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111.
与普通高速公路相比,山区高速公路的交通安全问题更为突出.鉴于此,分析现阶段山区高速公路事故多发的原因,研究山区高速公路的线形设计、视觉和气候等方面的因素对交通安全的影响,探讨减少山区高速公路交通事故的具体措施,以达到加强安全管理、降低交通事故率、减少经济损失的目的.  相似文献   
112.
Adapting to changing coastlines is an unprecedented planning challenge as coastal hazards, including those associated with climate change, influence all areas of resource management. Tools have been developed to aid in understanding coastal hazards and to facilitate the planning and implementation of adaptation strategies. Through interviews with members of eight geographically distributed state Coastal Zone Management (CZM) Programs and several federal and nonprofit partners, we explored the utility of current tools for on-the-ground adaptation planning and implementation needs. State CZM Programs operate as trusted information brokers at the nexus between national resources and local needs. Here we provide seven recommendations for how to overcome the challenges identified with tool discovery, lack of trust, and the coarse spatial resolution of national tools. Our findings suggest local community needs are better addressed when end-users play a role in the tool development process. We also recommend leveraging CZM Program connections because they have the knowledge and expertise to identify solutions and disseminate information. While the recommendations presented here were taken from the perspective of state CZM Programs regarding coastal tools, the lessons learned may provide valuable insight into the tool development process for other resource management fields.  相似文献   
113.
The current approach to coastal development set-back delineation in South Africa is producing high-tech empirical methodologies that attempt to pinpoint areas at risk from physical coastal processes and the subsequent positioning of set-backs in relation to these risk areas. Experience in the Western Cape province of South Africa has shown that this approach contributes only partially to coastal risk management. In the context of an urban and peri-urban environment, and bearing in mind that set-backs have significant socioeconomic implications, the development of a set-back line at the local scale requires an expansion beyond just relying on the numerical modeling of physical coastal processes. This research reveals that such an approach is parochial and socially detached and a more inclusive and integrated approach grounded in and spanning localized social, cultural, economic, political, and ecological intricacies of the coastal space is required. Fundamental to achieving this is a re-consideration of the broader project management processes applied in the development of set-backs. The article concludes with a set of principles and guidelines for determining set-backs in complex coastal contexts at the local scale.  相似文献   
114.
石灰土强度形成受气候等条件影响,特别在南方多雨地区,地下水位较高,土含水量大,石灰土施工中合理的控制措施非常重要。该文结合上海市中环线浦东段道路工程中石灰土的施工,在对上海地区气候条件分析的基础上,对石灰土施工的准备阶段、施工阶段、养护阶段等环节的控制要点进行了系统总结,可为南方地区石灰土施工提供参考。  相似文献   
115.
笔者基于对新疆国道 2 18线和省道 313线道路翻浆的长期现场观测和研究 ,比较客观地构筑了道路翻浆发生的物质环境 ,即路床中 4 0 %左右的粘土含量和 2 5 %左右的含水量 .道路翻浆可以分为气候翻浆和动力翻浆两大类型 ,路床中存在粘土透镜是翻浆发育的必备条件 .翻浆鼓丘是道路翻浆的直观体现 .翻浆鼓丘呈椭圆形及圆形 ,椭圆形鼓丘主要出现在平直公路段 ,圆形鼓丘主要出现在弯曲公路段 .路基中道路翻浆通常发生在路面基层以下 30— 4 0cm的路床范围内 .根据鼓丘龟裂纹可以反演翻浆类型 ,并判识粘土透镜的位置 .  相似文献   
116.
The integration of climate change adaptation considerations into management of the coast poses major challenges for decision makers. This article reports on a case study undertaken in Christchurch Bay, UK, examining local capacity for strategic response to climate risks, with a particular focus on issues surrounding coastal defense. Drawing primarily on qualitative research with local and regional stakeholders, the analysis identifies fundamental disjunctures between generic concerns over climate change and the adaptive capacity of local management institutions. Closely linked with issues of scale, the problems highlighted here are likely to have broad and continuing relevance for future coastal management elsewhere.  相似文献   
117.
The “no net wetland loss” goal has not been met in urban coastal regions where conditions continue to exacerbate wetland losses. Under the Clean Water Act (Section 404) the U.S. Army Corps of Engineers and U. S. Environmental Protection Agency share responsibility for regulating placement of fill material in wetlands. The `no discharge of fill' rules threaten coastal wetlands with continuing losses due to effects of changing climate, including rising sea levels, higher storm surges, and flooding. Where inland migration is limited by development, or where sediment accretion rates are lower than the rate of sea level rise, urban wetlands will be lost unless marsh topography is elevated. We explored regulatory and design approaches in recent Hudson-Raritan Estuary (HRE), San Francisco Bay Estuary and coastal Louisiana restorations, including creation of new marshland using dredge material. Questions related to sea level rise, ecological position within the landscape, or potential effects of extreme storm events were not addressed in the HRE restoration designs; these concerns were taken into account in other regions. We suggest benefits of marsh `replenishment' should be acknowledged in Federal regulatory policy and that consistent policies supportive of low-lying coastal marsh preservation in all regions should be enacted.  相似文献   
118.
Abstract

Marine and coastal zone policy represents a collaboration of people managing and people managed. This paper takes a holistic stance in suggesting that marine communities are viewed properly as networks of focused interest groups, policymakers, professionals, and publics. The interplay between culture and marine and coastal policy is appropriately one topic of applied social research. Seven ethnographic studies in this domain are introduced in this theme issue and help us to understand sociocultural processes and institutions bearing on marine affairs.  相似文献   
119.
针对中美联合教育项目留学生在美国大学校园生活和学习的适应状况,本研究从多维的角度调查项目学生在学业方面遇到的主要问题及学生的性别、年龄、教育层次、在美时间等因素对学生文化学习适应的影响;调查项目留学生在美大学校园文化生活满意度与其对美国的态度、思乡、文化休克之间的关系,以期为国内大学发展与之相关的出国留学生适应辅助项目提供支持,为留学生出国前的语言培训、学业和心理准备提供帮助。  相似文献   
120.
基于等效光幕亮度理论的隧道入口段亮度计算方法   总被引:1,自引:0,他引:1  
为了获得更加合理的隧道入口段亮度设计值,首先分析了隧道入口段亮度的确定方法,指出了Adrian和Augdal提出的等效光幕亮度计算方法中,都因为忽略了某些计算项而造成得到的极坐标圆环边界视角存在一定的误差;为解决该问题,提出采用数值积分的方法确定各圆环边界的对应视角,并给出了计算得到的各圆环边界视角值和由此得到的等效光...  相似文献   
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