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Fracture identification and evaluation using conventional logs in tight sandstones:A case study in the Ordos Basin,China

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Energy Geoscience 2020年第3期1卷 115-123页

作者： Shaoqun Dong Lianbo Zeng Wenya Lyu Dongling Xia Guoping Liu Yue Wu Xiangyi Du State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing102249China College of Science China University of PetroleumBeijing102249China College of Geoscience China University of PetroleumBeijing102249China Petroleum exploration and Production research institute SINOPECBeijing100083China

Fractures are of great significance to tight oil and gas *** identification using conventional well logs is a feasible way to locate the underground fractures in tight ***,there are three problems affecting its interpretation accuracy and practical application,namely weak well log responses of fractures,a lack of specific logs for fracture prediction,and relative change omission in log *** overcome these problems and improve fracture identification accuracy,a fracture indicating parameter(FIP)method composed of a comprehensive index method(CIM)and a comprehensive fractal method(CFM)is *** CIM tries to handle the first problem by amplifying log responses of *** CFM addresses the third one using fractal *** flexible weight parameters corresponding to logs in the CIM and CFM make the interpretation possible for wells lacking specific *** reconstructed logs in the CIM and CFM try to solve the second *** is noted that the FIP method can calculate the probability of fracture development at a certain depth,but cannot show the fracture development degree of a new well compared with other *** this study,a formation fracture intensity(FFI)method is also introduced to further evaluate fracture development combined with production *** test the validity of the FIP and FFI methods,fracture identification experiments are implemented in a tight reservoir in the Ordos *** results are consistent with the data of rock core observation and production,indicating the proposed methods are effective for fracture identification and evaluation.

关键词： Fracture identification Fracture evaluation Conventional well log Tight sandstone Ordos basin

Variations in the Summer Monsoon Rainbands Across Eastern China over the Past 300 Years

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Advances in Atmospheric Sciences 2009年第4期26卷 614-620页

作者：郝志新郑景云葛全胜 institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences

Based on reconstructions of precipitation events from the rain and snowfall archives of the Qing Dynasty （1736-1911）, the drought/flood index data mainly derived from Chinese local gazettes from 1736-2000, and the observational data gathered since 1951, the spatial patterns of monsoon rainbands are analyzed at different time scales. Findings indicate that monsoon rainfall in northern China and the middle-lower reaches of the Yangtze River have significant inter-annual （e.g., 5-7-yr and 2-4-yr） as well as inter-decadal （e.g., 20-30-yr and quasi-10-yr） fluctuation signals. The spatial patterns in these areas also show significant cycles, such as on a 60-80-yr time scale, a reversal phase predominates the entire period from 1736-2000; on a quasi-30-yr time scale, a consistent phase was prevalent from 1736 to 2000; and on a 20-yr time scale, the summer monsoon rains show different spatial patterns before and after 1870.

关键词： long-term variations monsoon rainbands historical documents China

Intermediate energy light sources and the SSRF project

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Nuclear Science and Techniques 2003年第1期14卷 1-8页

作者： ZHAO Zhen-Tang(Shanghai institute of Nuclear research, the Chinese Academy of Sciences, Shanghai 201800) Shanghai institute of Nuclear research the Chinese Academy of Sciences 上海 201800

Advances in insertion device technology, top-up operation and superconducting RF cavities make it possible to generate high brightness X-ray with intermediate energy light sources, which leads a new trend in designing and constructing third generation light sources around the world. The development status and the remarkable technical features of intermediate energy light sources are reviewed, and the main SSRF properties are described in this paper.

关键词：软X射线光源 SSRF 核技术上海同步辐射装置应用电子应用光束稳定性化学结构结构分析

A Theoretical Analysis of Interactive Coercing Effects Between Urbanization and Eco-environment

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Chinese Geographical Science 2013年第2期23卷 147-162页

作者： FANG Chuanglin WANG Jing institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences

Objectively, a complex interactive coercing relationship exists between urbanization and eco-environment, and the research of this relationship is primarily divided into three schools, i.e., interactive coercion theory, interactive promotion theory and coupling symbiosis theory. Harmonizing the relationship between urbanization and eco-environment is not only an important proposition for the national development plan but also the only way to promote healthy urbanization. Based on an analysis of urbanization process and its relationship with the eco-environment, this article analyzes interactive coercing effects between urbanization and eco-environment from three perspectives of population urbanization, economic urbanization and spatial urbanization, respectively, and analyzes risk effects of the interactive coercion. Further, it shows six basic laws followed by interactive coercion between urbanization and eco-environment, namely, coupling fission law, dynamic hierarchy law, stochastic fluctuation law, non-linear synergetic law, threshold value law and forewarning law, and divides the interactive coercing process into five stages, namely, low-level coordinate, antagonistic, break-in, ameliorative and high-grade coordinate. Based on the geometric derivation, the interactive coercing relationship between urbanization and eco-environment is judged to be non-linear and it can be explained by a double-exponential function formed by the combination of power and exponential functions. Then, the evolutionary types of the interactive coercing relationship are divided into nine ones: rudimentary coordinating, ecology-dominated, synchronal coordinating, urbanization lagging, stepwise break-in, exorbitant urbanization, fragile ecology, rudimentary break-in and unsustainable types. Finally, based on an interactive coercion model, the degree of interactive coercion can be examined, and then, an evolutionary cycle can be divided into four phases, namely rudimentary symbiosis, harm

关键词： urbanization process eco-environment interactive coercing relationship interactive coercing rules interactive coercingdegree

Growth Units and Formation Mechanisms of the Crystals Under Hydrothermal Conditions

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Science China Chemistry 1994年第11期37卷 1288-1297页

作者：仲维卓刘光照施尔畏华素坤唐鼎元赵庆兰 Shanghai institute of Ceramics Academia SinicaShanghai 200050PRC Fujian institute of research of the Structure of Matter Academia SinicaFuzhou 350002PRC Fujian institute of research on the Structure of Matter Academia SinicaFuzhou 350002PRC

The growth units and formation mechanisms of quartz(SiO_2)and barium titanate (BaTiO_3)crystals under hydrothermal conditions have been investigated by means of cataphoretic experi- *** is proposed that the growth units of the crystals in hydrothermal solutions have the structures of coordinative polyhedra of anions,which correspond to those of coordinative polyhedra in the crystals. The relationship between crystal morphology and physico-chemical conditions has been explained accord- ing to the modes of incorporation of the coordinative polyhedra of anions on the various faces of crystals. The dimensions of the growth units vary with the change of the growth *** incorporation rates on the various faces of the growth units with varied dimensions must be different,which leads to a satis- factory explanation for the variety of the crystal morphology.

关键词： growth unit coordinative polyhedra of anion crystallization habit

Tribological behaviors of turbofan seal couples from friction heat perspective under high-speed rubbing condition

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Friction 2016年第2期4卷 176-190页

作者： Siyang GAO Weihai XUE Deli DUAN Shu LI institute of Metal research Chinese Academy of Sciences Shenyang 110016 China

The tribological behaviors of two types of seal coatings, nickel-graphite and aluminum-hexagon-boron nitride (Ni-Cg and Al-hBN, respectively) versus a Ti-6Al-4V blade used in turbofan engines were investigated using a high-speed rubbing test. The wear status and damage mechanism of the friction couples were studied and the abradability of the seal coatings was evaluated. By analysis of the coating properties and damage mechanism of the seal couple, the friction heat effect was identified as the key factor influencing blade wear forms as well as coating abradability. A one-dimensional heat conduction model was established to estimate the effect of increasing temperature on the friction interface. The results indicated that in the Ni-Cg and Ti-6Al-4V seal couple, the temperature rising rate (TRR) of the Ti-6Al-4V blade was faster than that of the Ni-Cg coating, and so the Ti-6Al-4V blade softened earlier than the Ni-Cg coating, causing the blade to suffer severe wear. In the Al-hBN and Ti-6Al-4V seal couple, the TRR of the Ti-6Al-4V blade was slower than that of the Al-hBN coating, and so the Al-hBN coating softened first; thus, blade damage was reduced or even replaced by coating adhesion. The square root ratio of thermal diffusivity between the blade and the coating could be taken as an indicator of the ratio of TRR between the blade and coating to predict blade wear status as well as damage mechanism. The results of the model agreed well with the experiment results of the two seal couples used in this study.

关键词： seal coating high-speed rubbing wear mechanism friction heat thermophysical property

Shape reconstruction of large optical surface with high-order terms in fringe reflection technique

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Frontiers of Optoelectronics 2019年第2期12卷 180-189页

作者： Xiaoli JING Haobo CHENG Yongfu WEN School of Optics and Photonics Beijing Institute of Technology Beijing 100081China Shenzhen research institute Beijing Institute of TechnologyShenzhen 518057China

A fast and effective shape reconstruction method of large aspheric specular surfaces with high order terms is proposed in fringe reflection technique, which combines modal estimation with high-order finite- difference algorithm. The iterative equation with high- order truncation errors is derived for calculating the specular surface with large aperture based on high-order finite-difference algorithm. To achieve the wavefront estimation and improve convergence speed, the numerical orthogonal transformation method based on Zemike polynomials is implemented to obtain the initial iteration value. The reconstruction results of simulated surface identified the advantages of the proposed method. Furthermore, a freeform in illuminating system has been used to demonstrate the validity of the improved method in practical measurement. The results show that the proposed method has the advantages of making the reconstruction of different shape apertures accurate and rapid. In general, this method performs well in measuring large complex objects with high frequency information in practical measurement.

关键词： shape reconstruction fringe reflection techni-que Zemike orthogonal transformation finite difference measurement

Unmanned aerial vehicle positioning based on multi-sensor information fusion

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Geo-Spatial Information Science 2018年第4期21卷 302-310页

作者： Wenjun Li Zhaoyu Fu The 710th research institute of China Shipbuilding Industry Corporation YichangChina

Unmanned aerial vehicle(UAV)positioning is one of the key techniques in the field of UAV *** the high positioning precision of UAV can be achieved through global positioning system(GPS),the frequency of updating signal in GPS is low and the energy consumption of GPS module is huge,which does not satisfy the real-time demand of UAV *** this paper,a multi-sensor information fusion method based on GPS,inertial navigation system(INS),and the visible light sensors is proposed for UAV *** Kalman filter combining with simulated annealing algorithm is used to estimate the position error between GPS or INS and the visible light sensors,and then the motion trajectory is corrected according to this position error ***,the positioning accuracy of UAV can be improved in case of only INS being *** results demonstrate that the proposed method can remarkably improve the positioning accuracy and greatly reduce the energy consumption.

关键词： Kalman filter algorithm simulated annealing algorithm target tracking integrated positioning system

Effects of V and Zr Additions on Microstructures and Mechanical Properties of Nb-Ti-Al-Base Alloys

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稀有金属材料与工程 2009年第A3期38卷 5-7页

作者： Bai Run Zheng Xin Li Zhongkui Wang Donghui Xia Mingxing Northwest institute for Nonferrous Metal research Xi＇an 710016 China

Microstructures and mechanical properties of Nb-32Ti-7Al alloys containing different V and Zr contents were investigated. The microstructures were characterized using optical microscopy and scanning electron microscopy (SEM). The alloy with V and Zr presents single phase Nb solid solution (Nbss). Tensile testing was carried out at room temperature and 1373 K. The results show that these alloys have good ductility at room temperature. The strengths at room and high temperature increase with the addition of V and Zr, but the room temperature ductility decrease.

关键词：力学性能光学显微镜铌扫描电子显微镜