Wyniki wyszukiwania - Biblioteka Nauki

1

Przetwornik sygnałów logiki dwuwartościowej na trójwartościową z zastosowaniem wielowejściowego wzmacniacza operacyjnego

100%

Walecki M. , Urbańczyk M.

Pomiary Automatyka Kontrola

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2011

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tom R. 57, nr 3

261-263

PL

Opisano teoretyczny model przetwornika sygnałów dwuwartościowej logiki boolowskiej na trójwartościową, dla dowolnych poziomów liczbowych wartości logicznych. Pokazano jego schemat ogólny. Zaproponowano realizację przetwornika sygnałów logicznych dwuwartościowych na trójwartościowe z zastosowaniem dwóch wielowejściowych napięciowych wzmacniaczy operacyjnych. Przedstawiono wyniki symulacji modelu układu o jednobiegunowej charakterystyce wzmocnienia.

EN

The paper describes the theoretical model of a two-state logic into a three-state logic converter for which the value of the logic levels is arbitrary. For the purpose of analysing the converter, the number of binary inputs is set to two. The general diagram of the converter is shown. The realization of a two-state-logic converter into a three-state-logic signal with use of two multiple input voltage operational amplifiers is proposed. The converter output signals obtained from simulations are presented. Numerical simulations of the converter were performed when assuming single-pole role-off characteristics of the amplifier. The goal of the analysis is to examine the converter dynamics for different periods T of the input test signals. At the given distance between the consecutive output logic levels equal to 1 V, the converter generates signals of frequency up to 1 MHz. The upper limit of this logic converter frequency range results from the operational amplifier frequency characteristics. The main advantage of the converter with a multi-input operational amplifier is its simple construction and no additional passive elements required.

2

Polowa analiza siłowników elektromagnetycznych i transformatorów

100%

Tomczuk B. , Koteras R. , Waindok A. , Zimon J.

Pomiary Automatyka Kontrola

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2011

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tom R. 57, nr 3

264-268

PL

W artykule zamieszczono wybrane wyniki badań siłowników o ruchu liniowym i nowoczesnych transformatorów. Przedstawiono zarówno modele fizyczne analizowanych obiektów, jak i ich modele matematyczne. Praca zawiera wyniki obliczeń rozkładu pola magnetycznego oraz jego parametrów całkowych dla nowoczesnego siłownika liniowego do badań zmęczeniowych, dla siłownika łożyska magnetycznego oraz transformatora z rdzeniem z blach amorficznych. Prototypy wymienionych obiektów charakteryzują się parametrami spełniającymi wymagania przyszłych użytkowników. Należy także podkreślić dobrą zgodność wyników obliczeń i pomiarów.

EN

Selected investigation results of linear actuators and modern transformers are presented in the paper. Both, physical and mathematical models of the analysed objects are shown. There are given results of calculating the magnetic field distribution and its integral parameters for three objects: a modern linear actuator for fatigue tests, a magnetic bearing actuator and amorphous core transformer. The prototypes of the mentioned objects are characterised by parameters which fulfill the future user's needs. One should underline good conformity of the calculation and measurement results. In the introduction (Section 1), the up-to-date information on linear actuators [2, 3, 4, 5, 6, 7, 8] and transformers [1, 9, 10 11] is given. In Section 2 numerical models of the analysed objects are described. In all cases the finite element method was used [12, 13, 14, 15]. The next three sections include the calculation results and measurement verification for: the linear actuator for fatigue tests (Section 3), the magnetic bearing actuator [16, 17] (Section 4) and the amorphous core transformer [18] (Section 5).

3

Communication among agents: a set theoretic approach

88%

Mousavi A. , Jabendar-Maralani P.

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tom Vol. 7, No 2

53-64

EN

This paper uses the notion of relative sets in relation to fuzzy set theory to provide a mathematical framework to analyze communication among agents. Each relative set partitions all objects into four distinct regions corresponding to four truth-values of Belnap's logic. Two orderings on relative sets are considered; one is an extension of the classical set inclusion ordering while the other is a new ordering of knowledge or information. According to these orderings, we can divide set theoretic problems into two major categories: reasoning problems and communicating problems. In the first category, an agent tries to extract a sound decision through granular reasoning. In this case, a granule represents a concept or a word. In the second category, each granule relates to an agent, and the problem is to compare agents' knowledge about concepts by their related granules, eg. a knowledge reduction problem. Then, we concentrate on the second category of problems and try to investigate this kind of problems in the context of fuzzy set theory. In this way, we could provide a basis for modeling and analyzing the relations among machines, which could communicate with each other using words and granules.

4

Mereological foundations of point-free geometry via multi-valued logic

75%

Coppola C. , Gerla G.

Logic and Logical Philosophy

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2015

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tom 24

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nr 4 Mereology and Beyond

535-553

EN

We suggest possible approaches to point-free geometry based on multi-valued logic. The idea is to assume as primitives the notion of a region together with suitable vague predicates whose meaning is geometrical in nature, e.g. ‘close’, ‘small’, ‘contained’. Accordingly, some first-order multi-valued theories are proposed. We show that, given a multi-valued model of one of these theories, by a suitable definition of point and distance we can construct a metrical space in a natural way. Taking into account that interesting metrical approaches to geometry exist, this looks to be promising for a point-free foundation of the notion of space. We hope also that this way to face point-free geometry provides a tool to illustrate the passage from a naïve and ‘qualitative’ approach to geometry to the ‘quantitative’ approach of advanced science.

5

Relative sets and rough sets

75%

Mousavi A. , Jabedar-Maralani P.

International Journal of Applied Mathematics and Computer Science

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2001

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tom 11

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nr 3

637-653

EN

In this paper, by defining a pair of classical sets as a relative set, an extension of the classical set algebra which is a counterpart of Belnap's four-valued logic is achieved. Every relative set partitions all objects into four distinct regions corresponding to four truth-values of Belnap's logic. Like truth-values of Belnap's logic, relative sets have two orderings; one is an order of inclusion and the other is an order of knowledge or information. By defining a rough set as a pair of definable sets, an integrated approach to relative sets and rough sets is obtained. With this definition, we are able to define an approximation of a rough set in an approximation space, and so we can obtain sequential approximations of a set, which is a good model of communication among agents.

6

Dekompozycja symboliczna wielowartościowych funkcji implementowanych w technologii FPGA

63%

Wiśniewski M. , Deniziak S.

Czasopismo Techniczne. Informatyka

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2011

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tom R. 108, z. 1-I

109-128

PL

W artykule przedstawiono metody dekompozycji wielowartościowych funkcji logicznych z przeznaczeniem do implementacji w układach FPGA opartych o komórki LUT. Zaprezentowana metodologia obejmuje algorytmy dekompozycji oraz kodowania funkcji symbolicznych, omówione zostały również zastosowania tej techniki do kodowania stanów oraz logicznej sieci wielowartościowej.

EN

The paper presets methods used in decomposition of multi-valued logic functions for LUT-based FPGAs. The methodology consists of algorithm of decomposition and coding technique of symbolic functions as well as using of this method for state encoding and decomposition of multi-valued logic network is presented.