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991.
Lie‐Fern Hsu 《Quality and Reliability Engineering International》2007,23(2):269-272
He and Grigoryan (Quality and Reliability Engineering International 2002; 18 :343–355) formulated the design of a double‐sampling (DS) s control chart as an optimization problem and solved it with a genetic algorithm. They concluded that the DS s control charts can be a more economically preferable alternative in detecting small shifts than traditional s control charts. We explain that, since they only considered the average sample size when the process is in control, their conclusion is questionable. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
992.
A. V. Adel'shin 《Automation and Remote Control》2004,65(3):388-395
Problems of the maximum and the minimum satisfiability on the basis of the integer linear programming and L-partition are studied. The L-structure of polyhedrons of the problems is investigated. Families are set up of unweighted problems of the maximum and the minimum satisfiability, the powers of L-coverings of which grow exponentially with an increase in the number of variables in a formula. 相似文献
993.
A quantitative study of firewall configuration errors 总被引:1,自引:0,他引:1
The protection that firewalls provide is only as good as the policy they are configured to implement. Analysis of real configuration data show that corporate firewalls are often enforcing rule sets that violate well established security guidelines. Firewalls are the cornerstone of corporate intranet security. Once a company acquires a firewall, a systems administrator must configure and manage it according to a security policy that meets the company's needs. Configuration is a crucial task, probably the most important factor in the security a firewall provides. 相似文献
994.
Tomer A. Goldin L. Kuflik T. Kimchi E. Schach S.R. 《IEEE transactions on pattern analysis and machine intelligence》2004,30(9):601-612
We propose a model that enables software developers to systematically evaluate and compare all possible alternative reuse scenarios. The model supports the clear identification of the basic operations involved and associates a cost component with each basic operation in a focused and precise way. The model is a practical tool that assists developers to weigh and evaluate different reuse scenarios, based on accumulated organizational data, and then to decide which option to select in a given situation. The model is currently being used at six different companies for cost-benefit analysis of alternative reuse scenarios; we give a case study that illustrates how it has been used in practice. 相似文献
995.
996.
In this note, the input-output linearization problem (IOLP) for a class of single-input-single-output nonlinear systems with multiple delays in the input, the output, and the state is studied. The problem is solved by means of various static or dynamic compensators, including state and output feedback. The mathematical setting is based on some noncommutative algebraic tools and the introduction of a nonlinear version of the so-called Roesser models for this class of systems. These are claimed to be the cornerstones for studying nonlinear time-delay systems. Necessary and sufficient conditions are given for the existence of a static or pure shift output feedback which solves the IOLP. Sufficient conditions for the existence of a dynamic state feedback solution are included as well. 相似文献
997.
In this note, simple symmetric interval bounds on the singular values of a matrix based on its Gershgorin disks are proposed. This allows the Gershgorin theorem to be used not only to provide information about the location of the eigenvalues of a matrix but also its singular values. This is utilized for the proposition of a new design technique for singular value loop shaping based on the diagonal dominance methodology for design of linear multivariable plants. In return, this allows multiple-channel simply structured controllers to be designed with a view to robustness and to meet constraints and specifications on the behavior of its singular values. A design example is given demonstrating the effectiveness of this approach. 相似文献
998.
Nonlinear control synthesis by convex optimization 总被引:3,自引:0,他引:3
A stability criterion for nonlinear systems, recently derived by the third author, can be viewed as a dual to Lyapunov's second theorem. The criterion is stated in terms of a function which can be interpreted as the stationary density of a substance that is generated all over the state-space and flows along the system trajectories toward the equilibrium. The new criterion has a remarkable convexity property, which in this note is used for controller synthesis via convex optimization. Recent numerical methods for verification of positivity of multivariate polynomials based on sum of squares decompositions are used. 相似文献
999.
We consider probability-theoretic and statistical models and methods for computing the characteristics of dictionary structures. Results of a statistical analysis of several commonly used dictionaries are presented in order to test the adequacy of the computing methods proposed. 相似文献
1000.
S. M. Obraztsov G. A. Birzhevoi Yu. V. Konobeev V. A. Solov'ev O. S. Silkina 《Atomic Energy》2004,96(2):111-116
The results of a computational experiment with a neural-net model simulating the effect of the chemical composition on the plastic properties of ÉP-450 steel are presented. It is shown that computer-aided development of reactor steel with prescribed properties is, in principle, possible. 相似文献