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Electronic Structures and Properties of V, Nb and Ta Metals

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Journal of Central South university 2000年第1期12卷 7-11页

作者： HE Yu,XIE You qing (department of Materials Science and Engineering, Central South university of Technology, Changsha 410083. china) department of Materials Science and Engineering Central South University of Technology Changsha China

The electronic structures of pure V, Nb and Ta metals with bcc structure were determined by one atom (OA) theory. According to the electronic structures of these metals, their potential curves, cohesive energies, lattice parameters, elasticity and the dependence of linear thermal expansion coefficients on temperature were calculated. The electronic structures and characteristic properties of these metals with fcc and hcp structures and liquid states were studied.

关键词： electronic structure potential curve cohesive energy lattice parameter elasticity linear thermal expansion efficient V Nb Ta

A GENERALIZATION OF ROUTH-HURWITZCRITERION

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Systems Science and Mathematical Sciences 1999年第1期12卷 45-48页

作者： YANG Xiaojing (department of Mathematics, Tsinghua university, Beijing 100084, china) 清华大学数学系北京

This paper presents a criterion for a polynomial to be non-unstable and for the calculation of the number of eigenvalues which have zero real parts and negative real *** generalizes the Routh-Hurwitz criterion and is ... 详细信息

关键词： Routh-Hurwitz criterion stable polynomial.

Adsorption Efficiency of Cesium during the Activation Process for NEA GaAs Photocathode

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Adsorption Efficiency of Cesium during the Activation Proces...

THE RELATIONSHIPS OF THREE ELEMENTARY CELLULAR AUTOMATA

2010 International Conference on Semiconductor Laser and Photonics (ICSLP 2010)

作者： Jun Niu and Ge Zhang department of Electron and Electric Nanyang Institute of Technology Nanyang Henan Province 473.04 china Yijun Zhang Benkang Chang School of Electronic Engineering and Optoelectronic Technology nanjing university of Science and Technology {3. Jiangsu Province china

Photocathode materials with the lower surface doping density need the longer time to arise photocurrent during the first cesium activation process when the system’s vacuum level is not high enough, and which can be found from the photocurrent curves arising during the activation process for Negative-electron-affinity （NEA） GaAs photocathodes. At the same time, with the enhancement of system’s vacuum level, these differences in time will become not obvious. It is indicated that the adsorption efficiency of cesium on the cathode surface has the direct relationships with the surface doping density and the system’s vacuum level. In order to analyze these relationships quantitively, in this paper, a mathematical model of the adsorption efficiency of cesium on the cathode surface was established according to the experimental data. The simulation results by the model are in good agreement with the experimental phenomenon. This study has very important value and significance for the farther investigations on the structure design and preparation techniques for varied doping GaAs photocathode materials.

关键词： Photocathode Adsorption efficiency Vacuum level Doping density

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Journal of Systems Science & Complexity 2006年第1期19卷 128-136页

作者： Zhisong JIANG department of Mathematics East China University of Science and Technology Shanghai 200237 China

Limit language complexity of cellular automata which is first posed by S. Wolfram has become a new branch of cellular automata. In this paper, we obtain two interesting relationships between elementary cellular automata of rules 126, 146（182） and 18, and prove that if the limit language of rule. 18 is not regular, nor are the limit languages of rules 126 and 146（182）.

关键词： Cellular automata grammatical complexity limit language.

From Micro to Macro:A Study on the Adaptability Model of Learning Organizational Change

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From Micro to Macro:A Study on the Adaptability Model of Lea...

A Regression Analysis Model Based on Wavelet Networks

2010 2nd International Conference on Modeling, Simulation,and Visualization Methods(WMSVM 2010)

作者： Ying Peng1,2,Jinling Hou1,Jing Wang1 School of Economics and Management,nanjing university of Posts and Telecommunications1 School of Business,nanjing university 2 nanjing,china

Since 1990s,learning organization is considered as a new trend and an ideal mode of the global organizational management in the knowledge economy *** to the research of learning organization change with attributes of complex system,the theory of complex adaptive system provides a possible way on *** paper reviews theory of complex adaptive system and learning organization,analyzes the adaptability of learning organizational change,and gives the conceptual *** this paper elaborates evolution mechanism of learning organizational change,and extracts the impact *** order to obtain information accurately and timely,the overall and comprehensive effects can only play depending on the collaboration among the adaptive *** enterprises in reality should reduce the risks of adjusting organizational elements to adapt to the environment changing bigger and faster than their *** conclusion of this study is some referentially significant for those who try to promote the level of the organization's adaptability.

关键词： CAS learning organization organization change adaptability model

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Systems Science and Systems Engineering 2002年第1期11卷 123-128页

作者： XIONG Zheng-feng department of Mathematics, Zhejiang university, Hangzhou 3.0027, china department of Mathematics Zhejiang University Hangzhou 310027 China

In this paper, an approach is proposed to combine wavelet networks and techniques of regression analysis. The resulting wavelet regression estimator is well suited for regression estimation of moderately large dimensi... 详细信息

关键词： frame wavelet networks regression estimator

High frequency of p53.intronic point mutations in laryngeal squamous cell carcinoma

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Progress in Natural Science:Materials International 2004年第7期 36-40页

作者： ZHAO Xu 1*, LI Fucai 1*, SONG Yutong 2, LI Yinghui 1, FU Weineng 1, XU Zhenming 3.and SUN Kailai 1(1. department of Medical Genetics, china Medical university, Shenyang 110001, china 2. department of Biochemistry and Molecular Biology, china Medical university, Shenyang 110001, china 3. department of Otolaryngology, No.463.Hospital of Air-Force, Shenyang 110001, china) department of Medical Genetics China Medical University Shenyang 110001 China department of Biochemistry and Molecular Biology China Medical University Shenyang 110001 China department of Otolaryngology No.463 Hospital of Air-Force Shenyang 110001 China

Intronic point mutations are rare and totally unknown for human laryngeal squamous cell carcinoma (LSCC). To explore the relationship of p53.gene intronic mutation to the development of human LSCC, DNA was extracted from both tumor tissues and matched normal tissues of 55 patients with LSCC in northeast of china. Polymerase chain reaction amplification-single strand conformational polymorphism (PCR-SSCP) combined with silver staining and DNA direct sequencing were used to detect mutations in exons 7～8 (p53.7 and p53.8) and introns 7～8 (p53.7 and p53.8) of p53.gene. The p53.7 mutation was detected in 17 out of 55 patients, and the p53.7 mutation in 21 patients. No mutation was found at p53.8 or p53.8 site. The difference between tumor group and paired normal group on the rates of both p53.7 and p53.7 mutations was statistically significant. The rate of p53.7 mutations in tumor tissue was higher than that of normal tissue, and so was that of p53.7. Sequence analysis revealed that most p53.7 mutations were at the nucleotides in the branch point sequence or the polypyrimidine tract in the 3.-splice acceptor site of the intron 7. The high incidence of p53.gene intronic mutation in LSCC indicates that genetic changes within the noncoding region of the p53.gene may serve as an alternative mechanism of activating the pathogenesis of human laryngeal squamous cell carcinoma. Mutations in the noncoding region of this gene should be further studied.

关键词： laryngeal squamous cell carcinoma p53.gene intronic mutation PCR-SSCP.

Two-dimensional simulation of Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect

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Progress in Natural Science:Materials International 2007年第12期17卷 1389-1396页

作者： Hu Jun1 and Yin Xieyuan2(1. Institute of Applied Physics and Computational Mathematics, Beijing 100088, china 2. department of Modern Mechanics, university of Science and Technology of china, Hefei 23.027, china) Institute of Applied Physics and Computational Mathematics Beijing 100088 China department of Modern Mechanics University of Science and Technology of China Hefei 230027 China

Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect are directly simulated by a mixed finite element method. A temperature perturbation is used as an initial disturbed source for the basic parallel flows. The whole spatio-temporal evolution of the binary fluid flows is exhibited: initially only the disturbed mode with the wavenumber k=π is amplified while others are damped, and continuously the amplified mode grows further and the nonlinear effect becomes important; after a nonlinear evolution transition the flow system evolves finally into a periodic right traveling wave.

关键词： Poiseuille-Rayleigh-Bénard flow Soret effect through-flow.

AN INVESTIGATION OF HOT FILM SIGNALS ON LOCATING BOUNDARY LAYER TRANSITION

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Transactions of nanjing university of Aeronautics and Astronautics 1994年第1期11卷 107-109页

作者： Wang Tiecheng(department of Aerodynamics,NUAA29 Yudao Street,nanjing 210016,P.R.china)

The abilities of several hot film signals, such as mean voltage, fluctuating voltage and oscillogram of voltage are comparatively studied to locate boundary layer transition. The features of these hot film signals are... 详细信息

关键词： wind tunnel test boundary layer transition measurement surface hot film gage