955 resultados para Mathematical logic
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RelAPS is an interactive system assisting in proving relation-algebraic theorems. The aim of the system is to provide an environment where a user can perform a relation-algebraic proof similar to doing it using pencil and paper. The previous version of RelAPS accepts only Horn-formulas. To extend the system to first order logic, we have defined and implemented a new language based on theory of allegories as well as a new calculus. The language has two different kinds of terms; object terms and relational terms, where object terms are built from object constant symbols and object variables, and relational terms from typed relational constant symbols, typed relational variables, typed operation symbols and the regular operations available in any allegory. The calculus is a mixture of natural deduction and the sequent calculus. It is formulated in a sequent style but with exactly one formula on the right-hand side. We have shown soundness and completeness of this new logic which verifies that the underlying proof system of RelAPS is working correctly.
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Dynamic logic is an extension of modal logic originally intended for reasoning about computer programs. The method of proving correctness of properties of a computer program using the well-known Hoare Logic can be implemented by utilizing the robustness of dynamic logic. For a very broad range of languages and applications in program veri cation, a theorem prover named KIV (Karlsruhe Interactive Veri er) Theorem Prover has already been developed. But a high degree of automation and its complexity make it di cult to use it for educational purposes. My research work is motivated towards the design and implementation of a similar interactive theorem prover with educational use as its main design criteria. As the key purpose of this system is to serve as an educational tool, it is a self-explanatory system that explains every step of creating a derivation, i.e., proving a theorem. This deductive system is implemented in the platform-independent programming language Java. In addition, a very popular combination of a lexical analyzer generator, JFlex, and the parser generator BYacc/J for parsing formulas and programs has been used.
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This research study explored how undergraduate mathematics students perceive themselves as capable mathematics learners and whether gender differences exist in the undergraduates students' perceptions. The research was framed by three approaches of understanding identity: self-efficacy, environment, and four faces of learner's identity. A mixed methods approach to the study was used where data were collected from interviews and an online questionnaire. Data analysis revealed that undergraduate mathematics students' perceptions of their mathematical identity as capable mathematics learners are influenced by their perceptions of their experiences such as: (a) perceptions of having previous knowledge of the course, (b) being able teach others and others understand it, (c) being recognized by their professors, (d) contributing and fitting in, (e) having opportunities to interact with their peers, and (f) being able to fit in with their image of a capable mathematics learner.
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UANL
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This Paper Intends to Develop a Coherent Methodological Framework Concerned with the Appraisal of Scientific Theories in Economics, and Which Is Based on a Postulated Aim of Science. We First Define the Scope of a Methodological Inquiry (Precise Definition of What Is Meant by the Logic of Appraisal of Scientific Theories) and Review the Work of Popper and Lakatos in the Philosophy of Science. We Then Use Their Results to Develop a Rational Structure of Scientific Activity. We Identify and Analyse Both a Micro and Macro Framework for the Process of Appraisal and Single Out the Importance of So-Called 'Fundamental Assumptions' in Creating Externalities in the Appraisal Process Which Forces Us to Adop a Multi-Level Analysis. Special Attention Is Given to the Role and Significance of the Abstraction Process and the Use of Assumptions in General. the Proposed Structure of Scientific Activity Is Illustrated with Examples From Economics.
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Partant des travaux séminaux de Boole, Frege et Russell, le mémoire cherche à clarifier l‟enjeu du pluralisme logique à l‟ère de la prolifération des logiques non-classiques et des développements en informatique théorique et en théorie des preuves. Deux chapitres plus « historiques » sont à l‟ordre du jour : (1) le premier chapitre articule l‟absolutisme de Frege et Russell en prenant soin de montrer comment il exclut la possibilité d‟envisager des structures et des logiques alternatives; (2) le quatrième chapitre expose le chemin qui mena Carnap à l‟adoption de la méthode syntaxique et du principe de tolérance, pour ensuite dégager l‟instrumentalisme carnapien en philosophie de la Logique et des mathématiques. Passant par l‟analyse d‟une interprétation intuitive de la logique linéaire, le deuxième chapitre se tourne ensuite vers l‟établissement d‟une forme logico-mathématique de pluralisme logique à l‟aide de la théorie des relations d‟ordre et la théorie des catégories. Le troisième chapitre délimite le terrain de jeu des positions entourant le débat entre monisme et pluralisme puis offre un argument contre la thèse qui veut que le conflit entre logiques rivales soit apparent, le tout grâce à l‟utilisation du point de vue des logiques sous-structurelles. Enfin, le cinquième chapitre démontre que chacune des trois grandes approches au concept de conséquence logique (modèle-théorétique, preuve-théorétique et dialogique) forme un cadre suffisamment général pour établir un pluralisme. Bref, le mémoire est une défense du pluralisme logique.
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Thèse diffusée initialement dans le cadre d'un projet pilote des Presses de l'Université de Montréal/Centre d'édition numérique UdeM (1997-2008) avec l'autorisation de l'auteur.
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Cette thèse propose une étude des raisons théoriques et empiriques impliquées dans l’élaboration d’une nouvelle astronomie par Johannes Kepler (1571-1630) tel qu’exposé dans son ouvrage Astronomia nova (1619). Cette thèse se déroule en deux temps : la première partie touche de près aux textes mêmes de Kepler, tandis que la seconde partie utilise la notion d’abduction pour interpréter logiquement ce processus de découverte et de justification. La première partie débute avec une analyse du projet de Kepler et de ses fondements philosophiques, métaphysiques et théologiques tels qu’exposés dans son premier ouvrage, le Mysterium cosmographicum. Ensuite, une étude des propos explicites de Kepler quant à la nature et au statut des hypothèses astronomiques est proposée via une étude de son traité intitulé Apologia pro Tychone contra Ursum. Une étude attentive des sources philosophiques, mathématiques et scientifiques ayant influencé Kepler pour sa nouvelle astronomie est ensuite proposée avant l’analyse détaillée des arguments scientifiques et des différentes étapes démonstratives qui sont présentés dans l’Astronomia nova. La deuxième partie vise à éclairer le débat sur l’abduction en se penchant d’abord sur trois approches traditionnelles (Platon, Aristote et Épicure) quant à la connaissance scientifique des phénomènes célestes permettant d’obtenir un discours vraisemblable ou une multiplicité d’explications concordantes avec les phénomènes. Enfin, quatre interprétations contemporaines et abductives du processus de découverte suivi par Kepler dans l’Astronomia nova sont présentées, reformulées et critiquées afin de proposer une nouvelle interprétation abductive laissant une plus grande place au projet même de construire une astronomie nouvelle fondée sur les causes. Cela nous donne des outils pour mieux saisir le sens et la portée de ce qui peut être désigné comme étant la « révolution képlérienne », soit le passage d’un système géocentrique à un système non pas simplement héliocentrique mais héliodynamique, ayant permis aux astronomes de s’affranchir du paradigme des orbites circulaires.
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This paper introduces and examines the logicist construction of Peano Arithmetic that can be performed into Leśniewski’s logical calculus of names called Ontology. Against neo-Fregeans, it is argued that a logicist program cannot be based on implicit definitions of the mathematical concepts. Using only explicit definitions, the construction to be presented here constitutes a real reduction of arithmetic to Leśniewski’s logic with the addition of an axiom of infinity. I argue however that such a program is not reductionist, for it only provides what I will call a picture of arithmetic, that is to say a specific interpretation of arithmetic in which purely logical entities play the role of natural numbers. The reduction does not show that arithmetic is simply a part of logic. The process is not of ontological significance, for numbers are not shown to be logical entities. This neo-logicist program nevertheless shows the existence of a purely analytical route to the knowledge of arithmetical laws.
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The current study is aimed at the development of a theoretical simulation tool based on Discrete Element Method (DEM) to 'interpret granular dynamics of solid bed in the cross section of the horizontal rotating cylinder at the microscopic level and subsequently apply this model to establish the transition behaviour, mixing and segregation.The simulation of the granular motion developed in this work is based on solving Newton's equation of motion for each particle in the granular bed subjected to the collisional forces, external forces and boundary forces. At every instant of time, the forces are tracked and the positions velocities and accelarations of each partcle is The software code for this simulation is written in VISUAL FORTRAN 90 After checking the validity of the code with special tests, it is used to investigate the transition behaviour of granular solids motion in the cross section of a rotating cylinder for various rotational speeds and fill fraction.This work is hence directed towards a theoretical investigation based on Discrete Element Method (DEM) of the motion of granular solids in the radial direction of the horizontal cylinder to elucidate the relationship between the operating parameters of the rotating cylinder geometry and physical properties ofthe granular solid.The operating parameters of the rotating cylinder include the various rotational velocities of the cylinder and volumetric fill. The physical properties of the granular solids include particle sizes, densities, stiffness coefficients, and coefficient of friction Further the work highlights the fundamental basis for the important phenomena of the system namely; (i) the different modes of solids motion observed in a transverse crosssection of the rotating cylinder for various rotational speeds, (ii) the radial mixing of the granular solid in terms of active layer depth (iii) rate coefficient of mixing as well as the transition behaviour in terms of the bed turnover time and rotational speed and (iv) the segregation mechanisms resulting from differences in the size and density of particles.The transition behaviour involving its six different modes of motion of the granular solid bed is quantified in terms of Froude number and the results obtained are validated with experimental and theoretical results reported in the literature The transition from slumping to rolling mode is quantified using the bed turnover time and a linear relationship is established between the bed turn over time and the inverse of the rotational speed of the cylinder as predicted by Davidson et al. [2000]. The effect of the rotational speed, fill fraction and coefficient of friction on the dynamic angle of repose are presented and discussed. The variation of active layer depth with respect to fill fraction and rotational speed have been investigated. The results obtained through simulation are compared with the experimental results reported by Van Puyvelde et. at. [2000] and Ding et at. [2002].The theoretical model has been further extended, to study the rmxmg and segregation in the transverse direction for different particle sizes and their size ratios. The effect of fill fraction and rotational speed on the transverse mixing behaviour is presented in the form of a mixing index and mixing kinetics curve. The segregation pattern obtained by the simulation of the granular solid bed with respect to the rotational speed of the cylinder is presented both in graphical and numerical forms. The segregation behaviour of the granular solid bed with respect to particle size, density and volume fraction of particle size has been investigated. Several important macro parameters characterising segregation such as mixing index, percolation index and segregation index have been derived from the simulation tool based on first principles developed in this work.
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A sensitive method based on the principle of photothermal phenomena to realize optical logic gates is presented. A dual beam thermal lens method using low power cw lasers in a dye-doped polymer can be very effectively used as an alternate technique to perform the logical function such as NAND, AND and OR.
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The present work deals with the A study of morphological opertors with applications. Morphology is now a.necessary tool for engineers involved with imaging applications. Morphological operations have been viewed as filters the properties of which have been well studied (Heijmans, 1994). Another well-known class of non-linear filters is the class of rank order filters (Pitas and Venetsanopoulos, 1990). Soft morphological filters are a combination of morphological and weighted rank order filters (Koskinen, et al., 1991, Kuosmanen and Astola, 1995). They have been introduced to improve the behaviour of traditional morphological filters in noisy environments. The idea was to slightly relax the typical morphological definitions in such a way that a degree of robustness is achieved, while most of the desirable properties of typical morphological operations are maintained. Soft morphological filters are less sensitive to additive noise and to small variations in object shape than typical morphological filters. They can remove positive and negative impulse noise, preserving at the same time small details in images. Currently, Mathematical Morphology allows processing images to enhance fuzzy areas, segment objects, detect edges and analyze structures. The techniques developed for binary images are a major step forward in the application of this theory to gray level images. One of these techniques is based on fuzzy logic and on the theory of fuzzy sets.Fuzzy sets have proved to be strongly advantageous when representing in accuracies, not only regarding the spatial localization of objects in an image but also the membership of a certain pixel to a given class. Such inaccuracies are inherent to real images either because of the presence of indefinite limits between the structures or objects to be segmented within the image due to noisy acquisitions or directly because they are inherent to the image formation methods.
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The present study is intended to provide a new scientific approach to the solution of the worlds cost engineering problems encountered in the chemical industries in our nation. The problem is that of cost estimation of equipments especially of pressure vessels when setting up chemical industries .The present study attempts to develop a model for such cost estimation. This in turn is hoped would go a long way to solve this and related problems in forecasting the cost of setting up chemical plants.
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Reversibility plays a fundamental role when logic gates such as AND, OR, and XOR are not reversible. computations with minimal energy dissipation are considered. Hence, these gates dissipate heat and may reduce the life of In recent years, reversible logic has emerged as one of the most the circuit. So, reversible logic is in demand in power aware important approaches for power optimization with its circuits. application in low power CMOS, quantum computing and A reversible conventional BCD adder was proposed in using conventional reversible gates.