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A UNIVERSAL IN TAILING WAVETRAIN GENERATION

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Journal of Hydrodynamics 2004年第5期16卷 603-607页

作者： XUZhao-ting SAMUELS.p.shen QIAOFang-li InstituteofphysicalOceanographyandphysicalOceanographyLaboratory OceanUniversityofChinaQingdao266003China DepartmentofMathematicsScience UniversityofAlbertaEdmontonT6G2G1Canada KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China

A universal in tailing wave-train generation of forced soliton generationover topography is found theoretically as the flows are at the resonant points and it is examinedwith the numerical calculation of the corresponding fKdV e-quatioa From the comparisons, it is shownthat theoretical and numerical results on the invariance is in good agreement and the theory givenin this paper does not include the modulus truncation, any free constant and unknown function.

关键词： universal soliton tailing wave-train fKdV equation KdV equations

NONLINEAR MODULATION OF THE SHORT INTERNAL WAVES IN THE WEAKLY STRATIFIED OCEAN

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Chinese Journal of Oceanology and Limnology 1991年第4期9卷 364-374页

作者：徐肇廷 shen S.p. Ocean University of Qingdao 266003University of Saskatchewan Canada S7N OW0

A nonlinear evolution equation of 2 - D short internal waves under condition of weak stratification-cubic Schrodinger equation- is derived by using the reductive perturbation method. Because aB perturbation for the harmonic wave modulation is neutrally stable. At the same time, there is also a sort of wave pack -et-KdV envelope soliton. In the nonlinear system the dark soliton is obtained under condition of weak stratification. It is shown that the vertical perturbation of the Brunt-Vaisala frequency plays a role in forming the KdV envelope soliton and dark soliton.

关键词： perturbation soliton stratification cubic harmonic envelope stratified solitary Boussinesq trivial

A mathematical solution for the parameters of three interfering resonances

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Chinese physics C 2018年第4期42卷 62-68页

作者： X. Han C.p. shen School of physics and Nuclear Energy Engineering Beihang University Beijing 100191 China

The multiple-solution problem in determining the parameters of three interfering resonances from a fit to an experimentally measured distribution is considered from a mathematical viewpoint. It is shown that there are four numerical solutions for a fit with three coherent Breit-Wigner functions. Although explicit analytical formulae cannot be derived in this case, we provide some constraint equations between the four solutions. For the cases of nonrelativistic and relativistic Breit-Wigner forms of amplitude functions, a numerical method is provided to derive the other solutions from that already obtained, based on the obtained constraint equations. In real experimental measurements with more complicated amplitude forms similar to Breit-Wigner functions, the same method can be deduced and performed to get numerical solutions. The good agreement between the solutions found using this mathematical method and those directly from the fit verifies the correctness of the constraint equations and mathematical methodology used.

关键词： multiple solutions three interfering resonances high energy physics experiments

Analysis of Sampling Error Uncertainties and Trends in Maximum and Minimum Temperatures in China

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Advances in Atmospheric Sciences 2014年第2期31卷 263-272页

作者： HUA Wei Samuel S.p.shen WANG Huijun Nansen-Zhu International Research Centre Institute of Atmospheric physics Chinese Academy of Sciences Department of Atmospheric Sciences Chengdu University of Information Technology University of the Chinese Academy of Sciences Department of Mathematics and Statistics San Diego State University

In this paper we report an analysis of sampling error uncertainties in mean maximum and minimum temperatures （Tmax and Tmin） carried out on monthly,seasonal and annual scales,including an examination of homogenized and original data collected at 731 meteorological stations across China for the period *** of the gridded data and national average,linear trends and their uncertainties,as well as the homogenization effect on uncertainties are *** is shown that the sampling error variances of homogenized Tmax and Tmin,which are larger in winter than in summer,have a marked northwest-southeast gradient distribution,while the sampling error variances of the original data are found to be larger and *** and Tmin increase in all months of the year in the study period 1951-2004,with the largest warming and uncertainties being 0.400℃ （10 yr）-1 ＋ 0.269℃ （10 yr）-1 and 0.578℃ （10 yr）-1 ＋ 0.211℃ （10 yr）-1 in February,and the least being 0.022℃ （10 yr）-1 ＋ 0.085℃ （10 yr）-1 and 0.104℃ （10 yr）-1 ＋0.070℃ （10 yr）-1 in *** can remove large uncertainties in the original records resulting from various non-natural changes in China.

关键词： sampling error uncertainty maximum temperature minimum temperature temperature trend

Noble gas isotopes in natural gases from Central and Northwest China

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Chinese Science Bulletin 1997年第10期42卷 838-841页

作者： Xu, S Xu, YC shen, p Nakal, S Wakita, H State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Lanzhou China Laboratory for Earthquake Chemistry Faculty of Science University of Tokyo China

As chemically inert elements,the variations of noble gas abundance and isotope during geologi-cal processes are not significantly affected by complex chemical process but mainly depend onthe control of physical processes such as solution,absorption,adsorption and nuclear ***,studies on noble gas geochemistry will play an important role in the geologi-cal processes such as genesis of natural *** this purpose,this study has measured 4 CH4-rich natural gases in sedimentary basins from Central and Southwest China for all noble

关键词： natural gas noble gas isotope crustal component.

pROpERTIES OF W/Cu FGMs CONTAINING 1%TiC OR 1%La_2O_3 pREpARED USING GSUHp

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Acta Metallurgica Sinica(English Letters) 2007年第1期20卷 59-64页

作者： K. Zhang W.p. shen C.C. Ge Laboratory of Special Ceramics and powder Metallurgy University of Science and Technology Beijing Beijing 100083 China

W/ Cu functionally gradient materials （FGMs） containing 1% La2O3 and 1% TiC were prepared using graded sintering under tdtra-high pressure （GSUHp）. The specimens have been found to exhibit low porosity （11.57% and 11.35%, respectively）. Shearing strength of the specimens between layers is good. Moreover, the specimens have still demonstrated good performance in testing thermal-shock resistance. When power density of laser is 200MWm^-2, the specimens have been tested for thermal-shock resistance （1000 times）; the specimens that contained 1%La2O3 were not subjected to damage, whereas those that contained 1%TiC began to crack. Finally, effect of additives on thermal-shock resistance was also preliminarily discussed.

关键词： W/Cu FGMs (functionally gradient materials) GSUHp (graded sintering under ultra-high pressure) shearing strength, thermal-shock resistance

An Approach to Quantify the Heat Wave Strength and price a Heat Derivative for Risk Hedging

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Advances in Atmospheric Sciences 2012年第1期29卷 1-9页

作者： Samuel S. p.shen Benedikt KRAMpS Shirley X.SUN Barbara BAILEY Department of Mathematics and Statistics San Diego State University

Mitigating the heat stress via a derivative policy is a vital financial option for agricultural producers and other business sectors to strategically adapt to the climate change scenario. This study has provided an approach to identifying heat stress events and pricing the heat stress weather derivative due to persistent days of high surface air temperature （SAT）. Cooling degree days （CDD） are used as the weather index for trade. In this study, a call-option model was used as an example for calculating the price of the index. Two heat stress indices were developed to describe the severity and physical impact of heat waves. The daily Global Historical Climatology Network （GHCN-D） SAT data from 1901 to 2007 from the southern California, USA, were used. A major California heat wave that occurred 20-25 October 1965 was studied. The derivative price was calculated based on the call-option model for both long-term station data and the interpolated grid point data at a regular 0.1~ x0.1~ latitude-longitude grid. The resulting comparison indicates that （a） the interpolated data can be used as reliable proxy to price the CDD and （b） a normal distribution model cannot always be used to reliably calculate the CDD price. In conclusion, the data, models, and procedures described in this study have potential application in hedging agricultural and other risks.

关键词： heat derivative price heat wave risk cooling degree day call option payoff southern California

UV/TiO_2 and UV/TiO_2-film for Degradation of Textile Dyes

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武汉理工大学学报 2007年第10期29卷 200-208页

作者： Ruth Yu-li Yeh shen p W Liu Robert Hung Yung-tse Department of Chemical Engineering Minghsin University of Science and Technology Department of Civil Engineering Cleveland State UniversityCleveland

This research focused on the feasibility and treatment efficiency of Advance Oxidation process(AOp)-UV/TiO2 for three different kinds of simulated dye wastewater(FBL,FBB and S-RL).The first part of this study investigated the treatment of simulated dye wastewater with UV/TiO2 by changing TiO2 dosages,TiO2 particle sizes and dye *** efficiency was measured by color removal and TOC *** optimum conditions obtained for treatment of different dye wastewater were *** treatment of Indanthrene red(FBB) by UV/TiO2 was the best,with 99.68% of TOC removal percentage and nearly 100% of color removal while treatment of FBL with 96.11% of TOC removal and almost 100% of color *** removal efficiency was lowest for S-RL dye solution with 81.88% of TOC and 95.87% for color *** Langmuir adsorption isotherm and modified Langmuir-Hinshelwood kinetic model(modified L-H model) were fitted to the experimental data and were able to correlate the adsorption patterns and the kinetics of the dyes *** the photocatalysts(TiO2) used were nano-sized powder and is difficult to separate from the wastewater,the second part of this research focuses on the preparation of TiO2-film on glass-substrate and the treatment of simulated FBL dye wastewater by UV/TiO2-film oxidation then *** experimental results showed the TiO2-films are suitable only for the dye wastewater treatment in low concentration.

关键词：紫外线二氧化钛二氧化钛薄膜纺织染色氧化降解吸附等温线

Intermediately Complex Models for the Hydrological Interactions in the Atmosphere-Vegetation-Soil System

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Advances in Atmospheric Sciences 2006年第1期23卷 127-140页

作者：曾晓东王爱慧曾庆存 Robert E. DICKINSON Xubin ZENG Samuel S. p. shen The University of Arizona Tucson AZ USA University of Alberta Edmonton AB Canada Institute of Biophysics Chinese Academy of Sciences Beijing Institute of Atmospheric physics Chinese Academy of Sciences Beijing Georgia Institute of Technology Atlanta GA USA

This paper investigates the hydrological interactions in the atmosphere-evegetation-soil system by using the bucket model and several new simplified intermediately complex models. The results of mathematical analysis and numerical simulations show that these models, despite their simplicity, can very clearly reveal the essential features of the rather complex hydrological system of atmosphere-ecosystem-soil. For given atmospheric variables, these models clearly demonstrate multiple timescales, the ＂red shift＂ of response spectra, multi-equilibria and limit cycles, bifurcation, abrupt change, self-organization, recovery, ＂desertification＂, and chaos. Most of these agree with observations. Especially, the weakening of ＂shading effect＂ of living canopy and the wilted biomass might be a major mechanism leading to the desertification in a relatively short period due to overgrazing, and the desertification in a relatively long period or in climate of change might be due to both Charney＇s mechanism and the shading effect. These ideas could be validated with further numerical simulations. In the paper, some methods for improving the estimation of timescales in the soil water evolution responding to the forcing are also proposed.

关键词： Atmosphere-vegetation-soil system hydrological process multi-equilibria chaos desertification shading effect