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71.
72.
山西平遥至榆社高速公路穿越自然保护区路段的生态环境影响评价 总被引:2,自引:2,他引:2
结合山西平遥至榆社高速公路的环境影响评价工作,通过对拟穿越超山自然保护区路段生态环境现状的调查,论述了公路建设可能对生态环境造成的影响,并提出了相应的措施和建议。 相似文献
73.
为了实现恶劣条件下对扭矩的精确稳定测量,设计并实现了一种新型的基于光纤光栅的扭矩传感器。为克服扭矩测量系统易受外界影响的缺点,设计了光纤光栅全桥光路,实现了温度和弯矩的自动补偿。通过扭矩标准装置加载试验和水下环境加载试验分别测试了其测量精确度以及水下工作性能。结果表明,该光纤光栅扭矩传感器的最大非线性误差、重复性以及水下工作稳定性均达到0.1%以内,说明该传感器不但具有良好的测量精度,而且能够在船用环境等恶劣扭矩测量条件下较好地工作。研究结果为船用环境中扭矩测量的研究与应用提供了重要参考。 相似文献
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75.
Iris Hui 《Coastal management》2017,45(3):179-198
This paper examines the California Coastal Commission's permitting process. Using several text mining techniques, including web scraping, information extraction, and supervised classification, I demonstrate how to retrieve empirical data from unstructured texts, namely public meeting agendas and staff reports. Contrary to the concern that the Commission routinely delays or rejects permitting requests, the data reveal that outright rejection of permit applications is rare. On average, eight of ten applications were approved. Single-family homes and commercial development projects were approved about 80% of the time; the rates were about 70% for seawalls and retaining walls, and 60% for land-use changes. Most applications were processed swiftly, with a median application length of 3 months. The agency's influence comes primarily from negotiating each application. Qualitative study of 50 cases pertaining to single-family home construction reveals that the agency adopts a “managed development” approach, that is, allowing development but scrupulously managing various aspects of development. These case studies illustrate how the agency interprets the broad, abstract state laws and translates the mandates into enforceable actions as permitting conditions. In areas where the state mandates conflict, particularly over development in receding shorelines, the agency has the largest leverage in creating and implementing its preferred policies. The text mining techniques demonstrated in this paper can be applied to study any governmental agency. These techniques help to extract information from a massive volume of papers and organize them into a database for analyses. The empirical data extracted from texts can significantly increase bureaucratic transparency. 相似文献
76.
Zhibin Li Wei WangPan Liu David R. Ragland 《Transportation Research Part D: Transport and Environment》2012,17(3):256-261
This study investigates the impacts of physical environments on bicyclists’ perceptions of comfort on separated and on-street bicycle facilities. Based on a field investigation conducted in Nanjing, China, we find that physical environmental factors significantly influencing bicyclists’ perception of comfort on the two types of facility. Cyclists’ comfort is mainly influenced by the road geometry and surrounding conditions on physically separated paths while they pay attention to the effective riding space and traffic situations on on-street bicycle lanes. 相似文献
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为解决复杂环境下基坑开挖时下方地铁隧道正常运营的难题,依托郑州某市政管廊上跨地铁区间隧道项目,采用三维数值模拟计算及施工监测数据分析的方法。得出如下结论: 1)通过选取合理的基坑围护方案,可减小基坑围护结构施工对地铁区间隧道的扰动影响; 2)对于工程地质情况较好的地区通过细化上跨基坑开挖方式,采用基底加固+抽条施工的方案可保证地铁区间隧道的正常运营。 相似文献
79.
Kelly J. Clifton Carolina V. Burnier Gulsah Akar 《Transportation Research Part D: Transport and Environment》2009,14(6):425-436
This paper examines the impact of personal and environmental characteristics on severity of injuries sustained in pedestrian–vehicle crashes using a generalized ordered probit model. The data covers 2000–2004 of pedestrian–vehicle crashes taken from police incident reports for Baltimore City and supplemented with local land use, urban form and transportation information specific to the individual crash locations. The results on personal and behavioral variables confirm previous findings. Women pedestrians involved in crashes tend to be injured less frequently than their male counterparts; children have an increased likelihood of sustaining injuries and older persons are more likely to be fatally injured. Pedestrians who cross against the traffic signal, are not in a crosswalk and are involved in a crash after dark are associated with greater injury risk. Of the built environment policy variables of interest, transit access and greater pedestrian connectivity, such as central city areas, are significant and negatively associated with injury severity. These results suggest that the environmental conditions should be given more scrutiny and be an important consideration when evaluating and planning for pedestrian safety. 相似文献
80.
舰载武器海洋环境适应性分析 总被引:9,自引:0,他引:9
海洋环境的特殊性对舰载武器在环境适应性设计及贮存和使用过程中的可靠性提出了更高的要求。文章分析了舰载武器面临的海洋环境及其对武器可靠性的影响,提出了提高舰载武器环境适应性和可靠性的措施。 相似文献