CRTS Ⅲ 型无砟轨道基础结构冲击试验与数值分析

利用CRTS Ⅲ 型板式无砟轨道−路基系统实尺模型开展落轴冲击试验,同时运用Ansys/LS-Dyna软件进行轨道−路基落轴冲击动力有限元模拟分析,在试验结果和数值结果对比验证的基础上,系统研究落轴荷载作用下轨道和路基结构动应力分布规律,比较落轴高度和加载位置对动应力分布的影响。研究结果表明：试验结果和数值结果具有较好的一致性,两者可以相互验证,互为补充。轨道结构各层动应力均在钢轨正下方达到最大值,动应力幅值沿线路横向分布总体上呈驼峰形分布;沿线路纵向大致呈正态分布,自密实层应力幅值在板端附近有明显地回弹。路基动应力幅值底座板宽度范围内,沿横向分布比较均匀,在底座板宽度范围外快速衰减;沿线路纵向大体上呈正态分布;路基动应力幅值沿深度的衰减速度随着深度的增加而减小,在基床内衰减较快,基本呈线性或者分段线性衰减,在路基本体内衰减非常缓慢。轨道和路基动应力幅值总体上随落轴高度增加而线性增加,但沿线路纵横向分布规律不变。相对于板中加载,板端加载时轨道和路基各层面动应力幅值均有所增大,越靠近加载点增幅越明显,但是2种加载条件下轨道和路基结构应力幅值分布规律基本一致。     

有轨电车售检票方案综合分析

研究有轨电车的封闭式、开放式、混合式售检票方案,并进行方案比选,建议有轨电车工程初期采用开放式售检票方案,近远期采用封闭式售检票方案。     

Operational performance evaluation of major container ports in the Asia-Pacific region

If international container ports are to gain a proper appreciation of their various advantages, disadvantages and potential opportunities in a globally competitive environment, it is essential that they conduct effective evaluation of their operational performance. The present study applies five models of data envelopment analysis (DEA) to acquire a variety of complementary information about the operational efficiency of major container ports in the Asia-Pacific region and to identify trends in port efficiency. The study first establishes the causes of inefficiency on the basis of efficiency value analysis. Slack variable analysis is then used to identify potential areas of improvement for inefficient ports. This is followed by the utilization of return to scale analysis to assess whether each port is in a state of increasing, decreasing, or constant return to scale. Finally, a sensitivity analysis is conducted to identify which input or output variables have larger weights in terms of efficiency. The results provide valuable information for port managements in their attempts to establish competitive strategies for the future and to improve their resource utilization for ongoing improvements in operational efficiency.     

我国道路交通事故改善措施探讨

通过将国内变通安全的现状与西方发达国家进行比较．分析出我国变通事故独有的特点。阐述了目前我国变通事故多．死亡率高的主要原因。借鉴发达国家的成功经验。有针对性地给出了减少变通事故的可行而有效的措施。     

机冷车制冷压缩机性能的测试方法

机冷车作为铁路冷藏运输工具,主要用于易腐货物的运输服务.由于货物装载方法不当及大量的水果、蔬菜不经预冷处理,特别在夏季,货物装入机冷车后,制冷机组通常得连续运转48小时以上,才能将货温降到规定的承运温度.在上述情况下,一旦压缩机发生故障,将严重危及承运货物的质量,极易造成货损.本文就如何检测压缩机、确保压缩机良好的方法,进行分析如下:……     

油田流动污水介质中溶解氧对A3钢腐蚀行为的影响

通过腐蚀管流动态模拟装置,模拟现场工艺条件,研究了暴氧和除氧条件下,油田流动污水介质中A3钢的腐蚀行为。用失重法和交流阻抗、极化曲线方法,揭示了A3钢在油田污水介质中腐蚀的电化学规律。结果表明:A3钢在油田污水介质中的腐蚀受阴极氧的去极化控制,流动过程和溶解氧共同作用,极大地加速了油田污水介质对A3钢的腐蚀性。     

Selection of techniques for reducing shipping NOx and SOx emissions

This paper develops a subjective generic methodology for providing ship owners with a transparent evaluation tool for selecting their preferred NOx and SOx control techniques. We quantitatively analyse the merits of the control methods available in marine air pollution control practice using data collected from shipping companies, shipyards and maritime academies. We also prioritize the applicable control techniques with respect to operational shipping environments.     

内燃机车检修规章的网络化管理

济南西机务段配属内燃机车175台，主要担当京沪线间丰台至济南西、济南西至徐州间的货物列车牵引任务；同时承担本段ND5型内燃机车简易大修、中修、定修和DF8B型、DF7型内燃机车的小辅修工作。机车检修工作直接涉及到检修、检测、设备、运用车间，电机大修厂、技术科、验收室、材料科、职教科、企管办等多个部门的140多个岗位，有1200余名职工参与，使用各级规章500多个。     

来曲唑与克罗米酚在诱导多囊卵巢综合征患者排卵中的作用

目的探讨来曲唑(LE)与克罗米酚(CC)在诱导多囊卵巢综合征(PCOS)患者排卵中的作用。方法选择在我院就诊的PCOS排卵障碍患者46例(58个周期),随机分为LE组和CC组,分别用LE、CC进行促排卵治疗,比较两组发育及成熟卵泡数、排卵数、平均卵泡直径、子宫内膜厚度及形态、排卵率、黄体化卵泡未破裂(LUF)的发生率及妊娠率。结果CC组发育和成熟卵泡数、注射绒毛膜促性腺激素(hCG)日及排卵后1周血清雌二醇浓度、LUF发生率较LE组显著升高(P<0.05),而注射hCG日子宫内膜厚度、子宫内膜三线征阳性率(A型%)显著低于LE组(P<0.05);两组血清孕酮浓度、排卵率及妊娠率无显著性差异。结论LE适合PCOS患者的诱导排卵治疗,有望作为PCOS患者的一线促排卵药物。     

Reliability Analysis of Systems with Common Cause Failure Based on Stress-Strength Interference Model

Many mechanical systems have the characteristics of multiple failure modes and complex failure mechanisms. On the basis of stress-strength interference (SSI) model, this paper takes the mechanical system with common cause failure (CCF) as the research object. The relationship between the stress distribution and the strength distribution is studied, and the failures of components are independent of each other under the deterministic stress. Then, the concept of conditional reliability is introduced to build the system reliability models under the action of one-stress and multi-stress for both series and parallel systems. Finally, the corresponding properties of the proposed methods are discussed to show their advantages.