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201.
Sarah Christie 《Coastal management》2013,41(3):245-257
As noted often by the former California Coastal Commission Executive Director Peter Douglas, the history of how the California coast was saved is a great repository of untold stories. Although the Commission has had a dramatic and tangible impact on California's coastal geography, the public is largely unaware of many of its early accomplishments. This article begins to chronicle the rich stories of California's coastal legacy by telling the story of how the Commission utilized the Coastal Zone Management Act (CZMA) to prevent Southern Pacific Railroad from developing a seven-mile stretch of the Monterey Bay shoreline. In so doing, the Commission helped make possible the creation of the Monterey Peninsula Recreational Trail, a public bicycle and pedestrian path that has grown to sixteen miles in length and runs through the heart of John Steinbeck's world-famous Cannery Row. The controversy also was the subject of the first judicial challenge of a state's federal authority under the CZMA and precluded private commercial and residential development that would have dramatically altered the urban form of the Monterey Peninsula. It is important to tell the story as the Coastal Commission's role in this remarkable accomplishment has been almost completely overlooked. 相似文献
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203.
Understanding public perception of the oceans, and relationship between society and the sea is an important key to the sustainable management of marine resources. This research reports the first population-based survey on Taiwanese public knowledge, attitudes, and actions on marine-related issues. The stratified random sampling by county was completed with 1,120 telephone respondents from October to December 2010. More than 60% of the respondents have heard about global warming, sea-level rising, the Gulf of Mexico oil spill, the coral reef bleaching crisis, and Japan whaling fisheries. However, less than 20% of the respondents are aware of Taiwanese domestic marine policies, such as the Ocean White Paper. On resources conservation, 74.7% of the respondents support the bluefin tuna catches regulations and 76.6% agree that the shark fin fisheries will impact shark resources. Education and age are the major affecting variables for resource conservation and knowledge. Higher education and age 40–49 are most supportive of conservation measures. For marine recreational activities, 42.2% of the respondents can swim, and 44.2% of the respondents had not visited the beach in the previous year. The results suggest that the government could establish a specialized agency to strengthen its marine policy and take more actions to protect ocean environment and conserve marine resources. To encourage more Taiwanese to participate in ocean recreational activities, the government could build a safe facility for marine recreation, cooperate with the private sectors in education, and provide outreach to raise public awareness of the oceans. 相似文献
204.
Willett Kempton Jeremy Firestone Jonathan Lilley Tracy Rouleau Phillip Whitaker 《Coastal management》2013,41(2):119-149
Wind power resources on the eastern U.S. continental shelf are estimated to be over 400 GW, several times the electricity used by U.S. eastern coastal states. The first U.S. developer proposes to build 130 large (40 story tall) wind turbines in Nantucket Sound, just outside Massachusetts state waters. These would provide 420 MW at market prices, enough electricity for most of Cape Cod. The project is opposed by a vigorous and well-financed coalition. Polling shows local public opinion on the project almost equally divided. This article draws on semistructured interviews with residents of Cape Cod to analyze values, beliefs, and logic of supporters and opponents. For example, one value found to lead to opposition is that the ocean is a special place that should be kept natural and free of human intrusion. One line of argument found to lead to support is: The war in Iraq is problematic, this war is “really” over petroleum, Cape Cod generates electricity from oil, therefore, the wind project would improve U.S. security. Based on analysis of the values and reasoning behind our interview data, we identify four issues that are relevant but not currently part of the debate. 相似文献
205.
管涵周围土压力的分布规律对管涵结构的设计具有重要的参考价值,然而采用传统M-S理论计算管涵顶部垂直土压力存在一定的局限性。针对这一问题,以沟埋式管涵为研究对象,首先运用理论分析的方法对土体在沟槽摩擦作用下形成的小主应力拱展开了研究,并据此对矩形沟槽管涵的侧压力系数和顶部垂直土压力计算公式加以推导。然后以具体工程为例,对公式的合理性进行了探讨和分析,并对管涵的设计提出了一些合理性建议。 相似文献
206.
王喜宏 《内蒙古公路与运输》2010,(5):61-62
农村汽车客运站是农村道路运输的重要公益性基础设施,是整个道路运输市场体系的重要组成部分。农村汽车客运站的建设对改善农民群众出行条件、提升乡镇公共服务水平、推动农村经济发展、服务“三农”、建设社会主义新农村具有重要意义。文章针对当前农村汽车客运站建设及运营管理存在的问题,提出整改思路。 相似文献
207.
208.
《铁道标准设计通讯》2016,(6):71-75
目前运营时速160 km以下(双箱运输)有砟轨道隧道内轮廓难以满足大型养护机械(特别是大型清筛机)作业空间需求,通过对新建时速160 km以下电气化铁路(双箱运输)有砟轨道隧道的建筑限界、接触网悬挂方式及布置、大型养护机械空间需求、轨道结构形式、侧沟及电缆槽设置等内轮廓影响因素进行综合分析,确定单双线铁路有砟轨道隧道内轮廓控制性尺寸、拟定内轮廓方案,通过对各型内轮廓方案的结构安全性、经济性及施工便利性比较,给出推荐方案,为通用图编制和纳入规范奠定基础。 相似文献
209.
《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):849-866
One of the most important maintenance costs in tramway transport comes from wear of wheel profiles. In the highly competitive railway market, the prediction of wear is then a major concern of the constructors. In this article, we present and compare four models well adapted to tramway conditions, involving contacts on the rolling tread and on the flange with very different sliding and pressure conditions. Moreover, all models can be implemented from the natural outputs of the railway simulation packages classically used in industry for the dynamics design of the vehicles. The first one, proposed by Jendel, is based on the well-known Archard's wear model. Enblom continues Jendel's approach by taking into account the contribution of wheel deformation on the sliding velocity. The last two models, developed by Zobory, and Pearce and Sherratt, determine the wear from the energy dissipation in the contact area. The models are first compared on a theoretical basis and, for that purpose, are rewritten in a common form. Two cases are distinguished: mild wear as arising on the rolling tread and severe wear as arising on the flange. The models are also compared in the practical case of an urban transport vehicle running on circular tracks with different curve radii. Although the models show equivalent trends according to the theoretical study, important discrepancies appear between estimated wear depths. All models are actually dependent on experimental coefficients and it is likely that they were estimated in different conditions. On the other hand, a reasonable agreement can be found in some particular conditions. As an example, Zobory's, Enblom's and Jendel's models are very close to each other in severe wear conditions. This work shows that a general and reliable model could probably be developed from all positive aspects of the existing ones. 相似文献
210.
轨道交通综合枢纽规划探讨 总被引:2,自引:1,他引:1
结合上海、昆明、深圳等城市的轨道交通综合枢纽工程,对总平面布置、各种交通方式的衔接及客流组织等内容进行了探讨,特别对城市轨道交通车站与铁路站房的衔接进行了讨论,并对福田轨道交通枢纽设计案例进行了分析。 相似文献