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1.

Transport policy in Korea is driven by the need to cope with ever-worsening traffic conditions. The development of an intelligent transport systems (ITS) Master Plan for Korea is of particular interest and demonstrates the heavy reliance placed on ITS measures to facilitate both the management of congested (but expanding) highway networks and to encourage a shift to greater use of public transport. The paper highlights the major achievements of ITS in Korea by assessing the evidence provided by the widespread implementation of ITS technologies (such as the creation of 'showcase' demonstrations). Some observations from the implementation of ITS in (so-called) transitional economies are presented.  相似文献   

2.
This article presents an overview of highway and transportation planning in England. It covers the division of responsibilities between central and local government; the organisation of the Department of Transport; the planning, financing and implementation of road schemes, both local and national. A very brief review of transport legislation is included.NOTE: This paper was printed before the UK General Election of May 1979. The Department of Transport is now responsible to the Minister of Transport. The Minister has similar responsibilities to those previously exercised by the Secretary of State for Transport as referred to in this paper. The views expressed in this paper are those of the writer and are not necessarily those of the Department of Transport.  相似文献   

3.
Effect of capacity concentration on highway corridor performance   总被引:1,自引:0,他引:1  
This paper investigates, through use of analytical models, the effects of capacity concentration on highway corridor performance. It concludes that when highways operate at a fixed total capacity, decreasing the highway spacing can increase the average travel time because highways will become more congested. When highways operate below capacity, decreasing the spacing is usually beneficial as it tends to reduce trip length when accessing highways, and allows a greater percentage of travel to be completed on highways instead of arterials.  相似文献   

4.

The Dutch National Institute of Public Health and Environmental Protection publishes Environmental Outlooks in which 25‐year projections are made. These Outlooks quantifying the environmental problems, form the scientific basis for Dutch environmental policy. Traffic and transport is one of the main sectors causing environmental problems. The emissions and energy use of all relevant categories (road traffic, non‐road traffic) are based on model simulations with models. This paper describes the main models used.

If present policy is implemented only a minority of the environmental targets will be met.

If a sustainable transport system for the Netherlands means a large reducton in CO2 emissions and energy use after 2010 a stronger emphasis on both technical and non‐technical measures (such as land‐use planning combined with public transport improvements) for the period until 2010 is needed than proposed in the Second Transport Structure Plan, unless a sustainable energy source becomes available.  相似文献   

5.

Addressing the issues of traffic safety in rural areas presents a constant challenge. The mix of light and heavy vehicles and the considerable differences in speed among these traffic participants result in high risks and delays for the faster vehicles. Agricultural vehicles (AVs) in particular have such an impact on traffic, especially when using arterial highways. This paper reviews the problems of safety and delays that AVs cause on arterial highways, and the appropriate mitigation. The concept of 'sustainable safety' in The Netherlands focuses on these problems, because of the proposed construction of parallel roads alongside all arterial highways. However, Dutch accident statistics cannot justify the high costs for the construction of parallel roads alongside 7000 km of arterial highways. Delays experienced by fast traffic are another reason for separating AVs from other road users with parallel roads. Alternative measures alongside the arterial highway, such as passing bays, restricting AVs to travelling at off-peak only and improving the conspicuity of the AVs, may be more cost-effective ways of reducing delays and/or improving traffic safety on arterial highways. Another solution may be to eliminate the need for AVs to use the arterial highway by altering their routes. For this purpose, land reallocation projects (as practised in Holland) can provide a useful tool.  相似文献   

6.
‘Vehicle miles traveled’ (VMT) is an important performance measure for highway systems. Currently, VMT [or ‘annual average daily traffic’ (AADT)] is estimated from a combination of permanent counting stations and short-term counts done at specified locations as part of the Highway Performance Monitoring System (HPMS) mandated by the US Federal Highway Administration. However, on some roadway sections, Intelligent Transportation Systems (ITS) such as detectors and cameras also produce traffic data. The question addressed in this paper is whether and under what conditions ITS systems data could be used instead of HPMS short-term counts (called ‘coverage counts’)? This paper develops a methodology for determining a threshold number of missing daily traffic counts, or alternatively, the number of valid ITS data observations needed, in order to confidently replace the HPMS coverage counts with ITS data.

Because ITS counts, coverage counts, and actual ground counts (e.g. continuous counts) cannot be found coexisting on a roadway section, it is hard to compare them directly. In this paper, the Monte Carlo simulation method is employed to generate synthetic ITS counts and coverage counts from a set of relatively complete traffic counts collected at a continuous count station. Comparisons are made between simulated ITS counts, coverage counts, and actual ground counts. The simulation results indicate that when there are<330 daily traffic counts missing in a set of ITS counts in a year, that is, when there are at least 35 days of valid data, ITS counts can be used to derive a better AADT than using coverage counts. This result is applied to calculate the VMT for the Hampton Roads region in Virginia. The comparison between the VMTs derived with using and not using the threshold number indicates that these two VMTs are significantly different.  相似文献   

7.
Among the crises facing our society is the public's loss of confidence in technical professionals and their ability to make decisions about large-scale projects (such as highways) in the public interest. To overcome this crisis of confidence, this paper hypothesizes a model for the role of the technical professional in the process of reaching decisions about public actions.In evaluating technological projects with social consequences, one key issue is the differential incidence of impacts. Typically, some groups are hurt in order that others may benefit. Social equity must be considered explicitly. Such presently-used techniques as benefit-cost analysis and point-rating schemes are unsatisfactory. New techniques are needed, reflecting a more comprehensive model for the role of the technical team in the political process.A normative model is outlined. First, the objective of the technical process is defined: to achieve substantial effective community agreement on a course of action which is feasible, equitable, and desirable. Second, a process for achieving this objective is proposed. A key element of this process is a four-phase strategy of technical and community interaction activities to achieve the objective. The basic premise of this approach is that the role of the technical team is to clarify the issues of choice, to assist the community in determining what is best for itself.This theoretical model has resulted in several practical products. A procedural guide for use by highway and transportation agencies has been prepared, and a number of specific operational techniques have been developed and are included in the guide. The procedural guide is now being field-tested in several state highway departments. The theoretical model has already been useful in identifying, in one highway department, opportunities for significant changes in the agency's mission, organization and procedures to enable it to be more responsive to public concerns. The theoretical model also has served as the basis for the development of federal guidelines for consideration of social, economic and environmental factors in highway planning and decision-making, in all of the state highway departments in the U.S.This is a revised version of a paper presented to the Seventeenth North American Meeting, Regional Science Association, November 6–8, 1970.  相似文献   

8.
随着节能减排工作的深化和细化,公路基础设施建设的节能减排越来越受到重视。基于全国公路工程造价管理系统和中国生命周期核心数据库,可以快速实现改扩建公路生命周期能耗和碳排放的规范化核算,从而筛选出节能减排效益较优的设计方案。文章通过海南省某省道改扩建项目的实证研究,为设计方案节能减排核算及效益评价提供范例,为优化公路建设行业节能减排管理提供思路。  相似文献   

9.
This paper considers the problem of how to select highway projects for the build-operate-transfer (BOT) development with the objective of improving the social benefit while ensuring the marketability of those selected. The problem can be viewed as a tri-level leader-follower game and is formulated as a mixed integer program with equilibrium constraints. Without solving the associated problem, we show that optimal tolls and travel times on selected BOT highways can be determined from their attributes under mild assumptions. This leads to an efficient heuristic algorithm for solving the project selection problem.  相似文献   

10.
Automated highway systems (AHS) are intended to increase the throughput and safety of roadways through computer control, communication and sensing. In the “platoon” concept for AHS, vehicles travel on highways in closely spaced groups. To maximize benefits, it is desirable to form platoons that are reasonably large (five or more vehicles), and it is also desirable to ensure that platoons remain intact for considerable distances. This paper develops and evaluates strategies for organizing vehicles into platoons at highway entrances, with the objective of maximizing the distance that platoons stay intact, so that they do not need to be regrouped into new platoons on the highway itself. Fundamentally, this entails grouping vehicles according to their destination. We evaluate various strategies in which vehicles are sorted on entrance ramps, with respect to platoon sizes, throughput and platoon formation time.  相似文献   

11.
This paper presents a multidimensional examination of the infrastructural, technical/technological, operational, economic, environmental, social, and policy performance of the future advanced Evacuated Tube Transport (ETT) system operated by TransRapid Maglev (TRM) (the ETT-TRM system). The examination implies analyzing, modeling, and estimating selected performance criteria using the case of the Trans-Atlantic passenger transport market currently served exclusively by the Air Passenger Transport (APT) system. The purpose is to assess the ETT-TRM system’s competitive capabilities compared to those of the current and future APT system and consequently its potential contribution to mitigating impacts of both systems on society and the environment – the sustainability of the transport sector - under given conditions.  相似文献   

12.
高智 《交通节能与环保》2021,17(2):95-97,100
为推动公路建设水平,确保公路正常运营和沿线生态环境可持续发展,文章总结了公路绿化的特点和功能,从安全性、经济性、生物多样性、景观性等方面分析了公路绿化设计的原则,并探讨了公路中央分隔带、路基边坡、互通立交、服务区的绿化设计内容,从公路环保的重要性,认知公路环保的内容、功能及意义,并多方角度的加以分析和采取措施,达到预期效果,把建设和环境紧密协调统一。并对公路环保的设计理念、评价指标、评价方法及施工阶段的环保措施进行了论述。  相似文献   

13.
High-speed rail is often touted as a means to reduce congestion on the United States’ highways by removing passenger car traffic. But highway congestion can also be reduced by reducing the amount of freight traffic. So, given the advances in high-speed rail, the potential exists for developing a national high-speed network for freight distribution. To design such a network considering highway traffic and transit times, we present an uncapacitated network design model with a post-processing step for the capacity constraint. To illustrate how our modeling approach could be used by policy makers to evaluate the impacts of a high-speed rail network, we apply our models with preliminary data on high-speed rail operating parameters for freight applications and from current data on shipments from a major truckload carrier and the US Census Bureau.  相似文献   

14.
ABSTRACT

This paper measures the performance of taxi operators using data envelopment analysis (DEA) and the improvement of performance based on benchmarks. This includes basic DEA models and a cross efficiency model. In the present work, a sample set of 20 taxi operators are considered, and an evaluation indicator framework is constructed, which mainly involves the identification of decision-making units (DMUs) and the determination of input-output variables. The combined results of multiple DEA models are used to evaluate the performance of taxi operators in a case study of Harbin. The results highlight the significance of the combined application of multiple DEA models, especially a cross-efficiency model that can obtain more objective efficiency values. Finally, the benchmarking method is used to capture the achievements of best-performing operators and provide valuable improvement recommendations for inefficient operators. Conclusions provide a suitable basis for the operation and management of the taxi market.  相似文献   

15.
Vehicular Ad-Hoc Networks (VANETs) are an emerging technology soon to be brought to everyday life. Many Intelligent Transport Systems (ITS) services that are nowadays performed with expensive infrastructure, like reliable traffic monitoring and car accident detection, can be enhanced and even entirely provided through this technology. In this paper, we propose and assess how to use VANETs for collecting vehicular traffic measurements. We provide two VANET sampling protocols, named SAME and TOME, and we design and implement an application for one of them, to perform real time incident detection. The proposed framework is validated through simulations of both vehicular micro-mobility and communications on the 68 km highway that surrounds Rome, Italy. Vehicular traffic is generated based on a large real GPS traces set measured on the same highway, involving about ten thousand vehicles over many days. We show that the sampling monitoring protocol, SAME, collects data in few seconds with relative errors less than 10%, whereas the exhaustive protocol TOME allows almost fully accurate estimates within few tens of seconds. We also investigate the effect of a limited deployment of the VANET technology on board of vehicles. Both traffic monitoring and incident detection are shown to still be feasible with just 50% of equipped vehicles.  相似文献   

16.
Economic development is increasingly used by state DOT's as a criterion in arriving at highway funding decisions. However, there exists little evidence in the literature justifying the use of such a criterion, especially since existing techniques only determine correlations between highways and development. In this paper a time-series methodology is developed to differentiate the effects of highways on development from the effects of development on highways. This methodology includes structural plot analysis and causality tests and is based on pooled time-series and cross-sectional data on highway construction expenditures and county employment. The results indicate that increases in highway expenditures do not, in general, lead to statewide increases in employment other than temporary increases in the year of construction. However, in counties that are economic centers of the state, highway expenditures do have a positive long-term effect, i.e. employment increases above the normal trend of the economy. Such gains are apparently counterbalanced by employment losses in counties adjacent to the economic centers.  相似文献   

17.
Aiming at the problems in the highway runway clearance condition evaluation, according to the improved obstruction requirement of highway runway, the inner transitional surface (ITS) and outer transitional surface (OTS) range are calculated and analyzed in detail, the shape range of the ITS and OTS is pointed out, the methods of calculating the intersecting line and the key various points among ITS, runway strip (RS), inner horizontal surface (IHS) in terminal clearance zone (TCZ), including among OTS, IHS and outer horizontal surface (OHS) in side clearance zone (SCZ) are put forward. Furthermore, obstruction requirement when aircraft are placed on apron of the near highway sections is considered, then the corresponding steps of evaluation are proposed. The procedural design of highway runway clearance condition evaluation is realized by means of software to program. The superelevation condition of the obstacle in the clearance of the highway runway is calculated and analyzed by actual examples. All these have provided a theoretical basis for exactly determining the position, altitude and the superelevation value of the obstacle in the highway runway clearance zone.  相似文献   

18.
This paper presents a multi-criteria model to rank highway projects by predicting their combined potential impact on regional population, economy, environment, territory and mobility. A detailed study of initial conditions enable the selection of functional units of study and the identification of homogenous units within the region, playing a relevant role into the process. Ranking is based on the achievement of both efficiency and cohesion objectives at a regional level. The model is tested by analyzing the Spanish Transport Infrastructure Master Plan (PEIT) for the non-central area of Northwest Spain. Application of impact assessment shows that the construction of infrastructures has selective effects in the area according to the homogenous groups. Potential development was boosted in one of the zone groups, whereas in others, at best, there was a reduction in their regressive tendency. Finally, the model is a dynamic support tool that could be adapted to several planning policies only when the ranking criterion is well-justified.  相似文献   

19.
Park and ride facilities on light rail transit systems   总被引:2,自引:0,他引:2  
There is now considerable interest in exploring the idea of strategic park and ride as a means of promoting the use of rail transit and encouraging a transfer of commuters from car to public transport. This is especially evident in North America, where extensive park and ride facilities have been installed on a number of light and heavy urban rail systems. There is a general consensus about the most suitable types of location for facilities, but less agreement on the development of a reliable method of forecasting demand and also on the required size of sites. Experience in practice indicates that although park and ride is attractive to commuters, schemes do not generally result in lasting reductions in highway congestion, due to rising car ownership and use and the phenomenon of generated traffic.Abbreviations Centro West Midlands Passenger Transport Executive - K&R Kiss and ride - LRT Light Rail Transit - PT Public Transport - RT Rapid Transit - TRRL Transport & Road Research Laboratory, UK  相似文献   

20.
江西省永修至武宁(庐山西海)高速公路(以下简称庐山西海高速公路)被批准为交通运输部“安全绿色高速公路科技示范工程”,沿线旅游资源丰富。文章从旅游公路的功能和景观特性分析着手,基于文化与公路景观的关系,调研分析了庐山西海高速公路旅游文化景观资源分布情况,提出公路人文景观规划应重点提取当地的人文信息、旅游特色及佛教文化资源加以应用,并对部分设计案例和实施效果进行了介绍。  相似文献   

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