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Full-Text Articles in Mathematics

Studies On Finite Linear Cellular Automata., Palash Sarkar Dr. Feb 2000

Studies On Finite Linear Cellular Automata., Palash Sarkar Dr.

Doctoral Theses

Cellular Automata were originally proposed by John von Neumann as formal models of self reproducing organisms. The structure studied was mostly an ane and two dimensional infinite grida, though higher dimensions were also considered. Computation universality and other computation theoretic questions were considered important. See Burks [24] for a collection of essays on important problems on cellular automata during this period. Later physicists and biologists began to study cellular automsta for the purpose of modelling in their respective domains. In the present era, cellalar automata is being atudied from many widely different angles, and the relationship of these structurea to …


Uncertainity Principles On Some Lie Groups., Swagato Kumar Ray Dr. Feb 2000

Uncertainity Principles On Some Lie Groups., Swagato Kumar Ray Dr.

Doctoral Theses

The uncertainty principles of Harmonic Analysis say that: a nonzero func- tion and its Fourier transform cannot both be sharply concen- trated. After the initial work on this phenomenon in 1920s, the last two decades witnessed a spurt of activity in this direction (we refer the reader to a very readable survey [FS]). One may notice two broad phases in this activity, the first concentrating on R where the notion of concentration is given different formulations to see whether the phenomenon still holds. In the later phase R is replaced by other commutative or noncommutative groups, or more generally by …


Generalised Bootstrap Techniques., Singdhansu Bhusan Chatterjee Dr. Feb 2000

Generalised Bootstrap Techniques., Singdhansu Bhusan Chatterjee Dr.

Doctoral Theses

A typical problem in statistics is as follows: there is some observable data Xn = (X1,..., Xn), and a parameter of interest θ which is related in such a way to the distribution of Xn that meaningful conclusions about θ can be drawn based on Xn. Sometimes data Xn is observed keeping the objective parameter θ in mind, at other times the parameter appears while trying to model the observed data.Once the data is observed and the parameter fixed, the questions that have to be addressed are as follows:(I) How to estimate θ from the data Xn?(II) Given an estimator …


On Quantitative Evaluation Of 3-D Histo-Pathological Images From Confocal Laser Scanning Microscope., P. S. Umesh Adiga Dr. Feb 2000

On Quantitative Evaluation Of 3-D Histo-Pathological Images From Confocal Laser Scanning Microscope., P. S. Umesh Adiga Dr.

Doctoral Theses

Automation of image analysis in the bio-medical ficld is one of the important achievements of applied image processing research. The rapid development in the electronic instrumentation during 1960s and 70s made it possible to automate the routine process of diagnosis and prognosis of many discases. Development of high resolution imaging instruments such as X-ray CT, MRI, etc., for macro imaging and electron microscope, confocal microscope, etc., for micro imaging has given a tremendous boost to the advancement of medical field. Advancement in the field of computing has made it possible to reconstruct the pictures of internal organs of the body …


Perturbed Laplacian Matrix And The Structure Of A Graph., Sukanta Pati Dr. Jan 2000

Perturbed Laplacian Matrix And The Structure Of A Graph., Sukanta Pati Dr.

Doctoral Theses

Laplacian matrices Let G be a connected simple graph with vertex set V = {1,2,.,n), edge set E and let each edge be associated with a positive number, the weight of the edge. The above graph is called a weighted graph. An unweighted graph is just a weighted graph with each of the edges bearing weight 1. All the graphs considered are weighted and simple, unless specified otherwise; all the matrices considered are real. The adjacency matrix A(G) related to this graph is defined as A(G) = (aij), whereaij, if (i, j] € E and the weight of the edge …


On Measuring The Cost Of Children:The Case Of Rural Maharashtra., Manisha Chakrabarty Dr. Nov 1999

On Measuring The Cost Of Children:The Case Of Rural Maharashtra., Manisha Chakrabarty Dr.

Doctoral Theses

In this dissertation we have attempted to measure the cost of children, which plays a crucial role in matters relating to welfare and public policy like child benefits and compensation policies of the government. The cost is measured based on the single equation as well as the systems approach using the 38th round National Sample Survey (NSS) data on household consumer expenditure for rural Maharashtra (relating to the period of January to December, 1983).The first chapter provides a brief account of the basic literature on empirical demand analysis which is relevant for welfare comparison between households. To be specific in …


Essays In Mechanism Design., Suresh Mutuswami Dr. Jul 1999

Essays In Mechanism Design., Suresh Mutuswami Dr.

Doctoral Theses

The theory of implementation or mechanism design had its origins in the debates in the 1930s between Hayek, Lange and Lerner on the informational efficiency of the market economy. However, it was the work of Hurwicz in the 1950s and the 1960s which formalised the insights of Hayek, Lange and Lerner and paved the way for the body of work that followed his pioneering effort.In addition to the considerable theoretical literature on mechanism de- sign'. there also exists a body of literature which uses the mechanism design approach to address specific problems. Some examples of work in this vein include …


International Joint Ventures And Technology Transfer In Developing Economies., Arijit Mukherjee Dr. May 1999

International Joint Ventures And Technology Transfer In Developing Economies., Arijit Mukherjee Dr.

Doctoral Theses

Economic development is a continuous process of improvement and upgradation of the existing technological knowledge and their applications. This can be done in more than one way. Countries can acquire superior knowledge through a risky process of self-financed indigenous innovation. This may, however, been proved to be an expensive and time consuming process. Direct and indirect import of technologies are other ways of getting advanced knowledge. Technological change that has been taking place in most of the developing countries is partly the result of import of technologies from the industrially advanced economies. Multinational companies (MNCS) may potentially act as agents …


Engel Curve Estimation From Budget Data Relating To Short Reference Periods., Suchismita Ghosh Dr. May 1999

Engel Curve Estimation From Budget Data Relating To Short Reference Periods., Suchismita Ghosh Dr.

Doctoral Theses

The main motivation of the present dissertation is the estimation of engel elasticities of certain items of consumption after eliminating the possible effects of seasonal and other short-run fluctuations from household budget data. Indian budget data provided by the National Sample Survey Organization (NSSO), mainly relating to the 38th round (January - December, 1983), has been utilized for the study. Such data generally relate to a moving reference period of 'last 30 days' preceding the date of interview (also referred to as the last month reference period). The use of such a reference period introduces errors in observation in both …


Some Studies On Shape Of Dot Patterns., Anirban Ray Chaudhuri Dr. Feb 1999

Some Studies On Shape Of Dot Patterns., Anirban Ray Chaudhuri Dr.

Doctoral Theses

The important visual characteristics of an object are shape, size, color, brightness, contrast and texture. Of them, shape is a multidimensional concept that is difficult to define. It takes different meanings in different contexts. We try to explain it in terms of their attributes like elongation, roundness, and symmetry: although these terms do not capture the complete notion of shape.Perhaps Gestalt theory Koffka 351 is the first attempt to study the principles of visual perception in a systematic manner. The central concept of this theory is Gestalt' which means form or configuration. In this theory form is examined from physical. …


Time-Space Harmonic Polynomials For Stochastic Processes., Arindam Sengupta Dr. Feb 1999

Time-Space Harmonic Polynomials For Stochastic Processes., Arindam Sengupta Dr.

Doctoral Theses

The sequence of polynomials of a single variable known as the Hermite polynomialshala) = ), k21, (-1)* ha(z) =has many close links with the Normal distribution. Their association goes very doep, and extends to several connections bet ween the two-variable Hermite polynomialsHll, 2) = the(z/t), . k21.and the prime example of Gaussian processes, that is Brownian motion, as well. Much of this connection stems from what we term the time-space harmonic property of these polynomials for the Brownian motion process. An exact definition of this property follows later. A natural question that arises is, for stochastic processes in general, when …


Studies Of Supply Responses In Indian Agriculture: Some Models For Planning Rational Food Supply., Nilabja Ghosh Dr. Feb 1999

Studies Of Supply Responses In Indian Agriculture: Some Models For Planning Rational Food Supply., Nilabja Ghosh Dr.

Doctoral Theses

This thesis deals with food supply in a less developed country.In a world where social awareness together with technical progress is offering advances in all spheres of life, the persisting presence of hunger and malnutrition in any corner of the earth casts a shadow on all human achievements. It is said that over 800 million human beings in this world are suffering from hunger and a great majority of them live in Asia. Food problem has many dimensions (Timmer et al, 1983), but the solution lies mostly in adequate supply of foodgrains and proper distribution of the same. Any shortfall …


Pattern Classification Using Genetic Algorithms., Sanghamitra Bandyopadhyay Dr. Feb 1999

Pattern Classification Using Genetic Algorithms., Sanghamitra Bandyopadhyay Dr.

Doctoral Theses

Pattern recognition and machine learning form a major area of research and develop- ment activity that encompasses the processing of pictorial and other non-numerical information obtained from the interaction between science, technology and society. A motivation for the spurt of activity in this field is the need for people to com- municate with the computing machines in their natural mode of communication. Another important motivation is that the scientists are also concerned with the idea of designing and making intelligent machines that can carry out certain tasks that we human beings do. The most salient outcome of these is the …


Muyltivariate And Regression Analysis Based On The Geometry Of Data Clouds., Biman Chakraborty Dr. Feb 1999

Muyltivariate And Regression Analysis Based On The Geometry Of Data Clouds., Biman Chakraborty Dr.

Doctoral Theses

Median is a natural estimate of location of a data set, and there are several versions of inultivariate median studied in the literature, each of which is an interesting descriptive statistic for multivariate data and provides some nice geometric insights into the data cloud. One would expect that multidimensional median will be a natural estimate for the center of symmetry of a multivariate distribution. However, there is no unique concept of symmetry in multivariate problems. The center of symmetry can be defined in several ways there. For example, the d-dimensional random variable X is spherically symmetric about e €Rd if …


Essay On Deprivation, Poverty And Well-Being., Diganta Mukherjee Dr. Nov 1998

Essay On Deprivation, Poverty And Well-Being., Diganta Mukherjee Dr.

Doctoral Theses

Issues like inequity, deprivation and poverty have been a focus of interest for social scientists for a long time. The present thesis explores a few aspects of the above issues. It ermbodies the fruit of my intellectual perambulation in the Economic Research Unit of Indian Statistical Institute (ISI) during the years 1995 - 97. The text is divided into six chapters. The first chapter gives a general overview of different aspects of measuring inequality, deprivation and poverty. The second, third and fourth chapters take up the issue of deprivation measurement in detail. They contain discussions on deprivation ordering, indices and …


Construction Of Some Combinatorial Designs Arising Out Of Statistical Experiments., Tridib Kumar Dutta Dr. Sep 1998

Construction Of Some Combinatorial Designs Arising Out Of Statistical Experiments., Tridib Kumar Dutta Dr.

Doctoral Theses

Chis dissertation considers construction of two kinds of combi natorial sesigns as used by statisticians: repeated measurements designs (RMDS) and symmetric balanced squares (SBSS). 1.1. REPEATED MEASUREMENTS DESIGNS The researchers need to perform experiments where each experimental unit receives some or all of the treatments in an appropriate sequence over a number of successive periods. These designs are known by several names in the statistical 1iterature: repeated measurements designs, crossover or changeover designs, (multiple) time series designs, and before-after designs. If there are n experimental units 1,2, ... n, t treatments and p periods 0,1, .. .p-1, applied, then an …


Asymptotic Norming Properties And Related Themes., Sudeshna Basu Dr. Jul 1998

Asymptotic Norming Properties And Related Themes., Sudeshna Basu Dr.

Doctoral Theses

In the first part of this chapter, we explain the main theme of this thesis. The second part consists of some of the notions and results used in subsequent discussions.It is a very familiar fact that a point outside a (bounded) closed convex set in a Banach space can be separated from the latter by a hyperplane. One can ask whether the separation can be effected by disjoint balls. This is a typical example of a ball separation property, study of which has become important in Banach space theory. In this thesis, we study several such properties along with some …


On The Developement Of An Optical Character Recognition(Ocr) System For Printed Bangla Script., Umapada Pal Dr. Jun 1998

On The Developement Of An Optical Character Recognition(Ocr) System For Printed Bangla Script., Umapada Pal Dr.

Doctoral Theses

This thesis concerns OCR development of machine printed text in an Indian lan- guage, Bangla (Bengali) which is the fourthmost popular language in the world and the secondmost popular language in India.1.1 Optical Character Recognition Optical Character Recognition (OCR) is a process of automatic computer recog- nition of characters in optically scanned and digitized pages of text. OCR is ene of the most fascinating and challenging areas of pattern recognition with various practical applications. It can contribute tremendously to the advancement of an automation process and can improve the interface between man and machine in many applications, including office automation …


Neuro Fuzzy Reasoning For Pattern Classification And Object Recognition., Jayati Ghosh Dr. Mar 1998

Neuro Fuzzy Reasoning For Pattern Classification And Object Recognition., Jayati Ghosh Dr.

Doctoral Theses

In real world, pattern classification and object recognition problems are faced with fuzzi- ness that is connected with diverse facets of cognitive activity of the human being. An origin of sources of fuzziness is related to labels expressed in feature space as well as to labels of classes taken into account in classification and /or recognition procedures. Though a lot of scientific efforts have already been dedicated to pattern recognition problems, especially to classification procedures, still pattern recognition is confronted with a continuous challenge coming from a human being who can perform lot of ex- tremely complex classification tasks by …


On The Geometrisability Of Some Strongly Regular Graphs Related To Polar Spaces., Pratima Panigraphi Dr. Feb 1998

On The Geometrisability Of Some Strongly Regular Graphs Related To Polar Spaces., Pratima Panigraphi Dr.

Doctoral Theses

GraphsA graph G = (VE) consists of a finite set V and a subset E of ). (Here () denotes the set of all 2-subsets of V.) Elements of Vare called the vertices and the elements of E are called the edges of the graph. So Vis the vertex set and E is the edge set of the graph G. Two vertices a, y are said to be adjacent if the pair {a, y} is an edge; otherwise they are non-adjacent. If two vertices are adjacent then each is called a neighbour of the other vertex.Sometimes the edges of a …


Static Interconnection Networks And Parallel Algorithms For Efficient Problem Solving., T. Krishnan Dr. Feb 1998

Static Interconnection Networks And Parallel Algorithms For Efficient Problem Solving., T. Krishnan Dr.

Doctoral Theses

There is nothing more difficult to take in hand, more perilous to conduct, or more uncertain in its success, than to take the lead in the introduction of a new order of things.


Wiener Tauberian Theorems On Semisimple Lie Group., Rudra Pada Sarkar Dr. Feb 1998

Wiener Tauberian Theorems On Semisimple Lie Group., Rudra Pada Sarkar Dr.

Doctoral Theses

In their celebrated study of Harmonic analysis on semi-simple Lie groups Ehrenpreis and Mautner [E-M] noticed that the analogue of the claasical Wiener Tauberian theorem resting on the unitary dual does not hold for semisimple Lle groups. A simple proof of this fact due to M. Duflo appears in (H). Ehrenpreis and Mautner went on in (E-M] to formulate the problem on the commutative Banach algebra of the SO2(R)-biinvariant functions in L1(SL2(R))1, and obtained two different versions of the theorem involving, this time, the dual of the Banach algebra which includes, beside the unitary dual of G, a part of …


On Lipschitzian, And Connected Matrices In: Linear Complementarity Problem., Sriparna Bandyopadhyay Dr. Jan 1998

On Lipschitzian, And Connected Matrices In: Linear Complementarity Problem., Sriparna Bandyopadhyay Dr.

Doctoral Theses

This dissertation deals with a number of questions related to the linear complementarity problem (LCP). Given A ∈ Rn*n and q ∈ Rnthe LCP is to find a vector z ∈ R" such that Az+q ≥0,≥ and 2'(Az + 9) = 0. There is a vast literature on LCP developed during the last four decades. LCP plays a crucial role in the study of Mathematical Progranming from the point of view of algorithms as well as applications. The questions on existence and multiplicity of solutions in LCP has led researchers to introduce and study a variety of matrix classes. Most …


New Topologies And Parallel Algorithms For Static Interconnection Networks., Srabani Sen Gupta Dr. Dec 1997

New Topologies And Parallel Algorithms For Static Interconnection Networks., Srabani Sen Gupta Dr.

Doctoral Theses

Many real-life applications in the areas of signal processing, image processing, etc., require a large amount of fast computations to be performed. Although high speed powerful processors are currently available due to the phenomenal advances in VLSI technology, the increasing demand for massive real-time computations can not be met just by a uniprocessor system. One way of achieving the goal of fast computation is through parallel processing. In parallel processing, a problem is broken into several subproblems, which are distributed among different processors so that each of the processors can perform its task simultaneously. Main areas of recent research in …


Some Problems In Estimating Finite Population Total And Variance In Survey Sampling., Saswati Bhattacharya Dr. Dec 1997

Some Problems In Estimating Finite Population Total And Variance In Survey Sampling., Saswati Bhattacharya Dr.

Doctoral Theses

The problem of drawing inference concerning the parameters of a finite population of identifiable units has been increasingly engaging the attention of statisticians. The central problem here is to devise a suitable method of selecting a sample from the population and to employ an appropriate estimator to estimate the finite population total or mean. A consider- able progress in this field of study has been made and many authors have contributed towards the development of the theory in this aspect of the problem of statistical inferenceNumerous papers have been written covering the first aspect of the problem, namely, method of …


Pompeiu Problem And Analogues Of The Weiner-Tauberian Theorem For Certain Homogeneous Spaces., Rama Rawat Dr. Aug 1997

Pompeiu Problem And Analogues Of The Weiner-Tauberian Theorem For Certain Homogeneous Spaces., Rama Rawat Dr.

Doctoral Theses

Let G be a connected locally compact unimodular group acting transitively on a locally compact space X. For a function f on X and g € G, define of by 9f(x) = fA 9.a), a € X. One of the recurring themes in analysis is the question of when a function f in a given function space F(X) will have property that Span{gf : g € G} is dense in F(X). If X = R and G = R, the celebrated Wiener-Tauberian theorem answers this question completely for the space L1(R): The span of the translates of fE L1(R) is …


The Fixed Point Index As A Local Lefschetz Number., Neeta Pandey Dr. Feb 1997

The Fixed Point Index As A Local Lefschetz Number., Neeta Pandey Dr.

Doctoral Theses

In this thesis we defitne a class of self maps of connected compact polyhodza - those which prmserve erpanding directions - and define the fixed point indices of such maps at an isolated set of fixed points of the map as a local Lefschets rumber. Our definition uses simplicial approximations of the given map in the spirit of O Nell (I19| and Fournier (71) and is intrinsic so that it is computable.Let X be a connected compact polyhedron and f:X→ X be a map an X. The Lefscheta number L() of / is then defined to be ([13]),L) -E(-1)jTrace {, …


On Some Problems Related To Hermite And Laguerre Expansions., P. K. Ratnakumar Dr. Feb 1997

On Some Problems Related To Hermite And Laguerre Expansions., P. K. Ratnakumar Dr.

Doctoral Theses

The first three chapters of this thesis are concerned with the spherical means associated to the Hermite and Laguerre expansions. The study of spherical means has a very long history. The classic work of F. John deals with various applications of the spherical means to the theory of partial differential equations. They entered Fourier analysis with the celebrated theorem of E. Stein on spherical analogue of the Lebesgue differentiation theorem. Ever since they have appcared again and again in several areas of analysis like integral geometry, inversion of Fourier transforms and related arcas.


On Cvt Minimization In Single Machine Scheduling., D. K. Manna Dr. Feb 1997

On Cvt Minimization In Single Machine Scheduling., D. K. Manna Dr.

Doctoral Theses

Scheduling problens are quite common in real life. They arise whenever there is a need to plan execution of various tasks over time and therefore they play very important roles in commercial set-ups concerning manufacturing or service in the optimal use of resources and/or customers satisfaction. The theory of scheduling deals with the construction of suitable models and their analyses. Researchersattention was drawn to the study of scheduling problems using mathematical modeling, probably for the first time when Johnson (1954] published his famous work on flowshop problem. Since then, the study of scheduling problem and its context has gradually attracted …


Fourier Transforms Of Very Rapidly Decreasing Functions On Certain Lie Groups., M. Sundari Dr. Feb 1997

Fourier Transforms Of Very Rapidly Decreasing Functions On Certain Lie Groups., M. Sundari Dr.

Doctoral Theses

Recall that for a function f ϵ L1(Rn ), its Fourier transform fÌ‚ is definedby: fÌ‚ (ƹ) = ʃ Rnf(x)ei(ƹ,x)dx ( 0.1.1)where (.,.) denotes the standard inner product on Rn and dr the Lebesgue measure on Rn. A celebrated theorem of L. Schwartz asserts that a function f on Rn is rapidly decreasing (or in the Schwartz class ) if and only if its Fourier transform is rapidly decreasing . In sharp contrast to Schwartz s theorem, is a result due to Hardy ([18) which says that ʃ and fÌ‚ cannot both be very rapidly decreasing . More precisely, if …