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21.
22.
For neural networks with all the parameters unknown, we focus on the global robust synchronization between two coupled neural networks with time-varying delay that are linearly and unidirectionally coupled. First, we use Lyapunov functionals to establish general theoretical conditions for designing the coupling matrix. Neither symmetry nor negative (positive) definiteness of the coupling matrix are required; under less restrictive conditions, the two coupled chaotic neural networks can achieve global robust synchronization regardless of their initial states. Second, by employing the invariance principle of functional differential equations, a simple, analytical, and rigorous adaptive feedback scheme is proposed for the robust synchronization of almost all kinds of coupled neural networks with time-varying delay based on the parameter identification of uncertain delayed neural networks. Finally, numerical simulations validate the effectiveness and feasibility of the proposed technique. 相似文献
23.
On the use of fuzzy inference techniques in assessment models: part I—theoretical properties 总被引:2,自引:0,他引:2
An assessment model is a mathematical model that produces a measuring index, either in the form of a numerical score or a
category to a situation/object, with respect to the subject of measure. From the numerical score, decision can be made and
action can be taken. To allow valid and useful comparisons among various situations/objects according to their associated
numerical scores to be made, the monotone output property and the output resolution property are essential in fuzzy inference-based
assessment problems. We investigate the conditions for a fuzzy assessment model to fulfill the monotone output property using
a derivative approach. A guideline on how the input membership functions should be tuned is also provided. Besides, the output
resolution property is defined as the derivative of the output of the assessment model with respect to its input. This derivative
should be greater than the minimum resolution required. From the derivative, we suggest improvements to the output resolution
property by refining the fuzzy production rules. 相似文献
24.
Management review of the quality-management system is an item in many quality standards and a requirement of the ISO 9001:2000
standard and of laboratory standards ISO 15189 and ISO 17125, and others. These reviews are conducted to ensure that the top
management is informed and involved in the quality-management system with respect to continuing adequacy and effectiveness,
and opportunities for improvement of the system. The management review is a process that should be conducted and audited utilizing
the process approach. A process approach is defined as “An activity using resources and managed in order to enable the transformation
of inputs into outputs” (ISO 9001:2000). All identified main processes in the quality system should be monitored through data
collection by appropriate methods, assuring that data are valid, representative, and adequate. For management review data
must be collected and presented in an accessible form so that processes can be evaluated according to objectives, goals, resources,
etc. On the basis of this information the laboratory management makes the necessary decisions and ensure that actions are
taken that improve the effectiveness of the quality-management system. As output from the management review process, there
should be evidence of decisions regarding: change of quality policy and objectives; plans and possible actions for improvements;
corrective actions as appropriate; increased customer satisfaction; and planning of resources needs. Identification of the
processes involved and using the process approach in the management review ensures the continual improvement of the quality
system.
Presented at the conference Quality in the Spotlight, March 2006, Antwerp, Belgium. 相似文献
25.
In this paper we study the economic lot sizing problem with cost discounts. In the economic lot sizing problem a facility faces known demands over a discrete finite horizon. At each period, the ordering cost function and the holding cost function are given and they can be different from period to period. There are no constraints on the quantity ordered in each period and backlogging is not allowed. The objective is to decide when and how much to order so as to minimize the total ordering and holding costs over the finite horizon without any shortages. We study two different cost discount functions. The modified all-unit discount cost function alternates increasing and flat sections, starting with a flat section that indicates a minimum charge for small quantities. While in general the economic lot sizing problem with modified all-unit discount cost function is known to be NP-hard, we assume that the cost functions do not vary from period to period and identify a polynomial case. Then we study the incremental discount cost function which is an increasing piecewise linear function with no flat sections. The efficiency of the solution algorithms follows from properties of the optimal solution. We computationally test the polynomial algorithms against the use of CPLEX. 相似文献
26.
27.
通过开发实例介绍了在Delphi5 .0中利用虚拟设备驱动程序进行动态加载 ,实现与并行采集卡通讯的技术方法 . 相似文献
28.
29.
The main purpose of this work is to set up the explicit matrix framework appropriate to three-dimensional partial differential
equations by means of the incremental unknowns method. Multilevel schemes of the incremental unknowns are presented in the
three space dimensions, and through numerical experiments, we confirm that the incremental unknowns method is efficient and
the hierarchical preconditioning based on the incremental unknowns can be applied in a more general form.
相似文献
30.
Robust output feedback stabilization for two-dimensional continuous systems in roesser form 总被引:1,自引:0,他引:1
James Lam Shengyuan Xu Yun Zou Zhiping Lin K. Galkowski 《Applied Mathematics Letters》2004,17(12):81-1341
This paper considers the problem of robust stabilization via dynamic output feedbackcontrollers for uncertain two-dimensional continuous systems described by the Roesser's state space model. The parameter uncertainties are assumed to be norm-bounded appearing in all the matrices of the system model. A sufficient condition for the existence of dynamic output feedback controllers guaranteeing the asymptotic stability of the closed-loop system for all admissible uncertainties is proposed. A desired dynamic output feedback controller can be constructed by solving a set of linear matrix inequalities. Finally, an illustrative example is provided to demonstrate the applicability and effectiveness of the proposed method. 相似文献