工业以太网在城轨车辆中的应用研究

基于以太网技术的列车通信网络为研究对象,从列车通信网络架构设计及功能集成设计2方面进行了应用性研究。首先,对基于以太网的列车通信网络构建形式进行了探讨,并从不同维度对各种网络拓扑形式进行了可靠性分析;在此基础上,进一步讨论了多业务融合网络技术在城市轨道交通车辆中的实现形式;最后,通过具体的应用实例验证了文中所设计的适应多业务融合的列车以太网网络拓扑的可行性。实测表明,该网络系统模型稳定可靠,具有较强的网络兼容性以及良好的通信性能,能够有效提升网络控制系统应用效率。     

Network lifetime global optimization for multi-source and single-sink topology in wireless sensor networks

The multi-source and single-sink (MSSS) topology in wireless sensor networks (WSNs) is defined as a network topology, where all of nodes can gather, receive and transmit data to the sink. In energy-constrained WSNs with such a topology, the joint optimal design in the physical, medium access control (MAC) and network layers is considered for network lifetime maximization (NLM). The problem of integrating multi-layer information to compute NLM, which involves routing flow, link schedule and transmission power, is formulated as a non-linear optimization problem. Specially under time division multiple access (TDMA) scheme, this problem can be transformed into a convex optimization problem. To solve it analytically we make use of the property that local optimization is global optimization in convex problem. This allows us to exploit the Karush-Kuhn-Tucker (KKT) optimality conditions to solve it and obtain analytical solution expression, i.e., the globally optimal network lifetime (NL). NL is derived as a function of number of nodes, their initial energy and data rate arrived at them.Based on the analysis of analytical approach, it takes the influence of data rates, link access and routing method over NLM into account. Moreover, the globally optimal transmission schemes are achieved by solution set during analytical approach and applied to algorithms in TDMA-based WSNs aiming at NLM on OMNeT<++> to compare with other suboptimal schemes.     

基于SNMP的铁路信号监督系统网络拓扑发现方法

为了保障铁路信号集中监测系统运行的可靠性，设计一种基于SNMP、ICMP和端口扫描的网络拓扑关系发现方法，自动生成CSM网络设备拓扑图。通过C#语言编程实现并展示了应用该方法生成的网络拓扑图效果。通过本方法，能够快速、准确、全面地发现活动节点物理连接关系，有利于维护人员远程实时监测网络设备运行状态，便于设备故障的定位、分析与维护。     

锦州港企业内部网网络系统设计

设计了一个企业内部网的网络运行系统，介绍了系统的软件应用。该系统可靠性高、性能价格比好。     

汽车以太网技术发展现状与趋势探究

智能网联化已经成为当代汽车发展的重要主题,传统汽车网络通讯技术CAN,LIN等很难支撑汽车智能网联化的进一步发展,汽车以太网技术将在新一代汽车网络架构中承担重要角色。文章对汽车网络技术的发展进行了总结,对汽车以太网技术特点和现状进行了分析,阐明了汽车以太网技术的优势,研究了汽车以太网技术的发展趋势与主要挑战,并探讨了汽车以太网对新一代汽车网络架构的影响。     

基于云计算平台的船舶航行数据实时快速采集系统设计

为给船舶航行控制、运维等提供数据,设计基于云计算平台的船舶航行数据实时快速采集系统。该系统数据源模块利用数据采集装置采集船舶实时航行数据,通过接收机和广播信号将其传输到DDN网络模块内,该网络模块通过路由器、交换机等将船舶航行数据传输到服务模块内,该模块通过采集服务和其他服务内的单元执行数据采集、数据异常分析、告警以及采集远程控制等功能,并将数据采集、分析等结果传输到应用模块内,应用模块通过数据实时显示、数据查询等单元为用户提供数据采集与分析等结果。实验表明,该系统采集船舶航行数据较为精准,且采集数据的实时性较好。     

轨道交通冗余工业以太网设计分析

正1地铁冗余工业网络发展概况工业以太网由于具有与商用以太网截然不同的实时性和安全性方面的特质,在轨道交通领域得到越来越广泛的应用。其中冗余和自愈是网络体系架构的一个重要特点,它是在自动化对系统的可靠安全性、实时稳定要求背景下诞生的。实时性和安全性方面的要求已经把工业环形网络的拓扑结构应用到轨道交通多个系统传输网络平台,在ISCS、BAS、PSCADA、AFC、PIS等多个系统中     

Synchronization research of a modified time-delayed multi-agent network model

The synchronization of time-delayed multi-agent networks with connected and directed topology is studied. Based on the correlative work about the agent synchronization, a modified model is presented, in which each communication receiver is distributed a delay τ. In addition, a proportional term k is introduced to modulate the delay range and to guarantee the synchronization of each agent. Two new parameters mentioned above are only correlative to the network topology, and a theorem about their connections is derived by both frequency domain method and geometric method. Finally, the theoretical result is illustrated by numerical simulations. Foundation item: the National Natural Science Foundation of China (No. 70571017) and the Research Foundation from Provincial Education Department of Zhejiang of China (No. 20070928)     

LONWORKS网络技术及其应用

本文参考ECHELON的有关资料,结合我们应用LONWORKS技术的具体实践,探讨了LONWORKS与现场总线以及局域网的关系及其应用。     

现场总线技术在城市轻轨和地铁车辆控制系统中的应用

从轻轨车和地铁车辆的控制系统网络拓扑的结构上对多种现场总线进行了对比，并且介绍了各种现场总线的传输介质、通信速率、介质访问方式、数据交换方式、帧结构、差错控制方式等。