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381.
Widely distributed on tidal flats on the west and south coast of Korea, the long arm octopus Octopus minor is one of the important shellfish resources, as 相似文献
382.
Arctic oscillation and the antarcic oscillation modes in the atmospheric stratosphere 总被引:1,自引:0,他引:1
QU Weizheng HUANG Fei ZHAO Jinping YANG Liang HE Hui DENG Shenggui CAO Yong 《海洋学报(英文版)》2005,24(6):46-53
1IntroductionThompson and Wallace(1998)first found the AOin1998and according to their definition,the spatialpattern of AO from the first EOF mode for the sea lev-el air-pressure(SLP)was that around the North Poleregion there was an oscillation out-of-phase with thatat the mid-latitudes zone.This oscillation had verywide frequency range from interannual to interdecadaltime scales.The AO is similar to the North Atlantic oscilla-tion(NAO)over the Atlantic.As Wallace said,theNAO could be… 相似文献
383.
384.
Tripod measured residual currents and sediment flux: Impacts on the silting of the Deepwater Navigation Channel in the Changjiang Estuary 总被引:3,自引:0,他引:3
Four bottom-mounted instrument-equipped tripods were deployed at two sections spanning the region characterized by severe sedimentation rates in the Deepwater Navigation Channel (DNC) along the North Passage of Changjiang Estuary in order to observe currents, near-bed suspended sediment, and salinity. Seaward residual currents predominated in the up-estuary section. In contrast, a classical two-layered estuarine circulation pattern occurred in the down-estuary section. Flow moved seaward in the upper layer and a heavier inflow, driven by the salinity gradient, moved landward in the lower layer. The near-bed residual currents in the up-estuary section and the down-estuary section acted in opposing directions, which implies that the region is a convergence zone of near-bed residual currents that trap sediment at the bottom. The maximum salinity gradient at the maximum flood current indicates the presence of a strong front that induces sediment trapping and associated near-bottom convergence of sediment, which explains the high sedimentation rates in this section of the estuary. 相似文献
385.
InSAR detection of residual settlement of an ocean reclamation engineering project: a case study of Hong Kong International Airport 总被引:1,自引:1,他引:1
Qing Zhao Hui Lin Wei Gao Howard A. Zebker Albert Chen Kin Yeung 《Journal of Oceanography》2011,67(4):415-426
Man-made land or islands that are reclaimed from the sea are suitable for building airports, harbors, and industry parks for
material transportation because of their broad air and land spaces. However, the reclaimed foundation settlement process is
of public concern, including the continuous impact of ocean processes on its stability. The majority of the buildings and
facilities of Hong Kong International Airport (HKIA) are built on a reclaimed foundation. The reclaimed foundation has been
in residual settlement since completion of the filling project in 1994. In this study, we use persistent scatterer interferometry
(PSI) and ENVISAT (European Satellite) advanced synthetic aperture radar (ASAR) data to detect the residual settlement rates
from 19 April 2006 to 9 January 2008. We use ground truth data to develop empirical correction models for correcting systematic
biases in the ASAR PSI-detected settlement rates. The corrected data follow the Lorentz distribution well, implying that the
residual settlement process is dominated by two modes or categories of settlement rates. The first category represents a relatively
stable state and the second category represents a continuous settlement state. A ground settlement rate map of HKIA shows
that an area of the Passenger Terminal Building and an area of the Southern Runway are two relatively stable areas. There
are two major continuous settlement areas. One covers the airport Midfield. Another is along the coastline, implying that
attention should be paid to impacts of ocean processes on the stability of airport foundations. 相似文献
386.
青海可可西里自石炭纪以来经历了复杂的构造演化和地表过程,形成了集高山、宽谷、夷平面、冰川、热泉、河流和湖泊等地貌元素为一体的高原高寒地貌,同时还包括了蛇绿混杂岩带、活动断裂带、地震遗迹和火山遗迹等地质元素。在调研前人研究资料和实地野外考察基础之上,根据IUCN(2005)提出的13类地质主题分类标准将区内的地质遗迹分为地质构造、火山和地热遗迹、山脉、地层剖面、河流和湖泊、现代冰川、冰期遗迹7类,共计60余处地质遗迹点。可可西里地质遗迹对重建古特提斯构造域、研究天然地震机制、青藏高原北部隆升过程及全球气候变化均具有重要的意义。基于可可西里区内地质遗迹和前人资料恢复出可可西里石炭纪以来经历了8个构造演化阶段。 相似文献
387.
结合固定翼飞机与潜器设计原理设计了一种密度大于水的潜器——重水潜器,它利用机翼升力平衡剩余重量,外形就像固定翼飞机.由理论分析可知在有效载荷和航行速度相同的情况下重水潜器较常规潜器的体积有明显减小,而以中高速航行时重水潜器阻力优势明显.根据固定翼飞机与潜器设计原理相结合的设计方法制作的重水潜器样机进行水池试航时顺利完成直航、水平回转、爬升、下潜等规定动作,并表现出良好的稳定性和操纵性,从而证明了该设计方法的可实现性. 相似文献
388.
-The hydrodynamic forces on a smooth inclined circular cylinder exposed to oscillating flow were experimentally investigated at Reynolds number (Re) in the range 40000-200000 and Keulegan-Capenter number (KC) in the interval from 5-40. In the test, Re number and KC number were varied systematically. The inertia force coefficient (Cu) and the drag force coefficient (CD) in Morison equation were determined from the measured loads and the water particle kinematics. In this analysis a modified form of Morison equation was used since it uses the normal velocity and acceleration. Thus, the applicability of the Cross Flow Principle was assumed. This principle, simply stated, is as follows: the force acting in the direction normal to the axis of a cylinder placed at some oblique angle with the direction of flow is expressed in terms of the normal component of flow only, and the axial component is disregarded. Both the total in-line force coefficient (CF) and transverse force (lift) coefficient (Cf) were analyzed 相似文献
389.
390.
本文介绍了美国R.M.YOUNG公司的新产品-05106型海洋风传感器,并简单地分析了R.M.YOUNG公司在该风传感器中采用的关键技术。 相似文献