Abolhasan, M, Wysocki, T & Dutkeiwicz, E 2001, 'A review of current on-demand routing protocols', NETWORKING - ICN 2001, PART II, PROCEEDINGS, vol. 2094, pp. 186-195.
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Mobile ad hoc networks are data networks entirely made up of enduser communication terminals (known as nodes). Each node in the network can act as an information sink (i.e. a receiver), a source and a router. All nodes have a transmission range, which is limited by their transmission power, attenuation and interference. Mobile ad hoc networks have a number of disadvantages over wired networks. These include limited bandwidth in the wireless medium, limited power supply and mobility. The traditional routing algorithms such as DBF will not work in such networks due to lack of scalability and ability to cope with highly mobile networks. Recently, a number of routing protocols have been designed to overcome these issues. These protocols can be classified into three different categories: global, on-demand and hybrid routing. In this paper, we provide a performance comparison for on-demand routing protocols, which is based on a number of different parameters. This paper also considers which protocol characteristics will produce better performance levels in these networks, and what improvements can be made to further increase the efficiency of some of these routing protocols.
Blunden, B & Indraratna, B 2001, 'Pyrite Oxidation Model for Assessing Ground-Water Management Strategies in Acid Sulfate Soils', Journal of Geotechnical and Geoenvironmental Engineering, vol. 127, no. 2, pp. 146-157.
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Indraratna, B & Ranjith, PG 2001, 'Laboratory Measurement of Two-Phase Flow Parameters in Rock Joints Based on High Pressure Triaxial Testing', Journal of Geotechnical and Geoenvironmental Engineering, vol. 127, no. 6, pp. 530-542.
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Indraratna, B, Aziz, NI & Dey, A 2001, 'Behaviour of joints containing clay infill under constant normal stiffness, with and without bolting', Proceedings of the Institution of Civil Engineers - Geotechnical Engineering, vol. 149, no. 4, pp. 259-267.
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The shear behaviour of bolted and non-bolted joints containing infill material was studied under the constant normal stiffness condition. More than 40 sawtooth-shaped samples having an asperity angle of 18·5° were tested. The shear behaviour of bolted and non-bolted joints containing infill material, up to 7·5 mm in thickness, was studied under various initial normal stress levels between 0·13 and 3·25 MPa, at a constant strain rate of 0·5 mm/min and a constant stiffness of 8·5 kN/mm. Significant reduction in shear strength was observed when the joint contained a layer of clay infill of 1·5 mm. Bolting contributed to increasing the strength and stiffness of the joint composite, except at large normal stress levels and at high infill thickness. The dilation and overall friction angle for bolted and non-bolted joints were also compared along with stress profiles. At high infill thickness, the shear behaviour under both constant normal load (CNL) and constant normal stiffness (CNS) conditions was found to be similar for both bolted and non-bolted joints, while at low infill thickness the CNL strength envelope plotted significantly above the CNS envelope.
Indraratna, B, Tularam, GA & Blunden, B 2001, 'Reducing the impact of acid sulphate soils at a site in Shoalhaven Floodplain of New South Wales, Australia', Quarterly Journal of Engineering Geology and Hydrogeology, vol. 34, no. 4, pp. 333-346.
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Oxidation of sulphide minerals in acid sulphate soils has acidified a substantial part of the low-lying coastal land in Australia. Such sulphides, including pyrite (FeS 2 ) formed thousands of years ago during saline inundation of soils rich in iron. They do not pose a serious concern when submerged by the water table, because this prevents atmospheric oxygen reacting with the pyritic layer. However, flood protection of low-lying coastal land through the installation of deep surface drains has caused a general lowering of the water table elevation, that in turn has exposed the pyritic layers to atmospheric oxygen. High rainfall following droughts causes acid pollution of the surrounding flood mitigation drains, creeks and river systems. Large ground areas are affected by the transport of acid constituents during seepage. One way of controlling new acid production is through the installation of weirs in the flood mitigation drains in order to raise the water table elevation. In this paper, the acid pollution in New South Wales is reviewed, and the effect of groundwater elevation is examined. Relationship between acid production and groundwater table is examined. Mathematical models are developed to simulate acid production and transport, and two groundwater management regimes are examined. Weir based control of the groundwater table is shown to be successful in controlling acid production.
Ji, JC 2001, 'Local bifurcation control of a forced single-degree-of-freedom nonlinear system: Saddle-node bifurcation', NONLINEAR DYNAMICS, vol. 25, no. 4, pp. 369-382.
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It is well known that saddle-node bifurcations can occur in the steady-state response of a forced single-degree-of-freedom (SDOF) nonlinear system in the cases of primary and superharmonic resonances. This discontinuous or catastrophic bifurcation can lead to jump and hysteresis phenomena, where at a certain interval of the control parameter, two stable attractors exist with an unstable one in between. A feedback control law is designed to control the saddle-node bifurcations taking place in the resonance response, thus removing or delaying the occurrence of jump and hysteresis phenomena. The structure of candidate feedback control law is determined by analyzing the eigenvalues of the modulation equations. It is shown that three types of feedback - linear, nonlinear, and a combination of linear and nonlinear - are adequate for the bifurcation control. Finally, numerical simulations are performed to verify the effectiveness of the proposed feedback control.
Ji, JC & Hansen, CH 2001, 'Non-linear oscillations of a rotor in active magnetic bearings', JOURNAL OF SOUND AND VIBRATION, vol. 240, no. 4, pp. 599-612.
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The non-linear response of a rotor supported by active magnetic bearings is investigated, and both primary and internal resonances are considered. The method of multiple scales is used to obtain four first order ordinary differential equations that describe the modulation of the amplitudes and phases of vibrations in the horizontal and vertical directions. The steady state response and the stability of the solutions are determined numerically from the reduced system. It is shown that the steady state solutions lose their stability by either saddle-node bifurcation or Hopf bifurcation. In the regime of multiple coexisting solutions, two stable solutions are found. The effect of imbalance eccentricity, as well as the effect of the proportional and derivative gains of the controller on the non-linear response of the system, are studied. Finally, numerical simulations are performed to verify the analytical predictions.
Locke, M, Indraratna, B & Adikari, G 2001, 'Time-Dependent Particle Transport through Granular Filters', Journal of Geotechnical and Geoenvironmental Engineering, vol. 127, no. 6, pp. 521-529.
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Sheng, D & Sloan, SW 2001, 'Erratum to the ‘Load stepping schemes for critical state models’ International Journal for Numerical Methods in Engineering 2001; 50:67–93', International Journal for Numerical Methods in Engineering, vol. 50, no. 10, pp. 2441-2441.
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AbstractThe original article to which this Erratum refers was published in Interntational Journal for Numerical Methods in Engineering 2001; 50:67–93.
Sheng, D & Sloan, SW 2001, 'Load stepping schemes for critical state models', International Journal for Numerical Methods in Engineering, vol. 50, no. 1, pp. 67-93.
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Sheng, D & Sloan, SW 2001, 'Load stepping schemes for critical state models', International Journal for Numerical Methods in Engineering, vol. 50, no. 1, pp. 67-93.
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This paper investigates the performance of various load-stepping schemes for finite element analysis with critical state soil models. The accuracy of simple incremental schemes is found to be strongly influenced by the load increment size, the type of flow rule, and the overconsolidation ratio. Similarly, these factors are shown to have a pronounced effect on the efficiency and stability of some classical iterative schemes. Unless they are performed with small load steps, critical state analyses with fixed increment sizes frequently exhibit non-convergent behaviour or lead to inaccurate solutions. The automatic incrementation schemes developed by Abbo and Sloan (International Journal for Numerical Methods in Engineering 1996; 39: 1737-1759; Proceedings of 5th International Conference, Owen DRJ, Onate E, Hinton E. International Center for Numerical Methods in Engineering, Barcelona, 1997; 1:325-333), which are based on standard methods for integrating systems of ordinary differential equations, are shown to be efficient, accurate and robust solution techniques for a wide variety of critical state problems. © 2001 John Wiley & Sons, Ltd.
Sloan, SW, Abbo, AJ & Sheng, D 2001, 'Refined explicit integration of elastoplastic models with automatic error control', Engineering Computations, vol. 18, no. 1/2, pp. 121-194.
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Yang Wang, Yi-Sheng Zhu, Thakor, NV & Yu-Hong Xu 2001, 'A short-time multifractal approach for arrhythmia detection based on fuzzy neural network', IEEE Transactions on Biomedical Engineering, vol. 48, no. 9, pp. 989-995.
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Blumenstein, M & Verma, B 1970, 'Analysis of segmentation performance on the CEDAR benchmark database', Proceedings of Sixth International Conference on Document Analysis and Recognition, Sixth International Conference on Document Analysis and Recognition, IEEE Comput. Soc, pp. 1142-1146.
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The purpose of this paper is to analyse the performance of our improved segmentation algorithm tested on the CEDAR benchmark database. Segmentation is achieved through the extraction of a wide range of information adjacent to or surrounding suspicious segmentation points. Initially, a heuristic technique is employed to search for structural features and to over-segment each word. For each segmentation point that is located, the left character (preceding the segmentation point), and centre character (centred on the segmentation point) are extracted along with other features from the segmentation area. The aforementioned features are presented to trained character and segmentation point validation neural networks to evaluate a number of confidence values. Finally, the confidence values are fused to obtain the final segmentation decision. Based on a detailed analysis, it was observed that the left and centre character networks increased the accuracy of the segmentation algorithm.
Ha, QP, Li, J, Hong, G & Samali, B 1970, 'Active structural control using dymanic output feedback sliding mode', Proceedings of the Australian Conference on Robotics and Automation ACRA'01, Australasian Conference on Robotics and Automation, Australian Robotics & Automation Association, Sydney, pp. 20-25.
Huang, W, Sheng, D, Yu, H-S & Sloan, SW 1970, 'Finite Element Simulation of Cone Penetration with Finite-Sliding Contact Interface', COMPUTATIONAL MECHANICS, VOLS 1 AND 2, PROCEEDINGS, 1st Asian-Pacific Congress on Computational Mechanics, Elsevier, SYDNEY, AUSTRALIA, pp. 351-356.
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Indraratna, BN, Ranjith, PG, Price, JR & Gale, W 1970, 'A preliminary study of the relationship between two-phase flow (airwater) characteristics and fracture roughness', DC Rocks 2001 - 38th U.S. Symposium on Rock Mechanics (USRMS), pp. 191-196.
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The study of hydromechanics has identified that surface roughness has an impact on the flow characteristics of single and two-phase fluids. Technical developments in the field of two-phase flow are of great importance for improving the understanding of underground inundation and gas outbursts, in order to reduce the risks to personnel. The paper describes recent advances in the understanding of two-phase (air-water) stratified flow. A new constitutive model is presented, based upon an extension of Darcy's Law and using the concept of relative permeability. The proposed model is verified by experimental results using 'state of the art' Two Phase High Pressure Triaxial Apparatus (TPHPTA). This study presents the results of laboratory testing that will enable the development of a relationship between roughness (Joint Roughness Coefficient, JRC) and the flow rate for steady state conditions.
Sheng, D, Lewis, T & Smith, DW 1970, 'Effects of Equilibria and Kinetics on Contaminant Transport', COMPUTATIONAL MECHANICS, VOLS 1 AND 2, PROCEEDINGS, 1st Asian-Pacific Congress on Computational Mechanics, Elsevier, SYDNEY, AUSTRALIA, pp. 789-794.
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Sheng, DC, Smith, DW & Sloan, SW 1970, 'Alternative finite element formulation for unsaturated soils', COMPUTATIONAL MECHANICS, VOLS 1 AND 2, PROCEEDINGS, 1st Asian-Pacific Congress on Computational Mechanics, ELSEVIER SCIENCE BV, SYDNEY, AUSTRALIA, pp. 1389-1394.
