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Search Results: 1 - 10 of 304772 matches for " 王骋 "
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电动车辆ABS的改进线性二次型最优控制
,何仁
- , 2018, DOI: 10.11918/j.issn.0367-6234.201707171
Abstract: 为充分利用轮毂电机控制精确和响应迅速的优势,提高电动车辆制动防抱死控制的稳定性,提出一种用于轮毂电机电动车辆制动防抱死系统(ABS)协调控制的改进线性二次型最优控制方法.建立电动车辆纵向动力学模型;结合复合制动系统的协调控制策略,分析现有线性二次型最优控制算法无法用于防抱死控制器设计的原因,提出一种通过构造虚拟阻尼量以及无穷小量来建立黎卡提方程的改进型线性二次型最优控制算法,并据此设计了防抱死控制器.在高附着路面、中附着路面和低附着路面3种不同行驶工况,对分别安装有改进线性二次型最优防抱死控制器和滑模防抱死控制器的电动车辆的紧急制动性能进行了仿真分析.结果表明:在不同附着系数路面行驶工况下,改进线性二次型最优控制算法能够有效提高电动汽车防抱死控制系统的控制精度和响应速度.
To make the most of control accuracy and fast response of in-wheel motors and improve the stability of anti-lock brake system (ABS) of in-wheel motor driven electric vehicle, a design method of anti-lock controller based on the improved linear quadratic optimal control algorithm was proposed. A vehicle longitudinal dynamics model was established. The coordinated control strategy of composite braking system was applied in examining the reason for the failure of the general linear quadratic optimal control algorithm in the design of anti-lock controller. An improved linear quadratic optimal control algorithm was proposed to design the anti-lock controller through adding some virtual damping and infinitely small terms in the design process of Riccati function, based on which a anti-lock brake was subsequently designed. The control result of the proposed controller was compared with the control result of general sliding mode controller under three different road conditions with low, middle and high adhesive coefficients. Results showed that the proposed improved linear quadratic optimal control algorithm can achieve not only outstanding control accuracy but also fast response.
军民融合:21世纪反情报工作的几点探索
,刘洁,赵澄谋
图书情报工作 , 2009,
Abstract: ?从军民融合的角度,对反情报的概念、挑战、战略与趋势进行剖析。反情报是一种活动和一项产品,它面临着组织机构上的挑战、分析技能上的挑战、日常行为上的挑战与采购风险上的挑战。为了迎接这些挑战,反情报组织应制定一般战略、人力资源战略、活动战略与合作战略等反情报战略。并指出未来的反情报工作,将具有反情报研究加强、反情报责任立法与反情报全球化等发展趋势。
车辆半主动悬架全息最优滑模控制器设计方法
Design method of holographic optimal sliding mode controller for semi-active suspension of vehicle

陈士安,,姚明
- , 2016,
Abstract: 为使半主动悬架在名义工况下获得尽可能优的使用性能,保证在变参数/行驶工况下具有良好的鲁棒性,提出一种车辆半主动悬架全息最优滑模控制器设计方法。基于车辆模型分析了现有最优滑模控制器不能使半主动悬架在名义工况下获得较优性能与在变参数/行驶工况下鲁棒性较差的原因。通过对半主动悬架控制系统状态方程进行扩展,构建了不丢失任何系统结构与期望性能信息的滑模流形函数,据此设计了半主动悬架全息最优滑模控制器。通过变参数多工况数值仿真对比了采用现有最优滑模控制器的半主动悬架、采用全息滑模控制器的半主动悬架与被动悬架的性能。分析结果表明:在名义工况下,采用全息最优滑模控制器的半主动悬架的综合性能较采用现有最优滑模控制器的半主动悬架与被动悬架的综合性能分别提高了88.30%、38.33%; 在变参数工况下,采用全息最优滑模控制器的半主动悬架、采用现有最优滑模控制器的半主动悬架和被动悬架的综合性能指标的最大波动分别是26.22%、74.42%、46.39%; 在变行驶工况下,采用全息最优滑模控制器的半主动悬架、采用现有最优滑模控制器的半主动悬架和被动悬架的综合性能指标的最大波动分别是78.55%、106.22%、115.06%。可见,相比于被动悬架与采用现有最优滑模控制器的半主动悬架,采用全息最优滑模控制器的半主动悬架可获得更好的名义工况使用性能与变工况鲁棒性。
To obtain both better comprehensive performance of semi-active suspension under the nominal running condition and the enhanced robustness under the variation parameters/running condition, a design method of holographic optimal sliding mode(HOSM)controller for the semi-active suspension of vehicle was developed. First, when the current optimal sliding mode(COSM)controller was applied, the poorer reasons of the comprehensive performance of semi-active suspension under the nominal running condition and the robustness under the variation parameters/running condition were analyzed. Second, the state equations of control system for the semi-active suspension were augmented, a sliding mode manifold function considering all of structural and expected information of suspension was established, and a novel HOSM controller was designed. Finally, based on the numerical simulation, the control result of the proposed controller was compared with the control result of COSM controller and the performance of passive suspension. Analysis result shows that the comprehensive performance of semi-active suspension controlled by the HOSM controller increases by 88.30% and 38.33% compared with the values of the semi-active suspension controlled by the COSM controller and the passive suspension in the nominal running condition; under the variation parameter condition, the maximum fluctuations of comprehensive performance indexes of the suspensions controlled by the HOSM controller and the COSM controller and the passive suspension are 26.22%, 74.42%, and 46.39%, respectively; under the variation running condition, the maximum fluctuations of comprehensive performance indexes of the suspensions controlled by the HOSM controller and the COSM controller and the passive suspension are 78.55%, 106.22%, and 115.06%, respectively. Therefore, using the HOSM controller can not only achieve better comprehensive performance of semi-active suspension under the nominal running condition, but also achieve better
区域性民间金融风潮:中国式金融危机简史(1883-2015)
Regional Non-governmental Financial Agitations:A Brief History of Chinese Financial Crisis (1883-2015)


- , 2016,
Abstract: 与西方国家发生于正规金融市场、以资产价格爆跌为主要特征的金融危机不同,中国式金融危机主要表现为局部市场发生的区域性民间金融风潮,早期以钱庄等传统金融机构倒闭和挤兑狂潮为主要特征,改革开放后主要表现为非法集资信用链断裂引发的“倒会案”、机构倒闭引发的企业主跑路,以及挤兑狂潮引发的群体性事件等。根据历史资料、媒体报道及学术文献,结合田野调查,对各类民间金融风潮具体案例进行系统梳理,并通过与一般金融危机的比较分析,发现区域性民间金融风潮的演化路径也经历“疯狂——惊恐——崩溃”三个阶段,但在具体成因、影响后果上存在较大区别。民间金融风潮具体成因与市场分割、二元结构下地方金融监管体制缺陷等有关,因此,在应对措施上也应与普通金融危机不同。
Since modern finance emerged, many financial crises happened in China. Different from the financial crisis happened in regular financial market characterized with slumped asset prices in Western countries, Chinese financial crisis are regional financial agitation, which was characterized by traditional financial institutions collapses and bank run in early modern times, and by Roscas crisis, enterprise owners hiding from creditors caused by bankrupt of institutions, and mass incidents caused by credit chain rupture in informal finance. The main reason of regional financial agitations is the lack of financial regulation in market segmentation. So the solutions is different with general financial crisis. We should correct local government character and perfect local financial regulation system, on the other hand, we should strengthen the standard management of non-governmental finance.
利用检测线圈的开关磁阻电机转子位置估计方法
,邓智泉,蔡骏,胡荣光
电工技术学报 , 2015,
Abstract: 本文提出了一种新型的12/8结构开关磁阻电机的转子位置检测方法。该方法将检测线圈绕组与电机主绕组同时绕制于电机定子齿上,检测线圈的结构可有效抑制主绕组工作产生的感应电势。本文亦介绍了该结构检测线圈的参数设计原则。通过注入高频信号,电机的转子位置信号可通过处理采样电阻压降获得。由于检测线圈绕组与主绕组相互独立,因此高频信号无论转速高低均可注入,使得该方法的转速应用范围较宽。最后,本文针对一台12/8开关磁阻电机进行了仿真与实验,验证了该方法的可行性。
基于改进脉冲注入开关磁阻电机无位置传感器技术
邵杰,邓智泉,胡荣光,
电工技术学报 , 2015,
Abstract: 针对12/8极分块转子开关磁阻电机无位置传感器运行,提出一种改进的脉冲注入方法。与传统的脉冲注入方法在电机低速运行时对三相绕组的非导通区间均注入电压脉冲不同,该文提出的改进的脉冲注入方法仅对电机一相绕组的非导通区间注入电压脉冲。针对分块转子电机在非导通相注入高频脉冲信号后因响应电流较小导致采用脉冲注入方法效果变差的缺点,采取在非导通区间注入宽度逐渐增大的电压脉冲,通过响应电流峰值与阈值的比较进行转子位置估计的方法。在电机转速升高时结合电流梯度法扩大其适用范围。最后通过实验验证了所提出方法的正确性和实用性。
一种开关磁阻电机位置信号故障诊断与容错控制方法
胡荣光,邓智泉,蔡骏,
电工技术学报 , 2014,
Abstract: 开关磁阻电机正常运行需要准确可靠的位置信号。本文通过分析开关磁阻电机方波位置信号,提出一种基于边沿时刻预测的位置信号故障诊断方法。该方法利用相邻三个边沿时刻预测第四个边沿时刻,与实际边沿时刻进行对比,来判断位置信号是否故障。该算法能够准确诊断故障恢复后位置信号是否正常;该方法能独立诊断各相位置信号,且能适用于电机加减速频繁的应用场合,并可以推广应用到其他电机矩形波式位置信号的故障诊断。最后通过仿真和实验验证了该方法的正确性和可靠性。
肥胖女性膳食营养素摄入与高血压关系
,李颖,康真,孙长颢
中国公共卫生 , 2009, DOI: 10.11847/zgggws2009-25-06-57
Abstract: ?目的探讨肥胖女性膳食营养素摄入与高血压的关系。方法在黑龙江省哈尔滨市随机选择9个人口流动性小的社区,采用食物频率问卷法(FFQ)对肥胖女性进行膳食调查,计算每日膳食中营养素摄入量并测定身高、体重、血压、血糖、血脂。结果共调查肥胖女性283人,其中高血压患病率为43.62%,空腹血糖异常和2h-糖耐量异常患病率分别为12.8%和18.1%,高甘油三酯血症、高胆固醇血症、低-高密度脂蛋白胆固醇血症(HDL-C)、高-低密度脂蛋白胆固醇血症(LDL-C)的患病率分别为30.04%,13.07%,48.41%和58.30%;多因素分析结果表明,与高血压相关的膳食因素中,碳水化合物、钠是高血压的危险因素,动物性蛋白质、核黄素、尼克酸、钙、磷、锌、镁、钾、动物性铁是高血压的保护因素。结论肥胖女性应合理地调整膳食中营养素的摄入以防治高血压。
电商环境下考虑顾客偏好的寄售契约研究
宏伟,徐庆,,崔姝
复旦学报(自然科学版) , 2015,
Abstract:
刚度和阻尼系数对LQG控制主动悬架控制的影响分析
赵彩虹,陈士安,
农业机械学报 , 2015, DOI: 10.6041/j.issn.1000-1298.2015.12.041
Abstract: 分别基于半车4自由度线性与非线性车辆模型,设计了主动悬架LQG控制器,并通过理论推导和数值仿真解析了刚度和阻尼系数对悬架控制的影响。线性模型理论推导表明,LQG控制主动悬架系统的Ricatti方程的解与刚度和阻尼系数无关,进而得出了该主动悬架的时域响应与刚度和阻尼系数无关的结论。线性模型数值仿真表明,由刚度和阻尼系数产生的被动力与主动控制力组成的整体控制力相互独立且不受刚度和阻尼系数的影响;主动控制力的全局阻尼特性随着其并联阻尼的增加而明显由正特性转变为负特性。针对通用的非线性车辆模型,通过控制系统线性化、线性化后控制系统LQG控制器设计及控制反线性化这3个环节完成非线性主动悬架的LQG控制设计。设计过程表明,非线性刚度和阻尼系数的力作用在控制系统线性化和控制反线性化中被抵消,使得悬架的整体控制力不受此两系数的影响,说明以上线性主动悬架的研究结论也适用于具有非线性刚度和阻尼特性的主动悬架。
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