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The Study of Pre-sight for the Air Transportation Systems

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The Study of Pre-sight for the Air Transportation Systems

2010 International Conference on Services Science, Management and Engineering (SSME 2010)

作者： Wenzhi Zhao Economic and Management school Civil Aviation university of china Tianjin china 300300 Zhi Guo Social and Art school Civil Aviation university of china Tianjin china 300300

The internal reasons of the deceptive air crashes were studied for the purpose of explanation its nature to reduce the accidents and the *** approach of synthetic comparison is *** Concorde aircraft accident was analyzed detailed to recognize what the real human error is. All the passengers were killed in the *** similar accidents relating aircraft DC-10,Tu-154 and Tu-144 were discussed about the risk perception of the pilots and system. Certain higher survival rate was reached in these *** the conclusion is obtained that the real problem is the lack of pre-sight for the risk in operation and system management relating to the pilots and the *** conclusion suggests some changes be made in complex system management regulations and in thinking mode for the general applications to safety.

关键词： pre-sight system control and management complex system air transport safety risk perception

An Integrative Modeling Method and Stability Analysis of Higher Order DC-DC Converters

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An Integrative Modeling Method and Stability Analysis of Hig...

11th International Conference on Electrical Machines and Systems

作者： Wang Shi-Bing~(1 2) Zhou yufei~(1*) Chen Jun-Ning~1 Jiang Xue-Dong~1 1 school of Electronic Science and Technology Anhui university china 2 school of Computer and Information Fuyang Teachers College china school of Computer and Information Fuyang Teachers College Fuyang China school of Electronic Science and Technology Anhui University Hefei China

ISBN: (纸本)9787506292214

＜正＞Aiming at strong nonlinearity and complexity of higher order switching converters,an integrative modeling method was proposed by integrating the state-space average modeling approach with the discrete-time modeling approach, based on which,stability analysis of current-mode controlled higher order switching converters was carried out,and the relation between the stability and the circuit parameters was *** results of simulation verify the validity of the modeling method and stability analysis,and show the dynamical behaviors by means of bifurcation diagram,Lyapunov exponent, phase portrait,FFT spectrum.

关键词： Stability analysis Switching converters Switches Bifurcation Pulse width modulation converters Chaos Circuits Pulse width modulation Diodes Inductors

Electronic structure and magnetic properties of metastable SmCo_(7) compound

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Science china(Physics,Mechanics & Astronomy) 2005年第3期48卷 325-335页

作者： ZHANG Changwen 1 , LI Hua 1 , DONG Jianmin 1 , WANG Yongjuan 1 , PAN Fengchun 1 , ZHANG Jian 1 , GUO Yongquan 2 & LI Wei 2 1. school of Physics and Microelectronics, Shandong university, Jinan 250100, china 2. Institute of Functional Materials, Central Iron and Steel Research Institute, Beijing 100081, china school of Physics and Microelectronics Shandong University Jinan China Institute of Functional Materials Central Iron and Steel Research Institutes Beijing China

The electronic density of states, spin-splittings and atomic magnetic moments of SmCo 7 compound have been studied using spin-polarized MS-Xα method. The results show that a few of electrons are transferred to Sm(5d 0 ) orbital because of orbital hybridization between Sm and Co atoms in the compound. The exchange interactions between 3d and 5d electrons lead to the magnetic coupling between Sm and Co, and therefore, result in the long-range ferromagnetic order inside the SmCo 7 compound. There are negative exchange couplings occurring at some levels, which weakens the strength of average coupling around Co lattice. So, the Curie temperature and Co-moment of SmCo 7 decrease distinctly compared with pure Co. Compared with SmCo 5 compound, the disordered substitution of Co-Co “dumbbell-atom” pairs for Sm changes the local environment of Co lattice, which makes the 2e site bear negative magnetic moment. The strength of hybridization near Fermi level weakens and the free energy of the compound increases obviously. Thus, SmCo 7 is a metastable compound at room temperature. Considering the localization of 4f electrons and a few of 5d electrons arising from the orbital hybridization, the magnetic moment of Sm atom will be 1.61μ B in SmCo 7 compound, which is in agreement with the experimental values of Sm 3+ ion- moment and Sm atom-moment in metals.

关键词： electronic structure, spin polarization, atomic magnetic moment, exchange coupling, Curie temperature.

An Exploratory Study of E-Business Success Factors

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Journal of Electronic Science and Technology of china 2004年第3期2卷 167-172页

作者： LI Jingting, HUANG Jinghua (school of Economic Management, Tsinghua university Beijing 100084 china) school of Economic Management Tsinghua University Beijing 100084 China

E-business success factors are Important for traditional enterprises to implement e-business. This topic is attracting more and more researchers to study. This paper makes an exploratory study on the factors influencing e-business success. Firstly, based on the literature review, 52 factors are suggested. Secondly, two rounds of survey with Delphi method are conducted. Qualitative and quantitative analysis are used to identify 57 factors. This is the foundation of empirical study.

关键词： e-business success factors comprehensive factors web features and functions

Experimental study on high viscosity fluid micro-droplet jetting system

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Science china(Technological Sciences) 2010年第1期53卷 182-187页

作者： SHU XiaYun1,2,ZHANG HongHai1,2,LIU HuaYong1,2,XIE Dan1,2 & XIAO JunFeng1,2 1 school of Mechanical Science and Engineering,Huazhong university of Science and Technology,Wuhan 430074,china 2 Division of MOEMS,Wuhan National Laboratory of Optoelectronics,Wuhan 430074,china school of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan China Division of MOEMS Wuhan National Laboratory of Optoelectronics Wuhan China

Fluid dispensing is a method by which fluid materials(such as epoxy,adhesive,and encapsulant) are delivered in a controlled manner in electronics *** jetting,derived from inkjet technology,is a noncontact,data-driven fluid dispensing *** ideal fluid materials for packaging are usually high viscous,which is difficult to realize by traditional inkjet *** this paper,a mechanical micro-droplet jetting system for high viscosity fluid was *** consists of dispensing valve,motion stage,temperature control subsystem,pneumatic subsystem,driving circuit for solenoid valve,and system control *** of this system under various circumstances was studied by changing several parameters,including working temperature,stroke length,back pressure and drive pulse *** droplets of 0.35 mm in diameter were produced by stainless steel nozzle of 0.2 mm in diameter in the experimental study.

关键词： high viscosity fluid micro-jetting microelectronics packaging

Molten Salts/Ceramic-Foam Matrix Composites by Melt Infiltration Method as Energy Storage Material

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Journal of Wuhan university of Technology(Materials Science) 2009年第4期24卷 651-653页

作者：吴建锋 school of Materials Science and Engineering Wuhan University of Technology

A new type of high temperature energy storage material was obtained through the melt infiltration method, using compounding SiC ceramic foam as matrix and Na2SO4 as phase change material. The resulting composite material was measured by XRD, SEM, TG-DSC methods. The experimental results indicate that the composite is composed of silicon carbide, sodium sulfate and square quartz, and no chemical reactions occurs between Na2SO4 and SiC matrix. Na2SO4 has a good bonding with the SiC ceramic foam matrix. As the composite material is characterized by high thermal energy storage density and high thermal conductivity, it is suit for energy storage under high temperature.

关键词： infiltration salt/ceramics SiC energy storage phase change materials ceramic foam

Effect of cold-rolling on tensile strength of SiCw/Al composite

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Rare Metals 2003年第4期22卷 285-288页

作者： ZHANGWenlong ZHANGMu GUMingyuan WANGDezun YAOZhongkai StateKeyLabofMMCs ShanghaiJiaotongUniversityShanghai200030China schoolofMaterialsScienceandEngineering HarbinInstituteofTechnologyHarbin150001China

SiC_w/Al composite was fabricated through a squeeze cast route and coldrolled to about 30 percent, 50 percent and 70 percent reduction In thickness, respectively. Thelength of whiskers in the composite before and after rolling was examined using SEM. Some of therolled composites were recrystallization annealed to remove the work hardening of matrix alloy. Thetensile strength of the rolled and annealed SiC_w/Al composites was examined and then associatedwith the change of the whisker length and the work hardening of matrix alloy. It was found that thetensile strength is a function of the degree of cold rolling. For the cold rolled composites, withthe increase in the degree of cold rolling, the tensile strength increases at first, and decreaseswhen the degree of cold rolling exceeds 50 percent. For the annealed ones, however; the tensilestrength decreases monotonously with the increase in rolling degree. The different changes intensile strength between the rolled and annealed composites could be attributed to the result of thecompetition between the work hardening of matrix resulting from the cold rolling and the worksoftening arising from the change of whisker length.

关键词： metal matrix composites tensile strength cold rolling microstructure

DNA sequencing analysis the nuclear localization signal and nuclear export signal of TRF1 in Non-Small Cell Lung Cancer

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DNA sequencing analysis the nuclear localization signal and ...

2008年浙江省胸心外科学学术年会暨浙江省医学会胸心外科学分会体外循环学组、胸腔镜学组成立大会

作者： Hu Jian~1,Sun Li~2,Wang Lu-ming~1,Jiang Su-jun~2 1 Department of Thoracic and Cardiovascular Surgery,The First affiliated hospital,College of Medicine, Zhejiang university,Hangzhou 310003,china 2 school of Medical,Hangzhou Normal university,Hangzhou,310036,china Correspondence to:Hu Jian,Department of Thoracic and Cardiovascular Surgery,The First affiliated hospital,College of Medicine,Zhejiang university,No79,Qingchun Road,Hangzhou,310003,Zhejiang,china

Background Lung cancer is the most common human malignant ***-small cell lung carcinoma(NSCLC) accounts for about 80%of all lung *** are composed of tandem arrays of a short DNA sequence,5’(GTTAGGG)n3’ in vertebrate...

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Adsorptive desulfurization on a heteroatoms Y zeolite prepared by secondary synthesis

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Science china Chemistry 2010年第1期53卷 281-286页

作者： TANG Ke1,HONG Xin1,ZHAO YongHua1,SONG LiJuan2 & SUN ZhaoLin2 1school of Material and Chemical Engineering,Liaoning Institute of Technology,Jinzhou 121001,china 2College of Petrochemical Engineering,Liaoning university of Petroleum & Chemical Technology,Fushun 113001,china school of Material and Chemical Engineering Liaoning Institute of Technology Jinzhou China College of Petrochemical Engineering Liaoning University of Petroleum & Chemical Technology Fushun China

Gallium atoms have been introduced into the framework of Y zeolite by treating the zeolite with an aqueous solution of ammonium hexafluoro *** of various model fuels containing about 500 μg/g sulfur has been studied over the synthesized Y zeolite(GaAlY).The sulfur adsorption capacity is 7.0,17.4,14.5,16.9,6.9 and 5.8 mg(S)/g adsorbent for thiophene,tetrahydrothiophene(THT),4,6-dimethyldibenzothiophene(4,6-DMDBT),dibenzophiophene(DBT),benzothiophene(BT) and 4-methyldibenzothiophene(4-MDBT),*** charges on the S atom in thiophene,THT,4,6DMDBT,DBT,BT and 4-MDBT,calculated using the density functional theory(DFT),are-0.159,-0.298,-0.214,-0.211,-0.193 and-0.188,respectively,implying that the S-M bond between the adsorption sites and thiophene is much weaker than that between the adsorption sites and THT,4,6-DMDBT or *** sulfur removal of FCC gasoline on GaAlY is 68%.

关键词： isomorphous substitution DFT model fuels adsorptive desulfurization