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高速履带车辆横摆运动响应特性分析与试验验证

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兵工学报 2024年第4期45卷 1094-1107页

作者：袁艺盖江涛曾根周广明李训明马长军中国北方车辆研究所北京100072

为研究高速履带车辆操纵特性,奠定高速电驱动履带车辆的操纵稳定性评价及控制的基础,建立了高速履带车辆非线性转向动力学模型及2自由度线性转向动力学模型,并对模型进行试验验证。利用2自由度线性模型推导了高速履带车辆横摆运动传递函... 详细信息

为研究高速履带车辆操纵特性,奠定高速电驱动履带车辆的操纵稳定性评价及控制的基础,建立了高速履带车辆非线性转向动力学模型及2自由度线性转向动力学模型,并对模型进行试验验证。利用2自由度线性模型推导了高速履带车辆横摆运动传递函数,基于此进行了高速履带车辆横摆运动时域和频域响应特性分析,提出履带车辆稳态横摆角速度增益及临界阻尼车速的定义。研究结果表明:履带车辆稳态横摆角速度增益均小于1,履带车辆具有不足转向特性;履带车辆系统阻尼比在1左右;当车速小于临界阻尼车速时,车辆系统为过阻尼系统,横摆角速度响应的上升时间在0.2 s内;当车速等于临界阻尼车速时,车辆系统为临界阻尼系统,横摆角速度响应的上升时间大于10 s;当车速大于临界阻尼车速时,车辆系统为欠阻尼系统,横摆角速度响应的上升时间迅速减小至2~3 s。

关键词：高速履带车辆操纵特性横摆运动瞬态响应频率响应

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A weighted LS-SVM approach for the identification of a class of nonlinear inverse systems

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Science in China(Series F) 2009年第5期52卷 770-779页

作者： SUN ChangYin MU ChaoXu li xunming School of Automation Southeast University Nanjing 210096 China College of Electrical Engineering Hohai University Nanjing 210098 China

In this paper, a weighted least square support vector machine algorithm for identification is proposed based on the T-S model. The method adopts fuzzy c-means clustering to identify the structure. Based on clustering, the original input/output space is divided into several subspaces and submodels are identified by least square support vector machine （LS-SVM）. Then, a regression model is constructed by combining these submodels with a weighted mechanism. Furthermore we adopt the method to identify a class of inverse systems with immeasurable state variables. In the process of identification, an allied inverse system is constructed to obtain enough information for modeling. Simulation experiments show that the proposed method can identify the nonlinear allied inverse system effectively and provides satisfactory accuracy and good generalization.

关键词： subspaces weighted LS-SVM inverse system nonlinear modeling

基于牵引力-滑转率特性的高速电驱履带车辆行驶路面辨识方法研究

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车辆与动力技术 2024年第1期 15-21页

作者：侯云龙盖江涛袁艺曾根李训明马长军中国北方车辆研究所北京100072

电驱动高速履带车辆质量大、行驶速度快、行驶条件复杂,识别地面特性对其动力学控制具有重大意义.基于电驱动高速电驱履带车辆与地面之间的牵引力-滑转率特性,本文提出了一种利用长短期记忆神经网络(LSTM)进行路面识别的方法.通过采集... 详细信息

电驱动高速履带车辆质量大、行驶速度快、行驶条件复杂,识别地面特性对其动力学控制具有重大意义.基于电驱动高速电驱履带车辆与地面之间的牵引力-滑转率特性,本文提出了一种利用长短期记忆神经网络(LSTM)进行路面识别的方法.通过采集车辆行驶过程中的驱动电机转矩、转速信号及惯性测量单元得到的车辆纵向、横向加速度信号,记录并筛选出在一个滑转率变化过程中的牵引力-滑转率特征数据,通过LSTM神经网络,将特征数据归类,识别出当前行驶路面类型.该方法具有采集设备简单、信号易获得、算力要求较低等优点.仿真结果表明,该方法能够将车辆行驶路面准确归类于三种典型高、中、低附着路面.

关键词：履带滑转长短期记忆神经网络路面辨识

Modeling and Simulation of Power Coupling System in Hydraulic Hybrid City Bus

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Energy and Power Engineering 2014年第6期6卷 119-132页

作者： xunming li Jinyu Qu Wei Wei Xiangyu Tian School of Transport and Vehicle Engineering Shandong University of Technology Zibo China

In order to solve the coupling problem of power in Hydraulic Hybrid City Bus (HHB), a hydraulic hybrid power coupling system based on planetary gear transmission principle is proposed in this paper. The system consists of diesel engine, power coupler, hydraulic pump/motor, etc. The realizable operating modes of power coupling system are analyzed in this paper. Under coordination of clutches, the engine driven mode, hydraulic driven mode, hybrid driven mode, hydraulic engine-start mode and braking energy recovery mode are realizable. Based on Lagrange equation, kinetic analysis and kinematics analyses are presented. In addition, the simulation model of the power coupling system is proposed, which includes diesel engine model, power coupler model, hydraulic pump/motor model, etc. The example simulation analysis is proposed under the hybrid driven mode;the results show that the power coupling system proposed in this paper can realize power coupling of hydraulic hybrid city bus. Compared with traditional city bus, the hydraulic hybrid city bus can choose small-displacement engine so as to improve fuel economy and dynamic property.

关键词： HHB Power Coupling System Planetary Gear Trans Hydraulic Starting

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基于物理意义的示功图凡尔开闭点精确提取

石油勘探与开发 2011年第1期38卷 109-115页

作者：梁华李训铭河海大学能源与电气学院

凡尔开、闭点的提取是抽油井示功图识别与量化分析的基础,对抽油井故障诊断、功图量油等具有重要作用。根据有杆抽油泵的工作原理和凡尔开、闭点的物理意义,对地面示功图上凡尔开、闭点位置进行了理论分析,提出了一种精确提取地面示功... 详细信息

凡尔开、闭点的提取是抽油井示功图识别与量化分析的基础,对抽油井故障诊断、功图量油等具有重要作用。根据有杆抽油泵的工作原理和凡尔开、闭点的物理意义,对地面示功图上凡尔开、闭点位置进行了理论分析,提出了一种精确提取地面示功图上凡尔开、闭点的方法。在位移-时间曲线上确定上、下死点后,对载荷-时间曲线进行分区、去噪(平滑去噪、拟合去噪、迭代去噪)后,直接采用穷举比较法寻找最优解,从而确定固定凡尔和游动凡尔打开点(B点、D点);采用相同方法再确定游动凡尔和固定凡尔的关闭点(A点、C点)。编制了相应的软件,并利用1 000多个算例进行验证(包括多种故障算例),结果表明该方法能精确确定示功图上凡尔开、闭点位置。

关键词：抽油井示功图凡尔开闭点物理意义分区去噪

Direct Ischemic Postconditioning Following Stroke Thrombectomy:A Promising Therapy for Reperfusion Injury

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Neuroscience Bulletin 2024年第7期40卷 1017-1020页

作者： Jing Wang Lu Yang Longfei Wu Sijie li Changhong Ren Yuchuan Ding Ming Wei xunming Ji Wenbo Zhao Department of Neurology Xuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Emergency Xuanwu HospitalCapital Medical UniversityBeijing 100053China Beijing Key Laboratory of Hypoxic Conditioning Translational Medicine Xuanwu HospitalCapital Medical UniversityBeijing 100053China Department of Neurosurgery Wayne State University School of MedicineDetroitMI48201USA Beijing Institute for Brain Disorders Capital Medical UniversityBeijing 100069China Department of Neurosurgery Tianjin Huanhu HospitalTianjin 300222China Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijing 100053China

Recanalization of occluded vessels and timely reperfusion are the primary therapies for acute ischemic stroke(AIS),with endovascular thrombectomy proven as the most effective therapy for large-vessel recanalization and improved outcomes of AIS ***,despite a high recanalization rate of 90% or even higher,the rate of 3-month functional independence is approximately 50%,while mortality remains around 15%[1].

关键词： mortality acute Therapy

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基于NS2的改进队列管理算法及其实现

电力自动化设备 2008年第1期28卷 90-93页

作者：胡勇李训铭高莉莎南京供电公司江苏南京210000 河海大学电气工程学院江苏南京210098

主动队列管理是网络拥塞控制的重要控制机制,其好坏关系到整体网络性能的优劣。传统的PID控制器结构简单,性能良好,但在过程中参数固定。由于神经元的固有优点,它能够有效克服PID控制器参数难以整定和面对非线性系统难以处理等缺陷。设... 详细信息

主动队列管理是网络拥塞控制的重要控制机制,其好坏关系到整体网络性能的优劣。传统的PID控制器结构简单,性能良好,但在过程中参数固定。由于神经元的固有优点,它能够有效克服PID控制器参数难以整定和面对非线性系统难以处理等缺陷。设计了单神经元自适应PID控制器。从2个方面进行了分析和验证:针对TCP拥塞避免的动力学模型,以控制理论为指导,在Matlab软件环境下,对传统的增量式PID算法和改进的单神经元自适应算法进行分析和仿真,利用队列长度和数据报丢失概率2个参数的性能优劣进行比较;脱离理论数学模型,采用NS软件中节点、链路和FTP业务源等网络元素搭建试验平台,将PI、PID和改进算法应用其中,通过观测队列长度变化和数据源链接数的改变,考察系统的稳定性和自适应性。仿真和实验充分说明改进的单神经元自适应PID控制器具有更好的稳定性、鲁棒性和自适应性。

关键词：主动队列管理单神经元自适应PID控制器动力学反馈系统

Decreased levels of phosphorylated synuclein in plasma are correlated with poststroke cognitive impairment

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Neural Regeneration Research 2025年第9期20卷 2598-2610页

作者： Yi Wang Yuning li Yakun Gu Wei Ma Yuying Guan Mengyuan Guo Qianqian Shao xunming Ji Jia liu Department of Clinical Laboratory Beijing Bo’ai HospitalChina Rehabilitation Research CenterCapital Medical UniversityBeijingChina Beijing Institute of Brain Disorders Laboratory of Brain DisordersMinistry of Science and TechnologyCollaborative Innovation Center for Brain DisordersBeijing Advanced Innovation Center for Big Data-based Precision MedicineCapital Medical UniversityBeijingChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina

Poststro ke cognitive impairment is a major secondary effect of ischemic stroke in many patients;however,few options are available for the early diagnosis and treatment of this *** aims of this study were to(1)determine the specific relationship between hypoxic andα-synuclein during the occur of poststroke cognitive impairment and(2)assess whether the serum phosphorylatedα-synuclein level can be used as a biomarker for poststro ke cognitive *** found that the phosphorylatedα-synuclein level was significantly increased and showed pathological aggregation around the cerebral infa rct area in a mouse model of ischemic *** addition,neuronalα-synuclein phosphorylation and aggregation were observed in the brain tissue of mice subjected to chronic hypoxia,suggesting that hypoxia is the underlying cause ofα-synuclein-mediated pathology in the brains of mice with ischemic *** phosphorylatedα-synuclein levels in patients with ischemic stroke were significantly lower than those in healt hy subjects,and were positively correlated with cognition levels in patients with ischemic ***,a decrease in serum high-density lipoprotein levels in stroke patie nts was significantly correlated with a decrease in phosphorylatedα-synuclein *** ischemic stroke mice did not show significant cognitive impairment or disrupted lipid metabolism 14 days after injury,some of them exhibited decreased cognitive function and reduced phosphorylatedα-synuclein *** together,our results suggest that serum phosphorylatedα-synuclein is a potential biomarker for poststroke cognitive impairment.

关键词： biomarker high-density lipoprotein ischemic stroke phosphorylatedα-synuclein poststroke cognitive impairment

有理插值法求解TCR动态无功补偿触发角的探讨

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电力建设 2004年第12期25卷 12-14页

作者：李雪李训铭许胜河海大学电气工程学院南京市210098

TCR型动态无功补偿装置中触发控制角的计算精度影响无功补偿效果。以有理插值法作为晶闸管触发控制角的计算方法与多项式逼近法相比 ,计算量相当 ,但精度较高。以有理插值法求解TCR动态无功补偿触发角的计算方法是 :先求解基波电流有效... 详细信息

TCR型动态无功补偿装置中触发控制角的计算精度影响无功补偿效果。以有理插值法作为晶闸管触发控制角的计算方法与多项式逼近法相比 ,计算量相当 ,但精度较高。以有理插值法求解TCR动态无功补偿触发角的计算方法是 :先求解基波电流有效值与触发角关系 ,然后构造有理插值函数 ,在验证已构造有理插值函数的精度符合要求后 ,再根据触发角的关系公式求出触发角。

关键词：动态无功补偿触发控制角有理插值法