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91.
The planning and development of pedestrian and cycling amenities in coastal urban environments is a challenging process because a wide range of policies and considerations must be taken into account. Among these, the concepts of sustainability and more recently, resilience, have been gaining prominence. Green Infrastructure design approaches can integrate aspects of both sustainability and resilience, providing multiple services within single development projects. This study focuses on Dublin and examines a range of amenity projects at various stages of development that relate to the provision of new coastal walking and/or cycle routes. These are initially contextualized at the city level before focusing specifically on challenges and benefits associated with the design and implementation of such projects. Based on our findings, recommendations are made for optimizing the potential of future projects to effectively integrate with other initiatives so as to deliver broader policy objectives. A simple sequential model is presented that should assist developers and decision-makers to take a more integrated, multidisciplinary approach to meeting policy goals when planning and developing coastal amenities. Finally, this is remodeled into a set of considerations that are generally applicable to coastal development proposals of significant scale.  相似文献   
92.
殷宗学 《船舶工程》2015,37(10):77-83
对电力系统几种常用的接地方式进行分析比较,得出海工中压电力系统最适合中性点经高电阻接地的结论。在介绍分析高电阻接地的主要连接方式和接地故障电流电路模型的基础上,阐述接地设备参数选取的计算方法与原则。并结合实例,演示了单相接地故障电流和接地电阻/变压器参数计算及接地保护装置参数设定的全过程,为大型海洋工程和船舶中压系统接地方案的选择、系统设计和实际应用提供了较为全面的理论依据和有益参考。  相似文献   
93.
付中敏 《水运工程》2015,(7):114-118
软体排边缘床面易受不利水流冲刷下切,当冲刷下切强度超过排体变形能力时,软体排排边会出现变形破坏。分析了护底软体排变形破坏的主要影响因素:水流条件、河床组成、软体排自身结构、余排宽度及施工工艺等。探讨了护底软体排破坏的力学机理。提出在排边一定范围内抛投一定密度的扭双工字型透水框架,能削减排边近底层的流速及紊动强度进而减弱或抑制排边冲刷,从而维持软体排结构安全及坝体稳定的应对措施。  相似文献   
94.
对土工格室的特点和抗滑稳定性的分析表明,在安全系数不小于1.5的条件下,土工格室是一种有效的边坡防护形式。土工格室护坡主要有平铺式护坡和叠砌式护坡两种形式。  相似文献   
95.
通过一系列的实验,研究开发了一种无毒环保类沥青阻燃剂,在基本不改变沥青性能的前提下,可以显著地改善沥青的阻燃性能。  相似文献   
96.
Abstract

The focus of this paper is theoretical, as well as methodological. It reviews previous studies of visual impact and reports research by the author on people's evaluation of the appropriateness of different man‐made facilities in different coastal‐area contexts and other environments. In this study, subjects were asked to react to slides developed through the use of landscape models and experimental facilities to simulate the appearance of a building in the landscape, while systematically varying the visual relatedness between the two. Specific interest centered on the variable of congruity vs. contrast between the appearance of the building and its landscape context, manipulated by co‐varying the attributes of color and size to create a five‐point scale of contrast/obtrusiveness. The hypothesis was that judgments of appropriateness, and to a lesser extent judgments of liking, would vary inversely with level of contrast. The role of two further variables, the functional significance of the building in its setting, and the character of the setting itself, was also investigated. The author reviews methodological issues involved where subjects respond to visual stimuli for purposes of judging change in visual quality. These methodological issues include: stimulus‐selection and problems of simulation, choice of response measures, and choice of respondents, and the treatment of individual differences. The author calls for development of standardized scales and indices such as “perceptually‐relevant environmental quality indicators.”  相似文献   
97.
Abstract

Seaport expansion often generates tensions between the national interest in efficient transport and local interests in water quality and habitat preservation. The governing American permitting system, however, establishes an extraordinarily cumbersome, legalistic, and costly method for balancing environmental and economic considerations. A case study of the Port of Oakland illustrates the tendency. For four years, plans to find an environmentally acceptable site for dredged material have been stymied by a sequence of inconclusive regulatory and judicial proceedings. Meanwhile, large container ships can enter and leave Oakland harbor only at high tide, and not fully loaded. Despite the absence of any authoritative determination concerning environmental risks, the port was compelled to accede to progressively more expensive disposal methods. Such “adversarial legalism”; is not unique to the Oakland harbor case, but recurs in other policy spheres. It stems from a governmental structure that fragments decision‐making power among many agencies, that constrains regulatory discretion with legal demands for scientific certainty, and that by allowing agency decisions to be challenged readily in court, encourages legalistic defensiveness and extortion rather than compromise. The article concludes with a discussion of the conditions under which regional planning bodies might overcome these centrifugal tendencies.  相似文献   
98.
很多铁路信号系统,特别是轨道电路的发送、接收和CAN总线均采用悬浮结构。为了防止出现第三轨问题,雷电防护方案中只加装差模(横向)防护用SPD,共模(纵向)防护是靠系统绝缘特性来承担。可是在实际应用中出现雷击损坏现象多是因为缺少共模防护。通过科研试验数据和现场雷害调查结果,综合分析该类悬浮系统共模雷击损坏特点,并针对防止出现第三轨问题,提出新的共模雷电防护方案供大家参考。  相似文献   
99.
船舶噪声对船员的听力损伤是众所周知的,甚至发生部分船员的永久性听力损失。国际海事组织第91届海安会通过了新的《船上噪声等级规则》,围绕实施噪声规则,分析了听力保护的技术要求和正确选用听力保护器的技术依据,探讨了佩戴听力保护器对语言交流和感受听觉信号造成的影响。强调必须开展听力损伤的风险评估,并对识别听力损伤的特殊风险因素提出了建议。  相似文献   
100.
深圳地铁2号线东延段安托山站—侨香站区间隧道顺利通过富水砂质地层的工程实例表明,在复杂地层中采用地面降水、超前预注浆及水平旋喷桩加固等辅助措施是成功的,也是必要的;另外,在隧道下穿次高压燃气管施工中,采用悬吊保护措施也为矿山法隧道施工和管线的绝对安全带来了技术保障。  相似文献   
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