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791.
792.
The geometry and internal structures of modern sediments on the inner shelf off the southeastern coast of Korea were investigated by means of analysing high-frequency (3.5 kHz) seismic records. The records reveal a wedge-shaped sediment body, tapering off toward the sea. On the basis of reflection patterns, the sediments can be classified into two units; foreset (prodelta) unit and bottomset unit, consisting of sandy muds and clays, respectively. The lateral transition from foreset to bottomset deposits suggests a prograding delta system of the Nakdong River since the late Holocene. 相似文献
793.
Abu Affan Joon-Baek Lee Jun -Teck Kim Young -Chan Choi Jong -Man Kim Jung -Goo Myoung 《Ocean Science Journal》2007,42(2):117-127
The dynamics of phytoplankton abundance with seasonal variation in physicochemical conditions were investigated monthly at
10 stations around the Chagwi-do off the west coast of Jeju Island, Korea, including inshore, middle shore, and offshore in
the marine ranching area from September 2004 to November 2005. Water temperature varied from 12.1 to 28.9°C (average 18.8°C),
and salinity from 28.9 to 34.9 psu (average 33.7 psu). The chlorophyll a concentration was 0.02-2.05 μg L1 (average 0.70 μg L1), and the maximum concentration occurred in the bottom layer in April. A total of 294 phytoplankton species belonging to
10 families was identified: 182 Bacillariophyceae, 52 Dinophyceae, 9 Chlorophyceae, 12 Cryptophyceae, 6 Chrysophyceae, 4 Dictyophyceae,
13 Euglenophyceae, 6 Prymnesiophyceae, 5 Prasinophyceae, and 5 Raphidophyceae. The standing crop was 2.21-48.69x104 cells L1 (average 9.23x 104 cells L1), and the maximum occurred in the bottom layer in April. Diatoms were most abundant throughout the year, followed by dinoflagellates
and phytoflagellates. A phytoplankton bloom occurred twice: once in spring, peaking in April, and once in autumn, peaking
in November. The spring bloom was represented by fourChaetoceros species andSkeletonema costatum; each contributed 10–20% of the total phytoplankton abundance. The autumn bloom comprised dinoflagellates, diatoms, and phytoflagellates,
of which dinoflagellates were predominant.Gymnodinium conicum, Prorocentrum micans, andP. triestinum each contributed over 10% of the total phytoplankton abundance. 相似文献
794.
795.
On the heave radiation of a rectangular structure 总被引:2,自引:0,他引:2
Jaw-Fang Lee 《Ocean Engineering》1995,22(1)
In this paper, an analytic solution to the heave radiation problem of a rectangular structure is presented. To solve the problem analytically, the nonhomogeneous boundary value problem is linearly decomposed into homogeneous ones, which can be readily solved. To provide further comparisons to the present analytic solution, a boundary element method is also presented to solve the problem. The present analytic solution is compared with the result by Black et al. [(1971)] Radiation and scattering of water waves by rigid bodies. J. Fluid Mech. 46, 151–164], and the boundary element solution, and the comparisons show very good agreements. Upon examination of the present analytic solution, it is shown that the solution satisfies the nonhomogeneous boundary condition in a sense of series convergence. Using the present analytic solution, the generated waves, the added mass and the radiation damping coefficients, as well as the hydrodynamic effects of the submergence and the width of the structure, are investigated. 相似文献
796.
Kim IC Chang SY Williams TD Ja Kim Y Yoon YD Lee YS Park EH Lee JS 《Marine environmental research》2004,58(2-5):687-691
We cloned the vitellogenin gene from the self-fertilizing fish Rivulus marmoratus, and sequenced 12,326 bp. The number of exons of R. marmoratus and rainbow trout vitellogenin genes were different, and also the splicing junctions are different throughout most of the exons and introns but the amino acid similarity of R. marmoratus vitellogenin gene to other species was rather high. In promoter region of R. marmoratus vitellogenin gene, there were several E2 binding sites and the estrogen response element (ERE). We discuss here the gene structure and expression of R. marmoratus vitellogenin gene. 相似文献
797.
Isao Kudo Takeshi Yoshimura Choon-Weng Lee Mitsuru Yanada Yoshiaki Maita 《Journal of Oceanography》2007,63(5):791-801
Nutrient regeneration and oxygen consumption after a spring bloom in Funka Bay were studied on monthly survey cruises from
February to November 1998 and from March to December 1999. A high concentration of ammonium (more than 4 μmol l−1) was observed near the bottom (80–90 m) after April. Phosphate and silicate gradually accumulated and dissolved oxygen decreased
in the same layer. Salinity near the bottom did not change until summer, leading to the presumption that the system in this
layer is semi-closed, so regenerated nutrients were preserved until September. Nitrification due to the oxidation of ammonium
to nitrate was observed after June. Nitrite, an intermediate product, was detected at 4–7 μmol L−1 in June and July 1999. Assuming that decomposition is a first order reaction, the rate constant for decomposition of organic
nitrogen was determined to be 0.014 and 0.008 d−1 in 1998 and 1999, respectively. The ammonium oxidation rate increased rapidly when the ambient ammonium concentration exceeded
5 μmol L−1. We also performed a budget calculation for the regeneration process. The total amount of N regenerated in the whole water
column was 287.4 mmol N m−2 in 4 months, which is equal to 22.8 gC m−2, assuming the Redfield C to N ratio. This is 34% of the primary production during the spring bloom and is comparable to the
export production of 25 gC m−2 measured by a sediment trap at 60 m (Miyake et al., 1998). 相似文献
798.
This paper presents a technique to generate waves at oblique angles in finite difference numerical models in a rectangular grid system by using internal generation technique [Lee, C., Suh, K.D., 1998. Internal generation of waves for time-dependent mild-slope equations. Coast. Eng. 34, 35–57.] along an arc-shaped line source. Tests were made for four different types of wave generation layouts. Quantitative experiments were conducted under the following conditions: the propagation of waves on a flat bottom, the refraction and shoaling of waves on a planar slope, and the diffraction of waves to a semi-infinite breakwater. Numerical experiments were conducted using the extended mild-slope equations of Suh et al. [Suh, K.D., Lee, C., Park, W.S., 1997. Time-dependent equations for wave propagation on rapidly varying topography. Coast. Eng. 32, 91–117.]. The fourth layout type consisting of two parallel lines connected to a semicircle showed the best solutions, especially for a small grid size. This technique is useful for the numerical simulation of irregular waves with broad-banded directional spectrum using conventional spectral wave models for the reasonable estimation of bottom friction and wave-breaking. 相似文献
799.
Soon-Sup Lee Jong-Kap Lee Beom-Jin Park Dong-Kon Lee Soo-Young Kim Kyung-Ho Lee 《Ocean Engineering》2006,33(13):1814-1828
In this paper, internet-based ship technical information management system has been developed as a means to accumulate, manage, share and utilize various distributed applications and information used for ship design and building. The information managed in the system is documents from the whole life cycle including concept design, basic design, detailed design, construction, operation and maintenance. In addition, using the developed system, integrated system framework is also proposed to integrate applications and database in concurrent engineering environment. 相似文献
800.
Seungshic Yum Seonock Woo Man Chang Taek-Kyun Lee Jun-Im Song 《Ocean Science Journal》2005,40(1):55-59
We cloned the complete cDNA of the β-tubulin from the soft coral,Scleronephthya gracillimum (Kükenthal) (Alcyonacea, Octocorallia, Anthozoa, Cnidaria), via the random sequencing of a cDNA library and the 5′-rapid
amplification of cDNA end (RACE) technique. The full-length cDNA of theS. gracillimum β-tubulin comprised 1541 bp, not including the poly (A)+ stretch, also contained a complete open reading frame, which codes for a total of 445 amino acids. The amino acid residues
16-402 appeared to be in a state of conservation in a variety of animals. Northern blot analysis clearly demonstrated that
the sequence we have obtained is, indeed, the full-length cDNA of the β-tubulin gene inS. gracillimum. 相似文献