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First-Principles Study of Doped Half-Metallic Spinels: Cu_(0.5)Zn0.5Cr_(2)S_(4),Cu_(0.5)Cd_(0.5)Cr_(2)S_(4), Li_(0.5)Zn_(0.5)Cr_(2)O_(4) and Li_(0.5)Zn_(0.5)Cr_(2)S_(4)

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Chinese Physics Letters 2012年第4期29卷 195-198页

作者： ZHOU Tie-Ge LIU zhi-qiang ZUO xu College of Information Technical Science Nankai UniversityTianjin 300071

Electronic structure and magnetic properties of Cu_(0.5)Zn0.5Cr_(2)S_(4),Cu_(0.5)Cd_(0.5)Cr_(2)S_(4), Li_(0.5)Zn_(0.5)Cr_(2)O_(4) and Li_(0.5)Zn_(0.5)Cr_(2)S_(4) are investigated using the first-principles calculation based on the density functional *** +U exchange correlation is used in the calculation to correct the effective Coulomb repulsion energy of Cr underestimated by LSDA or *** calculation results reveal that half-metallic Cu_(0.5)Zn_(0.5)Cr_(2)S_(4) and Cu_(0.5)Cd_(0.5)Cr_(2)S_(4) can be achieved by doping CuCr_(2)S_(4) with Zn or Cd,though CuCr_(2)S_(4) is not ***-metallic LiCr_(2)O_(4) is experimentally unstable,but half-metallic Li_(0.5)Zn_(0.5) Cr_(2)O_(4) and Li_(0.5)Zn_(0.5) Cr_(2)S_(4) can be achieved by doping Li into experimentally stable ZnCr_(2)O_(4) and ZnCr_(2)S_(4),though ZnCr_(2)O_(4) and ZnCr_(2)S_(4) are not *** influence of +U on the electronic structure and half-metallicity of the doped systems is also presented.

关键词： theory metallic

Analysis of Key Disciplinary Parameters in Floating Offshore Wind Turbines with An AI-Based SADA Method

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China Ocean Engineering 2022年第4期36卷 649-657页

作者： CHEN Peng HU zhi-qiang School of Engineering Newcastle UniversityNewcastle upon TyneNE17RUUnited Kingdom

Floating offshore wind turbines(FOWTs)are a promising offshore renewable energy harvesting facility but requesting multiple-disciplinary analysis for their dynamic performance ***,engineering-fidelity level tools and the empirical parameters pose challenges due to the strong nonlinear coupling effects of FOWTs.A novel method,named SADA,was proposed by Chen and Hu(2021)for optimizing the design and dynamic performance prediction of FOWTs in combination with AI *** the SADA method,the concept of Key Disciplinary Parameters(KDPs)is also proposed,and it is of crucial importance in the SADA *** purpose of this paper is to make an in-depth investigation of the characters of KDPs and the internal correlations between different KDPs in the dynamic performance prediction of ***,a brief description of SADA is given,and the basin experimental data are used to conduct the training process of ***,categories and boundary conditions of KDPs are *** types of KDPs are given,and different boundary conditions are used to analyze *** results show that the wind and current in Environmental KDPs are strongly correlated with the percentage difference of dynamic response rather than that by wave *** general,the optimization results of SADA consider the specific basin environment and the coupling results between different KDPs help the designers further understand the factors that have a more significant impact on the FOWTs system in a specific domain.

关键词： floating offshore wind turbine SADA KDPs machine learning basin experiment

The Compressibility of Checkerboard Surfaces of Link Diagrams

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Acta Mathematica Sinica,English Series 2007年第10期23卷 1845-1858页

作者： zhi qiang BAO LMAM School of Mathematical Sciences Peking University Beijing 100871 P. R. China

Consider the checkerboard surfaces defined by some link diagrams. When they are not orientable, one considers the boundary surfaces of small regular neighborhoods of them. This article studies the compressibility problem of these kinds of surfaces in the link complements. The problem is solved by devising a normalization theory for the compressing discs, which brings up an algorithm to read out compressibility directly from the link diagrams. As an application of the algorithm, the compressibility changes under Reidermeister moves are studied. Diagrams from the knot tables are also studied, and surprisingly, some of them are shown to define completely compressible surfaces of this kind. Infinitely many examples of non-alternating knot diagrams with incompressible surfaces of this kind are also constructed.

关键词： compressibility checkerboard surface knot diagram

The Result Integration Algorithm Based on Matching Strategy

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 113-116页

作者： xu Jia-shu YE zhi-qiang QIN Zheng Department of Computer Science and Technology Xi＇an Jiaotong University Xi＇an 710049 Shaanxi China School of Management Huazhong University of Science and Technology Wuhan 430074 Hubei China Daya Bay Nuclear Power Operations and Management Co. Ltd Shenzhen 518124 Guangdong China

The following paper provides a new algorithm： a result integration algorithm based on matching strategy. The algorithm extracts the title and the abstract of Web pages, calculates the relevance between the query string and the Web pages, decides the Web pages accepted, rejected and sorts them out in user interfaces. The experiment results in dieate obviously that the new algorithms improve the precision of meta-search engine. This technique is very useful to metasearch engine.

关键词： meta-search engine relevance Web page

Recent progress in nuclear data measurement for ADS at IMP

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Nuclear Science and Techniques 2017年第12期28卷 269-278页

作者： zhi-qiang Chen Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

Recent progress in nuclear data measurement for ADS at Institute of Modern Physics is reviewed *** on the cooler storage ring of the Heavy Ion Research Facility in Lanzhou, nuclear data terminal was *** nuclear data measurement facility for the ADS spallation target has been constructed, which provides a very important platform for the experimental measurements of spallation reactions. A number of experiments have been conducted in the nuclear data terminal. A Neutron Time-of-Flight(NTOF)spectrometer was developed for the study of neutron production from spallation reactions related to the ADS *** experiments of 400 MeV/u ^(16)O bombarded on a tungsten target were presented using a NTOF *** yields for 250 MeV protons incident on a thick grain-made tungsten target and a thick solid lead target have been measured using the water-bath neutron activation method. Spallation residual productions were studied by bombarding W and Pb targets with a 250 MeV proton beam using the neutron activation method. Benchmarking of evaluated nuclear data libraries was performed for D-T neutrons on ADS relevant materials by using the benchmark experimental facility at the China Institute of Atomic Energy.

关键词： Accelerator-driven systems Nuclear data measurement Neutron Time-of-Flight spectrometer Integral experiment Evaluated nuclear data

Numerical solution of potential flow equations with a predictor-corrector finite difference method

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第5期13卷 393-402页

作者： zhi-qiang LUO Department of System Science and Applied Mathematics School of ScienceKunming University of Science and TechnologyKunming 650083China

We develop a numerical solution algorithm of the nonlinear potential flow equations with the nonlinear free surface boundary condition.A finite difference method with a predictor-corrector method is applied to solve the nonlinear potential flow equations in a two-dimensional (2D) *** irregular tank is mapped onto a fixed square domain with rectangular cells through a proper mapping function.A staggered mesh system is adopted in a 2D tank to capture the wave elevation of the transient *** finite difference method with a predictor-corrector scheme is applied to discretize the nonlinear dynamic boundary condition and nonlinear kinematic boundary *** present the numerical results of wave elevations from small to large amplitude waves with free oscillation motion,and the numerical solutions of wave elevation with horizontal excited *** beating period and the nonlinear phenomenon are very *** numerical solutions agree well with the analytical solutions and previously published results.

关键词： Predictor-corrector method Nonlinear potential flow equations Finite difference method Staggered grid Nested iterative method

直接Z-型BAs/Ga_(2)SO范德华异质结光催化分解水研究

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原子与分子物理学报 2025年第6期42卷 10-16页

作者：许康黄欣杨志红南京邮电大学电子与光学工程学院、柔性电子(未来技术)学院南京210023 南京邮电大学理学院南京210023

基于第一性原理计算,系统研究了BAs/Ga_(2)SO异质结的光催化分解水性能.结果表明:BAs/Ga_(2)SO异质结具有良好的热力学稳定性并表现出交错的能带排列方式,带隙值为0.73 eV,界面处存在从BAs指向Ga_(2)SO的内建电场使其形成了直接Z-型异质... 详细信息

基于第一性原理计算,系统研究了BAs/Ga_(2)SO异质结的光催化分解水性能.结果表明:BAs/Ga_(2)SO异质结具有良好的热力学稳定性并表现出交错的能带排列方式,带隙值为0.73 eV,界面处存在从BAs指向Ga_(2)SO的内建电场使其形成了直接Z-型异质结,能够有效分离光生电子-空穴对.另外,异质结的带边位置可以跨越水的氧化还原电位,析氢反应发生在BAs侧而析氧反应发生在Ga_(2)SO侧.最后,基于吉布斯自由能变化计算,发现在有光照时,析氢和析氧反应在BAs/Ga_(2)SO异质结表面可自发进行.以上结果表明BAs/Ga_(2)SO异质结是有潜力的光催化分解水材料.

关键词：第一性原理计算直接Z型异质结光催化分解水吉布斯自由能

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Mathematical Basis of Idea That Harmonious Marriage Can Lengthen Life-span

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 321-326页

作者： zhi-qiang Zhang School of Mathematical Science Xiamen University Xiamen 361005 China

It is a very important issue for us to explore the effects of the marriage to life. In recent years, many scholars have proved that the marriage can lengthen life-span from different angles. With the development of theory of dependence random variables, we discuss the effects of the marriage to life and provide a mathematical basis of the idea that the harmonious marriage can lengthen life-span in this paper. Meanwhile, we analyze the impact of the marriage on life on the basis of the net single premium.

关键词： Marriage joint-life status last survivor status comonotonicity copula

Performance analysis of ARQ schemes with code combining over Nakagami-m fading channel

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 14-19页

作者： xu Wen-bo NIU Kai LIN Jia-ru HE zhi-qiang School of Information and Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article investigates the performance of hybrid automatic repeat request （HARQ） with code combining over the ideally interleaved Nakagami-m fading channel. Two retransmission protocols with coherent equal gain code combining are adopted, where the entire frame and several selected portions of the frame are repeated in protocols I and II, respectively. Protocol II could be viewed as a generalization of the recently proposed reliability-based HARQ. To facilitate performance analysis, an approximation of the product of two independent Nakagami-m distributed random variables is first developed. Then the approximate analysis is utilized to obtain exact frame error probability （FEP） for protocol I, and the upper bound of the FEP for protocol II. Furthermore, the throughput performance of both two protocols is presented. Simulation results show the reliability of the theoretical analysis, where protocol II outperforms protocol I in the throughput performance due to the reduced amount of transmitted information.

关键词： code combining HARQ Nakagami-m fading performance analysis