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Application of splitting scheme and multigrid method for TV-Stokes denoising

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Science China(Information sciences) 2011年第4期54卷 745-756页

作者： CHANG QianShun 1,TAI XueCheng 2 & XING LiLi 3.1 Institute of Applied Mathematics,Academy of Mathematics and Systems sciences,Chinese Academy of sciences,beijing 100190,China {3. of Mathematics,university of Bergen,Bergen 5007,Norway School of Physical and Mathematical sciences,Nanyang Technological university,63.798,Singapore 3.School of Mathematics and Computational Science,China university of petroleum (East China),Dongying 257061,China 1. Institute of Applied Mathematics Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100190 China2. Department of Mathematics University of Bergen Bergen 5007 Norway3. School of Mathematics and Computational Science China University of Petroleum (East China) Dongying 257061 China

Based on some previous work on the connection between image restoration and fluid dynamics,we apply a two-step algorithm for image *** the first step,using a splitting scheme to study a nonlinear Stokes equation,tangent vectors are *** the second step,an image is restored to fit the constructed tangent *** apply a fixed point iteration to solve the total variation-based image denoising problem,and use algebraic multigrid method to solve the corresponding linear *** results demonstrate that our algorithm is efficient and robust,and boundary conditions are satisfactory for image denoising.

关键词： image denoising total variation Stokes equation algebraic multigrid method

Fabrication of atomically smooth SrRuO_3.thin films by laser molecular beam epitaxy

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Science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 745-749页

作者： LIU GuoZhen1, HE Meng1, JIN KuiJuan1, YANG GuoZhen1, Lü HuiBin1, ZHAO Kun2, ZHENG ShiJian3.& MA XiuLiang3.1 beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of sciences, beijing 100080, China {3. of Mathematics and Physics, China university of petroleum, beijing 102249, China 3.Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of sciences, Shenyang 110016, China 1. beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China 2. department of Mathematics and Physics China University of Petroleum Beijing 102249 China 3. Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

High-quality SrRuO3.(SRO) thin films and SrTiO3.SRO bilayer were grown epitaxially on SrTiO3.(STO)(001) substrates by laser molecular beam epitaxy. The results of in situ observation of reflection high-energy electron diffraction and ex situ X-ray diffraction θ -2θ scan indicate that the SRO thin films have good crystallinity. The measurements of atomic force microscopy and scan tunneling microscopy reveal that the surface of the SRO thin film is atomically smooth. The resistivity of the SRO thin film is 3.0 μΩ·cm at room temperature. Furthermore, the transmission electron microscopy study shows that the interfaces of STO/SRO and SRO/STO are very clear and no interfacial reaction layer was observed. The experimental results show that the SRO thin film is an excellent electrode material for devices based on perovskite oxide materials.

关键词： SrRuO3 thin film laser molecular beam epitaxy surface morphology

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2 1 department of Physics, China university of petroleum, Dongying 257061, China {3. of Physics, beijing Normal university, beijing 100875, China department of Physics China University of Petroleum Dongying 257061 China department of Physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Geophysical methods for the study of sedimentary cycles

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petroleum Science 2009年第3期6卷 259-265页

作者： Xu Jingling Liu Luofu Wang Guiwen Shen Jinsong Zhang Chunhua School of Resources and Information Technology China University of Petroleum Beijing 102249 China State Key Laboratory of petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China department of Computer Science and Technology China University of Petroleum Beijing 102249 China

We present the wavelet depth-frequency analysis and variable-scale frequency cycle analysis methods to study sedimentary cycles. The spectrum analysis, variable-scale frequency cycle analysis, and wavelet depth-frequency analysis methods are mainly discussed to distinguish sedimentary cycles of different levels. The spectrum analysis method established the relationship between the spectrum characteristics and the thickness and number of sedimentary cycles. Both the variable-scale frequency cycle analysis and the wavelet depth-frequency analysis are based on the wavelet transform. The variable-scale frequency cycle analysis is used to obtain the relationship between the periodic changes of frequency in different scales and sedimentary cycles, and the wavelet depth-frequency analysis is used to obtain the relationship between migration changes of frequency energy clusters and sedimentary cycles. We designed a soft-ware system to process actual logging data from the Changqing Oilfield to analyze the sedimentary cycles, which verified the effectiveness of the three methods, and good results were obtained.

关键词： Sedimentary cycles spectrum analysis wavelet depth-frequency analysis variable-scale frequency cycle analysis

The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2, CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural Resources Re-search, Chinese Academy of sciences, beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry sciences, beijing 100091, China 3. department of Civil Engineering, university of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of sciences, beijing 100085, China 5. College of Resources and Environment, Southwest Agricultural university, Chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of Resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 53. mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2, it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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 102.00,China 3.China petroleum Logging CO. LTD.,Xi’an 710021,China 4 China National Logging Corporation,beijing 100101,China China Univ Petr Beijing 102249 Peoples R China beijing Inst Graph Commun Beijing 102600 Peoples R China China Petr Logging CO LTD Xian 710021 Peoples R China China Natl Logging Corp Beijing 100101 Peoples R 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

Wave coupling between the Tianshan orogen and the deformations in its south and north foreland basins in Cenozoic

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Science China earth sciences 2008年第S2期51卷 61-69页

作者： CHEN ShuPing1,2,TANG LiangJie & YU YiXin1,2 1 State Key Laboratory of petroleum Resource and Prospecting,China university of petroleum,{3. 102249,China 2.department of Geoscience,China university of petroleum,{3. 102249,China China Univ Petr State Key Lab Petr Resource & Prospecting Beijing 102249 Peoples R China China Univ Petr Dept Geosci Beijing 102249 Peoples R China

Attention has been paid to the deformations in the south and north foreland basins of the Tianshan Mountains and their relations to the tectonic movements of the mountains. Based on the seismic data interpretation and field work,the tectonic features,tectonic styles,controlling factors of deformation,deformation time,and their relationships in the three tectonic units were comparably studied. The Ce-nozoic deformations in the two foreland basins were characterized by zonation from south to north,segmentation from west to east,and layering from deep to shallow. The tectonic styles are compres-sive ones,including both basement-involved and cover-detaching. The two foreland basins underwent several times of deformation in Cenozoic and the deformations were transmitted from the Tianshan orogen to the inner basin. The deformation dynamics of the south and north foreland basins of the Tianshan Mountains can be represented by dynamics of orogenic wedges. In terms of the deformations of the wedges with wave-like features,the concept of a wave orogenic wedge was put forward,and a double wave orogenic wedge model was established.

关键词： Tianshan orogen basin-mountain coupling tectonics wave orogenic wedge

Tectonic evolution of the Dabieshan orogen: In the view from polyphase deformation of the Beihuaiyang metamorphic zone

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Science China earth sciences 2005年第7期48卷 886-899页

作者： LIN Wei1, 2, Faure Michel3. WANG Qingchen1 & Arnaud Nicolas4 1. LTE, Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 100029, China 2. department of {3. and Planetary sciences, Graduate School of Science, Nagoya university, Japan 3. ISTO, UMR CNRS 6113. Batiment Géosciences, Orléans Université d’Orléans, 45067 Orléans Cedex 2, France 4. UMR 6524 "Magmas et Volcans", 5 Rue Kessler, 63.00 Clermont-Ferrand, France LTE Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China department of earth and Planetary sciences Graduate School of Science Nagoya University Japan ISTO UMR CNRS 6113 Orléans Université d'Orléans 45067 Orléans Cedex 2 France UMR 6524 Magmas et Volcans 63000 Clermont-Ferrand 5 Rue Kessler France

The Beihuaiyang metamorphic zone was formed by the Early Mesozoic collision of the North and South China Blocks. It consisted of the Foziling and Luzhenguan complexes and was thought to have never afforded a deep subduction. A similar feature of the deformation in the Dabieshan UHP metamorphic rocks implies that these different tectonic units share the same geodynamic background. The early stage of deformation can be preserved on account of their relatively shallower subduction than that for UHP rocks. On the basis of an analysis of the geo- logical structure and geochronological results, five deformational stages have been recognized: a D1-Early compressional deformation which represents the continental subduction; a D2-Early exhumation deformation producing a syn-convergence exhumation; a D3.Main deformation, represented by an exhumation deformation with Late Triassic age; a D4-Doming and its margin extensional gravity collapse deformation and finally a D5-regional extensional deformation of Cretaceous that was mostly introduced by the migmatization and plutonism.

关键词： Beihuaiyang metamorphic zone geometry kinematic polyphase deformation tectonic evolution.

Total alkyl dibenzothiophenes content tracing the filling pathway of condensate reservoir in the Fushan Depression,South China Sea

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Science China earth sciences 2008年第S2期51卷 138-145页

作者： LI MeiJun1,WANG TieGuan1,LIU Ju2,ZHANG MeiZhu2,LU Hong3.MA QinLin2 & GAO LiHui2 1 State Key Laboratory of petroleum Resources and Prospecting,earth sciences and Geoinformatics School,China {3. of petroleum,beijing 102249,China 2 Southern Oil Exploration and Development Company,PetroChina,Guangzhou 510640,China 3.Guangzhou Institute of Geochemistry,Chinese Academy of sciences,Guangzhou 510240,China China Univ Petr Earth Sci & Geoinformat Sch State Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China PetroChina So Oil Explorat & Dev Co Guangzhou 510640 Peoples R China Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510240 Guangdong Peoples R China

The condensates are generally characterized by high maturity,low concentration of steranes and ter-panes biomarkers and low content of non-hydrocarbon fraction. In this case commonly used steranes,terpanes and carbazoles parameters cannot be effectively applied in the reservoir-filling tracing. The hydrogen bond formed by sulfur atom in the dibenzothiophenes (DBTs) results in molecule adsorption and fractionation during oil migration in reservoir. Like carbazoles,total DBTs content decreases with the increasing of oil migration distance. Therefore,a new parameter——total DBTs content is proposed to be used to trace the oil migration orientation and filling pathway. In present study,total DBTs con-tents of condensates and light oils are obtained by adding internal standard——eight deuterium atoms substituted DBT during Gas Chromatography-Mass Spectrometry analysis of aromatic fraction. Except for a few samples with much lower content of non-hydrocarbon fraction,the total DBTs content shows a fine positive correlation with that of carbazoles. Large errors can be caused in the process of pyrrolic nitrogen compounds separation. The application of this new parameter in the Fushan Depression of Beibu Gulf Basin,South China Sea indicates that this parameter is a reliable one to trace filling pathway in condensate reservoirs. Combined with other DBTs-related parameters,such as 4-/1-methydibenzo-thiophene and 2,4-/1,4-dimethyldibenzothiophene,oil migration orientation and filling pathway of the Fushan Depression was determined. The accumulations of Huachang oil field in the Fushan Depres-sion are mainly migrated and charged from northeast to southeast along the Huachang uplift. It can be predicated that the light oil and condensates in the Huachang oil field should be sourced from the source kitchen at the Bailian Sag. It shows that total DBTs content is an effective parameter to tracing oil migration orientation and filling pathway.

关键词： dibenzothiophene alkyl dibenzothiophene condensate reservoir filling pathway molecular markers the Fushan Depression