Descartes’ Compendium musicae and Lamy’s La Rhétorique ou l’art de parler, both published in English translation in London in the late seventeenth century, suggest approaches to period performance practice that support expressive intonation as a rhetorical device. Descartes’ unique perspective on musical pitch and intervals provides a methodology for understanding inflected intonation in performance. Closely aligned with Descartes’ epistemological perspective, Lamy’s treatise provides an understanding of expressive intention as essential to effective rhetorical delivery. These approaches are applied to musical examples from trio sonatas of Arcangelo Corelli, John Ravenscroft and Henry Purcell, demonstrating that expressive intonation using subtle pitch inflection can be explained as a rhetorical practice. These subtle pitch inflections, related as they are to both rhetorical delivery and intonation systems, are not reflected in notation but realized only as music is heard in time. It is in performance contexts that pitch inflection can be realized as an expressive device. A supplemental audio file contains five short examples demonstrating pitch deviation applied to selected intervals.

The generation of wind energy deliberately becomes a significant part of generated electrical power in developed nations. Factors like fluctuation in natural wind speed and the use of power electronics present issues related power quality in wind turbine application. Following to the fact that there have been remarkable increase of wind energy in the electrical energy production worldwide, the effect on power quality and power system stability caused by wind power is considered significant, and hence the evaluation of this effect is crucial and obligatory. In order to examine and evaluate the characteristics of power quality of grid-integration of wind power in a persistent and authentic manner, several guidelines were introduced and established. One of the widely used guideline to define power quality of wind turbine is IEC standard 61400-21. Moreover, power system operator demands wind turbines to tolerate a certain voltage dip in some countries. The wind turbines concepts such as doubly-fed induction generator wind turbine and the direct driven wind turbine wind turbine with a permanent magnet synchronous generator are considered as the most promising concepts among other wind turbine types since they can operate in wide range of wind speed. The major goal of this PhD work is to examine the power quality character aspects of these wind turbine concepts. The power quality problems were calculated according to that devised by IEC- 61400-21 and then compared afterwards. The research includes the evaluation of the following power quality characteristics: voltage dip response, current harmonics distortion, control of active and reactive power and voltage flicker. Besides the IEC-standard 61400-21, the study also looks into the short-circuit current and fault-ride through with specifications provided by some grid codes, as power system stability is greatly influenced by these aspects. In order to achieve the research's goal, a reliable dynamic model of wind turbine system and control are required. Thus a complete model for both wind turbines systems was developed in PSCAD/EMTDC simulation-program which is the fanatical power system analysis tool, which can achieve a complete simulation of the system dynamic behaviour from the wind turbine. Two controllers are adopted for wind turbine system, converter control and pitch angle control. The converter controlled by a vector control in order to regulate the active and the reactive power whereas the pitch control scheme is put to function to limit the aerodynamic power in high wind speed. The ability of providing adequate state steady and dynamic performances are what wind turbine assures, as examined by simulation results, and via this, problems related to power quality caused by integrating wind turbines to the grid can be studied by wind turbine model.

O desenvolvimento de aplicações de forma a atingir níveis de desempenho próximos aos níveis teóricos de uma determinada plataforma é uma tarefa que exige conhecimento técnico do ambiente de hardware, uma vez que o software deve explorar detalhes específicos da plataforma em questão. Pelo fato do software ser específico à plataforma, caso ela evolua ou se altere, as otimizações realizadas podem não explorar a nova arquitetura de forma eficiente. Auto-tuners são sistemas que surgiram como um meio automatizado de adaptar um determinado software a uma arquitetura alvo. Essa adaptação ocorre através de uma busca empírica de valores ótimos para parâmetros específicos de uma aplicação, a fim de ajustá-los às características do hardware, ou ainda através da geração de códigofonte otimizado para a plataforma. Este trabalho propõe um módulo auto-tuner orientado à adaptação parametrizada de uma aplicação paralela, que trabalha variando os fatores da dimensão do domínio bidimensional, o número de processos e a extensão das regiões de sobreposição. Para cada variação dos fatores, o auto-tuner testa a aplicação na arquitetura paralela de forma a buscar a combinação de parâmetros com melhor desempenho. Para possibilitar o auto-tuning, foi desenvolvida uma classe em linguagem C++ denominada Mesh, baseada no padrão MPI. A classe busca abstrair a decomposição de domínios de uma aplicação paralela por meio do uso de Orientação a Objetos, e facilita a variação da extensão das regiões de sobreposição entre os subdomínios. Os resultados experimentais demonstraram que o auto-tuner explora o ganho de desempenho pela variação do número de processos da aplicação, que também é tratado pelo módulo auto-tuner. A arquitetura paralela utilizada na validação não se mostrou ideal para uma otimização através do aumento da extensão das regiões sobrepostas entre subdomínios. / Achieving the peak performance level of a particular platform requires technical knowledge of the hardware environment involved, since the software must explore specific details inherent to the hardware. Once the software is optimized for a target platform, if the hardware evolves or is changed, the software probably would not be as efficient in the new environment. This performance portability problem is addressed by software auto-tuning, which emerged in the past decade as an automated technique to adapt a particular software to an underlying hardware. The software adaptation is performed by an auto-tuner. The auto-tuner is an entity that empirically adjusts specific application parameters in order to improve the overall application performance, or even generates source-code optimized for the target platform. This dissertation proposes an auto-tuner to optimize the domain decomposition of a parallel application that performs stencil computations. The proposed auto-tuner works in a parameterized adaptation fashion, and varies the dimensions of a 2D domain, the number of parallel processes and the extension of the overlapping zones between subdomains. For each combination of parameter values, the auto-tuner probes the application in the parallel architecture in order to seek the best combination of values. In order to make auto-tuning possible, it is proposed a C++ class called Mesh, based on the Message Passing Interface (MPI) standard. The role of this class is to abstract the domain decomposition from the application using the Object Orientation facilities provided by C++, and also to enable the extension of the overlapping zones between subdomain. The experimental results showed that the performance gains were mainly due to the variation of the number of processes, which was one of the application factors dealt by the auto-tuner. The parallel architecture used in the experiments showed itself as not adequate for optimizing the domain decomposition by increasing the overlapping zones extension.

Due to the recent rapid growth in personal mobile communication devices (smartphones, PDA's, tablets, etc.), the wireless market is always looking for new ways to further miniaturize the RF front-ends while reducing the cost and power consumption. For many years, wireless transceivers and subsystems have been relying on high quality factor (Q) passives (e.g., quartz crystal, ceramics) to implement oscillators, filters, and other key RF front-end circuitry elements. However, these off-chip discrete components occupy large chip area and require power-demanding interfacing circuits. As a result, a great deal of research effort has been devoted to the development of micromechanical resonators that are much more amenable to direct integration with integrated circuit (IC). Over the past few years, vibrating RF MEMS (Micro-Electrical-Mechanical-System) resonator technology has emerged as a viable solution, most notably, the film bulk acoustic resonator (FBAR) and surface acoustic wave (SAW) resonator, which have already been successfully implemented into commercial products. Undoubtedly, micromechanical resonators such as FBAR's can perform as well as if not better than its bulky conventional counterparts and facilitate the miniaturization and power reduction of conventional RF systems. However, in some cases when multi-frequency functionality on a single-chip is needed, FBAR simply won't deliver. To address this dilemma, contour-mode MEMS resonators have been developed and regarded as the most viable on-chip high-Q alternative. Unlike FBAR, contour-mode resonators use lateral dimensions to define its resonating frequencies, thus allowing for single-chip multi-frequency functionality. However, there is still room for improvement with respect to lowering the motional resistance of these devices to allow matching to 50 Ω electronics, while retaining low power consumption, small size, and simpler manufacturing process. This dissertation presents the design, fabrication, characterization and experimental analysis of two types of micro-mechanical resonators. Piezoelectrically- and electrostatically-transduced micromechanical resonators will both be shown. Both types of resonator will be fabricated in the same micro-fabrication run, which makes the comparison between the two much more impartial. The impacts of substrate's resistivity over the device performances will also be studied. Among the most significant results, this dissertation also presents several ideas that are enabled by the use of silicon-on-insulator (SOI) wafer. A novel single-mask fabrication process that can produce capacitive resonator with nano-meter gap is demonstrated. The concept of dual-transduced micro-mechanical resonator is introduced by combining both piezoelectric and capacitive based resonators. Finally, frequency tuning of MEMS resonator are explored and detailed in this work as well.

<p>This is a thesis report done as part of the Master of Science in Electronics Design Engineering given at Linköping University, Campus Norrköping. The thesis work is done at Ericsson AB in the spring of 2005. The thesis describes a method of removing variations in the tuning sensitivity of voltage-controlled crystal oscillators due to different manufacturing processes. These variations results in unwanted variations in the modulation bandwidth of the phase-locked loop the oscillator is used in. Through examination of the theory of phase-locked loops it is found that the bandwidth of the loop is dependent on the tuning sensitivity of the oscillator.</p><p>A method of correcting the oscillator-sensitivity by amplifying or attenuating the control-voltage of the oscillator is developed. The size of the correction depends on the difference in oscillator-sensitivity compared to that of an ideal oscillator. This error is measured and the correct correction constant calculated.</p><p>To facilitate the measurements and correction extra circuits are developed and inserted in the loop. The circuits are both analog and digital. The analog circuits are mounted on an extra circuit board and the digital circuits are implemented in VHDL in an external FPGA.</p><p>Tests and theoretical calculations show that the method is valid and able to correct both positive and negative variations in oscillator-sensitivity of up to a factor ±2.5 times. The bandwidth of the loop can be adjusted between 2 to 15 Hz (up to ±8 dB, relative an unmodified loop).</p>

Despite the vast amount of delivered theoretical results, regarding the topic of controller design, more than 90% of the controllers used in industry (petro-chemical, pulp and paper, steel, mining, etc) are of PID type (P, PI, PII, PD). This shows the importance of progressing in the elaboration of methods that consider restricted complexity controllers for practical applications, and that are computationally simple. Iterative Feedback Tuning (IFT) stands out as a new solution that takes into account both constraints. It belongs to the family of model-free controller tuning methods. It was developed at Cesame in the nineties and, since then, many real applications of IFT have been reported. This algorithm minimizes a cost function by means of a stochastic gradient descent scheme. In spite of the fact that the method has had an unexpected success in the tuning of real processes, a number of issues had not been fully covered yet. This thesis focuses on two aspects of this set of uncovered theoretical points: the convergence rate of the algorithm and a robust estimation of its gradient. Optimal prefilters, left as a degree of freedom for the user in the first formulation of IFT, are computed at each experiment. Their application allows a reduction in the covariance of the gradient estimate. Depending on what particular aspect the user is interested in improving, one optimal prefilter is selected. Monte-Carlo simulations have shown an enhancement with regards to a constant prefilter. A flexible arm set-up mounted in our robotics laboratory is used as a test bed to compare a model-based controller design algorithm with a model-free controller tuning method. The comparison is performed with some specifications defined beforehand. The same set-up plus a couple of air-jets serves as a tester for our theoretical results, when the rejection of a perturbation is the ultimate objective. Both cases have confirmed the predicted good behaviour offered by IFT.

The purpose of this study was to test a hypothesized model of wind-band intonation, using equipment, instruction and director and student attributes as components. Band directors (N= 5) and their students N= 200) were given a combination of published and researcher designed tests to measure equipment quality, experience, knowledge of instrument pitch tendencies and aural discrimination skills. In addition, each band was video recorded to observe their warm-up, tuning and rehearsal procedures and activities. Spectrum analysis using Praat phonetic analysis software (Boersma & Weenik, 2010) was used to measure wind-band intonation. Structural equation modeling (SEM) using AMOS (Arbuckle, 2008) was the method chosen to analyze and interpret the data. Although the hypothesized model could not be estimated, a model generating approach resulted in a three-factor model describing the effects of instruction and student attributes on wind-band intonation. Model fit was good (χ2 = 3.486, df = 7, p = .837, GFI = .994, CFI = 1.00, RMSEA = .000). The respecified model indicated that instruction and student attributes explain 99.3% of the variance in the dependent variable wind-band intonation. For each SD increase in the latent instruction variable, wind-band intonation increases by .95 a SD. Activities involving aural-based tuning strategies, tuning intervals and chords evidenced higher intonation scores. For each SD increase in the latent student attributes variable, wind-band intonation increases by .16 a SD. This suggests that instrument quality, experience in band and private lessons, and aural acuity combine to affect intonation scores, but these student attributes are less influential than instruction. A supplementary finding revealed that 72.5% of the students n = 145) made at least one error (M = 4.05, SD = 3.76) on the test measuring knowledge of their instrument’s pitch tendencies.

Thesis (D.M.E.)--Indiana University, 2006. / Computer printout. Includes bibliographical references (leaves 127-133) and abstract.

<p>Since the Renaissance, the normative approach to a philosophy of music has concerned itself primarily with the subjective experience of the listener. This was not always the case. From Greek Antiquity to the Renaissance, music was considered a rigorous, mathematical discipline that shed light on objective truths concerning cosmology and cosmogony. <i>Musica theorica</i>, therefore, took precedence over musica practica and was taken much more seiously in musical scholarship. Although tension had always existed between <i>Musica theorica</i> and <i>Musica practica</i>, such tension reached its peak during the Renaissance and as a result, a shift occurred: <i>Musica theorica</i> was pushed into the background, and <i>Musica practica</i> stepped forward.</p><p>The intention of this thesis is to convince its reader of the need to bring <i>Musica theorica</i> back to its proper place in musical and philosphical scholarship, where objective answers can be found, and music's innate eternal nature is revealed. The thesis begins with a historical survey of musical scholarship that eventually brings the reader to the center of the controversy that ensued during the Renaissance, and then forward to present day discussions in philosphy of music that are concerned with music's subjective and temporal properties. It is hoped that the reader will see the need for a new shift to occur in philosophy of music that focuses on music's objective and eternal properies (that are wholly distinct from the subject experiencing it), and will come away with a new perspective regarding the interdisciplinary nature of philosphy and music.

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