Wyniki wyszukiwania - Biblioteka Nauki

1

From the segmentation to the complete reading of a mathematical document

100%

Toumit J. Y. , Emptoz H.

Machine Graphics and Vision

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1998

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tom Vol. 7, No. 1/2

485-504

EN

Automatic reading of scolar manuals is an important problem for the editors; we are presently working in this context on the conversion of mathematical manuals into electronic documents. No research on the entire mathematical document seem to have been achieved until now, there has been only stidies on the formulas themselves. We therefore present the problem of reading such documents. Those documents contain two types of information of different natures: the next and the mathematical objects. To perform a better treatment on the text itself, we are leaded to separate those two types of information; in this article, we pay a paricular attention to this treatment which can be considered as a multi-language segmentation problem. Classical methods do not provide satisfactory results and we needed to introduce a new segmentation approach; it fills the document's surface using "propabation" methods around particularity specyfic points of the text or of the mathematical objects. We also analysed the constraints relative to the documents we have to deal with; in this context, we need to use the gray-level image without binarizing it. A method for segmenting words and characters using this gray-level image is presented and we then introduce tetrarization which leads to more reliable images than binarized images.

2

Improvements in SAT-based Reachability Analysis for Timed Automata

100%

Zbrzezny A.

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2004

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tom Vol. 60, nr 1-4

417--434

EN

The paper deals with the problem of checking reachability for timed automata. In order to check reachability of a state satisfying some property, first the transition relation of a timed automaton is unfolded iteratively to some depth and encoded as a propositional formula. Next, the property is translated to a propositional formula and satisfiability of the conjunction of the two defined above formulas is checked. The unfolding of the transition relation can be terminated when either a state satisfying the property has been found or all the states of the timed automaton have been searched. In this paper we propose some improvements of the encoding of the transition relation for timed automata. The improvements are partially based on a new discretization scheme. The efficiency of the improved encoding is strongly supported by the experimental results. We also introduce a method for checking unreachability.

3

SAT-based Bounded Model Checking for Weighted Deontic Interpreted Systems

88%

Woźna-Szcześniak B.

Fundamenta Informaticae

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2016

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tom Vol. 143, nr 1/2

173--205

EN

We present WECTL*KD, a weighted branching time temporal logic to specify knowledge, and correct functioning behaviour in multi-agent systems (MAS).We interpret the formulae of the logic over models generated by weighted deontic interpreted systems (WDIS). Furthermore, we investigate a SAT-based bounded model checking (BMC) technique for WDIS and for WECTL*KD.

4

Virtual cubarithms : innovative assistive technology for teaching the blind and visually impaired students traditional columnar layout operations

88%

Mikułowski D. , Terlikowski G. , Brzostek-Pawłowska J.

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tom Vol. 1-2(20)

17--25

EN

Blind students face significant barriers in their mathematical education. Despite currently available computer technologies they are not able to perform some simple operations, for instance, traditional columnar layout calculations, using a sheet of paper like their sighted peers. They have to use a traditional tool, namely, a cubarithm slate. In this paper a solution has been proposed to help blind students to learn and perform basic mathematical calculations with the help of a mobile device with touch screen. It is a Virtual Cubarithm application developed as a part of a larger research project called PlatMat. PlatMat is a special mobile platform supporting sighted teachers and their visually impaired students mathematical and physical education. Virtual cubarithm is a tool for learning traditional columnar layout calculations by visually impaired students. It is meant to replace traditional cubarithm slates, which are still in use.

5

Twelve Years of QBF Evaluations : QSAT Is PSPACE-Hard and It Shows

88%

Marin P. , Pulina L. , Giunchiglia E. , Narizzano M. , Tacchella A.

Fundamenta Informaticae

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2016

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tom Vol. 149, nr 1/2

133--158

EN

Twelve years have elapsed since the first Quantified Boolean Formulas (QBFs) evaluation was held as an event linked to SAT conferences. During this period, researchers have striven to propose new algorithms and tools to solve challenging formulas, with evaluations periodically trying to assess the current state of the art. In this paper, we present an experimental account of solvers and formulas with the aim to understand the progress in the QBF arena across these years. Unlike typical evaluations, the analysis is not confined to the snapshot of submitted solvers and formulas, but rather we consider several tools that were proposed over the last decade, and we run them on different formulas from previous QBF evaluations. The main contributions of our analysis, which are also the messages we would like to pass along to the research community, are: (i) many formulas that turned out to be difficult to solve in past evaluations, remain still challenging after twelve years, (ii) there is no single solver which can significantly outperform all the others, unless specific categories of formulas are considered, and (iii) effectiveness of preprocessing depends both on the coupled solver and the structure of the formula.

6

More on Square-free Words Obtained from Prefixes by Permutations

88%

Ochem P.

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tom Vol. 132, nr 1

109--112

EN

An infinite square-free word w over the alphabet Σ3 = {0, 1, 2} is said to have a k-stem σ if |σ| = k and w = σw1w2· · · where for each i, there exists a permutation πi of Σ3 which extended to a morphism gives wi= πi (σ). Harju proved that there exists an infinite k-stem word for k = 1, 2, 3, 9 and 13 ≤ k ≤ 19, but not for 4 ≤ k ≤ 8 and 10 ≤ k ≤ 12. He asked whether k-stem words exist for each k ≥ 20. We give a positive answer to this question. Currie has found another construction that answers Harju’s question.

7

A Function Elimination Method for Checking Satisfiability of Arithmetical Logics

88%

Castiglioni V. , Lanotte R. , Tini S.

Fundamenta Informaticae

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2016

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tom Vol. 143, nr 1/2

51--71

EN

We study function elimination for Arithmetical Logics. We propose a method allowing substitution of functions occurring in a given formula with functions with less arity. We prove the correctness of the method and we use it to show the decidability of the satisfiability problem for two classes of formulas allowing linear and polynomial terms.

8

ACBC-Adequate Association and Decision Rules Versus Key Generators and Rough Sets Approximations

88%

Kryszkiewicz M.

Fundamenta Informaticae

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2016

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tom Vol. 148, nr 1/2

65--85

EN

In this paper, we propose an ACBC-evaluation formula, which delivers a flexible way of formulating different kinds of criteria for association and decision rules. We prove that rules with minimal antecedents that fulfill ACBC-evaluation formulae are key generators, which are patterns of a special type. We also show that a number of types of rough set approximations of decision classes can be expressed based on ACBC-evaluation formulae. We prove that decision rules preserving respective approximations of decision classes are rules that satisfy an ACBC-evaluation formula and that antecedents of such optimal decision rules are key generators, too. A number of properties related to particular measures of association rules and key generators are derived.

9

Rough Net Structures : Example of Information System

75%

Czaja L.

Fundamenta Informaticae

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2013

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tom Vol. 127, nr 1-4

81--97

EN

Information system of net structures based on their calculus (a distributive lattice) is introduced and, in this context, basic notions of rough set theory are re-formulated and exemplified.

10

Proving Propositional Tautologies in a Natural Dialogue

75%

Yaskorska O. , Budzynska K. , Kacprzak M.

Fundamenta Informaticae

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2013

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tom Vol. 128, nr 1-2

239--253

EN

The paper proposes a dialogue system LND which brings together and unifies two traditions in studying dialogue as a game: the dialogical logic introduced by Lorenzen; and persuasion dialogue games as specified by Prakken. The first approach allows the representation of formal dialogues in which the validity of argument is the topic discussed. The second tradition has focused on natural dialogues examining, e.g., informal fallacies typical in real-life communication. Our goal is to unite these two approaches in order to allow communicating agents to benefit from the advantages of both, i.e., to equip them with the ability not only to persuade each other about facts, but also to prove that a formula used in an argument is a classical propositional tautology. To this end, we propose a new description of the dialogical logic which meets the requirements of Prakken's generic specification for natural dialogues, and we introduce rules allowing to embed a formal dialogue in a natural one. We also show the correspondence result between the original and the new version of the dialogical logic, i.e., we show that a winning strategy for a proponent in the original version of the dialogical logic means a winning strategy for a proponent in the new version, and conversely.

11

Analiza formuł opisujących spadki ciśnienia powietrza przepływającego przez złoże bezprzeponowego gruntowego wymiennika ciepła

63%

Romański L.

Problemy Inżynierii Rolniczej

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2001

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tom R. 9, nr 2

73-78

PL

Dokonano analizy formuł matematycznych umożliwiających wyznaczenie spadków ciśnienia powietrza przepływającego przez złoże gruntowego wymiennika ciepła. Obliczone wartości porównano z wartościami pomiarowymi uzyskanymi w modelu złoża wymiennika wykonanego z kul ceramicznych o średnicy 25 mm. Stwierdzono dużą niezgodność pomiędzy wartościami formuł literaturowych i pomiarowymi.

EN

Existing mathematical formulas, that enable to determine the pressure drops of air flowing through the rock bed of ground heat exchanger, were analysed. Calculated values were compared to measurement results obtained on a model heat exchanger with a bed consisted of 25 mm diameter ceramic balls. The comparison showed considerable disagreement between theoretical values from formulas and really measuder values.