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151.
The Kuroshio East of Taiwan and in the East China Sea and the currents East of Ryukyu Islands during early summer of 1996 总被引:6,自引:0,他引:6
Yaochu Yuan Arata Kaneko Jilan Su Xiaohua Zhu Yonggang Liu Noriaki Gohda Hong Chen 《Journal of Oceanography》1998,54(3):217-226
Using hydrographic data and moored current meter records and the ADCP observed current data during May–June 1996, a modified
inverse method is applied to calculate the Kuroshio east of Taiwan and in the East China Sea and the currents east of Ryukyu
Islands. There are three branches of the Kuroshio east of Taiwan. The Kuroshio in the East China Sea comes from the main (first)
and second branches of the Kuroshio east of Taiwan. The easternmost (third) branch of the Kuroshio flows northeastward to
the region east of Ryukyu Islands. The net northward volume transports of the Kuroshio through Section K2 southeast of Taiwan and Section PN in the East China Sea are 44.4×106 and 27.2×106 m3s−1, respectively. The western boundary current east of Ryukyu Islands comes from the easternmost branch of the Kuroshio east
of Taiwan and an anticyclonic recirculating gyre more east, making volume transports of 10 to 15×106 m3s−1. At about 21°N, 127°E southeast of Taiwan, there is a cold eddy which causes branching of the Kuroshio there. 相似文献
152.
对与我国金属矿产资源探寻有关基础研究的思考和讨论 总被引:1,自引:0,他引:1
在分析国内外对金属矿产资源的需求形势和我国金属矿产资源探明储量状况的基础上,提出了我国金属矿产资源探寻的基础研究目标:在我国现有国力情况下,与金属矿产资源探寻有关基础研究的近期目标是在大规模成矿作用研究基础上,为在我国东部大型矿集区千米级尺度深部发现现实可利用的资源储量提供科学依据和指导;中、长期目标主要是为西部大型矿集区雏形的圈定奠定科学基础,为国家战略性资源接替基地的寻找和确定服务。 相似文献
153.
虚拟内窥镜的研究发展现状 总被引:3,自引:0,他引:3
本文对内窥镜的起源、原理、优点作了一个较为全面的综述,介绍了虚拟内窥镜的技术组成,分析了研究开发虚拟内窥镜技术的难点。然后就目前一些成型的内窥交易产品进行了比较,就虚拟内窥交易技术的发展,应用、市场前景作一展望。 相似文献
154.
The seasonal circulation in the southeastern Huanghai Sea has been studied with hydrographic data,which were observed in February and June 1994 and bimonthly during 1970-1990,and numerical model results.Horiwntal distributions of temperature and salinity in 1994 are quite different due to strong tidal mixing so that we need a analysis to see the real distributions of water masses.The mixing ratio analysis with the data of 1970-1990 shows the connection of the waters in the west coasts of Kotea Peninsula with warm and saline waters from the south in summer,which means northward inflows along the west coasts of Korea Peninsula in summer.With this flow,the seasonal circulations,which are deduced from the seasonal change of water mass distributions in the lower layer,are warm inflows in winter and mld outflows in summer in the central Huanghai Sea,and cold outflows in winter and warm inflows in summer along the west coasts of Korea Peninsula.The seasonally changed inflows might be the Huanghai Sea Warm Current.The monsoon winds can drive such circulations.However,summer monsoon winds are weak and irregular.As one of other possible dynamics,the variation of Kuroshio transport is numerically studied with allowing sea level fluctuations.Although it should be studied more,it possibly drives the summer circulations.The real circulations seem to be driven by both of them. 相似文献
155.
Direct Measurements of Deep Currents in the Northern Japan Sea 总被引:5,自引:0,他引:5
Masaki Takematsu Zentaro Nagano Alexander G. Ostrovski Kuu Kim Yuri Volkov 《Journal of Oceanography》1999,55(2):207-216
Long-term current measurements by means of subsurface moorings were made for the first time at seven sites in the Japan Basin,
the northern part of the Japan Sea. The objective was to directly explore the velocity field in the highly homogeneous deep
water mass (the Japan Sea Proper Water) that occupies depths below 500 m. On each mooring three current meters were equipped
at an approximately equal distance below about 1000 m depth. Duration of the measurements was 1 to 3 years depending on specific
site. This paper describes the basic data set from the moored measurements. It is found that the deep water of the Japan Basin
is very energetic with eddies and vertically coherent currents of the order of 0.1 m/s. Surprisingly, the currents and eddies
exhibit strong seasonal dependence even in the deepest layers of the Basin. The observed new current features are discussed
in comparison with conventional deep circulation pictures derived from hydrographic data.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
156.
Monthly Variations of Water Masses in the Yellow and East China Seas, November 6, 1998 总被引:4,自引:0,他引:4
The monthly water mass variations in the Yellow Sea and the East China Sea are investigated using over 40 years of historical
temperature and salinity observations via a cluster analysis that incorporates geographical distance and depth separation
in addition to the temperature and salinity. Results delineate monthly variations in the major water masses and provide some
insight into formation mechanisms and intermixing. The major water masses include the Kuroshio-East China Sea water (KE),
the Yellow Sea surface water (YSS) and bottom cold water (YSB), mixed water (MW), and coastal water (CW). The distribution
of the KE water mass reveals the intrusion pattern into the area west of Cheju. A separate mixed water type appears between
the KE water mass and the Yellow Sea water masses during winter. The formation mechanism of the YSB appears to be the surface
cooling and active mixing in winter. In the East China Sea, during summer, surface water is differentiated from the subsurface
water while there is no differentiation during winter. In the Yellow Sea, a three layer system exists in the summer and fall
(May–November) while a two layer system exists during the rest of the year. A fresh water mass generated by Yangtze River
discharge (YD) is present over the northern East China Sea and the southern Yellow Sea during summer.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
157.
浮式防波堤充分利用波能在水深方向的分布特性,在满足工程消浪要求的同时对海域水沙交换影响较小,且能够快速布置,在某些实际工程有一定应用前景。为了深入了解波浪作用下浮式防波堤的动力响应,基于OpenFOAM标准求解器olaFlow,在刚体运动求解计算中植入锚链求解模块MOODY(mooring cable dynamics),实现了基于重叠网格方法的浮体运动与锚链受力耦合求解,建立了锚链系泊浮式防波堤动力响应的二维数值模型。利用该数值模型对锚链系泊单方箱浮式防波堤在波浪作用下的透射系数、运动响应、锚链张力进行了模拟,并和相关试验结果进行了比较。结果表明,模型能够准确模拟二维波浪和浮式防波堤的相互作用,并用于三维模型的改进。 相似文献
158.
为研究顺应式海洋平台慢漂运动的影响因素,以截断圆柱和漂浮方箱为例进行了不规则波作用下的慢漂运动模型试验。测量了不同系泊刚度条件下的漂浮方箱以及相同系泊刚度条件下的截断圆柱和漂浮方箱在静水中自由衰减运动和在不规则波中的运动响应,并将运动响应分解成一阶波频运动响应和二阶低频运动响应,分析了系泊刚度和浮体形状对浮体运动的影响。通过物理模型试验发现了系泊刚度及浮体形状对顺应式系泊浮体一阶运动标准差和二阶低频运动平均漂移值和标准差的关系。结果表明由于顺应式浮体的固有周期远离波浪谱峰周期时,系泊刚度以及浮体形状对慢漂运动的一阶运动响应影响不大;二阶低频运动相对偏离平衡位置的平均值和标准差均随系泊刚度增大而减小,浮体形状同样对慢漂运动的二阶低频纵荡运动响应影响较大。试验结果为实际海洋工程的外形选择和系泊刚度选择提供数据支持。 相似文献
159.
160.
Naohisa Nishida Taku Ajioka Ken Ikehara Rei Nakashima Hajime Katayama Tomoyuki Sato Seishiro Furuyama Toru Tamura 《Sedimentology》2020,67(1):559-575
Sandy shelf sediments are important elements of clastic sedimentary systems because of their wide distribution in the geological record and their significance as hydrocarbon reservoirs. Although many studies have investigated shelf sediments influenced by waves or tidal currents, little is known about shelf sediments influenced by oceanic currents, particularly their lithofacies characteristics and stratigraphic evolution. This study investigated the stratigraphic evolution of shelf sediments off the Kujukuri strandplain facing the Pacific Ocean, which is influenced by the strong Kuroshio Current. Sediment cores were obtained from six locations on the Kujukuri shelf (34 to 124 m water depth) using a vibrocorer. The dominant lithofacies is mud-free sand with low-angle cross-lamination associated with alternating beds of finer and coarser sand with cross-lamination. These display depositional processes influenced by storm waves and the Kuroshio Current, respectively. This finding is consistent with the previously presented modern and historical observations of the Kuroshio Current and estimates of the storm-wave base. Radiocarbon dates show that the sediment succession formed during the last transgressive and highstand stages after 13·1 ka. The depositional processes during the stages represent a transition from storm waves with abundant sediment supply to both storm waves and the Kuroshio Current with sediment starvation mainly due to its trapping in the strandplain. Comparison to other Holocene–Modern shelf systems suggests that the sandy shelf successions are strongly influenced by oceanic currents under conditions of limited riverine input and open coastal geometry. The resultant sand-dominated succession is characterized by reversal of the proximal to distal grain-size trend compared to the fining for most other recognized wave/storm-dominated shelf successions. This is because of seaward increase in the influence of the Kuroshio Current. Thus, shelf deposits are naturally complex, and these may be further complicated by the additional influence of oceanic currents above the usual wave-dominated and tide-dominated end members. 相似文献