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A relative local variational principle for topological pressure

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Science china mathematics 2010年第6期53卷 1491-1506页

作者： MA XianFeng1,CHEN ErCai2.3,& ZHANG AiHua2.4 1Department of mathematics,East china University of Science and Technology,Shanghai 2.02.7,china 2.chool of mathematics and Computer Science,nanjing Normal University,nanjing 2.0097,china 3Center of Nonlinear Science,nanjing University,nanjing 2.0093,china 4college of mathematics and physics,nanjing University of {12. and telecommunications,nanjing 2.0046,china 1. Department of mathematics East China University of Science and Technology Shanghai 200237 China2. School of Mathematics and Computer Science Nanjing Normal University Nanjing 210097 China3. Center of Nonlinear Science Nanjing University Nanjing 210093 China4. College of Mathematics and Physics Nanjing University of Posts and Telecommunications Nanjing 210046 China

We define the relative local topological pressure for any given factor map and open cover,and prove the relative local variational principle of this *** precisely,for a given factor map π:(X,T)→(Y,S) between two topological dynamical systems,an open cover U of X,a continuous,real-valued function f on X and an S-invariant measure ν on Y,we show that the corresponding relative local pressure P(T,f,U,y) satisfies sup μ∈M(X,T){ hμ(T,U|Y)+∫X f(x)dμ(x) :πμ=ν}=∫Y P(T,f,U,y)dν(y),where M(X,T) denotes the family of all T-invariant measures on ***,the supremum can be attained by a T-invariant measure.

关键词： pressure conditional entropy relative local variational principle

Immune Algorithm for Solving the Optimization Problems of Computer Communication Networks

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The Journal of china Universities of posts and {2. 2000年第4期7卷 18-24页

作者： GAO Jie 1, WU Xin yu 2.(1. Department of Applied mathematics and physics, {2. University of posts and telecommunications, {2. 2.0003, P. R. china 2. Department of Electronical Engineering, {2. University of posts and telecommunications, Department of Applied mathematics and physics Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China Department of Electronical Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China

The basic problem in optimizing communication networks is to assign a proper circuit for each origin destination pair in networks so as to minimize the average network delay, and the network optimal route selection model is a multi constrained 0 1 nonlinear programming problem. In this paper, a new stochastic optimization algorithm, Immune Algorithm, is applied to solve the optimization problem in communication networks. And the backbone network vBNS is chosen to illustrate the technique of evaluating delay in a virtual network. At last, IA is compared with the optimization method in communication networks based on Genetic Algorithm, and the result shows that IA is better than GA in global optimum finding.

关键词： immune algorithm computer communication networks network delay optimal route select

Superprocesses on Two Space Forms

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The Journal of china Universities of posts and {2. 2001年第3期8卷 69-76页

作者： TANG Jia-shan (Department of Applied mathematics and physics, {2. University of posts and telecommunications, {2. 2.0003, P.R. china) Department of Applied mathematics and physics Nanjing University of Posts and Telecommunications

Superprocess is one class of measure-valued branching Markov processes. Many results of the process on abstract spaces and Euclidean spaces are obtained in the literature. In this paper, we discuss super-Brownian motions on two space forms and reveal partially the relationship between the properties of superprocesses and the geometric structure of the underlying state spaces. Finally, we also presents some open problems.

关键词： superprocess branching mechanism underlying process underlying space space form

Epidemic spreading on a scale-free network with awareness

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Chinese physics B 2012年第10期21卷 44-48页

作者：鲁延玲蒋国平宋玉蓉 college of Computer Nanjing University of Posts and Telecommunications college of Automation Nanjing University of Posts and Telecommunications

This paper presents a modified susceptible-infected-recovered（SIR） model with the effects of awareness and vaccination to study the epidemic spreading on scale-free networks based on the mean-field *** this model,when susceptible individuals receive awareness from their infected neighbor nodes,they will take vaccination *** theoretical analysis and the numerical simulations show that the existence of awareness and vaccination can significantly improve the epidemic threshold and reduce the risk of virus *** addition,regardless of the existence of vaccination,the awareness can increase the spreading threshold and slow the spreading speed *** a given awareness and a certain spreading rate,the total number of infections reduces with the increasing vaccination rate.

关键词： scale-free network awareness vaccination epidemic threshold

Organic thin-film solar cells:Devices and materials

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Science china Chemistry 2012年第4期55卷 553-578页

作者： LI ZhiGang1, ZHAO XinYan2. LI Xin1,2. GAO ZhiQiang1, MI BaoXiu1 & HUANG Wei2.1Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting and School of Materials Science & Engineering, nanjing University of posts & {2., nanjing 2.0046, china 2.ey Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM), nanjing University of posts & {2., nanjing 2.0046, china 1. Jiangsu Engineering Centre for Flat-Panel Displays & Solid-state Lighting and School of Materials Science & Engineering Nanjing University of Posts & Telecommunications Nanjing 210046 China2. Key Laboratory for Organic Electronics & Information Displays (KLOEID) Institute of Advanced Materials (IAM) Nanjing University of Posts & Telecommunications Nanjing 210046 China

In recent years, the performance of organic thinfilm solar cells has gained rapid progress, of which the power conversion efficiencies （r/p） of 3%-5% are commonly achieved, which were difficult to obtain years ago and are improving steadily now. The r/p of 7.4% was achieved in the year 2.10, and r/p of 9.2. was disclosed and confirmed at website of Mitsubishi Chemical in April, 2.11. The promising future is that the r/p of 10% is achievable according to simulation results. Apparently, these are attributed to material innovations, new device structures, and also the better understanding of device physics. This article summarizes recent progress in organic thinfilm solar cells related to materials, device structures and working principles. In the device functioning part, after each brief summary of the working principle, the methods for improvements, such as absorption increment, organic/electrode interface engineering, morphological issues, are addressed and summarized accordingly. In addition, for the purpose of increasing exciton diffusion efficiency, the benefit from triplet exciton, which has been proposed in recent years, is highlighted. In the active material parts, the chemical nature of materials and its impact on device performance are discussed. Particularly, emphasis is given toward the insight for better understanding device physics as well as improvements in device performance either by development of new materials or by new device architecture.

关键词： organic – solar cell – photovoltaic – devices – materials

Optical Properties of One-dimensional Three-component Photonic Band Gap Structure

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The Journal of china Universities of posts and {2. 2003年第2期10卷 22-26,33页

作者： CAI Xiang bao (Department of Applied mathematics and physics, {2. University of posts and telecommunications, {2. 2.0003, P.R.china National Laboratory of Solid State Microstructures, {2. University, {2. 2.0093, P.R.china) Department of Applied mathematics and physics Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China

Theoretical study of the optical properties of one dimensional three component photonic band gap structure, which is composed of three alternating dielectric layers of different refractive indices and thickness in a unit cell, is performed. This one dimensional photonic band gap structure exhibits the transparency band and forbidden band. We find that there are several mini bands of the allowed transmission to be created within the photonic band gap region of the structure if a defect designed specially is introduced inside the structure. This characteristic is very important for some practical applications.

关键词： photonic crystal photonic band gap optical property forbidden band

Improving the secrecy rate by turning foes to allies:An auction scheme

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Chinese physics B 2015年第9期24卷 80-90页

作者：马亚燕王保云 college of Communication and Information Engineering Nanjing University of Posts and Telecommunications

Security against eavesdroppers is a critical issue in cognitive radio networks（CRNs）. In this paper, a scenario consisting of one primary pair and multiple secondary pairs is considered. The secondary transmitters（STs） work in half-duplex mode and they are potential eavesdroppers on the primary transmission unless they are allowed to simultaneously transmit with the primary transmitter（PT）. A modified second-price sealed-bid auction scheme is employed to model the interaction between the PT and STs. With the proposed auction scheme, the hostile relationship between the PT and STs is transformed into a cooperative relationship. An iterative algorithm based on the max–min criteria is proposed to find the optimal bidding power of the STs for an access chance in the presence of multiple eavesdroppers. Numerical results show that the proposed auction scheme not only improves the PT＇s security but also increases the access opportunities of the STs.

关键词： security auction cooperation cognitive radio networks

Analytical Model of Non-dispersion-limited Transient Stimulated Raman Scattering in Single-mode Silica Fiber in WDM Optical Communication System

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Chinese Journal of Lasers 2000年第2期9卷 175-181页

作者： GONG Jiamin FANG Qiang LIU Juan WANG Yongchang (Insitute of Modern physics, Xi' an Jiaotang University, Xi' an 710049, china Department of {2., Xi' an Institute of posts and {2., Xi' an 710061, china ) 西安交通大学陕西西安西安邮电学院陕西西安

The non-dispersion-limited analytic acutions of unidirectional N-channel transient stimulated Raman scattering (SRS) coupling wave equation which governing the propagation of the optical signals in single-mode (SM) silica fiber have been presented. Taking into account the SRS cross coupling among the N- channels, the analytic solutions are applicable to the system with arbitrary channel separation and input signal light power.

关键词： stimulated Raman scattering (SRS) wavelength division multiplexing (WDM) fused silica fiber Raman amplification Raman crosstalk

The Effect of SRS on Signal Power in Single mode Silica Fiber in DWDM Optical Communication System with Equally Spaced Channels

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Chinese Journal of Lasers 2000年第1期9卷 52-57页

作者： GONG Jiamin 1 FANG Qiang 2. LIU Juan 2. WANG Yongchang 1 ( 1Institute of Modern physics, Xi'an JiaoTong University, Xi'an 710049,china 2.epartment of {2., Xi'an Institute of posts and {2., Xi'an 710061, C 西安交通大学陕西西安西安邮电学院陕西西安

Assuming that the Raman gain profile of silica fiber is a triangular function, we derive analytic solutions of N channel  steady state forward SRS coupling wave equation with equal (but arbitrary) channel spacing. Considering the SRS cross coupling among N channels,  the analytic solutions are applicable to arbitrary signal light power. The results point out that the sequence m i=p i(z)/p i(0) 〔p i(z) and p i(0) is the power of signal light of i th  channel at transmission length z and 0, respectively. i=1,2.…N〕 maintains a geometric progression with the common ratio q in the transmission process. The common ratio q varies as a exponential function of the effective transmission length, the sum of input light power and the channel spacing, respectively.

关键词： stimulated Raman scattering (SRS) density wavelength division multiplexing fused silica fiber