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1.
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   

2.
Based on the difficulty of solving the ECDLP (elliptic curve discrete logarithm problem) on the finite field, we present a (t, n) threshold signature scheme and a verifiable key agreement scheme without trusted party. Applying a modified elliptic curve signature equation, we get a more efficient signature scheme than the existing ECDSA (ellipticcurve digital signature algorithm) from the computability and security view. Our scheme has a shorter key, faster computation, and better security.  相似文献   

3.
The theory of detecling ridges in the modulus of the continuous wavelet transform is presented as well as reconstructing signal by using information on ridges,To periodic signal we suppose Morlet wavelet as basic wavelet, and research the local extreme point and extrema of the wavelet transform on periodic function for the collection of signal' s instantaneous amplitude and period.  相似文献   

4.
This paper presents a parallel two-level evolutionary algorithm based on domain decomposition for solving function optimization problem containing multiple solutions. By combining the characteristics of the global search and local search in each sub-domain, the former enables individual to draw closer to each optima and keeps the diversity of individuals, while the latter selects local optimal solutions known as latent solutions in sub-domain. In the end, by selecting the global optimal solutions from latent solutions in each sub-domain, we can discover all the optimal solutions easily and quickly. Foundation item: Supported by the National Natural Science Foundation of China (60133010,60073043,70071042) Biography: Wu Zhi-jian(1963-), male, Associate professor, research direction: parallel computing, evolutionary computation.  相似文献   

5.
Investigation on Relationship between Cost and Software Reliability   总被引:1,自引:1,他引:1  
Based on the fact that the software development cost is an important factor to control the whole project, we discuss the relationship between the software development cost and software reliability according to the empirical data collected from the development process. By evolutionary modeling we get an empirical model of the relationship between cost and software reliability, and validate the estimate results with the empirical data.  相似文献   

6.
This paper presents a two-phase genetic algorithm (TPGA) based on the multi-parent genetic algorithm (MPGA). Through analysis we find MPGA will lead the population’s evolvement to diversity or convergence according to the population size and the crossover size, so we make it run in different forms during the global and local optimization phases and then forms TPGA. The experiment results show that TPGA is very efficient for the optimization of low-dimension multi-modal functions) usually we can obtain all the global optimal solutions. Foundation item: Supported by the National Natural Science Foundation of China (70071042, 60073043,60133010) Biography: Huang Yu-zhen ( 1977-), female, Master candidate, research direction; evolution computation.  相似文献   

7.
To overcome the drawbacks such as high computational cost, unreasonable security model and long signature length in existing certificateless ring signature schemes, we propose an efficient certificateless ring signature scheme in this paper. Our construction is inspired by some efficient ID-based ring signature schemes, and uses bilinear pairings as a basic tool. Using a reasonable security model, the unforgeability of the proposed scheme is proven based on the intractability of the computational Diffie-Hellman (CDH) problem. The signature length of the new scheme is only |G2|+n|G1| (|Gi| is the bit length of an element in group Gi, i =1, 2). Compared with other existing certificateless ring signature schemes, the newly proposed scheme has a shorter signature length and is more efficient and practical.  相似文献   

8.
Chinese Postman Problem is an unsettled graphic problem. It was approached seldom by evolutionary computation. Now we use genetic algorithm to solve Chinese Postman Problem in undirected graph and get good results. It could be extended to solve Chinese postman problem in directed graph. We make these efforts for exploring in optimizing the mixed Chinese postman problem. Foundation item: Supported by the National Natural Science Foundation of China (60133010, 70071042) Biography: Jiang Hua(1974-), male, Master candidate, research direction: Evolutionary computation.  相似文献   

9.
我国在建设社会主义市场经济价值系统的过程中,可以借鉴和扬弃西方“个性主义“的普遍人类价值因素.在社会层面,借鉴吸收卢梭关于“自由个人构成合理共同体“的思想,克服旧价值观“整体主义“泯灭个性自由的痼疾;在政治层面,借鉴吸取洛克“社会契约论“的民主法制精神,消解旧价值观以“权威主义“剥夺个人主体地位的顽症;在伦理层面,借鉴吸收康德“绝对命令说“的道德精髓,清除旧价值观以“私德至上“否绝个人正当利益的弊端.目前,我们应当看到“个性主义“因其阶级性时代性所限,有可能导致个人主体性的异化,滑向极端利己主义,对此,只能以马克思关于“个人与社会统一为本位“的“人类解放“价值观对其补偏纠弊.  相似文献   

10.
In this paper, we point out that Libert and Quisquater‘s signeryption scheme cannot provide public verifiability. Then we present a new identity based signcryption scheme using quadratic residue and pairings over elliptic curves. It combines the functionalities of both public verifiability and forward security at the same time. Under the Bilinear Diffie-Hellman and quadratic residue assumption, we describe the new scheme that is more secure and can be some what more efficient than Libert and Quisquater‘s one.  相似文献   

11.
The paper presents the embedded real-time software-oriented requirements engineering environment—SREZ. It involves the whole process of software requirements engineering, including the definition, analysis and checking of requirements ,specifications. We first explain the principles of the executable specification language RTRSM. Subsequently, we introduce the main functions of SREE, illustrate the methods and techniques of checking requirements specifications, especially how to perform simulation execution, combining prototyping method with RTRSM and animated representations. At last, we compare the SREE with other requirements specifications methods and make a summary for SREE's advantages.  相似文献   

12.
In the case study in Agricultural Area of Tibet, the process and characteristics of farmers‘ land use were surveyed by semi-structural interview questionnaire. By comparing the change of land covers and farmers‘ land decision in two periods, the spatial connection of them was obtained. And the relations among farmers‘ land decision, land use change and environment were examined by calculating emergy and value flow. The results show that: hunting the maximal profits is the primary aim of farmers‘ land decisions farmers‘ land decision is incompatible with sustainable land use presently; farmers‘ land decision and land cover can be embodied spatially by each others the change of farmers‘ land decision can be monitored by observing the change of land cover, and the sustainability of farmers‘ land decision can be appraised by calculating emergy and value flow.  相似文献   

13.
Current distributed parallel file systems and database systems can not satisfy the demands of data-intensive applications, such as storage capacity, access performance, reliability, scalability, and so on. Cluster-based storage sys tems have some shortcomings, too. To solve this kind of problems, a novel PC storage cluster solution is proposed, a distributed storage system based on 3-tiered agent architecture is designed, the system reliability model based on the masterslave backup mode is built, and the system availability is analyzed with the Markov model. According to the system availability formula and the values of the system parameters, the novel system can provide higher reliability and availability to satisfy users' requirements,  相似文献   

14.
We introduced a new method—duration Hidden Markov Model (dHMM) to predicate the secondary structure of Protein. In our study, we divide the basic second structure of protein into three parts: H (α-Helix), E (β-sheet) and O (others, include coil and turn). HMM is a kind of probabilistic model which more thinking of the interaction between adjacent amino acids (these interaction were represented by transmit probability), and we use genetic algorithm to determine the model parameters. After improving on the model and fixed on the parameters of the model, we write a program HMMPS. Our example shows that HMM is a nice method for protein secondary structure prediction. Foundation item: Supported by the National Natural Science Foundation of China (30170214) Biography: Huang Jing (1977-), female, Master candidate, research direction: bioinformatics.  相似文献   

15.
采准巷道支护结构最优可靠度的确定   总被引:1,自引:0,他引:1  
用半理论半经验的方法对采准巷道支护结构造价及损失期望作了详细推导与分析,并由此得出支护结构最优可靠度的确定方法,为最后进行支护参数的设计打下了基础,并为矿业工作者降低地下采准工程成本提供了新的思路。  相似文献   

16.
We propose an efficient multicast source authentication protocol called efficient multi-tree-chains scheme (EMTC), which shows more loss resistibility, less communication cost, and no delay at receivers. The EMTC scheme is based on combination of single Chain scheme and Hash Tree Chains scheme, and integrates the advantages of both. In this scheme, stream is firstly divided into blocks with n packets, and each block consists of m clusters, everyone of which contains a tree of packets. All clusters are chained together. Through EMTC, packets of one cluster can be authenticated by any packet of the previous cluster. Compared to other multicast authentication protocols, the proposed scheme has the following advantages: ① dramatically improves the resistance to burst packets loss; ② low computation and communication overhead; ③ imposes low delay on the sender side and no delay on the receiver side.  相似文献   

17.
ID-based public key cryptosystem can be a good alternative for certifieate-based public key setting. This paper provides an efficient ID-based proxy multi signature scheme from pairings. In the random oracle model, we prove that our new scheme is secure against existential delegation forgery with the assumption that Hess's scheme-1 is existential unforgeable, and that our new scheme is secure against existential proxy multi-signature forgery under the hardness assumption of the computational Diffie-Hellman problem.  相似文献   

18.
We study the number of k-cycles in a random graph G(n, p). We estimate the probability that a random graph contains more k-cycles than expected. In this case, the usual martingale inequality with bounded difference is not effective. By constructing a variable that approximates to the number of k-cycles in a random graph and using a new and extensive martingale inequality, we get the results in this paper. Foundation item: Supported by the National Natural Science Foundation of China (10571139)  相似文献   

19.
Whitman K  Starfield AM  Quadling HS  Packer C 《Nature》2004,428(6979):175-178
In most species, sport hunting of male trophy animals can only reduce overall population size when the rate of removal of males is so high that females can no longer be impregnated. However, where males provide extensive paternal care, the removal of even a few individuals could harm the population as a whole. In species such as lions, excessive trophy hunting could theoretically cause male replacements (and associated infanticide) to become sufficiently common to prevent cubs reaching adulthood. Here we simulate the population consequences of lion trophy hunting using a spatially explicit, individual-based, stochastic model parameterized with 40 years of demographic data from northern Tanzania. Although our simulations confirm that infanticide increases the risk of population extinction, trophy hunting could be sustained simply by hunting males above a minimum age threshold, and this strategy maximizes both the quantity and the quality of the long-term kill. We present a simple non-invasive technique for estimating lion age in populations lacking long-term records, and suggest that quotas would be unnecessary in any male-only trophy species where age determination could be reliably implemented.  相似文献   

20.
研究面向单个云的虚拟机群,以最小化任务响应时间和资源损耗代价为优化目标,提出基于遗传算法的负载均衡优化算法.所提算法实现了自适应的变异概率,并且可以根据用户任务的实际需求动态地调整系统响应时间和资源损耗在整个优化过程中所占的比重.模拟仿真结果表明,该算法不仅能够满足用户需求,而且能够获得较高的资源利用率.  相似文献   

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