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Science China(Technological Sciences) 2010年第12期53卷 3264-3274页

作者： XU Meng1 & GAO ZiYou2 1 MOE Key Laboratory for Urban Transportation Complex Systems Theory and technology, beijing Jiaotong University, beijing 100044, China 2 institute of Systems Science, School of Traffic and Transportation, beijing Jiaotong University, beijing 100044, China MOE Key Laboratory for Urban Transportation Complex Systems Theory and technology Beijing Jiaotong University Beijing China institute of Systems Science School of Traffic and Transportation Beijing Jiaotong University Beijing China

This paper is concerned with the algorithm of the supply chain network equilibrium model and its equivalent supernetwork based traffic network equilibrium model with elastic demands. Both models are further written as nonlinear complementarity problems. Semismooth least squares reformulations of the complementarity problems are presented and their convergence properties are investigated. Considering the drawbacks of Quasi-Newton method (using the Fischer-Burmeister function), a semi-smooth Levenberg-Marquardt-type method is proposed to solve the problems. Numerical examples show that the Levenberg-Marquardt-type method can solve the supply chain network equilibrium model and its equivalent supernetwork based traffic network equilibrium model significantly, and is more efficient than the Quasi Newton method and the modified projection method. Furthermore, the Levenberg-Marquardt-type method with the equivalent supernetwork based complementarity formulation can be implemented faster than with the supply chain network equilibrium complementarity formulation.

关键词： supply chain networks traffic network equilibrium supernetwork nonlinear complementarity problem Levenberg Marquardt-type method

Final Temperature Prediction Model of Molten Steel in RH-TOP Refining Process for IF Steel Production

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Journal of Iron and Steel Research International 2012年第3期19卷 1-5页

作者： WANG Yu-nan1, BAO Yan-ping1, CUI Heng2, CHEN Bin3, JI Chen-xi3 (1. State Key Laboratory of Advanced Metallurgy, University of Science and technology beijing, beijing 100083, China 2. Engineering Research institute, University of Science and technology beijing, beijing 100083, China 3. Shougang Research institute of technology, beijing 100041, China) State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing China Engineering Research institute University of Science and Technology Beijing Beijing China Shougang Research institute of technology Beijing China

In order to precisely control the final temperature of molten steel in RH （Ruhrstahl Heraeus）-TOP blowing refining, the final temperature prediction models of molten steel in RH-TOP blowing refining process for Interstitial Free （IF） steel production were established under the condition of oxygen blowing and non-oxygen blowing respec- tively. The results show that the beginning molten steel temperature of refining and the amount of added scrap were influential factors, the baking temperature in vacuum chamber was a factor that had small influence. When the model was operated, the hitting probability was above 95%（under the condition of both oxygen blowing and non-oxygen blo- wing） of prediction deviation ±10℃. The accuracy is analyzed.

关键词： RH-TOP molten steel temperature prediction model

Alpha-latrotoxin Triggers Extracellular Ca2+-dependent Exocytosis and Sensitizes Fusion Machinery in Endocrine Cells

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 8-14页

作者： Zhi-Tao HU~(1#),Ping ZHAO~(1#),Jie LIU~(1#),Zheng-Xing WU~(1*),and Tao XU~(1,2*) ~1 School of Life Science and technology,Huazhong University of Science and technology,Wuhan 430074,China ~2 National Laboratory of Biomacromolecules,institute of Biophysics,Chinese Academy of Sciences,beijing 100101,China School of Life Science and technology Huazhong University of Science and Technology Wuhan 430074 China National Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China

α-Latrotoxin from the venom of black widow spider induces and augments neurotransmitterand hormone release by way of extracellular Ca2+influx and cellular signal transduction *** usingwhole cell current and capacitance recording,the photolysis of card Ca2+,and Ca2+microfluorometry andamperometry,we investigated the stimulating effect and mechá（?）ism of α-latrotoxin on exocytosis in ratpancreatic β cells,LβT2 cells and latrophilin plasmid-transfected INS-1 *** data indicated that:（1）α-latrotoxin increased cytosolic Ca2+concentration through the formation of cation-permitting pores and sub-sequent Ca2+influx with the presence of extracellular Ca2+;（2）α-latrotoxin stimulated exocytosis in normalbath solution and its stimulating effect on secretion was eradicated in Ca2+-free bath solution; and （3）α-latrotoxin sensitized the molecular machinery of fusion through activation of protein kinase C and increasedthe response of cells to Ca2+photolysed by a flash of ultraviolet *** summary,α-latrotoxin inducedexocytosis by way of Ca2+influx and accelerated vesicle fusion by the sensitization of fusion machinery.

关键词： α-latrotoxin exocytosis calcium Ca2+-sensitivity of fusion protein kinase C(PKC) capacitance measurement amperometry

Security Research on Engineering Database System

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厦门大学学报（自然科学版） 2002年第S1期41卷 288-289页

作者： REN Jian-ping 1,2, SONG Han-tao 2, LIANG Yun-rong 2 (1. North China institute of technology, Taiyuan 030051, China 2. beijing institute of technology, beijing 100081, China)

Engine engineering database system is an oriented C AD applied database management system that has the capability managing distributed data. The paper discusses the security issue of the engine engineering database management system (EDBMS). Through studying and analyzing the database security, to draw a series of securi ty rules, which reach B1, level security standard. Which includes discretionary access control (DAC), mandatory access control (MAC) and audit. The EDBMS implem ents functions of DAC, MAC and multigranularity audit. DAC solves the problems o f role inheritance, right contain, authorization identify and cascade revoke, et c; MAC includes subject and object security setup rule, security modify rule and multilevel relation access operation rule, etc; Audit allows making the sub ject, object or operation type as different audit object to implement flexible a nd multigranularity audit method. The model is designed act as a security agent to access daemon database. At present, the model is implemented which runs on th e Windows 2000 environments.

关键词： engineering database management system (EDBMS) s ecurity agent security level

Numerical and experimental investigation of the fracture behavior of shock loaded alumina

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Science China(Physics,Mechanics & Astronomy) 2010年第2期53卷 244-252页

作者： REN HuiLan1,SHU XueFeng2 & LI Ping3 1 State Key Laboratory of Explosion Science and technology,beijing institute of technology,beijing 100081,China 2 institute of Applied Mechanics and Biomedical Engineering,Taiyuan University of technology,Taiyuan 030024,China 3 Labroratory for Shock Wave and Detonation Physics Research,institute of Fluid Physics,CAEP,Mianyang 610059,China State Key Laboratory of Explosion Science and technology Beijing Institute of Technology Beijing China institute of Applied Mechanics and Biomedical Engineering Taiyuan University of Technology Taiyuan China Labroratory for Shock Wave and Detonation Physics Research Institute of Fluid Physics CAEP Mianyang China

Plate impact expeiments are conducted to investigate the dynamic behavior of alumina by using one stage light gas gun. A ve-locity interferometer system for reflectors (VISAR) is used to obtain Hugoniot elastic limit and the free surface velocity profile,which consists of an elastic wave followed immediately by a dispersive inelastic wave. The stress histories under different impact velocities are measured by in-material manganin gauges. Based on the experimental data a Hugoniot curve is fitted,which shows the compressive characteristics that alumina changes typically from elastic to "plastic" ,and under higher pressure it will be transferred to similar-fluid state. The turning point of the Hugoniot curve from a high pressure region to a low pressure region is about 11.4 GPa. The fracture process of alumina is simulated by way of finite element code. After the analysis of the fracture mechanism,the numerical results show an important role played by the nucleation and the growth of the cracks in the macro-scopic fracture of the alumina target. The numerical predictions of stress histories are compared with the experimental results,which indicates consistency between them.

关键词： plate impact experiment hugoniot curve fracture characteristics numerical simulation

Transcription Factors Ets2 and Sp1 Act Synergistically with Histone Acetyltrans-ferase p300 in Activating Human Interleukin-12 p40 Promoter

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Acta Biochimica et Biophysica Sinica 2006年第3期38卷 194-200页

作者： Hai-jing SUN~(1,2) Xin XU~1 Xiu-Li WANG~1 Liang WEI~1 Fen LI~1 Jun LU~1* Bai-Qu HUANG~11 institute of Genetics and Cytology,Northeast Normal University,Changchun 130024,China2 beijing Normal University,beijing 100875,China institute of Genetics and Cytology Northeast Normal UniversityChangchun 130024 China beijing Normal University Beijing 100875 China

There has been considerable interest in researching the regulatory mechanisms that control thesynthesis of interleukin （IL）-12,which plays a central role in the differentiation of T-helper-1 *** thisstudy,we performed a series of transient transfection experiments designed to elucidate the functional rela-tionship between the IL-12 promoter-specific transcription factors （Ets2 and Sp1） and histone acetylationmodification in IL-12 regulation mediated by p300 and various histone deacetylases （HDACs）.Results pre-sented in this report demonstrated that the transcription factors Ets2 and Sp1 acted synergistically with p300to activate the human IL-12 *** histone acetyltransferase （HAT） activity of p300 was required forthis synergic effect,because the adenovirus E1A protein inhibited the ***,HDACs re-pressed the synergic effect of transcription factors and histone acetylation on the activation of IL-12,whilep300 was able to rectify *** data indicated that Ets2 and Sp1 worked concertedly and synergisticallywith p300 in the regulation of human IL-12 expression.

关键词： Ets2 Sp1 histone acetyltransferase p300 interleukin-12

Microstructure and Texture Characterization in Nd:YAG Laser Welds of 5A90 Aluminum-Lithium Alloys

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稀有金属材料与工程 2011年第S4期40卷 39-43页

作者： Cui Li1,Li Xiaoyan1,He Dingyong1,Chen Li2,Gong Shuili21College of Materials Science and Engineering,beijing University of technology,beijing 100124,China2Science and technology on Power Beam Processes Laboratory,beijing Aeronautical Manufacturing technology Research institute,beijing 100024,China beijing Univ Technol Coll Mat Sci & Engn Beijing 100124 Peoples R China beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

Microstructure and texture characterization in Nd:YAG laser welds of 5A90 Aluminum-Lithium (Al-Li) alloys were studied by means of optical microscope (OM),electron back scattered diffraction (EBSD) and transmission electron microscope (TEM).The solidification structure,misorientation angle,dislocation density and microtexture of the welds in 5A90 Al-Li alloys were investigated and compared with the unaffected base *** results show that microstructure and texture changes of the 5A90 Al-Li alloy after laser *** solidification structure results show that a zone of equiaxed grains (EQZ) along the fusion boundary is formed and the weld metal exhibits entirely equiaxed dendritic grains for 5A90 Al-Li *** study clearly shows the high angle boundaries (>15°) and microtexture changes for 5A90 Al-Li alloy after laser *** images indicate that the laser welding has no influence on the dislocation density.

关键词： laser welding Al-Li alloy microstructure texture EBSD

Influencing Factors on Center Segregation in Continuously Cast Pipeline Steel Slabs

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Journal of Iron and Steel Research International 2011年第S2期18卷 352-357页

作者： LIU Yang1, WANG Xin-hua2, WANG Wen-jun1, JIANG Zhong-hang1 (1.Shougang Research institute of technology beijing 100043 china 2.University of Science and technology beijing 100083, China) Shougang Res Inst Technol beijing Beijing 100043 Peoples R China Univ Sci & Technol beijing Beijing 100083 Peoples R China

The factors which influence center segregation of continuously cast slabs are obtained through analyzing the database of macrostructrue. It indicates that center segregation becomes severer with the increasing content of carbon, phosphorus and sulfur; Center segregation will be reduced obviously if the content of manganese is higher than 1.5% and the ratio of Mn/S is higher than 300; High degree of superheat , high casting speed and increasing width of slabs will increase the degree of center segregation. Since center segregation below class B has little effect on the property of steel, hence, in order to low the ratio of center segregation of class B-1.0 down to 10%, several control strategies are presented as follows: the contents of carbon, phosphorus and sulfur must be focalized in lower range of steel grade demanded, but manganese upper operating range control. The referenced contents of the elements in molten steel are required like this: [C]1%,[S]1.5%,[Mn]/[S]>300; The degree of superheat should be lower than 24℃ and the casting speed should be defined to 1.0-1.1 m·min-1. At the same time, proper secondary cooling system of water distribution should be developed and the precision of continuous caster should be also improved.

关键词： continuous casting slab, center segregation, microalloy steel

Application of asymptotic waveform approximation technique to hybrid FE/BI method for 3D scattering

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Science in China(Series F) 2007年第1期50卷 124-134页

作者： PENG Zhen1,2,3 & SHENG XinQing2 1 institute of Electronics, Chinese Academy of Sciences, beijing 100080, China 2 Department of Electronic Engineering, beijing institute of technology, beijing 100081, China 3 Graduated University of Chinese Academy of Sciences, beijing 100039, China institute of Electronics Chinese Academy of Sciences Beijing China Department of Electronic Engineering Beijing Institute of Technology Beijing China Graduated University of Chinese Academy of Sciences Beijing China

The asymptotic waveform evaluation （AWE） technique is a rational function approximation method in computational mathemetics, which is used in many appllcations in computational electromagnetlca. In this paper, the performance of the AWE technique in conjunction with hybrid finite element/boundary integral （FE/BI） method is firstly Inveetlgeted. The formuletlon of the AWE applied in hybrid FE/BI method is given in detail. The characteristic implementation of the application of the AWE to the hybrid FE/BI method is discussed. Numarlcel results demonstrate that the AWE technique can greatly speed up the hybrid FE/BI method to acquire wide-band and wide-angle backecatter radar-cross-section （RCS） by complex targets.

关键词： hybrid FE/BI AWE electromagnetic scattering RCS

On the TOPS mode spaceborne SAR

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Science China(Information Sciences) 2010年第2期53卷 367-378页

作者： BAI Xia 1 , SUN JinPing 2 , HONG Wen 3 & MAO ShiYi 2 1 Department of Electronic Engineering, beijing institute of technology, beijing 100081, China 2 Department of Electronic Engineering, Beihang University , beijing 100191, China 3 institute of Electronics,Chinese Academy of Sciences, beijing 100190, China Department of Electronic Engineering Beijing Institute of Technology Beijing China Department of Electronic Engineering Beihang University Beijing China institute of Electronics Chinese Academy of Sciences Beijing China

TOPS (terrain observation by progressive scans) is a recently proposed SAR mode for wide swath acquisition, which aims at achieving the same coverage and resolution as the SCAN mode besides creating scalloping-free images. In this paper, a general SAR imaging model used in TOPS and other SAR modes is introduced, where the antenna sweep rate, Doppler centroid rate, illumination time and azimuth resolution are described by a parameter defined as the "mode factor". After analyzing the characteristics of TOPS signal, an algorithm based on chirp-z transform is proposed, in which a new de-rotation function is used. Simulation results validate the proposed algorithm.

关键词： synthetic aperture radar acquisition mode TOPS