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Journal of wuhan university of technology(Materials Science) 2009年第6期24卷 903-906页

作者：李建青袁松柳 school of Sciences Huazhong University of Science and Technology

Systematical investigations of zero-field resistivity, magnetoresistance and magnetization were performed for a typical manganese compound La2/3Ca1/3MnO3. It is argued that the common origin for insulator-metal and paramagenetic ferromagnetic-transitions as well as colossal magnetoresistance is due to the formation of ferromagnetic clusters in the paramagnetic background. The transition to metallic state is resulted from percolation of ferromagnetic metallic clusters, while the colossal magnetoresistance is due to the application of magnetic field, which accelerates the growth of ferromagnetic metallic clusters and causes the shift of the onset temperature for the metallic percolation to higher temperature. Based on the random resistor network model, the zero-field resistivity versus temperature dependence is simulated by using experimental parameters, and experimental data well agree with those in whole temperature range, giving a strong support to our approach.

关键词： percolation colossal magnetoresistance insulator-metal transition

Polarity for a Class of Levy Processes

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wuhan university Journal of Natural Sciences 2002年第4期7卷 394-398页

作者： Wu Chuan ju 1,2 , Liu Lu qin 1 1. school of Mathematics and Statistics, wuhan university, wuhan 430072, hubei, china 2. College of Urban Construction, wuhan university of Science and technology, wuhan 430070, hubei, china wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) wuhan university of Science and technology College of Urban Construction Wuhan Hubei China (GRID:grid.412787.f) (ISNI:***) wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

Polar set of Markov processes is an important concept in probabilistic potential theory, but it is not easy to judge the polarity of the sets. In this paper, we give some results which can be easily used to examine the polarity of the sets whenX t belongs to a special class of Levy processes. We also give a result about polar functions of symmetric stable processes.

关键词： Levy process subordinator (essentially) polar set polar function

One Method for Improving RAID5 Performance

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wuhan university Journal of Natural Sciences 2000年第3期5卷 289-292页

作者： Chen Qiong, Zhang Jiang-ling, Feng Dan school of Computer Science and Engineering, huazhong university of Science and T echnology, wuhan 430074, china huazhong university of Science and technology School of Computer Science and Engineering Wuhan China (GRID:grid.33199.31) (ISNI:***)

As a kind of parallel storage system, RAID5 has been becoming a popular solution for providing better performance at low cost and without sacrificing much redundant data, its main disadvantage is poor performance. It is a general method to improve RAID5 performance by using cache. However, it often happens that the data is not hit in cache, in this case, the RAID5 performance also will be very poor. The method based on combination of disk I/O operations has been proposed for impriving the I/O response time through reducing the number of low-level operations. According to theoretic analysis and experimental test, we find that RAID5 access time and data transfer rate could be largely improved than conventional method.

关键词： Key words RAID I/O combination access time response time data transfer rate

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2, JIN Zhenmin1,3, QU Jing2 & WANG Lu2 1. State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, wuhan 430074, china 2. Graduate school of china university of Geosciences, wuhan 430074, china 3. Faculty of Earth Sciences, china university of Geosciences, wuhan 430074, china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Graduate school of china university of Geosciences 430074 Wuhan China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 300 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Code Component Reuse Supporting Environment (CCRSE) and Its Design Strategy

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wuhan university Journal of Natural Sciences 2003年第2A期8卷 363-367页

作者： Ying Shi, Xu Gang,Yuan Sheng-qiong, Chen HaoState Key Laboratory of software Engineering, wuhan university, wuhan 430072, hubei, china wuhan university

Code Component Reuse Supporting Environment (CCRSE), which has been developed by us, is an integrated development environment. CCRSE can provide comprehensive supports for the whole process of reusing code component in the manner of dynamic composition. The architecture and functionality of CCRSE are introduced. The key achievement is giving the three strategies that are vital to successfully design CCRSE. The three strategies include: (1) according to the three pivotal technologies (encapsulation, composition and management) for supporting composition reuse of code component, design three tools respectively. (2) keep tool for supporting code component development independent of tool for supporting code component composition. (3) strictly restrict code component specification, provide the strong plug and play support for code component composition reuse, and furthest provide transparence to strictly restricted specification of code component in development of component itself.

关键词： Codes (symbols) Design Management

Accountability Analysis of Electronic Commerce Protocols by Finite Automaton Model

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wuhan university Journal of Natural Sciences 2004年第3期9卷 293-295页

作者： Xie Xiao-yao 1,2 , Zhang Huan-guo 1 1. school of Computer, wuhan university, wuhan 430072, hubei, china 2. Institute of Network technology, Guizhou university of technology, Guiyang 550003, Guizhou, china wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Guizhou university of technology Institute of Network Technology Guiyang Guizhou China (GRID:grid.443382.a) (ISNI:***) wuhan university School of Computer Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The accountability of electronic commerce protocols is an important aspect to insures security of electronic transaction. This paper proposes to use Finite Automaton (FA) model as a new kind of framework to analyze the transaction protocols in the application of electronic commerce. Key words finite automaton - electronic commerce - nonrepudiation - information security CLC number TP 393. 08 Foundation item: Supported by the National Natural Science Foundation of china (66973034, 90104005, 60373087)Biography: Xie Xiao-yao (1952-), male, Professor, Ph. D candidate, research direction: information security.

关键词： finite automaton electronic commerce nonrepudiation information security

Artificial Intelligence Embedded Object-Oriented Methodology For Model Based Decision Support

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Journal of Systems Engineering and Electronics 1996年第1期7卷 1-14页

作者： Feng Shan Tian Yuan Li Tong & Cai Jun (Institute of System Engineering, Department of Automatic Control Engineering huazhong university of Science and technology, wuhan, hubei, 430074, P. R. china) Institute of System Engineering Department of Automatic Control Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 P. R. China

The paper presents the coupling of artificial intelligence-AI and Object-oriented methodology applied for the construction of the model-based decision support system *** MBDSS is designed for support the strategic decision making lead to the achievemellt of optimal path towardsmarket economy from the central planning situation in china. To meet user's various requirements,a series of innovations in software development have been carried out, such as system formalization with OBFRAMEs in an object-oriented paradigm for problem solving automation and techniques of modules intelligent cooperation, hybrid system of reasoning, connectionist framework utilization,etc. Integration technology has been highly emphasized and discussed in this article and an outlook to future software engineering is given in the conclusion section.

关键词： Artificial intelligence Object-oriented methodology Knowledge-based systems Intelligently cooperative systems Neural nets Case hased reasoning Behavioral science,Advancedautomation.

Model Tests of Pile Defect Detection

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Journal of china university of Geosciences 2001年第4期12卷 321-324页

作者： Li Guocheng Wang Jingtao school of Civil Engineering , huazhong university of Science and technology , wuhan 430074 school of Civil Engineering Huazhong University of Science and Technology Wuhan 430074

The pile, as an important foundation style, is being used in engineering practice. Defects of different types and damages of different degrees easily occur during the process of pile construction. So, dietecting defects of the pile is very important. As so far, there are some difficult problems in pile defect detection. Based on stress wave theory, some of these typical difficult problems were studied through model tests. The analyses of the test results are carried out and some significant results of the low-strain method are obtained, when a pile has a gradually-decreasing crosssection part, the amplitude of the reflective signal originating from the defect is dependent on the decreasing value of the rate of crosssection β. No apparent signal reflected from the necking appeares on the velocity response curve when the value of β is less than about 3. 5 %.

关键词： model tests pile defect detection stress wave responses.

EXPERIMENTAL INVESTIGATIONS OF CAVITATION EFFECTS ON FLOW CHARACTERISTICS OF SMALL ORIFICES AND VALVES IN WATER HYDRAULICS

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Chinese Journal of Mechanical Engineering 2002年第4期15卷 380-384页

作者： Zhu Bihai Zhang Tiehua Huang Yan Li Zhuangyun school of Mechanical Engineering, huazhong university of Science and technology,wuhan 430074, china school of Mechanical Engineering Huazhong University of Science and Technology Wuhan 430074

The flow characteristics and cavitation effects of water passing throughsmall sharp-edged cylindrical orifices and valves of different shapes in water hydraulics areinvestigated. The test results using orifices with different aspect ratios and different diametersshow that the flow coefficients in the case of non-cavitating flow are larger than that of flow inthe case of cavitation occurrence. The flow coefficients of flow with cavitation initially decreaseas Reynolds number increases and ultimately tend to be of constant values close to contractioncoefficient. Large aspect ratio has an effect of suppressing cavitation. The experimental resultsabout disc valves illustrate that the valves with sharp edge at large opening are less affected bycavitation than that at small opening. Throttle with triangle notch has better anti-cavitationability than that with square notch. The flowrate of the throttle with square notch is significantlyaffected by the flow direction or the flow passage shape.

关键词： cavitation flow characteristics small orifices water hydraulic valves

Determination of the Thermal Expansion Coefficient of Concrete at Early Ages by Using Temperature-stress Testing Machine

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Journal of wuhan university of technology(Materials Science) 2006年第4期21卷 146-149页

作者：霍凯成 hubei Key Laboratory of Roadway Bridge & Structure Engineering Wuhan University of TechnologyWuhan 430070China

By using the uptodate temperatuer-stress testing machine, the thermal expansion coefficient of concrete at early ages was studied and indicative conclusions were achieved ： temperature rising due to hydration heat is not directly correlated with cracking, but the temperature and stress evolation process should be taken into consideration in the same time. Proper chemical admixtures and mineral cornpasitions can improve the mechanical properties of concrete such as thermal expansion coefficient, which is very indicative in practice.

关键词： concrete coefficient of thermal expansion temperature-stress test