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1.
Through the examination of 377 samples of the Anthomedusae, eight new species and one new record are described.  相似文献   

2.
Two new species of Naticidae ( Mollusca, Gastropoda) collected from the coast of China are described: Cryptonaitca huanghaien- s/s sp. nov. and Sinum vittatum sp. nov. The morphological characteristics between the new species were described and the related information was provided. The similarities and differences between the new species and related species were also compared and discussed. The new species Cryptonaitca huanghaiensis differed from Cryptonaitca hirasei and Cryptonaitca andoi in outer shape, operculum and radula. The new species Sinum vittatum is similar to Sinumjaponicum (Lischke, 1869), but the shell of the former is flat-elliptical in shape, spire very small, slightly convex. While the latter is flat-globular in shape, apex light brown in color, without a brown band on the body whorl. The comparison results revealed that Cryptonaitca huanghaiensis and Sinum vittatum were two new species from the coast of China. Specimens studied were obtained from collections in the Marine Biological Museum, Chinese Academy of Sciences.  相似文献   

3.
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   

4.
In this paper, the mechanism of the interaction between the breast wall of mound breakwater and waves is expounded, then some new views and the law of variation of horizontal and vertical wave pressure over the breast wall are put forward. The results of this study have been adopted in the Specifications of Fishery Harbour Breakwater by the Ministry of Agricultures.  相似文献   

5.
SUN  Hui 《中国海洋工程》2002,16(1):21-32
An eigen-function expansion method based on a new orthogonal inner product is proposed by Sahoo et al. (2000) for the study of the hydroelastic response of mat-type VLFS in head seas. However, their main emphasis is on the effect of edge conditions and they assume that the plate is of a semi-infinite length. In reality, the plate is of finile length. For consider-alion of the finite length effect, the reflection and transmission from the other end must be considered. The effect of this reflection and transmission on the hydroelaslic response of VLFS is of interest for praclical application. Furthermore, the physi-cal meaning of the new inner producl was not given in their paper. In this paper, it is shown that the new inner product can be derived from the governing equation and the bottom boundary conditions. Then the same eigen-function expansion method is adopted for the study of the hydroelastic response of an elastic plate of finite length in surface waves. Delailed comparisons are made between the  相似文献   

6.
The oceans have rich resources of microbes. In recent years, searching for antibiotic of new structure and special biological activity from marine microbes has received great attention. This paper reports the results of the studies on the distribution and the antibacterial properties of Streptomyces in the intertidal zone of Southern Fujian. These studies have important significance to further investigate  相似文献   

7.
A new kind of nematocyst, heteromorphore, and three new types of nematocysts, microbasic spino-mastigophore, microbasic undulata-mastigophore, microbasic laevis-mastigophore, are described from medusae of the Xiamen Harbour and discussed by comparison with the results of other research workers.  相似文献   

8.
- In this paper, the depth of the summer thermocline of the South Huanghai Sea and the East China Sea is calculated with two kinds of one-dimentional models, and the formation reasons are explained for the summer thermocline depth distribution characteristics in the study area. It is proved that in the shelf area of the East China Sea, tidal mixing has an important impact on the thermocline depth. And a new explanation for certain phenomena of the so-called coastal upwelling in the East China Sea is proposed.  相似文献   

9.
Through the examination of 377 samples collected from the Taiwan Straits, two new species of Eirenidae, i. e. , Eirene octonemalis n. sp. and Eutima krampi n. sp. are described. All type specimens are deposited at the Department of Oceanography, Xiamen University.  相似文献   

10.
The new distributions of the statistics of wave groups based on the maximum entropy principle are presented.The maximum entropy distributions appear to be superior to conventional distributions when applied to a limited amount of information.Its applications to the wave group properties show the effectiveness of the maximum entropy distribution.FFT filtering method is employed to obtain the wave envelope fast and efficiently.Comparisons of both the maximum entropy distribution and the distribution of Longuet-Higgins(1984) with the laboratory wind-wave data show that the former gives a better fit  相似文献   

11.
Biochemical mechanism of forming the red tide is discussed in this paper.The existence of a large number of nitrates and phosphates in the eutrophic water is the prerequisite of explosive increase of algae and the forming of red tide.Reduction of eutrophication is an important approach to preventing the red tide.The method of deep treatment of the waste water and its denitrification and dephosphorization are introduced,and a new opinion on the red tide formation and fundamental prevention is put forward.  相似文献   

12.
This paper concerns the calculation of the wave trough exceedance probabilities in a nonlinear sea. The calculations have been carried out by incorporating a second order nonlinear wave model into an asymptotic method. This is a new approach for the calculation of the wave trough exceedance probabilities, and, as all of the calculations are performed in the probability domain, avoids the need for long time-domain simulations. The proposed asymptotic method has been applied to calculate the wave trough depth exceedance probabilities of a sea state with the surface elevation data measured at the coast of Yura in the Japan Sea. It is demonstrated that the proposed new method can offer better predictions than the theoretical Rayleigh wave trough depth distribution model. The calculated results by using the proposed new method have been further compared with those obtained by using the Arhan and Plaisted nonlinear distribution model and the Toffoli et al.’s wave trough depth distribution model, and its accuracy has been once again substantiated. The research findings obtained from this study demonstrate that the proposed asymptotic method can be readily utilized in the process of designing various kinds of ocean engineering structures.  相似文献   

13.
The role of surface waves in the ocean mixed layer   总被引:7,自引:6,他引:1  
Previously, most ocean circulation models have overlooked the role of the surface waves. As a result, these models have produced insufficient vertical mixing, with an under - prediction of the ,nixing layer (ML) depth and an over - prediction of the sea surface temperature (SST), particularly during the summer season. As the ocean surface layer determines the lower boundary conditions of the atmosphere, this deficiency has severely limited the performance of the coupled ocean - atmospheric models and hence the climate studies. To overcome this shortcoming, a new parameterization for the wave effects in the ML model that will correct this systematic error of insufficient mixing. The new scheme has enabled the mixing layer to deepen, the surface excessive heating to be corrected, and an excellent agreement with observed global climatologic data. The study indicates that the surface waves are essential for ML formation, and that they are the primer drivers of the upper ocean dynamics; therefore, they are critical for climate studies.  相似文献   

14.
Based on the maximum entropy principle a new probability density function (PDF) f(x) for the surface elevation of nonlinear sea waves, X, is derived through performing a coordinate transform of X and solving a variation problem subject to three constraint conditions of f( x ). Compared with the maximum entropy PDFs presented previously, the new PDF has the following merits: (1) it has four parameters to be determined and hence can give more refined fit to observed data and has wider suitability for nonlinear waves in different conditions; (2) these parameters are expressed in terms of distribution moments of X in a relatively simple form and hence are easy to be determined from observed data; (3) the PDF is free of the restriction of weak nonlinearity and possible to be used for sea waves in complicated conditions, such as those in shallow waters with complicated topography; and (4) the PDF is simple in form and hence convenient for theoretical and practical uses. l.aboratory wind-wave experiments have been conducted to test the competence of the new PDF for the surface elevation of nonlinear waves. The experimental results manifest that the new PDF gives somewhat better fit to the laboratory wind-wave data than the well-known Gram-Charlier PDF and beta PDF.  相似文献   

15.
The ZRE is a very complicated estuary with multi-river inlets. The total sum of river discharge in the upstream(away from the tidal influence region) of the Zhujiang River can be easily measured. However, when the total river discharges into the estuary from eight inlets, it is a very difficult task to obtain a continuous river discharge flux data from each branch of the Zhujiang River. However, the different ratios of river discharges between the river branches can significantly affect the estuarine circulation feature and baroclinic process. Moreover, the accuracy of numerical forecast for the estuarine circulation is very much dependent on the accuracy of the time history of the river discharge flux for each branch. Therefore, it is important to estimate river discharge from each branch in order to improve the accuracy of the model forecast for the circulation of the ZRE. The development of a new estimation method of the river discharges is focused on based on the system identification theory, numerical modeling and the time history data from the CODAR observed sea surface current. The new approach has been appfied to estimating the time history (hourly) of river discharge from each branch in the upstream of the ZRE.  相似文献   

16.
In order to achieve the complex dynamic analysis of the self-propelled seafloor pilot miner moving on the seafloor of extremely cohesive soft soil and further to make it possible to integrate the miner system with some subsystems to form the complete integrated deep ocean mining pilot system and perform dynamic analysis,a new method for the dynamic modeling and analysis of the miner is proposed and developed in this paper,resulting in a simplified 3D single-body vehicle model with three translational and three rotational degrees of freedom,while the track-terrain interaction model is built by partitioning the track-terrain interface into discrete elements with parameterized force elements built on the theory of terramechanics acting on each discrete element.To evaluate and verify the correctness and effectiveness of this new modeling and analysis method,typical comparative studies with regard to computational efficiency and solution accuracy are carried out between the traditional modeling method of building the tracked vehicle as a multi-body model and the new modeling method.In full consideration of the particular structure design of the pilot miner,the special characteristics of the seafloor soil and the hydrodynamic force of near-seafloor current,the dynamic simulation analysis of the miner is performed and discussed,which can provide useful guidance and reference for the practical miner system in design and operation.This new method can not only realize the rapid dynamic simulation analysis of the miner but also make possible the integration and rapid dynamic analysis of the complete integrated deep ocean mining pilot system in further researches.  相似文献   

17.
Spar technology has been applied to the deep-sea oil and gas exploitation for several years.From the first generation of classic spar,the spar platform has developed into the second generation of truss spar and the latest cell spar.Owing to its favorable adaptability to wide range of water depth and benign motion performances,spar has aroused quite a lot of interests from oil companies,universities and research institutes.In the present paper,a new cell-truss spar concept,put forward by the State Key Laboratory of Ocean Engineering(SKLOE)at Shanghai Jiao Tong University,is studied both numerically and experimentally.The numerical simulation was conducted by means of nonlinear time-domain fully coupled analysis,and its results were compared to the experimental data.Whereafter,detailed analysis was carried out to obtain the global performances of the new spar concept.Proposals for the improvement of numerical calculation and experimental technique were tabled meanwhile.  相似文献   

18.
- In order to verify the theoretical design and computation of a new type of platform, laboratory model test of the superficial sliding of the platform is carried out. Test results show that the requirement for the stability of the platform can be satisfied, and the API-82 criterion can be met. It is also suggested that, in order to enhance the stability of the platform, a buried- pad with porous holes and a long apron-board should be adopted in the design of the new type of platform.  相似文献   

19.
Based on the Bohai ocean environment characteristics, a new platform vibration distribution structure is designed to reduce the platform vibration due to flowing ice. The effect of the earthquake wave and ocean wave load on this vibration distribution structure is considered in the design. The principal idea of this new vibration distribution structure is dividing the platform main column into the inner tube and the outer tube. The outer tube is connected with the leg pontoon by braces, while the inner tube is used to support the platform deck. The inner tube and outer tube can be connected or disconneted in the region near the water line. For evaluating the vibration reduction effect of such a structure, tests are carried out on a steel model, and the external load of flowing ice, earthquake wave and ocean wave are simulated by concentated random load applied to different points of the model. The tests are performed in water media and air media respectively. The vibration reduction effect is evaluated  相似文献   

20.
Articulated buoys become more and more popular by the marine management departments as a new type of aids to navigation, for they possess an excellent hydrodynamic performance with small static heel angle in wind and current and small rolling in wave and accurate position. The structure of articulated buoys and calculation method of their hydrodynamic performance are introduced in this paper. A scries of experiments has been conducted in the State Key Laboratory of Ocean Engineering of China and useful results achieved for providing a design optimization basis.  相似文献   

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