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Local segment-shared protection based on source egress gateway selection for multi-domain optical mesh networks

Science china(Information Sciences) 2011年第2期54卷 227-235页

作者： ZHANG ShengFeng1,3, PENG YunFeng1,2. DU Shu1, YANG XiaoLong1,2.& LONG KePing1,2.1Research center for Optical Internet and Mobile Information networks, {2. of Electronic Science and Technology of china, Chengdu 6.1731, china 2.nstitute of Advanced network Technology and New Serives (ANTS), {2. of Science and Technology Beijing, Beijing 100083, china 3Research center for Optical Internet networks, Chongqing {2. of Posts and Telecommunications, Chongqing 40006., china 1. Research center for Optical Internet and Mobile Information networks University of Electronic Science and Technology of China Chengdu 611731 China3. Research Center for Optical Internet Networks Chongqing University of Posts and Telecommunications Chongqing 400065 China2. Institute of Advanced Network Technology and New Serives (ANTS) University of Science and Technology Beijing Beijing 100083 China

Survivability for multi-domain optical networks is becoming a key parameter due to expanding network. In order to provide the shared-path-protected lightpath in multi-domain optical mesh networks, we propose a protection solution, called GSLSSP. A new source egress gateway selecting mechanism is adopted in this solution. For each connection request, this mechanism can enable the source node to select a better egress gateway node to the destination domain and compute one inter-domain working path near the optimal path with the cooperating of this gateway node, under scalability and domain privacy constraint of multi-domain networks. And then one intra-domain link-disjoint local segment-backup path for each working-segment path is computed out in each single-domain passed by the working path. Simulation evaluation shows that the proposed scheme can provide 100% protection ability for multiple failures. Besides, it is effective in multi-domain path protection with more efficient resource utilization, lower blocking probabilities and less inter-domain cost than other schemes.

关键词： survivability optical mesh networks multi-domains multiple failures segment-shared protection

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A theoretical analysis on efficiency of some Newton-PCG methods

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Science china Mathematics 2005年第8期48卷 1046-1064页

作者： DENG Naiyang, ZHANG Jianzhong & ZHONG Ping china agricultural university, Beijing 100083, china City {2. of Hong Kong, Hong Kong, china 1. china agricultural university 100083 Beijing China 2. City university of Hong Kong Hong Kong China

In this paper, we study the efficiency issue of inexact Newton-type methods for smooth unconstrained optimization problems under standard assumptions from theoretical point of view by discussing a concrete Newton-PCG algorithm. In order to compare the algorithm with Newton's method, a ratio between the measures of their approximate efficiencies is investigated. Under mild conditions, it is shown that first, this ratio is larger than 1, which implies that the Newton-PCG algorithm is more efficient than Newton's method, and second, this ratio increases when the dimension n of the problem increases and tends to infinity at least at a rate In n/In 2.when n→∞, which implies that in theory the Newton-PCG algorithm is much more efficient for middle- and large-scale problems. These theoretical results are also supported by our preliminary numerical experiments.

关键词： unconstrained optimization, Newton's method, preconditioned conjugate gradient method, efficiency.

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National 2.00' GPS control network of china

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Progress in Natural Science:Materials International 2007年第8期17卷 983-987页

作者： Yang Yuanxi~(1**) Tang Yingzhe~1 Chen Chuanlu~2.Wang Min~3 Zhang Peng~4 Wang Xiaorui~2.Song Lijie~5 Zhang Zusheng~6.(1.Xi'an Research Institute of Surveying and Mapping,Xi'an 710054,china 2.Geodetic Data Processing {2.,Xi'an 710054,china 3.{2. of Earthquake Analysis and Prediction,china Seismological Bureau,Beijing 100036.china 4.National Geomatics {2. of china,Beijing 100044,china 5.Institute of Surveying and Mapping,Zhengzhou university of Information Engineering,Zhengzhou 450052.china 6.First Crustal Deformation Monitoring {2.,china Seismological Bureau,Tianjin 300180,china) [a]Xi' an Research Institute of Surveying and Mapping Xi' an China [b]Geodetic Data Processing center Xi'an China [c]center of Earthquake Analysis and Prediction China Seismological Bureau Beijing China [d]National Geomatics center of Chinna Beijing China [e]Institute of Surveying and Mapping Zhengzhou University of Information Engineering Zhengzhou China [f]First Crustal Deformation Monitoring center China Seimological Bureau Tianjin China

An accurately unified national GPS network with more than 2.00 stations,named"National 2.00' GPS Control Net- work",signed the epoch 2.00.0,has been established by integrating the existing six nationwide GPS networks of{2. set up by differ- ent departments with different *** paper presents the characteristics of the existing GPS networks,summarizes the strategies in the integrated adjustment of the GPS network,including functional model,stochastic model as well as the adjustment principle modifi- *** modifying the adjustment strategies according to the characteristics of the existing GPS networks and under the support of the IGS stations,the accuracy of the integrated national GPS network is greatly *** datum differences among the sub networks disappear,the systematic error influences are weakened,and the effects of the outliers on the estimated coordinates and their variances are *** is shown that the average standard deviation for the horizontal component is smaller than 1.0 cm,the vertical component is smaller than 2.0 cm,and the three-dimensional (3-D) position of geocenter coordinates is smaller than 3.0 *** exterior checking ac- curacy for the 3-D position is averagely better than 1.0 cm.

关键词： GPS control network adjustment systematic errors robust estimation variance component estimation coordinate system

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Simultaneously inducing synthesis of semiconductor selenium multi-armed nanorods and nanobars through bio-membrane bi-templates

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Science china Chemistry 2004年第6期47卷 507-511页

作者： LI Li1, WU Qingsheng1 DING Yaping2.& LI Ping3 1. Department of Chemistry, Tongji university, Shanghai 2.0092. china 2. Department of Chemistry, Shanghai university, Shanghai 2.0436. china 3. Department of Food, Anhui agricultural university, Hefei 2.0036. china 1. Department of Chemistry Tongji University 200092 Shanghai China 2. Department of Chemistry Shanghai University 200436 Shanghai China 3. Department of Food Anhui Agricultural University 230036 Hefei China

Multi-armed nanorods and nanobars of semiconductor selenium were simultane- ously synthesized in the light of biomineralization process through bio-membrane bi-templates of rush at room temperature. The multi-armed nanorods are 6. nm in diameter and 1.5 μm in length; the nanobars are 150 nm in diameter and 1000—1100 nm in length. The XRD pattern indicates that these nanocrystals were crystallized in the hexagonal structure with lattice constants a = 0.437 nm, c = 0.495 nm. The possible formation mechanism was investigated.

关键词： selenium, multi-armed nanorods, nanobars, bio-membrane, bi-templates.

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Electrochemical Characterization of Surface-modified LiMn_2._4 Cathode Materials for Li-ion Batteries

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Journal of Wuhan university of Technology(Materials Science) 2006年第4期21卷 56-59页

作者：禹筱元 College of Science South China Agricultural University Guangzhou 510642ChinaSchool of Physics & Engineering Sun Yat-sen University Guangzhou 510275China

To improve the performance, the surface of 12.n2.4 was coated with very fine MgO , Al2.3 and ZnO by solgel method, respectively. The structure and morphology of the coated materials were investigated by X-ray diffraction （ XRD ）, X-ray photoelectron spectroscopy （ XPS ） and scanning electron microscopy （SEM）. The charge and discharge performance of uncoated and surfnce modified 12.n2.4 spinel at 2.℃ and 55 ℃ were tested, using a voltage window of 3.0-4.35 V and a current deasity of 0. 1 C rate. There is a slight decrease in the initial discharge capacity relative to that of uncoated UMn2.O4, bat the cycle ability of 12.12.n2.4 coated by metal-oxide has remarkably been improved. The EIS measuremeuts of uncoated and Al2.3 -coated 12.n2.4 were carried out by a model 2.3 A potentiostatl galvanistat controUed by a computer using M2.0 software, and using a freqnency response analyzer （ Zsimpwin ） combined with a potentiostate （ PAR 2.3）. Coaseqnently, the reason for the improved cycle properties is that the surface modification reduces the dissolution of Mn , which results from the suppression of the electrolyte decomposition, and suppresses the formation of passivation film that acts as an electronic insulating layer. In conclusion, the use of surface modification is an effective way to improve the electrochemical performance of 12.n2.4 cathode material for lithium batteries.

关键词： lithium-ion batteries surface modification metal-oxide coating: 12.n2.4 cathode

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Mechanisms of invasive population establishment and spread of pinewood nematodes in china

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Science china(Life Sciences) 2009年第6期52卷 587-594页

作者： XIE BingYan1,CHENG XinYue2.SHI Juan3,ZHANG QingWen4,DAI ShuMing1,CHENG Fei Xue2.& LUO YouQing3 1 Institute of Vegetables and Flowers,Chinese Academy of agricultural Sciences,Beijing 100081,china 2.Beijing Normal {2.,Beijing 100875,china 3 Beijing Forestry {2.,Beijing 100083,china 4 Chinese agricultural {2.,Beijing 100094,china 1. Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 China 2. Beijing Normal university Beijing 100875 China 3. Beijing Forestry university Beijing 100083 China 4. Chinese agricultural university Beijing 100094 China

This paper summarizes the results of our study of the pinewood nematode(Bursaphelenchus xylophi-lus).By population genetic analysis,it was determined that there was no genetic bottle caused by the founder effect and genetic drift in the Chinese invasive *** invasions with large amounts of nematodes from different sources led to rich genetic diversity in the invasive *** high genetic diversity in the invasive process may be one of the genetic mechanisms in its successful *** testing interspecies competition,it was shown that,with high fecundity and a strong competitive ability,*** outcompeted the native species *** in the natural ecosystem during the invasion *** displacement may be one of the ecological mechanisms of ***'s *** addition,an unequal interspecific hybridization with intro-gress was in favor of the invasive species which also accelerated the replacement of *** by *** structures,functions and evolutions of a few important genes that are closely related to the ecological adaptation of pinewood nematodes were studied to explore the molecular mechanism of its ecological ***,the resistance and resilience mechanism of the pine ecosystem invaded by pinewood nematodes was also *** results of these studies uncovered a portion of the genetic and ecological mechanisms of PWN's successful invasion and laid a foundation for further study to obtain a comprehensive interpretation of the mechanisms of the nematode *** results also provided a scientific basis for effectively controlling the occurrence and spread of pine wilt disease which is caused by *** aspects requiring further investigation are considered.

关键词： pinewood nematode bioinvasion genetic diversity ecological adaptation resistance resilience

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Identification of one peptide which inhibited infectivity of avian infectious bronchitis virus in vitro

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Science china(Life Sciences) 2006年第2期49卷 158-163页

作者： PENG Bo1, CHEN Hanyang1, TAN Yadi1,2. JIN Meilin1,2. CHEN Huanchun1,2.& GUO Aizhen1,2.1. Laboratory of Animal Virology, College of Veterinary Medicine, Huazhong agricultural university, Wuhan 430070,{2. 2. National Key Laboratory of agricultural Microbiology, Huazhong agricultural university, Wuhan 430070,{2. 1. Laboratory of Animal Virology College of Veterinary Medicine Huazhong Agricultural University Wuhan 430070 China 2. National Key Laboratory of agricultural Microbiology Huazhong Agricultural University Wuhan 430070 China

Purified avian infectious bronchitis virus (IBV) was used to screen a random phage dis-play peptide library. After the fourth panning, 10 positive phages were sequenced and characterized. The phages specifically inhibited IBV infectivity in HeLa cells and blocked IBV haemagglutination. One linear peptide “GSH HRH VHS PFV” from the positive phages with the highest neutralization titer was synthesized and this peptide inhibited IBV infection in HeLa as well. The results may contribute to development of antiviral therapeutics for IBV and studying the determinants for viral and cell interac-tion.

关键词： avian infectious bronchitis virus, phage display, peptides.

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Factors governing formation of todorokite at atmospheric pressure

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Science china Earth Sciences 2005年第10期48卷 1678-1689页

作者： CUI Haojie1, FENG Xionghan1, LIU Fan1, TAN Wenfeng1 & HE Jizheng2.1. College of Resources and Environment, Huazhong agricultural university, Wuhan 430070,{2. 2. Research center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085,{2. College of Resources and Environment Huazhong agricultural university Wuhan{2. Research center for Eco-environmental Sciences Chinese Academy of Sciences Beijing china

Todorokite commonly occurs in Earth surface environments. The factors governing formation of todorokite, such as reaction temperature, metal ions, dissolved O2.and pH, were investigated in this paper. Results showed that the forming rate of todorokite and its crystallinity decreased with falling reaction temperature, and the effect of temperature was more significant than that of other parameters. Nature of metal ions in the interlayer of buserite precursor and the structure of the buserite precursor obviously affected buserite transformation into todorokite. Weak bonding between the metal ions and MnO6.layer of buserite was favorable to todorokite formation. The rate of todorokite formation was promoted at a lower temperature with appropriate bubbling of O2. The pH in the system slightly influenced the todorokite formation, and todorokite could also be formed in a weak alkali medium or in a slightly acidic medium. Aged buserite pre-cursor more easily form todorokite than the unaged one.

关键词： todorokite, buserite, manganese oxide mineral, atmospheric pressure, transformation.

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L-R smash products for bimodule algebras

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Progress in Natural Science:Materials International 2006年第6期16卷 580-587页

作者： ZHANG Liangyun (Department of Mathematics, Nanjing agricultural university, Nanjing 2.0095,{2. Department of Mathematics, Nanjing university, Nanjing 2.0008,{2.) [a] Department of Mathematics Nanjing Agricultural University Nanjing China [b] Department of Mathematics Nanjing University Nanjing China

In this paper, we prove that the L-R smash product A(?)H is exactly the twisted smash product A * H if H is a finite dimensional cocommutative Hopf algebra, and give a sufficient and necessary condition for L-R smash products to be bialgebras (Hopf algebras) . For any finite dimensional coquasitriangular Hopf algebra (H,σ), we prove that the L-R smash product H(?)H is semisimple Artinian if H is semisimple and H * is unimodular. In particular, the L-R smash product D(H)* (?)D(H)* semisimple Artinian if the Drin-fel'd double D(H) is semisimple.

关键词： bimodule algebras L-R smash products coquasitriangular Hopf algebras Long bialgebras.

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Application of Projection Pursuit Evaluation Model Based on Real-Coded Accelerating Genetic Algorithm in Evaluating Wetland Soil Quality Variations in the Sanjiang Plain, china

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Pedosphere 2003年第3期13卷 249-256页

作者： FUQIANG XIEYONGGANG WEIZIMIN Sichuanuniversity Chengdu610065(China) Heilongjianguniversity Harbin150080(China) Northeastagriculturaluniversity Harbin150030(China)

A new technique of dimension reduction named projection pursuit is applied to model and evaluatewetland soil quality variations in the Sanjiang Plain, Helongjiang Province, china. By adopting the im-proved real-coded accelerating genetic algorithm (RAGA), the projection direction is optimized and multi-dimensional indexes are converted into low-dimensional space. Classification of wetland soils and evaluationof wetland soil quality variations are realized by pursuing optimum projection direction and projection func-tion value. Therefore, by adopting this new method, any possible human interference can be avoided andsound results can be achieved in researching quality changes and classification of wetland soils.

关键词： evaluation projection pursuit evaluation model real-coded acceleratinggenetic algorithm soil quality variations

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