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561.
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Oceanology - Abstract—The paper contains original data on the rock-forming and rare element compositions in the Pliocene–Holocene alkaline basaltoids of the Tsushima Basin Sea of Japan,... 相似文献
564.
Gordeev V. V. Dara O. M. Alekseeva T. N. Kochenkova A. I. Boev A. G. Lokhov A. S. Belorukov S. K. 《Oceanology》2020,60(3):384-392
Oceanology - The paper presents the first results of a study of seasonal variations in the grain size distribution and mineral compositions of suspended particulate matter (SPM) of the Northern... 相似文献
565.
A new algorithm for calculating the vertical velocity is suggested. Horizontal current velocity components are expressed through
level inclination and wind/temperature forcing. The acquired relations are given in the difference form, with the accuracy
being sufficiently high. The algorithm is tested using cases where a numerical solution is matched up with an exact one. The
derived data are subsequently analysed.
Translated by Vladimir A. Puchkin. 相似文献
566.
G. T. Csanady 《Journal of Oceanography》1997,53(1):67-80
A “slip law” connects the excess velocity or “slip” of a wind-blown water surface, relative to the motion in the middle of
the mixed layer, to the wind stress, the wind-wave field, and buoyancy flux. An inner layer-outer layer model of the turbulent
shear flow in the mixed layer is appropriate, as for a turbulent boundary layer or Ekman layer over a solid surface, allowing,
however, for turbulent kinetic energy transfer from the air-side via breaking waves, and for Stokes drift. Asymptotic matching
of the velocity distributions in inner and outer portions of the mixed layer yields a slip law of logarithmic form, akin to
the drag law of a turbulent boundary layer. The dominant independent variable is the ratio of water-side roughness length
to mixed layer depth or turbulent Ekman depth. Convection due to surface cooling is also an important influence, reducing
surface slip. Water-side roughness length is a wind-wave property, varying with wind speed similarly to air-side roughness.
Slip velocity is typically 20 times water-side friction velocity or 3% of wind speed, varying within a range of about 2 to
4.5%. A linearized model of turbulent kinetic energy distribution shows much higher values near the surface than in a wall
layer. Nondimensional dissipation peaks at a value of about eight, a short distance below the surface. 相似文献
567.
Automatic Registration of TOBI Side-Scan Sonar and Multi-Beam Bathymetry Images for Improved Data Fusion 总被引:1,自引:0,他引:1
Deep towed side-scan sonar vehicles such as TOBI acquire high quality imagery of the seafloor with very high spatial resolution but poor locational accuracy. Fusion of the side-scan sonar data with bathymetry data from an independent source is often desirable to reduce ambiguity in geological interpretations, to aid in slant-range correction and to enhance seafloor representation. The main obstacle to fusion is accurate registration of the two datasets.The application of hierarchical chamfer matching to the registration of TOBI side-scan sonar images and multi-beam swath bathymetry is described. This matches low level features such as edges in the TOBI image, with corresponding features in a synthetic TOBI image created by simulating the flight of the TOBI vehicle through the bathymetry. The method is completely automatic, relatively fast and robust, and much easier than manual registration. It allows accurate positioning of the TOBI vehicle, enhancing its usefulness as a research tool. The method is illustrated by automatic registration of TOBI and multi-beam bathymetry data from the Mid-Atlantic Ridge. 相似文献
568.
569.
L. Frlin T. Andersson B.-E. Bengtsson J. Hrdig . Larsson 《Marine environmental research》1985,17(2-4)
The present preliminary report on studies of the influence of pulp bleach plant effluents on hepatic biotransformation enzymes in fish is a part of a major characterisation of biochemical and physiological effects of effluents from pulp industries in Sweden. Our studies on the xenobiotic biotransformation enzymes demonstrate, so far, that the pulp effluents have the potential to strongly induce 7-ethoxyresorufin-O-deethylase activity (EROD) in fish liver and that fish living in the receiving water of an effluent from a pulp bleach plant have induced hepatic EROD activities as well as higher hepatic UDP glucuronyltransferase activities than those living in an unpolluted area. It is thus apparent that measures of induction of biotransformation enzymes in fish liver may be a useful approach in monitoring the presence of potential hazardous compounds released from pulp industries. 相似文献
570.
分析表观耗氧量、滴定碱度及总二氧化碳量等资料来研判红海及亚丁湾间之海水交换。结果显示,红海深层水的方解石及霰石饱和度均比亚丁湾和阿拉伯海深层水的饱和度高。红海全水柱之方解石和霰石都处於过饱和状态,亚丁湾和阿拉伯海中各深度之方解石亦呈过饱和状态,但霰石的饱和探度则大约在500m左右。分析深层水之生物体无机碳与有机碳的分解比值,可以发现此地区深层水中,大约有25%的总二氧化碳增加量是由无机碳酸钙溶解而来。 相似文献