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Study on forward modeling of through-casing resistivity logging

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Science china Earth Sciences 2008年第S2期51卷 207-211页

作者： GAO Jie1,LIU FuPing2,BAO DeZhou3,CHENG Xi3 & ZHANG YuLing4 1 china University of Petroleum,beijing 102249,china 2 beijing Institute of Graphic Communication,beijing 102600,china 3 china Petroleum Logging CO. ltd.,Xi’an 710021,china 4 china National Logging Corporation,beijing 100101,china china University of Petroleum Beijing China beijing Institute of Graphic Communication Beijing China china Petroleum Logging CO. ltd. Xi’an China china National Logging Corporation Beijing China

Through-casing resistivity logging (TCRL) is a new kind of logging method for formation evaluation,reservoir monitoring and saturation changes tracking. In this paper,the basic principle of TCRL is de-tailed,and the modified transmission line equation method (MTLEM) is first proposed in china. The MTLEM has been employed to simulate the responses of TCRL,on the basis of which,the effects of formation resistivity,cement and casing on the responses of TCRL are analyzed,and the signals in-duced in different formations are also calculated,which can help the design of TCRL tool and data processing and interpretation in china.

关键词： through-casing resistivity logging (TCRL) modified transmission line equation method (MTLEM) casing cement sheath

STUDY ON THE SYNTHESIS AND PROPERTIES OF POLY(ESTER-IMIDEETHER)MULTIBLOCK COPOLYMERS

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Chinese Journal of Polymer Science 2000年第1期18卷 9-13页

作者： Zu-yao Shan Zhen-yi Li Institute of Chemistry, Chinese Academy of Sciences, beijing 100080, china 中科院化学所北京

A new class of poly(ester-imide-ether) multiblock copolymers was synthesized by transes-terification and melt copolymerization of dimethyl terephthalate (DMT) and N-(4-carbomethoxyphenyl)-4-(carbomethoxy)-phthalimide with ethylene glycol (EG) and polytetramethylene glycol (PTMG). The structure of the above copolymers was characterized by H-1-NMR and IR spectroscopy. Some properties of the coplymers were also examined. It was found that their mechanical properties and heat stability, compared with poly(ether-ester) copolymers, were obviously improved.

关键词： N-(4-carbomethoxyphenyl)-4-(carbomethoxy)-phthalimide polyester-polyether copolymer poly-(ester-imidether) multiblock copolymer imide modification

THE DUAL MIXED METHOD FOR AN UNILATERAL PROBLEM

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Journal of Computational Mathematics 2003年第6期21卷 733-746页

作者： Lie-heng Wang(LSEC, ICMSEC, Academy of Mathematics and System Sciences, Chinese Academy of Sciences,beijing 100080, china) LSEC ICMSEC Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

In this paper, the dual mixed method for an unilateral problem, which is the simplified modelling of scalar function for the friction-free contact problem, is considered. The dual mixed problem is introduced, the existence and uniqeness of the solution of the problem are presented, and error bounds O(h3/4) and O(h3/2) are obtained for the dual mixed finite element approximations of Raviart-Thomas elements for k = 0 and k = 1 respectively.

关键词： Dual Mixed Method Unilateral Problem.

MATHEMATICAL ANALYSIS FOR QUADRILATERAL ROTATED Q_1 ELEMENT Ⅲ: THE EFFECT OF NUMERICAL INTEGRATION

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Journal of Computational Mathematics 2003年第3期21卷 287-294页

作者： Ping-bing Ming Zhong-ci Shi (Institute of Computational Mathematics, Chinese Academy of Sciences, beijing 100080, china) Institute of Computational Mathematics Chinese Academy of Sciences 北京 100080

This is the third part of the paper for the rotated Q1 nonconforming element on quadrilateral meshes for general second order elliptic problems. Some optimal numerical formulas are presented and analyzed. The novelty is that it includes a formula with only two sampling points which excludes even a Q1 unisolvent set. It is the optimal numerical integration formula over a quadrilateral mesh with least sampling points up to now.

关键词： Quadrilateral rotated Q1 element Numerical quadrature.

Cyclic Heating-Annealing and Boltzmann Distribution of Free Energies in a Spin-Glass System

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Communications in Theoretical Physics 2007年第7期48卷 179-182页

作者： ZHOU Hai-Jun Institute of Theoretical Physics,the Chinese Academy of Sciences,beijing 100080,china Institute of Theoretical Physics the Chinese Academy of Sciences Beijing 100080 China

Ergodicity of a spin-glass is broken at low temperatures;the system is trapped in one of many ergodicconfigurational *** between different ergodic domains are achievable through a *** this experiment is repeated infinite times,all ergodic configurational domains will be visited with frequencesthat decreasing exponentially with their free *** mean free energy density of a spin-glass system on a randomgraph is calculated based on this free energy Boltzmann distribution in the present work,by means of the cavity approach.

关键词： spin-glass ergodicity-broken cavity method

Scheme construction with numerical flux residual correction (NFRC) and group velocity control (GVC)

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Progress in Natural Science:Materials International 2006年第12期16卷 1252-1259页

作者： MA Yanwen **and FU Dexun(LNM, Institute of Mechanics, Chinese Academy of Sciences, beijing 100080, china) LNM Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

For simulating multi-scale complex flow fields like turbulent flows, the high order accurate schemes are preferred. In this paper, a scheme construction with numerical flux residual correction (NFRC) is presented. Any order accurate difference approximation can be obtained with the NFRC. To improve the resolution of the shock, the constructed schemes are modified with group velocity control (GVC) and weighted group velocity control (WGVC). The method of scheme construction is simple, and it is used to solve practical problems.

关键词： high order accurate scheme group velocity control high resolution of the shock.

CONVERGENCE OF NONLINEAR CONJUGATE GRADIENT METHODS

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Journal of Computational Mathematics 2001年第5期19卷 539-548页

作者： Yu-hong Dai (LSEC, ICMSEC, Academy of Mathematics and Systems Sciences, Chinese Academy of Sciences,beijing 100080, china) 中科院计算数学与科学工程计算所北京 100080

Presents a study on methods for unconstrained optimization. Assumptions of the study; Main results; Convergence properties of the methods under simplified Armijo-type line search.

关键词： unconstrained optimization conjugate gradient (generalized) line search global convergence

OPTIMAL MIXED H-P FINITE ELEMENT METHODS FOR STOKES AND NON-NEWTONIAN FLOW

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Journal of Computational Mathematics 2001年第1期19卷 67-76页

作者： Ping-bing Ming Zhong-ci Shi (Institute of Computational Mathematics, Chinese Academy of Sciences, beijing 100080, china) 中科院计算数学与工程计算数学所北京 100080

Presents an h -- p finite element methods based upon a mixed variational formulation for the three-field Stokes equations and linearized Non-Newtonian flow. Computation of the algebraic system generated from Problem H... 详细信息

关键词： mixed hp- finite element method non-Newtonian flow stabilization scaled weak B-Binequality

Study on Dynamical Behavior of Turbulent Premixed V-flames

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Journal of Thermal Science 2003年第4期12卷 381-384页

作者： Baorui Wang Kun Yuan Xiaoqian ZhangInstitute of Engineering Thermophysics, Chinese Academy of Sciences, beijing 100080, china Institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China

Differential interference contrast method was applied to investigate the flickering characteristics of V-flame in terms of both temporal and spatial scales. The flow characteristics of incident premixed combustibles were measured by means of laser Doppler anemometry (LDA). The characteristics of wake flow behind the stabilizing rod were obtained with numerical simulation. While the integral temporal scale of incident turbulence is about 1ms, the integral spatial scale about 2 mm, the characteristic flickering time scale is about 83 ms and spatial scale about 10 mm. The flame flickering frequency is more than 12 Hz, does not comply with the wake vortex shedding frequency, which is about 110 Hz. It is well-known that the flickering of V-flame is affected by both the incident turbulence and the wake flow after the stabilizing rod, but the result of the paper shows that the relationship between flickering characteristics and flow characteristics is much more complicated by the chemical reaction.

关键词： premixed flame turbulence numerical simulation.