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Journal of Ocean University of China 2019年第2期18卷 358-364页

作者： YU Kaiben YU Shengqi LIU Baohua LIU Zhongchen YANG Zhiguo KAN Guangming ZONG Le College of Marine Geo-Sciences Ocean University of China National Deep Sea Center State Oceanic Administration Laboratory for Marine Geology and Environment Pilot National Laboratory for Marine Science and Technology (Qingdao) Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of Oceanography

A method of obtaining bottom backscattering strength by employing an omnidirectional projector and omnidirectional hydrophone is proposed. The backscattering strength is extracted from monostatic backscattering data. The method was adopted in an experiment conducted in the South Yellow Sea of China. The seafloor surface was relatively smooth and covered by a small quantity of shell fragments, as observed through a digital camera system. Sampling data showed that the main component of the sediment at this experimental site was fine sand. In this paper, we detail the calculation method. Preliminary results of backscattering strength as a function of grazing angle(20?–70?) in the frequency range of 6–24 kHz are presented. The measured backscattering strength increased with the grazing angle and changed more rapidly at large grazing angles(60?–70?). A comparison of the data at different frequencies reveals that the measured backscattering strength substantially rises with the increase of acoustic frequency. A fitting curve of Lambert's law against the measured data shows that the backscattering strength deviates from Lambert's law at large grazing angles.

关键词： acoustic scattering bottom backscattering strength fine sand Lambert’s law

A New Multigrid 3D-VAR Optimization Method for bottom Friction Using HF Radar Current Observation

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Journal of Ocean University of China 2019年第6期18卷 1247-1255页

作者： ZHANG Xiaoshuang WU Xinrong LI Wei WANG Bin ZHU Xiande LIU Kexiu SHAO Caixia SUN Chunjian CHAO Guofang ZHANG Tiecheng Key Laboratory of Marine Environmental Information Technology National Marine Data and Information ServiceMinistry of Natural ResourcesTianjin 300171China School of Marine Science and Technology Tianjin UniversityTianjin 300072China National Ocean Technology Center Ministry of Natural ResourcesTianjin 300112China Marine Environment Institute Tianjin 300200China

This paper proposes a new method for data assimilation of the surface radial current observed by High Frequency ground wave radar and optimization of the bottom friction *** this method,the shallow water wave equation is introduced into the cost function of the multigrid three-dimensional variation data assimilation method as the weak constraint term,the surface current and the bottom friction coefficient are defined as the analytical variables,and the high spatiotemporal resolution surface radial flow observed by the high-frequency ground wave radar is used to optimize the surface current and bottom friction *** method can effectively consider the spatiotemporal correlation of radar data and extract multiscale information from surface radial flow data from long waves to short *** the shallow water wave equation into the cost function as a weak constraint condition can adjust both the momentum and mass fields simultaneously to obtain more reasonable analysis *** optimized bottom friction coefficient is introduced into the regional ocean numerical model to carry out numerical *** test results show that the bottom friction coefficient obtained by this method can effectively improve the accuracy of the numerical simulation of sea surface height in the offshore area and reduce the simulation error.

关键词： multigrid 3D-VAR optimization radial current velocity bottom friction

Geochemistry of black shale at the bottom of the Lower Cambrian in Tarim Basin and its significance for lithosphere evolution

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Science China Earth Sciences 2003年第5期46卷 498-507页

作者：于炳松陈建强李兴武林畅松 SchoolofEarthSciencesandResources ChinaUniversityofGeosciences DepartmentofEnergyandResources ChinaUniversityofGeosciences

The systematic analyses of trace elements, REEs and PGEs of black shale at the bot-tom of the Lower Cambrian in Tarim Basin have been made for the first time in this work. The basic geochemical features are that some trace elements having something to do with the deep-level fluids are highly enriched, including V, Cr, Ni, Cu, Zn, Ge, As, Sr, Y, Mo, Ag, Cd, Sb, Ba, Pb and U, and the Th/U and Th/Sc ratios decreased compared with those in the same kind of rocks in the crust, that the enriched degrees of LREEs are reduced, Eu and Ce depleted distinctly in the chon-drite-normalized REE patterns, and that the contents of PGEs and Au are increased. These char-acteristics indicate that there were more mafic interior sources in the basin when the black shale was deposited. Generally, the interior sources show an extensional tectonic setting of lithosphere. It can be seen from the change of the characteristics of trace elements, REEs and PGEs along the black shale section that the quantity of interior source from inner earth is gradually increased upwards in the lower part of the section, reaches the peak value as shown by sample No. 4 (XCM7-1), and then decreased, which might indicate the episodic extension of lithosphere in the beginning of the Lower Cambrian.

关键词： black shale, geochemistry, bottom of the Lower Cambrian, lithosphere evolution, Tarim Basin.

QUALITY FUNCTION DEPLOYMENT IN bottom-UP PROCESS FOR DESIGN REUSE

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Chinese Journal of Mechanical Engineering 2001年第4期14卷 381-384页

作者： Tan Runhua, Duan Guolin, Liang Yanhong, Yuan Caiyun (School of Mechanical Engineering,Hebei University of Technology) 河北工业大学天津

To deal with a bottom up process model for design reuses a specific extended house of quality(EHOQ)is proposed Two kinds of supported functions,basic supported functions and new supported functions,are *** processes to determine two kinds of functions are presented A kind of EHOQ matrix for a company is given and its management steps are studied.

关键词： Quality function deployment bottom up process Design reuse

Method of coupled mode for long-range bottom reverberation

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Science China(Physics,Mechanics & Astronomy) 2010年第12期53卷 2216-2222页

作者： GAO Bo , YANG ShiE, PIAO ShengChun & HUANG YiWang National Laboratory of Underwater Acoustic Technology,Harbin Engineering University, Harbin 150001, China 1. National Laboratory of Underwater Acoustic Technology Harbin Engineering University Harbin 150001 China

The theory of coupled mode is used for modeling the long-range bottom reverberation in shallow water caused by bottom roughness. The distant bottom reverberation level and spatial coherence of impulsive source are both derived. The results agree with those from the classical reverberation model, and are compared with the experimental data. The influence of source bandwidth and the distance between sources and receivers on the intensity of bottom reverberation are particularly discussed. The method is shown to be available for both the monoand the bi-static cases.

关键词： shallow water couple mode bottom reverberation

The Island Rule with lateral and bottom friction

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Acta Oceanologica Sinica 2019年第4期38卷 146-153页

作者： Yanzhao Yang Zexun Wei Guanlin Wang Zhan Lian Liwei Wang College of Meteorology and Oceanography National University of Defense Technology College of Mathematical Science and Physics Qingdao University of Science and Technology Key Laboratory of Marine Science and Numerical Modeling First Institute of OceanographyMinistry of Natural Resources Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology (Qingdao)

The Island Rule, derived from the Sverdrup theory, is widely used to estimate and analyze water transport through a strait. Previous studies presented single-or multi-island rules with either lateral or bottom friction. In this paper,an analytical model of wind-driven circulation is assumed based on linear dynamics. Considering both lateral and bottom friction, the analytic solutions of the transport streamfunction around the islands are derived and the volume transport through the channel is presented. The results are similar to those of Wajsowicz, but the frictional constants represent different values. The analytic solution shows that the relationship between the lateral frictional and bottom frictional dissipation is complex in terms of the frictional constants. To understand the interaction between the two friction types, lateral and bottom friction values were randomly chosen on a barotropic beta plane. The result shows an approximately linear relationship between the lateral and bottom friction in consisting of the combined frictional constants. We studied the effect of the channel width on the transport through the channel. The results show that the friction enhances the flow under some widths, which is similar to the flow behavior when only the lateral friction is considered. We also compared the transport through the channel at different depths and founded that the deeper the water, the smaller the transport reduction ratio when the horizontal eddy viscosity coefficient and the bottom drag coefficient remained constants. To further present the combined role of lateral frictional and bottom frictional dissipation, we compared our model with the model of Wajsowicz for two islands, where only the lateral or bottom friction were considered, with different channel widths. The results showed that the effect of the lateral friction is greater than the bottom friction when the channel is narrow, especially in the Munk boundary layer thickness. When the channel is

关键词： Island Rule lateral friction bottom friction transport streamfunction

Field measurements of bottom boundary layer processes and sediment resuspension in the Changjiang Estuary

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Science China Chemistry 2001年第S1期44卷 80-86页

作者：何青李九发李炎金惜三车越 1. State Key Laboratory of Estuarine & Coastal Research East China Normal University 200062 Shanghai China2. Second Institute of Oceanography State Oceanic Administration 310012 Hangzhou China

A field observation of the hydrodynamics and the sediment resuspension in a bottom boundary layer was carried out in the Changjiang Estuary, during July-August 1997. Using bottom field research facilities, detailed measurements of near-bottom currents and suspended sediment concentration distribution within 1.0 m above bed have been obtained in the Changjiang Estuary-a high concentration estuary. An Acoustic Suspended Sediment Monitor (ASSM) wasused to observe near bed sediment resuspension processes. In addition, the log-profile method was applied to estimating hydraulic roughness 2b and bottom shear stress values (or friction velocities u). Further understanding of sediment suspension mechanics and hydrodynamic characteristics will require the long-term measurements of near bed processes.

关键词： bottom boundary layer sediment resuspension roughness shear stress Changjiang Estuary.

Deep water bottom current deposition in the northern South China Sea

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Science China Earth Sciences 2007年第7期50卷 1060-1066页

作者： SHAO Lei LI XueJie GENG JianHua PANG Xiong LEI YongChang QIAO PeiJun WANG LiaoLiang WANG HongBin State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Guangzhou Marine Geological Survey Ministry of Land and ResourcesGuangzhou 510075China CNOOC Ltd.Shenzhen Shenzhen 518067China

There are some active bottom currents on the northern continental slope of the South China Sea (SCS). Reflection seismic profiles show that the bottom current channels occur in the water depth range of 1000 to 2700 m,extending from the NE to the SW,leading to accumulation of discontinuous drifts with higher sedimentation rates on the eastern side of the channel. The stacking pattern of the layers sug-gests that these drifts propagated southwestward,following the direction of the bottom currents. One sedimentary drift to the southeast of the Dongsha Islands has the highest sedimentation rate of 97cm/ka in the last 12 ka. The sedimentary characteristics of the sediment layers indicate that these bottom currents are most likley caused by the water movement of a branch of the West Pacific Ocean Current,which enters the northern SCS via the Bashi Strait. Once formed,the bottom currents trans-port sediments along the northern slope of SCS southwestward and finally disappear into the central basin of the SCS. Due to the bottom current activity,the deep-sea sedimentary process in the northern SCS is complex.

关键词： deep water bottom current deep sea deposition sedimentary drift reflection seismic profile South China Sea

TROPICAL CYCLONE GENESIS EFFICIENCY:MID-LEVEL VERSUS bottom VORTEX

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Journal of Tropical Meteorology 2013年第3期19卷 197-213页

作者：葛旭阳李天明彭顺台 Department of Meteorology and International Pacific Research Center University of Hawaii Naval Research Laboratory MontereyUSA

Cloud resolving Weather Research and Forecasting(WRF)model simulations are used to investigate tropical cyclone(TC)genesis efficiency in an environment with a near bottom vortex(EBV)and an environment with a mid-level vortex(EMV).Sensitivity experiments show that the genesis timing depends greatly on initial vorticity vertical *** larger the initial column integrated absolute vorticity,the greater the genesis efficiency *** the same column integrated absolute vorticity,a bottom vortex has higher genesis efficiency than a mid-level vortex.A common feature among these experiments is the formation of a mid-level vorticity maximum prior to TC genesis irrespective where the initial vorticity maximum *** the EMV and EBV scenarios share the following development characteristics:1)a transition from non-organized cumulus-scale(~5 km)convective cells into an organized meso-vortex-scale(~50 to 100 km)system through upscale cascade processes,2)the establishment of a nearly saturated air column prior to a rapid drop of the central minimum pressure,and 3)a multiple convective-stratiform phase transition.A genesis efficiency index(GEI)is formulated that includes the following factors:initial column integrated absolute vorticity,vorticity at top of the boundary layer and vertically integrated relative *** calculated GEI reflects well the simulated genesis efficiency and thus may be used to estimate how fast a tropical disturbance develops into a TC.

关键词： tropical cyclone genesis mid-level vortex near bottom vortex genesis efficiency cyclogenesis time

STUDY ON bottom STRESS UNDER CONDITIONS OF STORM SURGE AND TIDE

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Chinese Journal of Oceanology and Limnology 1994年第2期12卷 144-153页

作者：汪景庸虞旭日 1. Ocean University of Qingdao 266003 Qingdao China

Sea bottom stress is conventionally assumed to be directly proportional to the square of the verticallyaveraged velocity,and the drag coefficient to be dependent on the speed and direction of the wind on the sea surface,the depth and dimension of the sea,the period of the tide and so on. In this paper a three-dimensional numerical model is used to discuss the relation the dragcoefficient and the above-mentioned *** can be shown from calculation that the relation, is valid,that the drag coefficient is a constant in a major part of a sea as thought conventionally,andthat there is a small area near the coast where the drag coefficient is far *** call it singular area. A number of conclusions on the relation between the drag coefficient and the speed and direction ofthe wind,the sea depth and so on,were obtained.

关键词： bottom stress storm surge tide