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A new generation of plastic optical fibers and its functional exploiting

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Science china(Technological Sciences) 2008年第12期51卷 2197-2207页

作者： YU RongJin & ZHANG Bing college of information Science and engineering,Yanshan university,Qinhuangdao 066004,china college of information Science and engineering Yanshan University Qinhuangdao 066004 China

A major problem of plastic optical fibers(POFs) is large transmission loss in comparison with silica *** adopting a new optical fiber structure,hollow-core Bragg fiber with cobweb-structured cladding,which can suppress the absorption losses of constituent materials by a factor of about 104―106,the problem of POFs with large losses is solved *** the advantage of flexibility and easy bending,the POFs with this structure can guide light with low transmission loss for information and energy in the wavelength range of visible light to terahertz(THz) wave(0.4―1000 μm).This new generation of POFs will find many applications.

关键词： plastic optical fiber hollow-core Bragg fiber cobweb-structured cladding visible light infrared light terahertz wave circular-polarization single-mode

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5.1 college of Computer Science and technology,Beijing university of technology,Beijing 100022,china 2 State Key Laboratory of {5. Security (Graduate university of the Chinese Academy of Sciences),Beijing 100049,china 3 School of Science,Beijing university of Posts and Telecommunications,Beijing 100876,china 4 Institute of Electronic technology,{5. engineering university,Zhengzhou 45.004,china 5.Trusted Computing Laboratory,Beijing university of technology,Beijing 100022,china college of Computer Science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of information Security [Graduate university of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Investigation of 'chazi'(damaged-enamels)on Chenghua doucai Porcelains

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Science china(Technological Sciences) 2009年第6期52卷 1722-1729页

作者： DU Feng1 & SU BaoRu2 1 Institute of Chemistry & Molecular engineering,Qingdao university of Science & technology,Qingdao,china 2 college of {5. Science & technology,Qingdao university of Science & technology,Qingdao,china Institute of Chemistry & Molecular engineering Qingdao University of Science & Technology Qingdao China college of information Science & technology Qingdao University of Science & Technology Qingdao China

At the end of the 195.s,Sun Yingzhou considered that the 'chazi'(damaged colour)on Chenghua doucai imperial porcelain as a defect was originally produced in firing process during Chenghua period(1465.1487).Researchers in china have accepted his *** any fragment with the 'chazi' has never been found in several tons of Chenghua imperial sherds excavated from Ming imperial kiln site in *** china,few scholars have questioned the formation of 'chazi',and further investigated *** researchers at the Research Laboratory in the British Museum,employing unde-structive EDXRF,have analyzed the chemical composition of the 'chazi'(damaged colour)on a Chen-ghua doucai stem cup in the museum,and they have confirmed that the 'chazi'(damaged colour)was caused by the fire of the Jianfu palace in the Forbidden City in *** on their research,the authors studied the colour chemical principle of the 'chazi's' formation *** to the ceramic technology principle,scientific reasoning for the 'chazi' was carried *** the help of the history of Qing court,the brainteaser of the 'chazi' was totally uncovered,the misunderstanding for the 'chazi' has also been *** research also suggests that employing modern science and technology is a direction to study Chinese ancient ceramic further.

关键词： Chenghua doucai porcelains court eunuchs the set on fire at the Jianfu palace ’chazi’(damaged-enamels) the British Museum colour chemical principle archaeology using science and technology

Study on Syntheses and Characterizations of Polymethylphenethylsilane, Polymethylcyclohexylsilane and their Copolymers

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Journal of Central South university 2000年第2期12卷 92-96页

作者： HU Hui ping 1,HUANG Ke long 1,PAN Chun yue 1,CHEN De ben 2 (1 college of Chemistry and Chemical engineering, Central South university of technology, Changsha 410083, china 2 Department of Chemistry,{5. university, chengdu 610064, china 1. college of Chemistry and Chemical engineering Central South University of Technology 410083 Changsha China 2. Department of Chemistry Sichuan University 610064 Chengdu China

The effects of adding cosolvents of diglyme and 15.crown-5.to the reaction mixture of Wurtz-type coupling of dichlorosilanes on the yield and relative molecular mass dispersity of polymethylphenethylsilane(PMPES) were discussed. The results show that addition of 10%(volume ratio of diglyme to toluene) diglyme as a cosolvent to the reaction mixture leads to the yield increase of PMPES with a monomodal distribution of relative molecular masses. Adding 10%diglyme to the reaction mixtures, the yields of polymethylcyclohexylsilane(PMCS) and copolymers (polymethylphenethylsilane-co-methylcyclohexylsilane), (the molar ratios of methylphenethyldichlorosilane to methylcyclohexyldichlorosilane were 2.0, 1.0 and 0.5. and the copolymers were abbreviated by Copolymers I, II, III, respectively) are 47%, 5.%, 5.%, 5.%, respectively. Their relative molecular masses ([`(M)]w )(\bar M_w ) almost reach 105. These polysilanes were characterized by 1H-NMR, IR and UV absorption spectrum.

关键词： polysilane cosolvent synthesis characterization

MINIMUN TIME OPTIMAL CONTROL OF STEPPING MOTOR

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Journal of Central South university 1995年第2期7卷 54-58页

作者： Luo An(college of information engineering, Central South university of technology, Changsha, 410083,{5.) 1. college of information engineering Central South University of Technology 410083 Changsha China

The paper describes a new method of the stepping motor moimun time optimal control with closed-loop control. A mathematical model and optimal control strategy for the optimal control of stepping motor are proposed. ... 详细信息

关键词： optimal control stepping motor microcomputer

Graphics Processor Unit （GPU） acceleration of Time-Domain Finite Element Method （TD-FEM） algorithm

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Graphics Processor Unit （GPU） acceleration of Time-Domain ...

2009 3rd IEEE International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless Communications

作者： Liu Kun Electronic engineering college chengdu university of information {5. chengdu china

A new accelerated method for Time-Domain Finite Element Method （TD-FEM） is presented. As the number of triangular elements mount up, compare with a Central Processing Unit （CPU） of comparable technology generation, the speed of Graphics Processor Unit （GPU） is faster and faster. Its properties make the off-the-shelf GPU suitable for accelerating TD-FEM simulations.

关键词： Graphics Processor Unit (GPU) Time- Domain Finite Element Method (TD-FEM)

来源： cnki会议评论

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惰性气体输运性质的理论计算

物理学报 2002年第3期51卷 497-500页

作者：郭建军四川工业学院电子信息与电气工程系成都610039

利用惰性气体原子间相互作用势 ,系统计算了 5.惰性气体的输运系数 ,包括第二维里系数B、扩散系数D、热传导系数λ、黏滞系数 η和热扩散因子αT 的计算 .从输运性质的计算证明了Tang Toennies势模型的准确性 .

关键词：惰性气体 Tang-Toennies势模型输运系数理论计算输运性质扩散系数

Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong Physics Department, college of information Science and engineering, Ocean university of china, Qingdao 266100, Shandong, china [a] Physics Department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5.meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3P, TIP4P, MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4P, and TIP3P potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

Particle swarm optimization with a leader and followers

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Progress in Natural Science:Materials International 2008年第11期18卷 1437-1443页

作者： Junwei Wang Dingwei Wang Institute of Systems engineering,college of information Science and engineering,Northeastern university,Shenyang 110004,{5. Institute of Systems engineering College of Information Science and Engineering Northeastern University Shenyang 110004 China

Referring to the flight mechanism of wild goose flock,we propose a novel version of Particle Swarm Optimization(PSO)with a leader and *** is referred to as Goose Team Optimization(GTO).The basic features of goose team flight such as goose role division, parallel principle,aggregate principle and separate principle are implemented in the recommended *** GTO,a team is formed by the particles with a leader and some *** role of the leader is to determine the search *** followers decide their flying modes according to their distances to the leader ***,a wide area can be explored and the particle collision can be really *** GTO is applied to four benchmark examples of complex nonlinear functions,it has a better computation perfor- mance than the standard PSO.

关键词： Particle swarm optimization Goose team optimization Role division Parallel principle Aggregate principle Separate principle