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On power allocation for a cognitive radio network with hybrid spectrum sharing

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science china(information sciences) 2011年第11期54卷 2425-2434页

作者： ZHANG Jing 1,2,3 & ZHU HongBo 1 1 Key Laboratory of Wireless Communications of Jiangsu Province,nanjing university of Posts & Telecommunications,nanjing 210003,china 2 College of Electronic science & Engineering,nanjing university of Posts & Telecommunications,nanjing 210003,china 3 State Key Laboratory of Millimeter Waves,nanjing 210096,china Key Laboratory of Wireless Communications of Jiangsu Province Nanjing University of Posts & Telecommunications Nanjing China College of Electronic science & Engineering Nanjing University of Posts & Telecommunications Nanjing China State Key Laboratory of Millimeter Waves Nanjing China

In this study we propose a hybrid spectrum sharing scheme based on power control by combining Overlay with Underlay schemes,to improve radio spectrum *** the scheme,the secondary users dynamically switch their operational states between Overlay and Underlay according to the spectrum *** the dynamics of the primary network is first modeled with a discrete-state Markov process to find the time fraction of secondary users in the Overlay state and that in the Underlay state,which leads to the capacity model of the hybrid spectrum sharing *** the criterion of maximizing capacity,the power allocation of the cognitive network is researched and the optimum power allocation for secondary users is *** a result,the maximum achievable capacity of the cognitive network is *** are given to prove the analysis *** and simulated results indicate that hybrid spectrum sharing based on power control provides a higher capacity than single Overlay and Underlay systems for the cognitive network,i.e.,hybrid spectrum sharing can further improve radio spectrum efficiency.

关键词： cognitive radio network hybrid spectrum sharing primary network dynamics power allocation achievable capacity

Application of Fourier Slice Theorem in Wigner Operator Theory and New Complete Representation

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Communications in Theoretical physics 2009年第11期52卷 829-831页

作者： WANG Tong-Tong~1 and FAN Hong-Yi~(2,3)1 school of mathematics and physics, Huangshi Institute of technology, Huangshi 435003, china2 Department of Material science and Engineering, university of science and technology of china, Hefei 230026, china3 Department of physics, Shanghai Jiao Tong university, Shanghai 200030, china school of mathematics and physics Huangshi Institute of Technology Huangshi 435003 China Department of Material science and Engineering University of Science and Technology of China Hefei 230026 China Department of physics Shanghai Jiao Tong University Shanghai 200030 China

By applying the Fourier slice theorem,S;（λ）=∫;P;（t）e;=F（λcosθ,λsinθ）,where P;（t）is aprojection of f（x,p）=（?）F（u,v）e;dudv along lines of constant,to the Wigner operator we are naturally led toa projection operator（pure state）,which results in a new complete *** Weyl orderimg formalism of theWigner operator is used in the derivation.

关键词： Wigner operator Fourier slice theorem new complete representation

B→Xsγ, Xsl+l~-Decays and Constraints on Mass Insertion Parameters in MSSM

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Communications in Theoretical physics 2006年第10期46卷 687-696页

作者： XIAO Zhen-Jun,~+ LI Feng-Ying, and ZOU Wen-Jun Department of physics and Institute of Theoretical physics, nanjing Normal university, nanjing 210097, china Department of physics and Institute of Theoretical physics Nanjing Normal University Nanjing 210097 China

In this paper, we study the upper bounds on the mass insertion parameters (δ~q)in the minimal supersymmetric standard model. We found that the information from the measured branching ratio of B→Xl+l~-decaycan help us to improve the upper bounds on the mass insertions parameters(δ. Some regions allowed by thedata of Br(B→Xγ)are excluded by the requirement of an SM-like C(m)imposed by the data of Br(B→Xl+l~-).

关键词： B meson decay the minimal supersymmetric standard model mass insertion

Turbulence modulation model for gas–particle flow based on probability density function approach

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Chinese physics B 2017年第8期26卷 235-241页

作者：王路徐江荣 school of Energy and Power Engineering Nanjing University of Science and Technology Department of physics Hangzhou Dianzi University

he paper focuses on the turbulence modulation problem in gas–particle flow with the use of probability density function（PDF） approach. By means of the PDF method, a general statistical moment turbulence modulation model without considering the trajectory difference between two phases is derived from the Navier–Stokes equations. A new turbulence production term induced by the dispersed-phase is analyzed and considered. Furthermore, the trajectory difference between two media is taken into account. Subsequently, a new k–ε turbulence modulation model in dilute particle-laden flow is successfully set up. Then, the changes to several terms, including the turbulence production, dissipation, and diffusion terms, are well described consequently. The promoted model provides a more probable explanation for the modification of particles on the turbulence. Finally, we applied the model to simulate a gas–particle turbulence flow case in a wall jet, and found that the simulation results agree well with the experimental data.

关键词： turbulence modulation model PDF approach gas-particle flow turbulence flow

Hybrid of comprehensive learning particle swarm optimization and SQP algorithm for large scale economic load dispatch optimization of power system

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science china(information sciences) 2010年第8期53卷 1566-1573页

作者： WANG Yu , LI Bin & YUAN Bo Department of Electronic science and technology, school of information science and technology, university of science and technology of china, Hefei 230027, china Department of Electronic science and technology School of Information Science and Technology University of Science and Technology of China Hefei China

Economic load dispatch (ELD) is an important optimization task in power systems. In the previous works, various researchers attempted to address this problem by both mathmatical and heuristic optimization algorithms. However, there are still two practically important issues that have not attracted sufficient attention: 1) the stability of these algorithms cannot be effectively ensured; 2) the performance of these algorithms on large scale ELD optimization tasks remains to be unsatisfactory. CLPSO is an effective global optimization algorithm. To strengthen the convergence ability of CLPSO, the sequential quadratic programming (SQP) is introduced into it. This results in a new algorithm hybrid of comprehensive learning particle swarm optimization and sequential quadratic programming (SQP-CLPSO). To assess the performance of SQP-CLPSO, it is compared with several state-of-the-art evolutionary algorithms (EAs) on the classical ELD optimization problems. Experimental results show that SQP-CLPSO has very good abilities of convergence, diversity maintainence and scalability, which make it suitable for complex ELD problems.

关键词： particle swarm optimization comprehensive learning particle swarm optimization sequential quadratic programming local search power systems economic load dispatch

Image space analysis for variational inequalities with cone constraints and applications to traffic equilibria

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science china mathematics 2012年第4期55卷 851-868页

作者： LI Jun 1,& HUANG nanjing 2 1 College of mathematics and information,china West Normal university,Nanchong 637009,china 2 Department of mathematics,Sichuan university,Chengdu 610064,china College of mathematics and information China West Normal University Nanchong China Department of mathematics Sichuan University Chengdu China

In this paper,the image space analysis (for short,ISA) is employed to investigate variational in- equalities (for short,VI) with cone *** separation for VI with cone constraints is characterized by using the normal cone to a regularization of the image,and saddle points of the generalized Lagrangian func- ***-type necessary and sufficient optimality conditions for VI with cone constraints are presented by using a separation *** functions and weak sharpness for VI with cone constraints are also investi- ***,the obtained results are applied to standard and time-dependent traffic equilibria introduced by Daniele,Maugeri and Oettli.

关键词： variational inequality image space analysis linear separation necessary and sufficient optimalitycondition traffic equilibrium

Effect of Asymmetry in a Bistable System Subject to Multiplicative Colored Noise

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Communications in Theoretical physics 2007年第12期48卷 1059-1062页

作者： ZHOU Yu-Rong~(1,2)GUO Feng~3 and PANG Xiao-Feng~1~1 school of Life science and technology,university of Electronic science and technology of china,Chengdu 610054,china~2 school of information and Electric Engineering,Panzhihua university,Panzhihua 617000,china~3.school of Automation Engineering,university of Electronic science and technology of china,Chengdu 610054,china school of Life science and technology University of Electronic Science and Technology of China Chengdu 610054 China school of information and Electric Engineering Panzhihua University Panzhihua 617000 China school of Automation Engineering University of Electronic Science and Technology of China Chengdu 610054 China

By the method of the stochastic energetics,we investigate the stochastic resonance (SR) phenomenon of anoverdamped Brown particle in an asymmetric bistable potential,driven by external periodical signal and *** expressions have been obtained for the quasi-steady-state probability distribution *** is found thatthe input energy (IE) pumped into the system by the external driving shows an SR-like behavior as a function of thenoise strength,whereas the IE turns to be a monotonic function of the correlation time of the *** effect ofpotential asymmetry is also studied on SR and IE.

关键词： asymmetric bistable system stochastic resonance stochastic energetics

Ferroelectric properties of Bi_(3.4)Ho_(0.6)Ti_3O_(12) thin films prepared by sol-gel method

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science china(Technological sciences) 2008年第9期51卷 1439-1444页

作者： FU ChengJu1, HUANG ZhiXiong1, LI Jie2 & GUO DongYun3 1 school of Materials science and technology, Wuhan university of technology, Wuhan 430070, china 2 school of Mechanical Engineering, Chongqing university of science and technology, Chongqing 400050, china 3 Department of physics, Wuhan university, Wuhan 430072, china school of Materials science and technology Wuhan University of Technology Wuhan China school of Mechanical Engineering Chongqing University of Science and Technology Chongqing China Department of physics Wuhan University Wuhan China

We have prepared the Ho-substituted bismuth titanate (Bi3.4Ho0.6Ti3O12, BHT) thin films on Pt/Ti/SiO2/Si substrates using sol-gel method. The crystal structure and morphology of the films were characterized using X-ray diffraction and atomic force microscopy. The BHT film shows a single phase of Bi-layered Aurivillius structure and dense microstructure. The 2Pr and 2Ec of the 600-nm-thick BHT film were 38.4 μC/cm2 and 376.1 kV/cm, respectively at applied electric field 500 kV/cm. The dielectric constant and dielectric loss are about 310 and 0.015 at a frequency of 1 MHz, respectively. The Pr value decreased to 93% of its pre-fatigue values after 4.46×109 switching cycles at 1 MHz frenquency, and the BHT film shows good in-sulating behavior according to the test of leakage current.

关键词： Bi3.4Ho0.6Ti3O12 thin film sol-gel method ferroelectric property fatigue dielectric constant

C^MC^N D-computable state

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science china(physics,Mechanics & Astronomy) 2008年第9期51卷 1300-1307页

作者： LIU DongDong1,2 & DI YaoMin1 1 school of physics & Electronic Engineering,Xuzhou Normal university,Xuzhou 221116,china 2 school of mathematics & physics science,Xuzhou Institute of technology,Xuzhou 221008,china school of physics & Electronic Engineering Xuzhou Normal University Xuzhou China school of mathematics & physics science Xuzhou Institute of Technology Xuzhou China

The notions of D-computable state and D-concurrence are generalized to the CMCN system. A class of D-computable state on CMCN is given and the calculating method of the lower bound of D-concurrence is provided. Th... 详细信息

关键词： quantum entanglement entanglement of formation concurrence D-computable state