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Safety Mechanism Design and Verification of Safety Computer Parallel Program

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Chinese Journal of Electronics 2018年第6期27卷 1163-1169页

作者： ZHANG Yuzhuo HONG Chunhua cao yuan MA Lianchuan WEN Yinghong School of Electronic and Information Engineering Beijing Jiaotong University National Engineering Research Center of Rail Traffic Control System Beijing Jiaotong University

The extensive application of Commercial off-the-shelf(COTS) components into safety computers in train control systems has caused safety problems. Aiming at the parallel programs, a concurrent program safety management mechanism based on transactional memory is proposed. The proposed mechanism implements concurrent behaviors of the application in the safe policy. A verification framework based on invariant proof and parallel separation logic theory is designed and operating system operation semantics are given for mathematical reasoning and proving. An example of code execution process is demonstrated to explain the safety control process of concurrent safety mechanism. The results indicate that the program can meet the safety and reliability requirements of concurrent safety computer platforms.

关键词： Safety computer Parallel program Transactional memory Invariant proof Concurrent separation logic

Standard Analysis for Transfer Delay in CTCS-3

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Chinese Journal of Electronics 2017年第5期26卷 1057-1063页

作者： cao yuan MA Lianchuan XIAO Shuo ZHANG Xia XU Wei National Engineering Research Center of Rail Transportation Operation and Control System Beijing Jiaotong University State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Computer Sciences and Technology China University of Mining & Technology National Mobile Communications Research Lab. Southeast University

According to the standard for the GSM for railway(GSM-R) wireless systems in China train control system level 3(CTCS-3),the control data transfer delay should be no larger than 500 ms with greater than99% *** of both non-redundant networks and intercross redundant networks and cases of single Mobile terminals(MTs) and redundant MTs on one train are considered,and the corresponding vehicle-ground communication models,delay models,and fault models are *** simulation results confirm that the transfer delay can meet the standard requirements under all *** particular,the probability is greater than 99.996% for redundant MTs and networks,and the standard of transfer delay in CTCS-3 will be improved inevitably.

关键词： China train control system level 3(CTCS-3) GSM for railway(GSM-R) Data transfer delay Deterministic and stochastic petri net(DSPN)

Optimization of Information Interaction Protocols in Cooperative Vehicle-Infrastructure Systems

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Chinese Journal of Electronics 2018年第2期27卷 439-444页

作者： ZHANG Yuzhuo cao yuan WEN Yinghong LIANG Liang ZOU Feng School of Electronic and Information Engineering Beijing Jiaotong University Department of Electrochemical Telecom Engineering Design Research The Third Railway Survey and Design Institute Group Corporation

This research investigate the information interaction protocols for Cooperative vehicleinfrastructure systems(CVIS) safety-related services and optimizes them in three aspects. It puts forward a selfadaptive back-off algorithm. This algorithm considers retransmission times and network busy degree to choose a suitable contention window. A mathematical analysis model is developed to verify its performance ***, different scenario models of Vehicle ad hoc network(VANET) are simulated through the network simulation tool and the influences of different access modes on Quality of Service(Qo S) are investigated. The simulation results have verified the improvement of the proposed algorithm is obvious and RTS/CTS access mode can sacrifice slight delay for great improvement of packet lost rate when there are large amount of vehicle nodes.

关键词： Cooperative vehicle-infrastructure systems(CVIS) Information interaction Network simulation

基于网络药理学和分子对接探讨参苓白术散治疗代谢相关脂肪性肝病作用机制

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海峡药学 2024年第3期36卷 5-10页

作者：许淑梅钟草源程变巧福建中医药大学第二临床医学院福建福州350000 福州市第二医院福建福州350000

目的应用网络药理学方法和分子对接探讨参苓白术散治疗代谢相关脂肪性肝病的潜在作用机制。方法根据TCMSP数据库搜集中药活性成分及其作用靶点,GeneCards、Drugbank数据库搜集疾病靶点,借助Cytoscape 3.9.1软件预测关键活性成分及核心... 详细信息

目的应用网络药理学方法和分子对接探讨参苓白术散治疗代谢相关脂肪性肝病的潜在作用机制。方法根据TCMSP数据库搜集中药活性成分及其作用靶点,GeneCards、Drugbank数据库搜集疾病靶点,借助Cytoscape 3.9.1软件预测关键活性成分及核心靶点。交集靶点通过STRING数据库进行蛋白互作分析,Metascape数据库进行GO功能和KEGG通路富集分析,最后借助AutoDock Vina 1.1.2软件进行分子对接验证。结果筛得关键活性成分有槲皮素、豆甾醇、山柰酚、木犀草素、β-谷甾醇、7-甲氧基-2甲基异黄酮、柚皮素等,核心靶点有AKT1、TNF、IL6、TP53、VEGFA、IL1B、CASP3、ESR1、MAPK3、PTGS2,潜在作用靶点主要富集在P53、TNF、IL17、Th17细胞分化等信号通路。分子对接结果显示结合力均良好。结论参苓白术散治疗代谢相关脂肪性肝病具有多成分、多靶点、多通路的特点。

关键词：参苓白术散代谢相关脂肪性肝病网络药理学分子对接作用机制

Null subcarriers based Doppler scale estimation with polynomial interpolation for multicarrier communication over ultrawideband underwater acoustic channels

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1177-1183页

作者： Yang Chen Jingwei Yin Ling Zou Dan Yang yuan cao School of Information Science and Engineering Changzhou University College of Underwater Acoustic Engineering Harbin Engineering University School of Textile and Material Engineering Wuhan Textile University School of Electrical and Electronic Engineering Nanyang Technological University

This paper addresses the extremal problem of the null subcarriers based Doppler scale estimation in underwater acoustic （UWA） orthogonal frequency division multiplexing （OFDM） communication. The cost function constructed of the total energy of null subcarriers through discrete Fourier transform （DFT） is proposed. The frequencies of null subcarriers are identified from non-uniform Doppler shift at each tentative scaling factor. Then it is proved that the cost function can be fitted as a quadratic polynomial near the global minimum. An accurate Doppler scale estimation is achieved by the location of the global scarifying precision and increasing the computation minimum through polynomial interpolation, without complexity. A shallow water experiment is conducted to demonstrate the performance of the proposed method. Excellent performance results are obtained in ultrawideband UWA channels with a relative bandwidth of 67%, when the transmitter and the receiver are moving at a relative speed of 5 kn, which validates the proposed method.

关键词： underwater acoustic (UWA) communication orthogo-nal frequency division multiplexing (OFDM) Doppler scale estimation polynomial interpolation.

基于功率变换器的梯次利用电池系统均衡控制策略

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储能科学与技术 2024年第5期13卷 1635-1642页

作者：张大兴黄泽荣王祥东王延凯蔡冰子袁昊宇田明明袁英平曹原南方电网广东电网有限责任公司惠州供电局广东惠州516000 中南大学自动化学院湖南长沙410083

梯次利用是一种处理退役锂电池的经济高效的方法。但是在电池梯次利用过程中,存在不同新旧状态电池混用而导致的不均衡问题,会影响电池系统的安全稳定运行。本工作分析了梯次利用电池直接并联时,由于不均衡导致的电流环流以及系统容量... 详细信息

梯次利用是一种处理退役锂电池的经济高效的方法。但是在电池梯次利用过程中,存在不同新旧状态电池混用而导致的不均衡问题,会影响电池系统的安全稳定运行。本工作分析了梯次利用电池直接并联时,由于不均衡导致的电流环流以及系统容量利用率低的问题。为解决这一问题,本工作提出一种基于功率变换器的梯级电池并联系统结构及均衡控制算法。所提方法将每个电池模组和功率变换器相连组成一个功率模组,通过调节电压环路、电流环路、荷电环路的输出,分别控制每个电池模组的充放电电流,最终实现梯次利用电池均衡优化控制策略。本工作给出了系统控制策略的详细分析和实验结果讨论,以评估和验证所提均衡方法的有效性。实验测试表明,在使用相同健康程度电池、不同健康程度电池以及变负载等测试情况下,本工作所提梯次利用电池均衡控制策略都能够稳定、有效控制不同电池电流,保证电池之间的荷电参数均衡,提高了电池系统整体效率。本研究可以促进废旧电池的有效梯次利用,并为电池系统均衡控制提供新思路。通过实现电池的均衡利用,可以延长电池的使用寿命,降低系统故障风险,提高系统的可靠性和稳定性。

关键词：电池储能系统荷电参数电池均衡功率变换器电池梯次利用

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某院394例流感患儿流行病学特征及病原学分析

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广州医药 2024年第7期55卷 759-763,775页

作者：范明明曹原王利伟开封市疾病预防控制中心学校与儿少卫生科河南开封475000 开封市祥符区第一人民医院检验科河南开封475100

目的分析流行性感冒(流感)患儿的流行病学特征及病原学分布。方法纳入2020年3月—2023年2月在开封市祥符区第一人民医院确诊为流感的394例1~10岁患儿的咽拭子标本,通过实时荧光定量聚合酶链式反应完成流感病毒检测,分析此394例流感患... 详细信息

目的分析流行性感冒(流感)患儿的流行病学特征及病原学分布。方法纳入2020年3月—2023年2月在开封市祥符区第一人民医院确诊为流感的394例1~10岁患儿的咽拭子标本,通过实时荧光定量聚合酶链式反应完成流感病毒检测,分析此394例流感患儿感染的病毒类型及年龄、季节、性别、年份等分布情况。结果甲型H1N1流感病毒为本次研究检出占比最高的流感病毒,占36.04%;男女患儿之间的甲型H3、甲型H1N1、乙型BV、乙型BY流感病毒占比比较差异无统计学意义(P>0.05);春季及冬季流感患儿占比最多,分别为41.12%、35.53%,且不同季节之间的甲型H3、甲型H1N1、乙型BV、乙型BY流感病毒占比比较差异有统计学意义(P0.05);2020年流感患儿占比最高,为43.40%,后续依次为2022年的29.70%,2021年的26.90%;不同年份的冬季流感患儿占比比较差异有统计学意义(P0.05);各年甲型H3、甲型H1N1、乙型BV、乙型BY流感病毒占比比较差异无统计学意义(P>0.05)。结论年龄7~10岁的患儿为流感高危群体,且甲型流感为患儿主要感染类型,而甲型流感病毒多见于春、冬季,新型冠状病毒肺炎疫情期间防控政策变化对流感流行有影响,应加强春、冬季7~10岁年龄段患儿的甲流预防工作。

关键词：流行性感冒流行病学特征病原学分析儿童

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Vibration Signal-Based Fault Diagnosis of Railway Point Machines via Double-Scale CNN

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Chinese Journal of Electronics 2023年第5期32卷 972-981页

作者： CHEN Xiaohan HU Xiaoxi WEN Tao cao yuan The School of Electronic and Information Engineering Beijing Jiaotong University The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University The National Engineering Research Center of Rail Transportation Operation Control System Beijing Jiaotong University

In the railway transportation industry,fault diagnosis of railway point machines(RPMs) is *** operational vibration signals can reflect the condition of various faults in mechanical devices, vibration sensing and monitoring and more importantly, vibration signal-based fault diagnosis for RPMs have attracted the attention of scholars and engineers. Most vibration signalbased fault-diagnosis methods for RPMs rely on data collected using high-sampling-rate sensors and manual feature extraction, hence are costly and insufficiently *** overcome these shortcomings, we propose a doublescale wide first-layer kernel convolutional neural network(DS-WCNN) for RPMs fault diagnosis using inexpensive and low-sampling-rate vibration sensors. The proposed wide first-layer kernels, which extract features from vibration observations, are particularly suitable for lowsampling-rate signals. Meanwhile, the proposed doublescale structure improves accuracy and noise suppression by combining two types of timescale features. Sufficient experiments, including noise addition and comparison,were conducted to demonstrate the robustness and accuracy of the proposed algorithm.

关键词： Vibrations Fault diagnosis Transportation industry Feature extraction Rail transportation Robustness Convolutional neural networks

基于主从博弈的差异化建筑集群与微网协同优化调度方法

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电力系统及其自动化学报 2024年第3期36卷 1-11页

作者：郝志方安佳坤侯若松曹媛靳小龙董晓红国网河北省电力有限公司经济技术研究院石家庄050021 天津大学智能电网教育部重点实验室天津300072

为充分调动绝热性能差异化建筑的需求响应能力,本文提出基于主从博弈的差异化建筑集群与微网协同优化调度方法。首先,采用热阻-热容网络对建筑的热动态特性进行建模,并构建暖通系统的用能模型;其次,为充分发挥接入建筑的电动汽车的灵活... 详细信息

为充分调动绝热性能差异化建筑的需求响应能力,本文提出基于主从博弈的差异化建筑集群与微网协同优化调度方法。首先,采用热阻-热容网络对建筑的热动态特性进行建模,并构建暖通系统的用能模型;其次,为充分发挥接入建筑的电动汽车的灵活可调潜力,提出电动汽车到建筑集成系统的用能模型;然后,基于主从博弈提出微网与差异化建筑群的协同优化框架,并针对建筑群的差异化需求响应潜力提出定制化的电价方案;最后,通过算例验证了本文方法可根据建筑的差异化绝热性能灵活制定差异化的售电价格,从而充分挖掘建筑群差异化的需求响应能力。

关键词：微网建筑热动态特性电动汽车主从博弈差异化需求响应能力