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111.
Herman Dishkant 《Fuzzy Sets and Systems》1981,5(2):141-147
A logical approach to fuzzy sets method originated by Giles is developed. The infinitely many-valued logic tω is taken as basic. We accept, it is correct to use the strong conjunction by the logical analysis of the summation of fuzzy items. Under some broad conditions it is proved. that the sum of many fuzzy variables is a variable whose membership function is approximately equal to , where a and c are some constant parameters. A method of estimation of the unknown parameters is developed in a general case. The proposed fuzzy method coincides with the method of maximum likelihood if used in problems of classical mathematical statistics. 相似文献
112.
Kenji Tokuo 《International Journal of Theoretical Physics》2004,43(12):2461-2481
113.
Lutz Mattner 《Probability Theory and Related Fields》2004,130(2):151-166
This is a contribution to the theory of sums of independent random variables at an algebraico-analytical level: Let Prob denote the convolution semigroup of all probability measures on with all moments finite, topologized by polynomially weighted total variation. We prove that the cumulant sequence regarded as a function from Prob into the additive topological group ofall real sequences, is universal among continuous homomorphisms from Prob into Hausdorff topological groups, in the usual sense that every other such homomorphism factorizes uniquely through . An analogous result, referring to just the first cumulants,holds for the semigroup of all probability measures with existing rth moments. In particular, there is no nontrivial continuous homomorphism from the convolution semigroup of all probability measures, topologized by the total variation metric, into any Hausdorff topological group.Mathematics Subject Classification (2000): 60B15, 60E10, 60G50 相似文献
114.
Radosav?Dordevi? Miodrag? Ra?kovi? Zoran?Ognjanovi?Email author 《Archive for Mathematical Logic》2004,43(4):557-563
A propositional logic is defined which in addition to propositional language contains a list of probabilistic operators of the form Ps (with the intended meaning the probability is at least s). The axioms and rules syntactically determine that ranges of probabilities in the corresponding models are always finite. The completeness theorem is proved. It is shown that completeness cannot be generalized to arbitrary theories.This research was supported by Ministarstvo za nauku, tehnologije i razvoj Republike Srbije, through Matematiki institut, under grant 1379Mathematics Subject Classification (2000): 03C70, 03B48 相似文献
115.
Cornelius Greither Xavier-Franç ois Roblot Brett A. Tangedal. 《Mathematics of Computation》2004,73(245):297-315
As a starting point, an important link is established between Brumer's conjecture and the Brumer-Stark conjecture which allows one to translate recent progress on the former into new results on the latter. For example, if is an abelian extension of relative degree , an odd prime, we prove the -part of the Brumer-Stark conjecture for all odd primes with belonging to a wide class of base fields. In the same setting, we study the -part and -part of Brumer-Stark with no special restriction on and are left with only two well-defined specific classes of extensions that elude proof. Extensive computations were carried out within these two classes and a complete numerical proof of the Brumer-Stark conjecture was obtained in all cases.
116.
J. M.?LandsbergEmail author L.?ManivelEmail author 《Foundations of Computational Mathematics》2004,4(4):397-422
We establish basic techniques for determining the ideals of secant varieties
of Segre varieties.We solve a conjecture of Garcia, Stillman, and Sturmfels on
the generators of the ideal of the first secant variety in the case of three factors and
solve the conjecture set-theoretically for an arbitrary number of factors. We determine
the low degree components of the ideals of secant varieties of small dimension
in a few cases. 相似文献
117.
V. F. Murzina 《Algebra and Logic》2003,42(3):181-191
A modal logic associated with the
-spaces introduced by Ershov is examined. We construct a modal calculus that is complete w.r.t. the class of all strictly linearly ordered
-frames, and the class of all strictly linearly ordered
-frames. 相似文献
118.
We present an alternative, purely semantical and relatively simple, proof of the Statman's result that both intuitionistic propositional logic and its implicational fragment are PSPACE-complete.This paper was supported by grant 401/01/0218 of the Grant Agency of the Czech Republic. %
Mathematics Subject Classification (2000): 相似文献
119.
Saharon Shelah Pauli Vä isä nen 《Transactions of the American Mathematical Society》2001,353(5):1781-1817
We prove that if is consistent then is consistent with the following statement: There is for every a model of cardinality which is -equivalent to exactly non-isomorphic models of cardinality . In order to get this result we introduce ladder systems and colourings different from the ``standard' counterparts, and prove the following purely combinatorial result: For each prime number and positive integer it is consistent with that there is a ``good' ladder system having exactly pairwise nonequivalent colourings.
120.
Gancho Tachev 《Journal of Computational Analysis and Applications》2001,3(4):361-381
A direct theorem for approximation by algebraic polynomials in two variables with different degrees in each variable in Lp-metric (1 p ) on rectangles is proved, and the dependence of the constants on various parameters is studied. 相似文献