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51.
苏国 《城市道桥与防洪》2011,(8):169-172,14,15
2号线东延伸接驳段工程是整个东延伸项目的关键节点,在不影响运营通车的条件下进行下部结构改造是该工程的一个难点。该文根据桥墩在线路上的具体位置不同,结合现行加固规范并考虑实际情况进行分别设计,制定各自独立的改造方案。其成果对于其他改造工程,尤其是轨道交通高架接驳段工程具有一定参考价值。  相似文献   
52.
为解决多居住区共享停车场同时存在临时共享停车需求和提前预约共享停车需求的动态泊位分配问题,本文提出将未来几个时段的共享停车供需同时考虑到当前时段泊位分配中的单时段泊位分配方法,并将本时段泊位匹配结果延伸到后续时段,从而提出共享泊位动态分配流程。对临时停车需求,以用户成本最小为目标确立优先泊位匹配的原则;对预约停车需求,以系统收益最大为目标确立在当前时段结束时统一分配泊位的原则。定义4个指标评价模型效果。 选择来源于成都市某共享停车APP的3个居住小区一天的数据,对模型进行实证研究以及灵敏度分析。研究结果表明:临时共享停车需求和提前预约共享停车需求所占比例在0.4~0.6时,泊位分配后总目标表现最好;将未来几个时段的供需同时考虑到当前时段中,泊位分配效果更好,且考虑的未来时段越多,泊位分配后总目标越好;在泊位分配时,为了较好地保证临时停车需求能够优先分配到泊位,往往会造成总目标变差。  相似文献   
53.
This article has two goals: (1) to consider the underlying semantic confusion surrounding the promotion of “social science” in the design and establishment of marine protected areas and (2) to demonstrate the successful community processes that led to the designation of Sitka, Alaska's Local Area Management Plan (LAMP) for halibut fishing in the vicinity of Sitka. Uniting a collection of diverse “social” issues creates ambiguity in actual problem solving—extensive generalization can not resolve a specific issue. The Sitka LAMP is a specific case with clear details and a traceable history of success, designed to sustain the healthy status of Sitka's local halibut resource. The development of the Sitka LAMP designation demonstrates the importance of community collaboration and exhibits methods that could potentially be modeled in other locations.  相似文献   
54.
夏热冬冷地区重交通钢桥面铺装对钢板防护、混合料高温稳定性和低温抗裂性要求较高,同时需兼顾沥青混合料的耐久性和施工和易性。通过对全国典型钢桥面铺装的调研和分析,判断沙尔沁互通立交钢桥面浇注式沥青混凝土铺装设计的合理性,通过关键施工控制措施,使该种铺装结构在沙尔沁互通立交顺利实施。  相似文献   
55.
This article recommends the parallel but separate modeling of nature-based and people-based marine protected areas (MPA) before the design and siting stages of establishing an MPA. Separate but simultaneous modeling of ideal nature and people MPAs permits each to be maximized for its own variables and subsequently compared to identify conflicts and agreements. The case that supports this recommendation is in the Commonwealth of the Bahamas, where the study conducted 572 interviews with people from six traditional settlements in the central Exumas Islands and Cays. The research is focused on why members of these settlements differentially responded to three nearby national MPA proposals.  相似文献   
56.
Much has been written about the usefulness of marine protected areas (MPAs) as a management tool. Their performance has been measured using biological and ecological indicators. However, objectives of management also include economic and social responsibilities. As such, stakeholder objectives in MPA management are frequently incompatible. This has been attributed to the variety of stakeholders with an interest in how MPAs are managed. This article considers the development of a performance indicator hierarchy for the Egadi Islands Marine Reserve, and a multi-criteria approach implemented to define compromise positions between stakeholders in decision-making. Data was obtained from a pairwise comparison survey using the analytic hierarchy process to investigate preferences of stakeholder groups for performance indicators in evaluating marine protected area management. The analysis showed that although there are five key stakeholder groups, none are homogenous in prioritizing performance indicators and that none are clear with respect to what the MPA means for them.  相似文献   
57.
We have analysed the mesozooplankton community structure in the southern Bay of Biscay shelf and its relationship with the hydrographic conditions during spring 2004. According to thermohaline characteristics, we observed two frontal zones of distinct origin along the shelf (around 7° and 3°W), that allowed us to differentiate three different hydrographic domains. The westernmost part of the shelf (WC), defined by the presence of relatively warm and salty water related to the presence of the Iberian Poleward Current (IPC), the easternmost region (EC), characterized by colder and fresher water and subject to the influence of freshwater inputs from the Adour river in the French coast, and a region in the Central Cantabrian Sea (CC), where thermohaline characteristics were intermediate between these two extremes. The mixing layer depth (MLD) regime in these areas was also different: the WC region was characterized by a mixed water column, whereas in the EC region the river discharges produces stratification of the upper meters of the water column (< 10 m); in the CC region, we found a distinct vertical mixing regime that separated coastal (stratification) from shelf (mixed water column) stations, giving rise to a notorious across-shelf front. We found a good match between the aforesaid hydrographic regions and the distribution of mesozooplankton species composition and community assemblages: the Mantel correlation between physical variables and mesozooplankton distribution was highly significant (n = 63, r = 0.70, α < 0.001). In the WC region, the community was dominated by Paracalanus parvus, Oithona helgolandica, Acartia clausi and Clausocalanus pergens, while in the EC region the most dominant species were Noctiluca scintillans, Oncaea media and Temora longicornis. The CC region showed similar composition of copepods than the WC region, but larvaceans (Oikopleura spp. and Fritillaria spp.) were more abundant in the CC region than in the WC region. Within each zone, the relative abundances of the dominant species differed between coastal and shelf locations.  相似文献   
58.
Complex policy frameworks guide the management of the Great Barrier Reef (GBR) at multiple decision-making levels. Mounting pressure on its outstanding universal value suggests that further improvements in governance are required. There has been little examination of the role of policy actors in addressing complex governance challenges in large scale marine protected areas (LSMPAs) involving multi-layered governance conflicts across diverse contexts. Framed by street level bureaucracy, pragmatic planning theory, and lessons from MPA governance, this paper examines how policy actors improvised and collaborated to advance outcomes in the GBR LSMPA. We assessed practice-focused oral histories with experienced policy actors who negotiated agreements and achieved policy outcomes in the GBR between 1985 and 2016. These policy actors were skilled improvisers, alternating between roles as democratisers, mediators, and negotiators. They used collaboration and facilitative leadership to advance policy in the face of governance problems. This enabled them to adapt policy across multi-level decision systems, address power and information imbalances, and generally deal with conflict and uncertainty. A deeper understanding of improvisation will assist governments and others to address complex challenges in LSMPAs.  相似文献   
59.
针对内蒙古自治区S209线粉土地区沿线土质调查研究和现场室内承载比试验资料,介绍了室内CBR隹试验技术及粉土作路基填料的不合理性。  相似文献   
60.
研究了以黑龙江省为代表的寒区高等级公路交通安全特性。针对寒区高等级公路交通事故时间分布、事故形态分布等进行了成因分析,提出了相应的交通安全改善对策。  相似文献   
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