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Basin filling algorithm for the circular packing problem with equilibrium behavioral constraints

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Science china(information Sciences) 2010年第5期53卷 885-895页

作者： LIU JingFa1& LI Gang2 1school of Computer and Software, nanjing university of information Science & Technology, nanjing 210044, china 2school of Mathematics and Physics, nanjing university of information Science & Technology, nanjing 210044, china 1. school of Computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

With the background of the satellite module layout design, the circular packing problem with equilibrium behavioral constraints is a layout optimization problem and NP-hard problem in math. For lack of a powerful optimization method, this problem is hard to solve. The energy landscape paving (ELP) method is a class of stochastic global optimization algorithms based on the Monte Carlo sampling. Based on the quasiphysical strategy and the penalty function method, the problem is converted into an unconstrained optimization problem. Here by combining the improved ELP method, the gradient method based on local search and the heuristic configuration update mechanism, a new global search algorithm, basin filling algorithm, is put forward. The numerical results show that the proposed algorithm is effective to solving the circular packing problem with equilibrium behavioral constraints, and is easy to be popularized to other layout optimization problems.

关键词： equilibrium behavioral constraints packing problem layout optimization

SOME RESULTS ON GENERALIZED DIFFERENCE SETS

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Journal of Systems Science & Complexity 2008年第1期21卷 76-84页

作者： Xiwang CAO school of Mathematical Science, nanjing university of Aeronautics and Astronautics, nanjing 210016, china State Key Lab. of information security, Beijing 100049, china. school of Mathematical Science Nanjing University of Aeronautics Astronautics Nanjing 210016 China State Key Lab. of information security Beijing 100049 China

Sequences with ideal correlation functions have important applications in communications such as CDMA, FDMA, etc. It has been shown that difference sets can be used to construct such sequences. The author extends Pott and Bradley＇s method to a much broader case by proposing the concept of generalized difference sets. Some necessary conditions for the existence of generalized difference sets are established by means of some Diophantine equations. The author also provides an algorithm to determine the existence of generalized difference sets in the cyclic group Zv. Some examples are presented to illustrate that our method works.

关键词： Correlation functions diophantine equations generalized difference sets.

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A new heuristic algorithm for the circular packing problem with equilibrium constraints

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Science china(information Sciences) 2011年第8期54卷 1572-1584页

作者： LIU JingFa 1,2,LI Gang 3 & GENG HuanTong 1 1 school of Computer and Software,nanjing university of information Science & Technology,nanjing 210044,china 2 Network information Center,nanjing university of information Science & Technology, nanjing 210044,china 3 school of Mathematics and Physics,nanjing university of information Science & Technology,nanjing 210044,china 1. school of Computer and Software Nanjing University of Information Science & Technology Nanjing 210044 China2. Network Information Center Nanjing University of Information Science & Technology Nanjing 210044 China3. School of Mathematics and Physics Nanjing University of Information Science & Technology Nanjing 210044 China

The circular packing problem with equilibrium constraints is an optimization problem about simplified satellite module layout design.A heuristic algorithm based on tabu search is put forward for solving this *** algorithm begins from a random initial configuration and applies the gradient method with an adaptive step length to search for the minimum energy *** jump out of the local minima and avoid the search doing repeated work,the algorithm adopts the strategy of tabu *** the process of tabu search,we improve the traditional neighboring solutions,tabu objects and the acceptance criteria of the current solution *** test two sets of benchmarks consisting of 11 representative instances from the current *** numerical results show that the proposed algorithm breaks the records in seven out of 11 instances,and obtains the optimal solutions for the other four instances.

关键词： equilibrium constraints packing problem heuristic algorithm tabu search layout optimization

MMSE relay precoding schemes based on quantization error compensation for multi-relay system

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Science china(information Sciences) 2010年第12期53卷 2548-2556页

作者： LI Ting 1,2 & YANG LuXi 2 1 College of Communication and information Engineering,nanjing university of Posts and Telecommunications,nanjing 210003,china 2 school of information Science and Engineering,Southeast university,nanjing 210096,china 1. College of Communication and information Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 China2. School of Information Science and Engineering Southeast University Nanjing 210096 China

In order to deal with the performance degradation resulting from the quantization error,this paper introduces the statistics of Grassmannian codebook's quantization error into relay precoding design for multirelay *** on the two-step MMSE optimization algorithm for relay precoding and receiver equalizing with full feedback under QoS requirements,we first propose a limited feedback two-step MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation,and then we propose a limited feedback joint MMSE optimization scheme for relay precoding and receiver equalizing with quantization error compensation subject to a global power constraint at the output of *** results show that the proposed joint MMSE optimization scheme with quantization error compensation has a much lower bit-error rate than the two-step MMSE optimization scheme with quantization error compensation and the joint MMSE optimization scheme without quantization error compensation.

关键词： multi-relay precoding limited feedback minimum mean square error

Comparing logic coverage criteria on test case prioritization

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Science china(information Sciences) 2012年第12期55卷 2826-2840页

作者： FANG ChunRong 1,2,CHEN ZhenYu 1,2 & XU BaoWen 1 1 State Key Laboratory for Novel Software Technology,nanjing university,nanjing 210093,china 2 Software Institute,nanjing university,nanjing 210093,china 1. State Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China2. Software Institute Nanjing University Nanjing 210093 China

Logic coverage criteria have been widely used in the testing of safety-critical *** the past few years,fault-based logic coverage criteria have been studied intensively both in theory and in ***,there is a lack of authentic evidence of the comparison of fault-based logic coverage criteria with other logic coverage criteria,such as branch coverage and modified condition/decision coverage(MC/DC).In this paper,we present a comprehensive empirical study that compares these logic coverage criteria on test case prioritization,which is currently a hot topic in software *** useful conclusions are drawn from our research:(1) Fine-grained coverage criteria are always more effective and efficient.(2) The effectiveness of fault-based logic coverage criteria is not significantly different from that of MC/DC in terms of statistics,but the former is more stable.(3) A random strategy is more effective than branch coverage if a certain number of test cases are redundant.

关键词： fault detection capability logic coverage fault-based testing test case prioritization

Restrictive mechanism of flow control among non-cooperative Internet users

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Science china(information Sciences) 2011年第1期54卷 12-22页

作者： TAO Jun1,2,ZHONG Xiao1,2 & LU YiFei1,2 1Key Laboratory of Computer Network and information Integration,Southeast university, Ministry of Education,nanjing 210096,china 2school of Computer Science and Engineering,Southeast university,nanjing 210096,china 1. Key Laboratory of Computer Network and information Integration Southeast University Ministry of Education Nanjing 210096 China2. School of Computer Science and Engineering Southeast University Nanjing 210096 China

The flow and congestion control methods based on one-shot game model with non-cooperative game theory can explain the non-cooperative behavior of Internet ***,the low effciency of equilibrium solutions affects their *** the behavior of flow and congestion control based on infinitely repeated game models is addressed;the repeated and infinitely repeated flow and congestion control game model is presented; the existence and optimization of the Nash equilibrium point are proved;the discount factor in repeated game is discussed;the punishment and threat strategy to users'misbehavior is studied in N-users infinitely flow control game;the punishment restrictive method of users'behavior is designed in infinitely and finitely games;finally,a flow control algorithm based on repeated game,FCAR,is provided based on the conclusions of repeated game *** results of experiment and simulation show that FCAR algorithm could regularize and restrict users' misbehavior *** algorithm can also make non-cooperative Internet users achieve cooperation in order to optimize the utility of the whole flow and congestion control system.

关键词： Nash equilibrium utility infinitely and finitely repeated game flow and congestion control

Exploiting remote learners in Internet environment with agents

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Science china(information Sciences) 2010年第1期53卷 64-76页

作者： LI Ming, WANG Wei & ZHOU ZhiHua national Key Laboratory for Novel Software Technology, nanjing university, nanjing 210093, china 1. national Key Laboratory for Novel Software Technology Nanjing University Nanjing 210093 China

Data in the Internet are scattered on different sites indeliberately, and accumulated and updated frequently but not synchronously. It is infeasible to collect all the data together to train a global learner for prediction; even exchanging learners trained on different sites is costly. In this paper, aggregative-learning is proposed. In this paradigm, every site maintains a local learner trained from its own data. Upon receiving a request for prediction, an aggregative-learner at a local site activates and sends out many mobile agents taking the request to potential remote learners. The prediction of the aggregative-learner is made by combining the local prediction and the responses brought back by the agents. Theoretical analysis and simulation experiments show the superiority of the proposed method.

关键词： machine learning data mining aggregative-learning mobile agent Internet environment

Performance analysis of variable-power adaptive modulation in space-time block coded MIMO diversity systems

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Science china(information Sciences) 2010年第10期53卷 2106-2115页

作者： YU XiangBin 1,2 & SHI HuiBin 1 1 College of information Science and Technology, nanjing university of Aeronautics and Astronautics, nanjing 210016, china 2 national Mobile Communications Research Laboratory, Southeast university, nanjing 210096, china 1. College of information Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China2. National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

In this paper, the performance analysis of multi-antenna MIMO systems with variable-power (VP) adaptive modulation and space-time coding is presented. The fading gain value is partitioned into a number of regions by which we decide the transmission power according to the region the fading gain falls in. The optimum fading gain region boundaries (switching thresholds) for maximizing spectrum efficiency (SE) under a target BER and average power constraint are derived. It is shown that the Lagrange multiplier in the constrained SE optimization will be unique if the existence condition for multi-antenna systems is satisfied, and is unique for single antenna systems. A practical iterative calculation method based on Steepest Descent Algorithm for finding the Lagrange multiplier is proposed. With the switching thresholds, the closed-form expressions of the SE and average BER, respectively for VP system and constant-power (CP) system are achieved. Simulation results for SE and average BER are in good agreement with the theory analysis. The results show that VP adaptive modulation with space-time coding provides better SE than the counterpart with CP under a target BER and average power constraint.

关键词： adaptive modulation variable power space-time block code constant power multiple input multiple output (MIMO)

Selection of unitary operations in quantum secret sharing without entanglement

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Science china(information Sciences) 2011年第9期54卷 1837-1842页

作者： XU Juan 1,CHEN HanWu 1,LIU WenJie 1,2 & LIU ZhiHao 1 1 school of Computer Science and Engineering,Southeast university,nanjing 210096,china 2 school of Computer and Software,nanjing university of information Science and Technology,nanjing 210044,china 1. school of Computer Science and Engineering Southeast University Nanjing 210096 China2. School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 China

We propose a substitute-Bell-state attack strategy for quantum secret sharing schemes without entanglement,as well as a definition of the minimum failure probability of such attack strategy.A quantitative analysis of security degrees corresponding to different unitary operations is also provided,when the secret sharing schemes without entanglement are stricken by substitute-Bell-state *** a result,the relation between the selection of unitary operations and the effect of substitute-Bell-state attack is shown,which can serve as an important guidance for the selection of unitary operations in designing and implementing quantum secret sharing schemes.

关键词： quantum secret sharing substitute-Bell-state attack unitary operation minimum failure probability