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Study on attribute characterization for reservoir dynamic monitoring by seismic

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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 {2.,Beijing 102.49,china 2.Basin & Reservoir Research Center,china Petroleum {2.,Beijing 102.49,china 3 state key laboratory of Petroleum Resource and Prospecting,china {2. of Petroleum,Beijing 102.49,china 4 Research Center of CNOOC,Beijing 10002.,china key Lab of Geophysical Exploration of CNPC China Petroleum University Beijing China state key {2. 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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用电容传感器进行相对测量的实验装置设计

实验技术与管理 2010年第1期27卷 50-53页

作者：孙长库肖旭王鹏天津大学精密测试技术及仪器国家重点实验室

电容测量技术具有非接触、稳定性好、测量微位移时具有高分辨率等特点,广泛应用于缓慢变化和微小位移的非接触测量。设计了一套用于教学的电容传感器进行相对测量的实验装置,系统介绍了电容传感器进行相对测量的原理及电路,给出了电容... 详细信息

电容测量技术具有非接触、稳定性好、测量微位移时具有高分辨率等特点,广泛应用于缓慢变化和微小位移的非接触测量。设计了一套用于教学的电容传感器进行相对测量的实验装置,系统介绍了电容传感器进行相对测量的原理及电路,给出了电容传感器的标定方法,并进行了标定实验。设计了容易操作的传感器现场标定和相对测量的软件。该装置旨在帮助学生深入理解电容传感器的工作原理、相对测量概念、仪器标定及数据处理方法。

关键词：电容传感器相对测量标定

Relations between thickness of UHMWPE’s wear debris and positive pressure of tribological system

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Chinese Science Bulletin 2008年第9期53卷 1435-1443页

作者： LIU HongTao1,2.3 & GE ShiRong1,3 1 Institute of Tribology and Reliability Engineering, china university of Mining & Technology, Xuzhou 2.1116, china 2.College of Mechanical and Electrical Engineering, china university of Mining & Technology, Xuzhou 2.1116, china 3 Biotribology Center, state key laboratory of Tribology, Xuzhou 2.1116, china Institute of Tribology and Reliability Engineering China University of Mining & Technology Xuzhou China College of Mechanical and Electrical Engineering China University of Mining & Technology Xuzhou China Biotribology Center State Key Laboratory of Tribology Xuzhou China

MiaoXAM2.5X-50X Ultrahigh precision Surface 3D Profiler is introduced to research the relations be- tween thickness of UHMWPE’s wear debris and positive pressure of tribological system. Research re- sults show that thickness of wear debris owns evident classification, and the first grade thickness math model and the second grade thickness math model are built. By the second grade thickness math model, the true force condition in the tribological system can be gotten, and the model can be used as a tool to modify simulating parameters of the tribological system, and it is an important inspecting method to the airtight system which cannot be examined in real time. The first grade thickness math model can describe the true working load and surface condition of work piece in the tribological sys- tem, and is an effective description method for the running condition of frictional pairs. The research results at different lubricating conditions testify the relations between thicknesses of wear debris and positive pressure of the tribological system. The fractal relation between maximal thickness of wear debris and positive pressure is discussed. The conceptions of the immutability principle and charac- teristic granularity of wear debris thickness are brought forward and discussed. In conclusion, as a stable tribological parameter owning mechanical theory basis, wear debris thickness will play an im- portant part in fault diagnosis, especially for the airtight system such as artificial joint.

关键词：摩擦学磨损面厚度分形数学模型

Unsteady-state Grinding Technology (I) Theoretical Generalization and Research on Grinding Mechanism

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厦门大学学报（自然科学版） 2002年第S1期41卷 46-47页

作者： LIN Bin, LI Zhi-chao, XU Yan-shen, HU Jun (The state Education Ministry key {2. of High Temperature Structure Ceramics and Machining Technology of Engineering Ceramics, tianjin university, tianjin 3.0072, china)

In conventional grinding theory, it is obvious that there must be a very high hardness difference between grains of the grinding wheel and workpieces. The best grinding wheels are those giving the lowest "natural limiting surface roughness" while cutting at appreciable plunge velocities. With the development of new materials and new machining processes, conventional theories of grinding techniques are no longer suitable to explain many phenomena in the course of grinding procedures. In dealing with precision or ultra-precision grinding processes of advanced ceramics, many results of experiments and practical production have shown that grinding with super hard materials wheels is not the only method to machine advanced ceramics. This paper is intended to propose a new grinding theory named as unsteady-{2. grinding technique evolved from some phenomena that can not be explained by conventional grinding theory. Unsteady-{2. grinding technique means the technique which can make the surface roughness of the materials, especially hard and brittle, be up to the standard of ultra-precision machining by utilizing common wheels characteristic of inferior self-sharpening and wear-resistance. In the process of machining, the common wheel need to be redressed about 3～5 times and the time between two redressings is about 3～5 minutes. As a validation of the new grinding technology, experimental work was performed to prove the existence of the unsteady {2. in the process of ultra-precision grinding with common abrasive wheel-pink fused alumina wheel. From the results of the observation of the wheel topography, the whole grinding process in unsteady {2. was separated into three stages namely cutting by grains peaks, micro-cutting by micro edges of the broken grains and rubbing without material removal, which is different from conventional grinding theory. For the difference of hardness between grinding wheel and workpiece material is not so apparent, some people have doubts

关键词： unsteady state grinding theory grinding mechanism common abrasive wheel ceramic

Unsteady-state Grinding Technology (III) Studies on the Surface Quality

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厦门大学学报（自然科学版） 2002年第S1期41卷 42-43页

作者： XU Yan-shen, HU Jun, LIN Bin, LI Zhi-chao (The state Education Ministry key {2. of High Temperature Structure Ceramics and Machining Technology of Engineering Ceramics, tianjin university, tianjin 3.0072, china)

In conventional grinding theory, the chief removed mode of ceramic coprocessor by diamond tools was brittle removal. In order to perform the plastic removal or ductility processing of engineering ceramics the high degree of accuracy and high rigidity grinner must be using micro grain size diamond grinding wheel to direct the processing of micron below rank depth to prevent form the occurring of the brittle processing zone. This will resulted in the high expense of grinding. The expense of grinding could even reach the 80% of the total manufacture cost of the ceramic part. Ultra-precision grinding for advanced ceramics has been achieved by the unsteady-state grinding technique. In this paper, we mainly deals with observing and analyzing the surface quality of the silicon nitride ground by pink fused alumina wheel in different grinding parameters. To optimize the grinding parameters in the process of the unsteady-state grinding, the experiments of X-ray diffraction, energy spectrum analysis, SEM observation and roughness measurement were performed. The results show that: 1. In the process of unsteady state grinding, high line speed (rotational speed) of the grind wheel can improve the roughness of the silicon nitride apparently. It was also evident that the larger the grain mesh size, the better the surface quality. 2. There exists an optimum combination of grinding conditions such as grinding wheel speed, rotational speed of the workpiece, feed rate between the grinding wheel and the workpiece, grinding times and cutting coolant. The surface quality of the silicon nitride can be up to the standard of mirror finishing. 3. By analyzing the finished surface with X-ray diffraction and energy spectrum, the existence of some new phases including titanium and alumina was proved. 4. By utilizing the unsteady state grinding technique, the surface roughness of Ra ≤ 0.030 μm can be achieved by grinding the silicon nitride with the pink fused alumina wheel in low cost. Based on

关键词： unsteady state grinding theory engineering ceramics grinding surface quality

Dependence Analysis Based on Dynamic Slicing for Debugging

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 398-404页

作者： Chen Zhen qiang 1, Xu Bao wen 1,2.1 Department of Computer Science & Engineering, Southeast university, Nanjing 2.0096, china 2.{2. key laboratory of Software Engineering, Wuhan university, Wuhan 430072. china Department of Computer Science & Engineering Southeast University Nanjing China state key {2. of Software Engineering Wuhan University Wuhan China

Dynamic program slicing is an effective technique for narrowing the errors to the relevant parts of a program when debugging. Given a slicing criterion, the dynamic slice contains only those statements that actually affect the variables in the slicing criterion. This paper proposes a dynamic slicing method based on static dependence analysis. It uses the program dependence graph and other static information to reduce the information needed to be traced during program execution. Thus, the efficiency is dramatically improved while the precision is not depressed. The slicing criterion is modified to fit for debugging. It consists of file name and the line number at which the statement is.

关键词： program slice slicing criterion program dependence graph

Satellite-based RAR performance simulation for measuring directional ocean wave spectrum based on SAR inversion spectrum

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Acta Oceanologica Sinica 2010年第4期29卷 13-20页

作者： REN Lin MAO Zhihua HUANG Haiqing GONG Fang Department of Electromagnetic Fields and Microwave Theory Nanjing University of Science and Technology Nanjing 210094 China state key {2. of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

Some missions have been carried out to measure wave directional spectrum by synthetic aperture radar （SAR） and airborne real aperture radar （RAR） at a low *** them have their own advantages and *** hope that SAR and satellite-based RAR can complement each other for the research on wave properties in the *** this study,the authors aim to simulate the satellite-based RAR system to validate performance for measuring the directional wave *** principal measurements are introduced and the simulation methods based on the one developed by Hauser are adopted and slightly *** enhance the authenticity of input spectrum and the wave spectrum measuring consistency for SAR and satellite-based RAR,the wave height spectrum inversed from Envisat ASAR data by cross spectrum technology is used as the input spectrum of the simulation *** the process of simulation,the sea surface,backscattering signal,modulation spectrum and the estimated wave height spectrum are simulated in each look *** wave spectrum are measured based on the simulated observations from 0 ？ to 360 ？ .From the estimated wave spectrum,it has an 180 ？ ambiguity like SAR,but it has no special high wave number cut off in all the ***,the estimated spectrum is compared with the input one in terms of the dominant wave wavelength,direction and SWH and the results are *** simulation shows that satellite-based RAR should be capable of measuring the directional wave ***,it indicates satellite-based RAR basically can measure waves that SAR can measure.

关键词： satellite-based RAR directional wave spectrum SAR inversion performance simulation

Thermodynamic Analysis on Interaction between Molten Ti Alloys and Oxide Molding Materials

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Journal of Materials Science & Technology 2001年第1期17卷 99-100页

作者： Hongsheng DING Jun JIA Jingiie GUO and Yanqing SU National key laboratory of {2. Hot Processing of Metals, Harbin 150001, china HengZhi FU and Jinshan LI state key laboratory of Solidification Processing, Northwestern Polytechnical university, Xi’ Harbin Inst. of Technol. Harbin 150001 China

A thermodynamic model has been built up for the interactions between molten Ti alloys and oxide molding materials in the way of decomposition and solution of molding materials, then the influences on the reaction free... 详细信息

关键词： Ti Thermodynamic Analysis on Interaction between Molten Ti Alloys and Oxide Molding Materials

Suppression of Sidelobe for Acousto-Optic Tunable Filter in Near-Infrared Spectral Monitoring

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光学学报 2003年第S1期23卷 827-828页

作者： Fan Guo-fang ,Yang Ji-sheng,Sang Wei, Xu Ke-xinDepartment of Applied Physics, state key {2. of precision Technology and instruments, tianjin university.P.R.china, Tel:86-2.-2.402.84,Fax:86-2.-2.890681 ,E-mail:fgf78@*** Department of Applied Physics Tianjin UniversityP.R.China state key {2. of precision Technology and instruments Tianjin UniversityP.R.China

In this paper we calculated the acoustic intensity distribution of different transducers, and designed acousto-optic tunable filter(AOTF) based on different transducers. Through the experiment, we find sidelobe can be... 详细信息

关键词： AOTF on be for of in