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Sensor Configuration and Test for Fault Diagnoses of Subway Braking System Based on Signed Digraph Method

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 475-482页

作者： ZUO Jianyong chen zhongkai Institute of Railway and Urban Mass Transit Tongji University

Fault diagnosis of various systems on rolling stock has drawn the attention of many researchers. However, obtaining an optimized sensor set of these systems, which is a prerequisite for fault diagnosis, remains a major challenge. Available literature suggests that the configuration of sensors in these systems is presently dependent on the knowledge and engineering experiences of designers, which may lead to insufficient or redundant development of various sensors. In this paper, the optimization of sensor sets is addressed by using the signed digraph （SDG） method. The method is modified for use in braking systems by the introduction of an effect-function method to replace the traditional quantitative methods. Two criteria are adopted to evaluate the capability of the sensor sets, namely, observability and resolution. The sensors configuration method of braking system is proposed. It consists of generating bipartite graphs from SDG models and then solving the set cover problem using a greedy algorithm. To demonstrate the improvement, the sensor configuration of the HP2008 braking system is investigated and fault diagnosis on a test bench is performed. The test results show that SDG algorithm can improve single-fault resolution from 6 faults to 10 faults, and with additional four brake cylinder pressure （BCP） sensors it can cover up to 67 double faults which were not considered by traditional fault diagnosis system. SDG methods are suitable for reducing redundant sensors and that the sensor sets thereby obtained are capable of detecting typical faults, such as the failure of a release valve. This study investigates the formal extension of the SDG method to the sensor configuration of braking system, as well as the adaptation supported by the effect-function method.

关键词： fault diagnosis subway braking system signed directed graph sensor set optimization.

Position Control Optimization of Aerodynamic Brake Device for High-speed Trains

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Chinese Journal of Mechanical Engineering 2014年第2期27卷 287-295页

作者： ZUO Jianyong LUO Zhuojun chen zhongkai Institute of Railway and Urban Mass Transit Tongji University

The aerodynamic braking is a clean and non-adhesion braking, and can be used to provide extra braking force during high-speed emergency braking. The research of aerodynamic braking has attracted more and more attentions in recent years. However, most researchers in this field focus on aerodynamic effects and seldom on issues of position control of the aerodynamic braking board. The purpose of this paper is to explore position control optimization of the braking board in an aerodynamic braking prototype. The mathematical models of the hydraulic drive unit in the aerodynamic braking system are analyzed in detail, and the simulation models are established. Three control functions--constant, linear, and quadratic--are explored. Two kinds of criteria, including the position steady-state error and the acceleration of the piston rod, are used to evaluate system performance. Simulation results show that the position steady state-error is reduced from around 12-2 mm by applying a linear instead of a constant function, while the acceleration is reduced from 25,71-3.70 m/s2 with a quadratic control function. Use of the quadratic control function is shown to improve system performance. Experimental results obtained by measuring the position response of the piston rod on a test-bench also suggest a reduced position error and smooth movement of the piston rod. This implies that the acceleration is smaller when using the quadratic function, thus verifying the effectiveness of control schemes to improve to system performance. This paper proposes an effective and easily implemented control scheme that improves the position response of hydraulic cylinders during position control.

关键词： high-speed train aerodynamic brake hydraulic position control optimization.

Percutaneous closure of left internal mammary artery-to-pulmonary artery fistula using the domestic vascular plug:a case report

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Journal of Medical Colleges of PLA(China) 2010年第4期25卷 247-251页

作者： chen Shaoping Wang zhongkai Zhao Xianxian Qin Yongwen Department of Cardiology Changhai Hospital Second Military Medical University Shanghai 200433 China

A 55-year-old man was admitted for transcatheter closure because of pulmonary arteriovenous fistula by magnetic resonance angiography （MRA）. He had a history of occasional chest pain more than one year. Angiography didn＇t reveal significant stenosis at coronary artery. The patient was found a continuous grade 2/6 murmur over the left upper parastenal area one month ago. Chest MRA revealed a possible left superior pulmonary arteriovenous fistula. For diagnosis and localization of the fistula, aortography and selective angiography of the intemal mammary artery was performed and presented a left internal mammary artery-to-pulmonary artery fistula. The fistula was successfully closed using an 12 mm domestic vascular plug. Chest MRA showed that the fistula disappeared at two-month follow-up

关键词： Intemal mammary artery-to-pulmonary artery fistula Transcatheter closure Vascular plug

基于高光谱数据波段选择的茅洲河悬浮物浓度反演

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激光与光电子学进展 2021年第20期58卷 27-35页

作者：陈仲锴厉小润赵辽英浙江大学电气工程学院浙江杭州310027 杭州电子科技大学计算机应用技术研究所浙江杭州310018

针对基于高光谱数据的悬浮物浓度反演问题,提出一种利用预训练神经网络(PNN)进行有监督波段选择的方法,并使用随机森林和神经网络建立悬浮物浓度反演模型。PNN算法需进行多次重复实验以获得低噪声且充分的波段重要性表达,在每次实验时... 详细信息

针对基于高光谱数据的悬浮物浓度反演问题,提出一种利用预训练神经网络(PNN)进行有监督波段选择的方法,并使用随机森林和神经网络建立悬浮物浓度反演模型。PNN算法需进行多次重复实验以获得低噪声且充分的波段重要性表达,在每次实验时选取适当数量的波段作为神经网络输入数据的特征,训练一个神经网络,并利用最后一期训练时第一层权重的L1范数、L2范数和ReLU(Rectified Linear Unit)函数来表示波段的重要性。实验结果表明,相比其他常用的波段选择算法,使用L1范数、L2范数的PNN算法能够得到信息量更大的波段集合,且其用于悬浮物浓度反演时,能够获得更优的效果。

关键词：大气光学高光谱数据波段选择预训练神经网络悬浮物浓度反演

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积极推进高校档案信息化建设刍议

图书馆论坛 2004年第3期24卷 115-116,124页

作者：陈艳欢仲恺农业技术学院办公室广东广州510225

高校档案应尽快采用现代化手段进行管理 ,积极推进高校档案信息化建设是高校档案工作适应社会信息化的必然趋势。作者为此提出了实现高校档案信息化管理应采取的主要措施和对策。

关键词：高校档案管理信息化建设档案信息资源档案信息服务档案员素质

基于工作流技术的企业工作流程自动化系统的实现与研究

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微型电脑应用 2013年第12期29卷 19-22页

作者：陈中凯上海交通大学携程旅游信息技术(上海)有限公司

介绍了企业在业务和管理中面临的问题以及企业在业务流程自动化方面的需求,对工作流技术的发展概况与现状进行介绍,并对采用的工作流技术进行了研究。其次,通过对企业自身业务、管理的调研以及需求分析,对基于工作流技术的企业工作流程... 详细信息

介绍了企业在业务和管理中面临的问题以及企业在业务流程自动化方面的需求,对工作流技术的发展概况与现状进行介绍,并对采用的工作流技术进行了研究。其次,通过对企业自身业务、管理的调研以及需求分析,对基于工作流技术的企业工作流程自动化系统的功能逻辑结构进行了设计,并制订了本系统需要实现的业务流程,对整个系统的功能模块进行了划分。最后,对本系统在实际应用中起到的作用以及意义做了总结。

关键词：工作流企业工作流程自动化

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肾衰竭患者血液净化治疗的护理探讨

继续医学教育 2019年第11期33卷 77-78页

作者：陈忠凯天津市第一中心医院肾内科血透室

目的探讨优质护理服务在肾衰竭患者血液净化治疗中的应用效果。方法选取医院收治的72例肾衰竭患者,给予血液净化治疗,随机分为两组,对照组用常规护理,观察组用优质护理,比较两组干预情况。结果观察组焦虑情绪和抑郁较低(P<0.05);两组血... 详细信息

目的探讨优质护理服务在肾衰竭患者血液净化治疗中的应用效果。方法选取医院收治的72例肾衰竭患者,给予血液净化治疗,随机分为两组,对照组用常规护理,观察组用优质护理,比较两组干预情况。结果观察组焦虑情绪和抑郁较低(P<0.05);两组血尿素氮、血肌酐水平数值有所降低,并且观察组降低较多(P<0.05)。结论优质护理服务在肾衰竭患者血液净化治疗中的应用效果显著,能稳定患者情绪,降低患者血尿素氮、血肌酐水平。

关键词：优质护理服务肾衰竭常规护理血液净化应用效果

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超高层项目施工成本控制

福建建筑 2014年第8期 74-76页

作者：陈忠凯福建六建集团有限公司福建福州350001

主要介绍超高层项目施工成本控制的特点及方法,文章以某超高层项目为例,结合工程实际,主要从商务合同、生产进度、技术方案三个方面分别进行了介绍,并针对所采取的措施进行实例说明,具有一定参考价值。

关键词：超高层施工成本商务合同生产进度技术方案

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人工表面等离激元波导及天线若干进展

无线电工程 2022年第2期52卷 200-208页

作者：叶龙芳王正一陈仲凯安国腾厦门大学电子科学与技术学院电磁声学研究院福建厦门361005 东南大学毫米波国家重点实验室江苏南京210096

电磁波的传输和调控是电子学领域的一个研究热点,人工表面等离激元是一项通过在金属表面人工设计亚波长周期结构实现有效控制微波与太赫兹波传输的新技术。近年来,人工表面等离激元波导、电路与天线研究方面已取显著成果,为其在微波与... 详细信息

电磁波的传输和调控是电子学领域的一个研究热点,人工表面等离激元是一项通过在金属表面人工设计亚波长周期结构实现有效控制微波与太赫兹波传输的新技术。近年来,人工表面等离激元波导、电路与天线研究方面已取显著成果,为其在微波与太赫兹集成电路与系统中的应用奠定了基础。鉴于人工表面等离激元技术的重要应用前景,文章简要综述了人工表面等离激元波导、滤波器、频扫漏波天线以及涡旋波天线的若干最新研究进展,为新型人工表面等离激元波导与天线的开发及应用提供了参考。

关键词：人工表面等离激元波导滤波器频扫漏波天线涡旋波天线

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