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831.
Car use in urban areas carries well known risks for negative effects on urban quality of life, the environment and land use. Previous psychological work has mainly studied the habit of using a car as a predictor variable, whereas only a few studies have focused on psychological factors that may underlie and shape the habit. The aim of the present study is to examine demographic characteristics, spatial variables and social–psychological factors associated with car habit use strength. The results are based on a survey conducted in a random urban population-based sample with car access recruited from the Norwegian population registry (n = 878). Car use habit strength was stronger among male than female respondents and tended to be weak with a lower income. Multivariate logistic regression showed that reporting pro-environmental attitudes and personal norms predicted a weak car use habit strength, while reporting strong priority of flexibility and a long distance from home to work predicted a strong car use habit strength. Car use habit is influenced by multiple demographic, spatial and social–psychological factors, which should be carefully addressed in interventions aimed at reducing the likelihood of developing a strong car habit strength. 相似文献
832.
833.
Much local and regional transport policy is attempting to increase cycling as an everyday mode of travel through infrastructure changes, education initiatives, and safety campaigns. While considerable research has examined the influence of the built form on cycling, less research has examined the barriers that prevent people who wish to cycle more (as part of their routine) from doing so. This study examines several factors influencing the frequency by which people do (and do not) cycle in a campus setting in a large metropolitan area. Mixed methods reveal differences between barriers to cycling as well as the relative strength of these barriers across categories of age, sex, and current mode used. A multinomial logit model, which controls for residential self-selection effects, predicts whether and how often a respondent cycles based on socio-demographic and trip characteristics. The presence of cycle paths is found to be strongly associated with a higher frequency of cycling commutes. Additionally, an analysis of stated barriers reveals effort and a lack of safety as the most important barriers to potential cyclists. Finally, a qualitative analysis of respondents’ open-ended responses confirms the influence of bicycle paths, but reveals other factors such as the importance of improved interactions among various street users. Findings from this research can be of benefit to transportation engineers and planners who are aiming to increase the use of cycling among various groups of commuters. 相似文献
834.
In the quest for sustainable travel, short distances appear the most amenable to curbing the use of the automobile. Existing studies about short trips evaluate the potential of shifting from the automobile to sustainable travel options while considering the population as homogeneous in its preferences and its tendency to accept these alternative travel options as realistic. However, this assumption appears quite unrealistic and the current study offers a different perspective: the mode choices when travelling short distances are likely related to lifestyle decisions. Short trip chains of a representative sample of the Danish population in the Copenhagen Region were analysed, and more specifically a latent class choice model was estimated to uncover latent lifestyle groups and choice specific travel behaviour. Results show that four lifestyle groups are identified in the population: car oriented, bicycle oriented, public transport oriented and public transport averse. Each lifestyle group has specific perceptions of travel time (with extremely different rates of substitution between alternative travel modes), transfer penalties in public transport trip chains, weather influence (especially on active travel modes), and trip purpose effect on mode selection. Consequently, when thinking about measures to increase the appeal of sustainable travel options, decision-makers should look at specific individuals within the population and more sensitive individuals to comfort and level-of-service improvements across the lifestyle groups. 相似文献
835.
撞击参数对双层舷侧结构碰撞响应的影响 总被引:8,自引:1,他引:7
深入了解船体结构碰撞损伤特性和能量吸收机制是开展船舶耐撞性优化设计的前提。文章利用显式非线性有限元数值仿真技术对不同撞击条件下的双层舷侧结构碰撞响应进行了系列研究。研究结果表明:撞击位置、撞击角度和撞击速度的改变可能导致不同的碰撞损伤过程或结构损伤变形。 相似文献
836.
当前浮式平台船体结构分析的方法与重点综述(英文) 总被引:2,自引:0,他引:2
浮式平台概念的选择及其结构设计是深水工程项目的关键环节之一.它决定了平台在波浪载荷作用下的动力学响应、立管在深水条件下的运动以及进行平台建造与安装的技术难度等.结构强度、结构的抗疲劳性能以及结构的整体和局部稳定性能是浮式平台设计必须重点考虑的三个主要方面.总结了当前浮式平台设计的主要方法和它的主要任务以及技术要求,着重分析了设计过程中的主要技术难点及重点;最后,讨论了浮式平台结构设计的潜在发展趋势. 相似文献
837.
838.
SART标准修改对海上搜救的影响 总被引:1,自引:0,他引:1
SART是GMDSS的重要组成部分,对海上搜救发挥了关键作用.随着AIS的广泛应用,IMO对GMDSS的标准进行了修改,在原来RADAR-SART的基础上,增加了AIS-SABT.AIS-SART的实施有利于海上搜救,同时对AIS船舶的识别码管理提出了新的要求. 相似文献
839.
840.