In Chajda's paper (2014), to an arbitrary BCI-algebra the author assigned an ordered structure with one binary operation which possesses certain antitone mappings. In the present paper, we show that a similar construction can be done also for pseudo-BCI-algebras, but the resulting structure should have two binary operations and a set of couples of antitone mappings which are in a certain sense mutually inverse. The motivation for this approach is the well-known fact that every commutative BCK-algebra is in fact a join-semilattice and we try to obtain a similar result also for the non-commutative case and for pseudo-BCI-algebras which generalize BCK-algebras, see e.g. Imai and Iséki (1966) and Iséki (1966).
The paper outlines an epistemic logic based on the proof theory of substructural logics. The logic is a formal model of belief that i) is based on true assumptions (BTA belief) and ii) does not suffer from the usual omniscience properties., Článek nastiňuje epistemickou logiku založenou na důkazové teorii substrukturální logiky. Logika je formálním modelem víry, že i) je založena na pravdivých předpokladech (víra BTA) a ii) netrpí obvyklými vševědoucími vlastnostmi., and Igor Sedlár
This paper deals with a certain class of unbounded optimization problems. The optimization problems taken into account depend on a parameter. Firstly, there are established conditions which permit to guarantee the continuity with respect to the parameter of the minimum of the optimization problems under consideration, and the upper semicontinuity of the multifunction which applies each parameter into its set of minimizers. Besides, with the additional condition of uniqueness of the minimizer, its continuity is given. Some examples of nonconvex optimization problems that satisfy the conditions of the article are supplied. Secondly, the theory developed is applied to discounted Markov decision processes with unbounded cost functions and with possibly noncompact actions sets in order to obtain continuous optimal policies. This part of the paper is illustrated with two examples of the controlled Lindley's random walk. One of these examples has nonconstant action sets.
Let $G=(V, E)$ be a simple graph. A subset $S\subseteq V$ is a dominating set of $G$, if for any vertex $u\in V-S$, there exists a vertex $v\in S$ such that $uv\in E$. The domination number, denoted by $\gamma (G)$, is the minimum cardinality of a dominating set. In this paper we will prove that if $G$ is a 5-regular graph, then $\gamma (G)\le {5\over 14}n$.
The basis number of a graph $G$ is defined by Schmeichel to be the least integer $h$ such that $G$ has an $h$-fold basis for its cycle space. MacLane showed that a graph is planar if and only if its basis number is $\le 2$. Schmeichel proved that the basis number of the complete graph $K_n$ is at most $3$. We generalize the result of Schmeichel by showing that the basis number of the $d$-th power of $K_n$ is at most $2d+1$.
The paper concerns mining data lacking the uniform structure. The
data are collected from a riumber of objects during repeated measurenients, all of which are tagged by a corresponding time. No attribute-valued machine learning algorithm can be applied directly on such data since the number of measurements is not fixed but it varies. The available data háve to be transformed and preprocessed in such a way that a uniform type of Information is obtained about all the considered objects. This can be achieved, e.g., by aggregation. But this process can introduce anachronistic variables, i.e., variables containing Information which cannot be available at the moment when a prediction is needed. The paper suggests and tests a method how to preprocess the considered type of data without falling into a trap of introducing anachronistic attributes. The method is illustrated on a čase study baaed on STULONG data.
This paper deals with the problem of semantic analysis of contexts involving so-called anaphoric chain. The notion of anaphoric chain is explained by way of an example. Afterwards, a semantic analysis of sentences containing anaphora established in Transparent Intensional Logic (TIL) is examined. It is demonstrated that it is not adequate for texts including anaphoric chains. An alternative method using TIL that is capable to deal with all kinds of anaphora is proposed. Anyway, one may raise doubts as to whether both approaches are really analyses of anaphorically used expressions., Článek se zabývá problematikou sémantické analýzy kontextů zahrnujících tzv. Anaforický řetězec . Pojem anaforický řetězec je vysvětlen na příkladu. Následně je zkoumána sémantická analýza vět obsahujících anaforu vytvořených v transparentní intenzivní logice (TIL). Je prokázáno, že není vhodný pro texty obsahující anaforické řetězce. Navrhuje se alternativní metoda používající TIL, která je schopna se vypořádat se všemi druhy anafor. V každém případě lze pochybovat, zda jsou oba přístupy skutečně analýzou anaforicky používaných výrazů., and Miloš Kosterec