基于X射线技术的安全检查设备在地铁安检中的应用

地铁X射线安全检查设备能够分辨出有机物、无机物和混合物（或轻金属）,能有效阻止违禁品和限带品被带入地铁站内,是保障地铁安全的重要手段。介绍了X射线安全检查设备的特点、原理、结构组成和功能。     

Benthic megafauna communities under the influence of the South Atlantic Central Water intrusion onto the Brazilian SE shelf: A comparison between an upwelling and a non-upwelling ecosystem

The structure and dynamics of the benthic invertebrate megafauna of the Southeastern Brazilian shelf were studied over a 2-year period. Two regions presenting different oceanographic conditions, Ubatuba-SP and Cabo Frio-RJ were compared in terms of biomass, density of organisms and species richness. Two to three 30-min tows were undertaken at each of the stations, located at 40 and 100 m isobath, in a normal transect offshore of both regions. Faunal distributional patterns correlated with water mass dynamics, depth and sediment parameters. In the Cabo Frio region, subjected to a Ekman-driven seasonal coastal upwelling, the impact of the South Atlantic Central Water (SACW) on the inner shelf leads to a change in the benthic communities, with a high dominance of top carnivores such as the crab Portunus spinicarpus and the sea-star Astropecten brasiliensis, which accounted for the larger part of the total biomass. Distinct species associations were found in each of the two regions and the total biomass at Cabo Frio inner shelf was almost twice that of Ubatuba during the 2002 summer, when a marked upwelling was verified. The relationship between megabenthic biomass and input of organic matter to the sea floor during upwelling events is discussed.     

高速公路交通流建模综述

交通流建模是智能交通自动控制、分析、设计、仿真和决策的前提, 历来是交通工程界的一个重要的研究课题, 分三条主线(宏观交通流模型、微观交通流模型、其它交通流模型) 对交通流建模的发展做了详细介绍, 并在文末提出了对交通流建模今后发展的展望     

公路养护机械设备维修和维护管理策略

随着建筑事业的不断发展,在公路工程施工中对机械设备进行科学合理的维修和养护也逐渐受到重视。对公路养护机械设备维修和维护管理策略进行探讨,从公路养护机械设备出现故障的主要原因入手,分析机械设备的内部问题和外部因素对机械设备的影响,对机械设备维修管理的问题进行分析,提出对公路养护机械设备进行维修和维护的相关管理策略。研究认为,要实现对公路养护机械设备的合理维修和维护,必须使机械设备自身的特点与工程施工相结合,才能找到最合理的维修和维护方法。     

Sustainability perspectives when crop use is implemented in different sectors: A life cycle assessment approach

The present study aims to provide a preliminary overview of the sustainability concept when biomasses conceived for food goals become the raw materials upon which different sectors, such as plastic or energy industry, can develop innovative strategies, according to a so called ??greener?? competitiveness. In the results hereafter presented, the definition of sustainability perspectives, according to the use of a life cycle assessment (LCA) approach, will be described for maize use as raw material in different sectors. The current biopolymer industry and conventional biofuel technologies, the so called first-generation biofuels, are the more and more in competition with the food sector. The presented environmental evaluation, in terms of air emissions, energy and water consumption, is useful in order to understand the sustainability of a bio-sourced product, in comparison with the equivalent item produced by fossil fuels.     

Railway Vehicles with Perfect Curving Behaviour Which are Asymptotically Stable at Vanishing Speed

Paper deals with the linear behaviour of a railway vehicle with any arbitrary number of wheelsets, body parts and connecting elements. A vehicle which has both perfect curving properties and asymptotical stability at vanishing speed, has to satisfy a twofold condition, indicated by Wickens in 1978. In the present paper this condition is derived in reliance upon the dimension theorem for linear mappings. How the investigation can be executed in practice, is shown for the case of a two-axled vehicle. At last the behaviour in a transition curve is discussed.     

When are subsidies to trans-European network projects justified?

The trans-European transport network (TEN-T) encompasses the major planned transport infrastructure in Europe, ranging from high speed rail to port infrastructure. Projects in this category are considered priority projects and receive European subsidies; but these have been insufficient to get these projects off the ground. This paper addresses two research questions. First, it sketches the basic economics of cross-boundary infrastructure projects: what pricing and investment policies can we expect, what is the role of through traffic and high fixed costs of infrastructure? Second, it examines briefly what lessons the EU could draw from the experience of other existing federal funding institutions like the US and Germany. These ideas are used to propose a new subsidy scheme for the TEN-T projects.     

尘肺X线胸片的计算机辅助诊断

用模拟和数字两种方法增强图象，以突出病灶，然后运用新颖的区域生长法识别、测量单个尘肺小阴影，通过统计运算进行尘肺病的诊断和分期。此种辅助诊断方法，提供信息直观可靠。３０例Ｘ线胸片密集度测定结果，与矽肺病期级别相一致。     

基于AQWA的旁靠油轮水动力相互作用研究

船舶旁靠系统的水动力响应是一个非常复杂的工程问题,系统中每一个结构的动力响应会受到其他结构的耦合影响。针对两旁靠FPSO和LNG运输船组成的旁靠系泊系统,基于三维势流理论,应用多体水动力学软件AQWA,在考虑两船间水动力相互作用的情况下,计算两旁靠船舶所受到的波浪载荷,并与不考虑两船水动力相互作用的计算结果进行对比分析。结果表明,旁靠系泊系统水动力相互作用是不可忽略的。同时也分析了不同旁靠间距对水动力性能的影响,结果发现旁靠间距只在中高频段时对水动力性能的影响较大。研究结果可为旁靠系统系泊方案的设计和研究提供一定的参考。     

有轨电车和轻轨车辆的防碰撞性

为提高有轨电车和轻轨车辆的防碰撞性,研制了防碰撞的车体结构,并进行了试验验证。