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dependence of In—Tube Carbon Chain on the Radius and Helicity of Single—Wall Carbon Nanotubes

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Chinese Physics Letters 2002年第1期19卷 98-100页

作者：刘红董锦明等 GroupofComputationalCondensedMatterPhysics NationalLaboratoryofSolidStateMicrostructuresandDepartmentofPhysicsNanjingUniversityNanjing210093 GroupofComputationalCondensedMatterPhysics NationalLabora

Using the Lennard-Jones interaction potential, we have studied the in-tube carbon-chain structure doped into single-wall carbon nanotubes (SWCNTs). Through minimizing the potential energy of the doped system, it is found that the optimal structure of the doping carbon chain is spiral, but not a straight line, when the radius of the SWCNT is larger than about 4.30 A

关键词： linearly ordered set Multi-Walled Nanotube Radius Carbon Nanotubes Carbon Straight line Radius dependence Single-Walled Nanotube Helicity Potential energy Chains

dependence of Thermal Annealing on Transparent Conducting Properties of HoF_3-Doped ZnO Thin Films

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Chinese Physics Letters 2019年第5期36卷 75-78页

作者： Jin-Song Luo Jie Lin Li-Gong Zhang Xiao-Yang Guo Yong-Fu Zhu Key Laboratory of Automobile Materials Ministry of Educationand School of Materials Science and EngineeringJilin UniversityChangchun 130022 State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033

A kind of n-type HoF_3-doped zinc oxide-based transparent conductive film has been developed by electron beam evaporation and studied under thermal annealing in air and vacuum at temperatures 100–500℃.Effective substitutional dopings of F to O and Ho to Zn are realized for the films with smooth surface morphology and average grain size of about 50 *** hall mobility,electron concentration,resistivity and work function for the asdeposited films are 47.89 cm^2/Vs,1.39×10^(20)cm^(-3),9.37×10^(-4)Ω·cm and 5.069 eV,*** addition,the average transmittance in the visible region(400–700 nm)approximates to 87%.The HoF_3:ZnO films annealed in air and vacuum can retain good optoelectronic properties under 300℃,thereinto,more stable electrical properties can be found in the air-annealed films than in the vacuum-annealed films,which is assumed to be a result of improved nano-crystalline lattice *** optimized films for most parameters can be obtained at 200℃ for the air-annealing case and at room temperature for the vacuum annealing *** advisable optoelectronic properties imply that HoF_3:ZnO can facilitate carrier injection and has promising applications in energy and light sources as transparent electrodes.

关键词： ZnO Ho dependence of Thermal Annealing on Transparent Conducting Properties of HoF3-Doped ZnO Thin Films

dependence Analysis of the Solutions on the Parameters of Fractional Delay Differential Equations

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Advances in Applied Mathematics and Mechanics 2011年第5期3卷 586-597页

作者： Shuiping Yang Aiguo Xiao Xinyuan Pan School of Mathematics and Computational Science Hunan Key Laboratory for Computation and Simulation in Science and EngineeringXiangtan UniversityHunan 411105China Department of Mathematics Huizhou UniversityGuangdong 516007China

In this paper,we investigate the dependence of the solutions on the parameters(order,initial function,right-hand function)of fractional delay differential equations(FDDEs)with the Caputo fractional *** results includi... 详细信息

关键词： Fractional delay differential equation Caputo fractional derivative dependence

dependence Tree Structure Estimation via Copula

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International Journal of Automation and computing 2012年第2期9卷 113-121页

作者： Jian Ma Zeng-Qi Sun Sheng Chen Hong-Hai Liu Department of Computer Science Tsinghua University Beijing 100084 PRC Electronics and Computer Science Faculty of Physical and Applied Sciences University of Southampton Southampton SO17 1B J UK Faculty of Engineering King Abdulaziz University Jeddah 21589 Saudi Arabia Intelligent Systems and Robotics Research Group School of Creative Technologies University of Portsmouth Portsmouth PO1 2D J UK

We propose an approach for dependence tree structure learning via copula. A nonparametric algorithm for copula estimation is presented. Then a Chow-Liu like method based on dependence measure via copula is proposed to estimate maximum spanning bivariate copula associated with bivariate dependence relations. The main advantage of the approach is that learning with empirical copula focuses on dependence relations among random variables, without the need to know the properties of individual variables as well as without the requirement to specify parametric family of entire underlying distribution for individual variables. Experiments on two real-application data sets show the effectiveness of the proposed method.

关键词： Copula empirical copula dependence tree structure learning probability distribution.

Orientation dependence of elastic properties in orthorhombic Ca_3Mn_2O_7

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Chinese Physics B 2019年第2期28卷 369-375页

作者： Gang Jian Mei-Rui Liu Chen Zhang Jie Lu Chao Yan School of Materials Science and Engineering Jiangsu University of Science and Technology School of Materials Science and Engineering Georgia Institute of Technology Atlanta 30332

Elastic properties are important in fundamental understanding of multiferroic materials. However, up to now, there is no work about anisotropy of elastic properties in orthorhombic Ca_3Mn_2O_7. In this study, using coordinate transformation method, we investigated basic elastic parameters(elastic constants c'_(ij)) and engineering elastic parameters(Young's modulus E, Poisson's ratio v, and the rigidity modulus G') of orthorhombic Ca_3Mn_2O_7 along arbitrary orientations. The detailed anisotropic characteristics of these parameters were presented. The results reveal the orientation related elastic properties in mm2 point group orthorhombic Ca_3Mn_2O_7.

关键词： Ca3Mn2O7 elastic properties coordinate transformations orientation dependence

Inference for dependence competing risks from bivariate exponential model under generalized progressive hybrid censoring with partially observed failure causes

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Journal of Systems Engineering and Electronics 2019年第1期30卷 201-208页

作者： WANG Liang LI Huanyu MA Jin'ge School of Mathematics and Statistics Xidian University

Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes, the maximum likelihood estimators are established, and the approximate confidence intervals are also constructed via the observed Fisher information ***, Bayes estimates and highest probability density credible intervals are presented and the importance sampling technique is used to compute corresponding results. Finally, the numerical analysis is proposed for illustration.

关键词： dependence competing risk generalized progressive hybrid censoring bivariate exponential distribution Bayesian inference.

Reliability and Availability Models of Belt Drive Systems Considering Failure dependence

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 133-144页

作者： Peng Gao Liyang Xie Jun Pan School of Mechanical Engineering Liaoning Shihua University School of Mechanical Engineering and Automation Zhejiang Sci-Tech University School of Mechanical Engineering and Automation Northeastern University

Conventional reliability models of belt drive systems in the failure mode of fatigue are mainly based on the static stress strength interference model and its extended models, which cannot consider dynamic factors in the operational duration and be used for further availability analysis. In this paper, time-dependent reliability models, failure rate models and availability models of belt drive systems are developed based on the system dynamic equations with the dynamic stress and the material property degradation taken into account. In the proposed models, dynamic failure dependence and imperfect maintenance are taken into consideration. Furthermore, the issue of time scale inconsistency between system failure rate and system availability is proposed and addressed in the proposed system availability models. Besides, Monte Carlo simulations are carried out to validate the established models. The results from the proposed models and those from the Monte Carlo simulations show a consistency. Furthermore, the case studies show that the failure dependence, imperfect maintenance and the time scale inconsistency have significant influences on system availability. The independence assumption about the belt drive systems results in underestimations of both reliability and availability. Moreover, the neglect of the time scale inconsistency causes the underestimate of the system availability. Meanwhile, these influences show obvious time-dependent characteristics.

关键词： Availability Reliability Belt drive Failure dependence Time scale inconsistency

Time-variant fragility analysis of the bridge system considering time-varying dependence among typical component seismic demands

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 363-377页

作者： Song Shuai Qian Yongjiu Liu Jing Xie Xiaorui Wu Gang Department of Civil Engineering Taiyuan University of Technology Department of Bridge Engineering Southwest Jiaotong University Department of Environmental Science Baylor University Southwest Municipal Engineering Design and Research Institute of China School of Civil Engineering and Architecture East China Jiaotong University

This paper presents a copula technique to develop time-variant seismic fragility curves for corroded bridges at the system level and considers the realistic time-varying dependence among component seismic demands. Based on material deterioration mechanisms and incremental dynamic analysis, the time-evolving seismic demands of components were obtained in the form of marginal probability distributions. The time-varying dependences among bridge components were then captured with the best fitting copula function, which was selected from the commonly used copula classes by the empirical distribution based analysis method. The system time-variant fragility curves at different damage states were developed and the effects of time-varying dependences among components on the bridge system fragility were investigated. The results indicate the time-varying dependence among components significantly affects the time-variant fragility of the bridge system. The copula technique captures the nonlinear dependence among component seismic demands accurately and easily by separating the marginal distributions and the dependence among them.

关键词： system fragility chloride corrosion time-varying dependence copula function probabilistic seismic demand

Phonon Limited Electron Mobility in Germanium FinFETs:Fin Direction dependence

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Chinese Physics Letters 2019年第2期36卷 54-58页

作者： Ying Jing Gen-Quan Han Yan Liu Jin-Cheng Zhang Yue Hao Key Laboratory of Wide Band-Gap Semiconductor Technology School of MicroelectronicsXidian University

We investigate the phonon limited electron mobility in germanium(Ge) fin field-effect transistors(FinFETs)with fin rotating within(001),(110),and(111)-oriented wafers. The coupled Schrodinger-Poisson equations are solved self-consistently to calculate the electronic structures for the two-dimensional electron gas, and Fermi's golden rule is used to calculate the phonon scattering rate. It is concluded that the intra-valley acoustic phonon scattering is the dominant mechanism limiting the electron mobility in Ge FinFETs. The phonon limited electron motilities are influenced by wafer orientation, channel direction, in thickness Wfin, and inversion charge density Ninv. With the fixed Wfin, fin directions of(110),(112) and(110) within(001),(110), and(111)-oriented wafers provide the maximum values of electron mobility. The optimized for mobility is also dependent on wafer orientation and channel direction. As Ninv, increases, phonon limited mobility degrades, which is attributed to electron repopulation from a higher mobility valley to a lower mobility valley as Ninv increases.

关键词： Phonon Limited Electron Mobility Fin Direction dependence