Shifting from car to active transport: A systematic review of the effectiveness of interventions

IntroductionA promising way to stimulate physical activity is to promote the choice for active modes of transport (walking and cycling). Over the past years, several interventions and policies have been implemented to stimulate this mode shift. However, information concerning the effectiveness of these interventions and policies is still limited. The aim of the present study was to systematically review the effectiveness of interventions designed to stimulate a shift from car use to cycling or walking and to obtain insight into the intervention tools that have been used to promote and/or implement these interventions.MethodsFive databases were searched and articles published in English, Dutch, German, Danish, Norwegian and Swedish were included. Only studies that focussed on a mode shift from car use towards active transport in a general adult population, which were published in peer reviewed journals and which investigated effectiveness were included. Intervention tools used were categorized by using the model of Hoogerwerf & Herweijer, as either legal, economic (subsidy, reward system, penalty), communicative (written materials, behavioural tools) and physical tools (providing bicycles, providing better bicycle facilities at work, adjustment of the environment).ResultsNineteen studies met our inclusion criteria. Studies included described work-place-based interventions, architectural and urbanistic adjustments, population-wide interventions, and bicycle-renting systems. Nearly all studies (except three) showed positive effects concerning a mode shift. Most of the included studies used more than one intervention tool and the tools used differed between types of interventions. However, information about the statistical significance of these results was often lacking and the study methodologies used were not of high quality.ConclusionNearly all studies showed results in a positive direction. However, the quality of the included studies was mostly low and intervention characteristics were poorly described.     

A survey on planning semi-flexible transit systems: Methodological issues and a unifying framework

When demand for transportation is low or sparse, traditional transit cannot provide efficient and good-quality service, due to its fixed structure. New transportation alternatives are therefore increasingly proposed, combining on-demand service adjustment capabilities to the regular route and schedule characteristics of traditional transit. Such so-called semi-flexible systems require careful planning, but no formalization of the corresponding decisions problems, nor any comprehensive methodology has been proposed yet. This paper aims at contributing to fill this gap by presenting a comprehensive literature review, and a general and unifying modeling framework for representing and planning semi-flexible systems. The latter takes the form of the Demand Adaptive Systems, which generalizes the semi-flexible systems described in the literature, and also offers a number of advanced features, the scheduling mechanism, in particular. The paper then provides a classification of planning decisions, which is used to structure a comprehensive and comparative literature review of the field of semi-flexible systems, including methodological contributions as well as a number of particularly significant practical experiences.     

渝怀铁路系统主要设计因素初步评价

研究目的：铁路系统设计因素可以预测拟建铁路系统能否满足决策者的预期目标，因此有必要对拟建铁路系统设计因素开展评价。本文试图探讨铁路系统设计因素的评价办法，对渝怀铁路技术设计状态的主要设计因素做出初步评价。 研究方法：铁路是复杂系统，铁路系统设计因素评价方法很多。本文按照系统思路研究拟建铁路系统设计因素的评价方法。 研究结果：对渝怀铁路设计因素的初步评价表明，在当时已给定条件下，渝怀铁路设计因素是满意的。 研究结论：拟建铁路主要设计因素分析方法是实现预测拟建铁路系统能否满足决策者预期目标的方法之一，有发展前景。     

城市路网交通流元胞自动机模型研究

研究城市路网交通流的动态特性,揭示交通拥堵、环境污染和交通事故的产生原因和规律,能为城市交通问题的解决提供理论依据.元胞自动机模型是研究城市路网交通流动态特性的一个有效工具,能够再现许多重要的交通流特征.从路段模型、交叉口模型和路网模型3个方面总结和评述了国内外各种典型交通流元胞自动机模型.在现有模型的基础上,通过对车辆起讫点分布、路径选择行为、双向通行多车道路段车辆换道规则、不同控制交叉口的车辆更新规则以及网络拓扑结构等方面进行改进,可以提高元胞自动机模型在城市路网交通流仿真中的真实性.     

国际集装箱运输市场回顾及展望

2005年的国际航运市场总体发展相对良好,就国际集装箱运输市场而言,2005年市场发展的主要特点表现为:世界经济稳步增长,市场供需情况良好,箱货贸易量与运力投放量同步上升,市场运价高位整理,船公司收益普遍增长,租船市场依旧抢手,中国因素成为世界海运的核心动力。展望2006年,虽然存在许多不确定因素,但出现重大突发性事件的可能性较小,预计国际集装箱运输市场有望继续处于强势发展周期。     

国际干散货运输市场回顾与展望

从5个方面对2002年的干散货运输市场进行总体分析预测,同时整理归纳了2002年干散货运输的几大特点。 +     

开关电源的分布式并联均流技术概述

随着大功率和分布式开关电源需求的不断提高,分布式并联均流技术已成为电力电子研究的一个热门问题和发展方向。本文综合阐述了开关电源并联均流技术的应用背景、基本原理、常用方法及其发展趋势。     

Air transport and economic growth: a review of the impact mechanism and causal relationships

ABSTRACT

The impacts of air transport on the economy arise both directly, via activity in the aviation sector; and indirectly, via increased spending and wider economic benefits associated with improved access to resources, markets, technology and economic mass. Economic activity, in turn, supports and generates demand for air transport. Despite its potential importance, the reciprocal nature of the causal relationship between air transport and economic performance has remained somewhat understudied. This paper provides a synthesis review of the channels the aviation sector interacts with regional economy. The review focuses on quantitative studies that contribute to the state-of-the-art understandings of the causality. We find that the reciprocal causal relationship is more likely to prevail in less developed economies. For more developed economies, only one direction of the causality is recognised, which runs from air transport to economic growth. Especially substantial is the effect of airline enplanement on service-related employment. The reverse direction of the relationship is, however, not as significant as believed in a causal sense within the developed world. Therefore, cautions need to be taken when applying income elasticities (such as the elasticity of air passenger demand with respect to GDP) in air travel demand forecasting, which implicitly assumes that economic growth causally leads to air traffic increment. Based on the fundamental links between air transport and economic growth, some typical imperfections and inefficiencies in aviation markets are discussed and promising avenues for future research are proposed.     

预制拼装桥墩体系及其抗震性能研究进展

预制拼装桥墩体系(Pre-fabricated Concrete PierSystem, PCP)抗震性能是影响其推广、应用的关键。为加快PCP在中、高烈度等复杂恶劣工程环境中的设计、施工与建造，首先综述了PCP节点连接的接缝形式、连接构造类型及典型工程示例，指出了PCP常用3种接缝形式和6种连接构造力学性能的研究现状及其优缺点；其次，系统地梳理了PCP抗震性能的研究进展，分析了不同连接条件下PCP的抗震性能，明晰了现有PCP抗震性能研究的不足及未来研究方向；最后，详细地论述了PCP抗震性能提升方法的研究前沿，探究了耗能延性构造的设置、高性能材料的应用、新型装配式节点构造设计以及新型混合预制桥墩体系的提出等PCP抗震性能提升方法的优缺点和发展方向。结果表明：通过对装配式节点的合理设计以及薄弱区域的预处理，预制拼装桥墩体系的抗震性能能够达到“等同现浇”的设计原则。然而PCP在复杂恶劣工程环境中的推广应用仍面临以下关键问题：PCP既有节点连接方式、体系和改进措施的抗震性能研究成果亟需归纳；新型节点连接方式、新体系和新型改进措施亟待提出，相关抗震性能有待验证；既有和新型PCP抗震性能的理论分析及抗震设计方法尚需完善；适用于复杂恶劣环境的预制拼装桥墩设计、施工标准亟需制定。     

The built environment and travel behavior in urban China: A literature review

Interests in studying of the built environment impacts on travel behavior have proliferated from North America to other parts of the world including China. Until very recently, there has been very little research into travel behavior in China. However, during the last decade, there has been a fast growing interest in studying the built environment and travel behavior in Chinese cities, perhaps motivated by China’s unprecedented urbanization and rapid urban transport development. Case studies from China provide new insights into the impacts of built environment on travel behavior that can help to enrich existing scholarship. However, currently there is a generally poor understanding of the role played by Chinese research and how it has enriched the international literature. This paper aims to fill this gap by reviewing studies in and outside China by both Chinese and non-Chinese scholars. The focus is on the contribution of these studies to the international literature. We identify four areas of contribution: how the built environment has been developed and its implications for travel behavior; the importance of housing sources in defining residential built environment and explaining travel behavior; the unique Danwei (or work unit) perspective on jobs-housing relationships and commuting behavior; and the importance of neighborhood types in explaining travel behavior in Chinese cities. The findings from this review should be relevant for researchers interested in developing future studies that will further advance geographic knowledge of the built environment and travel behavior, specifically in China and with broader global contexts.