Theoretical wind wave frequency spectra in deep water——Ⅰ. Form of spectrum   总被引：1，自引：0，他引：1  

Wen Shengchang 《海洋学报(英文版)》1988,7(1):1-16

In this part ot the paper theoretical wind-wave spectra nave been derived oy (I) expressing the spectrum in series composed of exponential terms; (2) assuming that the spectrum satisfies a high order linear ordinary differential equation; (3) introducing proper parameters in the spectrum; and (4) making use of some known charateristics of wind-wave spectrum, for instance, the law governing the equilibrium range. The spectrum obtained contains the zero order moment of the spectrum m0, the peak frequency ω0 and the ratio R =ω/ω0 (ω being the mean zero-crossing frequency) as parameters. The shape of the nondimensional spectrum S(ω) = ω0S(ω)/m0(ω=ω/ω0) changes with R and theoretically reduces to a Dirac delta function δ(ω-1) when R = 1. A spectrum of simplified form is given for practical uses, in which R is replaced by a peakness factor P=S(1).  相似文献   

Dynamics of subtidal flow in the Taiwan Strait   总被引：7，自引：0，他引：7  

Wen -Ssn Chuang 《Journal of Oceanography》1985,41(2):65-72

Two current meter moorings were deployed in the Taiwan Strait from 3 April to 5 May 1983. The data indicate that the subtidal flow in this rather wide strait can be separated into two parts: the mean flow and wind-driven flow, which make about equal contributions to the overall flow. The mean flow is probably originates from branching of the Kuroshio through Bashi Channel. The magnitude of the current is nearly 30 cm sec^–1 flowing northward, and the corresponding along-strait sea surface slope is on the order of 10^–7. The residual flow is a local wind-driven flow, and reaches a frictionally balanced state in about 4 hr. Assuming a linear drag law for the bottom stress, a hindcast scheme is constructed and the results compare well with the observations.  相似文献   

An ecological study on the fouling organisms in Yantai Harbour     

Li Chuanyan  Huang Zongguo  Wang Jianjun  Zheng Chengxing  Lin Sheng 《海洋学报(英文版)》1991,10(4):629-633

Yantai Harbour (37°33′15″N , 121°23′42″E) is situated at the north coast of Shandong Peninsula and is a large fishing and commercial port of North China. From June 1983 to May 1984, a yearly panel test on fouling organisms was carried out at the non-fixed jetties in the inner and outer harbour. The test method was according to "the Marine Survey  相似文献   

伶仃洋L＿2和L＿（16）孔第四纪有孔虫群与孢粉化石带特征及其地质意义   总被引：5，自引：0，他引：5  

陈木宏  赵焕庭  温孝胜  张乔民  宋朝景 《海洋地质与第四纪地质》1994,(1)

本文所依据的分析样品是取自珠江最大的一个河口湾伶仃洋中部的水下钻孔岩芯，其底部到达花岗岩基底。通过对第四纪有孔虫群与孢粉化石带特征的分析，阐明在相同的钻孔岩芯中，有孔虫分布变化所反映的古沉积环境特征与孢粉分析的古气候特征较为吻合，并与相应的沉积相对应，结合￣（１４）Ｃ和￣（２３０）Ｔｈ／￣（２３２）Ｔｈ比值法测年数据，从而较好地重塑本区晚更新世中期以来的地质历史。  相似文献   

海岸工程中海浪数值模拟和环境参数选取的进展     

黄培基 《海岸工程》1995,14(4):1-4

主要介绍了我国近的来在海岸工程设计，建设中有关海浪数值模拟及环境参数选取方面的研究进展。  相似文献   

赤潮发生机理研究──海洋原甲藻的氮营养生理特征   总被引：17，自引：1，他引：17  

黄晓航  史冬梅  张京浦  刘海航  吴超元 《海洋与湖沼》1997,28(1):33-38

于１９９１年１月－１９９１年１２月，以不同浓度的硝态氮（２０，６０，２００，６００μｍｏｌ／Ｌ）研究对赤潮生物海洋原甲藻的生长和生化组成的影响，及其营养生理特性，结果表明，在氮浓度为２００和６００μｍｏｌ／Ｌ时，表现光合作用强，细胞生长快，指数生长期长，叶绿素含量高，提示了由原甲藻爆发引起的赤潮与海洋富营养化有直接关系，结果还表明，海洋原甲藻可以累积蛋白质和碳水化合物，当外界氮源不能满足生长需要时  相似文献   

冲绳海槽西北侧表层沉积物中微型腹足类的分布及其研究意义     

冯伟民  黄宝玉 《海洋科学集刊》1997,(39):123-133

冲绳海槽西北侧大陆架向大陆坡转折处表层沉积物中微型腹足类动物群具有混合的生态特征,这与现代海洋沉积环境并不一致。腹足类动物群中除少数种类为陆坡深海分子,多数种类属内陆架区或近岸浅水分子。因此,动物群主要反映了晚更新世末次冰期低海平面的海洋环境,而少数深海种类的混入应与黑潮暖流在冲绳北端所形成的上升流有关。根据本区腹足类在其他海区的时空分布规律,本文认为在更新世末次冰期,黑潮暖流仍对本区有重要影响，并控制着腹足类的分布。本区腹足类这种混合的生态特征是晚更新世末次冰期以来各种海洋动力环境叠加影响的结果。  相似文献   

青岛沿海佳美羽螅(Aglaophenia whiteleggei Bale)的新记录     

黄美君 《中国海洋大学学报(自然科学版)》1988,(2)

本文首次报报道了在青岛海采集的水螅虫类、羽螅科的一种新记录 佳美羽螅(Aglaophenia whiteleggei Bale)并将这种羽螅和1927年Hargitt根据厦门标本建立、而后又由林绍文报导的采自舟山群岛嵊山的多荚羽螅(Lytocarpus ruttingi Hargitt)作比较,发现它们在形态特征上完全相同,应该认为多荚羽螅是佳美羽螅的同物异名  相似文献   

Acoustic plane-wave scattering from a rough surface over a random fluid medium     

Jin-Yuan Liu  Chen-Fen Huang  Ping-Chang Hsueh 《Ocean Engineering》2002,29(8):915-930

Acoustic plane-wave scattering from a rough surface overlying a fluid half-space with a sound-speed distribution subject to a small random variation is considered. Under the assumption that the surface roughness and medium randomness are statistically independent, the scattered field may be derived by first solving for the mean field in the medium, and then incorporating with boundary-perturbation method to obtain the total mean field and the power spectral density of the scattered field. The employed algorithm is compatible to the analysis available in the existing literature so that the formulations are conveniently integrated. The results for the power spectral density have shown that the effects of medium inhomogeneities on the rough surface scattering are limited in a spectral regime where the scattered components have shallow grazing angles. The distribution of the power spectral density over the space is primarily governed by the power spectrum and correlation lengths of the rough surface.  相似文献   

非常规管节点疲劳寿命分析与计算   总被引：6，自引：1，他引：6  

谭开忍肖熙  黄小平 《海洋工程》2005,23(3):51-54,59

对非常规管节点的疲劳寿命进行了分析研究，用SESAM计算疲劳载荷，应用精细有限元分析计算热点应力，用规范的S—N曲线计算管节点的疲劳寿命。通过实例计算表明，这些处理对非常规管节点疲劳寿命分析与计算是很有效的。  相似文献