“Turn on the radio,bust out a song”: the experience of driving to work

Though driving to and from work has become a prevalent experience in the lives of individuals in every metropolitan region in the US, much remains to be learned about the activity from the perspective of the drivers. To increase our understanding of the motivation for certain travel behaviors, we must first know something about what those drivers experience. The existing literature explains much, but the application of new methodologies could improve our ability to explain the willingness of individuals to choose to drive through increasingly congested road networks. The results of this study of oral histories of 12 women commuters underscore the idea that commute should be seen as a set of subjective behaviors that contradict some existing assumptions about why individuals commute.     

Threshold controlled scheme of difference expansion techniques for reversible watermarking

Since Tian Jun proposed the difference expansion embedding technique, based on which, many reversible watermarking techniques were proposed. However, these methods do not perform well when the payload is high. In this paper, we proposed an expandable difference threshold controlled scheme for these three methods. Experiments show that our scheme improves the performance of these three methods for heavy payload.     

Why are work travel plans effective? Comparing conclusions from narrative and meta-analytical research synthesis

Reliable research synthesis is of high significance for a transport policy which tries to base its decisions on available empirical evidence. There is growing doubt whether the frequently used narrative approach provides a scientifically defensible way of synthesising a body of quantitative research results. The present paper demonstrates meta-analysis as a more objective and powerful alternative for this task. For this purpose evaluation data synthesised in two earlier narrative reviews on the effectiveness of work travel plans [Cairns et al. Making travel plans work: research report (former), Department for Transport, Local Government and the Regions (DTLR), London, 2002; Smarter choices—changing the way we travel. (Final report of the research project: The influence of soft factor interventions on travel demand. Research report for the Department for Transport.) London. Retrieved 1 December 2005, from , 2004] are meta-analytically re-analysed and compared with the conclusions drawn from the narrative synthesis of these data. Our meta-analyis provides only limited support for the conclusion that addressing parking is the hallmark of successful work travel plans. Our meta-analysis indicates that site and organisational factors as well as characteristics of the monitoring process are significant predictors of effective work travel plans, whereas Cairns et al. view little evidence for the impact of these factors.     

Guidelines for samplers: measuring a change in behaviour from before and after surveys

This paper addresses the issue of using before and after surveys to evaluate behavioural changes in response to transport policies and investments, a procedure that, we argue is done far too rarely in this profession. Further, it demonstrates very clearly that, in almost all conceivable cases, there are considerable economies to be obtained by using a panel (again, under-utilised in our profession) to undertake evaluation, rather than successive independent cross-sectional surveys. The paper also addresses the critical issue of sample size requirements for measuring changes of a relatively small magnitude in travel behaviour; i.e., to state, with 95% confidence, that if there is a ∂ percent change in behaviour for the sample, there is a ∂ percent ± e percent change in the behaviour of the population, where e is the sampling error. In this paper, we present a method for calculating such sample size requirements from first principles and demonstrate the applicability both hypothetically and then empirically using data from the Puget Sound Transportation Panel. The formulation enables designers of before and after surveys to investigate the trade-offs between the statistical accuracy of their predictions and the sample size requirements systematically, without the need to specify ∂ a priori. This latter point is crucial, we argue, because we have limited information on ∂, yet, as we explain here, it drives the sample size requirements using alternative, well-cited approaches for calculating sample sizes to assess behavioural change. The results have important ramifications both for those implementing transport policies intended to produce behavioural change, especially when a cost-benefit evaluation of the policy is desired, and for those interpreting the results reported in previous studies.     

Influences on bicycle use

A stated preference experiment was performed in Edmonton in Canada to both examine the nature of various influences on bicycle use and obtain ratios among parameter values to be used in the development of a larger simulation of household travel behaviour. A total of 1128 questionnaires were completed and returned by current cyclists. Each questionnaire presented a pair of possible bicycle use alternatives and asked which was preferred for travel to a hypothetical all-day meeting or gathering (business or social). Alternatives were described by specifying the amounts of time spent on three different types of cycling facility and whether or not showers and/or secure bicycle parking were available at the destination. Indications of socio-economic character and levels of experience and comfort regarding cycling were also collected. The observations thus obtained were used to estimate the parameter values for a range of different utility functions in logit models representing this choice behaviour. The results indicate, among other things, that time spent cycling in mixed traffic is more onerous than time spent cycling on bike lanes or bike paths; that secure parking is more important than showers at the destination; and that cycling times on roadways tend to become less onerous as level of experience increases. Some of these results are novel and others are consistent with findings regarding bicycle use in work done by others, which is seen to add credence to this work. A review of previous findings concerning influences on cycling behaviour is also included.     

台湾海底隧道之接头与管段变化研析及对策

台湾唯一之海底隧道系采沉埋方式施工,该隧道不仅处于具高度盐份腐蚀之不利环境,且位于软弱地盘上.于营运二十余年后,轻微异状已有显现,如管段接头锈蚀、管体渗漏及管体裂损等异状.上述异状可能为接头构件变形、管体变位/变形及结构劣化等影响隧道安全之前兆,甚至降低其耐震能力;因该隧道肩负港区及区域经济发展之运输重任,如何藉由整体性体检进行安全评估及研订适当之维护补强对策,为计划执行重点;故本文将说明隧道接头、结构体等隧道重要构件之检测调查(如地球物理、钢筋腐蚀、裂缝深度、氯离子试验、防蚀电位、接头防水等项目)、数值分析及自动化监测(接缝计、单元沉陷仪、结构倾斜仪、电位计等)等综合评估结果及维护补强对策,以提供工程界日后参考.     

潜盾机在到达井外侧地盘中安全弃壳之案例研讨

捷运潜盾隧道皆位于人口密集之都会区,潜盾机的发进与到达常为潜盾隧道挖掘过程中风险较大的时间点,本研究拟以潜盾机到达弃壳作业为例,探讨其面临之风险,包括点井降水造成地盘地下水位变化和邻近台电345 kV高压电塔不均匀沉陷,以及站体连续壁因开挖所引致侧向变位使JSG地盘改良区产生缝隙水路,造成潜盾机开舱前渗水的风险.再者,依据工址抽降水期间竖管式水压计、水位观测井和地表、建物沉陷点监测数据分析抽降水引致地表沉陷影响范围,用以回馈将来遭遇类似工况的设计参考依据.潜盾机到达之安全弃壳作业包括以超级点井(SWP)工法尝试降低地下水位,并于松三层(EL.92.42m)和松五层(EL.72.42m)埋设竖管式水压计了解降水期间地下水位变化,同时监测邻近建物如台电高压电塔的倾斜及沉陷;其次,在潜盾机到达处先行进行JSG地盘改良,再以试水试验检核地盘止水性,潜盾机到达后即进行机壳背填灌浆、土压舱分阶排土及漏水确认.然后,潜盾机历经二次拆解,完成到达弃壳作业,最后进行镜面破除及隧道贯通.     

Climate change and the future Maritime Policy for the EU

A cross-cutting Maritime Policy can ensure that climate change threats and challenges in regards to seas and oceans are dealt with in a wide policy framework that takes into account the impacts that climate change may have on other sectors and vice versa.     

Basic design of a series propeller with vibration consideration by genetic algorithm

Genetic algorithms (GAs) can powerfully search for parameters in a large multidimensional design space. Thus, the principle can be applied to preliminary series propeller design problems with multiple considerations. In the present study, B-series propeller design was conducted using a GA for both hydrodynamic efficiency and vibration consideration. The objective function was set by users who could freely weight the relative importance of efficiency and vibration. GAs were successfully shown to be able to obtain an optimal set of parameters leading to efficient performance and low vibration.