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51.
将人工智能技术应用于管理信息系统(MIS)使其具备某些智能特征,这是目前计算机应用领域的重要研究内容之一。本文将决策表技术引入管理信息系统作为知识存贮手段,用户可通过决策表自行设置规则集,并用推理机进行演绎推理,从而实现对管理信息系统数据库的智能查询。该系统的原型已在 IBM PC/286上实现。本文讨论它的设计思想和实现技术,并给出一个简单的查询实例。 相似文献
52.
A framework for positive dependence 总被引:4,自引:3,他引:1
George Kimeldorf Allan R. Sampson 《Annals of the Institute of Statistical Mathematics》1989,41(1):31-45
This paper presents, for bivariate distributions, a unified framework for studying and relating three basic concepts of positive dependence. These three concepts are positive dependence orderings, positive dependence properties and measures of positive dependence. The latter two concepts are formally defined and their properties discussed. Interrelationships among these three concepts are given, and numerous examples are presented.Supported by the National Science Foundation under Grant DMS-8301361.Supported by the Air Force Office of Scientific Research under Contract 84-0113. Reproduction in whole or part is permitted for any purpose of the United States Government. 相似文献
53.
V. A. Belonogov 《Algebra and Logic》2005,44(1):13-24
In the representation theory of symmetric groups, for each partition of a natural number n, the partition h() of n is defined so as to obtain a certain set of zeros in the table of characters for Sn. Namely, h() is the greatest (under the lexicographic ordering ) partition among P(n) such that (g) 0. Here, is an irreducible character of Sn, indexed by a partition , and g is a conjugacy class of elements in Sn, indexed by a partition . We point out an extra set of zeros in the table that we are dealing with. For every non self-associated partition P(n), the partition f() of n is defined so that f() is greatest among the partitions of n which are opposite in sign to h() and are such that (g) 0 (Thm. 1). Also, for any self-associated partition of n > 1, we construct a partition
() P(n) such that
() is greatest among the partitions of n which are distinct from h() and are such that (g) 0 (Thm. 2).Supported by RFBR grant No. 04-01-00463 and by RFBR-BRFBR grant No. 04-01-81001.Translated from Algebra i Logika, Vol. 44, No. 1, pp. 24–43, January–February, 2005. 相似文献
54.
介绍了一种正电子发射断层成像术实时查找表电路。该电路接收符合电路输出的位置信号和能量信号,用查表的方法完成重心法中的除法运算,然后再第二次查表得到该γ光子所入射到的晶格的离散化坐标值和能量阈值,并完成能量甄别以剔除部分散射事件。此外,该电路还结合了呼吸门控和心电门控功能。查找表存储在flash器件中,由CPLD控制读写。本设计的特点是利用硬件电路来完成查找表功能,效率更高,每次事件的查表寻址的延迟时间小于100ns,并且可以在线更新查找表的内容,使用方便。另外,还说明了用CPLD来读写NORflash的方法,以及该电路与系统中其它模块间的数据通信方法。 相似文献
55.
In this paper,we apply cellular automata rules,which can be given by a truth table,to human memory.We design each memory as a tracking survey mode that keeps the most recent three opinions.Each cellular automata rule,as a personal mechanism,gives the final ruling in one time period based on the data stored in one’s memory.The key focus of the paper is to research the evolution of people’s attitudes to the same question.Based on a great deal of empirical observations from computer simulations,all the rules can be classified into 20 groups.We highlight the fact that the phenomenon shown by some rules belonging to the same group will be altered within several steps by other rules in different groups.It is truly amazing that,compared with the last hundreds of presidential voting in America,the eras of important events in America’s history coincide with the simulation results obtained by our model. 相似文献
56.
Structures of table algebras determined by their character tables are studied in [6]. In this paper we continue the research in this direction. In particular, we investigate the conditions under which the character table with a zero submatrix yields a generalized wreath product for a commutative table algebra. Applications to finite groups are also discussed, and some new and known results are obtained as direct consequences. 相似文献
57.
58.
We propose a new model – we call it a smoothed threshold life table (STLT) model – to generate life tables incorporating information on advanced ages. Our method allows a smooth mortality transition from non-extreme to extreme ages, and provides objectively determined highest attained ages with which to close the life table.We proceed by modifying the threshold life table (TLT) model developed by Li et al. (2008). In the TLT model, extreme value theory (EVT) is used to make optimal use of the relatively small number of observations at high ages, while the traditional Gompertz distribution is assumed for earlier ages. Our novel contribution is to constrain the hazard function of the two-part lifetime distribution to be continuous at the changeover point between the Gompertz and EVT models. This simple but far-reaching modification not only guarantees a smooth transition from non-extreme to extreme ages, but also provides a better and more robust fit than the TLT model when applied to a high quality Netherlands dataset. We show that the STLT model also compares favourably with other existing methods, including the Gompertz–Makeham model, logistic models, Heligman–Pollard model and Coale–Kisker method, and that a further generalisation, a time-dependent dynamic smooth threshold life table (DSTLT) model, generally has superior in-sample fitting as well as better out-of-sample forecasting performance, compared, for example, with the Cairns et al. (2006) model. 相似文献
59.
An adjustable approach to fuzzy soft set based decision making 总被引:2,自引:0,他引:2
Molodtsov’s soft set theory was originally proposed as a general mathematical tool for dealing with uncertainty. Recently, decision making based on (fuzzy) soft sets has found paramount importance. This paper aims to give deeper insights into decision making based on fuzzy soft sets. We discuss the validity of the Roy-Maji method and show its true limitations. We point out that the choice value designed for the crisp case is no longer fit to solve decision making problems involving fuzzy soft sets. By means of level soft sets, we present an adjustable approach to fuzzy soft set based decision making and give some illustrative examples. Moreover, the weighted fuzzy soft set is introduced and its application to decision making is also investigated. 相似文献
60.
Miriam Cohen 《代数通讯》2013,41(12):4618-4633
We extend the notion of conjugacy classes and class sums from finite groups to semisimple Hopf algebras and show that the conjugacy classes are obtained from the factorization of H as irreducible left D(H)-modules. For quasitriangular semisimple Hopf algebras H, we prove that the product of two class sums is an integral combination of the class sums up to d ?2 where d = dim H. We show also that in this case the character table is obtained from the S-matrix associated to D(H). Finally, we calculate explicitly the generalized character table of D(kS 3), which is not a character table for any group. It moreover provides an example of a product of two class sums which is not an integral combination of class sums. 相似文献