南京市快速公交系统（BRT）的规划和建设

南京积极推进公交优先发展战略的实施,优化交通结构,提高公交对市民出行的吸引力。本文介绍了BRT的组成与基本元素,从中国城市的实际出发,阐述了“优先发展公共交通”、“绿色交通”的理念,提出了公交体系建设的基本要求,介绍了BRT在省内城市常州、连云港的应用,针对南京快速公交现状与需求,提出BRT建设和管理的建议。     

有限水深三维脉动源格林函数数值算法研究

由于柯西主值积分的奇异性和贝塞尔函数的振荡性,有限水深情况下复杂格林函数及其导数的精确数值求解一直是浅水中波浪水动力计算的难点,因此寻找格林函数的精确数值解显得非常重要.通过对格林函数奇异项进行变形推导,文中给出了一种去掉了奇点的新积分形式.另外通过改进前人推导的Gauss-Laguerre积分方法,给出了一种改进的新Gauss-Laguerre积分方法.格林函数及其导数的数值结果显示文中给出的两种新方法可以有效地计算复杂格林函数及其导数值.最后对这两种方法、级数解以及传统的Gauss-Laguerre积分方法的计算精度和效率进行了比较研究,结果显示文中给出的两种方法的计算精度高于传统的Gauss-Laguerre积分方法,但其计算效率低于级数解.但在接近于0的近场附近级数解失真,而文中提出的改进的新Gauss-Laguerre积分方法可以获得正确结果.同时当频率和水深均较大时级数解失真,而文中提出的方法也可以获得正确结果.最后针对这些方法的优缺点,该文提出了建议的策略用于计算有限水深格林函数.     

基于电弧放电的电极加热方法处理焊渣

基于气体弧光放电原理的电极加热技术,已经在焊接、切割、熔炼金属工艺[1,2]上得到了很好的应用,文中以创新性弧光放电技术来完成船厂中的焊渣清理工作。目前,基本上大部分船厂都是利用人力手工操作打磨机打磨掉焊接中飞溅的焊渣,这与当今世界倡导的绿色造船理念背道而驰,故船厂焊渣清理工作的机械化、效率化、流水线化已十分迫切,本文从原理的角度阐述利用弧光放电解决该问题的可行性。     

绿色通道鲜活车辆逃费的类别及应对措施

文章介绍了绿色通道逃费车辆的逃费类别,阐述了整治绿色通道鲜活车辆逃费存在的困难,并提出了防治假冒鲜活车辆偷逃通行费的措施。     

Required test durations for converged short-term wave and impact extreme value statistics — Part 1: Ferry dataset

For the design of maritime structures in waves, the extreme values of responses such as motions and wave impact loads are required. Waves and wave-induced responses are stochastic, so such responses should always be related to a probability. This information is not easy to obtain for strongly non-linear responses such as wave impact forces. Usually class rules or direct assessment via experiments or numerical simulations are applied to obtain extreme values for design. This brings up questions related to the convergence of extreme values: how long do we need to test in order to obtain converged statistics for the target duration? Or, vice versa: given testing data, what is the uncertainty of the associated statistics? Often the test or simulation duration is cut up in ‘seeds’ or ‘realisations’, with an exposure duration of one or three hours based on the typical duration of a steady environmental condition at sea, or the time that a ship sails a single course. The required number of seeds for converged results depends on the type of structure and response, the exposure duration, and the desired probability level. The present study provides guidelines for the convergence of most probable maximum (MPM) wave crest heights and MPM green water wave impact forces on a ferry. Long duration experiments were done to gain insight into the required number of seeds, and the effect of fitting. The present paper presents part 1 of this study; part 2 [1] presents similar results for wave-in-deck loads on a stationary deck box.