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91.
In the current paper we consider theories with vocabulary containing a number of binary and unary relation symbols. Binary relation symbols represent labeled edges of a graph and unary relations represent unique annotations of the graph’s nodes. Such theories, which we call annotation theories, can be used in many applications, including the formalization of argumentation, approximate reasoning, semantics of logic programs, graph coloring, etc. We address a number of problems related to annotation theories over finite models, including satisfiability, querying problem, specification of preferred models and model checking problem. We show that most of considered problems are NPTime- or co-NPTime-complete. In order to reduce the complexity for particular theories, we use second-order quantifier elimination. To our best knowledge none of existing methods works in the case of annotation theories. We then provide a new second-order quantifier elimination method for stratified theories, which is successful in the considered cases. The new result subsumes many other results, including those of [2, 28, 21]. 相似文献
92.
Journal of Happiness Studies - The article concentrates on regulatory focus (promotion and prevention) as a factor involved in the relationships between materialism and well-being alongside two... 相似文献
93.
94.
95.
Jarosław Achinger 《Studia Logica》1986,45(3):281-292
In the paper [2] the following theorem is shown: Theorem (Th. 3,5, [2]), If α=0 or δ=∞ or α?δ, then a closure space X is an absolute extensor for the category of 〈α, δ〉 -closure spaces iff a contraction of X is the closure space of all 〈α, δ〉-filters in an 〈α, δ〉-semidistributive lattice. In the case when α=ω and δ=∞, this theorem becomes Scott's theorem: Theorem ([7]). A topological space X is an absolute extensor for the category of all topological spaces iff a contraction of X is a topological space of “Scott's open sets” in a continuous lattice. On the other hand, when α=0 and δ=ω, this theorem becomes Jankowski's theorem: Theorem ([4]). A closure space X is an absolute extensor for the category of all closure spaces satisfying the compactness theorem iff a contraction of X is a closure space of all filters in a complete Heyting lattice. But for separate cases of α and δ, the Theorem 3.5 from [2] is proved using essentialy different methods. In this paper it is shown that this theorem can be proved using, for retraction, one uniform formula. Namely it is proved that if α= 0 or δ= ∞ or α ? δ and \(F_{\alpha ,\delta } \left( L \right) \subseteq B_{\alpha ,\delta }^\mathfrak{n} \) and if L is an 〈α, δ〉-semidistributive lattice, then the function $$r:{\text{ }}B_{\alpha ,\delta }^\mathfrak{n} \to F_{\alpha ,\delta } \left( L \right)$$ such that for x ε ? ( \(\mathfrak{n}\) ): (*) $$r\left( x \right) = inf_L \left\{ {l \in L|\left( {\forall A \subseteq L} \right)x \in C\left( A \right) \Rightarrow l \in C\left( A \right)} \right\}$$ defines retraction, where C is a proper closure operator for \(B_{\alpha ,\delta }^\mathfrak{n} \) . It is also proved that the formula (*) defines retraction for all 〈α, δ〉, whenever L is an 〈α, δ〉 -pseudodistributive lattice. Moreover it is proved that when α=ω and δ=∞, the formula (*) defines identical retraction to the formula given in [7], and when α = 0 and δ=ω, the formula (*) defines identical retraction to the formula given in [4]. 相似文献
96.
Małgorzata Porębska 《Studia Logica》1986,45(1):35-38
Important positive as well as negative results on interpolation property in fragments of the intuitionistic propositional logic (INT) were obtained by J. I. Zucker in [6]. He proved that the interpolation theorem holds in purely implicational fragment of INT. He also gave an example of a fragment of INT for which interpolation fails. This fragment is determined by the constant falsum (), well known connectives: implication () and conjunction (), and by a ternary connective defined as follows: (p, q, r)=
df
(pq)(pr).Extending this result of J. I. Zucker, G. R. Renardel de Lavalette proved in [5] that there are continuously many fragments of INT without the interpolation property.This paper is meant to continue the research mentioned above. To be more precise, its aim is to answer questions concerning interpolation and amalgamation properties in varieties of equivalential algebras, particularly in the variety determined by the purely equivalential fragment of INT. 相似文献
97.
Bronisław Tembrowski 《Studia Logica》1986,45(2):167-179
The first part of the paper deals with some subclasses of B-algebras and their applications to the semantics of SCI
B
, the Boolean strengthening of the sentential calculus with identity (SCI). In the second part a generalization of the McKinsey-Tarski construction of well-connected topological Boolean, algebras to the class of B-algebras is given. 相似文献
98.
Władysław Krajewski 《国际科学哲学研究》1997,11(2):185-190
Three main concepts of model in science are distinguished: (1) semantical model of a theory; (2) real model of another real thing; (3) mathematical model of a real thing. The last concept is the most important for the empirical sciences. The mathematical model is not identical with a theory: it is an ideal object which is directly described by the theory. We have here an intermediate level between reality and theory. 相似文献
99.
Studies in East European Thought - 相似文献
100.
The Agam program was designed to foster visual thinking in young children by developing their visual language. This curriculum was implemented in five nursery classes for 2 consecutive school years. Children in these classes were compared with children in classes where the program was not administered. It was hypothesized that the generative nature of the visual language developed in the experimental children would allow the children to extend the language learned to new situations and help them to solve problems in which no prior training was given. Test results confirmed this hypothesis: The effects of training in the Agam program transferred to cognitive domains in which no training was given. Specifically, the findings indicated positive effects on general intelligence and school readiness of children about to enter first grade, with especially pronounced effects in the areas of arithmetic and writing readiness. Other findings revealed an increased visual learning ability in new tasks that developed in the experimental children. Training effects did not transfer to mental rotation and to memory for realistic designs. The program was found to be equally effective for lower-class as for middle-class children. The effect of the program was greater for children who participated in the program for 2 years as compared with those who joined in the second year, indicating a cumulative effect of the program. This latter finding can also be used to refute an alternative explanation of the obtained experimental effects offered by a motivational theory. The findings on cognitive transfer, taken together with previously reported on concept learning and visual skills, point to the educational potential of the approach advocated by the Agam program, that is, systematic long-term instruction in the domain of visual cognition in early childhood. 相似文献