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991.
以ansys为计算平台,建立了列车—轨道—基础—结构的三维动力相互作用分析模型,分析了列车运行引起的环境振动问题及对周围结构的影响,结果表明:在软土情况下,列车引起的建筑物的竖向振动比较大;建筑物的振动也基本随车速的增大而在增大;轴重大的货车引起的振动响应比客车要大;改变建筑物的自身结构刚度特性对水平向加速度的改变较明... 相似文献
992.
AMBER H. HIMES 《Coastal management》2013,41(4):389-408
Marine resource management and related stakeholder conflicts have been clearly defined in recent decades as pressing issues worldwide. This article provides a comparative study of the management regimes of the Gulf of Castellammare Fishery Reserve and the Egadi Islands Marine Reserve in Sicily, Italy. What managers in these two reserves have neglected to include in management is a social science evaluation scheme to ensure the development of more effective overall management. This is a significant problem in both Italy and the rest of the Mediterranean, where few sociocultural and economic studies have been conducted. Using data collected with standard anthropological field methods, analysis was conducted on how artisanal fishers are impacted by reserves, the extent of their knowledge regarding regulations, their opinions on management, and demographics. The results indicate that while fishers in the two case studies are all aware of the marine reserves where they fish, most fishers are not well informed of the associated regulations. Fishers feel alienated from the management process, and would feel more comfortable with reserve managers and regulations if they were involved in management. The article concludes by showing how such data could help to develop more useful and practical management practices in both these and other MPAs with similar problems. 相似文献
993.
Sixty percent of the Philippine's population resides in the coastal zone. Women and men in coastal communities depend chiefly on the sea for subsistence. Over fifty percent of the dietary protein requirements of coastal communities are derived from municipal fisheries and shallow coastal habitats (reef fishes, marine plants, and mangroves). Coastal populations are young and expanding at rates that exceed regional and national averages. Expanding human pressures and man-made disturbances (over harvesting, destructive fishing, siltation, etc.) that offset natural processes are destroying habitats and creating protein food security crises and increasing malnutrition. At the same time conflicts among users of coastal resources are escalating. Access constraints, gender inequities, and cultural barriers stymie options for women and men to plan their families and create alternative livelihoods. National and local government agencies are addressing food security concerns through vertical policies and programs (e.g., fisheries management, integrated coastal management). The IPOPCORM project uses a cross-sectoral approach and quasi-experimental evaluation design to test the hypothesis that food security will be achieved more quickly when coastal resources management (CRM) and reproductive health (RH) management are implemented together. The purpose of this article is to review the project's experience and highlight the trends observed in program monitoring and evaluation during 2001–2004, which suggest better impact on RH, CRM, and gender indicators in the sites where the synergistic approach is being applied. 相似文献
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ABSTRACTRisk assessment in maritime domain is one of the most cited topics since maritime transportation poses potential hazard for human life, marine environment and property. To mitigate risk and enhance safety awareness in maritime transportation, safety researchers have been seeking proactive solutions. This article prompts a quantitative risk-based approach combining interval type-2 fuzzy sets (IT2FSs) with failure mode and effect analysis (FMEA) to perform a comprehensive risk analysis. Thus, potential failure modes and their effects are revealed by calculating risk prioritisation numbers (RPNs). Whilst the FMEA method provides a robust risk analysing tool with relevant control options, the IT2FSs deals with ambiguity and vagueness of linguistic assessment of decision-makers through the FMEA. Hence, expert’s linguistic assessment in risk assessment can be transformed into useful information in terms of enhancing safety and pollution prevention in maritime industry. To demonstrate the proposed approach, potential failures and effects of a real shipboard oil spill case are handled. The findings show that incomplete information exchanged with local maritime authorities, malfunction of oil skimmer and poor organization of shoreline clean-up team are the most important failures during case of oil spill. The proposed approach provides not only theoretical insight into the maritime transportation industry but also practical contributions to chemical/oil tanker safety and environmental protection by mitigating risk in terms of technical or operational aspects. 相似文献
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以浙江省各气象观测站风场数据为基础,根据信息扩散理论分析了浙江省及其沿海地区最大风速、大风天数的风险概率及其空间分布.研究表明:浙江内陆大部分区域10a一遇最大风速为15~20m/s,中部沿海为30~40m/s;7~9月是沿海大风发生风险概率较高的月份,嵊泗站冬夏季节9级以上大风概率较低,春秋季节风险概率较高;7级以上大风6d/月和12d/月的风险概率有比较明显的季节性;嵊泗站在春季、大陈岛站在10月至次年3月相比其他月份风险概率较高. 相似文献
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在对张承高速公路施工现场生态环境现状进行调研的基础上,提出了项目区的生态环境等级。阐明了土壤类型,适宜生长的植物;对水土流失现状进行了分析、评价,提出了水土流失防治标准;评定出项目所在地的各项生态环境指标均处于三级水平,已达危险边缘,必须采取强有力的治理措施,在高速公路建设过程中,尽快恢复较好的生态环境。 相似文献