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An analytical model for SMAC protocol in multi-hop wireless sensor networks

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Science china(Information Sciences) 2010年第11期53卷 2323-2331页

作者： LUO Jun, JIANG LingGe& HE Chen department of Electronic Engineering, shanghai jiaotong university, {2. 2.02.0, china 1. department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240 China

Considering the active/sleep dynamics and the contention backoscheme of SMAC protocol in multi-hop wireless sensor networks (WSNs), we model each node as a finite single server queue with server shutdown, and model each node’s states as a two-dimensional continuous-time Markov chain. Based on the model, we derive the network performance in terms of average packet loss ratio, network throughput, average packet delay and average power consumption. Experiment comparisons show that the analytical results match well with the simulation results, which validates the accuracy of the analytical model. Furthermore, using the analytical model can enable us to investigate the performance tradeobetween energy efficiency and QoS requirement, and give us theoretical insight into the optimal parameters such as duty cycle, mean active period and buffer size in multi-hop wireless sensor networks.

关键词： multi-hop wireless sensor networks Markov chain energy efficiency QoS

MODELING OF FMS BASED ON UML AND OPNS

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Chinese Journal of Mechanical Engineering 2000年第2期13卷 90-95页

作者： Gao Meimei Wu Zhiming (department of Automation, shanghai jiaotong university) 上海交通大学上海

As the main component of computer integrated manufacturing system (CIMS), flexible manufacturing system (FMS) should be an open system with reusability and extenchaility. Moreover, as FMS is a complex asynchronous concurrent system, its model also should have the abilities to express the concurrency in the system and to analyze the behavior of the system. It is difficult to use any one method to model such a complex system as FMS. A modeling method using Object-oriented modeling language-unified modeling language (UML) and object-Oriented Petri nets (OPNs) is proposed. Class diagram in UML is used to represent the static relations among the objects in FMS. OPNs are used to model the dynamic behavior of the objects and conduct performance analysis. OPNs also can be used to identify the attributes and operations of the objects. The model can describe the system integrally and can be used to design FMS control software naturally.

关键词： Flexible manufacturing system Modeling Object-oriented model Unified modeling language Object-oriented Pert nets (Opens)

Network of tRNA Gene Sequences

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Journal of shanghai jiaotong university(Science) 2008年第5期13卷 611-616页

作者：韦芳萍李晟马红孺 department of physics Guangxi University Nanning Institute of Theoretical physics Shanghai Jiaotong University

A network of 3719 tRNA gene sequences was constructed using simplest alignment. Its topology, degree distribution and clustering coefficient were studied. The behaviors of the network shift from fluctuated distribution to scale-free distribution when the similarity degree of the tRNA gene sequences increases. The tRNA gene sequences with the same anticodon identity are more self-organized than those with different anticodon identities and form local clusters in the network. Some vertices of the local cluster have a high connection with other local clusters, and the probable reason was given. Moreover, a network constructed by the same number of random tRNA sequences was used to make comparisons. The relationships between the properties of the tRNA similarity network and the characters of tRNA evolutionary history were discussed.

关键词： similarity network transfer ribonucleic acid gene degree distribution clustering coefficient

Entanglement Involved in Pair Coherent State Studied via Wigner Function Formalism

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Communications in Theoretical physics 2009年第12期52卷 1071-1075页

作者： HU Li-Yun~(1,2.and FAN Hong-Yi~2. College of physics and Communication Electronics, Jiangxi Normal university, Nanchang 33002.,{2.2.department of physics, shanghai Jiao Tong university, shanghai 2.0030,{2. College of physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China department of physics Shanghai Jiao Tong University Shanghai 200030 China

We calculate Wigner function,tomogram of the pair coherent state by using its Schmidt decompositionin the coherent state *** turns out that the Wigner function can be seen as the quantum entanglement(QE)between two two-variable Hermite polynomials(TVHP)and the tomogram is further simplified as QE of twosingle-variable Hermite *** Husimi function of pair coherent state is also calculated.

关键词： pair coherent state Wigner function Tomogram Husimi function

Deriving new operator identities by alternately using normally,antinormally,and Weyl ordered integration technique

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1626-1630页

作者： FAN HongYi1,YUAN HongChun1 & JIANG NianQuan2.1department of physics,{2. Jiao Tong university,{2. 2.0030,china 2.ollege of physics and Electric Information,Wenzhou university,Wenzhou 32.035,china 1. department of physics Shanghai Jiao Tong University Shanghai 200030 China2. College of Physics and Electric Information Wenzhou University Wenzhou 325035 China

Dirac's ket-bra formalism is the language of quantum *** have reviewed how to apply Newton-Leibniz integration rules to Dirac's ket-bra projectors in previous *** this work,by alternately using the technique of integration within normal,antinormal,and Weyl ordering of operators we not only derive some new operator ordering identities,but also deduce some new integration formulas regarding Laguerre and Hermite *** may open a new route of directly deriving some complicated mathematical integration formulas by virtue of the quantum mechanical operator ordering technique,without really performing the integrations in the ordinary way.

关键词： operator ordering identities Laguerre and Hermite polynomials the IWOP technique

Traveling－Wave　Electrooptical　Modulator　on　Polymeric　Film　with　Reversal　Poling　Structure

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Chinese Journal of Lasers 1994年第1期B3卷 57-61页

作者： ZHOU Yi CHEN Yixin(department of Applied physics, {2. Jiao Tong university, {2.2.0030, china)SUN Shiping(department of Electronical Engineering ,{2. Jiao Tong university , {2. 2.0052. china) shanghai jiaotong Univ Shanghai China

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关键词： reversal poling Electrooptical effect modulator

On SS-quasinormal subgroups and the structure of finite groups

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Science china Mathematics 2011年第3期54卷 449-456页

作者： WEI XianBiao1,2.& GUO XiuYun2. 1department of Mathematics and physics, Anhui Institute of Architecture and Industry, Hefei 2.002.,{2. 2.0} of Mathematics, shanghai university, shanghai 2.0444,{2. 1. department of Mathematics and physics Anhui Institute of Architecture and Industry Hefei 230022 China2. Department of Mathematics Shanghai University Shanghai 200444 China

A subgroup H of a finite group G is said to be an SS-quasinormal subgroup of G if there is a subgroup B of G such that G = HB and H permutes with every Sylow subgroup of B. In this paper, we investigate the structure of a group under the assumption that every subgroup with order pm of a Sylow p-subgroup P of G is SS-quasinormal in G for a fixed positive integer m. Some interesting results related to the p-nilpotency and supersolvability of a finite group are obtained. For example, we prove that G is p-nilpotent if there is a subgroup D of P with 1 2.D| whenever p = 2.and |D| = 2.is SS-quasinormal in G, where p is the smallest prime dividing the order of G and P is a Sylow p-subgroup of G.

关键词： S-quasinormal subgroups SS-quasinormal subgroups p-nilpotent groups supersolvable groups

STUDY ON THE DYNAMIC SCHEDULING IN FMS REAL-TIME PRODUCTION ENVIRONMENT

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Chinese Journal of Mechanical Engineering 2001年第3期14卷 193-197页

作者： Yang Honghong,Wu Zhiming (department of Automation, shanghai jiaotong university) 上海交通大学自动化研究所上海

A dynamic database based dynamic scheduling system is *** the schedule is being preformed, the scheduling task data in the dynamic database is updated *** algorithm (GA) is employed for generating optimised production plan quickly and easily in response to changes on the shop floor. The current status of the shop is considered while rescheduling, and new plan is used in conjunction with the existing schedule to improve the effeciency of flexble manufacturing systems. Simulation results demonstrate the effectiveness of the proposed system.

关键词： Dynamic scheduling Dynamic database Genetic algorithms

Dispersion of Soluble Matters in Newton-dipolar Stratified Fluid and Effects of Peripheral Layer

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 236-241页

作者： Zhangji LU, Shousheng DONG, Yu SHEN and Guangping ZHENG (department of Mechanics and Engineering Science, Fudan university, {2. 2.0433,china)(department of physics, East china Normal university, {2. 2.0062. china) Dept. of Mechanics and Eng. Science Fudan University Shanghai 200433 China department of physics East China Normal University Shanghai 200062 China

In the paper, the dispersion law and the concentration distributions of soluble matters in Newton-dipolar fluids flowing through a circular tube have been investigated. Main results are: (1) for the dependence of M on A (or H), the completely opposite trends are obtained in the cases with and without the peripheral layer. (2. effects of δ on　M have the minimum values near 8=0.85-0.9. (3) various models such as couple stress,micropolar, dipolar, Newton-newtonian, Newton-couple stress and Newton-micropolar　model etc. are all special cases of Newton-dipolar fluid (where Mz=0). WhenMz≠ 0,however, there are evident differences between the Newton-dipolar fluid and the Newtoncouple stress fluid, the Newton-micropolar fluid.

关键词： dipolar fluid dispersion effects of a peripheral layer tube flow of complex fluid