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An improved model of Robinson equivalent circuit analytical model

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science China(Technological sciences) 2010年第7期53卷 1993-1999页

作者： MAO XiangYu & DU PingAn School of Mechatronics Engineering, university of electronic {2. and technology of China, chengdu 6.1731, China School of Mechatronics Engineering University of Electronic Science and Technology of China Chengdu China

The Robinson equivalent circuit analytical model can be used only in calculating shielding effectiveness of enclosure with the same multi-holes in one wall, but cannot be used in different multi-holes in two walls. According to the practical requirement, this article uses Konefal's and Farhana's characteristic impedance of apertures to improve the equivalent circuit analytical model in different multi-holes in two walls. The improved equivalent circuit analytical model is more useful than Robinson equivalent circuit analytical model. In the article, all kinds of enclosures are simulated by TLM (Transmission-Line Matrix method) to prove that this improved model is feasible in multimode.

关键词： equivalent circuit improved model apertures shielding effectiveness TLM (Transmission-Line Matrix method)

Spray and forward:Efficient routing based on the Markov location prediction model for DTNs

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science China(Information sciences) 2012年第2期55卷 433-440页

作者： DANG Fei1,YANG XiaoLong1,2.& LONG KePing2.1 Research Center for Optical Internet and Mobile Information Networks(COIMIN),university of electronic {2. and technology of China,chengdu 6.1731,China 2.School of Computer and Communications Engineering,university of {2. and technology Beijing,Beijing 100083,China Research Center for Optical Internet and Mobile Information Networks (COIMIN) University of Electronic Science and Technology of China School of Computer and Communications Engineering University of Science and Technology Beijing

Typical delay tolerant networks(DTNs)often suffer from long and variable delays,frequent connectivity disruptions,and high bit error *** DTNs,the design of an efficient routing algorithm is one of the key *** existing methods improve the accessibility probability of the data transmission by transmitting many copies of the packet to the network,but they may cause a high network *** address the tradeoff between a successful delivery ratio and the network overhead,we propose a DTN routing algorithm based on the Markov location prediction model,called the spray and forward routing algorithm(SFR).Based on historical information of the nodes,the algorithm uses the second-order Markov forecasting mechanism to predict the location of the destination node,and then forwards the data by greedy routing,which reduces the copies of packets by spraying the packets in a particular *** contrast to a fixed mode where a successful-delivery ratio and routing overhead are contradictory,a hybrid strategy with multi-copy forwarding is able to reduce the copies of the packets efficiently and at the same time maintain an acceptable successful-delivery *** simulation results show that the proposed SFR is efficient enough to provide better network performance than the spray and wait routing algorithm,in scenarios with sparse node density and fast mobility of the nodes.

关键词： delay tolerant networks spray and forward Markov position prediction routing algorithm

Influence of Pr Content on the Sructure and Giant Magnetoresistance of Pr_x(Co_(40)Ag_(6.))_(100-x) Granular Films

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Journal of Wuhan university of technology(Materials {2.) 2011年第1期26卷 1-3页

作者：成钢 School of Materials science and Engineering Guilin University of Electronic Technology Guangxi Key Laboratory of Information Materials

Prx（Co40Ag6.）100-x （x=0, 0.5, 1, 1.5, 2. 3） granular films have been prepared by DC magneto controlled sputtering method. The XRD data indicated that Pr element favors the （111） plane preferential orientation. Magnetic measurements indicate that the average size of magnetic particles decreases as Pr content increases. For relatively low addition of Pr to CoAg granular films, Pr element can enhance GMR value and a peak value of about -14.3% is obtained at x=1.

关键词： giant magnetoresistance granular films magnetic particle

Effects of pH on the peripheral light-harvesting antenna complex for Rhodopseudomonas palustris

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science China(Life sciences) 2008年第8期51卷 760-766页

作者： FENG Juan, LI XueFeng & LIU Yan School of Life science and technology, {2. of electronic science and technology of China,{6., China School of Life science and technology University of Electronic Science and Technology of China Chengdu China

In this work steady-state absorption spectroscopy, circular dichroism spectroscopy and sub-micro-second time-resolved absorption spectroscopy were used to investigate the effect of pH on the struc-tures and functions of LH2.complex for Rhodopseudomonas palustris. The results revealed that: (1) B800 Bchla was gradually transformed to free pigments absorbing around 76. nm on the minutes timescale upon the induction of strong acidic pH, and subsequently there disappeared the CD signal for Qy band of B800 in the absence of B800. In addition, Carotenoids changed with the similar tendency to B850 BChl. (2. The introduction of strong basic pH gave rise to no significant changes for B800 Bchla, while B850 BChla experienced remarkable spectral blue-shift from 852.to 837 nm. Similar phe-nomenon was seen for the CD signal for Qy band of B850. Carotenoids displayed strong and pH-independent CD signals in the visible range. (3) In the case of both physiological and basic pH, broad and asymmetrical positive Tn←T1 transient absorption appeared following the pulsed photo-excitation of Car at 532.nm. By contrast, the featureless and weak positive signal was observed on the sub-microsecond timescale in the acidic pH environment. The aforementioned experimental results indicated that acidic pH-induced removal of B800 Bchla prevented the generation of the caro-tenoid triplet state (3Car*), which is known to be essential for the photo-protection function. Neverthe-less, carotenoids can still perform this important physiological role under the basic pH condition, where the spectral blue shift of B850 exerts little effect on the overall structure of the cyclic aggregate, therefore favoring the formation of carotenoid triplet state.

关键词： pH-induced B800-removal triplet state photo-protection function

Towards a Methodology for Formal Design and Analysis of Agent Interaction Protocols ——An Investigation in electronic Commerce

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Wuhan university Journal of Natural sciences 2001年第Z1期6卷 126-139页

作者： Wei Jun 1,2., Cheung Shing Chi 1, Wang Xu 1 1. Department of Computer science, Hong Kong university of science and technology, Clear Water Bay, Kowloon, Hong Kong, China 2. Institute of Software, Chinese Academy of science, Beijing 100080, Ch Department of Computer science Hong Kong University of Science and Technology Kowloon Hong Kong China Institute of Software Chinese Academy of Science Beijing China

Various extensions of UML have been developed to meet the challenges of designing modern software systems, such as agent based electronic commerce applications. Recent advances in model checking technology have led it to be introduced into the development of approaches and tools to check the correctness of electronic commerce protocols. This paper focuses on the research of a method that connects an extension of AUML to model checker SPIN/Promela for the specification and verification of agent interaction protocols (AIP) in electronic commerce. The method presented here allows us to combine the benefits of visual specification with the power of some static analysis and model checking. Some algorithms and rules are developed to permit all visual modeling constructs translated mechanically into some Promela models of AIP, as supported by the model checker SPIN. Moreover, a process is illustrated to guide the specification and verification of AIP. The method is demonstrated thoroughly using the e commerce protocol NetBill as an example.

关键词： agent UML interaction protocol software agent model checking formal specification electronic commerce protocol

Effects of NaNbO_3-Co_2._3 Co-additive on the Properties of PZN-PZT Ceramics

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Journal of Wuhan university of technology(Materials {2.) 2007年第4期22卷 722-724页

作者：邓毅华 College of Material science and Engineering South China University of Technology Department of electronic science and {2. Huazhong University of Science and TechnologyWuhan 430074China

NaNbO3-Co2.3 co-added PZN-PZT （PZCNNT） ceramics were prepared using conventional solid state reaction. The piezoelectric and dielectric properties were measured. The experimental results show that the addition of 0.3mo1% Co2.3 leads to low dielectric loss （tgδ） in PZCNNT ceramics and the proper addition of NaNbO3 not only improves piezoelectric properties but also decreases intensively dielectric loss and mechanical loss. The optimal ceramic having d33=310 pC/N, kp=0.59, εr=985, tgδ=0.0034, Qm=1380 was obtained.

关键词： PZN-PZT piezoelectric constant dielectric constant dielectric loss

A New Process and Framework for Direct Anonymous Attestation Based on Symmetric Bilinear Maps

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Wuhan university Journal of Natural sciences 2011年第5期16卷 369-375页

作者： TAN Liang1,2. ZHOU Mingtian3 1. College of Computer/Key Lab of Visualization in Scientific Computing and Virtual Reality of Sichuan, Sichuan Normal university, chengdu {2.00{2., Sichuan, China 2. Institute of Computing {2., Chinese Academy of sciences, Beijing 100190, China 3. School of Computer science and Engineering, university of {{2. science and {2. of China, chengdu 6.0054, Sichuan, China College of Computer/Key Lab of Visualization in Scientific Computing and Virtual Reality of Sichuan Sichuan Normal University Chengdu Sichuan China Institute of Computing technology Chinese Academy of Sciences Beijing China School of Computer science and Engineering University of Electronic Science and Technology of China Chengdu Sichuan China

For the problem of the original direct anonymous attestation （DAA） scheme＇s complexity and great time consumption, a new DAA scheme based on symmetric bilinear pairings is presented, which gives a practical solution to ECC-based TPM in protecting the privacy of the TPM. The scheme still includes five procedures or algorithms： Setup, Join, Sign, Verify and Rogue tagging, but gets rid of zero-knowledge proof and takes on a new process and framework, of which the main operations are addition, scalar multiplication and bilinear maps on supersingular elliptic curve systems. Moreover, the scheme adequately utilizes the properties of bilinear maps as well as the signature and verification of the ecliptic curve system itself. Compared with other schemes, the new DAA scheme not only satis- fies the same properties, and shows better simplicity and high effi- ciency. This paper gives not only a detailed security proof of the proposed scheme, but also a careful performance analysis by comparing with the existing DAA schemes.

关键词： direct anonymous attestation bilinear map privacy authentication trusted computing platform trusted platform module

electronic Structure of Doped Trans-Polyacetylene

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Wuhan university Journal of Natural sciences 2002年第1期7卷 51-53页

作者： Ren Da-zhi 1,2. Zhuang Wei 2. Wang Jun 2.1. Wuhan university Journals Press,Wuhan 430072.Hubei,China 2. School of Physics and technology, Wuhan university, Wuhan 430072.Hubei,China Wuhan university Journals Press Wuhan Hubei China School of Physics and technology Wuhan University Wuhan Hubei China

The behavior of electronic structures of doped trans-polyacetylene is revealed by a simple method. (C2.H2.1}+n is used to simulate p-type doped trans-polyacetylene at various doping concentrations. The electronic structure is calculated, by CNDO/2.method. These calculations show that at low doping level, the decrease of electronic energy compensates the increase of elastic energy, thus the bond alternation exists, and the charge carriers are solitons. When doping level is high, the increase of elastic energy is larger than the decrease, of electronic energy, the bond alternation disappears, solitons no longer exist, and polyacetylene is in a metalic state.

关键词： trans polyacetylene CNDO/2 electronic structure doped

Kinetics analysis of volume phase transition of intelligent neutral thermo-sensitive hydrogels

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science China(Physics,Mechanics & Astronomy) 2008年第5期51卷 532-540页

作者： WANG XiaoGui1 & LI YiQuan2.1 College of Mechanical Engineering,Zhejiang university of technology,Hangzhou 310032.China 2.School of Mechanical & {2. Engineering,Changchun university of science and technology,Changchun 13002.,China College of Mechanical Engineering Zhejiang University of Technology Hangzhou China School of Mechanical & electronic Engineering Changchun University of Science and Technology Changchun China

In this work,utilizing the first law of thermodynamics and the Flory mean-field theory,the kinetic deformation studies concerning the volume phase transition of the neutral thermo-sensitive hydrogels were performed *** hydrogel was assumed as a biphasic mixture medium in the framework of the continuum mixture *** the energy conservation of the thermodynamics system of the hydrogel,the governing equations for the kinetics of the nonlinear large deforma-tion were *** explicit analytical expressions of the effective stress tensor and the chemical potential of the fluid of the thermo-sensitive hydrogel PNIPA were also obtained from the Helmholtz free energy,which can model the steady-static volume phase transition quantitatively.

关键词： thermo-sensitive hydrogel volume phase transition effective stress energy conservation