A Method for Evaluating Marine Protected Area Management

An assumption underlying the growing support for marine protected areas (MPAs) is that they meet conservation goals and provide economic benefits to fisheries and ecotourism. However, support for MPAs will be at risk if managers cannot assess whether various MPA objectives are being fulfilled. Current approaches to MPA management emphasize the need to evaluate performance criteria; however, there is little consensus on criteria and their evaluation. We propose a marine protected area evaluation model (MPAEM), based on and modified from a multidisciplinary approach used to assess the sustainability of fisheries, called rapid appraisal of fisheries (Rapfish). The application of the MPAEM was explored in a pilot study of 20 MPAs located in different regions of the world. Results indicate that the MPAEM can be used to evaluate MPA management effectiveness. However, the manner in which the evaluation attributes are scored and ways of engaging user groups should be explored before MPAEM can become part of the day-to-day management of MPAs.     

考虑应变率效应的船体板格冲击动力响应与结构强度准则研究

针对承受冲击载荷的船体板格,提出一种考虑材料动态特性的失效评估准则,并采用LS-DYNA对其合理性进行了验证。此方法考虑了材料的应变率效应对其屈服强度特性的影响以及冲击时间临界值对船体板格最大永久变形的影响,反映了结构动态失效行为特征,具有一定的工程意义和参考价值。     

公路卧铺客车平顺性随机输入行驶试验研究

讨论了公路卧铺客车平顺性随机输入行驶试验方法和评价标准，并通过试验来分析试验方法和评价标准，认为卧铺客车平顺性随机输入行驶试验方法与普通客车相比主要应注意正确建立坐标系，且认为ISO2631评价标准暂时不能用于严格评价卧铺客车的平顺性。     

Life cycle ownership cost and environmental externality of alternative fuel options for transit buses

This paper assesses alternative fuel options for transit buses. We consider the following options for a 40-foot and a 60-foot transit bus: a conventional bus powered by either diesel or a biodiesel blend (B20 or B100), a diesel hybrid-electric bus, a sparking-ignition bus powered by Compressed Natural Gas (CNG) or Liquefied Natural Gas (LNG), and a battery electric bus (BEB) (rapid or slow charging). We estimate life cycle ownership costs (for buses and infrastructure) and environmental externalities caused by greenhouse gases (GHGs) and criteria air pollutants (CAPs) emitted from the life cycle of bus operations. We find that all alternative fuel options lead to higher life cycle ownership and external costs than conventional diesel. When external funding is available to pay for 80% of vehicle purchase expenditures (which is usually the case for U.S. transit agencies), BEBs yield large reductions (17–23%) in terms of ownership and external costs compared to diesel. Furthermore, BEBs’ advantages are robust to changes in operation and economic assumptions when external funding is available. BEBs are able to reduce CAP emissions significantly in Pittsburgh’s hotspot areas, where existing bus fleets contribute to 1% of particulate matter emissions from mobile sources. We recognize that there are still practical barriers for BEBs, e.g. range limits, land to build the charging infrastructure, and coordination with utilities. However, favorable trends such as better battery performance and economics, cleaner electricity grid, improved technology maturity, and accumulated operation experience may favor use of BEBs where feasible.     

模糊综合评判应用于工程机械评定的研究

本文把模糊综合评判应用于工程机械的产品评定.介绍了以推土机为例的工程机械产品的综合评价方法.     

新旧公路隧道围岩分级方法的比较

随着我国经济建设的发展,公路隧道,尤其是高速公路隧道和一、二级公路隧道的建设越来越普遍,并且呈现数量多、埋藏深、长度大的特点。因此,对隧道进行超前地质预报和围岩分级也就显得越来越重要,目前我国交通部编写的规范中详细介绍围岩分级的主要有《JTJ 064-98公路工程地质勘察规范》和《JTG D70-2004公路隧道设计规范》。以沪蓉西高速公路扁担垭隧道为例,对新旧两种公路隧道围岩分级规范进行了比较,分析了新旧规范在此隧道中的适用性,探讨了其各自的特点、不足和今后围岩分级的发展方向。     

船舶稳性衡准研究的发展综述

文章在回顾船舶稳性发展的基础上,对现阶段完整稳性、随浪稳性、倾覆现象、破舱稳性的研究进展做了进一步阐述,最后对今后船舶稳性研究工作提出了建议。