复合材料碳纤维布加固含裂纹钢梁实验研究

采用15根模型钢梁的试验研究,结果表明:利用不同长度,不同厚度补片加固后的梁静强度的变化是不一样的;全长补片短补片长度加固效果好,随补片厚度的增加其静强度也有所增加,与未加固对比梁相比较最大静承载力提高55%;梁加固前后的刚度变化不太明显;加固后梁的延性有所降低.     

狮子洋隧道过小虎沥水道施工技术

文章以广深港铁路客运专线狮子洋隧道盾构法穿越小虎沥水道工程为例,重点介绍了过江施工过程中的风险点及重难点,并提出了盾构刀具配置、开挖面泥水压力控制及处理系统管理、背后注浆、盾尾漏浆防治等针对性技术及措施。     

Digging Deep: Managing Social and Policy Dimensions of Geoduck Aquaculture Conflict in Puget Sound,Washington

Shellfish aquaculture can result in conflicts among stakeholders who perceive impacts and tradeoffs regarding sense of place, aesthetic, recreational, economic, and ecological values. Pacific geoduck clams (Panopea generosa Gould 1850) are grown in intertidal plots using gear- and labor-intensive techniques that result in a high value export product. A confluence of issues has resulted in on-going social and legal tensions surrounding geoduck aquaculture in southern Puget Sound, Washington (WA), USA. Using interviews and document analysis, we explored stakeholder perspectives and policy issues related to geoduck aquaculture in southern Puget Sound. Twenty-three stakeholders were interviewed, including state agency employees, representatives of the aquaculture industry, nongovernmental organizations, landowners, a tribal member, and an academic. Nine state hearings board decisions on challenges to aquaculture permits were also analyzed. Stakeholders articulated a variety of perspectives regarding aesthetic, recreational, land-use, ecological, political, regulatory, and economic aspects of geoduck aquaculture activities. Hearings board cases addressed similar issues (aesthetic, ecological, and recreational), as well as challenges to restrictions on aquaculture. Potential strategies for managing this conflict include emphasizing best management practices, identifying and incorporating best available science, joint fact-finding approaches, and initiating and improving communication among all stakeholders.     

Structural equation modeling of user satisfaction of bus transit service quality based on stated preferences and latent variables

Few studies have been conducted on the service quality (SQ) of bus transit in developing countries. This paper presents a structural equation modeling (SEM) approach to identifying the relationships among major attributes that affect the SQ of bus transit in the city of Dhaka in Bangladesh. Specifically, 22 bus transit SQ attributes, drawn from 655 questionnaires, are used to develop different SEM models for the city. Along with stated preferences, the effect of three latent variables on SQ is analyzed. Among the developed models, the best model is selected by using different statistical approaches. With the best model, selected attributes are rated according to their relative importance on SQ. Acknowledging limited resources of a developing nation, this study gives a clear way ahead to planners, operating companies and transport managers to design appropriate transport policies which will ensure more effective services to current bus users as well as attracting new passengers.     

增强海员健康意识 保证海上航行安全

在研究WHO的健康的定义和STCW 95公约对于海员健康要求的基础上,提出了增强海员健康意识,提高海员身体素质是保证海上航行和人命财产安全的重要条件之一。     

谈农村公路工程造价的控制

农村公路项目工程造价控制工作贯穿于项目建设的全过程,在这期间,着重立项、设计阶段,不忽视招投标与施工结算阶段,加强项目完结后的评价工作,这是行之有效的方法。     

依靠科技创新全面提升交通运输发展水平——交通运输部高宏峰副部长在西部大开发交通科技工作交流会上的讲话

文章总结了十年来西部交通科技工作所取得的成果与经验,分析了西部交通发展面临的瓶颈问题,提出了依靠科技创新来全面提升西部地区乃至全国的交通运输现代化建设水平的发展思路。     

Modelling with joint choice of ports and countries of origin and destination: application to Colombian ports

Literature has focused on studying port choice independently or as an element of a supply chain without considering the joint selection with the country of origin/destination of the imports/exports. However, the characteristics and location of a port may make it more attractive to mobilise more freight from/to some particular countries rather than others, making the port choice decision dependent on the country of origin/destination of the cargo. This article proposes advanced econometric models to evaluate simultaneously port choice and the country of origin/destination choice for Colombian imports and exports. Findings suggest that for imports and exports domestic freight rate is the most important variable for the joint choice process. Also, for exports, maritime transit time is more relevant than for imports, while for the frequency of shipping lines the opposite is true. The existence of a trade agreement and the gross domestic product per capita also have a significant influence on the election of a country for exports/imports.     

桥梁承载力不足的成因及加固方法探讨

文中从广东省桥梁现状入手,分析了造成桥梁承载力不足的原因,探讨了桥梁加固的一些方法及在实际施工中的应用,提供了桥梁加固方面的一些做法和经验。     

基于云模型和蒙特卡洛方法的通航环境系统风险评价

在通航环境系统风险评价的实践过程中,往往面临很多不确定性因素,这使得风险评价工 作的开展面临一定的困难。为充分利用不确定性信息并克服其不利影响,将云模型和蒙特卡洛方 法引入船舶通航环境系统风险评价,构建了基于正态云模型和蒙特卡洛思想的通航环境系统风险 综合评价模型,并给出了实现方案。模型中,以正态云模型为工具实现风险评价过程中定性描述 和定量表示之间的相互转换,实现了基于云模型的通航环境系统各因素的风险评价;采用蒙特卡 洛方法得到通航环境系统风险云模型的三个关键参数。以杭州湾跨海大桥通航环境风险综合评价 为例,对所建模型的可行性和有效性进行了验证。研究表明,该模型能够作为在不确定性环境下 实现通航环境系统风险综合评价的一种有效方法。