地铁车辆段接触轨安全保障体系构建

研究深圳地铁3号线横岗双层车辆段接触轨区域安全保障体系的构建,从构建思路、构建原则以及体系架构等方面开展研究 系统介绍接触轨区域安全保障体系的内容,分析构建安全保障体系的意义,说明接触轨区域安全保障体系的建立对该技术在全国城市轨道交通系统中的安全实施与应用起到重要的指导作用.     

汽车导航用电子地图的高效路网模型

为了有效地描述实际道路网络，提高汽车导航系统的运行效率，建立了一种新的电子地图的路网模型。在分析了嵌入式系统特点的基础上，对路网的数据结构进行了简化。采用重整实体ID的方法，进一步提高了数据的处理效率。实践证明，该模型可以较好地表述实际的道路网络，结构精练，处理效率高，适合车载导航系统，特别是嵌入式车载导航系统的要求。     

海洋核动力平台电力系统设计概要

中国正在进行的海洋核动力平台国家示范工程项目,其电力系统设计存在着新的问题。本文以海洋核动力平台的需求为立足点,充分兼顾核电站的设计要求以及船舶入级的要求,归纳了适用于海洋核动力平台电力系统设计的要点,对海洋核动力平台的工程设计和新标准规范的制定具有较强的参考意义。     

Evaluating determinants of attractiveness and their cause-effect relationships for container ports in Taiwan: users’ perspectives

The attractiveness of ports is usually a pre-requisite and necessary condition for ports to achieve competitiveness, as well as the springboard to explore the competitive advantages of ports. To determine whether a port is competitive, it is necessary to explore whether it boasts certain factors that make the port attractive to users. The main purpose of this article is to apply the Analytic Hierarchy Process (AHP) method and the Decision Making Trial and Evaluation Laboratory (DEMATEL) technique to evaluate key determinants of attractiveness and their cause/effect relationships for container ports in Taiwan. The empirical results showed that: (1) Top six determinates of attractiveness for container ports are ‘ample cargo sources,’ ‘favorable port charges,’ ‘dense ship network and routes,’ ‘low transshipment costs,’ ‘efficient wharf operations,’ and ‘adequate wharfs and back-line land,’ respectively. (2) Among the above six determinants of attractiveness, ‘ample cargo sources’ is the cause determinant. Three determinants of port attractiveness, ‘favorable port charges,’ ‘dense ship network and routes,’ ‘low transshipment costs,’ which are the effect determinants. They are affected by the determinants of attractiveness of ‘ample cargo sources’. In addition, this study discusses the above findings and expects to provide the study results to Taiwan’s port authorities for reference.     

广西交通科技资源共享平台建设探讨

文章针对广西交通科技项目管理系统现状,分析了建设交通科技资源共享平台的必要性,阐述了交通科技资源共享平台建设的关键技术、创新点及主要内容,指出该共享平台的建设可改善和提高交通运输科技项目质量及监管水平。     

Hybrid process of fabricating high-quality micro wine-glass fused silica resonators

A new hybrid method, which combines improved glass-blown technology with wet etching, is reported to fabricate micro wine-glass resonators with high-quality fused silica. The optimum placement is compared to achieve the resonators with good shell shape. The typical shell diameter is about 4mm and its thickness covers from dozens to hundreds of micrometers. The etching rates in corrosion solutions with different ratios and at different thicknesses of hemispherical shells are studied. We also conclude how to precisely control the thickness. The corrosion solutions with different ratios of HF solution to NH₄F solution make the spherical shells rougher in different degrees. The best roughness is 0.581 nm in the 1: 8 ratio corrosion solution while the original roughness is 0.537 nm. This fact shows that the resonator remains atomically smooth surface. Based on the glassblowing spherical fused silica structure, the thickness of the resonator is effectively controlled by buffered oxide etch (BOE) technology according to the measured etching rate. The measured resonant frequency of the hemispherical shell at ambient pressure and room temperature is 1.75 kHz of rocking mode which is close to the simulated frequency. Using such a low-cost hybrid approach, we can fabricate high-quality microscale resonators in batch.     

肋骨侧向稳定性特征屈曲有限元分析

环肋圆柱壳通常在周向布置肋骨来提高其稳定性,在深水压力作用下,肋骨发生侧向失稳的可能性加大,进而影响环肋圆柱壳的整体稳定性。在理论分析的基础上,采用有限元法对环肋圆柱壳进行在静水压力和轴向压力作用下的特征屈曲分析,研究肋骨侧向失稳的屈曲特征,得到肋骨侧向失稳的判别方法,为工程设计提供参考。     

基于大型打桩船桩架的三维力学特性分析

应用国际广泛使用的大型通用结构有限元分析程序ALGOR对110m大型打桩船桩架进行了三维力学分析,该装备是国内最高并在海上施工的桩架,因此对各工况进行了详细的分析研究,并给出了合理的设计建议。对从事该领域设计施工者有一定指导作用。     

高频PWM波反射对电机端过电压的影响

本文采用波理论分析变频驱动系统中高频PWM波反射,采用MATLAB仿真软件搭建软件模型,分析变频器输出电压波形的上升下降时间、供电电缆的长度、供电电缆分布参数及系统负载大小对电机前端过电压产生的影响,总结出高频PWM波反射对电机端过电压的影响。     

AFC系统应用软件中采用成熟模块的探讨

AFC系统作为票务运营管理系统,其应用软件的功能是否完善,直接影响到票务收益的安全及售检票终端设备操作的方便性.本文对AFC系统的核心业务进行分析,比较了采用成熟模块实现某些功能的利弊,并提出在AFC系统中采用成熟模块的一些想法和建议.