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Study on attribute characterization for reservoir dynamic monitoring by seismic

Science china Earth Sciences 2008年第S2期51卷 218-225页

作者： CHEN XiaoHong1,3.LI JingYe2,3.& ZHAO Wei4.1 Key Lab of Geophysical Exploration of CNPC,china Petroleum university,Beijing 10224.,china 2 Basin & Reservoir Research {3.,china Petroleum university,Beijing 10224.,china 3.State Key Laboratory of Petroleum Resource and Prospecting,china university of Petroleum,Beijing 10224.,china 4.Research {3. of CNOOC,Beijing 100027,china Key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing China State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing China Basin & Reservoir Research center China Petroleum University Beijing China Research center of CNOOC Beijing China

Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

关键词： time-lapse seismic dynamic monitoring rock physical model pre-stack attribute Amplitude Versus Offset (AVO)

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Flux of dimethylsulfide in the Jiaozhou Bay,china

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Journal of Environmental Sciences 1997年第1期9卷 80-85页

作者： Hu Min Tang Xiaoyan center of Environmental Sciences,peking university,Beijing {3.,{4.Li Jinlong Yu Zhongju Department of Technical Physics,peking university,Beijing {3.,{4. center of Environmental Sciences Peking University Beijing 100871 China Department of Technical Physics Peking University Beijing 100871 China

Seasonal measurements of dimethylsulfide(DMS)in surface waters were carried out during 1993.1994.in the Jiaozhou Bay.A seasonal variation is observed for DMS concentrations in seawater,ranging from 0.6 to 8.97 nmol S/L with the highest values in spring.A factor of 4.was measured for DMS concentrations with mean concentrations of 5.85 nmol S/L or 6.58 nmol S/L in spring and 1.4.nmol S/L in winter.A sea-to-air flux of DMS also showed a seasonal variation.

关键词： dimethyl sulfide flux seawater atmosphere.

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Taurine antagonized oxidative stress injury induced by homocysteine in rat vascular smooth muscle cells

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Acta Pharmacologica Sinica 2004年第03期25卷 87-92页

作者： Lin CHANG2,3.Jian-xin XU4.Jing ZHAO5,Yong-zheng PANG2,3.Chao-shu TANG2,3.Yong-fen QI5,6 2Institute of Cardiovascular Diseases,the FirstHospital,peking {4.,Beijing 10003. 3.nstitute of Cardiovascular Diseases,peking {4.,Beijing 100083.4.nstituteof Biophysics,Chinese Academy of Sciences,Beijing 100101 5Department of Physiology,Health Science center,peking {4.,Beijing 100083.{14. Institute of Cardiovascular Diseases the First Hospital Peking University Institute of Cardiovascular Diseases Peking University Institute of Biophysics Chinese Academy of Sciences Beijing 100101 Department of Physiology Health Science Center Pe

AIM: To observe protective effects of taurine on reactive oxygen species generation induced by homocysteine in rat vascular smooth muscle cells (VSMC). METHODS: Rat VSMC was incubated with various concentrations of homocysteine and taurine. The lactate dehydrogenase (LDH) activity which released into culture medium was elevated as an indicator for VSMC injury. The reactive oxygen species (ROS) — hydrogen peroxide (H2O2) and superoxide anion (O2ˉ· )were measured with luminol or lucigenin chemiluminescences method, and the mitochondria Mn-superoxide dismutase (Mn-SOD) and catalase (CAT) were also measured in treated VSMC. RESULTS: LDH leakage from cultured VSMC treated with homocystenie, was increased (P0.05 vs control). In this study, the superoxide anion in VSMC was not detectable by chemiluminent method. In addition, treatment of VSMC with taurine increased mitochondria Mn-SOD and CAT activity in a concentration dependent manner (P<0.05), but homocysteine decreased mitochondria Mn-SOD and CAT activity (P<0.01 vs control). In addition, co-administration of taurine markedly ameliorated homocysteine-induced inhibition of Mn-SOD and CAT activity in VSMC (P<0.01 vs homocysteine alone group). CONCLUSION: Taurine antagonized the effects of homocysteine on ROS generation and anti-oxidant enzyme activities in rat VSMC in vitro.

关键词： homocysteine taurine vascular smooth muscle mitochondria reactive oxygen species

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A method for blind separation of components information from mixed pixel

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Progress in Natural Science:Materials International 2006年第7期16卷 760-765页

作者： FAN Wenjie and XU Xiru ( Institute of Remote Sensing and Geographical information System, peking university, Beijing 100871,{3. {4. of Remote Sensing and GIS of Beijing Normal university, Beijing 100875,{3.) peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China Beijing Normal Univ Ctr Remote Sensing & GIS Beijing 100875 Peoples R China

In the field of remote sensing, it is important to separate the component information from mixed pixel. If the physical process of remote sensing can be expressed by a set of linear equations, the remote sensing information matrix is equal to the weight matrix multiplied by the component information matrix. Generally speaking, the precondition of retrieval of component information matrix is that the weight matrix is known. However, the blind signal separation (BSS) method can separate the matrix unconditionally, whose basic principle is that the additive information needing separation can be achieved from the statistical characteristics contained in a mass of samples in the remotely sensed information matrix. Therefore, the values of the component information matrix and the weight matrix can be estimated. The wave shape of components can be retrieved by BSS, but the amplitude cannot. In this paper, the plant-soil mixed pixels were chosen as the studying targets in this paper to quantitatively separate the component information and solve the uncertainty of BSS. Simulation and field test verify the reliability of the method. Results show that the BSS can be one of the effective methods of mixed pixel separation, and the foreground of application is very promising.

关键词： mixed pixel component information blind signal separation.

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Calculation of traversal time in tunneling by double-wave theory

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Chinese Science Bulletin 1998年第9期43卷 723-727页

作者： HUANG Xiangyou Department of Physics, peking university, Beijing 100871, china Department of Physis Peking University Beijing China

Becausethe information contained in a wave function is not enough to describe an individual particle, the suggestion to define the state of a particle by two-wave functions is used. In the double-wave description, a general formula telling the traversal time of a particle in tunneling is obtained. When the double-wave description over an initial parameter is averaged , it reduces to the usual description. Two new relations between the transmission and the reflected coefficients are founded in the new cescription.

关键词： tunneling double-wave theory ensemble.

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A stochastic method for convective storm identification,tracking and nowcasting

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Progress in Natural Science:Materials International 2008年第12期18卷 1557-1563页

作者： Lei Han~(a,b) Shengxue Fu~a Guang Yang~c Hongqing Wang~b Yongguang Zheng~d Yingjing Lin~b a College of information Science and Engineering.Ocean university of china,Qingdao 266101,{3. b Department of Atmospheric Science,{4. university,Beijing 100871,{3. c Department of Probability and Statistics,{4. university,Beijing 100871,{3. d National Meteorological center,Beijing 100081,{3. College of information Science and Engineering Ocean University of China Qingdao 266101 China Department of Atmospheric Science Peking University Beijing 100871 China Department of Probability and Statistics Peking University Beijing 100871 China National Meteorological center Beijing 100081 China

The convective storm identification,tracking and nowcasting method is one of the important nowcasting methodologies against severe convective *** severe convective cases,such as storm shape or rapid velocity changes,existing methods are apt to provide unsatisfied storm identification,tracking and nowcasting *** overcome these difficulties,this paper proposes a novel approach to identify,track and short-term forecast (nowcast) of convective storms.A mathematical morphology-based storm identification method is adopted which can identify storm cells accurately in a cluster of *** for the difficult tracking problem,sequential Monte Carlo (SMC) method is utilized to simplify the tracking *** is not only inherently suitable for handling complicated splits and mergers, but also capable of handling the case of storm-missing *** order to provide more accurate forecast of a storm position,this method takes the advantages of the cross-correlation *** qualitative and quantitative evaluations show the efficiency and robustness of the proposed approach.

关键词： Convective storm Doppler radar Nowcasting

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The Existence of Global Solution for a Class of Semilinear Equations on Heisenberg Group

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Chinese Quarterly Journal of Mathematics 2004年第4期19卷 426-435页

作者： ZHENG Zhu-jun, WANG Guo-an, LU Ke-ping,LUO Xue-bo(1. College of Mathematics and information Science, Henan university, Kaifeng 4.5001, china 2.Institute of Mathematics, Henan university, Kaifeng 4.5001, china 3. information Network center, Henan university, Kaifeng 4.5001, china 4. Institute of Applied Mathematics, Northwestern Ploytechnical university, Xi'an 710072, china) college of Mathematics and information Science Henan University Kaifeng 475001china institute of Mathematics Henan University Kaifeng 475001china information Network center Henan University Kaifeng 475001china college of Mathematics and information Science Henan University Kaifeng 475001china Institute of Applied Mathematics Northwestern Ploytechnical University Xi'an 710072 china

Based on the concepts of a generalized critical point and the corresponding generalized P.S. condition introduced by Duong Minh Duc [1], we have proved a new Z2 index theorem and get a result on multiplicity of generalized critical points. Using the result and a quite standard variational method, it is found that the equation-ΔHnu = |u|p-1u,x∈Hnhas infinite positive solutions. Our approach can also be applied to study more general nonlinear problems.

关键词： subelliptic operator Z2 index Heisenberg group generalized critical point

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Quick image-processing method of UAV without control points data in earthquake disaster area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 523-528页

作者： LI Chang-chun1, ZHANG Guang-sheng1, LEI Tian-jie2, 3. GONG A-du2, 3.1. School of Surveying & Land information Engineering, Henan Polytechnic university, Jiaozuo 4.4.00,{4. 2. Key Laboratory of Environmental Change and Natural Disaster, Ministry of Education, Beijing Normal university, Beijing 100875,{4. 3. Ministry of Civil Affairs/Ministry of Education of{4. Academy of Disaster Reduction and Emergency Management, Beijing Normal university, Beijing 100875,{4. School of Surveying & Land information Engineering Henan Polytechnic University Jiaozuo 454000 China Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China Ministry of Civil Affairs/Ministry of Education of china Academy of Disaster Reduction and Emergency Management Beijing Normal University Beijing 100875 China

The methods of unmanned aerial vehicles images splicing rapidly and rectifying without control points data, only using auxiliary data recorded by unmanned aerial vehicle (UAV) system, were researched. Two algorithms were proposed, including UAV images auto- splicing rapidly after image blocking and UAV images rectifying based on pseudo center points of auxiliary data. When SIFT algorithm for UAV images splicing is applied, the accuracy is very high, but the efficiency is very low. The splicing efficiency is improved greatly based on SIFT algorithm after image blocking. The results show that rectifying accuracy is very high and has no visual dislocation when pseudo center points of auxiliary data is applied.

关键词： unmanned aerial vehicles SIFT algorithm blocking quickly splicing rectification

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Architecture and key technologies of grid geographic information system

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Science china(Technological Sciences) 2008年第S1期51卷 102-113页

作者： FANG Yu,HUANG Zhou,CHEN Bin,WU Lun & YIN DaFei Institute of Remote Sensing and Geographic information System,peking university,Beijing {3.,{4. Institute of Remote Sensing and Geographic information System Peking University

The highly efficient and stable collaborative computation platform for geospatial information can be constructed on the basis of Grid computing technology,com-bined with Peer-to-Peer (P2P) computing technology and geospatial database technology. This paper proposed the architecture and key technologies of the Grid GIS (Geographic information System) incorporated with P2P structure,and corre-spondingly a Grid GIS prototype named Nebula was designed and then imple-mented. Nebula is a suite of middleware for geospatial Grid computing,which could be deployed onto various service nodes in network. Based on Grid protocols and infrastructure,Nebula provides invocation interfaces to users in form of Grid services. By using P2P message based communication mechanism,complex geospatial computation tasks could be accomplished by Nebula in a collaborative way. This paper introduced Nebula's architecture and key modules,and according to experimental data,we discussed the Grid GIS's advantages,application scenar-ios and future directions.

关键词： Grid GIS distributed geospatial computing Peer-to-Peer computing

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A common sense geographic knowledge base for GIR

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Science china(Technological Sciences) 2008年第S1期51卷 26-37页

作者： ZHANG Yi,GAO Yong,XUE LuLu,SHEN Si & CHEN KaiChen Institute of Remote Sensing and Geographic information System,peking university,Beijing {3.,{4. Institute of Remote Sensing and Geographic information System Peking University

As background knowledge of geographic information retrieval (GIR),the gazetteers have their limitations. In this paper we propose to develop and implement a com-mon sense geographic knowledge base (CSGKB) instead of the gazetteers. We define that CSGKB is concerned with the representation of geographic knowledge in human brain and the simulation of geographic reasoning in daily life. Traditional geographic information system (GIS) is based on the model of map with its data based on geographic coordinates and its computation based on geometry. However,CSGKB,which is made up of geographic features and relationships and is based on qualitative spatio-temporal reasoning,can be viewed as the direct model of geographic world. This paper also discusses the characters of CSGKB and pre-sents its structure which is composed of knowledge base,inference engine,geo-graphic ontology and learner. The applications using CSGKB include geographic information retrieval (GIR),natural language processing (NLP),named entity rec-ognition (NER),Semantic Web,etc. At present,our work focuses on the design of geographic ontology and the implementation of the CSGKB knowledge base. In this paper we describe the CSGKB ontology structure,top ontology,geographic loca-tion ontology,spatial relationship ontology,and domain ontologies. Finally,we in-troduce the current state of implementation of CSGKB and give an outlook on our future researches.

关键词： geographic information retrieval common sense geographic knowledge base geographic ontology

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