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971.
Zhang Yonggang Li Yucheng Teng Bin
Doctor Degree Candidate The National Key Laboratory of Coastal Offshore Engineering Dalian University of Technology Dalian
Professor The National Key Laboratory of Coastal Offshore Engineering Dalian University of Technology Dalian
Associate Professor The National Key Laboratory of Coastal Offshore Engineering Dalian University of Technology Dalian 《中国海洋工程》1995,(4)
The mild-slope equation derived by Berkhoff (1972), has widely been used in the numerical calculation of refraction and diffraction of regular waves. However, it is well known that the random sea waves has a significant effect in the refraction and diffraction problems. In this paper, a new form of time-dependent mild slope equation for irregular waves was derived with Fade approximation and Kubo's time series concept. The equation was simplified using WKB method, and simple and practical irregular mild slope equation was obtained. Results of numerical calculations are compared with those of laboratory experiments. 相似文献
972.
The circulation in the southern Huanghai Sea and northern East China Sea in June 1999 总被引:1,自引:0,他引:1
Yaochu Yuan Yonggang Liu Mingyu Zhou Arata Kaneko Zhou Yuan Noriaki Gohda 《海洋学报(英文版)》2003,22(3):321-332
On the basis of hydrographic data and current measurement (the mooring system, vessel-mounted ADCP and toward ADCP) data obtained in June 1999, the circulations in the southern Huang-hai Sea (HS) and northern East China Sea (ECS) are computed by using the modified inverse method. The Kuroshio flows northeastward through eastern part of the investigated region and has the main core at Section PN, a northward flow at the easternmost part of Section PN, a weaker anti-cyclonic eddy between these two northward flows, and a weak cyclonic eddy at the western part of Section PN. The above current structure is one type of the current structures at Section PN in ECS. The net northward volume transport (VT) of the Kuroshio and the offshore branch of Taiwan Warm Current (TWCOB) through Section PN is about 26.2×106m3/s in June 1999. The VT of the inshore branch of Taiwan Warm Current (TWCIB) through the investigated region is about 0.4×106m3/s. The Taiwan Warm Current (TWC) has much effect on the currents over the 相似文献
973.
974.
Xiaohong Bai Wubin He Jungang Jia Yunshan Han 《Marine Georesources & Geotechnology》2006,24(3):173-182
Static load tests on pile group with prototype size were carried out in order to study the behavior and the working properties of the cap—pile group—soil interaction in the pile group foundation. The soil resistance under the cap, the pile shaft resistance and the tip resistance were measured by installing various measuring gauges. Based on these test results, the cap—pile group—soil interaction characteristics were analyzed. The regulations of the soil reaction on the cap, the shaft resistance and the tip resistance of pile, the mechanism of load transfer have been discussed with comparison to the result of the single pile tests. The bearing capacity of pile group is greater than the sum of the bearing capacity of the single pile obtained from testing in the same site in pile group foundation in the case presented here. 相似文献
975.
Distribution and sources of organic carbon, nitrogen and their isotopes in sediments of the subtropical Pearl River estuary and adjacent shelf, Southern China 总被引:17,自引:1,他引:17
The isotopic composition (δ13C and δ15N) and organic carbon (OC) and total nitrogen (TN, organic plus inorganic) content of 37 carbonate-free surficial sediments of the subtropical Pearl River estuary and the adjacent shelf of South China Sea (SCS) was determined. The δ13C values indicate that the sediment organic material is a mixture from two sources, terrestrial and marine. Several of the sediments have extremely low (< 4) OC / TN ratios, which could be due to low OC contents and/or to a significant fraction of the TN present as inorganic nitrogen adsorbed on clays. In general, the spatial patterns of OC, TN, δ13C and δ15N are similar. Values are low at the river mouth and on the western coast, suggesting proportionally greater accumulation of terrestrial particulate organic matter relative to marine phytodetritus, which is limited by low productivity in the turbid plume of the Pearl River. Algal-derived organic carbon (al-OC) content is estimated to be low (≤ 0.06%) at the river mouth and higher (up to 0.57%) on the adjacent inner shelf based on a mixing model of end members. 相似文献
976.
海缆安全影响因素评述 总被引:8,自引:2,他引:8
通过对国内外威胁海缆安全因素的研究资料和研究成果的分析,全面论述了影响海缆安全因素的种类及其对海缆的可能破坏方式和破坏的严重程度。简要说明了不同因素对海缆威胁的可能原因与相应的预防措施,为海缆安全运营提供科学的理论依据。 相似文献
977.
罗非鱼球状囊微音器电位是一个双峰波。峰频与刺激声频成2:1关系;在20-80Hz电位波形不规则。在300-900Hz电位波呈矩形。实验表明,球状囊不同区域对一一的声频敏感性不一样;延脑-脊髓连结处的诱发电位与球状囊微音器电位相似,但在130Hz电位呈单峰波;罗非鱼可闻频域在20-900Hz,最大敏感声频在130Hz,其相对敏感性为23.01dB;延脑-脊髓连接处诱发电位最大值在63Hz和130Hz 相似文献
978.
春季南海南部上混合层数值模拟与数值实验 总被引:1,自引:1,他引:1
采用一维湍动能模式对南海南部的 SST及混合层进行数值模拟和数值试验。结果表明 :TKE模式能够模拟南海南部的海表面温度 SST以及除南海南部 5月中旬以外的上混合层深度随时间变化基本特征。在 5~ 6月 ,SST的日振荡主要依赖于短波辐射的日变化 ,风的混合作用抑制了 SST的日周期振荡。春季夏季风爆发期间 ,南海海面潜热通量和感热通量与短波辐射和风应力相比较 ,是一个对 SST和混合层影响较小的量。在春季南海南部 ,短波辐射作用能使 SST升高的最大值约为 4℃ ;潜热和感热通量能使 SST的下降的最大值为 3℃。风应力对南海混合层深度随时间变化趋势起着决定的作用 ,并能使其深度加深 2 0~ 30 m,而短波辐射则使混合层的深度变浅2~ 3m,潜热和感热通量会使混合层的深度加深 1~ 2 m。在春季南海南部 ,热通量对混合层深度的影响与风应力相比要小得多 相似文献
979.
1IntroductionSZ-4spaceborne,launched on30December2002,is the fourth unmanned spaceborne of China.Multimode microwave remote sensor is its primaryload,of which the altimeter mode is the most impor-tant one.During about five months,a large numberofSZ-4altim… 相似文献
980.
岩藻聚糖硫酸酯低聚糖降压作用的初步研究 总被引:8,自引:0,他引:8
采用两肾—夹型建立肾血管性高血压大鼠模型。探讨岩藻聚糖硫酸酯低聚糖对肾血管性高血压大鼠的血压、呼吸及血浆中血管紧张素Ⅱ(Ang Ⅱ)含量的影响。用GY-6088型多道生理参数分析记录仪和张力传感器测定、记录血压和呼吸;用均相竞争法测定Ang Ⅱ的含量。实验表明,12.5,25,50mg/kg的岩藻聚糖硫酸酯低聚糖均能显著地降低肾血管性高血压大鼠的动脉血压。其中,高剂量(50mg/kg)的降压效果与14mg/kg的卡托普利相当;给药大鼠的呼吸频率随血压的变化呈正相关变化;12.5,25,50mg/kg剂量的岩藻聚糖硫酸酯低聚糖均能降低高血压大鼠血浆中Ang Ⅱ的含量。其中,高剂量(25,50mg/kg)组的Ang Ⅱ水平同卡托普利组(14mg/kg)相当。岩藻聚糖硫酸酯低聚糖对肾血管性高血压大鼠有显著的降压作用,抑制AngⅡ生成可能是其降压机制之一。 相似文献