Cao, YZ & Ying, MS 2006, 'Observability and decentralized control of fuzzy discrete-event systems', IEEE TRANSACTIONS ON FUZZY SYSTEMS, vol. 14, no. 2, pp. 202-216.
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Fuzzy discrete-event systems as a generalization of (crisp) discrete-event systems have been introduced in order that it is possible to effectively represent uncertainty, imprecision, and vagueness arising from the dynamic of systems. A fuzzy discrete-event system has been modeled by a fuzzy automaton; its behavior is described in terms of the fuzzy language generated by the automaton. In this paper, we are concerned with the supervisory control problem for fuzzy discrete-event systems with partial observation. Observability, normality, and co-observability of crisp languages are extended to fuzzy languages. It is shown that the observability, together with controllability, of the desired fuzzy language is a necessary and sufficient condition for the existence of a partially observable fuzzy supervisor. When a decentralized solution is desired, it is proved that there exist local fuzzy supervisors if and only if the fuzzy language to be synthesized is controllable and co-observable. Moreover, the infimal controllable and observable fuzzy superlanguage, and the supremal controllable and normal fuzzy sublanguage are also discussed. Simple examples are provided to illustrate the theoretical development. © 2006 IEEE.
Cao, YZ & Ying, MS 2006, 'Similarity-based supervisory control of discrete-event systems', IEEE TRANSACTIONS ON AUTOMATIC CONTROL, vol. 51, no. 2, pp. 325-330.
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Due to the appearance of uncontrollable events in discrete-event systems, one may wish to replace the behavior leading to the uncontrollability of pre-specified language by some quite similar one. To capture this similarity, we introduce metric to tradit
Cole, JH, Devitt, SJ & Hollenberg, LCL 2006, 'Precision characterization of two-qubit Hamiltonians via entanglement mapping', Journal of Physics A: Mathematical and General, vol. 39, no. 47, pp. 14649-14658.
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Duan, R, Feng, Y & Ying, M 2006, 'Partial recovery of quantum entanglement', IEEE TRANSACTIONS ON INFORMATION THEORY, vol. 52, no. 7, pp. 3080-3104.
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Suppose Alice and Bob try to transform an entangled state shared between them into another one by local operations and classical communications. Then in general a certain amount of entanglement contained in the initial state will decrease in the process of transformation. However, an interesting phenomenon called partial entanglement recovery shows that it is possible to recover some amount of entanglement by adding another entangled state and transforming the two entangled states collectively. In this paper, we are mainly concerned with the feasibility of partial entanglement recovery. The basic problem we address is whether a given state is useful in recovering entanglement lost in a specified transformation. In the case where the source and target states of the original transformation satisfy the strict majorization relation, a necessary and sufficient condition for partial entanglement recovery is obtained. For the general case we give two sufficient conditions. We also give an efficient algorithm for the feasibility of partial entanglement recovery in polynomial time. As applications, we establish some interesting connections between partial entanglement recovery and the generation of maximally entangled states, quantum catalysis, mutual catalysis, and multiple-copy entanglement transformation. © 2006 IEEE.
Duan, R-Y, Ji, Z-F, Feng, Y & Ying, M-S 2006, 'Some issues in quantum information theory', JOURNAL OF COMPUTER SCIENCE AND TECHNOLOGY, vol. 21, no. 5, pp. 776-789.
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Quantum information theory is a new interdisciplinary research field related to quantum mechanics, computer science, information theory, and applied mathematics. It provides completely new paradigms to do information processing tasks by employing the pri
Feng, Y, Duan, R & Ji, Z 2006, 'Optimal dense coding with arbitrary pure entangled states', Physical Review A - Atomic, Molecular, and Optical Physics, vol. 74, no. 1, pp. 1-5.
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We examine dense coding with an arbitrary pure entangled state sharing between the sender and the receiver. Upper bounds on the average success probability in approximate dense coding and on the probability of conclusive results in unambiguous dense coding are derived. We also construct the optimal protocol which saturates the upper bound in each case. © 2006 The American Physical Society.
Feng, Y, Duan, R & Ji, Z 2006, 'Optimal dense coding with arbitrary pure entangled states', Phys. Rev. A, vol. 74, no. 1, p. 012310.
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We examine dense coding with an arbitrary pure entangled state sharingbetween the sender and the receiver. Upper bounds on the average successprobability in approximate dense coding and on the probability of conclusiveresults in unambiguous dense coding are derived. We also construct the optimalprotocol which saturates the upper bound in each case.
Feng, Y, Duan, R & Ying, M 2006, 'Relation between catalyst-assisted transformation and multiple-copy transformation for bipartite pure states', PHYSICAL REVIEW A, vol. 74, no. 4, pp. 1-7.
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We show that in some cases, catalyst-assisted entanglement transformation cannot be implemented by multiple-copy transformation for pure states. This fact, together with the result we obtained in R. Y. Duan, Y. Feng, X. Li, and M. S. Ying, Phys. Rev. A 71, 042319 (2005), namely that the latter can be completely implemented by the former, indicates that catalyst-assisted transformation is strictly more powerful than multiple-copy transformation. For the purely probabilistic setting we find, however, these two kinds of transformations are geometrically equivalent in the sense that the sets of pure states that can be converted into a given pure state with maximal probabilities not less than a given value have the same closure, regardless of whether catalyst-assisted transformation or multiple-copy transformation is used. © 2006 The American Physical Society.
Feng, Y, Duan, R, Ji, Z & Ying, M 2006, 'Probabilistic bisimilarities between quantum processes', Information and Computation, vol. 2007, p. 205.
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Modeling and reasoning about concurrent quantum systems is very importantboth for distributed quantum computing and for quantum protocol verification.As a consequence, a general framework describing formally the communication andconcurrency in complex quantum systems is necessary. For this purpose, wepropose a model qCCS which is a natural quantum extension of classicalvalue-passing CCS with the input and output of quantum states, and unitarytransformations and measurements on quantum systems. The operational semanticsof qCCS is given based on probabilistic labeled transition system. Thissemantics has many different features compared with the proposals in literaturein order to describe input and output of quantum systems which are possiblycorrelated with other components. Based on this operational semantics, weintroduce the notions of strong probabilistic bisimilarity and weakprobabilistic bisimilarity between quantum processes and discuss someproperties of them, such as congruence under various combinators.
Greentree, AD, Devitt, SJ & Hollenberg, LCL 2006, 'Quantum-information transport to multiple receivers', Physical Review A, vol. 73, no. 3.
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Ji, ZF, Feng, Y, Duan, RY & Ying, MS 2006, 'Boundary effect of deterministic dense coding', PHYSICAL REVIEW A, vol. 73, no. 3, pp. 1-3.
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We present a rigorous proof of an interesting boundary effect of deterministic dense coding first observed by S. Mozes, J. Oppenheim, and B. Reznik [Phys. Rev. A 71, 012311 (2005)]. Namely, it is shown that d2 -1 cannot be the maximal alphabet size of any isometric deterministic dense coding schemes utilizing d -level partial entanglement. © 2006 The American Physical Society.
Ji, ZF, Feng, Y, Duan, RY & Ying, MS 2006, 'Identification and distance measures of measurement apparatus', PHYSICAL REVIEW LETTERS, vol. 96, no. 20, pp. 1-4.
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We propose simple schemes that can perfectly identify projective measurement apparatuses secretly chosen from a finite set. Entanglement is used in these schemes both to make possible the perfect identification and to improve the efficiency significantly. Based on these results, a brief discussion on the problem of how to appropriately define distance measures of measurements is also provided. © 2006 The American Physical Society.
Li, F, Vipulanandan, C, Zhou, YX & Salama, K 2006, 'Nanoscale Y2BaCuO5particles for producing melt-textured YBCO large grains', Superconductor Science and Technology, vol. 19, no. 6, pp. 589-595.
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Formalization of topological relations between spatial objects is an important aspect of spatial representation and reasoning. The well-known 9-Intersection Method (9IM) was previously used to characterize topological relations between simple regions, i.e. regions with connected boundary and exterior. This simplified abstraction of spatial objects as simple regions cannot model the variety and complexity of spatial objects. For example, countries like Italy may contain islands and holes. It is necessary that existing formalisms, 9IM in particular, cover this variety and complexity. This paper generalizes 9IM to cope with general regions, where a (general) region is a non-empty proper regular closed subset of the Euclidean plane. We give a complete classification of topological relations between plane regions. For each possible relation we either show that it violates some topological constraints and hence is non-realizable or find two plane regions it relates. Altogether 43 (out of 512) relations are identified as realizable. Among these, five can be realized only between exotic (plane) regions, where a region is exotic if there is another region that has the same boundary but is not its complement. For all the remaining 38 relations, we construct configurations by using sums, differences and complements of discs. © 2006 Taylor & Francis Group, LLC.
Li, S 2006, 'A complete classification of topological relations using the 9‐intersection method', International Journal of Geographical Information Science, vol. 20, no. 6, pp. 589-610.
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Formalization of topological relations between spatial objects is an important aspect of spatial representation and reasoning. The well-known 9-Intersection Method (9IM) was previously used to characterize topological relations between simple regions, i.e. regions with connected boundary and exterior. This simplified abstraction of spatial objects as simple regions cannot model the variety and complexity of spatial objects. For example, countries like Italy may contain islands and holes. It is necessary that existing formalisms, 9IM in particular, cover this variety and complexity. This paper generalizes 9IM to cope with general regions, where a (general) region is a non-empty proper regular closed subset of the Euclidean plane. We give a complete classification of topological relations between plane regions. For each possible relation we either show that it violates some topological constraints and hence is non-realizable or find two plane regions it relates. Altogether 43 (out of 512) relations are identified as realizable. Among these, five can be realized only between exotic (plane) regions, where a region is exotic if there is another region that has the same boundary but is not its complement. For all the remaining 38 relations, we construct configurations by using sums, differences and complements of discs.
Li, S 2006, 'On Topological Consistency and Realization', Constraints, vol. 11, no. 1, pp. 31-51.
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Topological relations are important in various tasks of spatial reasoning, scene description and object recognition. The RCC8 spatial constraint language developed by Randell, Cui and Cohn (1992) is widely recognized as of particular importance in both t
Li, S & Li, Y 2006, 'On the complemented disk algebra', The Journal of Logic and Algebraic Programming, vol. 66, no. 2, pp. 195-211.
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The importance of relational methods in temporal and spatial reasoning has been widely recognised in the last two decades. A quite large part of contemporary spatial reasoning is concerned with the research of relation algebras generated by the
Li, S & Wang, H 2006, 'RCC8 binary constraint network can be consistently extended', Artificial Intelligence, vol. 170, no. 1, pp. 1-18.
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The RCC8 constraint language developed by Randell et al. has been popularly adopted by the Qualitative Spatial Reasoning and GIS communities. The recent observation that RCC8 composition table describes only weak composition instead of composition raises questions about Renz and Nebel's maximality results about the computational complexity of reasoning with RCC8. This paper shows that any consistent RCC8 binary constraint network (RCC8 network for short) can be consistently extended. Given ?, an RCC8 network, and z, a fresh variable, suppose xTyset membership, variant? and T is contained in the weak composition of R and S. This means that we can add two new constraints xRz and zSy to ? without changing the consistency of the network. The result guarantees the applicability to RCC8 of one key technique, (Theorem 5) of [J. Renz, B. Nebel, On the complexity of qualitative spatial reasoning: A maximal tractable fragment of the Region Connection Calculus. Artificial Intelligence 108 (1999) 69123], which allows the transfer of tractability of a set of RCC8 relations to its closure under composition, intersection, and converse.
Oi, DKL, Devitt, SJ & Hollenberg, LCL 2006, 'Scalable Error Correction in Distributed Ion Trap Computers', Phys. Rev. A., vol. 74, no. 5, p. 052313.
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A major challenge for quantum computation in ion trap systems is scalableintegration of error correction and fault tolerance. We analyze a distributedarchitecture with rapid high fidelity local control within nodes and entangledlinks between nodes alleviating long-distance transport. We demonstratefault-tolerant operator measurements which are used for error correction andnon-local gates. This scheme is readily applied to linear ion traps whichcannot be scaled up beyond a few ions per individual trap but which have accessto a probabilistic entanglement mechanism. A proof-of-concept system ispresented which is within the reach of current experiment.
Wang, GM & Ying, MS 2006, 'Unambiguous discrimination among quantum operations', PHYSICAL REVIEW A, vol. 73, no. 4, pp. 1-5.
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We address the problem of unambiguous discrimination among a given set of quantum operations. The necessary and sufficient condition for them to be unambiguously distinguishable is derived in the cases of single use and multiple uses, respectively. For the latter case we explicitly construct the input states and corresponding measurements that accomplish the task. It is also found that the introduction of entanglement can improve the discrimination. © 2006 The American Physical Society.
Wei, Z & Ying, M 2006, 'A relation between fidelity and quantum adiabatic evolution', PHYSICS LETTERS A, vol. 356, no. 4-5, pp. 312-315.
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Recently, some quantum algorithms have been implemented by quantum adiabatic evolutions. In this Letter, we discuss the accurate relation between the running time and the distance of the initial state and the final state of a kind of quantum adiabatic ev
Wei, Z, Ji, Z & Ying, M 2006, 'Majorization in quantum adiabatic algorithms', PHYSICAL REVIEW A, vol. 74, no. 4, pp. 1-7.
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The majorization theory has been applied to analyze the mathematical structure of quantum algorithms. An empirical conclusion by numerical simulations obtained in the previous literature indicates that step-by-step majorization seems to appear universally in quantum adiabatic algorithms. In this paper, a rigorous analysis of the majorization arrow in a special class of quantum adiabatic algorithms is carried out. In particular, we prove that for any adiabatic algorithm of this class, step-by-step majorization of the ground state holds exactly. For the actual state, we show that step-by-step majorization holds approximately, and furthermore that the longer the running time of the algorithm, the better the approximation. © 2006 The American Physical Society.
Wei, ZH & Ying, MS 2006, 'A modified quantum adiabatic evolution for the Deutsch-Jozsa problem', PHYSICS LETTERS A, vol. 354, no. 4, pp. 271-273.
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Deutsch-Jozsa algorithm has been implemented via a quantum adiabatic evolution by S. Das et al. [S. Das, R. Kobes, G. Kunstatter, Phys. Rev. A 65 (2002) 062310]. This adiabatic algorithm gives rise to a quadratic speed up over classical algorithms. We sh
Xia, L & Li, S 2006, 'On minimal models of the Region Connection Calculus', Fundamenta Informaticae, vol. 69, no. 4, pp. 427-446.
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Region Connection Calculus (RCC) is one primary formalism of qualitative spatial reasoning. Standard RCC models are continuous ones where each region is infinitely divisible. This contrasts sharply with the predominant use of finite, discrete models in applications. In a recent paper, Li et al. (2004) initiate a study of countable models that can be constructed step by step from finite models. Of course, some basic problems are left unsolved, for example, how many non-isomorphic countable RCC models are there? This paper investigates these problems and obtains the following results: (i) the exotic RCC model described by Gotts (1996) is isomorphic to the minimal model given by Li and Ying (2004); (ii) there are continuum many non-isomorphic minimal RCC models, where a model is minimal if it can be isomorphically embedded in each RCC model.
Ying, MS 2006, 'Linguistic quantifiers modeled by Sugeno integrals', ARTIFICIAL INTELLIGENCE, vol. 170, no. 6-7, pp. 581-606.
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Since quantifiers have the ability of summarizing the properties of a class of objects without enumerating them, linguistic quantification is a very important topic in the field of high level knowledge representation and reasoning. This paper introduces
Zhang, C, Feng, YA & Ying, MS 2006, 'Unambiguous discrimination of mixed quantum states', PHYSICS LETTERS A, vol. 353, no. 4, pp. 300-306.
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The problem of unambiguous discrimination between mixed quantum states is addressed by isolating the part of each mixed state which has no contribution to discrimination and by employing the strategy of set discrimination of pure states. A necessary and sufficient condition of unambiguous mixed state discrimination is presented. An upper bound of the efficiency is also derived. © 2006 Elsevier B.V. All rights reserved.
Zhang, C, Ying, M & Qiao, B 2006, 'Universal programmable devices for unambiguous discrimination', PHYSICAL REVIEW A, vol. 74, no. 4, pp. 1-9.
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We discuss the problem of designing unambiguous programmable discriminators for any n unknown quantum states in an m -dimensional Hilbert space. The discriminator is a fixed measurement that has two kinds of input registers: the program registers and the data register. The quantum state in the data register is what users want to identify, which is confirmed to be among the n states in program registers. The task of the discriminator is to tell the users which state stored in the program registers is equivalent to that in the data register. First, we give a necessary and sufficient condition for judging an unambiguous programmable discriminator. Then, if m=n, we present an optimal unambiguous programmable discriminator for them, in the sense of maximizing the worst-case probability of success. Finally, we propose a universal unambiguous programmable discriminator for arbitrary n quantum states. © 2006 The American Physical Society.
Barreiro, JT, Peters, NA, Kwiat, PG, Langford, NK & White, AG 1970, 'Joint polarization and spatial-mode entanglement of photons', Optics InfoBase Conference Papers.
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Simultaneous multidimensional entanglement can improve quantum communi-cation protocols, measurements and fundamental studies. Using photons from parametric downconversion, we demonstrate a source of joint polarization and spatial-mode entangle-ment, and characterize the state by tomographic reconstruction. © 2005 Optical Society of America.
Barreiro, JT, Peters, NA, Langford, NK & Kwiat, PG 1970, 'Hyper-entanglement: Generation and applications', 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference, IEEE, pp. 1-2.
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Producing photons entangled independently in orbital angular-momentum, polarization, and energy-time, we realize a source of "hyper"- entanglement. Such a source enables new quantum communication capabilities. We propose and demonstrate remote tunable preparation of entangled states. © 2006 Optical Society of America.
Barreiro, JT, Peters, NA, Langford, NK & Kwiat, PG 1970, 'Hyper-entanglement: Generation and applications', Optics InfoBase Conference Papers.
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Producing photons entangled independently in orbital angular-momentum, polarization, and energy-time, we realize a source of 'hyper'-entanglement. Such a source enables new quantum communication capabilities. We propose and demonstrate remote tunable preparation of entangled states. © 2006 Optical Society of America.
Brun, T, Devetak, I & Hsieh, M 1970, 'Entanglement-assisted quantum error correction', The 6th Asian Conference on Quantum Information Science (AQIS06), BeiJing, China.
Fortnow, L, Lee, T & Vereshchagin, N 1970, 'Kolmogorov Complexity with Error', Springer Berlin Heidelberg, pp. 137-148.
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Hollenberg, LCL, Greentree, AD, Wellard, CJ, Fowler, AG, Devitt, SJ & Cole, JH 1970, 'Qubit Transport and Fault-tolerant Architectures in Silicon', 2006 INTERNATIONAL CONFERENCE ON NANOSCIENCE AND NANOTECHNOLOGY, VOLS 1 AND 2, International Conference on Nanoscience and Nanotechnology, IEEE, AUSTRALIA, Brisbane, pp. 655-+.
Hollenberg, LCL, Greentree, AD, Wellard, CJ, Fowler, AG, Devitt, SJ & Cole, JH 1970, 'Qubit Transport and Fault-tolerant Architectures in Silicon', 2006 International Conference on Nanoscience and Nanotechnology, 2006 International Conference on Nanoscience and Nanotechnology, IEEE, pp. 348-350.
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We review a new adiabatic scheme - coherent spin transport by adiabatic passage (CSTAP) - for physical qubit transport particularly suited to atomic and solid-state systems. Several applications immediately follow, including a 2D Si:P donor electron spin architecture for quantum computing, and protocols for generating entangled states across non-local qubits. © 2006 IEEE.
Laplante, S, Lee, T & Szegedy, M 1970, 'THE QUANTUM ADVERSARY METHOD AND CLASSICAL FORMULA SIZE LOWER BOUNDS', computational complexity, Springer Science and Business Media LLC, pp. 163-196.
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Li, S 1970, 'Combining Topological and Directional Information: First Results', Knowledge Science, Engineering And Management : Lecture Notes in Artificial Intelligence Vol 4092, International Conference on Knowledge Science, Engineering and Management, Springer Berlin Heidelberg, Guilin, China, pp. 252-264.
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Representing and reasoning about spatial information is important in artificial intelligence and geographical information science. Relations between spatial entities are the most important kind of spatial information. Most current formalisms of spatial relations focus on one single aspect of space. This contrasts sharply with real world applications, where several aspects are usually involved together. This paper proposes a qualitative calculus that combines a simple directional relation model with the well-known topological RCC5 model. We show by construction that the consistency of atomic networks can be decided in polynomial time.
Memis, OG, Kong, SC, Katsnelson, A, Tomamichel, MP & Mohseni, H 1970, 'A Novel Avalanche Free Single Photon Detector', 2006 Sixth IEEE Conference on Nanotechnology, 2006 Sixth IEEE Conference on Nanotechnology, IEEE, pp. 742-745.
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We have conceived a novel single photon detector for IR wavelengths above 1 μm. The detection mechanism is based on carrier focalization and nano-injection. Preliminary measured data from unpassivated devices show a very high internal gain and low dark current at 1.55 μm at room temperature © 2006 IEEE.
