Documents disponibles chez cet éditeur

Connectivity, independent sets and maximal circuits in undirected graphs / Ahmed Ainouche

Public ISBD Titre : Connectivity, independent sets and maximal circuits in undirected graphs Type de document : texte imprimé Auteurs : Ahmed Ainouche, Auteur ; Nicos Christofides, Directeur de thèse Editeur : London : [s.n.] Année de publication : 1980 Importance : 192 f. Présentation : ill. Format : 30 cm. Note générale : PhD Thesis: Management science : University of London : 1980 Bibliogr. en fin de chapitre Langues : Anglais (eng) Mots-clés : Connectivity Independent  sets Maximal  circuits Undirected  graphs Index. décimale : D002580 Résumé : This thesis deals with (i) finding sufficient conditions for the existence of hamiltonian circuits (or paths) in undirected graphs, and (ii) the derivation of upper and lower bounds on the connectivity and independence number of a graph. (i). A : New results are derived giving sufficient conditions for the existence of hamiltonian circuits in undirected graphs. These results are stronger than the existing well known ones (eg : those of las vergnas, chvatal, bondy etc...). Some of these results are of the "closure" type and dominate the bondy-chvàtal closure. Most of the new results (both of the closure and global form) involve conditions on the independece number of the graph (or slight variations thereof). Thus a degree of unification is achieved among the known and new conditions for the existence of hamiltonian circuits in graphs. Connectivity, independent sets and maximal circuits in undirected graphs [texte imprimé] / Ahmed Ainouche, Auteur ; Nicos Christofides, Directeur de thèse . - London : [s.n.], 1980 . - 192 f. : ill. ; 30 cm. PhD Thesis: Management science : University of London : 1980 Bibliogr. en fin de chapitre Langues : Anglais (eng) Mots-clés : Connectivity Independent  sets Maximal  circuits Undirected  graphs Index. décimale : D002580 Résumé : This thesis deals with (i) finding sufficient conditions for the existence of hamiltonian circuits (or paths) in undirected graphs, and (ii) the derivation of upper and lower bounds on the connectivity and independence number of a graph. (i). A : New results are derived giving sufficient conditions for the existence of hamiltonian circuits in undirected graphs. These results are stronger than the existing well known ones (eg : those of las vergnas, chvatal, bondy etc...). Some of these results are of the "closure" type and dominate the bondy-chvàtal closure. Most of the new results (both of the closure and global form) involve conditions on the independece number of the graph (or slight variations thereof). Thus a degree of unification is achieved among the known and new conditions for the existence of hamiltonian circuits in graphs.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
D002580	D002580	Papier	Bibliothèque centrale	Thèse de Doctorat	Disponible

Numerical methods for second order parabolic partial differential equations / Zoulikha Zaidi ep Otmani

Public ISBD Titre : Numerical methods for second order parabolic partial differential equations Type de document : texte imprimé Auteurs : Zoulikha Zaidi ep Otmani, Auteur ; E.H. Twizell, Directeur de thèse Editeur : London : [s.n.] Année de publication : 1986 Importance : 172 f. Présentation : ill. Format : 30 cm. Note générale : Master Thesis : Mathematics : The university of West London : 1986 Bibliogr. f. 170 - 172 Langues : Anglais (eng) Mots-clés : Numerical Methods Parabolic  partial Differential  equations Index. décimale : Ms01786 Résumé : The thesis develops a number of numerical methods for solving first order ordinary differential equations. These ordinary differential equations arise when secind order difference operators are used to replace the space derivatives of second order parabolic partial differential equations in one and two space variables. Our main concern in this thesis is not to improve the accuracy with respect to the space discretization process, but to explore the possibility of improving the accuracy with respect to the temporal discretization, achieving up to fourth order accuracy. Higher accuracy could of course be achieved when replacing the exponential function by its higher pade approximants but then the solution would be expensive. It is shown that I0-stable methods are to be preferred to A0-stable schemes when high frequency components in the numerical solution are expected. Emphasis is placed throughout on the cost of implementing each method by counting the number of arithmetic operations and CPU time to evaluate the solution at a certain time, using model problems from the literature. Numerical methods for second order parabolic partial differential equations [texte imprimé] / Zoulikha Zaidi ep Otmani, Auteur ; E.H. Twizell, Directeur de thèse . - London : [s.n.], 1986 . - 172 f. : ill. ; 30 cm. Master Thesis : Mathematics : The university of West London : 1986 Bibliogr. f. 170 - 172 Langues : Anglais (eng) Mots-clés : Numerical Methods Parabolic  partial Differential  equations Index. décimale : Ms01786 Résumé : The thesis develops a number of numerical methods for solving first order ordinary differential equations. These ordinary differential equations arise when secind order difference operators are used to replace the space derivatives of second order parabolic partial differential equations in one and two space variables. Our main concern in this thesis is not to improve the accuracy with respect to the space discretization process, but to explore the possibility of improving the accuracy with respect to the temporal discretization, achieving up to fourth order accuracy. Higher accuracy could of course be achieved when replacing the exponential function by its higher pade approximants but then the solution would be expensive. It is shown that I0-stable methods are to be preferred to A0-stable schemes when high frequency components in the numerical solution are expected. Emphasis is placed throughout on the cost of implementing each method by counting the number of arithmetic operations and CPU time to evaluate the solution at a certain time, using model problems from the literature.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
Ms01786	Ms01786	Papier	Bibliothèque centrale	Mémoire de Master	Disponible

Optimal stopping rules in oil exploration / Lakdere Benkherouf

Public ISBD Titre : Optimal stopping rules in oil exploration Type de document : texte imprimé Auteurs : Lakdere Benkherouf, Auteur ; J.A. Bather, Directeur de thèse Editeur : London : [s.n.] Année de publication : 1988 Importance : 133 f. Présentation : ill. Format : 30 cm. Note générale : PhD Thesis: Mathematics : London, Imperial college of science and technology : 1988 Bibliogr. f. 131 - 133 Langues : Anglais (eng) Mots-clés : Optimal  --  stopping  rules Oil  --  exploration Index. décimale : D000388 Résumé : In the thesis, we are concerned with obtaining optimal strategies for drilling in oil exploration. The criterion for optimality is the maximum expected return. In the first part of the thesis, a simple bayesian model for oil exploration is introduced. A condition on the way successes and failures affect the prior distribution implies a certain form of the detection mechanism. It is shown that the problem reduces to an optimal stopping problem. Three new families of distributions are obtained with generating functions related to classical work on partitions of integers. By using such distributions and simple mixtures of them as priors, the stopping problem can be solved explicitly. This leads to the construction of simple strategies and their effectiveness is demonstrated by evaluating suitable operating characteristics. Then, the distribution representing the number of undiscovered fields is approximated by one of the new distributions obtained in the first part and the approximate stopping problem is investigated. Optimal stopping rules in oil exploration [texte imprimé] / Lakdere Benkherouf, Auteur ; J.A. Bather, Directeur de thèse . - London : [s.n.], 1988 . - 133 f. : ill. ; 30 cm. PhD Thesis: Mathematics : London, Imperial college of science and technology : 1988 Bibliogr. f. 131 - 133 Langues : Anglais (eng) Mots-clés : Optimal  --  stopping  rules Oil  --  exploration Index. décimale : D000388 Résumé : In the thesis, we are concerned with obtaining optimal strategies for drilling in oil exploration. The criterion for optimality is the maximum expected return. In the first part of the thesis, a simple bayesian model for oil exploration is introduced. A condition on the way successes and failures affect the prior distribution implies a certain form of the detection mechanism. It is shown that the problem reduces to an optimal stopping problem. Three new families of distributions are obtained with generating functions related to classical work on partitions of integers. By using such distributions and simple mixtures of them as priors, the stopping problem can be solved explicitly. This leads to the construction of simple strategies and their effectiveness is demonstrated by evaluating suitable operating characteristics. Then, the distribution representing the number of undiscovered fields is approximated by one of the new distributions obtained in the first part and the approximate stopping problem is investigated.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
D000388	D000388	Papier	Bibliothèque centrale	Thèse de Doctorat	Disponible

Operator theory in the schatten classes / A. Abdessemed

Public ISBD Titre : Operator theory in the schatten classes Type de document : texte imprimé Auteurs : A. Abdessemed, Auteur ; E.B. Davies, Directeur de thèse Editeur : London : [s.n.] Année de publication : 1988 Importance : 134 f. Présentation : ill. Format : 30 cm Note générale : PhD Thesis : Mathematics : University of London : 1988 Bibliogr. f. 128 - 134 Langues : Anglais (eng) Mots-clés : Operator Theory Schatten Classes Index. décimale : D000588 Résumé : The thesis is accordingly divided into three chapters. Chapter one is an exposition of the theory of the schatten classes, or ep classes. As we advance through the chapter, the main results and theorems are developed. They represent background for the elaborations of the following chapters. The theory is recent and is still under research investigations. For this reason, we tried to be faithful by including some research work carried out in this field. Operator theory in the schatten classes [texte imprimé] / A. Abdessemed, Auteur ; E.B. Davies, Directeur de thèse . - London : [s.n.], 1988 . - 134 f. : ill. ; 30 cm. PhD Thesis : Mathematics : University of London : 1988 Bibliogr. f. 128 - 134 Langues : Anglais (eng) Mots-clés : Operator Theory Schatten Classes Index. décimale : D000588 Résumé : The thesis is accordingly divided into three chapters. Chapter one is an exposition of the theory of the schatten classes, or ep classes. As we advance through the chapter, the main results and theorems are developed. They represent background for the elaborations of the following chapters. The theory is recent and is still under research investigations. For this reason, we tried to be faithful by including some research work carried out in this field.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
D000588	D000588	Papier	Bibliothèque centrale	Thèse de Doctorat	Disponible

Program to aid the teaching of pointers and the heap / Smaine Nasr-Eddine Bouzenada

Public ISBD Titre : Program to aid the teaching of pointers and the heap Type de document : texte imprimé Auteurs : Smaine Nasr-Eddine Bouzenada, Auteur ; I.R. Maccallum, Directeur de thèse ; D. Lyons, Directeur de thèse Editeur : London : [s.n.] Année de publication : 1984 Importance : 162 f. Présentation : ill. Format : 30 cm. Note générale : Master Thesis : Computer science : London, University of Essex : 1984 Bibliogr. f. 161 - 162 . Appendix f. 96 - 160 Langues : Anglais (eng) Mots-clés : Pointers Heap CAL Pascal Index. décimale : Ms01684 Résumé : Computer aided learning (CAL) has been available since the early days of computing. It can be used to teach concepts and practical skills that sometimes requires time consuming individual tuition, or difficult textbook study. The use of graphics in CAL systems can not only add a new dimension but can also be excising and dynamic. Many CAL programs are directed at science based studies (learning diffraction in chemistry, or calculus in mathematics etc.) Harris (1984) In this dissertation, we shall describe two main CAL programs, one oriented on teaching "pointers" in UCSD pascal and the second explains the "heap" and its management. These programs are to be designed and implemented on the vector under UCSD pascal. Program to aid the teaching of pointers and the heap [texte imprimé] / Smaine Nasr-Eddine Bouzenada, Auteur ; I.R. Maccallum, Directeur de thèse ; D. Lyons, Directeur de thèse . - London : [s.n.], 1984 . - 162 f. : ill. ; 30 cm. Master Thesis : Computer science : London, University of Essex : 1984 Bibliogr. f. 161 - 162 . Appendix f. 96 - 160 Langues : Anglais (eng) Mots-clés : Pointers Heap CAL Pascal Index. décimale : Ms01684 Résumé : Computer aided learning (CAL) has been available since the early days of computing. It can be used to teach concepts and practical skills that sometimes requires time consuming individual tuition, or difficult textbook study. The use of graphics in CAL systems can not only add a new dimension but can also be excising and dynamic. Many CAL programs are directed at science based studies (learning diffraction in chemistry, or calculus in mathematics etc.) Harris (1984) In this dissertation, we shall describe two main CAL programs, one oriented on teaching "pointers" in UCSD pascal and the second explains the "heap" and its management. These programs are to be designed and implemented on the vector under UCSD pascal.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
Ms01684	Ms01684	Papier	Bibliothèque centrale	Mémoire de Master	Disponible