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81.
基于土地开发收益的轨道交通间接利益还原模式研究 总被引：1，自引：0，他引：1
分析了目前我国城市轨道交通的投资和运营资本的来源和现状,结合廊道效应阐述了轨道交通对沿线区域土地不动产带来的利益及利益分配的不合理性。按照轨道交通对城市的功能作用,可分为引领城市的合理发展而建设的轨道交通和解决城市交通拥挤问题而建设的轨道交通两种情况,并分别讨论了间接利益的还原方式和指出要保证间接利益还原的合理性。 相似文献
82.
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
83.
AbstractNear 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
84.
AbstractThe expanding older population is increasingly diverse with regard to, for example, age, income, location, and health. Within transport research, this diversity has recently been addressed in studies that segment the older population into homogeneous groups based on combinations of various demographic, health-related, or transport-related factors. This paper reviews these studies and compares the segments of older people that different studies have identified. First, as a result of a systematic comparison, we identified four generic segments: (1) an active car-oriented segment; (2) a car-dependent segment, restricted in mobility; (3) a mobile multi-modal segment; (4) and a segment depending on public transport and other services. Second, we examined the single factors used in the reviewed segmentation studies, with focus on whether there is evidence in the literature for the factors’ effect on older people's travel behaviour. Based on this, we proposed a theoretical model on how the different determinants work together to form the four mobility patterns related to the identified segments. Finally, based on current trends and expectations, we assessed which segments are likely to increase or decrease in future generations of older people and what should be done to support the multi-optional and independent mobility of older people. 相似文献
85.
高聚物注浆维修高速公路病害技术是公路养护维修技术领域的新成果,体现了非开挖、精细化的理念,具有施工快捷、根治病害等优点,与传统维修方式相比,体现了显著的经济效益和社会效益。以安新高速公路示范工程为例,从直接效益和间接效益两方面对高聚物注浆技术和常规开挖换填两种方案进行了分析评价,结果表明高聚物技术具有明显的经济效益,可节省费用10552．73万元,效益提高56．56％。 相似文献
86.
The lack of a proper integration of strategic Air Traffic Management decision support tools with tactical Air Traffic Control interventions usually generates a negative impact on the Reference Business Trajectory adherence, and in consequence affects the potential of the Trajectory-Based Operations framework. In this paper, a new mechanism relaying on Reference Business Trajectories as a source of data to reduce the amount of Air Traffic Controller interventions at the tactical level while preserving Air Traffic Flow Management planned operations is presented. Artificial Intelligence can enable Constraint Programming as it is a powerful paradigm for solving complex, combinatorial search problems. The proposed methodology takes advantage of Constraint Programming and fosters adherence of Airspace User’s trajectory preferences by identifying tight interdependencies between trajectories and introducing a new mechanism to improve the aircraft separation at concurrence events considering time uncertainty. The underlying philosophy is to capitalize present degrees of freedom between layered Air Traffic Management planning tools, when sequencing departures at the airports by considering the benefits of small time stamp changes in the assigned Calculated Take-Off Time departures and to enhance Trajectory-Based Operations concepts. 相似文献
87.
Forest operations use fossil fuels, which should be considered when environmental impact in the wood procurement is of concern. Road freight transportation is the most common operation in timber transportation, and thus is an important source of greenhouse gas emissions. This study assesses the impact of the new larger and heavier vehicles (LHV) on environmental emissions using the synchronized calculation method. The maximum (theoretical) and operational effects of 76 t LHV with calculations made for three weight limits (60, 64 and 68 t) are compared in Finland. Based on Enterprise Resource Planning (ERP) data, environmental energy efficiency (measured in relation to the trip) increased 9.2%. The reduction in fuel consumption was 12.5%, though this is likely to under-estimate the long-term effects that will be achieved when forest operations are fully adjusted to the maximum weight limit. A comparison with the European countries and a preliminary sensitivity analysis of the system demonstrate that the technological development to improve the transporting efficiency is essential for realizing 76 t LHV utilization in Finland. 相似文献
88.
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
89.
电动汽车换电站同时作为储能电站,既可实现经济获利,又兼顾电网支撑,但目前缺乏这种储换一体站的容量配置研究. 为此,本文首先分析储换一体站工作模式及电价时段,构建一体站的运行模型;然后,基于用户出行模拟,建立电动汽车换电需求预测模型;接着,建立考虑全寿命周期收益和电网支撑能力的储换一体站容量双层规划模型,外层规划以全寿命周期总收益为目标,实现储换一体站的容量规划,内层规划以对电网支撑能力为目标,实现电池组充放电行为优化,内层获得最优充放电功率并返回外层,实现储换一体站容量最优配置;最后,在 IEEE33 节点系统上验证规划模型的有效性,为储换一体站建设提供理论支撑. 研究结果表明：与其他储换一体站模式相比,储换一体站投资收益率提高 1.51%～2.26%;基于双层规划的容量优化配置方法,在保证一体站经济性的同时,能够对支撑电网电压,使电压日方差降低 20%;随着参与换电的电动汽车数量增加,一体站的经济性进一步提高. 相似文献
90.
近年来,我国经济迅速发展,国民生活水平不断提高。但是在发展经济的过程中,没 有正确认识到保护环境的重要性,汽车数量的增加,导致尾气等污染物给大气带来了严重破 坏。随着我国社会的环境压力不断增加,人们开始意识到保护环境的重要性,积极响应国家 的相关环保政策。而新能源汽车的出现则很好地缓解了汽车尾气对于大气的污染,为环境保 护提供了一种新的途径。文章根据新能源汽车的概念开始分析,探讨目前新能源汽车存在的问题,为提高新能源汽车的管理水平进行深入思考。 相似文献