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11.
Patterns in diversity and community structure of epipelagic copepods from the Brazil–Malvinas Confluence area, south-western Atlantic 总被引:1,自引:0,他引:1
Diversity and structure of epipelagic copepod communities were investigated using 70 zooplankton samples collected from the top 50 m of the Brazil–Malvinas Confluence area between 35° and 55°S. Biogeographic patterns were investigated using multivariate analysis. Biodiversity patterns were examined using different univariate indexes. Representatives of 35 species of copepods from 23 genera and 13 families were found. Two zones were delimited based on their copepod composition, one in the subtropical waters of the Brazil current, and the other in the subantarctic waters of the Malvinas current. Both environments displayed contrasting patterns of biodiversity depending upon which element is measured (regional species richness as well as mean point species richness were significantly higher in the subtropical group of stations, whereas taxonomic distinctness was significantly higher in the subantarctic community). Based on these contrasting results, we suggest the use of both kind of indexes when defining priority areas for conservation. 相似文献
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付昕瑶 《辽宁省交通高等专科学校学报》2015,(1):37-39
本文重点研究了对于B/S架构的软件在Windows7系统下部署时应该采用的一系列方法及在部署时遇到的一系列问题的解决方案。文中分析了利用ASP.NET开发的B/S架构的软件的优点并在此基础上介绍了软件部署的流程。本文在分析过程中结合具体实例提出了部署中一些常见问题的解决方案。 相似文献
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本文通过对C/S和B/S模式物资管理系统在使用中优缺点的分析,提出了采用以C/S模式为主,B/S模式为辅的混合模式对当前单一的C/S模式物资管理系统进行改造的设想。在这种混合模式下,物资管理部门内部采用C/S模式,便于实现复杂的管理功能及可靠的安全机制:对于非物资管理部门的用户,采用B/S模式,便于统一管理与维护。最后,本文还对系统改造的开发环境和技术做了探讨。 相似文献
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Observations of the Fawn Trough Current over the Kerguelen Plateau from instrumented elephant seals 总被引:2,自引:1,他引:1
Fabien Roquet Young-Hyang Park Christophe Guinet Frdric Bailleul Jean-Benoît Charrassin 《Journal of Marine Systems》2009,78(3):377
Due to its great meridional extent and relatively shallow depths, the Kerguelen Plateau constitutes a major barrier to the eastward flowing Antarctic Circumpolar Current in the Indian sector of the Southern Ocean. While most of the Antarctic Circumpolar Current transport is deflected north of the Kerguelen Islands, the remainder ( 50 Sv, 1 Sv = 106 m3 s− 1) must pass south of the islands, most probably through the Fawn and Princess Elizabeth Troughs. However, the paucity of finely resolved quasi-synoptic hydrographic data in this remote and infrequently sampled area has limited the progress in our knowledge of the regional circulation. Since 2004, a new approach using elephant seals from the Kerguelen Islands as autonomous oceanographic profilers has provided new information on the hydrography over the Kerguelen Plateau, covering the entire Antarctic Zone between the Polar Front and Antarctica, with a mean along-track resolution of about 25 km. These finely resolved bio-logged data revealed details of a strong northeastward current found across the Fawn Trough (sill depth: 2600 m; 56°S, 78°E). This so-called Fawn Trough Current transports cold Antarctic waters found mostly south of the Elan Bank, between the Ice Limit (58°S) and the Antarctic Divergence (64°S) in the eastern Enderby Basin, toward the Australian–Antarctic Basin. Our analysis also demonstrates that the Deep Western Boundary Current, which carries cold Antarctic water along the eastern flank of the southern Kerguelen Plateau collides with Fawn Trough Current at the outlet of the Fawn Trough sill. In other words, the Fawn Trough constitutes a veritable bottleneck, channelling the quasi-totality of the Antarctic Circumpolar flow found south of the Polar Front. Thanks to the unprecedented fine resolution of seal-borne data, a branch of flow centered at the Winter Water isotherm of 1 °C is also revealed along the northern escarpment of the Elan Bank, and then along the southern edge of Heard Island. Further analysis of different supplementary data reveals a complex circulation pattern in the entire Enderby Basin, with several distinctive branches of flow being strongly controlled by prominent topographic features such as the Southwest Indian Ridge, Conrad Rise, Elan Bank, and Kerguelen Plateau. This newly emerged frontal structure refines considerably previous large-scale circulation schematics of the area. 相似文献
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由于现代多样的电子控制技术和电子控制理论的迅猛发展,高精度的机械在各类工业控制系统、生产线等方面的需求越来越大.其中以单片机为核心实现的数字控制器,因其体积小、简便易行等优点,而被广泛应用于各行各业.本文将单片机的温度控制系统作为设计核心,通过温度传感器、单片机等软件系统图,并利用软件编程,从而达到实现水温控制的目的.... 相似文献
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Floating structures oscillate in waves, where these wave-induced motions may be critical for various marine operations. An important consideration is thereby given to the sea states at the planning and operating stages for an offshore project. The most important information extracted from a sea state is the directional wave spectrum, indicating wave direction, significant wave height, and wave spectrum peak period. Among several available methods of measuring and estimating the directional wave spectrum, the wave buoy analogy technique based on vessel motion responses is an in situ and almost real-time solution without extra costs of devices. If the forms of the wave spectra are not predefined in the estimation, the method is called a nonparametric approach. Its most remarkable advantage is the flexible form, but the smoothness should be regulated. After the discrete Fourier transform has been applied to the measured vessel motions, smoothing is necessary. However, this process results in disturbed vessel cross-spectra and a lowpass characteristic of the windowing function. This paper presents a nonparametric approach for directional wave spectrum estimation based on vessel motion responses. It introduces novel smoothness constraints using Bézier surface and includes a more robust estimate using L1 optimization. Both techniques are applied to the wave buoy analogy for the first time. Numerical simulations are conducted to verify the proposed algorithm. 相似文献
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《中国舰船研究》编辑部 《中国舰船研究》2016,11(1):0-0
[1] 航空母舰发展的思考…朱英富,熊治国,胡玉龙(1)[2] 水面舰艇作战系统的回顾和展望…潘镜芙,董晓明(8)[3] 发展绿色舰船,抢占未来舰船发展制高点…马运义(13)[4] 舰船装备保障流程管理…朱石坚(19)[5] 高强度钢在潜艇应用中的若干重要问题综述…杨建明,张新宇,刘朝骏(27)[6] 水下爆炸气泡及其对结构毁伤研究综述…姚熊亮,刘文韬,张阿漫,刘云龙(36)[7] 舰艇抗爆抗冲击技术现状和发展途径…刘建湖,周心桃,潘建强,王海坤(46)[8] 流致噪声机理及预报方法研究综述…王春旭,吴崇健,陈乐佳,邱昌林,熊济时(57)[9] 我国舰船中压直流综合电力系统研究进展…付立军,刘鲁锋,王刚,马凡,叶志浩,纪锋,刘路辉(72)[10] 石墨烯及其在金属防腐中应用的研究进展…龚佑宁,于连江,潘春旭(80)[11] 等离子体技术处理舰船固体废弃物的进展…吕东方,于开录,岳强(89)[12] 新概念穿梭艇自航模操控系统试验研究…王健,刘旌扬,魏成柱,李英辉,易宏(95)[13] 实验尺度无人水下滑翔机设计与试验…杨海,刘雁集,张凯(102)[14] 基于惯容器的机械振动被动控制系统传递特性分析…刘彦(108)[15] 基于数字样机的舰船维修性设计分析技术…方强,王松山,祝泓,张平(114)[16] 大型舰船物资转运瓶颈解析计算及分段优化方法…金迎村,宗砚,王皎(121)[17] 船舶纵向下水曲线直接计算法…林诗尧,孙江龙,曾荆州,解德(128)[18] 舰船集成冷媒水系统损害检测…徐新华,李伟光,谢军龙(135)[19] 《中国舰船研究》创刊10周年发展回顾及文献计量学分析…易基圣,喻菁,许建(143) 相似文献
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