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风险概念分析

系统工程学报 2001年第5期16卷 402-406页

作者：丁义明方福康北京师范大学系统科学系北京师范大学非平衡系统研究所北京100875

分析了风险的概念 ,介绍了不确定性经济学、保险和金融三个领域中与风险有关的概念 (效用函数 ,风险厌恶 ,保险 ,金融风险 )和各自关心的主要问题 (如风险的衡量 ,保费的确定 ,资产价格波动 ) ,以及一些重要结论 (Pratt定理等 ) .

关键词：风险概念分析复杂系统金融

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遗传算法在控制工程中的自调整技术研究

计算机工程与应用 2003年第20期39卷 210-212页

作者：贺素良喻寿益中南大学信息科学与工程学院株洲工学院电气工程系株洲412008

文章总结了遗传算法在控制工程中自调整技术的最新进展,并用测试实例说明了具有良好自调整技术遗传算法的优越性,希望能为从事遗传算法应用研究的自动控制或电力工作者开拓一些新思路,为设计和开发遗传算法在控制领域的应用提供指导性... 详细信息

文章总结了遗传算法在控制工程中自调整技术的最新进展,并用测试实例说明了具有良好自调整技术遗传算法的优越性,希望能为从事遗传算法应用研究的自动控制或电力工作者开拓一些新思路,为设计和开发遗传算法在控制领域的应用提供指导性的参考。

关键词：遗传算法自调整技术控制工程

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大蒜播种机蒜瓣自动定向控制装置的试验研究

农业装备与车辆工程 2009年第10期47卷 28-29,37页

作者：荐世春刘云东山东省农业机械科学研究所山东济南250100 中国农业机械化科学研究院北京100083

在对蒜瓣外形特征参数进行测量并统计研究等基础上,设计了一种基于大蒜蒜瓣自身摩擦特性、且适应各类蒜瓣不同物理特性的锥形螺旋导种管式自动定向控制装置,并确定了它的参数和结构型式。

关键词：蒜瓣锥形螺旋导种管自动定向控制装置

轴径向反应器的模拟及其在乙苯脱氢装置的应用

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石油化工 2003年第3期32卷 237-241页

作者：徐志刚俞丰朱子彬朱中南王录杰刘宝龙华东理工大学化工学院上海200237 抚顺石化分公司化工塑料厂辽宁抚顺113015

建立了轴径向床的二维流动模型和二维流动拟均相反应器模型,模拟和分析了30kt/a乙苯脱氢轴径向反应器的流场、温度场和浓度场,总结了抚顺石化公司30kt/a苯乙烯装置,应用多批不同型号的催化剂的使用效果。工业实践表明乙苯脱氢轴径向反... 详细信息

建立了轴径向床的二维流动模型和二维流动拟均相反应器模型,模拟和分析了30kt/a乙苯脱氢轴径向反应器的流场、温度场和浓度场,总结了抚顺石化公司30kt/a苯乙烯装置,应用多批不同型号的催化剂的使用效果。工业实践表明乙苯脱氢轴径向反应器的开发是成功的。

关键词：轴径向反应器模拟乙苯脱氢装置应用

Simulation on Vertical Via Interconnection Using Matrix-penciled Moment Method in Microwave Multi-Chip Module

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Simulation on Vertical Via Interconnection Using Matrix-penc...

A COUPLED MODEL OF HYDRODYNAMICS AND WATER QUALITY FOR YUQIAO RESERVOIR IN HAIHE RIVER BASIN

2.07 5th International Conference on Microwave and Millimeter Wave Technology(ICMMT’2.07)

作者： Ji Wu-sheng 1,2.Xiao Jian-kang 3,Xie Yong-jun 1 1.School of Electronic engineering,Xidian University,Xi’an,710071,china 2.Lanzhou City University,Lanzhou,730070,china 3.School of Communication and Information engineering,Shanghai University,Shanghai,2.0072.china

In the multi-chip module,signal transmission lines such as striplines or microstrip lines at different layers are connected through *** is very important to research the characteristics of via because of the signal transmission discontinuity it *** this paper,the matrix-penciled moment method is applied to analyze and compute the scattering parameters of via in a multi-layered module,and some important laws of scattering characteristics of the via are obtained,and the correctness of the calculated results are demonstrated as well.

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Journal of Hydrodynamics 2008年第5期20卷 574-582页

作者： LIU Xiao-bo PENG Wen-qi HE Guo-jian LIU Jing-ling WANG Yu-chun School of Environment Beijing Normal University Beijing 100875 China Department of Water Environment China Institute of Water Resources and Hydropower Research Beijing100038 China Department of Hydraulic engineering State Key Laboratory of Hydroscience and Engineering TsinghuaUniversity Beijing 100084 China

In order to simulate the characteristics of hydrodynamic field and mass transport processes in the Yuqiao Reservoir （YQR）, a 2.D coupled model of hydrodynamics and water quality was developed, and the water-quality related state variables in this model included CODMn, TN and TP. The hydrodynamic model was driven by employing observed winds and daily measured flow data to simulate the seasonal water cycle of the reservoir. The simulation of the mass transport and transformation processes of CODMn, TN and TP was based on the unsteady diffusion equations, driven by observed meteorological forcing and external loadings, with the fluxes form the bottom of reservoir and the plant photosynthesis and respiration as internal sources and sinks. A finite volume method and Alternating Direction Implicit （ADI） scheme were used to solve these equations. The model was calibrated and verified by using the data observed from YQR in two different years. The results showed that in YQR, the wind-driven current was an important style of lake current, while the concentration of water quality item was decreasing from east to west because of the external pollutant loadings. There was a good agreement between the simulated and measured values, with the minimal calculation error percent of 0.1% and 2.6% and the mean error percent of 44.0% and 51.2. for TN and TP separately. The simulation also showed that, in YQR, the convection was the main process in estuaries of inflow river, and diffusion and biochemical processes dominate in center of reservoir. So it was necessary to build a pre-pond to reduce the external loadings into the reservoir.

关键词： model simulation Yuqiao Reservoir (YQR) wind driven current water quality

Multi-Step Amplitude Quantization for Ultralow Sidelobe Phased Arrays by Direct Optimization Synthesis

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Journal of Systems engineering and Electronics 2001年第1期12卷 65-69页

作者： Zhu Huan Wang Yixin Xu Xiaowen & Li Shizhi Dept. of Electronic engineering, Beijing institute of Technology, 100081, P. R.{2. Dept. of Electronic engineering Beijing Institute of Technology 100081 P. R. China

In this paper, a new amplitude quantization synthesis method for ultralow sidelobe phased arrays is proposed, which is based on the constrained nonlinear optimization algorithm. By introducing a set of critical constraint conditions into the optimization model, we can directly quantize the amplitude distribution instead of replacing it with a continuous equivalent aperture antenna. The mutual coupling and the element patterns are also considered in the quantization synthesis. Finally, some array simulation results are given to show the effectiveness of the method.

关键词： Algorithms Computer simulation Directional patterns (antenna) Directive antennas Mathematical models Optimization Vector quantization

AERODYNAMIC CHARACTERISTICS ABOUT MINING DUMP TRUCK AND THE IMPROVEMENT OF HEAD SHAPE

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Journal of Hydrodynamics 2008年第6期20卷 713-718页

作者： WEI Xiu-ling WANG Guo-qiang FENG Su-li College of Mechanical Science and engineering Jilin University Changchun 130022 China Department of Aeronautic Mechanical engineering Aviation University of Air force Changchun 130022 China Fundamental Science Department Armor Technique Institute Changchun 130117 China

The external flow field around a certain mining dump truck was simulated. The airflow structure and the aerodynamic drag were discussed, and the relationship between airflow characteristics and aerodynamic drag were obtained. In order to solve the problem of head shape of the truck, three scenarios including edge rounding, installing splitter planes and their combination were put forward to improve the head shape through numerical simulation and analysis. The model and method were selected to be three dimensional and time-independent. The Reynolds-averaged Navier-Stokes equations were solved using the finite volume method. The RNG k-ε model was chosen for the closure of the turbulent quantities. The results show that the third scenario is the best one, because of its aerodynamic characteristics being better than those of unimproved model.

关键词： dump truck external flow field numerical simulation

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邦朗电站进水口拦污栅振动试验研究

水力发电学报 2003年第1期22卷 76-82页

作者：张绍春赵钟民陈兆新国家电力公司昆明勘测设计研究院昆明650033 云南澜沧江水电开发有限责任公司昆明650011

本文介绍了邦朗电站进水口拦污栅振动的研究方法和成果 ,通过测量栅条的激振力频率和结构自振频率 ,判断栅条发生共振的可能性 ,经过修改后的拦污栅结构可避免共振发生。

关键词：邦朗电站进水口拦污栅振动试验水工结构