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781.
林久毅 《电气化铁道》2006,(6):14-15,19
通过对自动真空开关分相装置结构形式、工作原理和功能的分析,针对其导致失去实用性的主要缺点,可采取有效的技术措施加以克服,使该方式的半自动相分段装置达到自动化、实用化目的,为此,提出建议性的改进意见。  相似文献   
782.
This article draws lessons about recent innovations in decision support for coping with challenges in integrated infrastructure planning strategies. After setting up a conceptual framework for the scope of analysis and the use of information in infrastructure planning, the empirical section explores the introduction of early-stage sustainability assessment tools. Data collection draws on experiences gained in the Netherlands with a new tool: ‘Sustainability Check’. We conclude that such instruments have a number of capacities that address the challenges of area-oriented planning: (a) bringing together information about the comprehensive value of alternatives, (b) facilitating the generation of alternatives, (c) addressing institutional fragmentation by learning about referential frames, and (d) adding contextual perspectives to the ‘hard’ outcomes of conventional tools. We also conclude that tools such as Sustainability Check should not be seen as a replacement for conventional decision support tools, but rather as complementary to them.  相似文献   
783.
Climate change adaptation presents a difficult challenge for coastal towns around the world, forcing local governments to plan for sea level rise in a contentious decision-making space. The concept of “adaptation pathways,” a diagnostic and analytical tool to assist in adaptive planning and decision-making, is gaining traction as a way of framing and informing climate adaptation. It provides decisionmakers a way to acknowledge the inter-temporal complexities and uncertainties associated with the novel dynamics of climate change and a mechanism to manage these challenges in the local context. In 2012, the Australian Government funded an 18-month program to provide decisionmakers in the coastal zone an opportunity to test the utility of the adaptation pathways concept for coastal climate adaptation. Using a selection of completed projects as case studies, we performed a document analysis to better understand the learnings from the projects. The main themes surrounded: (1) the utility of the adaptation pathway framework in developing options, (2) decision-making rationale and criteria, and (3) stakeholder participation in pathway development. A project participant survey was developed to further understand these themes. Our analysis reveals that “adaptation pathways” was generally framed narrowly and conservatively to emphasize extant economic, administrative and legal considerations over community, participatory, or exploratory ones. Although some case study projects were able to reach a point in the pathway discussion to actively involve stakeholders in their decision-making process, many case studies continued to build technical data as a method for defending policies and actions. These results indicate that coastal adaptation can take-up adaptation pathways as a useful concept for decision-making and planning; however, many councils may still require assistance in stakeholder communication processes in order to develop sociallyacceptable plans that take into account the full range of values affecting local coastal environments.  相似文献   
784.
针对液化天然气(LNG)船舶通航影响问题,探索定量评估方法,采用多智能体仿真技术,并基于仿真建模平台,建立一套完整的评价指标。以嘉兴港LNG工程为例,本文提出的仿真模型利用智能体相互联系、实时交互的特点,对港口运营系统所涉及的各项要素进行模块化开发,能够科学、有效地模拟港口实际运作情况,定量得出LNG船舶对港口运营带来的影响。综合各指标分析后,认为嘉兴港LNG工程对其港口运营影响较小。  相似文献   
785.
李鹏  赵鹏  程瑾  王文博  李建 《水运工程》2018,(S1):43-48
针对东营港某港区在防波堤建设和航道疏浚施工同步进行的共同作用下的备淤深度问题,建立工程海域的潮流泥沙数学模型,对该模型进行了波浪、潮流、泥沙及地形冲淤验证。在数学模型的基础上,将施工过程分解为若干节点分别建模计算,并结合施工结束至竣工验收的不同时间分期叠加统计。得到同步施工期间航道的回淤规律并预测备淤深度。该研究为航道工程的顺利实施提供技术支持,也为解决此类问题提供参考。  相似文献   
786.
The optimal allocation of multiple land uses constitutes a complex multi-objective optimization problem with unknown feasible objective space and optimal planning alternatives. Despite the effectiveness of evolutionary algorithms to capture the underlying Pareto set of optimum maps, land use planners are bound to pursue the best possible spatial allocation of each use within an enormous population of non-dominated solutions. This article presents a novel post-processing methodology enhancing the comparative evaluation of alternative planning approaches without making any assumptions about the (relative) importance of each objective function. The proposed consolidated post-processing module is applied in a land use planning paradigm, revealing: (a) the existence of substantial planning guidelines whose validity is not affected by the relative significance of each criterion and (b) the variable planning component emerging from the (varying) relative importance of objective functions. Such planning feedback could not be extracted by the exhaustive review of non-dominated maps.  相似文献   
787.
为进一步提高软弱围岩条件下隧道开挖的安全性及稳定性,本文依靠玉磨铁路新平隧道工程,利用有限差分数值模拟软件flac3 D,对软弱围岩铁路隧道三台阶带仰拱一次开挖工法的台阶高度进行优化研究,主要对比了5种不同台阶高度开挖方案的初期支护位移及内力.结果表明:(1)采用工况4(上台阶高度4 m、中台阶高度3.2 m、下台阶高...  相似文献   
788.
对砂石路面坑槽产生的原因进行分析,并采取相应的措施进行防治,使砂石路面坑槽得到有效的控制。  相似文献   
789.
本文论述了十堰市旅游业发展现状 ,武当山在十堰旅游经济中的龙头地位及存在的问题 ,对大力发展以武当山为龙头的十堰市旅游经济的几点建议。  相似文献   
790.
黑龙江省公路涎流冰防治   总被引:1,自引:0,他引:1  
结合我省寒区特点,提出了公路涎流冰的防治原则,并分别对地面和地上排水措施进行了详细介绍。  相似文献   
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