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水电能源科学 2011年第6期29卷 140-142页

作者：任杰宁夏大学土木与水利工程学院宁夏银川750021 宁夏节水灌溉与水资源调控工程技术研究中心宁夏银川750021 旱区现代农业水资源高效利用工程研究中心宁夏银川750021

为有效提高提水灌区水资源利用效率,基于水价计算及水费收取问题,以宁夏引黄灌区为例,依据《水利工程供水价格管理办法》,采用完全成本定价法评价了水资源价值,并测算了宁夏某灌区水价,为灌区水价管理提供了依据。

关键词：提水灌区水价计算方法宁夏

Extended multivariate public key cryptosystems with secure encryption function

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Science china(Information Sciences) 2011年第6期54卷 1161-1171页

作者： WANG HouZhen 1,2., ZHANG HuanGuo 1,2., WANG ZhangYi 1,2.& TANG Ming 1,2.1 The Key Laboratory of Aerospace Information Security and Trusted Computing, Ministry of Education, School of Computer, Wuhan university, Wuhan 430079, china 2.State Key Laboratory of Software {2., Wuhan university, Wuhan 430072. china 1. The Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education School of Computer Wuhan University Wuhan 430079 China2. State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China

Advances in quantum computers pose great threats on the currently used public key cryptographic algorithms such as RSA and ECC. As a promising candidate secure against attackers equipped with quantum computational power, multivariate public key cryptosystems (MPKCs) have attracted increasing attention in recently years. Unfortunately, the existing MPKCs can only be used as a multivariate signature scheme, and it remains unknown how to construct an efficient MPKC enabling secure encryption. Furthermore, some multivariate signature schemes have been shown insecure in recent years, and it is also not trivial to build MPKC which can serve as a secure signature scheme. By employing the basic MQ-trapdoors, this paper proposes a novel MPKC and shows how it can be used as a multivariate signature scheme and a multivariate encryption scheme, respectively. The goal is achieved by incorporating our new hash authentication techniques and some modification methods such as the Shamir's minus method. Thorough analysis shows that our schemes are secure and efficient. Our MPKC gives a positive response to the challenges in multivariate public key cryptography.

关键词： cryptography post-quantum cryptography MQ problem hash function

Power allocation scheme for selfish cooperative communications based on game theory and particle swarm optimizer

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Science china(Information Sciences) 2010年第9期53卷 1908-1912页

作者： ZHANG GuoPeng1*,YANG Kun2.& DING EnJie3 1School of Computer Science and Technology,china university of Mining and Technology,Xuzhou 2.1116,china 2.chool of Computer Science and Electronic engineering,university of Essex Wivenhoe Park,Colchester CO_4 3SQ,UK 3School of Information and Electrical engineering,china university of Mining and Technology,Xuzhou 2.1116,china 1. School of Computer Science and Technology China University of Mining and Technology Xuzhou 221116 China2. School of Computer Science and Electronic Engineering University of Essex Wivenhoe Park Colchester CO4 3SQ UK3. School of Information and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China

In commercial networks,autonomous user nodes operating on batteries are assumed to be selfish to consume their energy solely to maximize their own benefits,e.g.,data *** this letter a two-user cooperative game is proposed to perform the power allocation for selfish cooperative communication *** the game,one selfish user node could trade its transmission power for the other ones cooperative relaying directly,and both user nodes are willing to achieve an optimal data-rate increase through cooperative *** find the Nash bargaining solution(NBS) of the game,a low-complexity numerical particle swarm optimizer(PSO) algorithm is also *** results indicate that the NBS of the game is efficient,in that both users could experience better performance than they work independently,and fair,in that the degree of cooperation of a user node only depends on how much contribution its partner can make to improve its own performance.

关键词： cooperative communication power allocation game theory Nash bargaining solution particle swarm optimizer

Interpolating triangular meshes by Loop subdivision scheme

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Science china(Information Sciences) 2010年第9期53卷 1765-1773页

作者： DENG ChongYang1* & WANG GuoZhao2.1Institute of Applied Mathematics and engineering Computations,Hangzhou Dianzi university,Hangzhou 310018,{2. 2.epartment of Mathematics,Zhejiang university,Hangzhou 31002.,{2. 1. Institute of Applied Mathematics and engineering Computations Hangzhou Dianzi University Hangzhou 310018 China2. Department of Mathematics Zhejiang University Hangzhou 310027 China

Using the limit point formula of the Loop subdivision scheme,we propose a very simple and efficient method for constructing interpolation surface of triangular meshes by Loop subdivision *** excellent properties of the method are:(1) Locality:the perturbation of a given vertex only influences the surface shape near this vertex.(2. Efficiency:the locations of new points can be computed with explicit formulae.(3) Easiness in implementation:only the geometric rule of the first step should be modified.(4) Freedom:for each edge,there is one degree of freedom to adjust the shape of the interpolation surface.(5) Easiness in generalization:it is easy to generalize our method to other approximation subdivision schemes with explicit formulae to compute limit point.

关键词： computer aided geometric design subdivision surface approximating subdivision scheme Loop surface surface interpolating

THE VELOCITY FIELD OF MULTIPHASE FLOW AND EFFICIENCY OF BIOLOGICAL AERATION FILTER

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Journal of Hydrodynamics 2010年第2期22卷 260-264页

作者： CHENG Wen HU Bao-wei YANG Chun-di CHENG Wen-juan Environment research Institute Xian University of Technology Xi＇an 710048 China State Key Laboratory of Multiphase Flow in Power engineering Xi＇ an Jiaotong University Xi＇an 710049 China Key Laboratory of Northwest water resources and Environmental Ecology of Education Ministry Xi＇anUniversity of Technology Xi＇an 710048 China Yuanpei College Shaoxing University Shaoxing 312000 China Environment research Institute Xi＇an University of Technology Xi＇an 710048 China

Aeration is an important factor affecting the biological aeration *** a set of experiment device specially designed for the purpose,and the particle image velocimetry technique,the velocity field of the gas-liquid two-phase flow is studied under different *** various simulated aeration states were actually applied to the experimental device of sewage treatment,and the results of the numerical simulation were *** final experimental results indicate that the most efficient state occurs when the ratio of water in aeration tank h / w =1,the diameter of capillary tubes d=0.6mm and the velocity of bubbles v=0.3m/s.

关键词： ratio of water diameter of capillary tube bubbles velocity sewage disposal efficiency

Spontaneous chiral-symmetry breaking of lattice QCD with massless dynamical quarks

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Science china(Physics,Mechanics & Astronomy) 2007年第1期50卷 6-14页

作者： LUO XiangQian Department of Physics,School of Physics and engineering,Sun Yat-Sen university,Guangzhou 5102.5,{2. 1. Department of Physics School of Physics and Engineering Sun Yat-Sen University Guangzhou 510275 China

One of the most challenging issues in QCD is the investigation of spontaneous chiral-symmetry breaking, which is characterized by the non-vanishing chiral condensate when the bare fermion mass is zero. In standard methods of the lattice gauge theory, one has to perform expensive simulations at multiple bare quark masses, and employ some modeled functions to extrapolate the data to the chiral limit. This paper applies the probability distribution function method to computing the chiral condensate in lattice QCD with massless dynamical quarks, without any ambiguous mass extrapolation. The results for staggered quarks indicate that this might be a promising and efficient method for investigating the spontaneous chiral-symmetry breaking in lattice QCD, which deserves further investigation.

关键词： lattice QCD spontaneous chiral-symmetry breaking dynamical quarks

Energy efficient Beacon Discovering Scheme for Node Localization in Wireless Sensor Networks

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Wuhan university Journal of Natural Sciences 2010年第4期15卷 303-307页

作者： LIU Xinxin1,2. ZHAO Erdun3, CHEN Kun2.1. School of Computer, Wuhan university, Wuhan 430072. Hubei, china 2. Wuhan Digital {2. research Institute, Wuhan 430074, Hubei, china 3. Department of Computer Science, Huazhong Normal university, Wuhan 430079, Hubei, china School of Computer Wuhan University Wuhan Hubei China Wuhan Digital engineering research Institute Wuhan Hubei China Department of Computer Science Huazhong Normal University Wuhan Hubei China

efficient sensor node localization is a crucial part of many location-dependent applications that utilize wireless sensor networks (WSNs). To cope with the problem of insufficient bea-con node for localization,we design a beacon discovery protocol in this paper that helps the blind node to find beacons nearby and present an energy efficient scheme for the beacon that receives the request from a blind node to adjust its radio range. We obtain the relationship between the mean energy consumption with adjust-ment number by the mathematical analysis. Numerical results show that great energy saving is achieved when the optimal ad-justment number is adopted.

关键词： localization wireless sensor networks energy- efficient radio range adjustment

Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

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Science china(Information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2.SUN LiXin 1,LI Yong 2.& JIA ShiLou 3 1 School of Computer Science and Telecommunication engineering,Jiangsu university,Zhenjiang 2.2.13,{2. 2.research Center for Wireless Communication,Shanghai Institute of Microsystem and Information Technology,Chinese Academy of Sciences,Shanghai 2.0050,{2. 3 Communication research Center,Harbin Institute of Technology,Harbin 150001,{2. 1. School of Computer Science and Telecommunication engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

A new principle of synthetic cascade utilization of chemical energy and physical energy

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Science china(Technological Sciences) 2005年第2期48卷 163-179页

作者： JIN Hongguang1, HONG Hui1,2. WANG Baoqun1,2. HAN Wei1,2.& LIN Rumou1,2.1. Institute of engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, china 2. Graduate School of the Chinese Academy of Sciences, Beijing 100039, china 1. Institute of engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the Chinese Academy of Sciences 100039 Beijing China

We propose a new principle of the cascade utilization of both chemical energy and physical energy in energy systems with the integration of chemical processes and thermal cycles. Particularly, a general equation of energy levels of substance, Gibbs free energy of chemical reaction and physical energy is explicitly founded. On the basis of this equation, a chemical-looping combustion and an indirect combustion are investigated. Furthermore, a mechanism of energy release, with the combination of decreasing the energy level of Gibbs free energy and upgrading the energy level of low or middle- temperature thermal energy, is clarified. The promising results obtained here establish a theoretical basis for the further investigation of multi-function systems in which energy and the environment are compatible, and create a new approach to improve the performance of traditional thermal cycles.

关键词： chemical energy, cascade utilization, exergy, energy conversion.

θ-PSO: a new strategy of particle swarm optimization

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Journal of Zhejiang university-Science A(Applied Physics & engineering) 2008年第6期9卷 786-790页

作者： Wei-min ZHONG1,2. Shao-jun LI1,2. Feng QIAN1,2.(1State Key Laboratory of Chemical engineering, East china {2. of Science and Technology, Shanghai 2.02.7, china) (2.utomation Institute, East china {2. of Science and Technology, Shanghai 2.02.7, china) State Key Laboratory of Chemical engineering East China University of Science and Technology Shanghai China Automation Institute East China University of Science and Technology Shanghai China

Particle swarm optimization (PSO) is an efficient, robust and simple optimization algorithm. Most studies are mainly concentrated on better understanding of the standard PSO control parameters, such as acceleration coefficients, etc. In this paper, a more simple strategy of PSO algorithm called θ-PSO is proposed. In θ-PSO, an increment of phase angle vector replaces the increment of velocity vector and the positions are decided by the mapping of phase angles. Benchmark testing of nonlinear func- tions is described and the results show that the performance of θ-PSO is much more effective than that of the standard PSO.

关键词： Particle swarm optimization (PSO) Phase angle Benchmark function