI National Radio Science Meeting, IEEE, pp. 1-2.
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This paper presents an experimental investigation into the in-body channel in 400 MHz MICS Band. By taking into account the joint effect of human movement and multipath effects, the measurements have been conducted in a populated office at very short distances. The dynamic channel behaviour has been captured and based on the statistical analyses of fading duration, a six-state Semi-markov model that considers both Line of Sight (LOS) and Non Line of Sight (NLOS) cases is proposed. Parameters of the Semi-markov model are estimated from the measured data. The validity of this model is confirmed by comparison of the first order and second order statistics of the proposed model with the measured data. © 2012 IEEE.

Yihuai Yang, Gengfa Fang, Dutkiewicz, E & Dongya Shen 1970, 'Statistical characterization of the 400 MHz in-body propagation channel in in-door environments', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 48-53.
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Channel modeling is the starting point of effective, efficient body-centric communications. Many efforts [2]-[6] have been made to characterize the on-body area propagation channel in static scenarios at various frequency bands in an anechoic chamber. This paper presents an experimental investigation into the in-body channel in 400 MHz MICS Band. By taking into account the joint effect of human movement and multipath effects, the measurements have been conducted in a populated office at very short distances. The dynamic channel behaviour has been captured and based on the statistical analyses of fading duration, a six-state Semi-markov model that considers both Line of Sight (LOS) and Non Line of Sight (NLOS) cases is proposed. Parameters of the Semi-markov model are estimated from the measured data. The validity of this model is confirmed by comparison of the first order and second order statistics of the proposed model with the measured data. © 2012 IEEE.

Yu, K & Dutkiewicz, E 1970, 'CRLB derivation for mobile tracking in NLOS propagation environments', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD Australia, pp. 1148-1153.
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This article presents theoretical analysis for mobile tracking in non-line-of-sight (NLOS) propagation environments. With some approximations concise analytical formulas are derived for the Cramer-Rao lower bound (CRLB) for positioning when measurements of distance, heading angle, and velocity are employed to estimate the mobile position. The derived lower bound can be used as a reference for the evaluating of various mobile tracking algorithms in NLOS scenarios. © 2012 IEEE.

Yu, K & Dutkiewicz, E 1970, 'Improved Kalman filtering algorithms for mobile tracking in NLOS scenarios', 2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012 IEEE Wireless Communications and Networking Conference (WCNC), IEEE, Shanghai, China, pp. 2390-2394.
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This paper presents an improved positioning approach for cellular-network based mobile tracking in severe non-line-of-sight (NLOS) propagation environments. The proposed approach consists of two stages: the smoothing stage to suppress the NLOS errors in the distance measurements; and the position tracking stage. An improved distance smoothing method is proposed to significantly reduce the NLOS errors. It applies online distance mean and variance estimates to identify LOS and NLOS propagations. The online LOS and NLOS identification results, the distance mean and variance estimates are employed to update the Kalman filter (KF) for smoothing distance measurements. A data fusion technique is developed to combine distance measurements, mobile velocity and heading angle estimates provided by motion sensors through the extended KF. Simulation results demonstrate that the proposed two-stage approach significantly improves position accuracy compared to the existing NLOS mitigation algorithms, at the cost of increased computational complexity. © 2012 IEEE.

Yu, Y, Dutkiewicz, E, Huang, X & Mueck, M 1970, 'A resource allocation scheme for balanced performance improvement in LTE networks with inter-cell interference', 2012 IEEE Wireless Communications and Networking Conference (WCNC), 2012 IEEE Wireless Communications and Networking Conference (WCNC), IEEE, Shanghai, China, pp. 1630-1635.
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In this paper we propose a novel resource allocation scheme to achieve a balanced performance improvement for all users in a LTE network subject to inter-cell interference. In the proposed scheme the resource allocation process is implemented in two steps. In the first step interference coordination and scheduling are first conducted in a global manner to prevent cell-edge users from mutual interference. In the second step, optimal power allocation is conducted to maximize performance of cell-edge users while maintaining high performance of cell-center users. The optimal power allocation problem is solved using the Lagrange decomposition method. Simulation results show that our proposed scheme can significantly improve performance for all users in a multi-cell network and achieve a better performance balance between cell-edge and cell-center users. © 2012 IEEE.

Yu, Y, Dutkiewicz, E, Huang, X & Mueck, M 1970, 'Adaptive power allocation for soft frequency reuse in multi-cell LTE networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 991-996.
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This paper presents a novel power allocation approach for soft frequency reuse (SFR) adopted in a multi-cell LTE network. Based on the fact that major inter-cell interference (ICI) is coordinated by SFR, the proposed power allocation focuses on dealing with mutual interference between cell-edge and cell-center users in the network. It is formulated as an optimization problem, where the performance of cell-edge users is optimized under the condition that desirable performance must be maintained for cell-center users. The optimal solution can be obtained by using the Lagrange decomposition method. Simulation results show that our approach can significantly improve performance of cell-edge users by achieving 20% gain over conventional SFR with average power allocation when higher performance for cell-center users is maintained. © 2012 IEEE.

Zare Borzeshi, E, Perez Concha, O & Piccardi, M 1970, 'Human Action Recognition in Video by Fusion of Structural and Spatio-temporal Features', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), Joint IAPR International Workshop on SSPR & SPR, Springer Berlin Heidelberg, Hiroshima, Japan, pp. 474-482.
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The problem of human action recognition has received increasing attention in recent years for its importance in many applications. Local representations and in particular STIP descriptors have gained increasing popularity for action recognition. Yet, the main limitation of those approaches is that they do not capture the spatial relationships in the subject performing the action. This paper proposes a novel method based on the fusion of global spatial relationships provided by graph embedding and the local spatio-temporal information of STIP descriptors. Experiments on an action recognition dataset reported in the paper show that recognition accuracy can be significantly improved by combining the structural information with the spatio-temporal features. © 2012 Springer-Verlag Berlin Heidelberg.

Zeng, C, Jia, W & He, X 1970, 'An Algorithm for Colour-Based Natural Scene Text Segmentation', Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics), International conference on Camera-Based Document Analysis and Recognition, Springer Berlin Heidelberg, China, pp. 58-68.
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Before the step for text recognition, a text image needs to be segmented into foreground containing only the text area and background. In this paper, a method is proposed for segmenting colour natural scene texts which suffer from a wide range of degradations with complex background. A text image is firstly processed by two 3-means clustering operations with different distance measurements. Then, a modified connected component (CC)-based validation method is used to obtain the text area after clustering. Thirdly, a proposed objective segmentation evaluation method is utilised to choose the final segmentation result from the two segmented text images. The proposed method is compared with other existing methods based on the ICDAR2003 public database. Experimental results show the effectiveness of the proposed method. © 2012 Springer-Verlag Berlin Heidelberg.

Zhang, J, Schonfeld, D & Feng, DD 1970, 'Message from ICME 2012 General Chairs', 2012 IEEE International Conference on Multimedia and Expo Workshops, 2012 IEEE International Conference on Multimedia & Expo Workshops (ICMEW 2012), IEEE, pp. xiv-xv.
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ICME 2012 is the thirteen in the series of ICME conferences that has been held annually since 2000, in various cities throughout the world. The success of this conference would not have been possible without the generous help of sponsors. Paper prizes and Student Travel Grants are sponsored by the National Information and Communications Technology Australia (NICTA), Microsoft Research, IBM Research, Canon Information Systems Research Australia (CiSRA), and Advanced Analytics Institute (AAI) at the University of Technology, Sydney (UTS). ICME 2012 features a new plenary session - Time Machine! The session consists of a series of expert presentations that re-introduce ideas published "before their time" and, as a result, their impact has not yet been fully realized. ICME 2012 also has outstanding lectures including keynote lectures and research overviews. ICME 2012 will offer several paper prizes, including Best Paper Award, Best Student Paper Award, and Best Demo Award. © 2012 IEEE.

Zhang, J, Schonfeld, D & Feng, DD 1970, 'Message from the ICME 2012 General Chairs', 2012 IEEE International Conference on Multimedia and Expo, 2012 IEEE International Conference on Multimedia and Expo (ICME), IEEE, pp. xix-xx.
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Zheng, C, Dutkiewicz, E, Ren Ping Liu, Vesilo, R & Zhou, Z 1970, 'Efficient network coding transmission in 2-hop multi-channel cognitive radio networks', 2012 International Symposium on Communications and Information Technologies (ISCIT), 2012 International Symposium on Communications and Information Technologies (ISCIT), IEEE, Gold Coast, QLD, Australia, pp. 574-579.
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In cognitive radio networks (CRNs), there is no guarantee on the availability of spectrum for the opportunistic communications between cognitive radio (CR) users. Transmission design plays a key role in leveraging the benefits of CRNs. In this paper, we propose an efficient batch transmission scheme for the data transmission in multi-channel CRNs with practical lossy channels. The proposed scheme exploits the dynamic spectrum opportunities by combining opportunistic routing strategy with network coding based multi-channel transmission. We derive network performance measures of the scheme in terms of batch delay, which provide better insights into the data transmission capability than packet based link delay analysis. Our analyses, validated by simulations, show that the proposed scheme significantly outperforms others, reducing batch delay by up to 60%. © 2012 IEEE.

Zhu, H & Chu, Q-X 1970, 'Ultra-wideband (UWB) bandpass filter with sharp selectivity and wide upper stopband', 2012 IEEE International Conference on Ultra-Wideband, 2012 IEEE International Conference on Ultra-Wideband (ICUWB2012), IEEE, pp. 103-105.
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A compact quadruple-mode ultra-wideband (UWB) bandpass filter with sharp selectivity and extremely wide upper stopband is proposed in this paper, using a multi-stage stepped-impedance resonator, two open-circuited ends and a pair of high-low impedance stubs. The characteristics of the proposed multimode resonator are analyzed by simulation, demonstrating that the first four resonant modes can be appropriately located in the desired passband and other resonant modes in the upper stopband can be suppressed. To improve the skirt selectivity and out-of-band performance, two identical high-low impedance stubs are introduced into the design, without changing any resonant characteristic of the filter. Finally, the improved filter is fabricated and measured, and simulated and measured results are in good agreement to show that the proposed filter has a sharp selectivity with a 21.5 dB rejection stopband extended to over 30 GHz. © 2012 IEEE.

Zhu, H, Chu, QX & Tian, XK 1970, 'A UWB bandpass filter using slotline ring resonator with a notched band', 2012 International Conference on Microwave and Millimeter Wave Technology (ICMMT), 2012 International Conference on Microwave and Millimeter Wave Technology (ICMMT), IEEE, pp. 1-4.
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A quadruple-mode UWB bandpass filter is presented. The proposed filter is comprised of a slotline ring resonator, which forms an ultra-wide passband with four resonant modes. Two pairs of defected ground patches are added to improve the desired passband. To achieve a wide upper stopband, a pair of defected ground dumbbell units is introduced. Moreover, a notch band is added around 5.5GHz using a U-shaped slotline to avoid wireless local-area network (WLAN) signals. Finally, a filter is fabricated and tested. Simulated and measured results are in good agreement to exhibit that the proposed UWB BPF has a passband from 3.1GHz to 10.9GHz with a notched band in 5.5GHz, and a wide upper stopband with attenuation level of -12.8 dB up to over 30GHz. © 2012 IEEE.

Barua, B, Abolhasan, M, Franklin, D & Safaei, F 2012, 'Outage Probability Analysis of Dual Hop Relay Networks in Presence of Interference'.
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Cooperative relaying improves the performance of wireless networks by forminga network of multiple independent virtual sources transmitting the sameinformation as the source node. However, interference induced in the networkreduces the performance of cooperative communications. In this work thestatistical properties, the cumulative distribution function (CDF) and theprobability density function (PDF) for a basic dual hop cooperative relaynetwork with an arbitrary number of interferers over Rayleigh fading channelsare derived. Two system models are considered: in the first system model, theinterferers are only at the relay node; and in the second system model,interferers are both at the relay and the destination. This work is furtherextended to Nakagami-m faded interfering channels. Simulation results arepresented on outage probability performance to verify the theoretical analysis.

Duffield, NG, Arya, V & Veitch, DN 2012, 'Multicast-based inference of temporal loss characteristics in packet data networks', Google Patents.

Gorst-Rasmussen, A, Veitch, D & Gefferth, A 2012, 'Why FARIMA models are brittle'.

Nguyen, D & Krunz, M 2012, 'Battery Lifetime Estimator (delivered to Raytheon Missile Systems, US)'.
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Modeling and Prediction Battery Lifetime of Wireless Sensor Nodes: Wireless sensors, powered by chemical battery, are often left unattended after deploying (e.g., in the jungle to monitor habitants, or in battlefields to track movement of enemy's troops). It is critical to model and predict the longevity of the network, that depends on lifetime of every sensor node. Lifetime of a sensor network depends on both the battery lifetime of individual nodes and how information is routed. Knowing how a battery discharges versus various traffic profiles allows us to configure the optimal duty cycle for each individual sensor (by leveraging the nonlinear discharge curve of chemical batteries). The optimal duty cycle of a sensor, in terms of network lifetime, depends on its position and how much data is relayed through it. In this project, we provide a software that can predict battery lifetime of a sensor under arbitrary discharge profiles (i.e., duty cycle) within 5% margin of DUALFOIL (University of California, Berkeley). The developed software is much faster (in minutes) than DUALFOIL (in days for a desktop with Intel Core 2 CPU 1.83GHz and 2G Ram) and allows one to optimize sensor mote's lifetime without requiring low-level simulations.