长春轻轨3号线东延线过渡段信号改造方案分析

轨道交通延伸线工程的接合处车站改造方案是影响整个工程实施的关键因素。针对长春轻轨3号线东延线过渡段2个车站信号系统的改造,详细探讨和分析信号设备变动和施工量,提出整体改造可行性方案,从工程实施难度和风险、节省投资等多个角度进行了比选。     

Coastal erosion and sea level rise: Implications for ocean beach and San Francisco's westside transport project

Abstract

One of the consequences of sea level rise resulting from the greenhouse effect is increased coastal erosion. This article discusses a model of erosion that can be used to estimate the response of beaches to sea level rise. The model is applied to Ocean Beach, California, with particular attention to the consequences of accelerated erosion for the San Francisco Westside Sewer Transport. Results obtained show that erosion produced by accelerated sea level rise could cause substantial damage to the structure. Large expenditures on beach nourishment will be required to protect the transport and the recreational value of the beach.     

再生混凝土骨料沥青混合料级配设计新方法探讨

为了解决再生混凝土骨料应用于沥青混凝土级配设计时出现的新情况、新问题,应用拉格朗日乘数法和Excel规划求解建立了适于再生混凝土骨料沥青混合料级配设计的精确计算模型及应用程序。结果表明拉格朗日乘数法是解决问题的理论基础,也是建模的核心,而Excel规划求解是对前者的改进和延伸,从而从理论与实践两方面有效地解决了该问题,并使之在工程的质量控制方面得到推广。     

铁路行包装运方案计算机辅助编制系统的研究

基于全路客车行李车开行方案,综合分析行包作业的约束条件和关联因素,按照优先直达、合理中转及合理运输路径距离等原则,采用“穷举计算,逐一筛选,分类排序”的算法,提出全路行包办理站之间站到站的行包装运方案模型.基于本文提出的模型和算法,设计开发了铁路行包装运方案的计算机辅助编制系统,分为上游站运能运量预报子系统和车站辅助装车计划子系统,该系统有利于提高铁路行包运输装车计划编制和中转计划编制的工作效率.     

高职订单式人才培养的探索

订单式人才培养为我院的教学改革带来很好的效果,也遇到校企合作人才培养目标的差异、实践教学难度大、师资培训成本较高、学生就业面窄等问题,我们通过多年的实践探索,提出了相关的对策。     

计算机网络技术在财务系统中的应用

网络会计是信息技术的发展而使财务会计系统变革的产物.介绍了网络会计的特点,网络会计的内容及处理程序以及网络会计所面对的问题和对策.     

面向对象的桥梁CAD建模分析

在桥梁设计过程中,将大量复杂而繁琐的设计计算、图表查询等任务交给计算机去完成,是桥梁CAD系统要完成的主要工作之一。过去,这种CAD系统的开发均采用面向过程的建模方法,用这种方法所得到的程序提供的一个面向工程的桥梁设计计算程序,不仅可读性差,更致命的是条件稍做更改,程序便要做相当大的变动,且可扩充性及可维护性差。将20世纪90年代的设计方法——面向对象技术应用于这类系统之上,是桥梁CAD系统今后发展的方向之一。适应这一发展要求,进行桥梁CAD系统面向对象的建模方法研究具有重要的意义。     

Price effects of airlines frequent flyer programs: The case of the dominant firm in Chile

Frequent flyer programs create a switching cost for the consumer and allow firms to obtain rents, for example, by exploiting the principal agent problem existing between the employee who travel and purchases the ticket and the employer paying for that ticket. In Chile LAN is the dominant airline in domestic markets and the only one that has a frequent flyer program (FFP); it faces some competition from two small carriers. Using a unique dataset for Chile, collected by ourselves from airlines websites in 2011 and 2012, we estimate the impact of the dominant airline FFP. For this purpose, we compare for each route the fares between airlines and between weekday trips (that accumulate full miles and are mainly for business purposes) and weekend trips (that accumulate less than full miles and are mainly for leisure purposes). The results show that the differential premium LAN is able to charge for weekday trips due to the FFP is around 35%. Three particularities of the Chilean market help the econometric identification: there is only one hub for all airlines (the capital city of Santiago), there is no business class in domestic flights, and none of the airlines is a low-cost carrier.     

The influence of employer ridesharing programs on employee mode choice

Employer ridesharing programs and employee mode choice were analyzed using Southern California data. Problems in estimating the costs and benefits of employer ridesharing programs were identified. Surveyed firms used a wide variety of information to estimate employee mode split internally. Virtually all surveyed firms offered free or subsidized parking to some or all of their employees. Few responding firms estimated the cost of providing employee parking accurately, if at all. Despite these significant data limitations, factors influencing firm choice of employer ridesharing program components were identified. The influence of employer ridesharing programs on employee mode choice was modeled using weighted least squares logit regression analysis. Firm size was foung to be the single most important variable identified in the analysis. Larger firms were more likely to offer ridesharing incentives to their empolyees, and to report direct employer benefits from ridesharing. Alternative work hours hindered the formation of ridesharing arrangements in some cases. Relatively few firms promoted ridesharing on a purely voluntary basis. A private market for employer ridesharing services was found to exist, however. Personalized matching assistance may be a critical factor in developing more effective employer ridesharing programs. Parking pricing and supply control measures probably would have a larger impact on employee mode split overall. Parking management faces severe obstacles in implementation, some of which might be overcome through the more extensive provision of ridesharing services, such as personalized matching assistance. to employees at specific employment sites by their employers.     

线路纵断面设计中碎小坡段的编程处理

碎小坡段是铁路线路纵断面设计中常见的问题,实践证明,将纵断面中的碎小坡段与其相邻坡段进行合理调整,可以消除线路纵断面设计中出现的一部分碎小坡段,但需要很多次的试验。为了高效消除纵断面设计过程中出现的碎小坡段,本文应用计算机编程技术,建立FORTRAN语言程序,通过不同的算法,合理地计算调整坡度和坡段长度,得出解决碎小坡段的备选方案。