企业内部成本核算中的单价变更简易计算法

针对建筑企业内部成本核算与业主对计量的不同要求，以土石方工程为例，提出企业内部在合同实施过程中，应实事求是地进行分项工程单价调整，并给出简易计算公式。     

铁路工程T梁不同运架方式施工工艺及造价分析

目前,铁路建设的T型梁运输架设,一般采用“边铺边架”的施工组织方案,该方案存在架梁方向单一、工作面少的缺点。为了弥补这种单一运架方式的不足,达到增加工作面,赶工期的目的,出现了汽车吊架梁、公铁两用架桥机架梁方式。此文通过调研,阐述这2种运架梁方式的施工工序及工艺,并针对现行铁路工程定额体系中的缺项部分进行分析与补充,希望能为今后的类似工程设计施工起到借鉴作用。     

对公路工程项目施工成本控制的探讨

对公路施工项目施工成本的构成、项目核算办公室成立及功能进行阐述，采用统计、核算、监督、控制的手段对施工项目成本进行控制，及时反馈有关费用并进行分析整理。做到堵漏、增效。     

加速发展我国高性能船舶和水上高速客运

为开发海洋经济，发展海上运输，加快海军现代化建设步伐，必须加速发展高性能船舶和水下高速客运。为此，本文提出了有关决策层参考的几点政策性建议。     

轿车保险杠的设计

轿车保险杠是轿车整体造型的重要组成部分,与周边零件的搭接关系十分密切,保险杠在造型和结构设计阶段要充分考虑制造可行性以及工艺实现的难易程度。文章介绍了几款车型的造型面和结构处理方式,以及一套模具满足不同配置要求的结构设计,表明了保险杠的造型和结构设计对整车优化工艺和降低成本的重要性,指出美观而合理的造型,能为制造和运输等工序提供良好基础,使成品率和稳定性得到提高。     

Engaging disadvantaged populations in transport studies: Linking modal use and perceptions of safety to activity patterns

Accessibility measures are important tools in planning. However, if the data are not available to adequately capture the mobility and accessibility challenges of disadvantaged populations, than the results of the model provide little to no direction for policy makers. This paper explores data collection techniques that have the potential to address the “why” underlining the activity behavior, especially linking personal safety perceptions to activities. The first study comes from a series of focus groups with low-income women in Quebec City, Canada. Self-mapping of individual spaces creates a framework to address spatial and temporal challenges that negatively impact transit dependent populations. The second study focuses on the activity patterns of low-income immigrant youth in Providence, RI. A technique is presented to elicit formatted responses concerning perceptions of personal safety. With the help of GIS, this technique has the potential to link together activities and perceptions of safety for activity modeling.     

Cost scaling based successive approximation algorithm for the traffic assignment problem

This paper presents a cost scaling based successive approximation algorithm, called ε-BA (ε-optimal bush algorithm), to solve the user equilibrium traffic assignment problem by successively refining ε-optimal flows. As ε reduces to zero, the user equilibrium solution is reached. The proposed method is a variant of bush-based algorithms, and also a variant of the min-mean cycle algorithm to solve the min-cost flow by successive approximation. In ε-BA, the restricted master problem, implying traffic equilibration restricted on a bush, is solved to ε-optimality by cost scaling before bush reconstruction. We show that ε-BA can reduce the number of flow operations substantially in contrast to Dial’s Algorithm B, as the former operates flows on a set of deliberately selected cycles whose mean values are sufficiently small. Further, the bushes can be constructed effectively even if the restricted master problem is not solved to a high level of convergence, by leveraging the ε-optimality condition. As a result, the algorithm can solve a highly precise solution with faster convergence on large-scale networks compared to our implementation of Dial’s Algorithm B.     

Sociological perspectives on travel and mobilities: A review

There is increasing interest in understanding and achieving changes in travel behaviour, but a focus on individual behaviour change may overlook the potential for achieving change via transformation at the levels of institutions, cultures and societies – the domains of sociological inquiry. In this paper, we review sociological contributions to the literature on travel and ‘mobilities’. We summarise four key themes which supplement or contradict arguments made in mainstream transport debates on behaviour change. The first involves focusing on travel ‘practices’ as social entities with dynamics of their own, rather than on individual behaviours. The second relates to the changing natures of societies, and the implications for travel. The third explores and interprets the issue of car dependence in ways which highlight the ethical, experiential and emotional dimensions associated with car use, its symbolic role in societies increasingly concerned with consumption, and its differing roles within different cultures. Finally, the ‘new mobilities paradigm’ highlights issues such as the increasing links between travel and new technologies, and the primacy of social networks in influencing travel decisions. These themes emphasise the importance of understanding the broader contexts in which travel choices are made. In particular, the implication is that the creation of more sustainable travel patterns will require changes at a range of social levels, not simply in individual behaviours, and that changes to transport will inevitably be linked with, and influenced by, broader changes in the values and practices developed by societies as a whole.     

Sub‐optimal decision‐making and the transportation problem

A modification to the transportation problem is outlined that aims to improve the quality of predictions of trip matrices, and at the same time, allow some behavioural and economic insights. A framework is suggested within which this modification may be made and a suitable statistic and iterative process are described. A simple example demonstrates the validity of the modification and suggests some areas of difficulty with the approach.