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381.
芜申航道南京高淳段护岸结构形式的探讨 总被引:3,自引:0,他引:3
航道整治中采用生态护坡是恢复航道生态的基础。介绍芜申航道南京高淳段整治工可报告中设计的航道护岸结构形式和国内外目前的一些生态护坡技术,并根据芜申航道高淳段的特点,探讨几种可考虑采用的生态护岸结构形式。 相似文献
382.
以灌河口整治工程为例,采用大范围二维水动力数学模型,从定性、定量两方面分别研究了航道单纯疏浚工程及布置单、双导堤工程(结合疏浚)对潮汐动力为主河口地区入海河流纳潮量的影响,并就导堤高程对纳潮影响进行了探讨。研究结果表明,灌河口航道单纯疏浚工程会增加灌河纳潮量,增设单导堤后纳潮量将会进一步增加,而双导堤工程后,灌河的纳潮量既有可能增加也有可能减少,主要取决于导堤高程。就导堤高程对于灌河纳潮量的影响来说,东导堤高程位于低潮位及涨急附近潮位时最为敏感,而西导堤各级高程都较为敏感。方案比较显示,只要堤顶高程控制合理,灌河口双导堤工程实施以后可以保持灌河纳潮量基本不变。 相似文献
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384.
In this article we use a multi-scale, multi-method historical reconstruction of post– World War II social-ecological interactions within fisheries in Newfoundland and Labrador to explore the dynamics of intensification, expansion, and resource degradation in managed fisheries. Our case study draws on landings statistics, other archival information, and the Local Ecological Knowledge (LEK) of fish harvesters to explore these linked dynamics at the macro, meso, and micro levels. By some measures we found large scale trends toward intensification of effort leading to over-harvesting at macro (province wide) levels. At the same time, at the local level (micro-scale) and across sectors and regions (the meso-scale), we found highly fluid fishing practices and a complex suite of stated motivations for change. As a basis for effective governance, an understanding of the dynamics of interactive restructuring in social ecological systems will require multi-scale analyses that are sensitive to this complexity. 相似文献
385.
鄱阳湖生态经济区文化软实力建设是提升鄱阳湖生态经济区整体实力和竞争力的必然要求,是指基于已有文化资源,通过采取相应举措,增强其内在的凝聚力、生命力、创新力和外在的感召力、吸引力、影响力。丰富的文化资源是文化软实力建设的基础。鄱阳湖生态经济区文化资源转化为文化软实力还面临内在凝聚力不强、对外传播力不大等诸多困境,提炼核心价值观、加强传播力度、推进资源开发、吸纳优质人才、强化合作交流、构建长效机制是破解困境之策。 相似文献
386.
The objective of this article is to take stock of integrated management in the Canadian North, assessing its contribution to the advancement of knowledge and practice regarding the role of indigenous knowledge and community-based monitoring. This is done in three steps. (1) The Beaufort Sea, designated a Large Ocean Management Area under Canada's Oceans Action Plan, is used as an example of a consultative planning process, with special attention to indigenous peoples. (2) How specifically can indigenous knowledge contribute to integrated management? The problem of Arctic marine food web contamination is used to illustrate the strengths and limitations of traditional ecological knowledge and its relationship to science. (3) The discussion of community-based monitoring relies on Voices From The Bay study involving the Inuit and Cree of Hudson and James Bay, and Inuit observations of climate change study in the Canadian western Arctic. The examples together address integrated coastal management and the health of ocean ecosystems, showing how stakeholder participation and knowledge helps widen the range of knowledge to understand and help monitor environmental change. 相似文献
387.
Mou Jianjun Liu Zhiquan Yang Dingyi) Department of Cardiovascular Internal Medicine First Affiliated Hospital Xi′an Medical University Xi′an 《西安交通大学学报(英文版)》1999,(2)
Insulinresistanceandcompensatoryhyperinsulinemiawerefrequentlyfoundincaseofessentialhypertensionsuggestingthatinsulinisinvolvedinthepathogenesisofhypertension〔1〕.Sodiumsensitivitywasoneoftheintermediatephenotypesofessentialhypertension.Evidencesuppor… 相似文献
388.
纪宁毅 《船舶标准化工程师》2013,(6):22-25,28
采用虚拟样机仿真分析软件ADAMS,建立了某型号船用低压框架式断路器系统的参数化模型。通过对该船用低压断路器系统运动特性的动态仿真分析,证明了模型的正确性。针对带载合闸过程中存在的触头间易产生拉弧现象,对动力系统中各弹簧的技术参数进行设计研究分析,获得各参数对断路器系统的影响灵敏度。针对各参数灵敏度高低的不同,以动触头转动角速度为优化目标函数,完成该断路器动力系统的优化设计分析。优化后的系统缩短了触头间的燃弧时间。该分析对于提高产品的安全可靠性和使用寿命具有指导意义,也为进一步的产品开发与优化设计提供了良好的平台。 相似文献
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390.
Abstract Given stochastic features of the demands on both the major road and the minor road at an at-grade un-signalized intersection, the capacity of the minor road is viewed as the vulnerable and critical part impacting on the overall capacity of the intersection. To facilitate the analysis of intersection performance reliability, the capacity reliability of the minor road is defined as the probability that the capacity of the minor road can accommodate a certain traffic demand at a certain degree of saturation. The headway distribution of traffic stream on major road is reflected by three types of distributions, namely, exponential distribution, shifted exponential distribution, and Cowan's M3 distribution. Based on field observations, the volumes on both major roads and minor roads are treated as correlated normal random variables. This paper presents the methods for modeling capacity reliability of the minor road at an at-grade un-signalized priority intersection. A method based on first-order reliability method is used to model the capacity reliability index. As important associated factors of capacity reliability analysis, the methods for modeling and analyzing capacity sensitivity of the minor road and reserve capacity of the priority intersection are also presented. A procedure for evaluating the intersection potential performance using capacity reliability, sensitivity and reserve capacity is developed and demonstrated with a numerical example. Finally, some new findings from the case studies are summarized. 相似文献