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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

Corner occupying theorem for the two-dimensional integral rectangle packing problem

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Science china(Information Sciences) 2012年第11期55卷 2466-2472页

作者： HUANG WenQi1,YE Tao1 & CHEN DuanBing2 1school of computer Science and Technology,Huazhong university of Science and Technology,Wuhan 430074,china 2Web Sciences Center,school of computer Science,university of Electronic Science and Technology of china,chengdu 611731,china 1. school of computer Science and Technology Huazhong University of Science and Technology Wuhan 430074 China2. Web Sciences Center School of Computer Science University of Electronic Science and Technology of China Chengdu 611731 China

This paper proves a corner occupying theorem for the two-dimensional integral rectangle packing problem,stating that if it is possible to orthogonally place n arbitrarily given integral rectangles into an integral rectangular container without overlapping,then we can achieve a feasible packing by successively placing a rectangle onto a bottom-left corner in the *** on this theorem,we might develop e?cient heuristic algorithms for solving the integral rectangle packing *** fact,as a vague conjecture,this theorem has been implicitly mentioned with different appearances by many people for a long time.

关键词： rectangle packing bottom-left corner occupying theorem NP hard

Presenting degenerate Ringel-Hall algebras of type B

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Science china mathematics 2012年第5期55卷 949-960页

作者： FAN LiJuan1 & ZHAO ZhongHua2,1Department of mathematics,Beijing Normal university,Beijing 100875,china 2Department of mathematics and computer Science,school of Science,Beijing university of Chemical Technology,Beijing 100029,china 1. Department of mathematics Beijing Normal University Beijing 100875 China2. Department of Mathematics and Computer Science School of Science Beijing University of Chemical Technology Beijing 100029 China

We give a presentation for the degenerate Ringel-Hall algebras of type B by studying the corresponding generic extension monoid *** an application,it is shown that the degenerate Ringel-Hall algebras of type B admit m... 详细信息

关键词： degenerate Ringel-Hall algebras generic extension monoid algebras Auslander-Reiten quivers Frobenius morphism

Semantic theory of finite lattice-valued propositional logic

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Science china(Information Sciences) 2010年第10期53卷 2022-2031页

作者： PAN XiaoDong 1,2 & XU Yang 2 1 school of Maths, Southwest Jiaotong university, chengdu 610031, china 2 Intelligent Control Development Center, Southwest Jiaotong university, chengdu 610031, china 1. school of Maths Southwest Jiaotong University Chengdu 610031 China2. Intelligent Control Development Center Southwest Jiaotong University Chengdu 610031 China

Based on the methodology of Pavelka’s fuzzy propositional logic, in this paper, by combining L-fuzzy set and classical two-value propositional logic theory, a kind of graded semantic theory in lattice-valued propositional logic based on finite lattice implication algebras is established. The notions of L-tautology and L-contradiction are introduced, and several theorems about the relations among different kinds of L-tautologies are given. From the viewpoint of uncertainty reasoning, the notion of satisfiability with certain level for a set of formulas is also defined. On this basis, the semantic consequence operation concerning a set of formulas is proposed, and the properties of semantic consequence operation and the consistency of fuzzy information are discussed.

关键词： lattice-valued propositional logic semantic theory L-tautology consistency lattice implication algebra

Formation control for networked spacecraft in deep space:with or without communication delays and with switching topology

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Science china(Information Sciences) 2011年第3期54卷 469-481页

作者： WANG Nan 1,2, ZHANG TianWu 2 & XU JieQiong 1 1 school of Aeronautic Science and engineering, Beijing university of Aeronautics and Astronautics, Beijing 100191, china 2 Department of computer Science and engineering, Henan Institute of engineering, Zhengzhou 451191, china 1. school of Aeronautic Science and engineering Beijing University of Aeronautics and Astronautics Beijing 100191 China2. Department of Computer Science and Engineering Henan Institute of Engineering Zhengzhou 451191 China

In this paper, several formation controllers are developed with constant and variable connected communication topology for six-degree-of-freedom (6-DOF) networked spacecraft flying in deep space with constant and time-varying communication delays considered. In the control algorithm, any explicit leader does not exist in the formation team and it is required that each spacecraft communicate only with its neighbors and therefore the required communication loads of the whole formation is greatly reduced. The proposed control strategies allow that each spacecraft can track its desired position and attitude and simultaneously the whole group moves to the desired formation and obtain its desired relative attitudes with its neighbors. Simulation results demonstrate the effectiveness of the proposed controllers.

关键词： deep space graph theory formation control communication topology delays

Distributed GIS oriented generalized image pyramid and its practice

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Science china(Technological Sciences) 2010年第S1期53卷 99-104页

作者： XIA YuBin,PANG PeiYu & WENG JingNong school of computer Science and engineering,Beihang university,Beijing 100191,china 1. school of computer Science and engineering Beihang University Beijing 100191 China

Gaussian pyramid framework (GPF) and Laplacian pyramid framework (LPF) are the two main frameworks used for transmission and structure of spatial image and geometric *** is the main approach for progressive transmission of spatial image *** paper discusses the issues in structure,transmission and storage efficiency of spatial data in the current spatially distributed visualization *** in the paper a novel approach is introduced to structure and store spatial data based on the *** new approach builds (spatial) index for transformed frequency data within different ranges based on splitting high-frequency and low-frequency data by biorthogonal *** approach decreases the storage consumption and network data traffic for transmission while enables the progressive transmission of spatial image.

关键词： redundancy spatial index progressive transmission generalized pyramid structure Laplacian pyramid framework

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An index-split Bloom filter for deep packet inspection

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Science china(Information Sciences) 2011年第1期54卷 23-37页

作者： HUANG Kun1 & ZHANG DaFang1,2 1school of computer and Communication,Hunan university,Changsha 410082,china 2 school of Software,Hunan university,Changsha 410082,china 1. school of computer and Communication Hunan University Changsha 410082 China2. School of Software Hunan University Changsha 410082 China

Deep packet inspection(DPI)scans both packet headers and payloads to search for predefined *** link rates and traffc volumes of Internet are constantly growing,DPI is facing the high performance challenge of how to achieve line-speed packet processing with limited embedded *** recent trie bitmap content analyzer(TriBiCa)suffers from high update overhead and many false positive memory accesses,while the shared-node fast hash table(SFHT)suffers from high update overhead and large memory *** paper presents an index-split Bloom filter(ISBF)to overcome these *** a set of off-chip items,an index of each item is split apart into several groups of constant bits,and each group of bits uses an array of on-chip parallel counting Bloom filters(CBFs)to represent the overall off-chip *** an item is queried,several groups of on-chip parallel CBFs constitute an index of an off-chip item candidate for a ***, we propose a lazy deletion algorithm and vacant insertion algorithm to reduce the update overhead of ISBF, where an on-chip deletion bitmap is used to update on-chip parallel CBFs,not adjusting other related off-chip *** ISBF is a time/space-effcient data structure,which not only achieves O(1)average memory accesses of insertion,deletion,and query,but also reduces the memory *** results demonstrate that compared with the TriBiCa and SFHT,the ISBF significantly reduces the off-chip memory accesses and processing time of primitive operations,as well as both the on-chip and off-chip memory sizes.

关键词： network security packet processing deep packet inspection hash table Bloom filter

Some geometric properties of successive difference substitutions

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Science china(Information Sciences) 2011年第4期54卷 778-786页

作者： HOU XiaoRong 1,XU Song 1,2 & SHAO JunWei 1 1 school of Automation engineering,university of Electronic Science and Technology of china,chengdu 611731,china 2 Faculty of Science,Ningbo university,Ningbo 315211,china 1. school of Automation engineering University of Electronic Science and Technology of China Chengdu 611731 China2. Faculty of Science Ningbo University Ningbo 315211 China

This paper provides a new,geometric perspective to study successive difference substitutions,and proves that the sequence of the successive difference substitution sets is not *** interesting result that a given k-dimensional rational hyperplane can be transformed to a k-dimensional coordinate hyperplane of new variables by finite steps of successive difference substitutions is ***,a sufficient condition for the sequence of the successive difference substitution sets of a form being not terminating is *** is,a class of polynomials which cannot be proved to be positive semi-definite by the successive difference substitution method are obtained.

关键词： successive difference substitutions nonnegativity decision of forms Barycentric subdivision

Experimental study of CT test on the failure of acrylate spray-applied waterproof layer in the groundwater environment

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Science china(Technological Sciences) 2010年第2期53卷 512-518页

作者： YANG QiXin, XU Peng & ZHENG ShangFeng 1 school of Civil engineering, Southwest Jiaotong university, chengdu 610031, china 1. school of Civil engineering Southwest Jiaotong University Chengdu 610031 China

In this study the computerized tomography (CT) was first used to quantitatively analyze the failure of acrylate spray-applied waterproof membrane in the groundwater environment. The results of the CT tests show that it is feasible to use the CT to quantitatively analyze the failure of the waterproof membrane and the CT method has the advantages of speediness and accuracy that can eliminate the fussy operation process in routine tests. The main conclusions summarized from the study are as follows. First, there are two combined-indexes that can be used to decide the failure of the spray-on waterproof layer: one is that the reduced percentage of the CT number of the spray-on waterproof layer is less than 40.0% and the other is that the variance of the CT number decreases first and then increases. Second, the applicability for the spray-on waterproof layer in the groundwater environment is the SO 24-concentration ≤ 1%, the Cl-concentration ≤ 7.5% and the pH value ≤ 12.0 of the groundwater, respectively.

关键词： spray-on waterproof layer scan CT number failure groundwater environment

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