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331.
主要介绍全国沿海港口码头综合通过能力和全国沿海港口2001—2005年建成投产项目情况,初步分析我国沿海港口发展和建设存在的问题,提出当前沿海港口发展和建设的意见与建议。  相似文献   
332.
为研究滨海特大高架桥梁地震反应性能,分析下部结构的影响,优化桥梁设计,为工程抗震设计提供参考.以工程实例为对象,建立三维动力模型,分析不同墩柱尺寸和桩基方案对桥梁地震反应的影响,并对桥梁进行延性抗震设计验算.结果 表明:随着墩柱尺寸和桩基数量增加,虽然其自身承载能力会变大,但同步地震反应也会增大;因此,需要选取经济合理的截面尺寸和桩基数量;根据分析选取的两项设计参数,在地震作用下,可以很好的满足延性抗震设计要求.  相似文献   
333.
刘庆诚   《现代交通技术》2012,9(5):23-25
水泥掺入量是水泥土设计的重要参数,直接关系到受加固地基的整体强度和工程成本。文章针对厦门集美临海区域淤泥土特性,通过室内配比试验和力学特性分析,考虑了3种常用水泥,研究水泥掺入量对水泥土强度的影响,并提出了水泥土抗压强度与掺入比的关系式,可为类似土质的水泥土设计提供参照。  相似文献   
334.
This study was designed to evaluate different approaches to the protection of the environments of coastal recreation sites in and around Antalya, Turkey. Data was collected by means of a survey of coastal recreation sites and six categories were evaluated: environmental protection, infrastructure facilities, water conservation, energy conservation, waste management, and protection of the natural environment. The results indicated that there was a clear motivation among site managers or authorities for environmental protection (p < .05), infrastructure facilities (p < .001), water conservation (p < .05), energy conservation (p < .05) and the protection of the natural environment (p < .001) but waste management was not accorded a priority. The quality of coastal recreation largely relies on the attractiveness and naturalness of the environment. Although good quality site management largely depends on the awareness and willingness of individual site managers, more proactive approaches toward better environmental protection of recreation sites along the Turkish Mediterranean coast might be effective in improving their sustainable use, particularly in the absence of proper site planning.  相似文献   
335.

I investigated the impact of human trampling on Fucus gardneri populations at Cattle Point on San Juan Island, Washington. I hypothesized that damage to Fucus fronds would differ depending on hydration state of the plants, number of trampling steps, and time. Over a two-day period, two levels of trampling treatment, 100- and 200-steps, were applied to 18 plots on two rocky intertidal benches. Detached biomass resulting from trampling was collected each day, weighed to the nearest 0.1 gram, re-hydrated overnight in seawater, and re-weighed in order to calculate biomass removed as a function of mean percent Fucus within each plot. Damage to plants did not differ with the hydration state of Fucus. However, loss of biomass did increase with treatment level, with 222 g of Fucus fronds removed from one 100-step plot up to 1302 g removed from a 200-step plot. Percent cover decreased differentially with treatment level, ranging from 10 percent cover in a 100-step plot up to 85 percent loss in a 200-step plot. To determine the effect of hydration on loss of Fucus biomass, future studies should include plants with a higher degree of desiccation than those in this study, more samples to increase the power of the analysis, and a longer period to detect changes due to time.  相似文献   
336.
文章针对广西北部湾港口保税物流业务培训现状,介绍了德国、新加坡职业培训模式及其共性和特点,分析了广西北部湾港口保税物流业务培训中存在的问题,并提出完善广西北部湾港口保税物流业务培训的相关措施。  相似文献   
337.
Abstract

Abstract This case study, prepared by an interdisciplinary group of several scientists and planners and a lawyer, reviews the handling by the decision process of an application to the Baltimore District Corps of Engineers for permission to construct a marina. The study determines that while the project in question may not present a significant environmental threat, the project when considered in conjunction with other pending projects on the same subtributary would contribute to boat congestion and degradation of water quality. Changes in the decision process are suggested which would facilitate consideration of the cumulative impacts from a series of coastal alterations.  相似文献   
338.
Abstract

A power plant siting procedure which accounts for the protection and preservation of aquatic resources, defined as sensitive life forms and life stages of economically valuable species of finfish and shellfish, is presented as it was executed on Maryland's Eastern Shore. Negative effects of power plant development and operation are generated principally by the cooling water intake and discharge system. The site‐selection procedure is thus presented as a two‐faceted process, termed regional screening, requiring the separate but simultaneous identification of land‐based sites and cooling systems. Criteria included in regional screening for cooling systems reflected life‐sustaining processes essential to the maintenance of aquatic resources. Major sources of effects of power plants on aquatic resources and siting principles as they affect aquatic resources are defined. Information‐gathering techniques included extensive interviews with key research scientists, state personnel, and numerous Chesapeake Bay watermen.  相似文献   
339.
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   
340.
本文在分析福州南动车运用所所承担的动车组检修任务及在铁路网布局定位的基础上,对进出段线采用灯泡线疏解方案的必要性、可行性进行了分析,并结合地形特点提出了不同的灯泡线疏解方案,在进行技术经济比较后,得出了经济可行的方案。  相似文献   
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