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171.
A back and forth condition on interpretations for those second‐order languages without functional variables whose non‐logical vocabulary is finite and excludes functional constants is presented. It is shown that this condition is necessary and sufficient for the interpretations to be equivalent in the language. When applied to second‐order languages with an infinite non‐logical vocabulary, excluding functional constants, the back and forth condition is sufficient but not necessary. It is shown that there is a class of infinitary second‐order languages whose non‐logical vocabulary is infinite for which the back and forth condition is both necessary and sufficient. It is also shown that some applications of the back and forth construction for second‐order languages can be extended to the infinitary second‐order languages. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
172.
在二值单稳态触发器设计的基础上,提出了四值单稳态触发器的设计方案.经过PSPICE模拟,所设计的电路具有正确的逻辑功能,并能由此方法推广到基值更高的单稳态触发器的设计.与二值单稳态触发器相比,四值单稳态触发器具有更强的功能. 相似文献
173.
The Optical Implementation of High Efficiency Packed Redundant Binary Number Addition Based on Boolean Polarization-encoded L... 相似文献
174.
We consider the formulas of pure hybrid logic without occurrences of a satisfaction operator. We describe a couple of formula
derivation tactics in sequent calculus and prove the decidability of two classes of formulas. Decidable classes are obtained
by setting restrictions on nominal occurrences in the formulas.
Published in Lietuvos Matematikos Rinkinys, Vol. 44, No. 4, pp. 563–572, October–December, 2007. 相似文献
175.
Gyrgy Serny 《Mathematical Logic Quarterly》2004,50(2):211-216
Boolos's proof of incompleteness is extended straightforwardly to yield simple “diagonalization‐free” proofs of some classical limitative theorems of logic. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
176.
Norihiro Kamide 《Mathematical Logic Quarterly》2005,51(6):579-585
The logic just corresponding to (non‐commutative) involutive quantales, which was introduced by Wendy MacCaull, is reconsidered in order to obtain a cut‐free sequent calculus formulation, and the completeness theorem (with respect to the involutive quantale model ) for this logic is proved using a new admissible rule. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
177.
L. L. Maksimova 《Algebra and Logic》2006,45(1):49-66
We look at the interplay between the projective Beth property in non-classical logics and interpolation. Previously, we proved
that in positive logics as well as in superintuitionistic and modal ones, the projective Beth property PB2 follows from Craig's interpolation property and implies the restricted interpolation property IPR. Here, we show that IPR and PB2 are equivalent in positive logics, and also in extensions of the superintuitionistic logic KC and of the modal logic Grz.2.
Supported by RFBR grant No. 06-01-00358, by INTAS grant No. 04-77-7080, and by the Council for Grants (under RF President)
and State Aid of Fundamental Science Schools, project NSh-2069.2003.1.
__________
Translated from Algebra i Logika, Vol. 45, No. 1, pp. 85–113, January–February, 2006. 相似文献
178.
The classical Glivenko theorem asserts that a propositional formula admits a classical proof if and only if its double negation admits an intuitionistic proof. By a natural expansion of the BCK‐logic with negation we understand an algebraizable logic whose language is an expansion of the language of BCK‐logic with negation by a family of connectives implicitly defined by equations and compatible with BCK‐congruences. Many of the logics in the current literature are natural expansions of BCK‐logic with negation. The validity of the analogous of Glivenko theorem in these logics is equivalent to the validity of a simple one‐variable formula in the language of BCK‐logic with negation. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
179.
The algorithm and optical implementation of full parallel adder using combina-torial logic architecture have been suggested in this paper.The hybrid full parallel adder,which can perform multiple bits addition simultaneously,is implemented by utilizing VLSItechnology and acoustooptic Bragg cells.The algorithm has the advantages of high parallelismand easy optical implementation.The full parallel adder finishes n-bit addition within the du-ration T_d if the pipeline architecture is employed,whose hardware complexity is O(n~2). 相似文献
180.
Norihiro Kamide 《International Journal of Theoretical Physics》2005,44(4):399-428
Completeness and cut-elimination theorems are proved for some Gentzen-type sequent calculi which are closely related to non-commutative involutive quantales. 相似文献