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Frontiers in high entropy alloys and high entropy functional materials

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Rare Metals 2024年第10期43卷 4639-4776页

作者： Wen-tao Zhang Wen Huang Fu-Jie Yu Qi Zhao Xin-Dong Zhu tao Feng Yao Jiang Xiao-Ming {2. Xue-Fei Miao He Zhu Si Lan Xue-Qian Wang Bao-Long Shen Zhe Jia Feng-Qi Zhang Wei Wang Qi {2.u yang Ren Xun-{2. Wang Xiao-Ya Cui Xiao-yang Wang Ya-Nan Chen Bing-Bing Fan Meng-Ru {2. Qi-Long gao Jia-Ming Guo Zeng-Bao Jiao Zhi-Min Guo Yu-Ping Zhao Qian Yu Rui Huang {2.ng-Kun Zhang Yi-Ping Lu Xu-Bo {2. Huai-Jun {2.n Yan Ma Wei-Ming yang Zhi-Hua Shen Hai-Yan He Yong-Gang Sun Yong-Jiang Huang De-Zhuang Wang Qing-Feng {2.u Fei-yang Wang Hui {2.u Hong-Hui Wu {2.-Qiang Wang yang Lu Nan Wang Tian-{2. Wang Wei-Bing {2.ao Yi-Han Wang Yuan Wu Yu-Zhen Yin Jie Pan Yi Zhang Qing Wang Jian-yang Zhang tao yang Yasir Sohail Jin-Yu Zhang Hua Ji Qiang {2. Wei-Di {2.u Zhi-Gang Chen Xiong-Jun {2.u Wen Ma {2.ang Mao Zhen-Duo Wu School of Materials Science and Engineering Nanjing University of Science and Technology Jiangsu key laboratory for Advanced Metal{2.c Materials School of Materials Science and Engineering Southeast University Department of Physics City University of Hong Kong School of Materials Science and Engineering Tianjin University School of Physics and Microelectronics Zhengzhou University Department of Mechanical Engineering Research Institute for Advanced Manufacturing The Hong Kong Polytechnic University Center of Electron Microscopy and state key {2. of Silicon Materials School of Materials Science and Engineering Zhejiang University key laboratory of So{2.dification control and Digital Preparation Technology ({2.aoning Province) School of Materials Science and Engineering Dalian University of Technology Institute of Advanced Wear & Corrosion Resistance and Functional Materials Jinan University School of Mechanics and Civil Engineering China University of Mining and Technology School of Physical Sciences Great Bay University School of Materials Science andEngineering Harbin Institute of Technology state key {2. of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University beijing Advanced Innovation Center for Materials Genome Engineering Research Institute for Carbon Neutrality University of Science and Technology Beijing Department of Mechanical Engineering The University of Hong Kong School of Computing Macquarie University key laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic Engineering Shenzhen University state key {2. for Advanced Metals and Materials University of Science and Technology Beijing state key {2. of Materials Processing and Die & Mould Technology School of Materials Science and Engineering Huazhong University of Science and Technology Institute of materials Shanghai University Department of Materials Science and Engineering C

Owing to their exceptional properties, high-entropy alloys(HEAs) and high-entropy materials have emerged as promising research areas and shown diverse applications. Here,the recent advances in the field are comprehensively reviewed,organized into five sections. The first section introduces the background of HEAs, covering their definition, significance,application prospects, basic properties, design principles, and microstructure. The subsequent section focuses on cutting-edge high-entropy structural materials, highlighting developments such as nanostructured alloys, grain boundary engineering,eutectic systems, cryogenic alloys, thin films, micro-nano-lattice structures, additive manufacturing, high entropy metallic glasses, nano-precipitate strengthened alloys, composition modulation, alloy fibers, and refractory systems. In the following section, the emphasis shifts to functional materials, exploring HEAs as catalysts, magneto-caloric materials, corrosion-resistant alloys, radiation-resistant alloys, hydrogen storage systems, and materials for biomedicine. Additionally, the review encompasses functional high-entropy materials outside the realm of alloys, including thermoelectric, quantum dots, nanooxide catalysts, energy storage materials, negative thermal expansion ceramics,and high-entropy wave absorption materials. The paper concludes with an outlook, discussing future directions and potential growth areas in the field. Through this comprehensive review,researchers, engineers, and scientists may gain valuable insights into the recent progress and opportunities for further exploration in the exciting domains of high-entropy alloys and functional materials.

关键词： Cutting-edge structural materials Cutting-edgefunctional materials High entropy alloys

基于OpenStack的高可用城轨云平台:设计、实现与可用性分析

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铁道学报 2024年第2期46卷 94-104页

作者：朱力李子恒唐涛王悉北京交通大学轨道交通信号控制与安全国家重点实验室北京100044

轨道交通系统对于可靠性具有特殊要求,构建高可用轨道交通私有云计算平台,已成为城轨交通的热门研究领域。设计并实现高可用云管系统与高可用云上虚拟机,能有力推动更多的轨道交通业务向云平台迁移,提升资源利用率。首先,介绍轨道交通... 详细信息

轨道交通系统对于可靠性具有特殊要求,构建高可用轨道交通私有云计算平台,已成为城轨交通的热门研究领域。设计并实现高可用云管系统与高可用云上虚拟机,能有力推动更多的轨道交通业务向云平台迁移,提升资源利用率。首先,介绍轨道交通的云计算建设概况及云平台容错方法;其次,详细描述利用开源OpenStack技术,实现高可用云管平台与高可用虚拟机的方法,利用故障树工具分析云管系统与虚机的失效模式之后,用马尔科夫过程对云管系统与虚机的可靠性进行建模分析;最后,利用设计的高可用云平台,部署完整的基于通信的列车控制系统中的地面业务,并对虚拟机两项可用性的关键指标进行测试,根据测试结果,获得模型的参数,进而计算得到整个私有云计算平台的可用性指标。本研究将为城市轨道交通的高可用云计算平台建设提供有力的理论基础与实践经验。

关键词：城市轨道交通云计算 OpenStack 虚拟机高可用可靠性

Numerical simulation of predicting and reducing solid particle erosion of solid-liquid two-phase flow in a choke

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Petroleum Science 2009年第1期6卷 91-97页

作者： li Guomei Wang Yueshe He Renyang Cao Xuewen lin Changzhi Meng tao state key {2. of Multiphase Flow in Power Engineering Xi＇an Jiaotong University Xi＇an Shaanxi 710049 China china Special Equipment Inspection and Research Institute Beijing 100013 China School of Transport ＆ Storage and Civil Engineering China University of Petroleum Qingdao Shandong 266555 China Petroleum Exploration and Production Research Institute Sinopec Beijing 100083 China

Chokes are one of the most important components of downhole flow-control equipment. The particle erosion mathematical model, which considers particle-particle interaction, was established and used to simulate solid particle movement as well as particle erosion characteristics of the solid-liquid two-phase flow in a choke. The corresponding erosion reduction approach by setting ribs on the inner wall of the choke was advanced. This mathematical model includes three parts： the flow field simulation of the continuous carrier fluid by an Eulerian approach, the particle interaction simulation using the discrete particle hard sphere model by a Lagrangian approach and calculation of erosion rate using semiempirical correlations. The results show that particles accumulated in a narrow region from inlet to outlet of the choke and the dominating factor affecting particle motion is the fluid drag force. As a result, the optimization of rib geometrical parameters indicates that good anti-erosion performance can be achieved by four ribs, each of them with a height （H） of 3 mm and a width （B） of 5 mm equaling the interval between ribs （L）.

关键词： Solid-liquid two-phase flow discrete particle hard sphere model choke erosion rate antierosion numerical simulation

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智慧高速铁路运行控制系统发展趋势综述

铁道学报 2024年第1期46卷 1-12页

作者：余祖俊唐涛李开成宿帅朱力强北京交通大学先进轨道交通自主运行全国重点实验室北京100044 北京交通大学轨道交通运行控制系统国家工程研究中心北京100044 北京交通大学智慧高铁系统前沿科学中心北京100044 北京交通大学机械与电子控制工程学院北京100044

在保障安全的前提下,高速铁路运行控制系统进一步结合现代感知、控制、通信以及人工智能技术实现智慧化,是未来高速铁路发展的前沿方向。分析目前高速铁路运营中仍存在异物侵限造成安全事故、突发事件导致列车延误、运力与运量不匹配等... 详细信息

在保障安全的前提下,高速铁路运行控制系统进一步结合现代感知、控制、通信以及人工智能技术实现智慧化,是未来高速铁路发展的前沿方向。分析目前高速铁路运营中仍存在异物侵限造成安全事故、突发事件导致列车延误、运力与运量不匹配等问题,提出高速铁路运行控制系统的智能化、智慧化是解决上述问题的重要手段,是保持和提升我国高速铁路技术整体竞争力的核心组成部分。新时期的智慧高速铁路运行控制系统以实现列车(群)全天候全无人自主追踪运行控制为目标,主要包括移动闭塞、列车运行净空感知、列车状态智能监测、列车自主追踪、智能调度指挥、车-地动态自组网通信等关键技术。结合新一代使能技术,研究高速铁路运行控制智能技术的应用及其发展趋势,对我国智慧高速铁路的发展具有参考价值。

关键词：智慧高速铁路运行控制平稳追踪控制智能感知车-地自组网

基于传染病和网络流模型分析APT攻击对列车控制系统的影响

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铁道学报 2024年第4期46卷 119-129页

作者：赵骏逸唐涛步兵李其昌王晓轩北京交通大学轨道交通控制与安全国家重点实验室北京100044 中国铁道科学研究院集团有限公司通信信号研究所北京100081

高级可持续威胁(APT)是目前工业控制系统面临的主要威胁之一。APT攻击利用计算机设备漏洞入侵列车控制网络,感染并且扩散到网络中的其他设备,影响系统正常运行,因此评价APT攻击对列车控制系统的影响非常必要。提出一种基于传染病模型和... 详细信息

高级可持续威胁(APT)是目前工业控制系统面临的主要威胁之一。APT攻击利用计算机设备漏洞入侵列车控制网络,感染并且扩散到网络中的其他设备,影响系统正常运行,因此评价APT攻击对列车控制系统的影响非常必要。提出一种基于传染病模型和网络流理论结合的APT攻击影响分析方法。首先,分析在APT攻击的不同阶段设备节点状态之间的转化规则,结合传染病理论建立APT攻击传播模型,研究攻击过程中的节点状态变化趋势;其次,把设备节点的状态变化融入网络流模型中,研究APT攻击过程中设备节点状态变化对列车控制网络中列车移动授权信息流的影响;最后,结合列车控制系统的信息物理耦合关系,分析APT攻击对列控系统整体性能的影响。仿真实验展现了APT攻击过程中节点状态变化的趋势,验证该方法在分析APT病毒软件在列车控制网络中的传播过程对列车控制系统整体性能影响的有效性,为管理者制定防御方案提供依据,提升列车控制系统信息安全水平。

关键词：高级可持续威胁网络流理论传染病模型列车控制系统攻击影响分析

Formal verification of safety protocol in train control system

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Science china(Technological Sciences) 2011年第11期54卷 3078-3090页

作者： ZHANG Yan tang tao {2. MERA Jose Manuel ZHU li ZHAO lin XU TianHua state key {2. of rail traffic control and safety Beijing Jiaotong University Beijing 100044 China railway Technologies Research Centre Universidad Politecnica de Madrid Madrid 228006 Spain

In order to satisfy the safety-critical requirements,the train control system(TCS) often employs a layered safety communication protocol to provide reliable ***,both description and verification of the safety protocols may be formidable due to the system *** this paper,interface automata(IA) are used to describe the safety service interface behaviors of safety communication protocol.A formal verification method is proposed to describe the safety communication protocols using IA and translate IA model into PROMELA model so that the protocols can be verified by the model checker SPIN.A case study of using this method to describe and verify a safety communication protocol is *** verification results illustrate that the proposed method is effective to describe the safety protocols and verify deadlocks,livelocks and several mandatory consistency properties.A prototype of safety protocols is also developed based on the presented formally verifying method.

关键词： train control system safety communication protocol interface automata verification

基于LSTM-KF模型的高速列车群组追踪运行轨迹预测方法

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交通运输工程学报 2024年第3期24卷 296-310页

作者：张淼何仪娟杨博宇罗正伟卢万里唐涛李开成吕继东中国铁道科学研究院集团有限公司国家铁路智能运输系统工程技术中心北京100081 北京交通大学轨道交通运行控制系统国家工程研究中心北京100044 柏林洪堡大学计算机科学研究所柏林BE 104894 北京交通大学先进轨道交通自主运行全国重点实验室北京100044

为进一步缩小列车追踪距离以提高运力,研究了高速列车群组追踪运行轨迹预测问题;考虑长短期记忆网络(LSTM)模型处理序列数据的优势和卡尔曼滤波(KF)模型噪声处理的能力,提出了一种新型列车轨迹预测LSTM-KF模型;使用列车运行的历史数据进... 详细信息

为进一步缩小列车追踪距离以提高运力,研究了高速列车群组追踪运行轨迹预测问题;考虑长短期记忆网络(LSTM)模型处理序列数据的优势和卡尔曼滤波(KF)模型噪声处理的能力,提出了一种新型列车轨迹预测LSTM-KF模型;使用列车运行的历史数据进行LSTM模型训练,生成了列车轨迹预测曲线;KF模型结合预测结果和动力学机理,更正了计算结果,使LSTM模型预测的列车轨迹变得平滑;依托于高铁列控系统仿真测试平台的标准线路数据进行了仿真验证。仿真结果表明:在巡航工况下,30个预测步长后,LSTM-KF、LSTM和循环神经网络(RNN)模型的位置预测误差分别为78、798和911 m,速度相对真实值的预测误差分别为1、2.和1 m·s^(-1),LSTM-KF模型的位置均方根误差(RMSE)分别为LSTM和RNN的7%和15%,LSTM-KF模型的速度RMSE分别为LSTM和RNN的14%和30%;在加速工况下,3个模型的位置预测误差均值分别为94、2.4和2.91 m,速度预测误差均值分别为0.09、10.05和2.74 m·s^(-1);在减速工况下,3个模型的位置预测误差均值分别为1181、4135和4079 m,速度预测误差均值分别为1.14、6.01和13.52.m·s^(-1)。可见,LSTM-KF模型在不同运行工况下均能显著提升预测精度,能够有效生成长时域数据序列,为高速列车群组追踪运行提供决策。

关键词：高速列车群组追踪运行车-车通信轨迹预测长短期记忆网络卡尔曼滤波

traffic Modelling for Moving-Block Train {2. System

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Communications in Theoretical Physics 2007年第4期47卷 601-606页

作者： tang tao {2. Ke-Ping state key {2. of rail traffic control and safety Beijing Jiaotong University Beijing 100044 China

This paper presents a new cellular automaton （CA） model for train control system simulation. In the proposed CA model, the driver reactions to train movements are captured by some updated rules. The space-time diagram of traffic flow and the trajectory of train movement is used to obtain insight into the characteristic behavior of {2.way traffic flow. A number of simulation results demonstrate that the proposed CA model can be successfully used for the simulations of {2.way traffic. Not only the characteristic behavior of {2.way traffic flow can be reproduced, but also the simulation values of the minimum time headway are close to the theoretical values.

关键词： cellular automaton traffic flow moving-block system

Weight sequential log-likelihood ratio detect algorithm with malicious users removing

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The Journal of china Universities of Posts and Telecommunications 2013年第2期20卷 60-65页

作者： ZHAO Jun-hui li Fei yang {2. state key {2. of rail traffic control and safety Beijing Jiaotong University key laboratory of Wireless Sensor Network & Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences

Due to the openness of the cognitive radio network, spectrum sensing data falsification （SSDF） can attack the spectrum sensing easily, while there is no effective algorithm proposed in current research work, so this paper introduces the malicious users removing to the weight sequential probability radio test （WSPRT）. The terminals＇ weight is weighted by the accuracy of their spectrum sensing information, which can also be used to detect the malicious user. If one terminal owns a low weight, it can be treated as malicious user, and should be removed from the aggregation center. Simulation results show that the improved WSPRT can achieve higher performance compared with the other two conventional sequential detection methods under different number of malicious users.

关键词： cognitive radio cooperative spectrum sensing data falsification attack weight sequential log-likelihood ratio detect