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Modulated Quasi-plane Tunneling Current

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 44-46页

作者： Peng Feng Wenmin Dai (china center of advanced {3. & technology (World Laboratory ) P.O. Box 873., Beijing 100080, china)(Applied {3. School, University of {3. and technology Beijing, Beijing 100083. china) china center of advanced {3. and technology (World Laboratory) P.O. Box 8730 Beijing 100080 China Applied science School University of Science and Technology Beijing Beijing 100083 China

A new tutmeling junction can be formed by an insulator layer inserting into a quantum well, and in the quantum well, a quasi-plane tunneling current can be formed by applying a tunneling voltage. If a P-N junction is grown on the quantum well, the tunneling current can be modulated by a P-N junction-bias voltage. The modulated quasi-plane tunneling current is not only related to the bias voltage, but also to the depth of the quantum well. It is analyzed that the P-N junction-bias voltage how to affect the tunneling current and a method of measuring the depth of the quantum well is presented.

关键词： quantum well tunneling current semiconductor device

Representations of Real and Complex Stability Radii of 2-Dimensional LinearSystems

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 299-301页

作者： Lequan Min1.2 Ning Song1(l Applied science School, University of science and technology’ Beijing, Beijing 100083.{3.2{3. center of advanced science and technology, Beijing 100080,{3.) Applied science School University of Science and Technology Beijing Beijing 100083 China china center of advanced {3. and technology Beijing 100080 China

Rigorous proofs are given for the representations of real and complex stability' radii of 2-dimensional linear systems. This representations can be used to analyze the robustness of a nominal 2-dimensional linear system under pelturbation of the system parameters, in particular testing the effect of numerical algorithms which are used to calculate the real stability radii of higher dimensional piecewise-linear systems.

关键词： linear systems robustness stability radii

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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science china(Physics,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3.4, JIANG YunGuo1 & LI XinGuo2,3.1 Institute of Theoretical Physics, College of Applied sciences, Beijing University of technology, Beijing 100022, china 2 Institute of Modern Physics, Chinese Academy of sciences, Lanzhou 73.000, china 3.center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Collisions, Chinese Academy of sciences, Lanzhou 73.000, china 4 china center of advanced science and technology (World Laboratory), Beijing 100080, china Institute of Theoretical Physics College of Applied Sciences Beijing University of Technology Beijing China center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou China china center of advanced {3. and technology (World Laboratory) Beijing China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Fluorescence dynamics of interactions between polyamide PyPyPyβDp and DNA

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science china Chemistry 2006年第1期49卷 75-80页

作者： ZHANG Huijuan1,2, WANG Jin3. WU Yishi1, YUAN Gu3. AI Xicheng1, WANG Li4 & ZHANG Jianping1 1. State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of sciences, Beijing 100080, china 2. School of Life science and technology, Beijing Institute of technology, Beijing 100081, china 3. College of Chemistry and Molecular Engineering, Peking University, Beijing 100080, china 4. center for Condensed Matter Physics, Institute of Physics, Chinese Academy of sciences, Beijing 100080, china Correspondence should be addressed to Ai Xicheng and Zhang Jianping State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China School of Life science and technology Beijing Institute of Technology Beijing China College of Chemistry and Molecular Engineering Peking University Beijing China center for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

The photophysical properties of the polyamide PyPyPyβDp (PPP) were investigated by means of steady-state absorption and fluorescence spectroscopies, as well as time-resolved fluo-rescence spectroscopy. It was found that the excited-state properties of PPP are very sensitive to solvents. In TKMC buffer PPP exhibited weak fluorescence with a decay time constant of 16 ps, while with the decrease of the solvent polarity PPP showed the blue-shifted peak position, increased inten-sity and lengthened life-time for its fluorescence behavior. In the presence of calf thymus DNA, it was observed that the fluorescence intensity was enhanced and the fluorescence lifetime increased from 16 to 3. ps for PPP, which verified that PPP bound into the minor groove of DNA duplex.

关键词： polyamide (PPP), calf thymus DNA (ctDNA), time-resolved fluorescence spectroscopy, recognition dynamics.

EMMA:An Efficient Massive Mapping Algorithm Using Improved Approximate Mapping Filtering

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Acta Biochimica et Biophysica Sinica 2006年第12期38卷 857-864页

作者： Xin ZHANG~1 Zhi-Wei CAO~2 Zhi-Xin LIN~3.Qing-Kang WANG~1* Yi-Xue LI~4 1 Institute of Micro/Nano science and technology,Shanghai Jiaotong University,Shanghai 20003.,china 2 Shanghai {3. for Bioinformation technology,Shanghai 20023.,china 3.College of Life science and technology,Shanghai Jiaotong University,Shanghai 20003.,china 4 Bioinformation {3. of Shanghai Institutes for Biological sciences,Chinese Academy of sciences,Shanghai 20003.,china Institute of Micro/Nano science and technology Shanghai Jiaotong UniversityShanghai 200030 China Shanghai center for Bioinformation technology Shanghai 200235 China College of Life science and technology Shanghai Jiaotong UniversityShanghai 200030 China Bioinformation center of Shanghai Institutes for Biological sciences Chinese Academy of SciencesShanghai 200031 China

Efficient massive mapping algorithm (EMMA),an algorithm on efficiently mapping massivecDNAs onto genomic sequences,has recently been *** process of mapping massive cDNAsonto genomic sequences has been improved using more approximate mapping filtering based on an enhancedsuffix array coupled with a pruned fast hash table,algorithms of block alignment extensions,and *** compared with the classical BLAT software in this field,the computing of EMMA ranges fromtwo to forty-one times faster under similar prediction precisions.

关键词： cDNA mapping maximal exact match enhanced suffix array pruned fast hash table extension algorithm

High-pressure synthesis and properties of CeO_2-ZrO_2 solid solution

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Chinese science Bulletin 2001年第10期46卷 801-806页

作者： XU Dapeng, WANG Quanyong, LU Zhe, LIU Zhiguo, ZHANG Gongmu & SU Wenhui1. Department of Physics, Jilin University, Changchun 13.023.0} 2. International center for Materials Physics, Chinese Academy of sciences, Shenyang 110015, china 3. center for Condensed Matter and Radiation Physics, china center of advanced science and technology (World Laboratory), Beijing 100080, china Department of Physics Jilin University Changchun China International center for Materials Physics Chinese Academy of Sciences Shenyang China center for Condensed Matter and Radiation Physics China Center of Advanced Science and Technology (World Laboratory) Beijing China

Using nanoparticles of CeO2 and ZrO2 prepared by the chemical precipitation method as starting materials, the single-phase cubic Ce0.5Zr0.5O2 solid solution (c-Ce0.5Z0.5O2) has been synthesized under 3.1 GPa at 1073.K for the first time. The structure of the c-Ce0.5Zr0.5O2 has not been changed before and after annealing at 773.K for 1 h. Only an unknown EPR signal (g =1.990) has been observed in the c-Ce0.5Zr0.5O2 and not varied after annealing at 773.K for 1 h, which exhibited that there exists no Ce3. in the c-Ce0.5Zr0.5O2 and the Ce4+ has not been reduced into Ce3. after annealing. The transport mechanism is ionic for the c-Ce0.5Zr0.5O2. The bulk conductivity (a =1.2×10-5 S/cm at 823.K, σ=2.1 ×10-3.S/cm at 1123.K) is the same as that of CeO2, but smaller than that of Y2O3.stabilized ZrO2. A marked curvature at T = 823.K has been observed in the Arrhenius plot of the bulk conductivity. The activation energy below 823.K is lower than that above 823.K, and the reason has been discussed.

关键词： CeO2-ZrO2 nanocrystalline high-pressure and -temperature solid-state reaction solid solution.

Modeling and verifying Web services driven by requirements:An ontology-based approach

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science in china(Series F) 2006年第6期49卷 792-820页

作者： HOU Lishan1,3.JIN ZHi1,2 & WU Budan1,4 1. Academy of Mathematics and Systems science, Chinese Academy of sciences, Beijing 100080,{3. 2. Institute of Computing technology, Chinese Academy of sciences, Beijing 100080,{3. 3. Institute of Software, Chinese Academy of sciences, Beijing 100080,{3. 4. Graduate University of Chinese Academy of sciences, Beijing 100049,{3. Academy of Mathematics and Systems science Chinese Academy of Sciences Beijing China Institute of Software Chinese Academy of Sciences Beijing China Institute of Computing technology Chinese Academy of Sciences Bejing China Graduate University of Chinese Academy of sciences Beijing China

Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.

关键词： Web service environment ontology automatic composition π calculus formal verification.

Online application of automatic surface quality inspection system to finishing line of cold rolled strips

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Journal of University of science and technology Beijing 2003年第4期10卷 38-41页

作者： Hao Sun, Ke Xu, and Jinwu XuNational Engineering Research center of advanced Rolling, University of science and {3. Beijing, Beijing 100083. china Natl. Eng. Res. Ctr. of Adv. Rolling Univ. of Sci. and Technol. Beijing Beijing 100083 China

An automatic surface quality inspection system installed on a finishing lineof cold rolled strips is introduced. The system is able to detect surface defects on cold rolledstrips, such as scratches, coil breaks, rusts, roll imprints, and so on. Multiple CCD area scancameras were equipped to capture images of strip surface simultaneously. Defects were detectedthrough 'Dark-field illumination' which is generated by LED illuminators. Parallel computationtechnique and fast processing algorithms were developed for real-time data processing. Theapplication to the production line shows that the system is able to detect defects effectively.

关键词： surface inspection cold rolled strip finishing line CCD cameras imageprocessing

SUPERCONVERGENCES OF THE ADINI'S ELEMENT FORSECOND ORDER EQUATION

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Journal of Computational Mathematics 1999年第6期17卷 569-574页

作者： Ping Luo(Department of Computer science and technology, Qinghua University, Beijing 100084,china)Qun Lin(Institute of Systems science, Academia Sinica, Beijing, 100080, china) 清华大学计算机系北京 100084 中科院系统科学所北京 100080

n this papers the asymptotic error expansions of Adini's element for the secondorder imhomogeneous Neumann problem are given and the superconvergence estimations are obtained. Moreover, a numerical example to support ... 详细信息

关键词： Adini's element Superconvergence estimation Asymptotic expansion.