悬浮沙激光散斑图像处理的研究     

杜军兰  陈靖齐  于连生  刘海坤  徐雷 《海洋技术学报》2001,20(1):107-111

本文以统计模式识别为基础，阐述了图像处理在悬浮沙粒粒径流量中的实际应用，提出了用图像层析来确定放大系数的方法，提出了测量的准确度。  相似文献   

大窑湾疏浚物倾倒区环境调查研究   总被引：2，自引：1，他引：2  

邵秘华  杨庆霄 《海洋湖沼通报》1991,(3):19-26

本文以1989年8月调查资料为基础,论述了大窑湾疏浚物倾倒区的水化学要素(pH、盐度、DO、COD、浊度)、营养盐(NO_2-N、NO_3-N、NH_4-N、PO_4-P、SiO_3-Si)和重金属(Cu、Zn、Pb、Cd)等污染物分布特征;分析了水质、底质的环境状况及潮流的影响。从环境地球化学观点探讨了该疏浚物倾倒区选择的科学性。  相似文献   

悬对沙Mellor-Yamada海洋边界层模型计算结果的影响     

李华军  梁丙臣  李东永  李磊岩 《海洋科学》2004,28(1):27-32

为了分析海洋水体垂向水流紊动及紊动交换情况而采用了一维的海洋边界层模型(Mellor-Yamada)并利用数值实验的方法对悬沙、盐度、温度等数据进行分析。原模型未将悬沙考虑在内，本文试将它引入进去探讨由于它的存在对紊动混合特性的影响。2000年4月，Mellor将最初的模型引入了依赖于Richardson数的紊动动能耗散率。本文通过比较具有悬沙和不具有悬沙两种情况下的速度、温度和盐度垂向分布随时间的变化，分析讨论由于悬沙的存在所引发的密度层化对紊动混合作用的影响，并发现悬浮泥沙抑制了部分模拟时间的紊动混合作用。  相似文献   

杭州湾海域水体悬沙粒度统计分析     

茹荣忠 《海洋学研究》2002,20(4):13-18

利用2000年9月在杭州湾进行的原型水文泥沙测验所获取的648个悬沙粒度样品,进行了样品粒度统计分析,结果表明:在杭州湾测验区域,粒径为4.00～20.20μm的悬沙出现频率最高;悬沙的中值粒径值自东向西迅速增大;北岸海域悬沙的中值粒径值大于南岸海域悬沙的中值粒径值。  相似文献   

廉州湾南部海域泥沙来源及运移趋势分析     

谷东起  吴桑云 《海洋科学进展》2001,19(1):25-31

重矿物组合、含量变化和特征矿物的分布及变化规律是沿海泥沙来源和运移趋势判断的重要手段之一。通过对廉州湾南部海域海底表层沉积物的重矿物分析 ,发现该区重矿物分布以北海地角为界 ,其百分含量和特征矿物南北有别 ,可能分别代表不同的物质来源区。其中廉州湾北部南流江流域来沙是该区主要物源 ,运移趋势为自 NE向 SW;地角西南岸段、岭南侧海岸侵蚀及银滩来沙也为该区提供了部分物源 ,运移趋势为绕过冠头岭沿海岸向 N方向运移。由于缺乏北海陆域陆相地层重矿物含量等相关资料 ,暂未做物质来源区的具体判断  相似文献   

藻类功能食品的物质基础与研究开发现状   总被引：3，自引：0，他引：3  

周德庆  管华诗 《中国海洋大学学报(自然科学版)》1995,(Z1)

对藻类功能食品的研究和开发现状作综述报道。涉及的主要内容有：作为功能食品物质基础的食物纤维、ＰＵＦＡ、维生素、矿物质和微量元素、氨基酸以及其它有生理活性的物质。  相似文献   

Two-Dimensional Mathematical Model of Tidal Current and Sediment for Oujiang Estnary and Wenzhou Bay   总被引：1，自引：0，他引：1  

LU  Yongjun 《中国海洋工程》2002,16(1):107-122

A 2-D mathematical model of tidal current and sediment has been developed for the Oujiang Estuary and the WenzhouBay. This model accomodates complicated features including multiple islands, existence of turbidity, and significant differ-ence in size distribution of bed material. The governing equations for non-uniform suspended load and bed load transport arepresented in a boundary-fitted orthogonal curvilinear coordinate system. The numerical solution procedures along with theirinitial conditions, boundary conditions, and movable boundary technique are presented. Strategies for computation of thecritical condition of deposition or erosion, sediment transport capacity, non-uniform bed load discharge, etc. are suggested.The model verification computation shows that, the tidal levels computed from the model are in good agreement with the fielddata at the 18 tidal gauge stations. The computed velocities and flow directions also agree well with the values measuredalong the totally 52 synchronously observed verticals distributed over 8 cross sections. The computed tidal water throughputsthrough the Huangda‘ao cross section are close to the measured data. And the computed values of bed deformation fromYangfushan to the estuary outfall and in the outer-sea area are in good agreement with the data observed from 1986 to 1992.The changes of tidal volumes through the estuary, velocities in different channels and the bed form due to the influence of thereclamation project on the Wenzhou shoal are predicted by means of this model.  相似文献   

Eddy Diffusion Coefficients of Suspended Particulate Matter: Effects of Wind Energy Transfer and Stratification     

Lars Chresten Lund-Hansen  Morten Pejrup  Jens Valeur  Anders Jensen 《Estuarine, Coastal and Shelf Science》1994,38(6)

Gross sedimentation rates (GSR) have been measured using sediment traps placed at nine different levels above the bed (0·3, 0·5, 0·8, 1·0, 2·0, 4·0, 6·0, 8·0 and 10·0 m). The sediment traps were deployed for 1·25 years and recovered 28 times during the study period. Low average GSR values of 5·5 g m^-2 day^-1 were obtained at 10·0 m, and high average GSR values of 114·8 g m^-2 day^-1 were obtained at 0·3 m. An expression for the eddy diffusion coefficient of suspended particulate matter (K_s), based on the measured GSR is given. The expression has been used for modelling of K_s at the different trap levels above the bed. High values (≈42 cm² s^-1) of K_s were obtained at the upper traps, whereas low values (≈2 cm² s^-1) were obtained near the bed. Comparison between level of turbulent energy in terms of shear stress at the boundaries of the water column, i.e. from the wind and the bed flow, showed that wind energy exceeded that of the bed flow by a factor 16. At 5·0 m K_s was positively correlated (r=0·66) to the eddy diffusion coefficient of momentum (K_m) derived from the wind energy transfer to the water, giving an average β of 0·5 for K_s =βK_m. The density difference between surface and bottom waters has been designated a parameter of stratification, and is discussed in relation to variations of K_s and K_m .  相似文献   

Field Placement and Evaluation of Stabilized Dredged Material (SDM) from the New York/New Jersey Harbor     

A. Maher  W. S. Douglas  F. Jafari 《Marine Georesources & Geotechnology》2006,24(4):251-263

Since the 1997 local ban on ocean dumping of dredged sediments, the States of New York and New Jersey have pursued a policy of environmentally sound solutions to the management of dredged material, including beneficial use of stabilized dredged material (SDM) in transportation applications. A pilot study was initiated in 1998 to evaluate the use of SDM in the construction of highway embankments. Utilizing 80,000 cubic yards of dredged material, two embankments were constructed from SDM on a commercial development area adjacent to the Harbor. Geotechnical properties and handling of SDM were evaluated both during and one year post - construction. This article presents the evaluation of the embankments themselves, including constructability and performance. The results demonstrate that SDM satisfies most of the geotechnical criteria for fill construction, except those for durability, requiring proper coverage and protection similar to that provided for fills constructed on cohesive soils. This same characteristic precludes long term stockpiling of SDM prior to final placement, limiting applications to those that have schedules overlapping with dredging projects. Increased costs for the use of SDM can be as high as $8 per cubic yard over traditional fills; however, this cost may be recouped through management fees collected from dredging projects.  相似文献   

Atmospheric Correction of SeaWiFS Data for the Retrieval of Suspended Sediment in East China Coastal Waters     

廖迎娣  张玮P．Y．Deschamps 《中国海洋工程》2005,19(2):225-234

The data of SeaWiFS (Sea-Viewing Wide Field-of-View Sensor), installed on SeaStar, has been used to generate SSC (suspended sediment concentration) of complex and turbid coastal waters in China. In view of the problems of the SeaDAS (SeaWiFS Data Analysis System) algorithm applied to China coastal waters, a new atmospheric correction algorithm is discussed, developed, and used for the SSC of East China coastal waters. The advantages of the new algorithm are described through the comparison of the restdts from different algorithms.  相似文献