从北京地铁车辆厂的发展谈国产化

回顾了北京地铁车辆厂制造地铁车辆的历史后认为：国产化工作要确认识我们的长处和短处，要扬长避短；并应做好统一车辆的技术标准，充分利用现有地铁车辆生产厂家的生产能力以及人员与技术优势，加强行业管理并促进各行业的分工合作等工作，开发出我国具有独立知识产权的产品。产品必须具有先进性。但车辆的先进性不能单纯由技术指标衡量，而应建立在安全、可靠的基础之上。     

欧洲铁路信号系统安全性标准的学习与引进

针对铁路信号控制技术的发展及系统相互承认的需求，在介绍欧盟电气委员会（CEN—ELEC）针对铁路信号安全标准的基础上，结合作者的理解，指出在引进学习欧洲标准的同时，制定具体指导方针的必要性。     

缓冲结构减缓高速铁路隧道出口微压波数值比较

研究了高速铁路隧道出口微压波产生机理, 结合一维可压缩非定常不等熵空气流动理论和无限大障板圆形活塞辐射理论, 应用数值计算方法研究了不同形状缓冲结构条件下高速铁路隧道出口附近微压波规律。通过对缓冲结构形状以及各种参数计算结果进行定性与定量对比, 发现对于截面积变化的线型、抛物线型和不连续型缓冲结构, 随着长度和端口截面积增加, 隧道出口附近微压波强度衰减较大, 其中不连续型缓冲结构综合效果最佳; 而截面积为常量, 具有开孔的缓冲结构, 虽然也可较大幅度降低隧道出口附近微压波强度, 但是需要综合比较才能选取最佳结构参数。     

Access control policies without inside queues: Their properties and public policy implications

An access control policy that eliminates all queues beyond the entry points to a network has obvious benefits, which include smooth travel and predictable travel times inside the network. Yet it has never been proven, to the best of our knowledge, whether excluding inside queues yields sub-optimal network performance or, in other words, allowing inside queues can actually further reduce the system travel cost. Moreover, it is not clear whether an optimal control policy derived from efficiency considerations can also be a fair policy to all road users. This paper provide answers to these questions in the context of a monocentric network. By analyzing the structure of the access control problem considering all feasible policies (with/without inside queues), we show that the minimal system cost realizable by access control can be obtained without directly solving a non-convex optimization program, and can indeed always be achieved by a control policy excluding all of the inside queues. These optimal policies are defined by a polyhedral set and a Finite Generation Algorithm can be applied to derive the analytical form of this set. The optimal policies are not unique in general, thus making it possible to achieve both minimal system cost and fairness simultaneously.     

Airline emission charges: Effects on airfares,service quality,and aircraft design

This paper explores the effect of airline emissions charges on airfares, airline service quality, aircraft design features, and network structure, using a detailed and realistic theoretical model of competing duopoly airlines. These impacts are derived by analyzing the effects of an increase in the effective price of fuel, which is the path by which emissions charges will alter airline choices. The results show that emission charges will raise fares, reduce flight frequency, increase load factors, and raise aircraft fuel efficiency, while having no effect on aircraft size. Given that these adjustments occur in response to the treatment of an emissions externality that is currently unaddressed, they represent efficient changes that move society closer to a social optimum.     

SDH传输系统的告警维护信号

介绍了ＳＤＨ传输系统主要告警维护信号，描述了告警维护信号的含义和故障产生原因。举例说明了ＳＤＨ传输系统因传输故障所引起的告警序列。     

计算机技术在医疗保险中的应用

介绍了本单位研究开发的医疗保险信息系统,论述了该系统的设计目标、结构、功能.该系统应用后,提高了医疗保险管理效益及决策的科学性.     

Handling Safety Simulation of Driver-Vehicle Closed-Loop System with Evolutionary Random Road Input

The response simulation is studied and the handling safety is evaluated using finer integration method for driver-vehicle closed-loop system with stationary random road input. This algorithm is not only precise, but can also shorten the evaluation period of handling safety and reduce the tremendous cost for real vehicle testing. The response simulation and the vehicle handling safety evaluation are also studied for the closed-loop system with evolutionary random road input. The study can more truly simulate vehicle handling quality for including the varying of vehicle velocity with time.     

高氧液对家兔急性脑缺血损伤的治疗作用

目的　探索高氧液对兔急性全脑缺血再灌注损伤的保护作用。方法　钳闭双侧颈总动脉并降压建立家兔全脑缺血模型,18只模型随机分3组:对照组(CG) 用平衡盐液再灌注,治疗组(TG) 用高氧液再灌注,均 20 mL/kg静注;预处理组(PG)实验前3 d,高氧液 20 mL/kg静注,每天 1 次。每组在缺血前、缺血 20 min和再灌注 45 min各抽取颈内动脉血测定动脉氧分压(PaO2)和丙二醛(MDA)含量。72 h后处死动物,行海马 CA1 区组织病理学观察。结果　再灌注后TG组和PG组MDA含量与海马神经元坏死数量明显低于CG组,PaO2明显高于CG组。结论　高氧液对急性脑缺血有一定保护作用。     

Punching Shear Behavior of RC Slab-Column Connections with Nonrectangular Columns

This paper present an experimental study on the RC slab-colunm connections with nonrectangular colunms, namely cross-shaped column, T-shaped column and L-shaped column. The punching shear deformation and strength characteristics of slab-column connections with nonrectangular columns under punching shear load are investigated. Nine specimens with the three kinds of nonrectangular columns and two reference specimens with square columns are tested. The tested ultimate loads, deformations, and failur emodes of specimens are presented and discussed. Test results reveal that the punching shear strength and ductility of the connections with nonrectangular columns are higher than those of the corresponding connections with square columns, and also prove that the application of nonrectangular columns to flat-plate structure was feasible. Based on the test results, one method of calculating punching shear strength of connections with nonrectangular columns is proposed, which conforms with the current design practice of China. The test results on the punching shear strength are compared with the predictions of the formulas proposed by codes of several different countrie; and the predictions given by ACI code and China code are found to be conservative as the reinforcement ratio is increased.