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New Refinement Relations of Z Specifications for Multiple Viewpoints Oriented Requirements Method

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wuhan university Journal of Natural Sciences 2001年第Z1期6卷 304-312页

作者： He Yan xiang, Song Qiang, Huang Qian school of Computer, State Key Laboratory of software Engineering wuhan university, wuhan 430072, china school of Computer State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 China

In this paper we develop several new refinement relations of Z for multiple viewpoints oriented requirements method (MVORM). The original motivation is that we found the standard Z refinement relation is not adequate or correct when considering specifications that have temporal relationships of operations. The concept of temporal state variables is introduced into Z. Then new implementation relations are defined and new refinement relations are deduced, mainly for temporal state variables to process temporal relationships of operations. We use state transition systems to abstract the temporal state transitions. A simple example is used to show the procedures of MVORM. Finally some directions of further work are forwarded.

关键词： temporal state variable formal description language state transition system implementation relation refinement relation multiple viewpoints oriented requirements method

UNIFORM ESTIMATE ON FINITE TIME RUIN PROBABILITIES WITH RANDOM INTEREST RATE

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Acta Mathematica Scientia 2010年第3期30卷 688-700页

作者：明瑞星何晓霞胡亦钧刘娟 school of Mathematics and Information Sciences Jiangxi Normal University school of Mathematics and Statistics Wuhan University College of Science Wuhan University of Science and Technology College of Mathematics and Statistics Hubei Normal University

We consider a discrete time risk model in which the net payout （insurance risk） {Xk, k = 1, 2,...} are assumed to take real values and belong to the heavy-tailed class L∩ D and the discount factors （financial risk） {Yk, k = 1,2,...} concentrate on [θ, L], where 0 〈 0 〈 1, L 〈 ∞, {Xk, k = 1,2,...}, and {Yk, k=1,2,...} are assumed to be mutually independent. We investigate the asymptotic behavior of the ruin probability within a finite time horizon as the initial capital tends to infinity, and figure out that the convergence holds uniformly for all n ≥ 1, which is different from Tang Q H and Tsitsiashvili G （Adv Appl Prob, 2004, 36： 12.8-12.9）.

关键词： Random interest rate finite time ruin probability uniformity

Effect of Substrate-Water Interaction on the Wetting Behavior in Water-Oil and Substrate-Water-Oil Systems

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wuhan university Journal of Natural Sciences 2003年第4A期8卷 1097-1102页

作者： Yuan Yin-quan 1,2 , Zou Xian-wu 1 , Jin Zhun-zhi 1 1. school of Physics and technology, wuhan university, wuhan 430072, hubei, china 2. Department of Physics, Xiaogan university, Xiaogan 432100, hubei, china wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Xiaogan university Department of Physics Xiaogan Hubei China (GRID:grid.49470.3e) wuhan university School of Physics and Technology Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

The effects of the substrate-water interaction on the wetting behavior in water-oil and surfactant-water-oil systems confined by one substrate which has the preferential interaction to one species of particles have been investigated by using the free energy analysis and discontinuous molecular dynamic simulations. As the preferential interaction between the substrate and water particles varies from small repulsion to large attraction, the partial drying, partial wetting and complete wetting state are observed in sequence. In addition, the wetting behavior of surfactant aqueous solution on the substrate is not only dependent on the interaction, but also limited by the maximum equilibrium concentration of surfactants at the interface.

关键词： wetting behavior wetting transition preferential interaction substrate

Existence of Equilibrium Solutions to a Size-Structured Predator-Prey System with Functional Response

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wuhan university Journal of Natural Sciences 2009年第5期14卷 383-387页

作者： LIU Keying,LIU Weian school of Mathematics and Statistics,wuhan university,wuhan 430072,hubei,china school of Mathematics and Statistics Wuhan University Wuhan 430072 Hubei China

In this paper, we consider a nonlinear size-structured population model with functional response, which describes the dynamics of a predator-prey system living in a common habitat. We present a kind of functional response for the prey being a plant or algae, and explain its biological meanings. When the vital rates depend both on the individual＇s size and on the total population or only depend on the former, we obtain the existence of equilibrium solutions.

关键词： equilibrium solutions functional response predator- prey system size-structured population model

Combination Reduction:A SYN-Sequence Selection Strategy for Reachability Testing of Concurrent Programs

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wuhan university Journal of Natural Sciences 2007年第6期12卷 1024-1028页

作者： LU Chao LU Yansheng College of Computer Science and technology Huazhong University of Science and Technology Wuhan 430074 Hubei China

Reachability testing is an approach to testing concurrent programs, which can systematically exercise every partially ordered SYN-sequence without constructing the static model. In fact, not all the SYN-sequences need to be tested. This paper proposed a SYN-sequence selection strategy for reachability testing, which can reduce the number of SYN-sequences generated without decreasing the effectiveness of detecting programs＇ errors. We described a simple algorithm to implement the strategy, and then discussed several optimizations to the algorithm. Experiments have been carried out in a case study to verify the efficacy of the strategy.

关键词： software testing reachability testing concurrency SYN-sequence

The Research and Application of Prediction Control in Multi-variable Control Process

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武汉理工大学学报 2006年第S3期28卷 850-857页

作者： WEI Shuangying school of Management,wuhan university of technology,wuhan 430070,china school of Management Wuhan University of TechnologyWuhan 430070China

The modern industrial control objects become more and more complicated,and higher control quality is required, so a series of new control strategies appear,applied,modified and develop *** paper researches a new control strategy- prediction control-and its application in Multi-Variable Control *** research result is worthy for automatic control in pro- cess industry.

关键词： prediction control rolled optimization feedback calibration multi-variable control system identify system control

Research on the Recovery of the Transported Static Image with Channel Errors

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wuhan university Journal of Natural Sciences 2002年第3期7卷 297-301页

作者： Liu Huai\|lin, Chen Shu\|zhen  school of Electronic Information, wuhan university, wuhan 430072, hubei,china school of Electronic Information Wuhan University Wuhan Hubei China

A discussion is presented to gain the relationship between the original image and the reconstructed image while errors are mixed with the DCT data of the original image for the transmission. We can find the wrong reconstructed blocks, locate blocks, which are most likely to contain errors and eliminate errors. The method needs no channel error protection, needs no verifiable bits, and needs no extra bandwidth. Experimental results are provided in the end.

关键词： Key words DCT IDCT reconstructed image continuity

Evolution Mechanism of Slip Zone Under Fluctuation of Ground Water Table of Landslide

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地学前缘 2009年第S1期16卷 55-56页

作者： Bo Chai~1,Kunlong Yin~2 1.school of Environmental Studies,china university of Geosciences(wuhan),wuhan 430074,china. 2.Engineering Faculty,china university of Geosciences(wuhan),wuhan 430074,china

The fluctuation of ground water table of landslide caused by the changing of rain fall and reservoir water level leads the slip zone to possess the complicated deformation features of stepped and *** role of the groun... 详细信息

关键词： groundwater fluctuation slip zone landslide

A Necessary Condition on Comparison Theorem for One-Dimensional Stochastic Differential Equation

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wuhan university Journal of Natural Sciences 2010年第1期15卷 13-15页

作者： ZHAO Shoujiang,GAO Fuqing school of Mathematics and Statistics,wuhan university,wuhan 430072,hubei,china school of Mathematics and Statistics Wuhan University Wuhan China

We consider the comparison theorem of one-dimensional stochastic differential equation with non-Lipschitz diffusion coefficient. Considering the two one-dimensional stochastic differential equations as a two-dimension... 详细信息

关键词： comparison theorem Ito formula necessary condition