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101.
The purpose of an economic appraisal of a transportation project is to help select an efficient transportation investment plan. Here, efficiency means achieving the best transportation service from a given investment and the generation of net benefits at least as great as the costs of the investment. In this article, three future transportation investment alternatives in the USA are compared using the benefit-cost ratio method to illustrate the economic desirability of the AVCS Maglev alternative – an advanced vehicle control system based on magnetic levitation and propulsion. For the completeness of the economic appraisal and the provision of a guide to performing non-user benefit analysis for this promising ITS technology, the socioeconomic effects of implementing AVCS Maglev in the USA are evaluated based on the US National Development Model (NDM).  相似文献   
102.
This article introduces a theme issue of the Coastal Management Journal comprising a set of articles on the potential economic benefits from new investments in coastal ocean observing systems. We describe a methodology to estimate these benefits, and apply this methodology to generate preliminary estimates of such benefits. The approach focuses on coastal ocean observing information within ten geographic regions encompassing all coastal waters of the United States, and within a wide range of industrial and recreational activities including recreational fishing and boating, beach recreation, maritime transportation, search and rescue operations, spill response, marine hazards prediction, offshore energy, power generation, and commercial fishing. Our findings suggest that annual benefits to users are likely to run in the multiple $100s of millions of dollars. The project results should be considered first-order estimates that are subject to considerable refinement as the parameters of regional observing systems are better defined, and as our understanding of user sectors improves.  相似文献   
103.
This paper reports the impacts of economic analysis results on sea-level rise adaptation decision making with different economic analysis methods. The methodology was applied to Hillsborough County, Florida. A general conclusion is that partial shoreline protection should be implemented to reduce the potential impacts of sea-level rise on important land use, then transportation infrastructure is preferred to be protected or accommodated, and finally managed relocation should be adopted. More specifically, the results show that the best adaptation strategy is shoreline protection plus transportation infrastructure accommodation; the length of shoreline protection plays an important role in the economic analysis results, and shoreline protection and accommodation adaptation strategies for all areas are not recommended because of either high costs or low benefits; the value of travel time saving and spatial autocorrelation play important roles in the economic analysis results of accommodation strategy, which highlights the importance of including indirect economic factors and spatial autocorrelation impacts when making sea-level rise adaptation decisions.  相似文献   
104.
The growth of whale-watching internationally has been spectacular. It now occurs in almost 100 countries and is estimated to be worth in excess of U.S.$1 billion each year in revenue. Thus, whales have become valuable as a resource for tourism. The Vava'u island group in the northern part of the Kingdom of Tonga in the South Pacific is an area with a growing reputation as a whale-watching destination. However, the industry is relatively new there and the impacts of whale-based tourism in these islands is, as yet, unknown. In addition, there has been a recent consideration of a return to hunting whales in Tonga. As a result, concerns regarding the value of these animals for tourism and the potential impact of a return to hunting have arisen. Consequently, a study was designed to provide a preliminary assessment of the economic impacts of these animals for the island community. This study estimates that humpback whales may be worth in excess of U.S.$700,000 annually as a tourism attraction and that there is significant potential for future growth. Furthermore, the study shows that current visitors are opposed to any resumption of whaling practices in the islands and that such a move would likely displace large numbers of tourists from Tonga. Thus, it is concluded that a resumption of whaling in Tonga would likely have a significant opportunity cost in terms of lost tourism revenues.  相似文献   
105.
文章从营运车辆"零公里"团购加油可行性分析出发,从政策上、技术上等几个方面对在货运站场实行营运货车"零公里"团购加油的可行性进行了充分的阐述和分析,提出了营运货车"零公里"团购加油站点的最小经济规模确定方法和对应的货运站场规模的确定方法,为实施营运货车"零公里"团购加油模式奠定了理论及实践基础。  相似文献   
106.
Abstract

Near future travel-time information is one of the most critical factors that travellers consider before making trip decisions. In efforts to provide more reliable future travel-time estimations, transportation engineers have examined various techniques developed in the last three decades. However, there have not been sufficiently systematic and through reviews so far. In order to effectively support various transportation strategies and applications including Intelligent Transportation Systems (ITS), it is necessary to apply appropriate forecasting methods for matching circumstances in a timely manner. This paper conducts a comprehensive review study focusing on literatures, including modern techniques proposed recently, related to travel time and traffic condition predictions that are based on ‘data-driven' approaches. Based on the underlying mechanisms and theoretical principles, different approaches are categorized as parametric (linear regression and time series) and non-parametric approaches (artificial intelligence and pattern searching). Then, the approaches are analysed for their strengths, potential weaknesses, and performances from five main perspectives that are prediction range, accuracy, efficiency, applicability, and robustness.  相似文献   
107.
This paper describes the development of approaches to analysing the links between investment in transit and economic development. It indicates the need to bring together disparate approaches from urban economics and transportation economics to get a full understanding and uses recent results on agglomeration economies to present a more rigorous model of the wider economic benefits of transit investment. Although the evidence increasingly points towards identifiable benefits over and above those captured in conventional transport cost-benefit analysis, the chapter counsels against the assumption of simple rules.  相似文献   
108.
京津冀地区城际快速铁路网形成要素分析   总被引:3,自引:0,他引:3  
研究目的:在京津冀地区城际快速铁路网规划的基础上,结合城际铁路的客流特点及功能定位分析,着重分析论述这一区域形成规划的城际快速铁路网的主要要素。 研究方法:结合城际铁路客流特征及功能定位分析,通过对该区域社会经济、城市群及交通经济带这三方面要素现状存在的主要问题及未来发展趋势分析论述,确定支撑区域城际铁路网的主要要素。 研究结果:京津冀地区社会经济、城市群及交通经济带形成与发展方面具有得天独厚的区位优势和资源优势,这三个要素的形成与发展必将带来区域内各城市问商务、旅游、探亲等人员出行次数的增加,从而形成强大的区域内城市之间旅客交流,支撑规划的该区域城际快速铁路网。 研究结论:社会经济、城市群及交通经济带形成与发展是支撑该区域城际快速铁路网形成的主要要素。  相似文献   
109.
介绍柏家沟中桥原状及有关情况,分析病害缘由,提出改造方案,通过经济比较,确定加宽改造,改善了车辆荷载的通行能力.  相似文献   
110.
介绍了企业标准化的概念和重要意义,以及目前企业标准化工作存在的问题,并提出了发挥企业标准化积极作用的建议和措施。  相似文献   
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