基于 matlab的边坡虹吸排水渗流场分析

地表降雨入渗会引起边坡地下水位的上升，进而降低边坡的稳定性，因此降低地下水位对增加边坡的稳定性极其重要。虹吸排水是一种免动力并且能排除坡体深部地下水的措施，利用 matlab优越的求解能力对虹吸排水后边坡内的地下水浸润曲线分布进行研究来寻求相对合理有效的虹吸排水孔位置，研究过程中对虹吸排水采用近似的点汇来处理，比较接近实际的工程。研究的结果表明浅部排水孔适合边坡应急而深部排水孔可以有效提高边坡长期稳定性和缓冲下一次降雨引起的边坡地下水位抬升，可为实际工程提供参考。     

Understanding cyclists’ perceptions,keys for a successful bicycle promotion

Many variables that influence bicycle use beyond time and cost have been included in models of various types. However, psycho-social factors that make the bicycle eligible as a modal alternative have not been identified properly. These factors are related to intention, attitudes and perceptions, and their identification can contribute to obtain the keys for a successful bicycle policy. Here, an in-depth investigation of cyclists’ perceptions is attempted using a large university survey designed and collected ad hoc, and then applying exploratory and confirmatory factor analyses. After identifying fourteen factors, a structural equations model was estimated to find structure and relationships among variables and to understand users’ intentions to use the bike. Four (latent) variables are identified, namely convenience, pro-bike, physical determinants and exogenous restrictions. The main conclusion is that convenience (flexible, efficient) and exogenous restrictions (danger, vandalism, facilities) are the most important elements to understand the attitudes towards the bicycle.     

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.     

Technical standardization of ITS and Asian initiatives for intelligent mobility

User-centric intelligent mobility businesses emerge and prosper in Asian metropolitan areas by utilizing the progress if information and communication technology (ICT). Under the rise of private lead initiatives on intelligent transport systems (ITS), the roles of public sectors are still large. Public sectors should precisely identify the extensive ITS services by considering the regional conditions and deploy them by collaboration between the public and private. Public sectors also are strongly encouraged to identify the benefits acquired by development and compliance of the international technical standards. Furthermore, in order to maximize the potential capacity of ICT, improvements of social infrastructures are required by the public sectors together with private businesses. With the realization of the collaboration works, Asian regions are well deserved to take the lead in future ITS initiatives.     

高铁动车组司机连续作业时长的研究

本文在分析动车组司机感知、判断、操作特性的基础上,采用实验心理学测试方法采集司机的各项指标,根据试验测试数据,通过贝叶斯统计学的方法确定合理的高铁动车组司机乘务作业时长,建立乘务作业时长与各项测试指标之间的关系模型。通过算例验证,动车组司机安全可靠度测试等级为良好,并提出相应的改进措施     

Missing the tide? Workplace cultural differences as a barrier to seafarer mobility in the U.S. workboat and sail training sectors

ABSTRACT

While previous research details the psychological and social benefits of sail training programs for amateur ‘trainees,’ much less is known about the value and transferability of sail training work experience in terms of professional development for seafaring careers. This article reviews the current state of scientific knowledge on sail training and presents the findings of a qualitative study of maritime recruiter perceptions at 10 U.S. flag workboat companies. Results suggest that the maritime industry may benefit from an improved understanding of the role that sail training programs and the sail training community can play in training and inspiring the next generation of motivated and professional seafarers. Workboat recruiters see positive and negative aspects of sail training experience and perceive cultural divides within the maritime industry that may affect a seafarers’ job mobility, whether or not such divides actually exist.     

The Dutch mobility panel: Experiences and evaluation

The aim of this paper is to give an overview of the history and research experiences of the Dutch National Mobility Panel. Attention is given to the sampling strategy, the policy goals, and the representativity of the panel. It also tries to evaluate the research outcomes in terms of the original objectives and in view of more general research and policy goals. In sections one and two, a historic overview is given, starting from the first ideas to implement a longitudinal research instrument in transportation planning. In section three, some attention is devoted to longitudinal versus cross-sectional analyses. In section four, the sample design is treated in some detail. Next, various forms of bias are discussed that affect the representativity of the panel. In the sixth section, an overview is given of the research conducted with the data. Some conclusions are given in the final section.     

Rural mobility and mode choice: Evidence from the 2001 National Household Travel Survey

This article uses data from the 2001 National Household Travel Survey (NHTS) to compare travel behavior in rural and urban areas of the U.S. As expected, the car is the overwhelmingly dominant mode of travel. Over 97% of rural households own at least one car vs. 92% of urban households; 91% of trips are made by car in rural areas vs. 86% in urban areas. Regardless of age, income, and race, almost everyone in rural areas relies on the private car for most travel needs. Mobility levels in rural areas are generally higher than in urban areas. That results from the more dispersed residences and activity sites in rural areas, which increase trip distances and force reliance on the car. Somewhat surprisingly, the rural elderly and poor are considerably more mobile than their urban counterparts, and their mobility deficit compared to the rural population average is strikingly less than for the urban elderly and poor compared to the urban average. Data limitations prevented a measurement of accessibility, however, and it seems likely that rural areas, by their very nature, are less accessible than urban areas, especially for the small percentage of car-less poor and elderly households.     

独立旋转车轮及其在低地板城轨车辆上的应用

文章阐述了独立旋转车轮的发展及其现状,对其导向机理进行了分析,并以近年来国外最新开发的低地板城轨车辆为例,介绍了独立旋转车轮在现代低地板城轨车辆上的应用,通过与采用传统轮对转向架实现低地板化设计的城轨车辆对比,论述了低地板城轨车辆的发展趋势,并对低地板城轨车辆在我国的运用前景进行了展望。     

线激励下船舶混合构型加筋板的振动特性

文章对某船发电机舱纵向混合构型加筋板的导纳特性进行了研究,运用模态叠加法求解了结构在线激励作用下各特征线上的等效导纳。计算结果显示,根据振动能量在结构上的分布,可按频段将导纳特性分为输入主控区和传递主控区。输入主控区导纳呈现带通特性,三个通频带与相应的筋条结构对应。通过改变筋条的参数可以单独控制加筋板某个频段的导纳特性。