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通过对原可行性研究报告中的锅炉房用煤采用筒仓群贮存方案的了解、分析、比较后,提出了采用矩形库贮存煤的优化方案设计的成果。 相似文献
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从物流及第三方物流的概念着手,主要分析了物流与铁路运输的本质区别,并就铁路运输开展第三方物流优势及存在问题进行了详细分析,重点论述了铁路运输业开展第三方物流的可行性及有关对策。 相似文献
4.
油气长输管道在运行过程中易受到自然和人为因素的破坏,例如:洪水冲刷、防腐层老化、阴极保护失效、管道占压、不法分子打孔盗油(气)引起管体缺陷等,因此,管道抢修是管道运行管理工作中的重要组成部分。为了延长管道的使用寿命,避免停输抢修给企业造成不必要的经济损失,对不停输抢修技术在长输管道中的应用进行了研究,有效地降低了管道经营成本,对企业进行油气管道运行管理具有一定的借鉴指导意义。 相似文献
5.
Park-and-ride services are an important component of many public transportation systems in the United States. Locating park-and-ride facilities is an essential step when planning for these services. In this research we focus on three major siting/modeling concerns that need to be addressed when siting park-and-ride facilities: covering as much potential demand as possible, locating park-and-ride facilities as close as possible to major roadways, and siting such facilities in the context of an existing system. Unfortunately, existing models do not enable each of these concerns to be simultaneously addressed. This paper presents a multi-objective spatial optimization model for integrating these considerations. This model is applied for siting park-and-ride facilities in Columbus, Ohio. Application results show the usefulness of the developed model in supporting transit planning in an urban region. 相似文献
6.
Efrat Blumenfeld-Lieberthal 《Networks and Spatial Economics》2009,9(3):427-458
This paper presents an analysis of the topology of transportation networks within different systems of cities. Urban entities
and their components are complex systems by their nature; there is no central force that affects their spatial structure.
Thus, we study transportation networks within different countries as complex networks. Based on the above, we consider cities
as nodes, while direct air and railways routes represent the links. We present characteristics of these networks including
their degree and clustering coefficient. Transportation networks can be used as an indicator of economic activity between
cities. Cities with strong economic relationship are characterized by high volume of connectivity. Our findings suggest that
the topology of the analyzed transportation networks can be used to classify the countries they belong to based on their economic
development.
相似文献
Efrat Blumenfeld-LieberthalEmail: |
7.
The US workforce is aging. At the same time, there are a record number of open positions in the transportation sector, which has traditionally been a well-paying, but stressful and schedule-dependent, occupation. Due to increasing longevity, need, and ability to work, a possible solution to the transportation workforce shortfall may lie within the retention and recruitment of older workers. This paper uses a socio-technical framework to examine the pertinent, though scant, literature and data related to older workforce demographics and operational needs, the regulatory environment, requisite knowledge, skills and abilities, and application of support technology and training. Although there is evidence of age-related changes in physiology and cognition, the current science remains unable to resolve how an older workforce may most appropriately be applied to transportation to maximize system safety and minimize negative impact to worker well-being. 相似文献
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车辆定位与导航系统是智能交通系统中当前需求较为迫切、应用比较广泛的一个重要的应用系统,是国际上公认的解决城市交通问题的有效途径之一。本文通过分析给出了智能车辆定位与导航系统的组成,并详细分析了核心技术。最后,给出了系统的硬件平台。 相似文献
10.
In the literature on transit planning, network timetabling and vehicle scheduling are usually treated as separate problems. In this paper, we focus on combining important features of these two steps and propose a simultaneous solution approach to redefine timetables with the objective of bringing improvements to both quality of service and vehicle costs incurred. This includes the objectives of quantity and quality of the transfers proposed, evenness of the line headways, fleet size and length of the deadheads. The model proposed for this simultaneous approach is adapted to the problem faced by regulating authorities, encouraging intermodality and taking into account a variety of practical features. We introduce an optimization procedure based on Iterated Local Search and present computational experiments carried out on data from a large existing transit network, showing substantial improvements in both quality of service and level of resources compared to the current practice. 相似文献