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1.
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. Foundation item: Supported by the National Natural Science Foundation of China under grant 69773046 and (69973017), and Defense Advanced Research Foundation of China under grant (98J15. 1. 1. JW0516) Biography, Chen Qiong (1963-), female, Ph. D candidate, research interests: computer architecture, parallel processing, disk arrays.  相似文献   

2.
Reachability-based analysis and temporal analysis are used to verify the properties of concurrent systems, and it is important to exploit fast and efficient methods. This paper gives semantics of temporal formulae with edges of the transition system of Petri net, and then presents a fast temporal analyzing method, which takes advantage of both Petri net and temporal logic. The method only expands a path of equivalence trace while the path does not satisfy a property according to trace semantics of Petri net, and can validate directly the property on Petri net. Moreover, we exploit a minimal degree of in-out of a node as heuristics to select a path of an equivalence trace. Finally, we demonstrate the validity of the method that decreases state spaces and improves the verification system with the experimental results. Foundation item: Supported by the National Natural Science, Foundation of China (90104005, 66973034) Biography: Fu Jian-ming (1969-) male, Ph.D, research interest: high-speed information network and system safety.  相似文献   

3.
By the property of the solvable group and the extending theorem of group, the authors acquired the structure of one type of Non-Abelian group. And we proved that when order is 10p n (p#2,5) and the sylowp-subgroup is cyclic, the group has twenty types. Whenp#3, it has 12 types and whenp=3, it has 8 types. Foundation item: Supported by the Natural Science Foundation of Hubei Province (No. 99J165) Biography: Huang Ben-wen (1948-), male, Professor, research direction: theory of groups.  相似文献   

4.
Multi-objective Evolutionary Algorithm (MOEA) is becoming a hot research area and quite a few aspects of MOEAs have been studied and discussed. However there are still few literatures discussing the roles of search and selection operators in MOEAs. This paper studied their roles by solving a case of discrete Multi-objective Optimization Problem (MOP): Multi-objective TSP with a new MOEA. In the new MOEA, We adopt an efficient search operator, which has the properties of both crossover and mutation, to generate the new individuals and chose two selection operators: Family Competition and Population Competition with probabilities to realize selection. The simulation experiments showed that this new MOEA could get good uniform solutions representing the Pareto Front and outperformed SPEA in almost every simulation run on this problem. Furthermore, we analyzed its convergence property using finite Markov chain and proved that it could converge to Pareto Front with probability 1. We also find that the convergence property of MOEAs has much relationship with search and selection operators. Foundation item: Supported by the National Natural Science Foundation of China (60133010,70071042,60073043) Biography: Yan Zhen-yu( 1977-), male, Master student, research interests: computational intelligence, evolutionary computation.  相似文献   

5.
The influence of structural design and the parameters of the working electrode on the response time of a solid polymer electrolyte (SPE) carbon monoxide sensor has been studied. Results show that the response time is mainly determined by the RC time constant of the catalyst layer and also related with the working electrode potential. Foundation item: Supported by the National Natural Science Foundation of China (107880233) Biography: Yang Jing (1972-), female, lecturer, reseorch direction: electrochemical sensors.  相似文献   

6.
7.
The certificateless authenticated key agreement protocol proposed by Mandt et al does not haVE the property of key-compromise impersonation (K-CI) resilience. An improved protocol with a simple modification of their protocol is proposed in this paper. In particular, our improved protocol is proved to be immune to the K-CI attack and at the same time possess other security properties.  相似文献   

8.
On the basis of the characteristic parameters selected from the fault sonic signals of cracking hammer with artificial diamond by means of with time series analysis and time domain statistics, three-layer artificial neural network is trained by an improved BP algorithm. The results state that the fault sonic signals can be identified by trained network system precisely. Foundation item: Supported by the National Natural Science Foundation of China Biography: LI Kai-yang (1963-), male, Associate professor. Current research interest is in image processing.  相似文献   

9.
According to the frequency property of Phasedarray ground penetrating radar (PGPR), this paper gives a frequency point slice method based on Wigner time-frequency analysis. This method solves the problem of analysis for the PGPR‘s superposition data and makes detecting outcome simpler and detecting target more recognizable. At last, the analytical, results of road test data of the Three Gorges prove the analytical method efficient.  相似文献   

10.
Based on the definition of tamper evidence, the authors define a new notion of tamper evidence forward secure signature scheme (TE-FSig), and propose a general method to build a TE-FSig scheme. Based on this method, they also give out a concrete instance. A TE-FSig scheme is constructed by the standard signature scheme, forward secures signature scheme and the aggregate signature scheme. It has an additional property of tamper evidence besides the property of forward secure, which can detect the time period when the key is exposed. In the standard model, the scheme constructed in the paper is proved to satisfy the prop- erties of forward secure, strong forward tamper-evidence secure, and strongly unforgeable under the chosen-message attack.  相似文献   

11.
We discuss the equivalence problem of hyperneutral type nonlinear time varying control system and linear time varying control system in the theory of stabilization. Making use of the symmetric positive definite solution of Riccati matrix differential equation which corresponds to the linear time varying control system, we construct the Lyapunov function. Then we provide the sufficent conditions which make that the zero solution of the hyperneutral type nonlinear time varying control systems is uniformly asymptotically stable by means of the Lyapunov equivalence decomposition method, and find the formulaes which can be used to estimate the bounds of the time delays and the nonlinear terms. Mong Peiyuan: born in 1950, Associate professor Supported by the Natural Science Foundation of Hubei Province Education Committee. Project code: 97A080  相似文献   

12.
Time series analysis and time domain statistics applied to the fault sonic diagnosis of the pressure hammer with artificial diamond is reported. This method with the characters of brief criterion, high accuracy and quick speed is suitable for alarming on the spot. Foundation item: Supported by the National Natural Science Foundation of China Biography: HU Yao-gai (1972-), male, Master, Research interest is in fault diagnosis.  相似文献   

13.
In this paper, we give a necessary and sufficient condition of sequence of nodes, such that, the error of trigonometric interpolation for analytic function converges to 0. Foundation item: Supported by the Science Foundation of SEC of China and Foundation of Wuhan University Biography: LIU Hua (1971-), male, PH. D candidate, Research interest is in complex analysis.  相似文献   

14.
The electron concentration horizontal gradient vector of the ionosphere and its south-north and east-west components over Chongqing station are analyzed and calculated, using the first approximation, time correlation and space correlation and another approach introduced. And then, the validity of the two methods is analyzed and compared. Foundation item: Supported by the National Natural Science Foundation of China (69571020) and the Research Fund for the Doctoral Program of Higher Education (RFDP1999048602) Biography: Chong Yan-wen(1972-), male, Ph. D. candidate, research direction: ionospheric modeling and inversion.  相似文献   

15.
In this paper, based on the theory of parameter estimation, we give a selection method and, in a sense of a good character of the parameter estimation, we think that it is very reasonable. Moreover, we offer a calculation method of selection statistic and an applied example. Foundation item: Supported by the Natural Science Foundation of Anhui Education Committee Biography: Sun Dao-de (1957-), male, associate professor, research interes: theory and applications of mathematical statistics.  相似文献   

16.
We studied the problem of existence of jointly continuous local time for an additive process.Here, “local time” is understood in the sence of occupation density, and by an additive Lévy process we mean a process X={X(t), t∈Rd+)} which has the decomposition X= X1 X2 … XN. We prove that if the product of it slower index and N is greater than d, then a jointly continuous local time can be obtained via Berman's method.  相似文献   

17.
A novel cellulose hydrogel is prepared by regenerating cellulose from its ionic liquid solution. The transparency cellulose hydrogel presents a good chemical stability and an acceptable mechanical property. This non-toxic cellulose hydrogel should be biocompatible and may be useful in the future as a biomaterial. Supported by the National Natural Science Foundation of China (Grant No. 20604017) and Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China  相似文献   

18.
In this paper, we obtain an explicit formula of general solution for a class of the homogeneous recurrence of variable coefficients with two indices. Foundation item: Supported by the National Natural Science Foundation of China(19771063) Biography: YU Chang-an(1948-), male, Professor, Current research interest is in combinatorial theory  相似文献   

19.
In this paper, we generalize an, inequality of meromorphic mappings to quasimeromorphic ones. Applying the results here, we can establish a normal criterion of quasimeromorphic mappings. Foundation item: Supported by the National Natural Science Foundation of China (No. 19871064) Biography: Deng Fang-wen (1974-), male, Ph. D. candidate, research interest: complex analysis.  相似文献   

20.
0 IntroductionXiantaoHanjiangRiverHighwayBridgelocatesonnorth westsuburbofXiantaocity ,crossesovertheHanjiangRiv er.Thecable stayedbridgeisasingle towersystemwiththespansof (5 0 + 82 + 180 )m .Thenon symmetricalstructureisusedheresothatthemainpiercankeepoffthemainchannel.Thesectionofthegirderisnotconstantinorderthatthedeadloadcanbeinbalancealthoughthespansaredifferent.Thedeckwidthis 2 3m (notincludingthewidthofthecablelane) ,laterallayoutisthatofdouble directionfour lanewithoutsidewalk ,b…  相似文献   

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