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121.
Spatial fisheries ecology: Recent progress and future prospects 总被引:1,自引:0,他引:1
L. Ciannelli P. Fauchald K.S. Chan V.N. Agostini G.E. Dingsr 《Journal of Marine Systems》2008,71(3-4):223
We review recent progresses made in the study of fish distribution and survival over space — i.e., fisheries spatial ecology. This is achieved by first surveying the most common statistical approaches and relative challenges associated with the analysis of fisheries spatial data, loosely grouped in geostatistical and regression approaches. Then we review a selected number of case-studies implementing the discussed techniques. We conclude by proposing new areas of statistical and ecological research to further our understanding of how fish distribute and survive in space. This review serves a dual purpose by emphasizing the scientific importance of studying spatial interactions to better understand the temporal dynamics of fish abundance, and by promoting the development of new analytical and ecological approaches for the analysis of spatial data. Through our survey we cover different statistical techniques, marine ecosystems and life stages. This analytical, geographic and ontogenetic variety is also purposely selected to highlight the importance of comparative and multidisciplinary studies across diverging ecological disciplines, ecosystems and life stages. Besides having a general ecological relevance this review also bears a more applied significance, owing to the increasing need for protecting renewable marine resources along with their primary habitat. 相似文献
122.
To reduce the performance deterioration induced by imperfect channel state information (CSI) in cor-related multiple input multiple output(MIMO) downlink, the linear transmit/receive filters should be optimized to be robust to imperfect CSI. A sub-optimization algorithm based on minimizing sum MSE conditional on available imperfect CSI estimates subject to a per-user power constraint is proposed. The algorithm adapts the existing MMSE algorithm from uncorrelated single-user MIMO system with perfect CSI to correlated MIMO downlink with imperfect CSI. Simulation shows that the suboptimal algorithm can effectively mitigate the performance loss induced by imperfect CSI and has a good convergence performance. In addition, the effect of spatial correlation on the performance of the proposed algorithm is also simulated. 相似文献
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通过对北海堤围垦工程平面布置的研究,分析低滩围垦工程的堤轴线布置,研究低滩围垦平面布置形式,并通过数模试验进行验证。 相似文献
124.
单壳油轮将要逐步淘汰出油运市场,将其改造利用是一种比较理想的途径,文章主要介绍将单壳油轮改造成双壳油轮、双壳散货船、矿砂船等3种类型船舶改装的施工设计。 相似文献
125.
基于CATIA三维设计优势,将消防车各功能部件按照装配依从关系,以父子关系的方式建立一个桌面布局平台,在关键装配体的布局文件中建立子部件的定位平面、控制草图,以便在整个设计过程中对产品及各部件进行控制管理、调整结构布局、更改产品造型、测控载荷分布、优化设计方案等,达到高效、准确、优质的设计效果。 相似文献
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Kendra Ryan Alison Bates Morgan Gopnik Andy Danylchuk Adrian Jordaan 《Coastal management》2019,47(3):269-291
The United States contributes only 0.2% of the 18,814?MW of global installed offshore wind capacity. Lack of development has been attributed in part to a cumbersome regulatory process that includes the evaluation of environmental impacts. Assessments are based on biological, social, and technical data that are often incomplete. Marine spatial planning (MSP) may help fill data gaps. We conducted semi-structured interviews with key informants to understand (1) whether a lack of biological data impedes offshore wind environmental assessments, (2) whether MSP could mitigate these impediments, and (3) whether MSP could advance offshore wind development in the U.S. in other ways. Most informants stated that a lack of biological data in offshore wind environmental assessments was problematic due to incomplete data, uncertainty of data, and mismatched scales. Data issues may be mitigated by creation of data products and increased communication, outcomes of MSP that may benefit the regulatory process by increasing data availability, resolving conflicts among users, and providing a common operating picture. Challenges remain in integrating MSP into the processes of siting and permitting offshore wind, but it provides a strategic framework for the systematic identification, collection, collation, analyses, application, and management of data in the offshore wind environmental regulatory process. 相似文献
129.
大源渡航电枢纽拟增建鱼道,受枢纽总平面布置条件限制,鱼道进口如果布置在电站尾水,则施工难度和投资均较大,存在严重安全隐患。为既确保安全、节省投资,又满足过鱼要求,采用SMS-RMA2模型建立了平面二维水动力数学模型,模拟得出枢纽坝轴线下游一定范围内多种不同工况下的流场图,为在坝址所处微弯分汊河段找到合适的鱼道进口位置提供了可靠的参考依据。为提高过鱼效果,建议在鱼道进口上游侧设置导鱼电栅等拦鱼系统和喷淋水声、灯光等诱鱼系统,帮助鱼类及早发现鱼道入口。 相似文献
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