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Progress in Natural Science:Materials International 2007年第3期17卷 289-297页

作者： LIU Zhiyu and WEI Hao (Key Laboratory of Physical oceanography, State Education Ministry, ocean university of {3., qingdao 2.6003. china) Key Laboratory of Physical oceanography Ocean University of China Qingdao 266003 China

High frequency velocity fluctuations were measured by using an acoustic Doppler velocimeter (ADV) in the tidal bottom boundary layer (BBL) of the Yellow Sea (YS) for 25 h. The turbulent kinetic energy dissipation rate and the bottom shear stress were estimated and analyzed. Results show that: (1) in the tidal BBL of the YS, the variations of the dissipation rate and the bottom shear stress during 25 hare (1.8×10-8-3.4×10 -5) W·kg-1 and (6.6×10-4-7.5×10-1) N·m - 2 respectively, indicating that there are strong dissipations in the tidal BBL of the YS; (2) in the well-mixed tidal BBL, the turbulence is mainly shear-induced locally and the production and dissipation are generally in equilibrium; (3. for the seas where the semidiurnal tidal current is dominant, both the dissipation rate and the bottom shear stress exhibit a strong quarter-diurnal variation; (4) the mean bottom drag coefficient Cd (0.45) is 0.0017 (corresponding Cd( 1.00) = 0.0015), but it has significant variations (0.0005-0.0082). The mean bottom roughness length is 2.8×10-5 m.

关键词： tidal bottom boundary layer turbulent kinetic energy dissipation rate bottom shear stress ADV the Yellow Sea.

Boundary-processing-technique in EMD method and Hilbert transform

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Chinese Science Bulletin 2001年第11期46卷 954-961页

作者： DENG Yongjun, WANG Wei, QIAN Chengchun, WANG Zhong & DAI DejunNetwork Center, ocean university of qingdao.{3. Physical oceanography Laboratory, ocean Universily of qingdao,{3. Network Center Ocean University of Qingdao Qingdao China Physical oceanography Laboratory Ocean University of Qingdao Qingdao China

By virtue of neural network, a series of signals is extended forward and backward, as a result, two additional maxima and two additional minima are obtained at both ends of the original data set, with which the EMD decomposition can be exactly achieved with cubic spline interpolation. Meanwhile, by using of neural network every IMF component can also be extended forward and backward, which effectively restrains the end effect, thus the veracious Hilbert spectra are achieved. Verifications of the sample signals and the actual surface elevation of sea waves show that the present extension method is relatively accurate.

关键词： EMD method neural network Hilbert spectrum.

The low frequency oscillations of the sea surface temperature in the Equatorial Eastern Pacific and El Nino formation

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Acta oceanologica Sinica 1989年第4期8卷 521-533页

作者： Zhou Faxiu and Yu Shenyu ocean university of Oingdao, qingdao, {3. ocean Univ. of qingdao Qingdao China. China

-In this paper the variations of the sea surface temperature anomalies (SSTA) in the Equatorial Eastern Pacific are analysed. The results show that there are two peaks in the spectrum. One is the low frequency oscillation with a period of 3.- 5 years, and the other is the quasi-biennial oscillation. The former shows a westward migration in the warm episode of SSTA and the latter has the opposite trend. The El Nino events will be formed while the two frquency bands are in phase in the warming stage of SSTA in the Equatorial Eastern Pacific

关键词： Nino EI SSTA The low frequency oscillations of the sea surface temperature in the Equatorial Eastern Pacific and El Nino formation El

The three-layer model of the thermohaline structure in the shallow seas

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Acta oceanologica Sinica 1993年第3期12卷 323-334页

作者： Yang Dianrong Institute of Physical oceanography ,ocean university of {3.,{3. 2.6003. china

A three-layer model of the thermohaline structure is developed on the basis of the two -layer model of thermocline. The model is able to simulate the depth,thickness and intensity of both thermocline and halocline, and the temperature and salinity of both upper layer and lower layer in the shallow *** of simulation with data is *** analysis is made on a variety of factors affecting the intensity of the thermocline.

关键词： Three-layer model thermocline shallow sea

On the fundamental dynamics of barotropic circulation in shallow seas

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Acta oceanologica Sinica 1990年第3期9卷 315-329页

作者： Feng Shizuo ocean university of qingdao, qingdao, china

It is suggested that the shallow sea circulation should be related to the Lagrangian residual circulation but not to the conventional Eulerjan mean circulation, and further, the first order Lagrangian residual circulation-the mass-transport velocity field is used to define the steady circulation as the lowest order shallow sea *** set of equation governing the shallow sea circulation is reformulated, which shows that there are no the so-called “tidal surface source” and the “tidal stress”. A vorticity equation for the stream function of horizontal transports is derived, which is easily solved by the conventional numerical *** intertidal convection-diffusion equation governing the concentration of conservative and passive tracer is derived. Differing from the conventional equation, the equation derived in the present paper reveals the Lagrangian convection and has no need to introduce the artificial hypothesis for the so-called “tidal dispersion”.The theory presented here is based on a three-dimensional weakly nonlinear dynamic system.

关键词： shallow tidal vorticity convection Lagrangian conservative governing Bohai Eulerian salinity

Structural control of the Gagua “Wedge” Zone east of Taiwan Island on the southern Okinawa Trough

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Science china Earth Sciences 2005年第8期48卷 1165-1174页

作者： ZHENG Yanpeng1,2,3. LIU Baohua2,3. WU Jinlong2, LIANG Ruicai2,3. LIU Chenguang2,3.& ZHANG Zhengmin1 1. Marine Geology College, ocean university of china,{3. 2. First Institute of oceanography, State oceanic Administration, qingdao 266061, china 3. Key Laboratory of Marine Sedimentology and Environmental Geology, State oceanic Administration, qingdao 266061, china Marine Geology College Ocean University of China Qingdao China First Institute of oceanography State Oceanic Administration Qingdao China Key Laboratory of Marine Sedimentology and Environmental Geology State Oceanic Administration Qingdao China

Based on compositive analysis and interpretation of the observed and historical data, the geophysical field characters and structural properties of the Gagua “Wedge” Zone of the sea area east of Taiwan Island and the primary tectonic stress direction and its variabilities of backarc spreading in the southern Okinawa Trough are studied. It is concluded from the study results that the Gagua “Wedge” Zone is structurally consistent with the Gagua ridge and two fault basins on both sides of the Gagua ridge, and adjusts the moving direction and distance of the western Philippine Sea plate to make the northwestward motion of the plate on its east side change to the northward subduction of the plate on its west side so that the primary tectonic stress direction of the Okinawa Trough changed from NW-SE to nearly N-S, which provided the stress source for the Okinawa Trough to enter the second spreading stage.

关键词： east of Taiwan Island, Gagua "Wedge" Zone, Okinawa Trough, structural control.

A NOTE ON THE BACKWARD ERRORS FOR INVERSE EIGENVALUE PROBLEMS

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Journal of Computational Mathematics 2003年第2期21卷 201-206页

作者： Xinguo Liu Zhengjian Bai (Department of Mathematics, ocean university of china, {3. 266071) Departmenl of Mathematics Ocean University of China Qingdao 266071

In this note, we consider the backward errors for more general inverse eigenvalue problems by extending Sun's approach. The optimal backward errors are defined for diagonal-ization matrix inverse eigenvalue problem with respect to an approximate solution, and the upper and lower bounds are derived for the optimal backward errors. The results may be useful for testing the stability of practical algorithms.

关键词： Inverse eigenvalue problem Optimal backward error Upper bound Lower bound

Stable biomimetic film on Fe_3.l surface for corrosion resistance in seawater

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Science china(Technological Sciences) 2008年第7期51卷 975-978页

作者： CHEN ShouGang, LIU Tao & YIN YanSheng Institute of Materials Science and Engineering, ocean university of china, {3. 266100, china Institute of Materials Science and Engineering Ocean University of China Qingdao China

Stable superhydrophobic n-tetradecanoic acid (CH3.CH2)14COOH) film was pre- pared by means of sol-gel and self-assembly techniques, with a very high seawater contact angle (158°) and a small sliding angle (3.l with the biomimetic superhydrophobic film surface is improved obviously when compared with pure Fe3.l sample by measurement of electrochemical impedance spectroscopy (EIS).

关键词： corrosion thin films coatings Fe3.l nanocrystalline materials

A vortex induced vibration of marine riser in waves

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Acta oceanologica Sinica 2011年第4期30卷 96-101页

作者： LOU Min DONG Wenyi GUO Haiyan College of Petroleum Engineering China University of Petroleum （East China） Dongying257061 China Offshore Oil Engineering （qingdao） Company Limited Qingdao 266520 China College of Engineering Ocean University of China Qingdao 266071 China

A marine riser transporting fluid in the Bohai Sea was selected as study object,using an experi-mental and numerical method to study its vortex induced vibration in waves. A similarity theory was used in the experiment to derive the experimental model from a practical model,the dy-namic response of a riser model was measured in waves. A corresponding numerical simulation was performed using a finite element method. Comparisons were made with the results between the experiment and the numerical simulation. Some valuable results were obtained.

关键词： riser VIV wave experiment

Hydrocarbon test in lower-layer atmosphere to predict deep-sea petroleum or hydrate in the Okinawa Trough: an example

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Acta oceanologica Sinica 2003年第4期22卷 569-576页

作者： Gong Jianming1, Chen Jianwen 1, 2, Li Gang1, Zhang Xunhua1, Li Jipeng3. Huang Fulin1 1. qingdao Institute of Marine Geology, qingdao 266071, china. 2. {3. university of china, qingdao 2.6003. china 3. Hefei Institute of Petroleum Chemical Exploration, china Petroleum Exploration and Development Research Institute, Hefei 23.022,china qingdao Institute of Marine Geology Qingdao 266071 China ocean university of china Qingdao 266003 China Hefei Inst. Petroleum Chem. Explor. China Petroleum Explor./Devmt. Res. Hefei 230022 China

Light hydrocarbon (methane, ethane, propane, butane and CO2) test and C isotopic analysis of CO are conducted for over 100 lower-layer atmospheric samples from the East china Sea slope and the Okinawa Trough. The results show that the lower-layer atmosphere mainly consists of CO2 and then of CH4, and the CO2 concentrations are calculated to have a high average value of 0.87 omega/10(-2) about three times that of the regional background (0-3.omega/10(-2)). The result also shows that the average value of C isotope - 20.8 x 10(-3. is given to the CO2, inferring that it is inorganic gas. Thus, for the future 's work in the Okinawa Trough, special attention should be paid to CO2 hydrate, which is very possibly an important hydrate type.

关键词： lower-layer atmosphere hydrocarbon test C isotopic analysis deep-sea petroleum gas hydrate