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建模与仿真过程中需求分析模型的校核与验证研究

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系统仿真学报 2008年第18期20卷 4806-4808页

作者：唐俊张明清叶丽君解放军信息工程大学电子技术学院郑州450004

建模与仿真(M&S)开始于对所研究问题的明确定义与清晰描述,准确完整的需求定义是确定M&S校核、验证与确认(VV&A)评估标准的依据。简要介绍了需求分析过程的阶段和需求分析模型的建立方法,分析了需求分析模型校核与验证的主要内容,并给... 详细信息

建模与仿真(M&S)开始于对所研究问题的明确定义与清晰描述,准确完整的需求定义是确定M&S校核、验证与确认(VV&A)评估标准的依据。简要介绍了需求分析过程的阶段和需求分析模型的建立方法,分析了需求分析模型校核与验证的主要内容,并给出了需求分析模型的静态校验和动态校验方法。

关键词：需求分析校核验证静态校验动态校验

Modified extremal optimization for the hard maximum satisfiability problem

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Journal of Zhejiang university-Science C(Computers and electronics) 2011年第7期12卷 589-596页

作者： Guo-qiang ZENG 1,Yong-zai LU 2,Wei-Jie MAO 2 (1 College of Physics & electronic information engineering,Wenzhou university,Wenzhou 325035,china) (2 State Key Laboratory of Industrial Control technology,institute of Cyber-Systems and Control,Zhejiang university,Hangzhou 310027,china) College of Physics & electronic information engineering Wenzhou University State Key Laboratory of Industrial Control technology Institute of Cyber-Systems and Control Zhejiang University

Based on our recent study on probability distributions for evolution in extremal optimization (EO),we propose a modified framework called EOSAT to approximate ground states of the hard maximum satisfiability (MAXSAT) problem,a generalized version of the satisfiability (SAT) *** basic idea behind EOSAT is to generalize the evolutionary probability distribution in the Bose-Einstein-EO (BE-EO) algorithm,competing with other popular algorithms such as simulated annealing and *** results on the hard MAXSAT instances from SATLIB show that the modified algorithms are superior to the original BE-EO algorithm.

关键词： Extremal optimization (EO) Evolution Probability distributions Maximum satisfiability (MAXSAT) problem

Effects of Al on Microstructure and High-Temperature Wear Properties of Austenitic Heat-Resistant Steel

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Journal of Iron and Steel Research International 2012年第3期19卷 62-66页

作者： ZHANG Yan1, SUN Yu-fu2, ZHAO Jing-yu2, GUAN Shao-kang2 (1. School of Materials engineering, Nanjing institute of technology, Nanjing 211167, Jiangsu, china 2. School of Materials Science and engineering, zhengzhou university, zhengzhou 450002, Henan, china) [a] School of Materials engineering Nanjing Institute of Technology Nanjing 211167 Jiangsu China [b] School of Materials Science and engineering Zhengzhou University Zhengzhou 450002 Henan China

Microstructure and high-temperature dry sliding wear at 600 ~C in ambient air of austenitic heat-resistant steel ZG40Cr25Ni20 with different contents （mass percent） of AI （0 to 7.10~） have been investigated. The results show that microstructures of 4.68% and 7.10% A1 addition content consist of the matrix and reinforcement of inter- metallic compound y＇ and carbide, while microstructures of ZG40Cr25Ni20 without A1 and with A1 of 1.68% are ab- sent of y＇. Higher wear resistance than the original ZG40Cr25Ni20 alloy is achieved in alloys with higher content of A1 under the same high-temperature wear test condition. The wear rates of Fe-25Cr-20Ni-7.10A1 and Fe-25Cr-20Ni- 4.68A1 are only 20.83% and 45.83% of that of Fe-25Cr-20Ni, respectively. Heat-resistant steels with higher con- tents of AI （4.72% and 7.10%） have higher hardness than those with lower contents of AI （1.68% and 0）. Wear mechanisms of ZG40Cr25Ni20 are considered as severe plough plastic deformation and slight adhesive. However, wear mechanisms of Fe-25Cr-20Ni 4.68A1 are light micro-cutting and oxidation-wear, while that of Fe-25Cr-20Ni- 7. 10A1 are severe adhesive transfer and oxidation-wear_

关键词： austenitic heat resistant steel Al microstructure high-temperature sliding wear mechanism

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遗传算法在卫星广播调度中的应用

系统工程与电子技术 2004年第2期26卷 150-152,221页

作者：李云强余昭平郑州信息工程大学电子技术学院河南郑州450004

提出了一种基于遗传算法的卫星广播调度算法。利用新的编码方法,把卫星广播调度问题和寻找满足约束条件的矩阵优化问题相对应,通过设计相应的遗传操作算子提高遗传算法的收敛性能,从而较好地实现了利用遗传算法对卫星广播的调度。在卫... 详细信息

提出了一种基于遗传算法的卫星广播调度算法。利用新的编码方法,把卫星广播调度问题和寻找满足约束条件的矩阵优化问题相对应,通过设计相应的遗传操作算子提高遗传算法的收敛性能,从而较好地实现了利用遗传算法对卫星广播的调度。在卫星个数相同条件下对三种有代表性的卫星广播调度要求进行了实验比较,说明了不同的调度要求对收敛速度的影响。遗传算法的性能决定了本文所提出的算法适用于不同规模的卫星广播调度问题,实验表明该算法是一种收敛速度快,稳定性强的高效卫星广播调度算法。

关键词：卫星广播调度遗传算法矩阵优化收敛速度卫星通信

Friction behavior of coupling motion for natural articular cartilage by reciprocating rotation

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Chinese Science Bulletin 2009年第4期54卷 576-583页

作者： QIAN ShanHua1,2,3 & GE ShiRong1,3 1 College of Mechano-electronic engineering, china university of Mining & technology, Xuzhou 221116, china 2 institute of Tribology and Reliability engineering, china university of Mining & technology, Xuzhou 221116, china 3 Biotribology Center, State Key Laboratory of Tribology, Xuzhou 221116, china College of Mechano-electronic engineering China University of Mining & Technology Xuzhou 221116 China institute of Tribology and Reliability engineering China University of Mining & Technology Xuzhou 221116 China Biotribology Center State Key Laboratory of Tribology Xuzhou 221116 China

Based on the irregular surface of natural cartilage configurations, the tribological characteristics of coupling motion between natural cartilage pairs were investigated by the variation of rotated offset and velocity. Contact displacement, contact load, friction force and coefficient of friction from natural cartilage pairs were measured by a UMT-2 testing machine. In order to obtain the steady part and wavy part, the contact load and contact displacement were decompounded by the five-point sliding average method. These results showed that the contact load was composed of steady load and wavy load. And the contact displacement was composed of cartilage deformation and surface outline. The steady load was similar to exterior load while natural cartilage deformation increased nonlinearly with the sliding time. Wavy load had the correlative coefficient 0.235 with surface outline due to the irregular surface of friction configurations. The coefficient of friction from cartilage friction configurations was less influenced by smaller magnitude in rotated parameters. A few strange summits were obtained in the area of coef-ficient of friction, and significantly related with local minimal values corresponding to the contact loads. The rotated offsets had clear impact on contact load and a slight impact on contact displacement. Larger offset produced higher wavy magnitude of the contact load. The rotated velocities played an evident role in cartilage deformation, but had a less influence on contact load. Lower velocity brought larger cartilage deformation.

关键词：软骨构造关节软骨摩擦系数软骨变形接触装

CAD/CAE OF THE WORKING CHARACTERISTICS OF A NEW TYPE OF FLUID COUPLING SHOCK ABSORBER

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Chinese Journal of Mechanical engineering 2002年第3期15卷 222-227页

作者： Yang Ping Zhong Yifang Zhou JiSchool of Mechanical Science and engineering, Huazhong university of Science and technology,Wuhan 430074, chinaLiu Yong Guilin institute of electronic technology *** School of Mechanical Science and engineering Huazhong University of Science and Technology Wuhan 430074 China

For purpose of simulation of the working characteristics of a new type offluid coupling shock absorber for vibration protection of sensitive equipment, a physical model ispresented by analyzing the internal fluid dynamic phenomenon with respect to the coupling shockabsorber and implemented in MATLAB software package. Using the model it is possible to evaluate theimportance of different factors for design of the shock absorber. In the meantime, the key-modelmachine is designed for coupling dynamic test. Comparisons with experimental results confirm thevalidity of the model. So the CAD/CAE software has been developed in MATLAB for design andexperimental test of the new coupling shock absorber.

关键词： Fluid coupling shock absorber Working characteristics Model Simulation

On the TOPS mode spaceborne SAR

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Science china(information Sciences) 2010年第2期53卷 367-378页

作者： BAI Xia 1 , SUN JinPing 2 , HONG Wen 3 & MAO ShiYi 2 1 Department of electronic engineering, Beijing institute of technology, Beijing 100081, china 2 Department of electronic engineering, Beihang university , Beijing 100191, china 3 institute of electronics,Chinese Academy of Sciences, Beijing 100190, china 1. Department of electronic engineering Beijing Institute of Technology Beijing 100081 China2. Department of Electronic Engineering Beihang University Beijing 100191 China3. Institute of Electronics Chinese Academy of Sciences Beijing 100190 China

TOPS (terrain observation by progressive scans) is a recently proposed SAR mode for wide swath acquisition, which aims at achieving the same coverage and resolution as the SCAN mode besides creating scalloping-free images. In this paper, a general SAR imaging model used in TOPS and other SAR modes is introduced, where the antenna sweep rate, Doppler centroid rate, illumination time and azimuth resolution are described by a parameter defined as the "mode factor". After analyzing the characteristics of TOPS signal, an algorithm based on chirp-z transform is proposed, in which a new de-rotation function is used. Simulation results validate the proposed algorithm.

关键词： synthetic aperture radar acquisition mode TOPS

Effect of ZnO-B_2O_3 Glass Addition on the Microwave Dielectric Properties of BaO-Nd_2O_3-TiO_2-Bi_2O_3 System

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Journal of Wuhan university of technology(Materials Science) 2010年第5期25卷 730-733页

作者：吴顺华 institute of electronic and information engineering Tianjin University

The effect of ZnO-B2O3（ZB） glass addition on the sintering behavior, microstructures and microwave dielectric properties of BaO-Nd2O3-TiO2-Bi2O3 （BNTB） system was investigated with the aid of X-ray diffraction, scanning electron microscopy and capacitance meter. It is found that the ZB glass addition, acting as a sintering aid, can effectively lower the sintering temperature of BNTB system to 850 ℃. The dielectric constant of BNTB-ZB ceramics increases with the increase of soaking time and the value of dielectric loss decreased with increasing soak time. The optical dielectric properties at 1 GHz of ε=74, tan δ=4×10^-4, and TCC=25 ppm/℃ were obtained for the BNTB system doped with 25 wt% ZB glass sintered at 850 ℃ for 2 h, representing that the BNTB-ZB ceramics could be promising for multilayer low temperature co-fired ceramics applications.

关键词： BaO-Nd2O3-TiO2-Bi2O3 ZnO-B2O3 dielectric property sintering behavior

Influence of p-layer on the performance of n-i-p μc-Si:H thin film solar cells

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Science china(Physics,Mechanics & Astronomy) 2010年第11期53卷 2042-2046页

作者： YUAN YuJie 1,2,ZHANG KaiLiang 1,2,WEI Zhen 1,2 & GENG XinHua 3 1 College of electronics information engineering,Tianjin university of technology,Tianjin 300384,china 2 Tianjin Key Laboratory of Film electronic and Communication Devices,Tianjin university of technology,Tianjin 300384,china 3 institute of Photo-electronics Thin Film Devices and Technique,Nankai university,Tianjin 300071,china 1. College of electronics information engineering Tianjin University of Technology Tianjin 300384 China2. Tianjin Key Laboratory of Film Electronic and Communication Devices Tianjin University of Technology Tianjin 300384 China3. Institute of Photo-Electronics Thin Film Devices and Technique Nankai University Tianjin 300071 China

The high pressure radio frequency plasma enhanced chemical vapor deposition (RF-PECVD) process was adopted to prepare the n-i-p microcrystalline silicon solar cells,the influence of p-type layers on the performance of the solar cells was investigated,and the optimum p layer suited to the n-i-p microcrystalline silicon solar cells was *** experimental results demonstrate that the performance of the solar cells can be highly affected by the structural and optical properties of the p-layers,and the performance of solar cells can be greatly improved by optimizing p *** have achieved an initial active-area efficiency of 8.17% (V oc =0.49 V,J sc =24.9 mA/cm 2 ,FF=67%) for the μc-Si:H single-junction n-i-p solar cells and an initial active-area efficiency of 10.93% (V oc =1.31 V,J sc =13.09 mA/cm 2 ,FF=64%) for the a-Si:H/μc-Si:H tandem n-i-p solar cells.

关键词： microcrystalline silicon solar cells quantum confinement effect p-type layers