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51.
Li-Vang Lozada-Chang 《Information Sciences》2011,181(11):2340-2355
In this paper, we introduce a mathematical model for analyzing the dynamics of the univariate marginal distribution algorithm (UMDA) for a class of parametric functions with isolated global optima. We prove a number of results that are used to model the evolution of UMDA probability distributions for this class of functions. We show that a theoretical analysis can assess the effect of the function parameters on the convergence and rate of convergence of UMDA. We also introduce for the first time a long string limit analysis of UMDA. Finally, we relate the results to ongoing research on the application of the estimation of distribution algorithms for problems with unitation constraints. 相似文献
52.
Flash memory efficient LTL model checking 总被引:1,自引:0,他引:1
S. EdelkampD. Sulewski J. BarnatL. Brim P. Šime?ek 《Science of Computer Programming》2011,76(2):136-157
As the capacity and speed of flash memories in form of solid state disks grow, they are becoming a practical alternative for standard magnetic drives. Currently, most solid-state disks are based on NAND technology and much faster than magnetic disks in random reads, while in random writes they are generally not.So far, large-scale LTL model checking algorithms have been designed to employ external memory optimized for magnetic disks. We propose algorithms optimized for flash memory access. In contrast to approaches relying on the delayed detection of duplicate states, in this work, we design and exploit appropriate hash functions to re-invent immediate duplicate detection.For flash memory efficient on-the-fly LTL model checking, which aims at finding any counter-example to the specified LTL property, we study hash functions adapted to the two-level hierarchy of RAM and flash memory. For flash memory efficient off-line LTL model checking, which aims at generating a minimal counterexample and scans the entire state space at least once, we analyze the effect of outsourcing a memory-based perfect hash function from RAM to flash memory.Since the characteristics of flash memories are different to magnetic hard disks, the existing I/O complexity model is no longer sufficient. Therefore, we provide an extended model for the computation of the I/O complexity adapted to flash memories that has a better fit to the observed behavior of our algorithms. 相似文献
53.
Loren Paul ReesAuthor VitaeJason K. DeaneAuthor Vitae Terry R. RakesAuthor VitaeWade H. BakerAuthor Vitae 《Decision Support Systems》2011,51(3):493-505
Security countermeasures help ensure the confidentiality, availability, and integrity of information systems by preventing or mitigating asset losses from Cybersecurity attacks. Due to uncertainty, the financial impact of threats attacking assets is often difficult to measure quantitatively, and thus it is difficult to prescribe which countermeasures to employ. In this research, we describe a decision support system for calculating the uncertain risk faced by an organization under cyber attack as a function of uncertain threat rates, countermeasure costs, and impacts on its assets. The system uses a genetic algorithm to search for the best combination of countermeasures, allowing the user to determine the preferred tradeoff between the cost of the portfolio and resulting risk. Data collected from manufacturing firms provide an example of results under realistic input conditions. 相似文献
54.
基于FPGA的高速自适应滤波器的实现 总被引:2,自引:0,他引:2
在LMS算法进行变步长处理的基础上,结合驰豫超前流水线技术和时序重构技术提出了创新结构和改进算法,在FPGA的仿真综合环境中设计实现了该高速自适应滤波器,并且在AlteraDE2-70开发板上进行了板级测试。 相似文献
55.
There are several numerical methods for calculation of electric fields but they need some sort of experience and trial and error to get the correct solution. A genetic algorithm (GA) based approach is used to eliminate the need for the experience and to save time and effort spent in the trial and error. Two enhancement techniques, namely, Refreshment Method and No-Twins Method, are used with the GA operators to improve the performance of the GA in assessment of high voltage fields. The performance of these two enhancement techniques has been studied for computing the electrostatic field in high voltage applications. 相似文献
56.
用于半自动视频对象提取的自适应网格图像分割 总被引:3,自引:0,他引:3
随着MPEG-4标准的发展和基于内容的视频处理研究,视频对象平面(VOP)的有效产生成为一个关键问题。本文提出一种基于区域的自适应网格彩色图像分割方法,可用于获得半自动视频对象跟踪和提取所需的初始VOP。该方法利用CIE L*a*b*色彩空间的特征量,对视频序列的第一帧进行三角形网格的分裂与合并。对MPEG-4标准测试序列的分割实验取得了较好的结果。 相似文献
57.
Genetic adaptive state estimation 总被引:1,自引:0,他引:1
James R. Gremling Kevin M. Passino 《Engineering Applications of Artificial Intelligence》2000,13(6):611-623
A genetic algorithm (GA) uses the principles of evolution, natural selection, and genetics to offer a method for parallel search of complex spaces. This paper describes a GA that can perform on-line adaptive state estimation for linear and nonlinear systems. First, it shows how to construct a genetic adaptive state estimator where a GA evolves the model in a state estimator in real time so that the state estimation error is driven to zero. Next, several examples are used to illustrate the operation and performance of the genetic adaptive state estimator. Its performance is compared to that of the conventional adaptive Luenberger observer for two linear system examples. Next, a genetic adaptive state estimator is used to predict when surge and stall occur in a nonlinear jet engine. Our main conclusion is that the genetic adaptive state estimator has the potential to offer higher performance estimators for nonlinear systems over current methods. 相似文献
58.
59.
Effective on-line algorithms for reliable due date quotation and large-scale scheduling 总被引:1,自引:0,他引:1
We consider the sequencing of a series of jobs that arrive at a single processor over time. At each job’s arrival time, a
due date must be quoted for the job, and the job must complete processing before its quoted due date. The objective is to
minimize the sum (or average) of quoted due dates, or equivalently, the average quoted lead time. In this paper, we propose
on-line heuristics for this problem and characterize the conditions under which these heuristics are asymptotically optimal.
Computational testing further demonstrates the relative effectiveness of these heuristics under various conditions.
Both authors made equal contributions to this paper and are listed in alphabetical order. 相似文献
60.
Ian Flood 《Advanced Engineering Informatics》2008,22(1):4-14
The purpose of this paper is to stimulate interest within the civil engineering research community for developing the next generation of applied artificial neural networks. In particular, it identifies what the next generation of these devices needs to achieve, and provides direction in terms of how their development may proceed. An analysis of the current situation indicates that progress in the development of artificial neural network applications has largely stagnated. Suggestions are made for advancing the field to the next level of sophistication and application, using genetic algorithms and related techniques. It is shown that this approach will require the design of some very sophisticated genetic coding mechanisms in order to develop the required higher-order network structures, and will utilize development mechanisms observed in nature such as growth, self-organization, and multi-stage objective functions. The capabilities of such an approach and the way in which they can be achieved are explored with reference to the problems of: (a) determining truck attributes from the strain envelopes they induce in structural members when crossing a bridge, and; (b) developing a decision support system for dynamic control of industrialized manufacturing of houses. 相似文献