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A maximum entropy distribution for wave heights of non-linear sea waves

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Progress in Natural Science:Materials International 2007年第11期17卷 1318-1326页

作者： Zhou Liangming1, Xu Delun1, Wang Aifang1, Chen Zhengshou2 and Yan Xiuhua1(1. Physical oceanography Laboratory, Ocean university of china, {3. 266100,china 2.Engineering College, Ocean university of china, {3. 266071, china) Physical oceanography Laboratory Ocean University of China Qingdao 266100 China Engineering College Ocean University of China Qingdao 266071 China

Based on the maximum entropy principle,a probability density function (PDF) for the zero-crossing wave height (H) of random waves is derived as the simple form fn(H)=αHγe-βHn (n is a selectable positive integer) through solving a variational problem subject to some quite general constraints. This PDF maximizes the information entropy of H, and its parameters α, γ and β are expressed explicitly in terms of the distribution moments m, m=1,2,…,n, so it is well competent for describing the distribution of H of nonlinear sea waves with large uncertainty, and its parameters can be simply determined from available data. Comparisons between the PDF with n=3.and n=4 and the observed distributions of H from wave records measured in the East china Sea and in a wind-wave tunnel show fairly satisfying agreements.

关键词： sea waves the maximum entropy principle probability density function

Semi-analytical analysis of the response of the air temperature over the land surface to the global vegetation distribution

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Chinese Science Bulletin 2009年第14期54卷 2499-2505页

作者： LIU Fei1,2 & CHAO JiPing3.4 1 Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 100029, china 2 Graduate university of Chinese Academy of Sciences, Beijing 100049, china 3.National Marine Environmental Forecasting Center, Beijing 100081, china 4 First Institute of oceanography, State Oceanic Administration of china, qingdao 266061, china Institute of Atmospheric physics Chinese Academy of Sciences Beijing China Graduate university of Chinese Academy of Sciences Beijing China National Marine Environmental Forecasting Center Beijing China First Institute of oceanography State Oceanic Administration of China Qingdao China

Response of the air temperature over the land surface to the global vegetation distribution is investigated, using a three-dimensional governing equation to simulate the steady, large-scale, limited amplitude perturbation of the free, inviscid and adiabatic atmosphere. The adoption of the static equation leads to a temperature governing equation in the terrain following coordinate. With the prescribed temperature as the upper boundary condition and the radiation balance as the lower boundary condition, the semi-analytical solution of the global circulation temperature can be calculated. In this article, only the air temperature (at 2 m height) over the land surface is analyzed, and the result suggests that this model can simulate the air temperature pattern over the land surface reasonably. A better simulation occurs when a simple feedback of the albedo on the temperature is included. Two sensitivity experiments are analyzed through this model. One suggests that the air temperature over the land surface descends obviously when the land surface is covered with ice all over, while another suggests that the air temperature rises a little when the land surface is covered with forest except the ice-covered area. This model appears to be a good tool to study the response of the air temperature to the vegetation distribution. Limitations of the model are also discussed.

关键词：空气温度植被分布陆地表面反应解析分析模拟模式控制方程边界条件

Orthogonal design for optimization of pigment extraction from surface sediments of the Changjiang River Estuary

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Acta Oceanologica Sinica 2011年第4期30卷 33-42页

作者： ZHAO Jun YAO Peng YU Zhigang Thomas S Bianchi Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China Qingdao 266100 China department of oceanography Texas A ＆ M University College Station TX 77843 USA Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education Ocean University of China Qingdao 266100 China Institute of Marine Organic Geochemistry College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 China

Using a suitable solvent for extracting pigments from sediment for high performance liquid chromatography（HPLC） analysis is critical for obtaining qualitative and quantitative estimates of phytoplanktonic and benthic algal biomass,as well as community composition. Five methodological factors（sample dehydration,extraction solvent,extraction duration,number of extractions,and ratio of solvent volume：sample weight） were studied using an L 9（3.4 ） orthogonal design in a sedimentary pigment extraction experiment on samples collected from the Changjiang large-river delta-front estuary（LDE）,using HPLC analysis. The results show that the optimal extraction method for sedimentary pigments should include freeze-drying samples prior to extraction. The effects of different factors on sedimentary pigment extraction were separated by the L 9（3.4 ） orthogonal design experiments and showed that the extraction solvent was the most important,with extraction duration the second most important,and numbers of extraction and ratio of solvent volume：sample weight was the least important. The mixed solvent treatment comprised of acetone,methanol and water（80：15：5,by volume） was best for polar pigment extraction,with 100% acetone better for apolar pigments. For most pigments employed in this study（i.e.,peridinin,fucoxanthin,alloxanthin,diatoxanthin,zeaxanthin,pheophytin-a and β-carotene） ,3.h was found to be enough time for extraction from these deltaic sediments. However,for chlorophyll-a,the most important pigment used for estimating algal biomass,12 h was needed. A small amount of solvent（3.ml） with duplicate extractions obtained the greatest amount and diversity of pigments. Unfortunately,no extraction method was found to be suitable for all pigments in sediments. The choice of extraction procedure should be made in accordance with the objective of each study,taking into consideration the properties of sediments and pigments in question.

关键词： sedimentary pigments extraction orthogonal design HPLC Changjiang River Estuary

C-banding pattern and nucleolar organizer regions of Cynoglossus semilaevis Günther, 1873

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Progress in Natural Science:Materials International 2006年第7期16卷 769-772页

作者： WU Di, ZHANG Shicui, ZHUANG Zhimeng, PANG Qiuxiang, WANG Changliu and WAN Ruijing ( department of Marine Biology, Ocean university of china,{3. Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, qingdao 266071, china department of Biology, Yantai Normal university, Yantai 264025, china) Ocean Univ china Dept Marine Biol Qingdao 266003 Peoples R China Chinese Acad Fishery Sci Yellow Sea Fisheries Res Inst Qingdao 266071 Peoples R China Yantai Normal Univ Dept Biol Yantai 264025 Peoples R China

The C-banding pattern and nucleolar organizer regions of the metaphase chromosomes of Cynoglossus semilaevis are reported. The interstitial regions in all chromosomes including the pair of sex chromosomes had positive C-bands, and the 6th and 12th pairs of chromosomes were entirely stained in most cases. Some chromosomes such as the 1st, 2nd, 7th, 8th, 9th and 10th pairs showed C-bands at centromeric or distal ends. The C-banding heretochromatin occupies 3..03. of the total chromosome surface in C. semilaevis, which is similar to that of amphibians such as Mixophyes fasciolatus (3.. 2% ) and M. schevilli (20. 7% ), but is rather lower than that of cephalochordate Branchiostoma belcheri (54. 3.% ). Silver staining revealed a single pair of nucleolar organizer regions ( NORs) located in the telomeric regions of Chromosome 2. The association of NORs with heterochromatin observed in vertebrates also occurs in C. semilaevis as the telomeric regions of Chromosome 2 are always stained positively with C-banding.

关键词： Cynoglossus semilaevis karyotype C-banding NORs.

Eigen solutions of internal waves over subcritical topography

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Acta Oceanologica Sinica 2011年第2期30卷 1-8页

作者： DAI Dejun WANG Wei ZHANG Qinghua QIAO Fangli YUAN Yeli The First Institute of oceanography State Oceanic Administration Qingdao 266061 China Key Laboratory of Marine Science and Numerical Modeling State Oceanic AdministrationQingdao 266061 China Physical oceanography Laboratory Ocean University of China Qingdao 266003 ChinaP~eceived 13 June 2010 accepted 2 December 2010

Diapycnal mixing plays an important role in the ocean *** waves are a kind of bridge relating the diapycnal mixing to external sources of mechanical *** in obtaining eigen solutions of internal waves over curved topography is a limitation for further theoretical study on the generation problem and scattering *** this study,a kind of transform method is put forward to derive the eigen solutions of internal waves over subcritical topography in twodimensional and linear *** transform converts the curved topography in physical space to flat bottom in transform space while the governing equation of internal waves is still hyperbolic if proper transform function is ***,one can obtain eigen solutions of internal waves in the transform *** examples of transform functions,which convert the linear slope,the convex slope,and the concave slope to flat bottom,and the corresponding eigen solutions are illustrated.A method,using a polynomial to approximate the transform function and least squares method to estimate the undetermined coefficients in the polynomial,is introduced to calculate the approximate expression of the transform function for the given subcritical topography.

关键词： internal waves transform method eigen solutions subcritical curved topography

OSCILLATION CRITERIA FOR NONLINEAR SECOND ORDER ELLIPTIC DIFFERENTIAL EQUATIONS

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Chinese Annals of Mathematics,Series B 1996年第1期17卷 89-102页

作者： ZHANG BINGGEN ZHAO TAO B. S. LALLI (department of Mathematics, Ocean university of qingdao,{3..)(department of Mathematics, Arizona State university, U.S.A.)(Departmemt of Mathematics, university of Saskatchewan, Canada.) 青岛海洋大学数学系山东青岛 Arizona State university 美国 university of Saskatchewan 加拿大

The second order elliptic differential equations are considered in an exterior domain Ω Rn, n≥2, where p can chang sign. Some new sufficient conditions for the oscillation of solutions of (1.1) and (1.2) are establi... 详细信息

关键词： Oscillation Nonlinear elliptic equation Riccati inequality

Nonlinear tidal waves in a kind of estuary with gradually varying cross-section

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Acta Oceanologica Sinica 1990年第1期9卷 37-50页

作者： Du Yong, Chen Zongyong and Ye Anle department of Physical oceanography and Marine Meteorology, Ocean university of {3., {3., china

-Nonlinear tidal waves in a kind of estuary are studied in the paper using one-dimensional nonlinear hydrody-namic equations with friction. The estuary has exponentially varying width B=B0 e-bx and uniform depth h. The one-dimensional hydrodynamic equations are solved by perturbation method. It was found that our solution included two special cases, Pelisenpeki's solution and Airy's solution. The former can be got by letting b=0 in our solutions, and the latter by setting 6 = 0 and f= 0 (f is linear frictional coefficient). In terms of the second-order solution, the physical mechanism of nonlinear tidal waves in estuaries with gradually varying cross-section is explored. It is shown that, under the assumption of linear friction coefficient, shallow water constituent waves consist of two parts, one is produced by shallow water nonlinear effect outside the estuary, the other is generated by shallow water nonlinear effect inside estuary. In addition, the physical mechanism of the residual tidal current and elevation are not exactly the same as that of the shallow water constituent waves. The former results from the interaction of shallow water nonlinear effect, friction and estuarine deforming effect. The latter depends chiefly on shallow water nonlinear effect. Finally, present nonlinear model is applied to the modelling of the tidal waves in the Hangzhou Bay. Seven of constituent waves (O1,K1, M2, S2, M4, S4, MS4) are taken into account. It will be found that the results modelled by incident progressive waves and their interaction agree rather well with the observations, therefore, it can be concluded that the incident progressive waves in the Hangzhou Bay are dominant.

关键词： tidal estuary shallow frictional hydrodynamic perturbation tides latter exponentially currents

A NONHYDROSTATIC NUMERICAL MODEL FOR DENSITY STRATIFIED FLOW AND ITS APPLICATIONS

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Journal of Hydrodynamics 2008年第6期20卷 706-712页

作者： LI Qun XU Zhao-ting Polar Research Institute of china （PRIC） Shanghai 200136 China Physical oceanography Institute Ocean University of China Qingdao 266100 China

A modular numerical model was developed for simulating density-stratified flow in domains with irregular bottom topography. The model was designed for examining interactions between stratified flow and topography, e.g,, tidally driven flow over two-dimensional sills or internal solitary waves propagating over a shoaling bed. The model was based on the non-hydrostatic vorticity-stream function equations for a continuously stratified fluid in a rotating frame. A self-adaptive grid was adopted in the vertical coordinate, the Alternative Direction Implicit （ADI） scheme was used for the time marching equations while the Poisson equation for stream-function was solved based on the Successive Over Relaxation （SOR） iteration with the Chebyshev acceleration. The numerical techniques were described and three applications of the model were presented.

关键词： nonhydrostatic assumption stratified flow self-adaptive grid nonlinear internal wave

Fate of particle-reactive pollutants in the Xiamen Bay

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Acta Oceanologica Sinica 1998年第4期17卷 503-508页

作者： Chen Min and Huang Yipu (department of oceanography, Xiamen university, Xiamen 3.1005, {3.) department of oceanography Xiamen University Xiamen 361005 China

A simple model is established to describe the fate of particle-reactive pollutants in the Xiamen Bay. Based on the conditional distribution coefficients (Kd ) of chemicals and residence times of particle and waters, the model can be used to predict the fractions of pollutants which would be scavenged to sediments and would escape from the system. The model is calibrated using scavenging data derived from 23. Th - 23.U disequilibrium. The fate of a potential pollutant which will be scavenged is a function of the properties of the chemical, of the particle dynamics, and of the waters dynamics in the environment. It is inappropriate to overlook any factor.

关键词： Pollutant, ^(23.)Th/^(23.)U disequilibrium model prediction