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On Image Segmentation Using Neural Networks And Fuzzy Sets., Ashish Ghosh Dr.
On Image Segmentation Using Neural Networks And Fuzzy Sets., Ashish Ghosh Dr.
Doctoral Theses
During the last five decades or even more a large number of researchers are trying to design intelligent systems to perform tasks at which human beings are more efficient at present. One of the most important behavioral tasks in which human beings show their expertise is image analysis or recognition; where a large amount of pictorial data is processed in a very small amount of time (called real time). Widespread attempts have been made to develop intelligent systems (under different names, like pattern recognition system, image under- standing system, computer vision system etc.) for pictorial pattern analysis and recognition. The …
On Markov Processes Charecterised Via Martingale Problem., Abhay G. Bhatt Dr.
On Markov Processes Charecterised Via Martingale Problem., Abhay G. Bhatt Dr.
Doctoral Theses
Martingale approach to the study of finite dimensional diffusions was initiated by Stroock-Varadhan, who coined the term martingale problem. Their success led to a similar approach being used to study Markov processes occuring in other areas such as infinite particle systems, branching processes, genetic models, density dependent population processes, random evolutions etc.Suppose X is a Markov process corresponding to a semigroup (T)e20 with generator L. Then all the information about X is contained in L. We also have thatMf(t) := f(X(t)) – ∫t0 Lf(X(s))dsis a martingale for every f ∈ D(L). i.e. X is a solution to the martingale problem …
Coxeter Groups And Positive Matrices., Arbind Kumar Lal Dr.
Coxeter Groups And Positive Matrices., Arbind Kumar Lal Dr.
Doctoral Theses
In this thesis, we study positive matrices (matrices whose entries are nonnegative as well as matrices which are positive semidefinite) with Coxeter groups as the underlying theme. For an exposition on Coxeter groups see Humphreys (1990).A Cozeter system consists of a pair (W, s); where W is a group and S is a set which consists of the generators of the group W. The elements of the set S have only the relations of the form (ss')m(s.) 1; where m(s, s) 1, m(s, s') = m(s,s) 2 2 for s s in S. In case no relation occurs for a …
Survival Function Estimation Under Random Censoring., Debajyoti Dhar Dr.
Survival Function Estimation Under Random Censoring., Debajyoti Dhar Dr.
Doctoral Theses
Statistical methods for life data analysis are used to measure, compare and predict characteristics of the distribution of the time to some particular event of interest, often called failure after a length of time, called life time. Failure can occur at most once for an individual. Examples of failure time include the lifetimes of machine components in industrial reliability, the duration of strikes or periods of unemployment in economic studies, the time taken by subjects to complete specified tasks in psychological experiments, the lengths of tracks photographic plates in particle physics and the on survival time of patients in clinical …
Generalised Inverses Of Matrices Over Rings., K. Manjunatha Prasad Dr.
Generalised Inverses Of Matrices Over Rings., K. Manjunatha Prasad Dr.
Doctoral Theses
For a complex or a real matrix A, a matrix G is called a generalized inverse ( or g-inverse) of A if(1) AGA = AThe theory of generalized inverses over the field of complex numbers is well- studied in the literature (see (2), (11), (33), and (62) for an extensive bibliography). Even for matrices over a general field the above equation carries over. In fact, even for matrices over a general ring, equation (1) makes sense. Hence one can talk of g-inverses of matrices over general rings. Some work on g-inverses of matrices over fields also can be found in …
On Some Measurement Problem In Economics., Nachiketa Chattopadhyay Dr.
On Some Measurement Problem In Economics., Nachiketa Chattopadhyay Dr.
Doctoral Theses
In many branches of economie theory, quantitative relationships play a major role. Translating actions of individuals or groups of individuals, in the various soci- etal processes of production, distribution or consumption, into measurable or quan- tifiable notions has been one of the most important problems. When we take the society as a whole, diverse economic activities of ita memhers need to be collectively presented and it has given rise to interesting aggregation problems. Economists have tried to solve these problems by constructing social index numbers. Simi- larly, quantifying actions of individual units (for example, a firm /a consumer) has brought …
Curriculum Based Measurement And Portfolio Assessment: An Effective Evaluation System, Johanna Roberts
Curriculum Based Measurement And Portfolio Assessment: An Effective Evaluation System, Johanna Roberts
All Graduate Projects
The researcher reviewed current literature regarding curriculum based assessment, curriculum based measurement (CBM) and portfolio assessment. The researcher developed a curriculum based measurement for kindergarten prereading and premath skills as a part of a portfolio system. A first grade math curriculum based measurement was designed collaboratively with two first grade teachers. A beginning reading assessment was also designed for the first grade. Results showed that a portfolio assessment with CBM's is an effective evaluation tool.
On The Characterization Of Finite Dimensional Hida Distributions., Kyoung Sim Lee
On The Characterization Of Finite Dimensional Hida Distributions., Kyoung Sim Lee
LSU Historical Dissertations and Theses
The mathematical framework of white noise analysis is based on an infinite dimensional analogue of the Schwartz distribution theory. The Lebesgue measure on $\IR\sp{k}$ is replaced with standard Gaussian measures $\mu$ on infinite dimensional spaces. There is an infinite dimensional analogue $({\cal E})\subset L\sp2({\cal E}\sp*,\mu)\subset({\cal E})\sp*$ of a Gel'fand triple ${\cal E}\subset E\subset{\cal E}\sp*$ which is obtained from ${\cal S}(\IR\sp{k})\subset L\sp2(\IR\sp{k})\subset{\cal S}\sp*(\IR\sp{k})$ in a general setup. There are spaces $({\cal E}\sp\beta),({\cal E}\sp\beta)\sp*, \beta\in\lbrack 0,1)$ with $({\cal E}\sp\beta)\subset({\cal E})\subset L\sp2({\cal E}\sp*,\mu)\subset({\cal E})\sp*\subset({\cal E}\sp\beta)\sp*.$. The compositions of Schwartz distributions and Gaussian random variables have been discussed. A new Gel'fand triple ${\cal H}(\IR\sp{k})\subset{\cal …
Split Abelian Extensions Of Calgebras., Mark Andrew Curole
Split Abelian Extensions Of Calgebras., Mark Andrew Curole
LSU Historical Dissertations and Theses
It is shown that the C* algebra of a groupoid with Haar system has a natural split abelian extension. For a split abelian extension of a C* algebra it is shown that all representations of the original algebra extend to the split abelian extension. Under a reasonable assumption it is shown that states extend to a split abelian extension. Definitions for quasi-invariant and ergodic measures are given for split abelian extension of C* algebras, and it is shown when the split abelian extension is the natural extension of the C* algebra of a groupoid with Haar system that these definitions …
Linkage By Generically Gorenstein Cohen-Macaulay Ideals., Heath Mayall Martin
Linkage By Generically Gorenstein Cohen-Macaulay Ideals., Heath Mayall Martin
LSU Historical Dissertations and Theses
In a Gorenstein local ring R, two ideals A and B are said to be linked by an ideal I if the two relations A = (I: B) and B = (I: A) hold. In the case that I is a complete intersection, or a Gorenstein ideal, it is known that linkage preserves the Cohen-Macaulay property. That is, if A is a Cohen-Macaulay ideal, then so is B. However, if I is allowed to be a generically Gorenstein, Cohen-Macaulay ideal, easy examples show that this type of linkage does not preserve the Cohen-Macaulay property. The primary purpose of this work …
Hankel Operators On Hilbert Spaces, Pachara Wanpen
Hankel Operators On Hilbert Spaces, Pachara Wanpen
Doctoral Dissertations
In this paper we consider the Hankel operators from two points of view. On one hand the Hankel operator is induced by the coefficient sequence $a\sb0,a\sb1,a\sb2,\...$ and operates on a Hilbert space $H\sp2(\beta)$ with $\Sigma\sbsp{n=0}{\infty}\ \beta(n)\sp2 < \infty.$ In this situation we can find necessary conditions and sufficient conditions for the Hankel operator to be bounded. However, with compactness and Hilbert-Schmidt we can get only sufficient conditions. On the other hand we look at the Hankel operator $H\sb{f,\alpha}$ and little Hankel operator $h\sb{f,\alpha},$ with symbol function f, that operates on a weighted Bergman space. In this case we can determine bounded, compact, Hilbert Schmidt, or trace class operators of the Hankel operator $H\sb{f}$ and $h\sb{f,\alpha}.$ We also give a good estimate of bounded norm of little Hankel operators with a particular symbol function $f = z\bar g$ where g is in the Bloch space.
Approximate Equivalence Invon Neumann Algebras, Hui-Ru Ding
Approximate Equivalence Invon Neumann Algebras, Hui-Ru Ding
Doctoral Dissertations
In this paper we investigate approximate equivalence in von Neumann algebras. We find a necessary and sufficient condition for two normal operators to be approximately equivalent in any von Neumann algebra ${\cal R}$ acting on a separable Hilbert space H with unitaries in ${\cal R}.$ For the approximate equivalence of two unital representations from a given C$\*$-algebra to any von Neumann algebra acting on a separable Hilbert space, we find the necessary condition for the general case. Finally we investigate an interesting class of C$\*$-algebras, closed under direct sum, direct limit and quotient map, which contains C(X) and $M\sb{n}(A),$ where …
The Congruence Extension Property, The Ideal Extension Property, And Ideal Semigroups., Karen Dommert Aucoin
The Congruence Extension Property, The Ideal Extension Property, And Ideal Semigroups., Karen Dommert Aucoin
LSU Historical Dissertations and Theses
A semigroup has the congruence extension property (CEP) provided that each congruence on each subsemigroup of S extends to a congruence on S. The ideal extension property (IEP) for semigroups is defined analogously. A characterization of commutative semigroups with IEP is given in terms of multiplicative conditions within and between the archimedean components of the semigroup. A similar characterization of commutative semigroups with CEP is sought. Toward this end, archimedean semigroups with CEP are characterized in terms of multiplicative structure and a number of necessary conditions on multiplication between the archimedean components of a commutative semigroup with CEP are established. …
The Congruence Extension Property And Related Topics In Semigroups., Jill Ann Dumesnil
The Congruence Extension Property And Related Topics In Semigroups., Jill Ann Dumesnil
LSU Historical Dissertations and Theses
A semigroup has the congruence extension property (CEP) provided that each congruence on each subsemigroup can be extended to a congruence on the semi-group. This property, the ideal extension property (IEP), and other related concepts are studied from both an algebraic and a topological perspective in this work. A characterization of semigroups with CEP is given in terms of the lattice of congruences. A similar result is obtained for IEP. Semigroups in which the relation "is an ideal of" is transitive (t-semigroups) are explored. It is shown that each of CEP and IEP implies this condition and that these are …
A Study Of The Benefits Of Reflection By Journal Writing In Mathematical Learning And Attitudes In The Primary School, Sally Edmonds
A Study Of The Benefits Of Reflection By Journal Writing In Mathematical Learning And Attitudes In The Primary School, Sally Edmonds
Theses : Honours
This descriptive study examines journal writing for the purpose of identifying aspects of children's mathematical reflective ability. It was hypothesised that encouragement to engage with the process of mathematics by reflective writing would reveal and assist learning, and give children a vehicle through which they could express their attitudes about the mathematics they were learning. The aim of this study was to find answers to the following question: How does the keeping of a mathematical journal reveal children's understandings of the mathematics they are learning? Other questions related to the study were: -What evidence is there from the journals about …
Models For Steady State Flow Past A Cylinder, Sergio J. D'Alessio
Models For Steady State Flow Past A Cylinder, Sergio J. D'Alessio
Digitized Theses
Three steady state models for determining the flow of a viscous incompressible Newtonian isothermal fluid past a two-dimensional cylindrical object are proposed. These models offer numerical methods of solving the governing Navier-Stokes equations as well as a mathematical understanding of the nature of the flow.;In the first model, the behaviour of the vorticity is patterned for both large and small distances by expressing the vorticity as {dollar}\zeta\ =\ \Phi\rm e\sp{lcub}\rm F{rcub}{dollar} with F chosen to accommodate both boundary-layer and wake theory. The resulting equations are then solved by finite differences and by the method of Dennis and Chang (1970).;The second …
Using Hypermedia To Improve The Dissemination And Accessibility Of Syllabus Documents With Particular Reference To Primary Mathematics, Alistair B. Campbell
Using Hypermedia To Improve The Dissemination And Accessibility Of Syllabus Documents With Particular Reference To Primary Mathematics, Alistair B. Campbell
Theses: Doctorates and Masters
The fundamental question that this study set out to investigate was: Can the advantages of hypermedia be extended to curriculum materials that are for the sole use of teachers? To consider this question, three areas needed to be investigated: hypermedia (the medium); teachers (the target) and curriculum documents (the content). Hypermedia has a long history dating back to Bush (1986) who in 1945 imagined his Memex system as building information trails between ideas. However, it was not until the mid 1980s that technology caught up with the theory and hypermedia came of age. The evaluation of hypermedia documents is still …
Hydrodynamic And Electrohydrodynamic Instability Of Shear Flows And The Numerical Simulation Of Viscous Droplets, Kenzu Abdella
Hydrodynamic And Electrohydrodynamic Instability Of Shear Flows And The Numerical Simulation Of Viscous Droplets, Kenzu Abdella
Digitized Theses
In this thesis, we investigate three fluid dynamic problems involving various physical mechanisms which exhibit interfacial instability. These problems have wide ranging industrial, scientific and engineering applications.;In the first problem, we investigate the linear stability of the unbounded Couette flow of two fluids separated by a plane interface. The exact dispersion relation is solved asymptotically and numerically to analyze the effects of the four stability parameters of the flow; the ratio of the viscosities, the ratio of the density, the surface tension and gravity. While our results confirm most of the earlier reported theories involving shear flows of fluids of …