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Mechanism for calcite dissolution and its contribution to development of reservoir porosity and permeability in the Kela 2.gas field,Tarim Basin,china

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Science china Earth Sciences 2008年第4期51卷 567-578页

作者： YU BingSong1,3, DONG HailLiang2.3 & RUAN Zhuang1,3 1 State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Beijing 100083, china 2.Department of Geology, Miami university,Oxford, OH 45056, USA 3 Geomicrobiology Laboratory, china university of Geosciences, Beijing, 100083, china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Department of Geology Miami University Geomicrobiology Laboratory China University of Geosciences

This study is undertaken to understand how calcite precipitation and dissolution contributes to depth-related changes in porosity and permeability of gas-bearing sandstone reservoirs in the Kela 2.gas field of the Tarim Basin, Northwestern china. Sandstone samples and pore water samples are col-lected from well KL2.1 in the Tarim Basin. Vertical profiles of porosity, permeability, pore water chem-istry, and the relative volume abundance of calcite/dolomite are constructed from 3600 to 4000 m below the ground surface within major oil and gas reservoir rocks. Porosity and permeability values are in-versely correlated with the calcite abundance, indicating that calcite dissolution and precipitation may be controlling porosity and permeability of the reservoir rocks. Pore water chemistry exhibits a sys-tematic variation from the Na2.O4 type at the shallow depth (3600-3630 m), to the NaHCO3 type at the intermediate depth (3630―3695 m),and to the CaCl2.type at the greater depth (372.―3938 m). The geochemical factors that control the calcite solubility include pH, temperature, pressure, Ca2. concen-tration, the total inorganic carbon concentration (ΣCO2., and the type of pore water. Thermodynamic phase equilibrium and mass conservation laws are applied to calculate the calcite saturation state as a function of a few key parameters. The model calculation illustrates that the calcite solubility is strongly dependent on the chemical composition of pore water, mainly the concentration difference between the total dissolved inorganic carbon and dissolved calcium concentration (i.e., [ΣCO2. -[Ca2.]). In the Na2.O4 water at the shallow depth, this index is close to 0, pore water is near the calcite solubility. Calcite does not dissolve or precipitate in significant quantities. In the NaHCO3 water at the intermedi-ate depth, this index is greater than 0, and pore water is supersaturated with respect to calcite. Massive calcite precipitation was observed at this depth interval and

关键词： calcite dissolution porosity thermodynamic Tarim Basin

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Heuristic for no-wait flow shops with makespan minimization based on total idle-time increments

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Science in china(Series F) 2008年第7期51卷 896-909页

作者： LI XiaoPing1,2.& WU Cheng3 1 School of Computer Science & Engineering, southeast university, Nanjing 2.0096, {2. 2.Key Laboratory of Computer Network and Information Integration (southeast university), Ministry of Education, Nanjing 2.0096, {2. 3 Department of automation, Tsinghua university, Beijing 100084, {2. School of Computer Science & Engineering Southeast University Key Laboratory of Computer Network and Information Integration (southeast university) Ministry of Education Department of automation Tsinghua University

No-wait flow shops with makespan minimization are classified as NP-hard. In this paper, the optimization objective is equivalently transformed to total idle-time minimization. The independence relationship between tasks is analyzed, and objective increment properties are established for the fundamental operators of the heuristics. The quality of the new schedules generated during a heuristic is judged only by objective increments and not by the traditional method, which computes and compares the objective of a whole schedule. Based on objective increments, the time complexity of the heuristic can be decreased by one order. A seed phase is presented to generate an initial solution according to the transformed objective. Construction and improvement phases are introduced by experimental analysis. The FCH （fast composite heuristic） is proposed and compared with the most effective algorithms currently available for the considered problem. Experimental results show that the effectiveness of the FCH is similar to that of the best methods but requires far less computation time. The FCH can also be efficient in real time scheduling and rescheduling for no-wait flow shops.

关键词： no-wait flow shops heuristic makespan Tabu search

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An Intelligent Otologic Drill

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Journal of Otology 2010年第2期5卷 104-110页

作者： SHEN Peng1,FENG Guo-dong2.CAO Tian-yang 3,GAO Zhi-qiang 2.LI Xi-sheng 3 1 Department of Otolaryngology,Chuiyangliu Hospital of Beijing 2.Department of Otolaryngology,Peking Union Medical college Hospital,Chinese Academy of Medical Sciences and Peking Union Medical college,Beijing,{2. 3 School of Information & Engineering,university of Science and technology Beijing,Beijing,{2. Department of Otolaryngology Chuiyangliu Hospital of Beijing Department of Otolaryngology Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China School of Information & Engineering University of Science and Technology Beijing Beijing China

Objective To test a modified otologic drill under different drilling conditions for its ability to identify drilling faults and stop *** Based on force analysis and previous works,an otologic drill was modified and equipped with three *** various conditions,the drill was used to simulate three drilling faults and normal drilling,and signals from the drill were analyzed to extract the characteristic signal.A multi-sensor information fusion system and a stop program were designed to recognize drilling faults and stop *** Signals from each sensor changed consistently in response to drilling condition changes,with high repeatability and *** average identification rate was 72.62.%,68.575%,70.5% and 81.3% respectively for the three simulated drilling faults and normal *** stop program stopped drilling in 0.2. 0.3 seconds when a drilling faults was *** This study shows that the forces acting on the drill bit change predictably in the three simulated drilling conditions;that using suitable BP neural networks,the drilling faults can be reliably identified,and that a stop program based upon characteristic signal recognition can stop drilling quickly upon detecting drilling *** lays a foundation for development of a system capable of predicting drilling faults and automatic drill *** studies are being undertaken for practical application of such a system.

关键词： drill otologic surgery force sensor back propagation(BP) neural network

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An analysis of the types and distribution characteristics of natural gas reservoirs in china

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Petroleum Science 2009年第1期6卷 38-42页

作者： Xu Zhangyou Yue Dali Wu Shenghe Zhang Xiaoyu Chen Ce Ni Yuqiang 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

The natural gas reservoir beds of different areas in china can be divided into three kinds, clastic natural gas reservoir bed, carbonate natural gas reservoir bed and special natural gas reservoir bed. They have different combination patterns controlled by deposition, diagenesis and tectonism. Our analysis indicates that the natural gas reservoirs are mainly distributed in the Precambrian, Palaeozoic, Mesozoic, and Tertiary-Quaternary. Craton basin, foreland basin and intracontinental rift basin which contain most of natural gas in china have special geological features and favorable accumulation conditions, and will be important exploration areas in the future.

关键词： Natural gas clastic reservoir carbonate reservoir gas-bearing basin china

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Balanced multiple description subband coding based on multifilter banks

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Science china(Information Sciences) 2011年第11期54卷 2359-2372页

作者： WANG Ning 1,LI BaoBin 2.& PENG LiZhong 1 1 LMAM,School of Mathematical Sciences,Peking university,Beijing 100871,china 2.School of Information Science and Engineering,Graduate university of Chinese Academy of Sciences,Beijing 100190,china LMAM School of Mathematical Sciences Peking University School of Information Science and Engineering Graduate University of Chinese Academy of Sciences

Multiple description coding is one of the source coding techniques to alleviate the problems of packet loss in *** encoder generates several different descriptions of the source and the decoder can produce a useful reconstruction with any received subset of these *** of the earlier works concentrated on redundancy and the average distortion of the single-description reconstructions,which is insufficient to describe the *** this paper,a metric of the coding system,balance eccentric modulus,is defined to evaluate the difference in quality between the individual *** the discrete wavelet transform becomes trivial polyphase transform when setting the balance eccentric modulus at zero,we introduce a multiwavelet based scheme ***,a sufficient condition for balanced multiwavelet based multiple description coding is presented.

关键词： multiple description coding rate-distortion theory balance eccentric modulus balanced multiwavelet multifilter bank

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Development of Novel Binder for Hardmetal Powder Extrusion Molding

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Journal of Materials Science & technology 2002年第6期18卷 569-571页

作者： Jicheng ZHOU and Baiyun HUANGState Key Laboratory for Powder Metallurgy, Central south university , Changsha 410083, {2. Lab. for Power Metall. Central South Univ. Changsha 410083 China

A novel binder system for hardmetal powder extrusion moulding (PEM) process has been developed. The binder system comprises a major fraction of a mixture of low molecular weight components (LMWCs) and a minor fraction of very finely dispersed polymer. The feedstocks are mixed as a thick slurry at a suitable temperature and are rapidly homogenized by stirring at an adequate shear force. The binders are removed by thermal debinding. The thermal debinding mechanism has been investigated by thermogravimetry (TG) and differential thermogravimetry (DTG). At the first stage of debinding, the LMWCs are removed. These open up pore channels which allows much faster removal of the remaining polymer component during the subsequent stage. The microstructures of the moulded green parts were observed by scanning electron microscopy (SEM). The debound samples were sintered at different temperatures, and the sintered samples properties were measured.

关键词： Binder Thermal debinding Hardmetal powder extrusion moulding

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Mechanisms of the pancake vortex and vortex line movement in the high T_c superconductors Bi_2.r_2.aCu_2._8+δ and La_(1.93)Sr0.0_7CuO_4+δ

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Science china(Physics,Mechanics & Astronomy) 2007年第2期50卷 240-248页

作者： WANG WeiXian1,ZHOU Fang2.TAN Shun1,WU Huan1 & ZHANG YuHeng1 1 National High Magnetic Field Laboratory,university of Science and technology of {2.,Hefei 2.002.,{2. 2.National Laboratory for Superconductivity,lnstitute of Physics and the Center for Condensed Matter Physics,Chinese Academy of Sciences,Beijing 100080,{2. National High Magnetic Field Laboratory University of Science and Technology of China Hefei China National Laboratory for Superconductivity Institute of Physics and the Center for Condensed Matter Physics Chinese Academy of Sciences Beijing China

In the strict sense, it is not very clear why with magnetic field increasing, the normal-superconductive (NS) transition becomes broad for Bi2.r2.aCu2.8+δ(Bi2.12. while the NS transitions are almost parallel for La193Sroo7Cu04+δ(La2.4). In this paper, R-T relations are measured by the six-probe method. We propose a moving mechanism of the pancake vortex and vortex line for Bi2.12. The theoretical curves fit the experiment data well.

关键词： superconductivity superconductive pancake vortex dynamics

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FRACTAL BLOCK CODING IN RESIDUE DOMAIN

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Journal of Electronics(china) 1997年第3期14卷 236-240页

作者： Wang Zhou Deng Huaqiu Yu Yinglin(Dept. of Elect. & Comm. Eng., south china university of technology, guangzhou 510641)

A new block-based fractal image coding algorithm called Fractal Block Coding in Residue Domain (FBCRD) is proposed. In basic Fractal Block Coding (FBC) algorithm, each block (called range block) is encoded by an affine mapping from a domain block within the same image to itself. The decoder uses the parameters of these mappings to synthesize the reconstructed image through an iterative procedure. FBCRD is a modification of basic FBC. In FBCRD, range blocks and domain blocks are all residue blocks subtracted from their block means and both the parameters of affine mappings and block means are coded. This modification leads to fewer iterations at the decoder. An optimized decoding strategy is also introduced which reduces total decoding time by more than half of that of basic FBC. This improvement is favorable for real time implementation of fractal image compression.

关键词： Image coding Fractal Decoder iteration Fractal block coding

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Treatment outcomes for different subgroups of nasopharyngeal carcinoma patients treated with intensity-modulated radiation therapy

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Chinese Journal of Cancer 2011年第8期30卷 565-573页

作者： Sheng-Fa Su 1,2.3,Fei Han 1,2.Chong Zhao 1,2.Ying Huang 1,2.Chun-Yan Chen 1,2.Wei-Wei Xiao 1,2.Jia-Xin Li 1,2.and Tai-Xiang Lu 1,2.1 State Key Laboratory of Oncology in south china,{2.,Guangdong 510060,P.R.china 2.Department of Radiation Oncology,Sun Yat-sen university Cancer Center,{2.,Guangdong 510060,P.R.china 3 Department of Oncology,Guiyang Medical college Hospital,Tumor Hospital of Guizhou,Guiyang,Guizhou 550003,P.R.china. StateKeyLaboratoryofOncologyinsouthchina Guangzhou510060 DepartmentofRadiationOncology SunYat-senUniversityCancerCenterGuangzhou510060 DepartmentofOncology GuiyangMedicalCollegeHospitalTumorHospitalofGuizhou

Although many studies have investigated intensity-modulated radiation therapy (IMRT) for nasopharyngeal carcinoma (NPC),sample sizes in the reported studies are usually small and different in outcomes in different T and N subgroups are seldom ***,we evaluated the outcomes of NPC patients treated with IMRT and further explored treatment strategy to improve such *** collected clinical data of 865 NPC patients treated with IMRT alone or in combination with chemotherapy,and classified all cases into the following prognostic categories according to different TNM stages:early stage group (T1-2.0-1M0),advanced local disease group (T3-4N0-1M0),advanced nodal disease group (T1-2.2.3M0),and advanced locoregional disease group (T3-4N2.3M0).The 5-year overall survival (OS),local relapse-free survival (LRFS),and distant metastases-free survival (DMFS) were 83.0%,90.4%,and 84.0%,*** early disease group had the lowest treatment failure rate,with a 5-year OS of 95.6%.The advanced local disease group and advanced nodal disease group had similar failure pattern and treatment outcomes as well as similar hazard ratios for death (4.2.0 and 4.62.,respectively).The advanced locoregional disease group had the highest incidence of relapse and death,with a 5-year DMFS and OS of 62.3% and 62.2.,respectively,and a hazard ratio for death of *** with IMRT alone,IMRT in combination with chemotherapy provided no significant benefit to locoregionally advanced *** results suggest that the decision of treatment strategy for NPC patients should consider combinations of T and N stages,and that IMRT alone for early stage NPC patients can produce satisfactory ***,for advanced local,nodal,and locoregional disease groups,a combination of chemotherapy and radiotherapy is recommended.

关键词：放射治疗强度调制鼻咽癌患者调控样本大小临床资料结合治疗

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搜索引擎分类研究的现状与发展

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图书馆论坛 2005年第1期25卷 69-71页

作者：苏坤夏旭南京工业职业技术学院江苏南京210013 南方医科大学图书馆广东广州510515

基于搜索引擎分类研究现状和进展, 提出了搜索引擎分类的基本原则和标准。

关键词：搜索引擎分类体系类目体系分类标准

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