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81.
Single policies or entire policy packages are often assessed using different methods aiming at a quantification of effects as well as the detection of undesired outcomes. The knowledge of potential impacts is essential to take informed policy actions. Hence, there is a constant need for efficient assessment approaches to support policy decision-making. A broad range of such assessment methods is used in policymaking. Some of them are using quantitative data; others are characterized by qualitative information, observations or opinions. Practical experiences with transport policy prove that these methods all have their pros and cons, but none of them are able to detect the full range of effects. This leads to important questions this article deals with, such as what are the strengths and limitations of the different tools and methods for assessing impacts, and how should different approaches be integrated into the policymaking processes?We analyze the ability of assessment methods to detect different kinds of intended and unintended effects, and introduce the concepts of structurally open (mainly qualitative) and structurally closed (mainly quantitative) methods. It is argued that these concepts support making the pros and cons of the tools and methods more explicit and, thus, allow integrating the different tools and methods into the process of policy packaging. Based on a policy package example, we provide practical recommendations on how to integrate different assessment methods adequately and show that both quantitative and qualitative tools should be used in different phases of the process. The main recommendation is to alternate the application of assessment methods with structurally open methods used in the beginning and the end of the policymaking process and applying structurally closed methods in between.  相似文献   
82.
公交场站设施是重要的城市基础设施.本文重点探讨城市公交场站设施规划建设方面的一些问题,包括公交场站发展的规模、场站规划设置标准、场站建设模式等,并提出了相关的意见和建议.  相似文献   
83.
ABSTRACT

Transport network criticality analysis aims at ranking transport infrastructure elements based on their contribution to the performance of the overall infrastructure network. Despite the wide variety of transport network criticality metrics, little guidance is available on selecting metrics that are fit for the specific purpose of a study. To address this gap, this study reviews, evaluates and compares seventeen criticality metrics. First, we conceptually evaluate these metrics in terms of the functionality of the transport system that the metrics try to represent (either maintaining connectivity, reducing travel cost, or improving accessibility), the underlying ethical principles (either utilitarianism or egalitarianism), and the spatial aggregation considered by the metrics (either network-wide or localised). Next, we empirically compare the metrics by calculating them for eight transport networks. We define the empirical similarity between two metrics as the degree to which they yield similar rankings of infrastructure elements. Pairs of metrics that have high empirical similarity highlight the same set of transport infrastructure elements as critical. We find that empirical similarity is partly dependent on the network’s topology. We also observe that metrics that are conceptually similar do not necessarily have high empirical similarity. Based on the insights from the conceptual and empirical comparison, we propose a five-step guideline for transport authorities and analysts to identify the set of criticality metrics to use which best aligns with the nature of their policy questions.  相似文献   
84.
Sri Lanka has an extensive Three-Wheeler Taxi service comprised of around 300,000 vehicles. These vehicles, which first made an entry to Sri Lanka’s roads in the early 1980s, account for around 15% of the active motor vehicle fleet at present. Three-Wheelers Taxis also account for around 6% of the passenger kilometres. These vehicles are mostly individually operated with some owned by the operator and others hired on a monthly or daily basis. The industry is unregulated with vehicle registration and driving licenses being the only instruments of regulation. Fares are unregulated. However, most operators belong to associations which are loose collections of operators found in a given locality. These associations impose a degree of self regulation with respect to fares. They also tend to demonstrate oligapolistic behaviour.The paper is based on a survey of 200 operators and 100 passengers from a Divisional Secretariat area in Colombo District. The survey covered a number of details pertaining to ownership, management and fare structures, as well as opinions on the service attributes by users. The survey also covered perceptions of operators to determine the social, economic and transport implications of the services provided. Details were also obtained on the profiles of the operators and their expectations.The paper provides the results of the analysis of this data and draws a number of conclusions on the economics of the industry as well as the social aspects associated with it. It also discusses the characteristics of the users of these three wheelers as well as their typical use. The analysis also investigates complementarily of service provision between three wheelers as an access mode to buses and railways. This analysis has been used to develop an understanding of the manner in which the industry has grown over the last two decades and how it is being operated today. It also identifies areas wherein the industry has become inefficient and assesses the degree of over pricing that exists due to this. The data also helps to determine the relationship between unemployment and provision of self-employed transport services.The paper concludes with a synopsis of the profile of the industry and its role within the wider transport sector and with respect to ownership. It also discusses the positive and negative impacts of the lack of regulation on the industry.  相似文献   
85.
One main theme of European Union’s in transport policy statements has been the increased role of railways in the reducing environmental impacts and costs of transport activity. One option to increase the modal share of rail transport is to utilize the dry port concept, particularly applicable to general cargo. At the Port of Gothenburg (Sweden) use of this concept in combination with rail transport has led to a reduction of CO2 emissions, and lower transport energy costs. The main objective and motivation of this research work are to examine through analytical models, how this same dry port concept could be implemented in the Finnish transportation network, with estimates of the benefits being gained.The research method of this study is macro gravitational models of distribution. Main input data for the models are distances and population in the area. The approach aims to research, how relative transport costs behave by increasing the number of dry port distribution locations. For the actual computation work the authors apply linear integer programming. Based on the results, the authors argue that relative transport costs can decrease considerably by increasing the number of dry ports, up to the level of six locations. This is considerably less than what is the current situation in Sweden. The found solution also differs from Sweden as the fragmented Finnish seaport system enables using numerous seaports instead of one, which further decreases inland transportation distances and volumes considerably. At the same time forthcoming sulphur emission reduction regulation (for sea transports) might impact the transportation network structure by decreasing sea transport and the number of seaports used. This might lead to a further increase in land-based hinterland transport.  相似文献   
86.
基于小波消噪的ARIMA与SVM组合交通流预测   总被引:3,自引:2,他引:3  
针对实际交通系统时变复杂和变化的不确定性所带来的交通流量非线性和强干扰性的特征,首先应用小波分析方法,对原始交通数据进行了消噪处理,使消噪后的数据更能反映交通流的本质及变化规律;然后采用自回归求和滑动平均(ARIMA)和支持向量机(SVM)的结合预测模型对交通流进行了预测,最后用实测交通数据进行了验证分析,得到了两个结论:一是组合预测模型比单个预测模型的预测精度高;二是小波分析消噪后的组合预测模型比没有消噪的组合预测模型预测精度高.结果表明消噪后的组合预测模型具有较高的预测精度,可用于交通流的实时动态预测.  相似文献   
87.
公路方式是我国枢纽机场与城市衔接的主要交通方式。枢纽机场衔接公路网的优化,能维持该区域客运交通运输网络高效运转,是综合运输体系中的关键技术。我国面临枢纽机场衔接公路网优化理论不完善和经验缺乏的问题。从系统工程角度,分析国内外大型机场地面交通衔接的现状和发展趋势,阐述枢纽机场地面交通衔接集聚特征及集疏运机理,探讨枢纽机场衔接影响因素(制约性、结构性、比例性)和衔接公路网优化准则,提出枢纽机场衔接公路网优化的核心问题和研究方向。  相似文献   
88.
Abstract

Enhancing the bus experience through improved information provision is a key element of UK Government transport policy. Real time passenger information (RTPI) is perceived to reassure waiting passengers, to benefit the bus operator through increased revenue and the local authority, by promoting social inclusion and achieving a modal shift. RTPI also provides an important tool for operators by allowing them to monitor services and refine their schedules.

The aim of this paper is to understand the reasons for implementing RTPI in the bus sector, and to determine the key issues impacting on the likely success of such a policy. A case study approach investigates the experiences of two provincial towns in the UK. The paper suggests that, whilst it is unclear whether RTPI has resulted in an increase in bus patronage, it is considered to be most effective when combined as part of a package of measures. It is intended that the findings from the two case studies will reveal lessons of relevance to authorities contemplating the introduction of RTPI.  相似文献   
89.
文章结合2013年最新出台的《广西壮族自治区船闸管理办法》,以及近期国家关于行政审批制度改革的相关精神和要求,对集装箱班轮优先过闸条款进行探索和研究,分析了集装箱班轮优先过闸面临的主要问题,提出了一套新的市场管理模式,即主要采取企业公开"承诺制",加上"定期、定港、定线、不定船"的管理模式,通过实施"宽进严管",以期在简政放权的同时,能够充分发挥市场作用,促进企业自律,推动内河集装箱班轮运输市场的健康发展。  相似文献   
90.
This study deals, first, with estimation of transport demand based on Genetic Algorithm (GA) approach, and then deals with the evaluation of the road tax system in Turkey. It proposes an alternative road tax policy. The total transport demand is estimated based on population, Gross Domestic Product per Capita (GDPPC), and vehicle-number. Three forms of the Genetic Algorithm Transport Demand Estimation for Tax Revenues (GATDETR) are developed, of which one is linear, and the second and third are exponential forms of the mathematical expressions. The best-fit GATDETR model in terms of total minimum relative average errors between observed and estimated values are selected for future demand estimation. The evaluation of the road tax system and policy proposal is made based on estimated demand. The Distance-Based-Taxation (DBT) system is proposed in order to control highway transport. With the DBT system, some road users may wish to use railway. Thus, we re-organize the railways in order to meet the demand, but this requires new fund. The DBT system may help to create to this fund. It may also help to develop fair-taxation for the road users. Results show that the GA can be used to model transport demand and hence income tax in future transports planning. This study also suggests that planning the taxation in highway transport may help to ease funding problem of railway system.  相似文献   
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