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661.
Abstract

Authority to designate marine sanctuaries was established by Title III of the Marine Protection, Research, and Sanctuaries Act of 1972. One may view this authority as the ocean water counterpart to our National Parks and Seashores. Contained herein is a discussion of the components of the Title and how the National Oceanic and Atmospheric Administration (NOAA) plans to carry out the program. Nominations received to date are briefly discussed.  相似文献   
662.
Australia's coastal environments are exposed to great pressures. Adequate policy and management measures are required to ensure the protection of coastal assets now and for future generational use. However, recent government reports and academic literature have highlighted that improved science uptake into policy is needed to ensure coastal communities are protected from impacts such as climate change. The literature suggests that individuals, coined champions, can play an important role in influencing the use of science by policymakers. However, a paucity of research exists surrounding the role of these individuals. This research explores the role of champions in enabling science uptake into policy in the Australian coastal zone, investigating champion characteristics and strategies used in influencing policymakers. A mixed-methods approach to the research was employed, integrating a paper/online survey of people involved in Australian coastal management and in-depth, semi-structured interviews with champions nominated by their peers from the survey. Fourteen key coastal champion characteristics were identified from the survey. Furthermore, the champion interviews identified strategies for influencing science use by policymakers. From these findings a conceptual model was created. In order to enable coastal champions to be fostered, a six-step process was developed that incorporates the use of the conceptual model.  相似文献   
663.

This paper is concerned with a problem area of increasing interest, namely the traffic characteristics of specific generators located on non‐residential land use. It concentrates on the problem of modelling traffic generation for goods, service and business movements at the manufacturing establishment. Firstly the contributions of earlier researchers are reviewed in the context of factors which have been considered important. Then a further study conducted by the author in Sheffield and in Manchester, England, is described. This study considers more rigorously than hitherto the questions of similarities in trip rates over different manufacturing activities and geographical areas, and of the choice of explanatory variables. Comparison of regressions is used to formalize indications of similarities in trip rates, and analysis of variance for choosing the most satisfactory explanatory variables. The study provides evidence of similarity in trip rates over seven different manufacturing activities and two geographical areas. It also shows distinctions between different non‐work traffic types in the extent of similarities in trip rates over different manufacturing activities and in explanatory variables for traffic generation relationships. Regarding the latter it is concluded that it is not possible to model accurately such traffic movements on the basis of explanatory variables which are normally available. Instead trip rates should be expressed in simple mathematical terms and should be based on large data populations. The study also makes contributions on peak flow factors for the actual design of facilities of manufacturing establishments. These findings and others are discussed in the context of the work of earlier researchers. Finally conclusions are drawn and guidance offered for future work into this problem.  相似文献   
664.

This is the fourth time that Transport Reviews has published a summary of the workshop sessions from the Thredbo Conference. The intention is to disseminate more widely the main findings and conclusions from these sessions at this important international conference. Interested readers are also encouraged to view the full papers presented at the Institute of Transport Studies, University of Sydney website.  相似文献   
665.
The US Corporate Average Fuel Economy (CAFE) regulations are intended to influence automaker vehicle design and pricing choices. CAFE policy has been in effect for the past three decades, and new legislation has raised standards significantly. We present a structural analysis of automaker responses to generic CAFE policies. We depart from prior CAFE analyses by focusing on vehicle design responses in long-run oligopolistic equilibrium, and we view vehicles as differentiated products, taking demand as a general function of price and product attributes. We find that under general cost, demand, and performance functions, single-product profit maximizing firm responses to CAFE standards follow a distinct pattern: firms ignore CAFE when the standard is low, treat CAFE as a vehicle design constraint for moderate standards, and violate CAFE when the standard is high. Further, the point and extent of first violation depends upon the penalty for violation, and the corresponding vehicle design is independent of further standard increases. Thus, increasing CAFE standards will eventually have no further impact on vehicle design if the penalty for violation is also not increased. We implement a case study by incorporating vehicle physics simulation, vehicle manufacturing and technology cost models, and a mixed logit demand model to examine equilibrium powertrain design and price decisions for a fixed vehicle body. Results indicate that equilibrium vehicle design is not bound by current CAFE standards, and vehicle design decisions are directly determined by market competition and consumer preferences. We find that with increased fuel economy standards, a higher violation penalty than the current stagnant penalty is needed to cause firms to increase their design fuel economy at equilibrium. However, the maximum attainable improvement can be modest even if the penalty is doubled. We also find that firms’ design responses are more sensitive to variation in fuel prices than to CAFE standards, within the examined ranges.  相似文献   
666.
中国大多数城市中心区公共停车场的规划建设管理都存在一定的障碍,根源在于对公共停车场的经济属性认识模糊。首先,分析当前公共停车场存在的主要问题及其产生根源,认为经济属性界定不清晰导致政府和市场分工不明确,同时增加政府内部管理的复杂度。提出把公共停车场的经济属性明确界定为以市场供给为主体的准公共物品这一结论,并以公共停车场经济属性为基础,提出在解决停车问题上政府和市场的权责界定。最后,对规划阶段的停车设施分类和功能定位、建设管理和运营阶段公共停车场的市场主导等关键技术问题进行研究并提出建议。  相似文献   
667.
为改善违章停车问题、提高城市管理水平,运用博弈论理论对城市道路违章停车进行分析 与研究。将停车问题涉及的监督部门、执法人员、驾驶人视为互相竞争者,考虑博弈各方的支付函数和效用最大化,建立监管部门与驾驶人、驾驶人与驾驶人之间的混合博弈模型,得出监管部 门执法成本和驾驶员违章成本的纳什均衡值,获得了违章停车行为中各方的最优效用。研究结果表明:在一定的执法成本下,交通执法者会采取相应的执法力度,驾驶人违章停车的概率会降 低。同时,驾驶人违章收益期望值越高,其违章停车的可能性会越大。不同驾驶人违章停车亦存在博弈现象,是否同时选择违章停车取决于共同的违章成本。当违章成本处于一定水平之下时,驾驶员之间的违章行为会发生传播效应。  相似文献   
668.
提出了一种网上教学平台上基于文件内外访问倾向性的视频流调度策略.描述了系统架构、存储策略、调度策略与算法.通过对现有流调度算法的研究,结合视频文件内外访问倾向性,提出了一种新的流调度算法.理论分析和仿真实验表明:该算法可有效提高系统吞吐量和热门影片的命中率,降低系统平均等待时间.  相似文献   
669.
In the past decades, a multilayer transshipment network of bulk shipping has been formed along the Yangtze River so as to support the fast development of Chinese iron and steel industry. Yet with the decrease of iron ore trade in China since 2014, the bulk port system on Yangtze River probably will be subject to change in the future. Under this background, this paper aims to analyze the development potential of Yangtze River bulk ports system with a focus on iron ore transshipment. To realize this objective, we firstly sort out the main transshipment patterns of bulk shipping, and optimize the bulk-shipping network with an optimization model. Several scenarios are then proposed and examined in the model by changing corresponding parameters. Cooperation among ports as one scenario is analyzed by applying core theory in cooperative game. Based on the changes of transshipment plans observed under the various scenarios, we finally ascertain the different development potentials of the system, and provide suggestions to the port operators and local maritime authorities.  相似文献   
670.
Massachusetts, like many coastal states in the US, stands to be impacted from climate-induced sea level rise. As a result, climate-sensitive coastal policy instruments are critical for providing adequate adaptation options, including an option to allow coastal features to migrate inland. But the migration of coastal features is under threat due to extensive private armoring. This essay highlights specific regulatory instruments at the federal and state level dealing with hard armoring using Massachusetts as an example. It argues specific federal and state regulations legitimize and incentivize hard armoring over other coastal land use planning methods. The current level of armoring in Massachusetts is highlighted and implications under current federal and state policy frameworks are explained. Suggestions for coastal states planning for sea level rise are discussed, including the need for state planning to take the lead. Recommendations for changes at the federal level are also highlighted.  相似文献   
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