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Nanoporous gold is an exciting topic that has been highly researched due to its potential in applications including sensing, catalysts, gas storage, and heat exchangers, made possible by its high surface area to volume ratio and high porosity. However, these applications tend to require a specific morphology, which is often difficult to control. In this work, significant strides have been made in tuning the morphology of nanoporous gold by studying the effect of different fabrication parameters on the ligament diameter, pore diameter, and ligament length, three characteristics which are most discussed in previous studies concerning nanoporous gold. This material also, generally shows a brittle behavior despite it consisting of a normally ductile constituent element, limiting many commercial applications. There have been multiple simulated studies on the tensile mechanical properties and the fracture mode of this material, but limited experimental tensile testing research exists due to technical difficulty of conducting such experiments with small fragile samples. We examine the tensile mechanical behavior of nanoporous gold with ligament sizes ranging from 10 to 30 nm using in situ tensile testing under an environmental scanning electron microscope (ESEM). A specially designed tensile stage and sample holders are used to deform the sample inside the ESEM, allowing us to observing both the macro and microscopic structure changes. Our experimental results advance our understandings of how porous structure influence the mechanical properties of nanoporous gold, and they also serve to increase the accuracy of future simulation studies that will take this material a step towards commercial use by providing a thorough understanding of its structural mechanical limitations. / MS

It is the belief of many tuners that the best education for the young tuner is to do apprentice work in a piano factory where he must learn all the construction of the piano from the frame work of the case to the final setting of the tuning pins. It appears that most tuners are men now in the late forties to late fifties and were either factory-trained or apprentice-trained by an experienced tuner. The situation has changed and the apprenticeship method of training professional men such as lawyers and physicians has long since been discarded as a method of education. It is now the generally accepted plan to go to a college or university where such specialized training is given or offered under the direction and tutelage of specialists, and where students learn other essential subjects, the knowledge of which is necessary to the success of any educated man or woman.

The purpose of this study was to explore the ways tuning to A = 432 Hz affects emotional response, timbre, sound quality, character and tone compared to the standard tuning of A = 440 Hz, and whether or not it is humanly possible to discern a difference between these two. This was all done in an effort to evaluate claims that A = 432 Hz is superior to standard tuning in regards the previously mentioned factors. For this to be done, the history and development of tuning standards as well as intonation systems, presented alongside theories on the basic physics of sound, the effect of spectral manipulation on timbre and sound, and finally memory structures for remembering musical pitches. As a musician and composer, exploring new ways of creating emotion and controlling the effects of a composition, and dispelling potential misinformation is always a worthwhile pursuit. The study was performed by way of surveys where respondents were asked to listen to a composition in two versions, one in A = 440 Hz and the other in A = 432 Hz and then rate the perceived similarity between these two. They were then asked to give their answer regarding preference and associations of character and emotional response to each version. Results show that the claims of the A = 432 Hz proponents might not be as simple as portrayed, but rather a more complex series of relationships. There is support for the idea that the two tunings are unique enough for the average human to discern a difference between the two, and that some type of unique character is contained in each tuning.

In Scania’s single speed engines for industrial and marine use, the engine speed is controlled by a PI-controller. This controller is tuned independent of engine type and application. This brings certain disadvantages since the engines are used in a wide range of applications where the dynamics may differ. In this thesis, the possibility to tune the controller automatically for a specific engine installation has been investigated. The work shows that automatic tuning is possible. By performing an identification experiment on the engine, the parameters in a first order model describing the dynamics of the engine and the load aggregate are determined. The control parameters are then determined as functions of the model parameters. Measurements on a generator set show that the proposed method provides a controller which is able to follow changes in the reference value, and to compensate for load disturbances. / I Scania’s envarvsmotorer för industri- och marin-bruk regleras varvtalet av en PI-regulator. Denna regulator är inställd oberoende av motortyp och applikation. Detta medför vissa nackdelar då motorerna används i flera olika typer av applikationer där dynamiken kan variera. I detta arbete har det undersökts huruvida det är möjligt att automatiskt ställa in parametrarna i en PID-regulator för en enskild motorinstallation. Arbetet visar att automatisk inställning är möjlig. Genom att göra ett identifieringsexperiment på motorn bestäms parametrarna i en första ordningens modell som beskriver dynamiken för den aktuella konfigurationen av motor och belastande aggregat. Därefter bestäms regulatorparametrarna som funktion av modellparametrarna. Mätningar på ett generatoraggregat visar att man med hjälp av den föreslagna metoden erhåller en inställning av regulatorn som både klarar av att följa börvärdesförändringar och kompensera för laststörningar.

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[pt] O processo de combinação de ações de sintonia fina não possui nem uma formulação precisa, nem uma abordagem formal para solucioná-lo. É necessário definir o que combinar dentre as múltiplas ações existentes e, uma vez escolhidas, como compor de maneira que as restrições sejam verificadas. Trata-se de um problema complexo e relevante na área de bancos de dados, tanto para soluções manuais pelo DBA como automáticas, por meio de softwares especializados. Isto ocorre pois os diferentes tipos de ações de sintonia possuem estratégias distintas para alcançar o objetivo em comum. Esta tese propõe um método automático para geração e seleção de soluções combinadas de sintonia fina para bancos de dados relacionais. Discute-se como combinar soluções e respeitar as restrições tecnológicas e recursos computacionais disponíveis. Por fim, apresenta-se uma implementação e avaliação utilizando três SGBDs de mercado relevantes, em que mostramos tanto a eficácia como a eficiência do método proposto. Os resultados mostraram que o método é capaz de produzir soluções combinadas válidas mais eficientes que soluções locais independentes. / [en] The process of combining database tuning actions has neither a precise formulation nor a formal approach to solving it. It is necessary to define what to combine among multiple existing operations and, once chosen, how to compose so that constraints can be verified. It is a complex and relevant problem in the database research area, both for the DBA manual solutions, and automatic ones using specialized software. It is important because the different types of tuning actions have different strategies to achieve a common goal. This thesis proposes an automated method for generating and selecting combined tuning solutions for relational databases. It discusses how to mix solutions and still respect both the technological constraints and available computational resources. Finally, we present an implementation and evaluation using three relevant market DBMSs, where we show both the effectiveness and the efficiency of the proposed method. The results showed that the technique is capable of producing combined solutions that are more efficient than independent local solutions.