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排序方式: 共有989条查询结果,搜索用时 15 毫秒
81.
淮安三线船闸上下游引航道驳岸大量采用连续沉井结构,文章介绍了淮安三线船闸的结构特点,连续沉井的准备、制作以及下沉等工艺流程、施工要点与质量控制,同时也介绍了连续沉井与一般沉井下沉的不同点。 相似文献
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浅地层剖面探测与地震映像法探测的应用对比和分析 总被引:1,自引:0,他引:1
从应用原理、工程实例、应用效果分析等方面,对比分析浅地层剖面法和地震映像法的勘探特点.通过具体的工程实例,对比分析浅地层剖面法和地震映像法在海域覆盖层(软土层)的沉积序列类别划分、海底基岩面勘探、海底基岩突变处(暗礁、风化深槽等)、海底管线探测等方面的应用效果,辩明2种物探方法的优缺点和互补性. 相似文献
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Two major environmental problems currently affecting the Louisiana coastal zone are a high rate of wetland loss and high levels of surface water pollution. The application of secondarily treated wastewater to wetlands can be a means of dealing with both of these problems. The benefits of wetland wastewater treatment include improved surface water quality, increased accretion rates to balance a high relative water level rise due mainly to subsidence, improved plant productivity and habitat quality, and decreased capital outlays for conventional engineering treatment systems. Wetland treatment systems can, therefore, be designed and operated to restore deteriorating wetlands. Hydrologically altered wetlands, which are common in the Louisiana coastal zone, are appropriate for receiving municipal and some types of industrial effluent. While the U.S. Environmental Protection Agency has determined wetland wastewater treatment is effective in treating municipal effluent, it has discouraged the use of natural wetlands for this purpose. At the same time, funds are being used for the construction of artificial wetlands to treat municipal effluent. In the Louisiana coastal zone, however, wetlands are deteriorating and disappearing due to hydrological alteration and a high rate of relative sea level rise. If no action is taken, these trends will continue. Effluent discharge to existing wetlands should be incorporated into a comprehensive management plan designed to increase sediment and nutrient input into subsiding wetlands in the Louisiana coastal zone, improve water quality, and result in more economical waste‐water treatment. The authors believe that the Louisiana example serves as a model for other coastal areas especially in light of projections of accelerated sea level rise. 相似文献
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Abstract A territorial sea comprising 6.7 million acres of offshore lands extending three geographic miles into the Atlantic Ocean three marine leagues (nine geographic miles) into the Gulf of Mexico makes Florida the second largest “oceanowning”; state in the contiguous United States. Florida's history, climate, economic development, and worldwide reputation have evolved from the state's relationship with the sea. The state is now becoming aware that aggressive management of its ocean resources is necessary to preserve the future of that relationship. The purpose of this article is to present some of Florida's recent legal and policy initiatives that have been directed toward better understanding and management of ocean resources and uses. 相似文献
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Previous optimum multiparameter analyses have investigated spatial distribution of water masses and reported successful results. This study tests the method further with application to a time series to examine temporal variability in water mass distribution. Observations collected from the Sargasso Sea are utilised, mainly to detect well-documented property changes that have occurred in Labrador Sea Water, but also possible fluctuations in water mass contributions as a whole.The results show much structure and variability in the contributions of Central Water and upper deep waters in the depth range 900–2000 m. It is proposed that the passage of warm and cold core eddies is indicated by these changes in relative contributions of water masses, although quantitative comparison of satellite altimetry data with the model results is not conclusive.Significant irregularities in the distribution of Labrador Sea Water are also revealed by the model. Through-flow of modified (since the early 1990s) Labrador Sea Water is denoted in the results by an apparent absence from mid-1995 to early 1998. This suggests a transit time of 5–6 years between the Labrador Sea and Bermuda, which is consistent with observational findings described in the literature. 相似文献
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66—10系列空气压缩机被广泛应用在舰艇上,因其冷却系统采用开式循环,所以经常被海水腐蚀造成故障,文章针对这一现象进行了改装方案的设想,将冷却系统改为闭式循环,便可杜绝这一故障的发生。 相似文献
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介绍八维通科技有限公司已建的智慧出行数字票务服务平台的体系架构,并创新推出在交通出行大互通大覆盖需求下的智慧出行MaaS大数据云平台的构架设计。智慧出行MaaS大数据云平台采用企业运营数据中台的模式构架,以标准化采集为基础、开放架构为抓手、数据总线为主线,标准化的数据为基石、TT大脑为指挥中枢,安全可靠的支付服务为宗旨。云平台构架着重将差异化的需求进行共性化抽象,实现差异化的服务内容和不同支付方式接入时进行统一规范的运营支撑。目前,云平台构架和功能已在近20个城市上线运营和商用,验证了云平台构架的合理性和可靠性。 相似文献