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Science china Mathematics 2010年第10期53卷 2679-2696页

作者： YANG JiMing1,& CHEN YanPing2 1College of Science,Hunan institute of Engineering,Xiangtan 411104,china 2School of Mathematical Sciences,South china Normal University,Guangzhou 51063.,china College of Science Hunan Institute of Engineering Xiangtan China School of Mathematical Sciences South China Normal University Guangzhou China

A kind of compressible miscible displacement problems which include molecular diffusion and dispersion in porous media are investigated.A symmetric interior penalty discontinuous Galerkin (SIPG) method is applied to the coupled system of flow and *** the induction hypotheses instead of the cut-off operator and the interpolation projection properties,a priori hp error estimates are *** error bounds in L2(H1) norm for concentration and in L∞(L2) norm for velocity are optimal in h and suboptimal in p with a loss of power 1/2.

关键词： a priori error discontinuous Galerkin compressible miscible displacement coupled system

Laser　Rapid　Melting　Structure　and　Property　for　Ni－based　Tungsten　Carbide　Alloy

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Chinese Journal of Lasers 1996年第4期B5卷 379-384页

作者： ZHANG Song KANG Yuping SONG Huan, ZHU Jingpu(Shenyang Polytechnic University,Shenyang 110023. china)ZHANG Chunhua(Shenyang Plant,Shenyang 110026, china)ZHAO Fangxin(Shenyang Research institute of Foundry,Shenyang 110021, china) Shenyang Polytechnic Univ Shenyang China

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关键词： laser rapid melting Ni-based tungsten carbide alloy microstructure transformation property

An improvement of the too cold tongue in the tropical Pacific with the development of an ocean-wave-atmosphere coupled numerical model

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Progress in Natural Science:Materials International 2007年第5期17卷 576-583页

作者： Song Zhenya, Qiao Fangli, Yang Yongzeng and Yuan Yeli (The First institute of Oceanography, SOA, Qingdao 266061, china) The First institute of Oceanography SOA Qingdao 266061 China

A common problem in the application of the coupled ocean-atmosphere general circulation models (CGCMs) without flux correction is that the simulated equatorial cold tongue in general tends to be too strong, narrow, and extending too far west. The causes are not well understood yet. One possible reason may be the simulated mixed layer depth (MLD) is too shallow in the tropical Pacific due to insufficient vertical mixing in the OGCM. It is believed that the wave-induced vertical mixing can greatly improve the simulation of the MLD and thermocline structure. In this study, the coupled ocean-atmosphere general circulation model (FGCM-0) incorporated with wave-induced mixing has been employed to simulate the tropical Pacific sea surface temperature (SST). Generally, the wave-induced mixing lowers the SST in the OGCM because the strengthened vertical mixing can bring more cold water upward. However, in the coupled model, the non-uniformity of the space distribution in SST drop generates a horizontal gradient of the sea surface air pressure, and thus yields surface wind field anomaly. The wind anomaly leads to both ocean surface circulation anomaly and downwelling anomaly, which can restrain the overly-westward extension of the cold tongue in the tropical Pacific. Compared with the model results from the original model (FGCM-0), the modeled SST is higher by more than 0.8℃, with a maximum of 1.2℃in the western Pacific (160—180°E, 0—3.N) . The eastern boundary of the isotherm of 26. 0℃also moves from 165°E to 180°E. The overly westward extension of the simulated equatorial cold tongue is suppressed with the incorporation of the wave-induced mixing in the coupled model. The simulated SST shows in general improved results with a maximum improvement of more than 1.0℃. The simulated SST improvement in the north tropical Pacific is much better than that of the south tropical Pacific.

关键词： cold tongue wave-induced mixing the conpled ocean-atmosphere general circulation models the tropical Pacific

A semantic geographical knowledge wiki system mashed up with Google Maps

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Science china(Technological Sciences) 2010年第S1期53卷 52-60页

作者： GAO Yong,GAO Song,LI RunQiang & LIU Yuinstitute of Remote Sensing and Geographical Information Systems,Peking University,beijing 100871,china institute of Remote Sensing and Geographical Information Systems Peking University Beijing China

A wiki system is a typical Web 2.0 application that provides a bi-directional platform for users to collaborate and share much useful information ***,computers cannot well understand the wiki pages in plain *** user-generated geographical content via wiki systems cannot be manipulated properly and efficiently unless the geographical semantics is explicitly *** this paper,a geographical semantic wiki system,Geo-Wiki,is introduced to solve this ***-Wiki is a semantic geographical knowledge-sharing web system based on geographical ontologies so that computers can parse and storage the multi-source geographical ***,Geo-Wiki mashed up with map services enriches the representation and helps users to find spatial distribution patterns,and thus can serve geospatial decision-making by customizing the Google Maps APIs.

关键词： geo-ontology semantic wiki mashup Google Maps

VARIATIONAL ITERATION SOLVING METHOD FOR SEA-AIR OSCILLATOR MODEL OF INTERDECADAL CLIMATE FLUCTUATIONS

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Chinese Geographical Science 2005年第3期 37-40页

作者： MO Jia-qi1, 2, LIN Yi-hua3. WANG Hui4 (1. Department of Mathematics,Anhui Normal University,Wuhu 241000,P. R. china 2. Division of Computational Science E-institutes of Shanghai Universities at Shanghai Jiaotong University,Shanghai 200240,P. R. china 3. institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 100029,P. R. china 4. Chinese Academy of Meteorological Sciences,beijing 100081,P. R.china) Department of Mathematics A nhui Normal UniversityWuhu 241000P. R. China Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong UniversityShanghai 200240P. R. China institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029P. R. China Chinese Academy of Meteorological Sciences Beijing 100081P. R. China

Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively.

关键词： nonlinear variational iteration El Nio-Southern Oscillator model

A tentative discussion on the method ofcomprehensive integration of geographicinformation

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Journal of Geographical Sciences 1999年第2期9卷 169-174页

作者： QIU You-liang CHEN Bing-xian (institute of Geography, Chinese Academy of Sciences, beijing 100101, china. Department of Urban and Resources Science, Naming University, Naming 210093. china)

In the era of information, geography has made remarkable progress in the development of its research objective and approaches. Geographic information System (GIS), which is similar to the quantitative geography developed in the 1950s to the 1970s, is broadly accepted in moderm ***, limitations caused by the functions of GIS, and the complexity of geographic environment has provoked people to find a new research method to meet the demand stemmed from geographical researches. This paper firstly looks back on the history of geographical research methods and makes an analysis of their limitations', then, makes a prospective view on the GIS and its related *** on thes, the paper presents a new research method: comprehensive integration of geographic information, which is guided by Meta-Synthetic-Engineering in methodology and supported by modem technology. Aiming to exploit a kind of research method, discussion on comprehensive integration of geographic information is given to try to answer how geography will develop in the era of information. It will help us to realize much higher hierarchical and macro-systematic comprehension about geographic environment.

关键词： geographic information system quantitative revolution integration meta-synthetic engineering

Sedimentary environment and development controls of the hydrocarbon source beds: Middle and Upper Proterozoic in northern North china

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Science china Earth Sciences 2004年第Z2期47卷 133-140页

作者： BAO Zhidong1,2, CHEN Jianfa1, ZHANG Shuichang3. ZHAO Hongwen1, ZHANG Qinghai1 & LI Yan1 1. University of Petroleum, beijing 102200, china 2. Key Lab of Petroleum Migration and Accumulation Mechanism of Ministry of Education, beijing 102200, china 3. Petroleum Research institute of Exploration and Development,beijing 100083. china University of Petroleum Beijing 102200 China Key Lab of Petroleum Migration and Accumulation Mechanism of Ministry of Education Beijing 102200 China University of Petroleum Beijing 102200 China Petroleum Research institute of Exploration and Development Beijing 100083 China

Problem on development control of marine source bed hold in Chinese petroleum industry progression. The Hongshuizhuang Formation,Tieling Formation and Xiamaling Forma-tion in the Middle and Upper Proterozoic are important hydrocarbon source beds in northern North china, and investigation of their sedimentary environments and the controls has great significance for petroleum exploration in North china. Based on sedimentology (sequence stratigraphy), palaeoecology, sedimentary geochemistry, and sedimentary palaeogeography, their development pattern is discussed. All these studies indicate that the development controls of the hydrocarbon source beds include a favorite palaeogeographic location, exceeding propa-gation of biomes in low and middle latitudes, anoxic environments, enrichment of phosphorus element and the adsorption of clay minerals during the preservation of organic matter in the ma-rine carbonates.

关键词： hydrocarbon source bed, sedimentary environment, development control, middle and upper Proterozoic, northern North china.

A new inverse filtering method of gravity field

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Acta Oceanologica Sinica 1988年第3期7卷 421-434页

作者： JIN XIANGLONG and GAO ZHIQING Second institute of Oceanography, State Oceanic Administration, Hangzhou, china institute of Marine Geology, Ministry of Geology and Resources, Qingdao, china Second Inst. of Oceanography State Oceanic Administration Hangzhou China China

A new method for inversion of gravity field using the technique of inverse filtering is presented in this paper to calculate the structure of *** inversing gravity data of West Pacific and Okinawa Trough, it has been proven that the method of inverse filtering has many advantages, such as high accuracy, fast convergence rate, small memory space used and arbitrary reduction of sampling interval. This new method is convenient to minicomputer for solving the inverse problem of crustal structure.

关键词： A new inverse filtering method of gravity field

Recent glacial retreat in High Asia in china and its impact on water resource in Northwest china

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Science china Earth Sciences 2004年第12期47卷 1065-1075页

作者： YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.institute of Tibetan Plateau Research,Chinese Academy of Sciences,beijing 100029,china 2.Cold and Arid Regions Environmental and Engineering Research institute,Chinese Academy of Sciences,Lanzhou 73.000,china Chinese Academy of Sciences Institute of Tibetan Plateau Research Beijing China Chinese Academy of Sciences Cold and Arid Regions Environmental and Engineering Research Institute Lanzhou China

Under the impact of climatic warming, the glaciers in the High Asia in china have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in china is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in china has an important impact on the water resource of the arid regions in Northwest china. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest china. In the Tarim River basin, the increase of river runoff is higher than 5.5%.

关键词： High Asia, glacial fluctuation, impact on water resource.

Principle of equipartition of entransy dissipation for heat exchanger design

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Science china(Technological Sciences) 2010年第5期53卷 1309-1314页

作者： GUO JiangFeng,XU MingTian & CHENG Lin institute of Thermal Science and Technology,Shandong University,Jinan 250061,china institute of Thermal Science and Technology Shandong University Jinan China

In the present work,a principle of equipartition of entransy dissipation(EoED) for heat exchanger design is established,which says that for a heat exchanger design with given heat duty and heat transfer area,the total entransy dissipation rate reaches the minimum when the local entransy dissipation rate is uniformly distributed along the heat *** the heat transfer coefficient is unfixed,the total entransy dissipation obtained by the EoED principle is less than that obtained by the principle of equipartition of temperature difference(EoTD).Furthermore,the exchanger effectiveness obtained by the EoED principle is larger than that obtained by the EoTD *** the heat transfer coefficient is fixed,the EoED principle is equivalent to the EoTD *** show that the equipartition of entropy production(EoEP) and EoED principles give rise to difference in entropy generation and entransy dissipation for a heat exchanger optimization *** discrepancies are caused by distinct features of entropy production minimization and entransy dissipation minimization principles,the former is to optimize the design of heat exchanger by making the lost available work minimum,while the latter is not involved with heat-work *** is found that the entropy generation number is not suitable for evaluating heat exchanger performance,since it directly depends on the inlet and outlet temperatures of working *** the contrary,the entransy dissipation number is not directly related to the inlet and outlet temperatures of working ***,the entransy dissipation number is more suitable for serving as a criterion to evaluate heat exchanger performance.

关键词： heat exchanger entropy production entropy generation number entransy dissipation entransy dissipation number