关于优化西张支线行车组织办法的调查和思考

为了提高站段自主管理能力、充分发挥“大站带小站”的优势,实现生产力布局调整提高运输效益的目的,根据生产力布局调整后出现的新情况、路局调研课题要求和车站提高运输组织的需要,结合西张支线的现状、特点,现对西张支线行车组织办法做如下调查和思考。     

新形势下如何适应铁路建设项目的投资包干

针对铁路建设项目投资包干的新形势,笔者从6个方面总结和论述了建设项目投资包干的做法.     

通用微机在工业控制中的抗干扰技术

作者讨论了通用微机面临工业控制现场抗干扰能力差的问题,提出一适合中小企业的工控系统方案,实现后在现场得到了广泛应用。文中较详细地阐述了该系统所采取的抗干扰措施。     

SS4型电力机车传动控制系统的仿真研究

以ＳＳ４型电力机车传动控制系统为研究对象，用ＳＩＭＵＬＩＮＫ软件建立仿真模型，通过构造系统仿真模块和工具模块，既仿真了双闭环自动控制系统在机车恒流启动过程中相关量的变化情况，又实现了系统的功率因数分析和谐波分析。     

Confidence bounds on structural reliability estimations for offshore platforms

Second-order estimates to measure platform reliability are generated and used to provide an additional space to select safety margins appropriate to the owner's perception or for risk-averse managers. The aleatory and epistemic uncertainties in the parameters of an offshore platform are explicitly considered in the reliability analysis and the platform structural reliability becomes a random variable, assessing then the beneficial effects of a reduction on these uncertainties. One of these benefits is for risk-aversive managers who often demand additional room to make conservative decisions regarding reliability estimations. Proposed here is a procedure to generate the frequency diagram of platform reliability with the use of confidence bounds to support reliability and cost decisions based on percentiles instead of mean values. The concepts are illustrated through a typical offshore platform in Mexico. The frequency diagram of the platform reliability index is built for several alternative designs and three levels of epistemic uncertainty. The results may be applied for decision making on new designs and also on the assessment and optimal inspection, retrofit, and decommissioning of existing platforms.     

货车脱轨自动制动阀可靠性的探讨及建议

根据脱轨制动阀的作用原理，结合生产中遇到的情况，探讨影响运用可靠性方面的问题，并提出一些建议。     

Using system dynamics in maritime economics: an endogenous decision model for shipowners in the dry bulk sector

In this paper, we consider the benefits of applying system dynamics in maritime economics. We build an endogenous shipowners' model for the dry bulk sector, incorporating both the decision process of individual shipowners and traditional shipping market conditions. The aim is to arrive at a simulation tool that can be used for a variety of applications, both for teaching/learning and for research purposes. Within the endogenous shipping model, we can distinguish between the strategic and the tactical choices shipowners face. As an application, we focus explicitly on a strategic decision-making process that is relevant to any shipowner, i.e. the sale of a vessel. System dynamics seems to be a tool well-suited for the detailed modelling of strategic and operational behaviour in the maritime business.     

72.5 kV GIS系统在松花江大顶子山航电枢纽工程水电站的应用

着重介绍全封闭组合电器的特点、安装方法和安装过程中应注意的事项,增加对全封闭组合电器的掌握,有利于设备更加安全稳定运行。     

The Added Value of Accounting For Users’ Flexibility and Information on the Potential of a Station-Based One-Way Car-Sharing System: An Application in Lisbon,Portugal

Car-sharing systems are an alternative to private transportation whereby a person may use an automobile without having to own the vehicle. The classical systems in Europe are organized in stations scattered around the city where a person may pick up a vehicle and afterward return it to the same station (round trip). Allowing a person to drop off the vehicle at any station, called one-way system, poses a significant logistics problem because it creates a significant stock imbalance at the stations, which means that there will be times when users will not have a vehicle available for their trip. Previous mathematical programming formulations have tried to overcome this limitation by optimizing trip selection and station location in a city in order to capture the best trips for balancing the system. But there was one main limitation: The users were assumed to be inflexible with respect to their choice of a station, and held to use only the one closest to their origin and destination. If the user is willing to use the second or even the third closest station the user could benefit from using real-time information on vehicle stocks at each station and be able to select the one with available capacity. In this article we extend a previous model for trip selection and station location that takes that aspect into account by considering more vehicle pick-up and drop-off station options and then apply it to a trip origin–destination matrix from the Lisbon region in Portugal. Through the extended formulation we were able to conclude that user flexibility allied with having information on vehicle stocks increases the profit of the company, as people will go directly to a station with a vehicle available, thus making the use of the fleet more efficient. Observing the size of the stations resulting from the model, we also concluded that the effect of information is enhanced by large car-sharing systems consisting of many small stations.     

Causality between performance and traffic: an investigation with Indian ports

This paper attempts to find out the causal relationship between port performance and port traffic by using Indian data. The use of cointegration analysis has come out with the result that performance precedes traffic in most of the ports of India. Hence, government policy towards performance augmenting facilities should be given priority so that higher efficiency induces higher traffic