This thesis concerned the design and implementation of an extensible computer language for microcomputer users. The language was shown to provide a minimal set of features which can be extended toward particular applications. The interactive nature of the language was discussed, along with a description of each language feature.Also presented were implementation specifics involving the use of a technique called threaded code. Motivations for the use of extensible languages were discussed, along with suggestions for further extensions and applications. / School of Music

Acoustic horns are used in musical instruments and loudspeakers in order to provide an impedance match between an acoustic source and the surrounding air. The aim of this study is to develop numerical tools for the analysis and optimisation of such horns, with respect to their input impedance spectra. Important effects such as visco-thermal damping and modal conversion are shown to be localised to different parts of a typical brass instrument. This makes it possible to construct hybrid methods that apply different numerical techniques in different parts of the instrument. Narrow and slowly flaring parts are modelled using a one-dimensional transmission line analogy, and the rapidly flaring bell is modelled using a two-dimensional finite-difference method. The connection between the different regions is done by the aid of impedance boundary conditions. The use of such boundary conditions is investigated with respect to the required number of degrees of freedom. Numerical shape optimisation is employed in order to design horns with desired impedance characteristics throughout a design frequency band. A loudspeaker horn is optimised with respect to its sound power output, and a brass instrument is optimised with respect to its intonation. The horns are modelled using the finite-element method and a transmission line analogy. In order to achieve rapid convergence of the optimisation, gradient based minimisation algorithms are used. A prerequisite for success is the ability to accurately and inexpensively compute the gradient of the objective function. The gradient for the finite-element method is computed by an adjoint equation technique, whereas for the transmission line analogy, it is derived by formal differentiation of the model. In order to find smooth solutions, a smoothing technique is used, where optimisation is done with respect to the right hand side of a Poisson type equation.

Thesis (Ph.D.) -- University of Adelaide, Department of Mechanical Engineering, 1978.

Thesis (D. Mus. Arts)--University of Washington, 1998. / Vita. Includes bibliographical references (p. [179]-198).

Thesis (Ph. D.)--Lehigh University, 2005. / Includes vita. Includes bibliographical references (leaves 261-275).

Thesis (D.M.A.)--University of Texas at Austin, 2003. / Supervisor: Russell Pinkston. Vita. Includes bibliographical references. Available also from UMI Company.

Thesis (M.M.)--Ohio University, June, 2009. / Title from PDF t.p. Includes bibliographical references.

abstract: The C.G. Conn instrument manufacturing company is known as one of the most successful and innovative band instrument manufacturers in the history of the United States. Many of C.G. Conn's instrument product lines have undergone significant changes throughout the company's history, especially in the brass family. The C.G. Conn tuba product lines are no exception to this company's extraordinary success, and have been significantly redesigned since the company began manufacturing these instruments in circa 1880. This research project investigates the tuba product lines that C.G. Conn manufactured between 1880 and 1940. C.G. Conn designed six different tuba product lines during this timeframe, including an unnamed tuba product line with Stölzel valves, the Wonder Valve line, the New American line, the Wonder Model line, the 20-J, and the 22-J instrumental product lines. These tuba product lines have been investigated using extant publications and patent information because the majority of C.G. Conn's internal records prior to 1970 have been lost. In addition to investigating each of C.G. Conn's early tuba product lines, this project also explores the particularly anomalous design in the top-action valve apparatus of the Conn Wonder Model tuba product line. This anomalous design was implemented in the all of C.G. Conn's top-action tuba and tuba-like product lines from circa 1890-1940. This author's measurements of period instruments and analysis of data taken from these measurements indicates that this anomalous top-action valve apparatus design utilized interchangeable parts with other front-action C.G. Conn tuba product lines. / Dissertation/Thesis / Doctoral Dissertation Music 2014

abstract: Electro-acoustic compositions throughout the twentieth-century have flourished due to the modern advancements and improvements in technology, including image based interactive software. This project aims to reveal how three composers of different backgrounds utilize the use of euphonium in combination with live interactive electronics. To this date no known works have been composed for this instrumentation. Advancements in the development of audio software and hardware have helped to improve and rapidly evolve the inclusion of live electronics including the use of performer-triggered events, audio processing, and live electronic decision-making. These technologies can be utilized and explored in various ways. Three composers have been commissioned to each compose a new work focusing on using the timbre of the euphonium in combination with explored electronic sounds, unplanned sounds of nature and the use of the human voice. Each work is performed and examined by the author in order to further explore the electro-acoustic properties of this genre, how they communicate and interact with one another, and how the electronics interact and meld with the sound of the euphonium. Compositional elements in this project include but are not limited to the use of pre-recorded natural and “un-natural” sounds, and the manipulations of both pre-recorded and live sounds through the use of performer triggered events using visual programming languages such as Max/MSP and looping pedals. / Dissertation/Thesis / Zero Circle-Justin Rito (Live Recording) / Warrior-Brett Copeland (Live Recording) / Petrichor-Grant Jahn (Live Recording) / Doctoral Dissertation Music 2017

Este trabalho visou estudar o efeito dos parâmetros microestruturais da liga de latão 60/40 isenta de chumbo, com enfoque na observação da influência de 4 diferentes frações volumétricas e morfologias da fase &#946 nos aspectos de usinabilidade. Os resultados foram comparados com duas referências comerciais de ligas de latão, sendo uma de corte livre com adição de chumbo, e outra de latão 70/30 isenta de fase &#946. Esta comparação foi feita por meio dos ensaios de caracterização microestrutural, ensaios mecânicos de dureza Vickers, tração uniaxial e ensaios de usinabilidade. Na avaliação da usinabilidade foram estudadas as morfologias macro e microestrutural dos cavacos, rugosidade final das peças usinadas, medição das forças de corte e análise da vida útil da ferramenta. Esta comparação de desempenho em usinabilidade busca viabilizar a gradativa substituição das ligas de latão com chumbo por ligas isentas de metais pesados, preenchendo uma demanda crescente de mercado por este tipo de produto. A fase &#946 exerce uma importante influência na redução das forças de corte e rugosidade, além do fato de que o efeito térmico cumpre um papel importante no comportamento em usinagem dos latões, evidenciado pela alteração das frações volumétricas das fases µ e &#946 no cavaco analisado, a qual é associada a uma transformação de ordem-desordem. / This work presents a study of microstructural features of lead-free 60/40 brasses on their machinability, which was focused on the observation of four different volumetric fractions and morphologies of &#946 phase. Two commercial brasses were used as base materials: a free cutting brass with lead and a 70/30 brass without &#946 phase, respectively. These materials were manufactured through hot extruded, cold worked and heat treated rods of these three different alloys, and submitted a microstructure analysis, and mechanical characterization by Vickers hardness and a uniaxial tensile test. Machinability tests were conducted to evaluate the morphology and microstructure of the chips and the final roughness of the workpieces, cutting forces and tool wear test. The results help to evaluate the feasibility of substitution of the leaded brasses for brasses without heavy metals, filling a growing demand for this product in the industry. The &#946 phase has a strong influence on cutting forces and roughness reduction as well as the thermal effect plays an important role in the volume fraction of µ and &#946 phases of the analyzed chip, which was related to the presence of &#946 phase and an order-disorder transformation.