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PRIMAL PERTURBATION SIMPLEX ALGORITHMS FOR LINEAR PROGRAMMING

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Journal of Computational Mathematics 2000年第6期18卷 587-596页

作者： Ping-qi Pan (Department of Applied Mathematics, Southeast university, Nanjing 210096, china.) 东南大学江苏南京 210096

In this paper, we propose two new perturbation simplex variants. Solving linear programming problems without introducing artificial variables, each of the two uses the dual pivot rule to achieve primal feasibility, and then the primal pivot rule to achieve optimality. The second algorithm, a modification of the first, is designed to handle highly degenerate problems more efficiently. Some interesting results concerning merit of the perturbation are established. Numerical results from preliminary tests are also reported. [ABSTRACT FROM AUTHOR]

关键词： linear programming perturbation primal simplex algorithm partially revised tableau

A Case Study of 3D Protein Structure Prediction with Genetic Algorithm and Tabu Search

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Wuhan university Journal of Natural Sciences 2011年第2期16卷 125-129页

作者： WANG Ting1,2, ZHANG Xiaolong1, 3 1. School of Computer Science and Technology, Wuhan university of Science and Technology, Wuhan 430065, Hubei, china 2. College of Mobile Telecommunications, Chongqing university of Posts and Telecommunications, Chongqing 400065, china 3. State Key Laboratory of Bioelectronics, Southeast university, Nanjing 210096, china School of Computer Science and Technology Wuhan University of Science and Technology Wuhan Hubei China College of Mobile Telecommunications Chongqing University of Posts and Telecommunications Chongqing China State Key Laboratory of Bioelectronics Southeast University Nanjing China

This paper describes a case study of 3D protein structure prediction of six sequences from protein data bank （PDB） by genetic algorithm and tabu search （GATS）, where off-lattice AB model is considered as a simplified model of protein structure. The lowest-energy values required for forming the native conformation of proteins are searched by GATS, and then the coarse structures （i.e., simplified structure） of the proteins are obtained according to the multiple angle parameters corresponding to the lowest energies. All the coarse structures form single hydrophobic cores surrounded by hydrophilic residues, which stay on the right side of the actual characteristic of protein structure. It demonstrates that this approach can predict the 3D protein structure effectively.

关键词： 3D protein structure off-lattice AB model genetic algorithm and tabu search (GATS)

Capacity analysis and optimal power allocation for coordinated transmission in MIMO-OFDM systems

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Science china(Information Sciences) 2012年第6期55卷 1372-1387页

作者： CUI QiMei 1,HUANG XueQing 1,LUO Bing 1,TAO XiaoFeng 1 & JIANG Jun 2 1 Key Laborary of Universal Wireless Communications,Beijing university of Posts and Telecommunications,Beijing 100876,china 2 StarPoint Communication Software Company Ltd.,Beijing 100102,china 1. Key Laborary of Universal Wireless Communications Beijing University of Posts and Telecommunications Beijing 100876 China2. StarPoint Communication Software Company Ltd. Beijing 100102 China

Coordinated transmission in multicell coordination networks has attracted much attentions in recent *** the paper,we investigate one open problem in the above area,which is concerned with how to solve the closed-form optimal power allocation scheme of coordinated transmission in downlink orthogonal frequency-division multiplexing (OFDM) systems with multiple antenna configurations and individual power constraints.A frequency-selective fading multiple-input multiple-output (MIMO) channel is *** derive the closed-form solutions of sum-rate capacity and optimal power allocations for coordinated transmission under the diversity case and the multiplexing case by solving the constrained optimization *** simulations are performed to verify the derived theoretical conclusions by means of comparing the proposed optimal power allocation (OPA) scheme with the other two typical power allocation *** is the power allocation scheme combining traditional water-filling with equal power (WS-EF PA).The other is equal power allocation (EPA) scheme.

关键词： coordinated multi-point transmission multicell cooperation capacity analysis MIMO-OFDM power allocation frequency selective MIMO channel

CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials physics,university of Science and Technology Beijing,Beijing 100083,china

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of Science and Technology Beijing,Beijing,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North china Craton

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矿物学报 2009年第S1期29卷 113-114页

作者： BI Shi-jian1,2,LI Jian-wei1,2,LI Zhan-ke1,2,ZHANG Su-xin1,ZHENG Shu1(1. State Key Laboratory of Geological Processes and Mineral Resources,china university of Geosciences,430074 Wuhan,china 2. Faculty of Earth Resources,china university of Geosciences,430074 Wuhan,china)

Gold is commonly associated with arsenic in As-rich pyrite or arsenopyrite in a variety types of gold deposit,such as sediment-hosted gold deposits,epithermal Au-Ag deposits,Au-rich VMS deposits,and mesothermal lode g... 详细信息

关键词： Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North china

The characteristics of sea fog with different airflow over the Huanghai Sea in boreal spring

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Acta Oceanologica Sinica 2010年第4期29卷 3-12页

作者： HUANG Jian WANG Xin ZHOU Wen HUANG Huijun WANG Dongxiao ZHOU Faxiu Institute of Tropical and Marine Meteorology China Meteorological Administration Guangzhou 510080 China Guy Carpenter Asia-Pacific Climate Impact Centre School of Energy and Environment City University of Hong Kong Hong Kong China CAS key laboratory of tropical marine environmental dynamics South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Department of meteorology Ocean University of China Qingdao 262003 China

Using the observations from ICOADS datasets and contemporaneous NCEP/NCAR reanalysis datasets during 1960-2002,the study classifies the airflows in favor of sea fog over the Huanghai （Yellow） Sea in boreal spring （April-May） with the method of trajectory analysis,and analyzes the changes of proportions of warm and cold sea fogs along different paths of *** to the heat balance equation,we investigate the relationships between the marine meteorological conditions and the proportion of warm and cold sea fog along different airflow *** major results are summarized as follows.（1） Sea fogs over the Huanghai Sea in spring are not only warm fog but also cold *** proportion of warm fog only accounts for 44% in April,while increases as high as 57% in May.（2） Four primary airflow paths leading to spring sea fog are *** are originated from the northwest,east,southeast and southwest of the Huanghai Sea,*** occurrence ratios of the warm sea fog along the east and southeast airflow paths are high of 55% and 70%,while these along the southwest and northwest airflow paths are merely 17.9% and 50%.（3） The key physical processes governing the warm/cold sea fog are heat advection transport,longwave radiation cooling at fog top,solar shortwave warming and latent heat flux between airsea interfaces.（4） The characteristics of sea fog along the four airflow paths relate closely to the conditions of water vapor advection,and the vertical distribution of relative humidity.

关键词： spring sea fog over the Huanghai Sea airflow paths water vapor flux heat advection vertical distribution of water vapor

THE ANALYSIS METHODOLOGY OF POLLEN FROM THE MESOZOIC—CENOZOIC RED BEDS IN NORTHERN TIBET

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地学前缘 2000年第S1期7卷 186-187页

作者： WT5,5”BZ]Wei Mingjian 1, Wan Xiaoqiao 2, Wang Chengshan 3, Yin Haisheng 3(1.Capital Normal university, Beijing 100037,china 2.china university of Geosciences, Beijing 100083,china 3.Chengdu Institute of Technology, Chengdu 610059,china)

A group of red interbedded sandstone, siltstone and clay\|stone occur in the inland of northern Tibet. During the last 50 years, a lot of researches have been done at this group of beds along the Qinghai\|Xizang highway in the Kekexili area.. According to the lithological characters, the strata have been divided into tow parts, the lower part named as the Feng huoshan group, and the upper part the Yaxicuo group. It is obscure to the age of the strata. For example, Yi jixiang et al. (1990) put them in early Pliocene in the light of the microfossils which they found at the foot of Feng huoshan mountain. The fossils include (1) Charophyta: Rhabdochara? sp ., Peckichara subsphecrica?, Cyrogoniae; (2) Ostracoda: Cypris sp .; (3) Gastropod: Sinoplanorbis sp ., Amnicola sp ., Bithynia sp .; and (4) Sporopollen: Tricoporopollenites nactonodus ?, Polypodiceoisporites, Cyathidites, Schizosporis, Pediastrum. Based on different species of Charophyta, Ostracoda, Gastropod, Bivalve, Sporopollen, Zhang Yifu et al. (1994) refer the strata to Cretaceous. The lower abundance of the fossils from previous research gave lower precision of fossil identification. Thus, the age of the strata was confusion.

关键词： inland of Tibet Cenozoic red beds Pollen analysis method ology

Controlled Deposition of HAp Mimicking Tooth Enamel

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Journal of Wuhan university of Technology(Materials Science) 2005年第B12期20卷 153-155页

作者：黄微雅张渊明 Department of Chemistry Jinan University Guangzhou 510632 China

Chemical compositions and mierosturcture of mature human tooth enamel were investigated by XRD , FTIR and SEM to further understand the characteristics of tooth enamel. In order to obtain apatite crystals chemically and structurally similar to those in tooth enamel, biomimetic way was employed. Self-assembled monolyers terminated with-SO3 H groups were used as deposition substrates and 1.5 SBF （ the concentrations of Ca^2＋ and PO4^3- ions 1.5 times ttum those in simulated body fluid ） with and without 5 ppm F^- were used as soaking medium. The XRD and FTIR results showed that both the deposited fluoride-substituted hydroxyapatite （ F-HAp ） crystals in 1.5 SBF with F^- and hydroxyapatite （ HAp ） crystals in 1.5 SBF were carbonate-contain ing, mimicking human tooth enamel in chemical compositions. The SEM photos showed that needle-like F-HAp crystals had large aspect ratios and grew in bundles, which were similar to the crystals in human tooth enomel. The results provide available information on dental restoration.

关键词： tooth enamel biomimetic self assembled monolyers simulated body fluid hydroxyapatite

On the Existence of (v,3×3,λ)-Splitting Balanced Incomplete Block Design with λ between 2 to 9

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Journal of Shanghai Jiaotong university(Science) 2008年第4期13卷 482-486页

作者：苏仁旺王金华 College of Statistics and Mathematics Zhejiang Gongshang University School of Science Nantong University

Let （v, u × c,λ）-splitting BIBD denote a （v, u × c,λ）-splitting balanced incomplete block design of order v with block size u × c and index A. The necessary conditions for the existence of a （v, u × c,λ）-splitting BIBD are v ≥ uc, λ（v- 1） -- 0 0 mod （c（u- 1）） and Av（v- 1） - 0 mod （c^2u（u- 1））. In this paper, for 2 ≤λ≤ 9 the necessary conditions for the existence of a （v, 3 × 3, λ）-splitting BIBD are also sufficient with one possible exception for （v, λ） = （39, 9）.

关键词： Splitting balanced incomplete block design group-divisible design (GDD)