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Advanced fluid-typing methods for NMR logging

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Petroleum Science 2011年第2期8卷 163-169页

作者： Xie Ranhong Xiao Lizhi state key laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China key laboratory of Earth Prospecting and information Technology China University of Petroleum Beijing 102249 China

In recent years, nuclear magnetic resonance （NMR） has been increasingly used for fluid- typing in well-logging because of the improved generations of NMR logging tools. This paper first discusses the applicable conditions of two one-dimensional NMR methods： the dual TW method and dual TE method. Then, the two-dimensional （T2, D） and （T2, T1） NMR methods are introduced. These different typing methods for hydrocarbon are compared and analyzed by numerical simulation. The results show that the dual TW method is not suitable for identifying a macroporous water layer. The dual TE method is not suitable for typing gas and irreducible water. （T2, T1） method is more effective in typing a gas layer. In an oil-bearing layer of movable water containing big pores, （T2, T1） method can solve the misinterpretation problem in the dual TWmethod between a water layer with big pores and an oil layer. The （T2, T1） method can distinguish irreducible water from oil of a medium viscosity, and the viscosity range of oil becomes wide in contrast with that of the dual TW method. The （T2, D） method is more effective in typing oil and water layers. In a gas layer, when the SNR is higher than a threshold, the （T2, D） method can resolve the overlapping T2 signals of irreducible water and gas that occurs due to the use of the dual TE method. Twodimensional NMR for fluid-typing is an important development of well logging technology.

关键词： NMR logging one-dimensional NMR two-dimensional NMR reservoir evaluation fluidtyping

Object oriented land cover classification using ALS and GeoEye imagery over mining 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 733-737页

作者： YU Hai-yang, CHEng Gang, GE Xiao-san, LU Xiao-ping key laboratory of Mine Spatial information Technologies of state Bureau of Surveying and Mapping, Henan Polytechnic University, Jiaozuo 454000, china key laboratory of Mine Spatial information Technologies of state Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454000 China

An object oriented coal mining land cover classification method based on semantically meaningful image segmentation and image combination of GeoEye imagery and airborne laser scanning (ALS) data was presented. First, DEM, DSM and nDSM (normalized Digital Surface Model, nDSM) were extracted from ALS data. The GeoEye imagery and DSM data were combined to create segmented objects based on neighbor regions merge method. Then 10 kinds of objects were extracted. Different kinds of vegetation objects, including crop, grass, shrub and tree, can be extracted by using NDVI and height value of nDSM. Water and coal pile field was extracted by using NDWI and the standard deviation of DSM method. Height differences also can be used to distinguish buildings from road and vacant land, and accurate building contour information can be extracted by using relationship of neighbor objects and morphological method. The test result shows that the total classification accuracy of the presented method is 90.78% and the kappa coefficient is 0.891 4.

关键词： airborne laser scanning GeoEye nDSM object oriented classification mining areas

Fuzzy entropy image segmentation based on particle swarm optimization

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Progress in Natural Science:Materials International 2008年第9期18卷 1167-1171页

作者： Linyi Li a, Deren Li b, a School of Remote Sensing and information Engineering, Wuhan University, Wuhan 430079, china b state key laboratory of information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, Wuhan 430079, china School of Remote Sensing and information Engineering Wuhan University Wuhan 430079 China state key laboratory of information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China

Particle swarm optimization is a stochastic global optimization algorithm that is based on swarm *** of its excellent performance, particle swarm optimization is introduced into fuzzy entropy image segmentation to select the optimal fuzzy parameter combination and fuzzy threshold *** this study, the particles in the swarm are constructed and the swarm search strategy is proposed to meet the needs of the segmentation *** fuzzy entropy image segmentation based on particle swarm opti-mization is implemented and the proposed method obtains satisfactory results in the segmentation *** with the exhaustive search method, particle swarm optimization can give the same optimal fuzzy parameter combination and fuzzy threshold while needing less search time in the segmentation experiments and also has good search stability in the repeated ***, fuzzy entropy image segmentation based on particle swarm optimization is an eficient and promising segmentation method.

关键词： Image segmentation Fuzzy entropy Particle swarm optimization Fuzzy parameter combinations Fuzzy threshold

A prototype auto-human support system for spatial analysis

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Progress in Natural Science:Materials International 2006年第9期16卷 954-966页

作者： LI Lianfa and WAng Jinfeng (state key laboratory of Resources & Environmental information System, Institute of Geographical Sciences & Natural Resources Research, Chinese Academy of Sciences, beij.ng 100101, china) [a]state key laboratory of Resources & Environmental information System Institute of Geographical Sciences & Natural Resources Research Chinese Academy Sciences Beijing China

Spatial analysis is a multidisciplinary field that involves multiple influential factors, variation and uncertainty, and modeling of geospatial data is a complex procedure affected by spatial context, mechanism and assumptions. In order to make spatial modeling easier, some scholars have suggested a lot of knowledge from exploratory data analysis (EDA), specification of the model, fitness and diagnosis of the model, to interpretation of the model. Also an amount of software has improved some functionalities of spatial analysis, e. g. EDA by the dynamic link (GeoDa) and robust statistical calculation (R). However, there are few programs for spatial analysis that can automatically deal with unstructured declarative issues and uncertainty in machine modeling using the domain knowledge. Under this context, this paper suggests a prototype support system for spatial analysis that can automatically use experience and knowledge from the experts to deal with complexity and uncertainty in modeling. The knowledge base component, as the major contribution of the system, in support of the expert system shell, codes and stores declarative modeling knowledge, e.g. spatial context, mechanisms and prior knowledge to deal with declarative issues during the modeling procedure. With the open architecture, the system integrates functionalities of other components, e.g. GIS’ visualization, DBMS, and robust calculation in an interactive environment. An application case of spatial sampling, design and implementation of spatial modeling with such a system is demonstrated.

关键词： spatial analysis automatic support system modeling of spatial data artificial inference for modeling.

Computational RNomics:Structure identification and functional prediction of non-coding RNAs in silico

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Science china(Life Sciences) 2010年第5期53卷 548-562页

作者： ZHEng LingLing & QU LiangHu key laboratory of Gene Engineering of the Ministry of Education,state key laboratory for Biocontrol,Sun Yat-sen University,Guangzhou 510275,china 1. key laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for Biocontrol Sun Yat-sen University Guangzhou 510275 China

The eukaryotic genome contains varying numbers of non-coding RNA(ncRNA) genes."Computational RNomics" takes a multidisciplinary approach,like information science,to resolve the structure and function of ***,we review the main issues in "Computational RNomics" of data storage and management,ncRNA gene identification and characterization,ncRNA target identification and functional prediction,and we summarize the main methods and current content of "computational RNomics".

关键词： non-coding RNA eukaryote computational RNomics

The characteristic properties of PEDOT nano-particle based on reversed micelle method

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Science china(Technological Sciences) 2010年第9期53卷 2355-2362页

作者： ZHEng HuaJing,JIAng YaDong,XU JianHua & YAng YaJie state key laboratory of Electronic Thin Films & Integrated Devices,School of Optoelectronic information,University of Electronic Science and Technology of china,Chengdu 610054,china 1. state key laboratory of Electronic Thin Films & Integrated Devices School of Optoelectronic Information University of Electronic Science and Technology of China Chengdu 610054 China

Based on the study of a new type of conducting polymer poly (3,4-ethylenedioxythiophene) (PEDOT),this paper focuses on the preparation and the materials properties of PEDOT nanoparticles made by reversed micelle *** on optical,electrical and the thermal stability of PEDOT nanoparticles were carried *** main results were as follows: The small-sized PEDOT nanoparticles were prepared by different methods,such as ultraviolet/visible (UV-Vis) spectroscopy,fourier-transform infrared (FT-IR) spectrum,scanning electron microscopy (SEM) and so *** Bragg peaks of nanoparticles at 6.7°,12.7°,25° were observed by XRD and the good orientation of molecular chain was attributed to the effective doping of toluene-p-sulfonic acid,which also resulted in an enhancement of thermal stability of nanoparticles compared with the conventional ***,the gas sensitivity of nanoparticles deposited on quartz crystal microbalance (QCM) was studied and the nanopartices deposited device exhibited excellent sensitivity to HCl gas at low *** sensitivity of the nanoparticles by the reverse micelle was better than that of the common PEDOT particles.

关键词： poly (3 4-ethylenedioxythiophene) conducting polymer reversed micelle n-particle photoelectric properties thermal stability

Level Set interface treatment and its application in Euler method

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Science china(Physics,Mechanics & Astronomy) 2010年第2期53卷 227-236页

作者： WU KaiTeng1,2,HAO Li3,WAng Cheng4 & ZHAng Li1,2 1 Numerical Simulation Sichuan Higher School key laboratory,Neijiang Normal University,Neijiang 641112,china 2 College of Mathematics and information Science,Neijiang Normal University,Neijiang 641112,china 3 College of Science,beij.ng University of Civil Engineering and Architecture,beij.ng 100044,china 4 state key laboratory of Explosion Science and Technology,beij.ng Institute of Technology,beij.ng 100081,china 1. Numerical Simulation Sichuan Higher School key laboratory Neijiang Normal University Neijiang 641112 China2. College of Mathematics and Information Science Neijiang Normal University Neijiang 641112 China3. College of Science Beijing University of Civil Engineering and Architecture Beijing 100044 China4. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China

Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3D programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method.

关键词： Euler method Level Set method shock-wave action on bubble implosion numerical simulation

tRNAs as regulators in gene expression

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Science china(Life Sciences) 2009年第3期52卷 245-252页

作者： LI Yan & ZHOU Hui key laboratory of Gene Engineering of the Ministry of Education,state key laboratory for Biocontrol,Sun Yan-Sen University Guangzhou 510275,china 1. key laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for Biocontrol Sun Yan-Sen University Guangzhou 510275 China

Transfer RNAs(tRNAs) hold a central place in protein synthesis by interpreting the genetic information stored in DNA into the amino acid sequence of protein,thus functioning as "adaptor" *** recent years,however,various studies have shown that tRNAs have additional functions beyond participating in protein *** suffering from certain nutritional stresses,tRNAs change the level of aminoacylation to became uncharged,and these uncharged tRNAs act as effector molecules to regulate global gene expression,so that the stressed organism copes with the adverse environmental *** budding yeast and certain mammalian cells,the retrograde movement of mature tRNAs from cytoplasm to nucleus serves as a mechanism for the surveillance system within the nucleus to continue monitoring the integrity of *** the other hand,this retrograde action effectively reduces the global protein synthesis level under conditions of nutritional *** recently,various publications have shown that tRNAs are not stable molecules in an absolute *** certain physiological or environmental stresses,they are specifically cleaved into fragments of different lengths in the anticodon loop or anticodon left *** cleavages are not a meaningless random degradation ***,a novel class of signal molecules such as tRNA halves or sitRNAs may be produced,which are closely correlated with the modulation of global gene *** of the regulatory functions of tRNAs is a frontier,which seeks to reveal the structural and functional diversity of tRNAs as well as their vital functions during the expression of genetic information.

关键词： tRNA sitRNA gene expression regulation stress response

Data acquisition and simulation of natural phenomena

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Science china(information Sciences) 2011年第4期54卷 683-716页

作者： ZHAO QinPing state key laboratory of Virtual Reality Technology and Systems,Beihang University,beij.ng 100191,china 1. state key laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China

Virtual natural phenomena obtained through mathematical-physical modeling and simulation as well as graphics emulation can meet the user’s requirements for sensory experiences to a certain extent but they can hardly have the same accurate physical consistency as real natural *** technology for data acquisition and natural phenomena simulation can enable us to obtain multi-dimensional and multi-modal data directly from real natural phenomena and,based on these real data,to establish digital models highly consistent with real natural phenomena in appearance,physics,behavior or many other aspects,thus making a virtual natural phenomenon a direct mapping of real natural *** approach is conducive to resolving problems concerning the reliability and availability of virtual *** present the technology for acquiring and simulating dada of natural phenomena is still in its initial *** paper gives a review of the related ***,we briefly introduce the basic methods and techniques concerned,then,based on the difference between the basic elements of various natural phenomena,we discuss the current studies on such natural phenomena as light,water,fire,smoke,dynamic terrain,etc.,and finally,in connection with issues in the present research and possible future direction of development,we put forth a number of theoretical and technical problems,hoping they can be resolved in the near future.

关键词： natural phenomena data acquisition simulation data driven reliability