Numerical modelling of the aluminium extrusion process

The extrusion of aluminium alloys involves the shaping of the product from an homogenised billet into a complex shape. In addition the properties of the extrudate are closely related to the processing parameters (temperature, stain rate, and material morphology). Since all the parameters vary throughout the ram stroke and throughout the billet the prediction of the condition of the extrudate is complex. In this study the analysis is accomplished by the use of finite element analysis coupled with sub-illodelling of the structural features. The study is extended to include the lieat-treatment process necessary for precipitation hardened alloys subsequent to the process. The author has published these results in a number of learned journals and these are given in Appendix. After a concise introduction and crirical literature review chapter3 analyses the basic operation of the finite element package(FEM) discussing the procedures involved, the equilibrium equations and the more practical aspect of the mesh morphology and size. Finite Element analysis and material structural models have been integrated using parallel processing technology and program sub-routines. In this section the external inputs are also defined paying particular attention to the friction conditions and the constitutive equations. The thesis then proceeds to describe and analyse the integrated modelling of the process necessary to introduce the user introduction of the equations necessary to produce a comprehensive analysis of the material structural problems. This includes the cellular automata teclu-iiques. Various complex extrusion geometries are analysed and the effects of scaling considered. Development of the extrudate surface and criteria for ptedicting this important feature are coinprehebsivcly covered in chapter 5 whilst chapter 6 considers some special technologies such as the use of pockets to obtain homogenous structures. Isothermal extrusion is also included in this section

Numerical modelling of the aluminium extrusion process

The extrusion of aluminium alloys involves the shaping of the product from an homogenised billet into a complex shape. In addition the properties of the extrudate are closely related to the processing parameters (temperature, stain rate, and material morphology). Since all the parameters vary throughout the ram stroke and throughout the billet the prediction of the condition of the extrudate is complex. In this study the analysis is accomplished by the use of finite element analysis coupled with sub-illodelling of the structural features. The study is extended to include the lieat-treatment process necessary for precipitation hardened alloys subsequent to the process. The author has published these results in a number of learned journals and these are given in Appendix. After a concise introduction and crirical literature review chapter3 analyses the basic operation of the finite element package(FEM) discussing the procedures involved, the equilibrium equations and the more practical aspect of the mesh morphology and size. Finite Element analysis and material structural models have been integrated using parallel processing technology and program sub-routines. In this section the external inputs are also defined paying particular attention to the friction conditions and the constitutive equations. The thesis then proceeds to describe and analyse the integrated modelling of the process necessary to introduce the user introduction of the equations necessary to produce a comprehensive analysis of the material structural problems. This includes the cellular automata teclu-iiques. Various complex extrusion geometries are analysed and the effects of scaling considered. Development of the extrudate surface and criteria for ptedicting this important feature are coinprehebsivcly covered in chapter 5 whilst chapter 6 considers some special technologies such as the use of pockets to obtain homogenous structures. Isothermal extrusion is also included in this section.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

A thirty channel real time audio analyzer and its applications

Ph.D.Eugene T. Patronis, Jr

Ideology, Mimesis, Fantasy

This study of German fiction about America in the nineteenth century concentrates in detail on three writers: Charles Sealsfield (Carl Postl, 1793–1864), an escaped Moravian monk who came to New Orleans in 1823 and wrote the first major German novels about the United States; Friedrich Gerstäcker (1816–1872), who, among his many experiences in America as a young man, lived as a backwoodsman in Arkansas and who later produced a large body of fiction, travel reportage, and emigration advice; and Karl May (1842–1912), who, though he knew nothing about America beyond what he could read in books, wrote famous adventure stories set in an imaginary West and became the best-selling writer in the German language. Sammons provides biographies of the authors and discusses how each differs in their mimetic and ideological approach. He pays particular attention to how the authors address issues of race, gender and politics in the United States. Sammons interweaves his discussion of these three writers with excurses into the emergence of the German Western and anti-Americanism in German fiction

Reading, Travel, and the Pedagogy of Growing Up in Late Nineteenth-Century Germany

This project brings together the domestic world of young adult reading with the foreign world of international travel that informed German experience at the end of the nineteenth century. By uniting these two ostensibly disparate realms under one interpretive frame, I offer a new perspective on the theory and practice of young-adult reading at the turn of the last century and the role this reading about travel played in the development of sense of self and sense of place within a national body. My analysis reads specific youth literature about travel: Brigitte Augusti, Friedrich Pajeken) against depictions of youth reading about the wider world in the now-canonical texts of Realism: Wilhelm Raabe). I find two simultaneously existing, yet, contradictory strands of discourse that resonate even today: On the one hand, an exuberance for newfound mobility in a now-global world and its endless possibilities; on the other, a skepticism about the potential of mobility to solve the world\u27s problems. I examine how these tensions interact through diverse models of pedagogy portrayed in and as texts and map reading and travel within discourses about young people\u27s integration into an adult world. Through historical study and literary interpretation of cultural production of the 1880s and 1890s, this project ultimately seeks broad insights into the pedagogical and psychological value of the intersections of travel and reading, and, in doing so, attempts to answer some of the enduring questions central to our mission as scholars and teachers of foreign language and culture within the humanities

Ecological studies of the breeding sites and reproductive strategies of domestic species of Drosophila

The ecology and reproductive strategies of seven species of domestic Drosophila were examined at a wholesale fruit and vegetable market. The seasonal abundance of adult Drosophila was investigated using baited traps. The value of different trapping methods was discussed. Drosophila were reared from different fruits and vegetables brought back from the market to the laboratory. D. melanogaster, D. simulans and D. subobscura nearly always emerged from fermenting fruits, D. busckii specialised on decaying vegetables, and D. immigrans and D. hydei were generalists. Within the groups, fermenting fruit and decaying vegetables there was considerable overlap of breeding sites. Some of the factors which might influence breeding site preferences were investigated in the field and in the laboratory. Both selection of breeding sites by ovipositing females and differential survival of the larvae seem to be important. Unlike other species of Drosophila the domestic species do not seem to separate their feeding and breeding sites. D. immigrans, which frequently breeds in citrus fruits, was found to be particularly associated with these fruits when they were infected with the mould, Penicillium. Other species emerged more often from uninfected fruit. There may be a long standing evolutionary relationship between D. immigrans, citrus fruits and Penicillium. The body size of D. melanogaster, caught in traps, was found to change in a regular way during the season. This was partly an effect of temperature, but partly due to intraspecific competition at the highest population densities. Intraspecific competition is unimportant in the other species, though some species suffered from interspecific competition with D. melanogaster. The reproductive strategies of the seven Drosophila species were examined. They fell into two groups, large species with large clutches of small eggs, and small species with small clutches of large eggs. These strategies are not consistent with r— and K— selection theory, but may have been linked to the predictability of finding breeding sites. The ecology of domestic species of Drosophila was discussed with reference to current theories of population regulation

Peter Altenberg: a neglected writer of the Viennese Jahrhundertwende

This thesis presents a revaluation of the works of Peter Altenberg, a neglected writer of the Viennese Jahrhundertwende. Although largely ignored by literary criticism, Altenberg's writing influenced German Expressionist authors as well as such major figures as Musil, Rilke and Kafka.The text is divided into six sections. (The confusion and profusion of topics and ideas in Altenberq's work mean that my divisions may appear arbitrary at times. However, they broadly represent the most important aspects of Altenberg's thought, literary theory and practice.) In order to reveal the development of Altenberg's thought, individual topics are usually discussed from a chronological perspective.In section 1 I present Altenberg in the context of Vienna 1900 and establish his relationship with Naturalist writers. Section 2 thematicises Altenberg's image of man¬ kind and, more specifically, his presentation and assessment of the existential dilemma of the modern urban dweller. Section 3 comprises a critical analysis of Altenberg's con¬ ception of womankind and his "Frauenkult". Section 4 is devoted to a detailed examination of Altenberg's sociocultural critique which, I propose, is inspired by that of Friedrich Nietzsche and Richard Wagner. Section 5 sets out Altenberg's blueprint for a new society, or alternative social order, based on his ideals of freedom, nobility and naturalness. In section 6 I deal with aspects of Altenberg's literary theory and practice; I discuss the formal elements in his work as well as the principle of aesthetic reductionism which he pioneered

Studies in the German Drama

Sixteen of his former colleagues and students join in this volume in honoring Walter Silz. Concentrating on a single theme—the German drama—this volume contains essays and interpretations of plays ranging from Hrotsvit von Gandersheim to Bertolt Brecht. Eight of the sixteen essays deal with dramas from the area of Silz's main concentration—the nineteenth century. Also included are a tribute to Silz and a bibliography of his writings

Ideology, Mimesis, Fantasy: Charles Sealsfield, Friedrich Gerstäcker, Karl May, and Other German Novelists of America

This study of German fiction about America in the nineteenth century concentrates in detail on three writers: Charles Sealsfield (Carl Postl, 1793–1864), an escaped Moravian monk who came to New Orleans in 1823 and wrote the first major German novels about the United States; Friedrich Gerstäcker (1816–1872), who, among his many experiences in America as a young man, lived as a backwoodsman in Arkansas and who later produced a large body of fiction, travel reportage, and emigration advice; and Karl May (1842–1912), who, though he knew nothing about America beyond what he could read in books, wrote famous adventure stories set in an imaginary West and became the best-selling writer in the German language. Sammons provides biographies of the authors and discusses how each differs in their mimetic and ideological approach. He pays particular attention to how the authors address issues of race, gender and politics in the United States. Sammons interweaves his discussion of these three writers with excurses into the emergence of the German Western and anti-Americanism in German fiction