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971.
模糊推理全蕴涵算法及其还原性 总被引:15,自引:0,他引:15
模糊推理是模糊控制的逻辑基础,然而通用的模糊推理CRI算法却缺乏严格的逻辑依据,近期问世的模糊推理全蕴涵三I算法有效地改进了CRI算法。本文研究了全蕴涵三I算法的一般计算公式及其还原性问题,并且得到了一些新的算法,也提出了一些新的观点,文献中已有的结果大多数是本文结果的特例。从而为模糊推理提供了一种新方法。 相似文献
972.
The numerical solution of elliptic selfadjoint second-order boundary value problems leads to a class of linear systems of equations with symmetric, positive definite, large and sparse matrices which can be solved iteratively using a preconditioned version of some algorithm. Such differential equations originate from various applications such as heat conducting and electromagnetics. Systems of equations of similar type can also arise in the finite element analysis of structures. We discuss a recursive method constructing preconditioners to a symmetric, positive definite matrix. An algebraic multilevel technique based on partitioning of the matrix in two by two matrix block form, approximating some of these by other matrices with more simple sparsity structure and using the corresponding Schur complement as a matrix on the lower level, is considered. The quality of the preconditioners is improved by special matrix polynomials which recursively connect the preconditioners on every two adjoining levels. Upper and lower bounds for the degree of the polynomials are derived as conditions for a computational complexity of optimal order for each level and for an optimal rate of convergence, respectively. The method is an extended and more accurate algebraic formulation of a method for nine-point and mixed five- and nine-point difference matrices, presented in some previous papers. 相似文献
973.
Ken-Ichi Baba Masayuki Murata Hideo Miyahara 《International Journal of Communication Systems》1994,7(4):283-294
Broadband ISDN (integrated services digital network) should provide various kinds of communication services for multimedia traffic, including voice, computer data, still picture and motion video, and an ATM (asynchronous transfer mode) technology is expected to satisfy those demands. In ATM networks, a VP (virtual path) concept is introduced for simplifying the network resource management. However, if the bandwidth of each VP is fixed, it cannot absorb traffic load fluctuation. In this case, it is likely to happen that one VP has no remaining bandwidth while other VPs on the same physical link have free capacities. Another extremity is that a VP is not introduced, and that all VCs along the same physical link share the whole bandwidth of the link. This can achieve an efficient use of the link, but it apparently requires complicated call set-up procedures. In this paper, we propose a new dynamic VP bandwidth control method, in which the bandwidth allocated to each VP is dynamically changed according to traffic fluctuation. More specifically, in the case that multiple VPs are multiplexed on the same link between two nodes, when the utilization of some VP is increased, that VP requests an additional bandwidth. When the traffic load becomes low and the utilization of a VP is decreased, a part of the assigned bandwidth is released. We consider two methods for this purpose; one is the basic method in which the bandwidth increase request is issued after the VP bandwidth is exhausted. The other is the look-ahead method where the bandwidth increase is requested in advance before the bandwidth starvation. An approximate analysis for the above methods is provided, and the validation of its accuracy is assessed by comparing with simulation results. Through numerical examples, we show that our methods can provide performance improvement in terms of call loss probabilities of each VP. 相似文献
974.
GEVREY CLASS REGULARITY AND APPROXIMATE INERTIAL MANIFOLDS FOR THE NEWTON-BOUSSINESQ EQUATIONS 总被引:2,自引:0,他引:2
§1.IntroductionApproximateinertialmanifoldsarerelatedtothestudyoflongtimebehaviourofsolutionsofdisipativepartialdiferentialeq... 相似文献
975.
本文提出了一种称为近似逻辑的逻辑系统,该系统不仅具有模糊的逻辑值,其逻辑运算符也为模糊的.近似逻辑很适合描述神经网络.基于这种逻辑我们定义了一种神经网络模型.该模型可以学习和存储知识.基于这种神经网络模型,开发了一个多专家意见综合系统. 相似文献
976.
用Foster-Boys的定域化准则讨论了EHMO方法的分子轨道定域化问题,提出用双中心重叠积分近似计算双中心轨道偶极矩积分方法,得到的EHMO定域分子轨道与严格定域化结果接近,与从头计算方法的定域化结果定性一致。 相似文献
977.
Bjørn Voigt 《Theoretical chemistry accounts》1973,31(4):289-295
A series of approximate LCAO-SCF methods intermediate between the INDO and the NDDO schemes is proposed. The suggestion is based upon the decomposition of integrals in multipole-multipole type interactions. 相似文献
978.
Nazakat Ullah 《Pramana》1982,18(2):211-214
An approximation procedure is described to calculate the projected energies from an intrinsicrpa hf wave function. The method of moments is used to find the relevant parameters. A model calculation is carried out for illustrative
purposes. 相似文献
979.
模糊自适应估计器在INS/GPS组合导航中的应用研究 总被引:2,自引:0,他引:2
研究了一种模糊自适应神经网络状态估计器的工作原理及结构,并讨论了用其代替传统扩展卡尔曼滤波在导航参数估计中的实现方法。利用扩展卡尔曼滤波来构造模糊推理系统,通过神经网络对模糊推理系统进行训练,根据输入输出样本自动调整模糊系统的设计参数,从而实现对INS/GPS组合导航系统导航参数的最优估计。通过仿真验证表明,用模糊自适应状态估计方法进行导航系统的初始对准,能够大大提高系统的实时性。 相似文献
980.
陆基无线电导航系统中,所有关键设备和关键工作单元都分布在各个导航台站。要全面监控导航系统,需要重点监控导航台的关键导航设备和设备环境状态。首先介绍了监控系统的原理,进而针对导航系统本身的特点,重点讨论了系统的需求分析、总体设计、详细设计、具体的实施考虑、外部条件的处理策略和系统的扩展性。最后,根据技术发展趋势和系统要求,展望了智能化导航监控系统的发展方向。 相似文献