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261.
The deficient performance of existing downtown transit distribution systems may significantly affect the overall performance of the urban transportation system in many metropolitan areas. This paper has two principal objectives. First, it describes an approach entitled Performance Requirements Analysis for developing a set of requirements or standards that a downtown transit system should satisfy and structuring these requirements so as to generate a small set of alternative generic systems for detailed evaluation. Second, it provides a preliminary assessment of performance requirements for distribution systems in 19 of the largest cities in the United States.  相似文献   
262.
In the last decades, due to the population increase and the relative need of new land to cultivate, expand urban centers and develop transportation networks, most of the Italian natural protected areas are subject to different typologies of human pressures that generally cause habitat fragmentation. This process represents a major concern for biodiversity conservation and a key driver of species loss.The main purpose of this paper was to investigate levels of natural habitat fragmentation due to roads and railways networks in the Italian National Parks (INPS) through the use of an Infrastructural Fragmentation Index (IFI).All the operations (geospatial analysis, image classification, and fragmentation analysis) were performed using a Geographic Information System (GIS) software for elaborating a national database. The obtained results include an IFI value for each natural territorial unit inside any INP. Moreover, in order to highlight which are the INPS characterized by higher infrastructural fragmentations, an IFI weighted mean was calculated for each INP. These results represent important indicators for the prioritization of biodiversity conservation interventions and the planning of a INPS sustainable management.  相似文献   
263.
为了弥补运输通道分析方法的缺陷,本文结合运输通道"带状分布"、"客货流密集"等特征,提出了基于OD分布的运输通道定量识别方法。首先利用图论,在OD分布图上识别出所有抽象的带状路径,并结合OD矩阵筛选出其中OD量最大的一条或多条路径,然后通过区域产业轴线、城镇轴线以及交通轴线的定性验证,确定运输通道。最后,对驻马店市运输通道进行实例分析,结果表明其精确度较高,具有科学合理的实用性。  相似文献   
264.
The flight schedule of an airline is the primary factor in finding the most effective and efficient deployment of the airline's resources. The flight schedule process aims at finding a set of routes with associated aircraft type, frequency of service and times of departures and arrivals in order to satisfy a specific objective such as profit maximization. In this paper, we develop a two‐phase heuristic model for airline frequency planning and aircraft routing for small size airlines. The first phase develops a frequency plan using an economic equilibrium model between passenger demand for flying a particular route and aircraft operating characteristics. The second phase uses a time‐of‐day model to develop an assignment algorithm for aircraft routing.  相似文献   
265.
This paper investigates the Granger-causality relationship between income and transportation of EU-15 countries using a panel data set covering the period 1970–2008. In the study, inland freight transportation per capita in ton-km (TRP), inland passenger transportation per capita in passenger-km (PAS), and road sector gasoline fuel consumption per capita in kg of oil equivalent (GAS) are used as transportation proxies and GDP per capita is used as measure of income. Our findings indicate that the dominant type of Granger-causality is bidirectional. Instances of one-way or no Granger-causality were found to correspond with countries with the lowest income per capita ranks in 1970 and/or in 2008. Although we conclude that there is an endogenous relationship between income and transportation, this is not observed until after an economy has completed its transition in terms of economic development.  相似文献   
266.
ABSTRACT

This paper describes the development of a probabilistic formulation that provides global optimum selection and allocation of a fleet of buses in a private transportation system of an organization where a third party is hired to provide transportation for its employees and their dependents. In this private transportation system, a fleet of buses is to be selected and allocated to serve employees and their independents on different prescheduled trips along different routes from the organization’s headquarters and residential compound where round-trip times of scheduled trips are subject to uncertainty due to random delays. We propose a probabilistic approach based on 0-1 integer programming for the selection and allocation to determine the optimal number and size of buses assigned to a set of prescheduled trips in a particular time interval. Examples and a case study are presented to illustrate the applicability and suitability of the proposed approach.  相似文献   
267.
文章基于交通运输类专业实践教学的现状,分析了虚拟仿真技术应用于交通运输类专业教学的必要性,并介绍了虚拟仿真技术在交通运输类专业实训教学中的应用实例,供交通运输类专业实训教学及实训室建设参考.  相似文献   
268.
李国帅 《交通标准化》2013,(23):150-152
智能交通的研究课题是如何把现代的高科技与交通联系起来.结合实际阐述了智能交通系统在城市交通管理中的作用和重要性,针对我国交通现状提出了一些建议,并对智能交通未来的发展进行了探讨.  相似文献   
269.
在我国深入实施城市公共交通优先发展战略的关键时期,提高公共交通的供给能力和服务质量,进而改善居民出行条件、缓解城市交通拥堵、降低能源消耗,是目前关注的重点与热点,本文深入分析了我国城市公共交通发展面临的问题,并提出相应的对策建议,为推进我国城市公共交通优先发展提供参考.  相似文献   
270.
阐述了射频识别(RFID)的工作原理,介绍了RFID技术的应用领域,对RFID技术在交通行业不停车收费(ETC)系统中的应用情况进行了详细论述。  相似文献   
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