845 resultados para How Finns learn mathematics and science
Some Characterization problems associated with the Bivariate Exponential and Geometric Distributions
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This thesis Entitled Bayesian inference in Exponential and pareto populations in the presence of outliers. The main theme of the present thesis is focussed on various estimation problems using the Bayesian appraoch, falling under the general category of accommodation procedures for analysing Pareto data containing outlier. In Chapter II. the problem of estimation of parameters in the classical Pareto distribution specified by the density function. In Chapter IV. we discuss the estimation of (1.19) when the sample contain a known number of outliers under three different data generating mechanisms, viz. the exchangeable model. Chapter V the prediction of a future observation based on a random sample that contains one contaminant. Chapter VI is devoted to the study of estimation problems concerning the exponential parameters under a k-outlier model.
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The thesis entitled Analysis of Some Stochastic Models in Inventories and Queues. This thesis is devoted to the study of some stochastic models in Inventories and Queues which are physically realizable, though complex. It contains a detailed analysis of the basic stochastic processes underlying these models. In this thesis, (s,S) inventory systems with nonidentically distributed interarrival demand times and random lead times, state dependent demands, varying ordering levels and perishable commodities with exponential life times have been studied. The queueing system of the type Ek/Ga,b/l with server vacations, service systems with single and batch services, queueing system with phase type arrival and service processes and finite capacity M/G/l queue when server going for vacation after serving a random number of customers are also analysed. The analogy between the queueing systems and inventory systems could be exploited in solving certain models. In vacation models, one important result is the stochastic decomposition property of the system size or waiting time. One can think of extending this to the transient case. In inventory theory, one can extend the present study to the case of multi-item, multi-echelon problems. The study of perishable inventory problem when the commodities have a general life time distribution would be a quite interesting problem. The analogy between the queueing systems and inventory systems could be exploited in solving certain models.
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In this thesis we investigate some problems in set theoretical topology related to the concepts of the group of homeomorphisms and order. Many problems considered are directly or indirectly related to the concept of the group of homeomorphisms of a topological space onto itself. Order theoretic methods are used extensively. Chapter-l deals with the group of homeomorphisms. This concept has been investigated by several authors for many years from different angles. It was observed that nonhomeomorphic topological spaces can have isomorphic groups of homeomorphisms. Many problems relating the topological properties of a space and the algebraic properties of its group of homeomorphisms were investigated. The group of isomorphisms of several algebraic, geometric, order theoretic and topological structures had also been investigated. A related concept of the semigroup of continuous functions of a topological space also received attention
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It is believed that every fuzzy generalization should be formulated in such a way that it contain the ordinary set theoretic notion as a special case. Therefore the definition of fuzzy topology in the line of C.L.CHANG E9] with an arbitrary complete and distributive lattice as the membership set is taken. Almost all the results proved and presented in this thesis can, in a sense, be called generalizations of corresponding results in ordinary set theory and set topology. However the tools and the methods have to be in many of the cases, new. Here an attempt is made to solve the problem of complementation in the lattice of fuzzy topologies on a set. It is proved that in general, the lattice of fuzzy topologies is not complemented. Complements of some fuzzy topologies are found out. It is observed that (L,X) is not uniquely complemented. However, a complete analysis of the problem of complementation in the lattice of fuzzy topologies is yet to be found out
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In this thesis we study the effect of rest periods in queueing systems without exhaustive service and inventory systems with rest to the server. Most of the works in the vacation models deal with exhaustive service. Recently some results have appeared for the systems without exhaustive service.
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In this thesis we attempt to make a probabilistic analysis of some physically realizable, though complex, storage and queueing models. It is essentially a mathematical study of the stochastic processes underlying these models. Our aim is to have an improved understanding of the behaviour of such models, that may widen their applicability. Different inventory systems with randon1 lead times, vacation to the server, bulk demands, varying ordering levels, etc. are considered. Also we study some finite and infinite capacity queueing systems with bulk service and vacation to the server and obtain the transient solution in certain cases. Each chapter in the thesis is provided with self introduction and some important references
Some characterization problems associated with the bivariate exponential and geometric distributions
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It is highly desirable that any multivariate distribution possessescharacteristic properties that are generalisation in some sense of the corresponding results in the univariate case. Therefore it is of interest to examine whether a multivariate distribution can admit such characterizations. In the exponential context, the question to be answered is, in what meaning— ful way can one extend the unique properties in the univariate case in a bivariate set up? Since the lack of memory property is the best studied and most useful property of the exponential law, our first endeavour in the present thesis, is to suitably extend this property and its equivalent forms so as to characterize the Gumbel's bivariate exponential distribution. Though there are many forms of bivariate exponential distributions, a matching interest has not been shown in developing corresponding discrete versions in the form of bivariate geometric distributions. Accordingly, attempt is also made to introduce the geometric version of the Gumbel distribution and examine several of its characteristic properties. A major area where exponential models are successfully applied being reliability theory, we also look into the role of these bivariate laws in that context. The present thesis is organised into five Chapters
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This thesis is a study of abstract fuzzy convexity spaces and fuzzy topology fuzzy convexity spaces No attempt seems to have been made to develop a fuzzy convexity theoryin abstract situations. The purpose of this thesis is to introduce fuzzy convexity theory in abstract situations
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Mathematicians who make significant contributions towards development of mathematical science are not getting the recognition they deserve, according to Cusat Vice Chancellor Dr. J. Letha. She was delivering the inaugural address at the International Conference on Semigroups, Algebras and Applications (ICSA 2015) organized by Dept. of Mathematics, Cochin university of Science and Technology on Thursday. Mathematics plays an important role in the development of basic science. The academic community should not delay in accepting and appreciating this, Dr. Letha added. Dr. Godfrey Louis, Dean, Faculty of Science presided over the inaugural function. Prof. P. G. Romeo, Head, Dept. of Mathematics, Prof. John C. Meakin, University of Nebraska-Lincoln, USA, Prof. A. N. Balchand, Syndicate Member, Prof. K. A. Zakkariya, Syndicate Member, Prof. A. R. Rajan, Emeritus Professor, University of Kerala and Prof. A. Vijayakumar, Dept. of Mathematics, Cusat addressed the gathering. Around 50 research papers will be presented at the Conference.Prof. K. S. S. Nambooripad, the internationally famous mathematician with enormous contributions in the field of semigroup theory, who has attained eighty years of age will be felicitated on 18th at 5.00 pm during a function presided over by Dr. K. Poulose Jacob, Pro-Vice Chancellor. Dr. Suresh Das, Executive President, KSCSTE, Dr. A. M. Mathai, Director, CMSS and President, Indian Mathematical Society, Dr. P. G. Romeo, Head, Dept. of Mathematics and Dr. B. Lakshmi, Dept. of Mathematics will speak on the occasion.
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The aim of this paper is a comprehensive presentation of some important basic and general aspects of the topic applications and modelling, with emphasis on the secondary school level. Owing to the review character of this paper, some overlap with the survey paper Blum and Niss (1989) for ICME-6 in Budapest is inevitable. The paper will consist of three parts. In part 1, I shall try to clarify some basic concepts and remind the reader of a few application and modelling examples suitable for teaching. In part 2, I shall formulate some general aims for mathematics instruction and, on that basis, summarise the most important arguments for and against applications and modelling in mathematics teaching. Finally, in part 3, I shall discuss some relevant instructional aspects resulting from the considerations in part 2.
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We present a set of techniques that can be used to represent and detect shapes in images. Our methods revolve around a particular shape representation based on the description of objects using triangulated polygons. This representation is similar to the medial axis transform and has important properties from a computational perspective. The first problem we consider is the detection of non-rigid objects in images using deformable models. We present an efficient algorithm to solve this problem in a wide range of situations, and show examples in both natural and medical images. We also consider the problem of learning an accurate non-rigid shape model for a class of objects from examples. We show how to learn good models while constraining them to the form required by the detection algorithm. Finally, we consider the problem of low-level image segmentation and grouping. We describe a stochastic grammar that generates arbitrary triangulated polygons while capturing Gestalt principles of shape regularity. This grammar is used as a prior model over random shapes in a low level algorithm that detects objects in images.
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Las recientes crisis económicas que ha vivido el mundo nos llevan a hacer una reflexión en torno a las responsabilidades que tienen los dirigentes empresariales en los cambios económicos e incluso sociales que se están viviendo. Es por tanto el momento para hacer un análisis más profundo del aporte que la administración, como ciencia, ha hecho a la sociedad. Se ha identificado que la administración permite el desarrollo y crecimiento de un individuo, al tiempo que es un medio de crecimiento y desarrollo para una comunidad, una región y una cultura, lo que se convierte en una realidad indiscutible que nos lleva a reflexionar acerca del porqué, ocurren problemas como las quiebras, ausencia de recursos, y conflictos internos en las organizaciones. En esa medida, una reflexión puede ser que los ideales que ha venido liderando la administración han sido desvirtuados y apartados de una moral y ética empresarial que permita al directivo pensar en algo más que utilidades. Podría parecer extraño decir que la empresa y la acción gerencial deben ir más allá. Podríamos iniciar con el análisis de la obsolescencia de los ideales administrativos o incluso en la ausencia de ideales en la administración. Sobre si se está teniendo en cuenta que la administración que conocemos y aprendemos sigue vigente en un mundo que ha evolucionado y cambiado, el mundo de hoy es distinto al que conocimos incluso en nuestra época de formación profesional, pues se nos enseñó a pensar linealmente, causa y efecto, todo cumple un orden y un plan predeterminado, hoy la visión de certidumbre y control del hombre sobre las decisiones son guiadas por el azar, y por más que el hombre trabaja y diseña estrategias, éstas serán transformadas de acuerdo a las emergencias. Por lo anterior, es importante entender que para avanzar y dejar la obsolescencia en los ideales que ha definido la administración, los directivos deben cambiar su visón y entender la dinámica de interrelación de sus organizaciones en un mundo en permanente caos. Debemos estudiar desde dinámicas diferentes a la de funcionalidad, y saber que es momento para que la administración tenga una nueva visión de la gestión administrativa, por lo que debemos ampliar nuestro horizonte y ver a través de la complejidad. Las decisiones que toman los directivos, las estrategias que definen y la forma de relacionarse con la competencia en mercados altamente competitivos requiere de un cambio en la administración y de un marco ético muy distinto, debe concebirse la gestión directiva y administrativa para mantener y conservar la vida del sector, de la empresa y, por ende, mantener el medio que nos rodea. Por ello se propone ejercer la administración desde la bioética.