地铁机电系统综合集成平台的设计

通过借鉴国外地铁综合自动化方面的成功经验,结合广州地铁3号线主控系统的实际工程设计实践,对国内地铁综合自动化集成平台的设计思路进行系统性总结,以推动国内地铁自动化集成技术的应用和发展。     

船载海事卫星通信印刷四臂螺旋天线设计

为了解决四臂螺旋天线馈电结构复杂和网络损耗较大的问题,提出一种集成新型馈电网络结构的印刷四臂螺旋天线。通过大量的计算机电磁仿真分析发现天线的性能主要由螺旋臂的长度、螺旋的直径和螺旋节距的升角决定。基于此,制作了一款应用于船载海事卫星通信的印刷四臂螺旋天线并进行了测试。测试结果表明天线在系统要求的工作频带内驻波比小于1．4,增益高于2dB,半功率波瓣宽度达到140°,上半空间主要区域轴比小于3dB。测试结果与仿真结果具有较好的一致性。天线实际应用效果良好。     

电抗加载高频地波雷达天线阵设计方法研究

采用电抗加载的思想设计了小型偶极子二元天线阵,并利用矩量法验证了天线阵的高前后比与单向辐射特性。针对高频地波雷达的使用需求,以二元阵为子阵设计了小型平面接收天线阵和海岛共形接收天线阵。仿真实验结果表明,两型天线阵均能在一定范围的期望信号来波方向上形成窄波束,且具有较好的旁瓣抑止能力。相比之下,海岛共形天线阵以其占地面积较小,对天线阵架设限制要求低等优点,更适合于工程应用。文章进行的设计与分析对高频地波雷达天线阵的工程设计具有一定的指导意义。     

基于可重构技术的数字系统再生设计

为了适应数字系统再生设计的需要,设计了一个基于可重构模块的辅助学习系统,完成了对特定模块的功能复制。通过微指令跟踪的方法,获得了研究对象的全部接口数据。并通过软件方法对接口数据进行约简处理,使用VHDL语言编辑配置文件,配置可重构模块。设计了一个实用的并行接口电路板,完成了辅助学习系统的功能切换。最后通过对某型计算机的辅助运算模块的再生设计实例,验证了方法的有效性,并通过对比试验完成了对故障板的故障诊断任务。     

裂纹的扩展有限元数值模拟研究

扩展有限元方法中,结构的不连续模拟通过单位分解的方法对位移模式的局部富集来实现,这个技术可以使得裂纹的不连续性独立于结构的单元划分.阐述了富集函数的构造、支配方程的建立、数值积分方案及程序实现等.对于线弹性体裂纹的模拟.通过一个跳跃函数和二维裂纹尖端位移渐进场来考虑裂纹的不连续性和奇异性.通过编制扩展有限元程序,模拟了各向同性介质中的二维裂纹.最后通过算例的模拟结果证明了该方法的精确性和实用性.     

吊滚结合的重大件码头装卸工艺设计

重大件的上、下岸工艺分为吊装和滚装2种。结合工程实例,根据某码头腹地重大件运量大、种类多、质量和尺寸变化范围大的特点,设计吊滚结合的重大件装卸工艺,以实现2种工艺的优势互补,提高重大件码头的作业效率以及对货种的适应能力;分析探讨平面布置、工艺设计以及其中几个关键参数的确定;并通过码头通过能力的计算,验证工艺的可行性和效果,为类似工程的设计建设提供参考。     

高黎贡山铁路隧道彩云号TBM的创新性设计与应用

高黎贡山铁路隧道作为大瑞铁路的关键性控制工程,具有“三高四活跃”的地质特点,为应对TBM施工过程中可能遇到的断层破碎带、突泥涌水、岩爆等灾害,正洞TBM设计实行了变截面可抬升开挖技术,创新了前置式自动化混喷技术、隐藏式常态化超前钻探技术以及水岩一体超前预报技术。实践表明,在掘进过程中TBM的创新性设计发挥了显著作用,可为同类地质条件TBM设计与应用提供经验。     

模架一体化新型衬砌台车设计及应用技术研究

为解决传统的混凝土衬砌施工时边墙振捣安全性及其他工序车辆通行受阻等问题,以丽江至香格里拉铁路站前工程LXZQ-2标中义隧道工程为依托,通过对隧道混凝土衬砌施工工艺和台车结构进行系统分析和研究,确定单线铁路隧道模架一体化新型衬砌台车的设计方案和参数。该台车具有模架一体化技术以及新型便捷式振捣技术,并在中义隧道进行现场应用。结果表明： 1）该台车内部净空增大,装载机以及出碴车能够轻松通过台车底部,杜绝了磕碰等隐患; 2）关、拆模较旧台车提前2 h左右; 3）采用质量轻、42 V低电压新型振捣棒,安全性更高,同时借助于弹力卷筒、导向装置的作用可以大大降低工人振捣时的劳动强度。     

Pricing strategies for port competition and cooperation

This paper analyzes the effects of integration between two neighbor ports with a third port sharing the same overlapping hinterland. The merger (integrated port) can select either the price discrimination or uniform pricing strategy after integration. Our study reveals that port integration is always beneficial to the merger and the third port, but results in the reduction of consumer surplus and social welfare, regardless of the type of pricing strategy implemented. Further analysis shows that when the inland transportation cost to the ports is relatively low or sufficiently high, a better option is for the merger to adopt the price discrimination strategy. When port pollution is considered and has a relatively large impact, the integration of the two ports improves green social welfare for the region. This finding provides strong support for the ongoing port integration in China. In terms of pricing strategy, the uniform pricing strategy generates higher green social welfare when both inland transportation cost and pollution are relatively low, or both are significantly high. Otherwise, the price discrimination strategy generates the best result for the region.     

Traffic evacuation simulation based on multi-level driving decision model

Traffic evacuation is a critical task in disaster management. Planning its evacuation in advance requires taking many factors into consideration such as the destination shelter locations and numbers, the number of vehicles to clear, the traffic congestions as well as traffic road configurations. A traffic evacuation simulation tool can provide the emergency managers with the flexibility of exploring various scenarios for identifying more accurate model to plan their evacuation. This paper presents a traffic evacuation simulation system based on integrated multi-level driving-decision models which generate agents’ behavior in a unified framework. In this framework, each agent undergoes a Strategic, Cognitive, Tactical and Operational (SCTO) decision process, in order to make a driving decision. An agent’s actions are determined by a combination, on each process level, of various existing behavior models widely used in different driving simulation models. A wide spectrum of variability in each agent’s decision and driving behaviors, such as in pre-evacuation activities, in choice of route, and in the following or overtaking the car ahead, are represented in the SCTO decision process models to simulate various scenarios. We present the formal model for the agent and the multi-level decision models. A prototype simulation system that reflects the multi-level driving-decision process modeling is developed and implemented. Our SCTO framework is validated by comparing with MATSim tool, and the experimental results of evacuation simulation models are compared with the existing evacuation plan for densely populated Beijing, China in terms of various performance metrics. Our simulation system shows promising results to support emergency managers in designing and evaluating more realistic traffic evacuation plans with multi-level agent’s decision models that reflect different levels of individual variability of handling stress situations. The flexible combination of existing behavior and decision models can help generating the best evacuation plan to manage each crisis with unique characteristics, rather than resorting to a fixed evacuation plan.