The attraction of countryside sites

The distribution of car trips to countryside sites, though primarily dependent upon accessibility, is also a function of the site attraction. This paper describes an attempt to assess attraction in numerical terms drawing upon techniques used by the geographer and the transportation planner. It is based on a behavioural model in which excursion rates and travel times of visitors to countryside sites were obtained by questionnaire surveys in the West Midlands region.

A method is established for determining sequentially the relative attraction of pairs of sites through plotting excursion rate ratios and the respective travel time ratios for common visitor origins; therefrom, for a travel time ratio of unity, the relative excursion rates can be found. Further investigation suggested that site extensiveness contributes to attraction in proportion to the square root of the area. Relative intrinsic attractiveness—essentially land form and mantle—can be determined using a points scoring system. These two components when combined with the accessibility component enables a site distribution factor to be obtained.

The application of distribution factors is demonstrated in relation to an existing attractor system and one origin zone; the effects of the introdction of a new site into this system is postulated; both cases above having real life parallels. Agreement between observed and synthesized excursion rates was within the range ±10 to 20 percent.     

氢燃料在铁道车辆的应用前景

以英国IC225车队为例,分析了氢燃料在铁道车辆上应用的技术要求,概述了氢燃料列车设计的可行性,并预测其在铁道车辆的应用前景.     

Local public support for an innovative transit system

Little is known about the sources of public support for transit systems even though the perceptions of transit users and potential users have been extensively documented. Research reported here examines dimensions of public support for the first U.S. downtown people mover during three critical phases in the system's life: construction, shakedown, and operations. The method employed was a community sample survey with home interviews. Data analysis showed that the public—who were virtually all nonusers—were largely favorable toward the system during the construction phase. During the shakedown phase, when system reliability was extremely low, many attitudes toward the system became less favorable, especially perceptions of performance and direct community impacts. Later, reliability improved, and attitudes which had become less favorable tended to grow more favorable once again. It is suggested that a system's performance can influence many aspects of public support for a transit system, even among nonusers. This pattern has implications for system planners who must depend on public good will for continuing support of transit systems. In particular, extensive pretesting of new systems should occur before the fare gates are opened to patrons.     

Lights, camera and acoustics: Assessing macrobenthic communities at a dredged material disposal site off the North East coast of the UK

This study presents the results of a trial assessment based on a combination of sampling techniques at a dredged material disposal site located off the North East coast of the UK, over 2001 to 2004. The site was surveyed with a high-resolution sidescan sonar system producing a mosaic with 100% coverage of the survey area. Benthic communities and sediments were ground-truthed using a Hamon grab with a video camera. Additionally, the area was also sampled in 2003 with a Sediment Profile Imaging (SPI) camera, which complemented other techniques by providing in situ information on sediment quality, and biogenic activities. An assessment is made of the benefits of combining the results from conventional methods, principally using grab samples, with those from acoustic techniques and optical imaging devices to determine seafloor and macrobenthic conditions. This information has the potential to contribute to the enhancement of routine monitoring programmes within UK waters.     

Climate Change and Coastal Management Decisions: Insights from Christchurch Bay,UK

The integration of climate change adaptation considerations into management of the coast poses major challenges for decision makers. This article reports on a case study undertaken in Christchurch Bay, UK, examining local capacity for strategic response to climate risks, with a particular focus on issues surrounding coastal defense. Drawing primarily on qualitative research with local and regional stakeholders, the analysis identifies fundamental disjunctures between generic concerns over climate change and the adaptive capacity of local management institutions. Closely linked with issues of scale, the problems highlighted here are likely to have broad and continuing relevance for future coastal management elsewhere.     

Active Railway Suspensions: Implementation Status and Technological Trends

The paper provides a comprehensive survey of active railway suspensions, covering both basic concepts and significant practical implications around the world. A critical review of technological opportunities, both current and future, is included, and the final section takes a speculative look at long term trends.     

Control and monitoring for railway vehicle dynamics

Over the last twenty to thirty years, railway vehicle dynamics has changed from being an essentially mechanical engineering discipline to one that is increasingly starting to include sensors, electronics and computer processing. This paper surveys the application of these technologies to suspensions and running gear, focused upon the complementary issues of control (which has been reviewed within Vehicle System Dynamics previously) and monitoring (which has not previously been reviewed). The theory, concepts and implementation status are assessed in each case, from which the paper identifies the key trends and concludes with a forward look at what is likely to develop over the next years.     

城市环境中共享（街道）空间概念演变综述

通过综述城市设计与交通工程学科文献,从新西兰视角明确共享空间概念的起源和演变。综述过程包括研究公众期望变化背景下的公共道路空间的功能与使用以及如何与一些相互关联的街道设计方法(如交通稳静化和自适应道路)联系起来。这些方法从机动车时代初期就被用于最小化机动车影响。应用于城市活动中心的公共道路环境中的共享空间概念,正逐渐被城市规划师、交通工程师和管理部门所接受。共享空间不同于传统道路,它鼓励通过少量物理隔离使全体道路使用者合理地使用同一道路空间。为了以安全有效的方式实现共享空间,在设计上需要通过促进步行与骑行活动来降低机动车主导性,同时应将道路空间作为场所来利用而非仅仅出于其机动性与可达性目的。基于交通稳静化街道与共享空间在基础概念上的差异,认为共享空间由一些设计要素组成,若缺少这些要素,公共街道将难以对全体道路使用者发挥其真正的共享空间功能。     

The existence, uniqueness and computation of an arc-based dynamic network user equilibrium formulation

In this paper, a dynamic user equilibrium traffic assignment model with simultaneous departure time/route choices and elastic demands is formulated as an arc-based nonlinear complementarity problem on congested traffic networks. The four objectives of this paper are (1) to develop an arc-based formulation which obviates the use of path-specific variables, (2) to establish existence of a dynamic user equilibrium solution to the model using Brouwer's fixed-point theorem, (3) to show that the vectors of total arc inflows and associated minimum unit travel costs are unique by imposing strict monotonicity conditions on the arc travel cost and demand functions along with a smoothness condition on the equilibria, and (4) to develop a heuristic algorithm that requires neither a path enumeration nor a storage of path-specific flow and cost information. Computational results are presented for a simple test network with 4 arcs, 3 nodes, and 2 origin–destination pairs over the time interval of 120 periods.     

An alternative to FASTSIM for tangential solution of the wheel–rail contact

In most rail vehicle dynamics simulation packages, tangential solution of the wheel–rail contact is gained by means of Kalker's FASTSIM algorithm. While 5–25% error is expected for creep force estimation, the errors of shear stress distribution, needed for wheel–rail damage analysis, may rise above 30% due to the parabolic traction bound. Therefore, a novel algorithm named FaStrip is proposed as an alternative to FASTSIM. It is based on the strip theory which extends the two-dimensional rolling contact solution to three-dimensional contacts. To form FaStrip, the original strip theory is amended to obtain accurate estimations for any contact ellipse size and it is combined by a numerical algorithm to handle spin. The comparison between the two algorithms shows that using FaStrip improves the accuracy of the estimated shear stress distribution and the creep force estimation in all studied cases. In combined lateral creepage and spin cases, for instance, the error in force estimation reduces from 18% to less than 2%. The estimation of the slip velocities in the slip zone, needed for wear analysis, is also studied. Since FaStrip is as fast as FASTSIM, it can be an alternative for tangential solution of the wheel–rail contact in simulation packages.