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Journal of Earth Science 1990年第1期9卷 102-114页

作者： Yin HongfuDepartment of Geology , china university of geosciences , wuhan 43.074

On the basis of a worldwide review of Claraia , Pseudoclaraia and Eumorphotis , especially their important species , two range zones are recognized:the Pseudoclaraia wangi range zone —— Upper Griesbachian——and the Claraia stachei- C. aurita - Eumorphotis multiformis acme zone——Upper Griesbachian to Lower Smithian This result revises both the tradition-al Chinese concept regarding these fossils as limited in Lower Scythian and the viewpoint of some Eurasian researchers who hold Eumorphotis multiformis to be Upper Scythian .The paleogeographical distribution of the three genera is controlled primarily by temperature (latitude) and secondarily by physiographic separations .Distribution of these fossils is subdivided into four realms and five provinces . The Eastern Asia province of the Tethys realm is suggested as the source area of these fossils .The striking contrast between the composition of the species along the southern and northern margins of the Tethys , together with other distributional characters ,supports the plate tectonic theory .

关键词： Lower Triassic ,bivalves paleobiogeography ,stratigraphy .

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 Beijing 100083 China Department of Geology Miami University Oxford OH 45056 USA Geomicrobiology Laboratory China University of Geoscien

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 KL201 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 Na2SO4 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 (3728―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 Na2SO4 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

Global analysis on slope stability and its engineering application

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Science china(Technological Sciences) 2009年第2期52卷 507-512页

作者： ZHENG Hong1,2 & ZHOU ChuangBing3 1 State Key Laboratory of Geomechanics and Geotechnical Engineering, wuhan 430071, china 2 china Three Gorges university, Key Laboratory of Geological Hazards on Three Gorges Reservoir Area, Ministry of Education, Yi Chang 443002, china 3 School of Civil Engineering, wuhan university, wuhan 430072, china 1. State Key Laboratory of Geomechanics and Geotechnical Engineering Wuhan 430071 China 2. china Three Gorges university Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of Education Yi Chang 443002 China 3. School of Civil Engineering Wuhan University Wuhan 430072 China

In hydraulic engineering, sometimes it is necessary to consider the stability of sliding bodies with lateral frictional boundaries. Neither the existing three dimensional limit equilibrium methods nor the commercial software products are able to treat such situations. The three dimensional factor of safety is accordingly underestimated; while the shearing strength based on the three dimensional back analysis is overestimated. In this study, the lateral boundaries are regarded as the part of the slip surface. Based on the expression of the normal pressure on the slip surface and the patch interpolation, a rigorous solution for the three dimensional limit equilibrium analysis is realized. Meanwhile, the proposed procedure is applied to the stability analysis of the slope with a cable platform on the right bank in Da Gang Shan hydraulic project under construction.

关键词： slope stability the limit equilibrium methods three dimensional problems

Comprehensive evaluation of mechanism of "chimney effect" using principles of magnetism, geochemistry and mineralogy

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Chinese Science Bulletin 1998年第9期43卷 743-748页

作者： LIU Qingsheng 1, CHENG Tongjin 2 and LIU Shugen 3 1. Department of Applied Geophysics, china university of geosciences, wuhan 43.074, china 2. Center of Petroleum Geochemistry, china National Star Petroleum Corporation, Hefei 230022, china 3. The St Department of Applied Geophysics China University of Geosciences Wuhan China Center of Petroleum Geochemistry China National Star Petroleum Corporation Hefei China The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of china Chengdu Institute of Technology Chengdu China

Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.

关键词： chimney effect (CE) hydrocarbon microseepage oil/gas accumulation.

Solving A Kind of High Complexity Multi-Objective Problems by A Fast Algorithm

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wuhan university Journal of Natural Sciences 2003年第S1期8卷 183-188页

作者： Zeng San-you, Ding Li-xin, Kang Li-shanDepartment of Computer Science,china university of geosciences, wuhan 43.074, Hubei, china Department of Computer Science, Zhuzhou Institute of Technology , Zhuzhou 412008, Hunan, china State Key Laboratory of Software Engineering, wuhan university, wuhan 430072, Hubei, china china university of geosciences Department of Computer Science Wuhan Hubei China (GRID:grid.162107.3) (ISNI:***) Zhuzhou Institute of Technology Department of Computer Science Zhuzhou Hunan China (GRID:grid.162107.3) china university of geosciences Department of Computer Science Wuhan Hubei China (GRID:grid.162107.3) (ISNI:***) wuhan university State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

A fast algorithm is proposed to solve a kind of high complexity multi-objective problems in this paper. It takes advantages of both the orthogonal design method to search evenly, and the statistical optimal method to speed up the computation. It is very suitable for solving high complexity problems, and quickly yields solutions which converge to the Pareto-optimal set with high precision and uniform distribution. Some complicated multi-objective problems are solved by the algorithm and the results show that the algorithm is not only fast but also superior to other MOGAS and MOEAs, such as the currently efficient algorithm SPEA, in terms of the precision, quantity and distribution of solutions.

关键词： evolutionary algorithms orthogonal design multi-objective optimization Pareto-optimal set

Behavioral Diversity and Complexity Indicated by Metazoan Traces at a Topological Level since Proterozoic

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Journal of Earth Science 2000年第3期19卷 118-124页

作者： Gong Yiming Faculty of Earth Sciences, china university of geosciences, wuhan 43.074, china

On the basis of topological criteria, metazoan traces can be classified as four ichnoorders (clusters) and twenty two ichnofamilies (kinds), which consist of nine basic and three combined topological configurations. At a topological level, the behavioral diversity and complexity indicated by metazoan traces have remained quite stable since the Early Cambrian. Dramatic changes of these traits took place in the Neoproterozoic, in which 75% (12/16) of the topoichnotaxa and all nine basic topological configurations of metazoan traces occurred, but the most complex and highest level topological configuration occurred in the Early Cambrian of the coelomate animal explosive evolution, showing that in the Neoproterozoic and Early Cambrian gestated not only the Ediacarian fauna and all the basic types of multi cellular animals known today, but also all the basic and the most complex metazoan traces through geological time.

关键词： metazoan trace topological configuration Proterozoic.

Capability of evolutionary cryptosystems against differential cryptanalysis

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Science china(Information Sciences) 2011年第10期54卷 1991-2000页

作者： ZHANG HuanGuo 1,2 ,LI ChunLei 1,2 & TANG Ming 1,2 1 School of Computer,wuhan university,wuhan 430072,china 2 Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education,wuhan university,wuhan 430072,china 1. School of Computer Wuhan University Wuhan 430072 China2. Key Laboratory of Aerospace Information Security and Trusted Computing of Ministry of Education Wuhan University Wuhan 430072 China

The evolutionary cryptosystem is a new *** paper studies its security level resisting against differential *** is shown that the evolutionary cryptosystem possesses higher resistance than its initial fixed cryptosystem against differential *** the basis of the relationship among the data complexity,the bit advantage and the success rate of differential cryptanalysis,it is proven that more data is needed for attacking the evolutionary cryptosystem when the bit advantage and success rate are ***,it is shown that the time complexity for attacking the evolutionary cryptosystem is higher than that of differential attacking its initial fixed cryptosystem with the same amount of plaintext-ciphertext *** research indicates that the evolutionary cryptosystem is more robust than its initial fixed cryptosystem against differential cryptanalysis.

关键词： information security cryptology evolutionary cryptosystem cryptanalysis differential cryptanalysis

INFLUENCE OF AGING ON SERRATED FLOW OF ALUMINUM ALLOY LC9

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Acta Metallurgica Sinica(English Letters) 1992年第2期5卷 101-106页

作者： WU Min XU Yuehuang SHEN Gongtian wuhan university,wuhan,china wuhan Univ Wuhan China

The serratedflow of alloy LC9 with different regimes of heat treatment has been investigated at constant rate of *** critieal strain ε_c at the starting of serrated flow increases with the extension of *** activation energy of the process is 0.63 e V which is consistent with the diffusion activation energy of vacancies in *** ε_c decreases while the strain rate ε increases,i.e.,with negative strain rate *** relation is contrary to that of the an- nealed *** shows that the serrated 17ow of annealed sample is controlled by deformation vaeancies,and that of aged sample is controlled by quenching *** den- sity and shape of the serration are changed by *** mechanism of the above mentioned results is discussed.

关键词： serratedflow Cottrell atmosphere aging pinning and depinning

Commission Strategy of the Auction House

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wuhan university Journal of Natural Sciences 2006年第3期11卷 507-510页

作者： WANG Yan~ 1,2 1. College of Economics, Fudan university, Shanghai 200433, china 2. School of Mathematics and Statistics, wuhan university , wuhan 430072, Hubei, china College of Economics Fudan University 200433 Shanghai China School of Mathematics Statistics Wuhan University 430072 Wuhan Hubei China

In a SIPV model, when the commission proportion is not certain, but related with bargain price, generally, it is a linear function of the bargain price, this paper gives bidders＇ equilibrium bidding strategies in the first-and secondprice auctions. We find that the equilibrium strategies in second-price auction are dominant strategies. For seller or auction house, whether the fixed proportion or the unfixed proportion is good is not only related with constant item and the linear coefficient of the linear function, the size of the fixed commission proportion, but also related with the value of the item auctioned. So, in the practical auctions, the seller and the auction house negotiated with each other to decide the commission rules for their own advantage.

关键词： auction commission proportion Bayesian equilibrium bidding strategy

Large deviation principles for stationary NA sequences

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Chinese Science Bulletin 1998年第7期43卷 536-540页

作者： HU Yijun Department of Mathematics, wuhan university, wuhan 430072, china Department of Mathematics Wuhan University Wuhan China

Under general conditions, the large deviation principles for partial sums of stationary NA sequences are proved.

关键词： NA sequence stationary sequence partial sums large deviation principle.