The passive devices used in the wireless communication system ¡]including resistor, capacitor and inductor¡^usually need high quality factor and low power dissipation characteristics. This thesis aims to develop a micro tunable capacitor with high-quality-factor and wide-tuning-range using surface micromachining. In contrast with conventional low-tuning-rate parallel-plate tunable capacitors, this research presents a concave structure and eight-suspending-beams layout design of the top electrode to enhance the elastic rigidity and tuning rate. In addition, this study appropriately decreases the thickness of top electrode, the tuning rate of such device can be improved to 65~2100%. On the other hand, in order to substantially increase quality factor, this thesis adopted the glass substrate ¡]Corning 7740¡^to reduce the power dissipation of high frequency operating signal. The optimized quality factor of this work is approximately equal to 41 under 2.4 GHz operation frequency. The material of sacrificial layer and top electrode adopted in this dissertation is aluminum and gold respectively. To avoid any breakage of the vertical supporting beams during releasing process, this research appropriately increases the width of vertical supporting beams, however, keep the thickness of the suspending part of top electrode for the maintenance of high quality factor and low driving voltage.

<p>In racing, it is useful to analyze vehicle performance and driving strategies to achieve the best result possible in competitions. This is often done by simulations and test driving.</p><p>In this thesis optimal control is used to examine how a racing car should be driven to minimize the lap time. This is achieved by calculating the optimal racing line at various tracks. The tracks can have arbitrary layout and consist of corners with non-constant radius. The road can have variable width. A four wheel vehicle model with lateral and longitudinal weight transfer is used.</p><p>To increase the performance of the optimization algorithm, a set of additional techniques are used. The most important one is to divide tracks into smaller overlapping segments and find the optimal line for each segment independently. This turned out to be useful when the track is long.</p><p>The optimal racing line is found for various tracks and cars. The solutions have several similarities to real driving techniques. The result is presented as driving instructions in Racer, a car simulator.</p>

Two age groups of infants were tested for their ability to learn an AAB or ABA repetition generalization in sequences of musical chords. The 4-month-olds, but not the 7.5-month-olds, successfully learned the generalization. Another group of 7.5-month-old infants successfully learned a generalization across melodies that all ended on a particular scale degree, even though the key of the melodies was varied. A survey of a musical corpus of children's songs reveals that AAB and ABA patterns do not occur more frequently than chance, while phrases frequently end on particular scale degrees. Together, these findings suggest that infants learn to constrain the set of generalizations they consider in order to favor those that rely upon features of the input that have proved reliable in their previous experience, specifically experience with a particular input domain. This raises the possibility that experience may play a significant role in parsing infants' environments into domains.

In racing, it is useful to analyze vehicle performance and driving strategies to achieve the best result possible in competitions. This is often done by simulations and test driving. In this thesis optimal control is used to examine how a racing car should be driven to minimize the lap time. This is achieved by calculating the optimal racing line at various tracks. The tracks can have arbitrary layout and consist of corners with non-constant radius. The road can have variable width. A four wheel vehicle model with lateral and longitudinal weight transfer is used. To increase the performance of the optimization algorithm, a set of additional techniques are used. The most important one is to divide tracks into smaller overlapping segments and find the optimal line for each segment independently. This turned out to be useful when the track is long. The optimal racing line is found for various tracks and cars. The solutions have several similarities to real driving techniques. The result is presented as driving instructions in Racer, a car simulator.

Over the last several decades we have witnessed tremendous change in the landscape of computer architecture. New architectures have emerged at a rapid pace with computing capabilities that have often exceeded our expectations. However, the rapid rate of architectural innovations has also been a source of major concern for the high-performance computing community. Each new architecture or even a new model of a given architecture has brought with it new features that have added to the complexity of the target platform. As a result, it has become increasingly difficult to exploit the full potential of modern architectures for complex scientific applications. The gap between the theoretical peak and the actual achievable performance has increased with every step of architectural innovation. As multi-core platforms become more pervasive, this performance gap is likely to increase. To deal with the changing nature of computer architecture and its ever increasing complexity, application developers laboriously retarget code, by hand, which often costs many person-months even for a single application. To address this problem, we developed a software-based strategy that can automatically tune applications to different architectures to deliver portable high-performance. This dissertation describes our automatic tuning strategy. Our strategy combines architecture-aware cost models with heuristic search to find the most suitable optimization parameters for the target platform. The key contribution of this work is a novel strategy for pruning the search space of transformation parameters. By focusing on architecture-dependent model parameters instead of transformation parameters themselves, we show that we can dramatically reduce the size of the search space and yet still achieve most of the benefits of the best tuning possible with exhaustive search. We present an evaluation of our strategy on a set of scientific applications and kernels on several different platforms. The experimental results presented in this dissertation suggest that our approach can produce significant performance improvement on a range of architectures at a cost that is not overly demanding.

Thesis submitted in compliance with the requirements for the Master's Degree in Technology: Electrical Engineering - Light Current, Durban University of Technology, Department of Electronic Engineering, 2008. / Linear control systems can be easily tuned using classical tuning techniques such as the Ziegler-Nichols and Cohen-Coon tuning formulae. Empirical studies have found that these conventional tuning methods result in an unsatisfactory control performance when they are used for processes experiencing the negative destabilizing effects of strong nonlinearities. It is for this reason that control practitioners often prefer to tune most nonlinear systems using trial and error tuning, or intuitive tuning. A need therefore exists for the development of a suitable tuning technique that is applicable for a wide range of control loops that do not respond satisfactorily to conventional tuning. Emerging technologies such as Swarm Intelligence (SI) have been utilized to solve many non-linear engineering problems. Particle Swarm Optimization (PSO), developed by Eberhart and Kennedy (1995), is a sub-field of SI and was inspired by swarming patterns occurring in nature such as flocking birds. It was observed that each individual exchanges previous experience, hence knowledge of the “best position” attained by an individual becomes globally known. In the study, the problem of identifying the PID controller parameters is considered as an optimization problem. An attempt has been made to determine the PID parameters employing the PSO technique. A wide range of typical process models commonly encountered in industry is used to assess the efficacy of the PSO methodology. Comparisons are made between the PSO technique and other conventional methods using simulations and real-time control.

Both behavioral and neurophysiological data indicate that many factors contribute to how infants tune to their native language(s) in early infancy. However, substantial debate remains regarding the neural mechanisms that underlie this tuning process. This study was designed to determine whether the behavioral changes in infants' processing of native and non-native speech during the second half of the first year correspond to qualitative neural processing changes that can be measured using near-infrared spectroscopy (NIRS). Specifically, we used NIRS to examine changes in hemodynamic activity in monolingually-exposed infants between the ages of 3 and 14 months while they were exposed to native (English) and non-native (Spanish) speech. In all infants, measurements were taken from the bilateral temporal regions of the cerebral cortex. Three age groups were tested: pre-tuned infants, who should show no sensitivity to phonological differences between the native and non-native speech samples (3-to-6-month-olds), actively tuning infants, who should be beginning to differentiate between the phonology of the native and non-native speech samples (7-to-10-month-olds), and tuned infants, who should readily distinguish between the phonologies of the native and non-native speech samples (11-to-14-month-olds). Results demonstrated significant differences in hemodynamic activity during the processing of native speech compared to non-native speech in each of the three age groups, with qualitatively different patterns of hemispheric lateralization emerging in response to the two types of speech in each of the three groups. These findings point to a potential neural marker of infants' sensitivity to the phonology of their native language as it emerges with increasing age that will be useful in future research.

Method books are an integral part of the percussion pedagogy. Because of the vast number of instruments a modern percussionist is expected to play, they often look for progressive, concise, and effective resources that can make learning such a variety of instruments more efficient. Instructional books currently exist for many areas of percussion performance, including snare drum, mallet percussion, timpani, World music, accessories, and marching percussion. Included in these books are information and procedures on music reading, rhythm studies, listening skills, part preparation, and technical approach. Focusing on timpani methods specifically, many of these books include tuning and pedaling exercises and etudes. However, their pedagogies for the execution of such difficult procedures are superficial and focus primarily on technical prowess. Timpani are the only Western pitched instruments a percussionist is required to tune, which proves intimidating for many players. Moreover, the aural and technical demands of the contemporary timpanist are ever-increasing with the technical demands found in modern composition. This dissertation will address the skills and techniques for tuning and pedaling timpani ignored by current method books and provide the timpanist with a process through a systematic set of etudes with audio accompaniment tracks. The goals of this method are to target the specific set of skills needed by the timpanist for accurate and effective timpani tuning in a modern ensemble setting.

The purpose of this study is to investigate the g-d-G-C scordatura tuning for the double bass. The study will survey the historical use, develop a theoretical rational, investigate the pedagogical implications, and explore the compositional opportunities of the scordatura tuning.Though there are many unanswered questions concerning the historical use of this tuning system, it is clear that the double bass has a long history of using scordatura tunings. The sympathetic/fifths tuning (g-d-G-C) was the basis of Violoncello Suite No. 5 by J. S. Bach, and there are three known later uses of it.After a brief history of temperament, the study concludes that this particular tuning greatly improves the resonance and intonation of the double bass. The placement of the g/G strings between the d and C strings strengthens the sonic output and vibrancy of the bass because of the close relationships between the natural harmonic series of each string. The proximity of the tuning to the upper part of the circle of fifths (C/G/D) is an additional benefit.Though the scordatura tuning creates more difficult technical challenges than the all-fourths tuning, this tuning system works well in orchestral, solo and jazz performance. The scordatura tuning is easily adapted to the bass guitar and offers many new opportunities for jazz improvisation. This tuning system is not particularly effective in popular commercial music venues.Since the 1960's new pedagogical approaches to sequence of instruction, concepts of position and approaches to fingerings have emerged. This new school of bass pedagogy suggests how a method could be developed for learning the scordatura tuning.Most of the traditional orchestral, ensemble, solo and jazz literature can be adapted to the tuning. Though it may be technically possible to play a work originally written for the all-fourths tuning using sympathetic/fifths, such a transcription may not be appropriate.Finally, the study includes four original compositions with analysis and discussion that demonstrate the idiomatic possibilities of the tuning: Sonata No. 5 for Scordatura Double Bass, Quartet No. 3B for Mixed Double Basses, Overture for Jazz Combo, and Concerto No. 3 for Scordatura Double Bass.Total Words of Abstract: 347 (does not include title) / School of Music

Multi-band and multi-mode radios are becoming prevalent and necessary in order to provide optimal data rates across a network with a diverse and spotty landscape of coverage areas (3G, HSPA, LTE, etc.). As the number of required bands and modes increases, the aggregate cost of discrete RF signal chains justi es the adoption of tunable solutions. Tunable fi lters are one of the pieces crucial to signal chain amalgamation. The main requirements for a tunable fi lter are high unloaded quality factor, wide tuning range, high tuning speed, high linearity, and small size. MEMS technology is the most promising in terms of tuning range, quality factor, linearity and size. In addition, a fi lter that maintains a constant passband bandwidth as the center frequency is tuned is preferred since the analog baseband processing circuitry tends to be tailored for a particular signal bandwidth. In this work, a novel design technique for tunable fi lters with controlled and predictable bandwidth variation is presented. The design technique is presented alongside an analysis and modeling method for predicting the final filter response during design optimization. The method is based on the well known coupling matrix model. In order to demonstrate the design and modeling technique, a novel coupling structure for stripline fi lters is presented that results in substantial improvements in coupling bandwidth variation over an octave tuning range when compared to combline and interdigitated coupled line fi lters. In order for a coupled resonator filter to produce an equal ripple Chebyshev response, each resonator of the fi lter must be tuned to precisely the same resonant frequency. Production tuned fi lters are routinely tuned in the lab and production environments by skilled technicians in order to compensate for manufacturing tolerances. However, integrated tunable filters cannot be tuned by traditional means since they are integrated into systems on circuit boards or inside front end modules. A fixed tuning table for all manufactured modules is inadequate since the required tuning accuracy exceeds the tolerance of the tuning elements. In this work, we develop tuning techniques for the automatic in-circuit tuning of tunable filters using scalar transmission measurement. The scalar transmission based techniques obviate the use of directional couplers. Techniques based on both swept and single frequency scalar transmission measurement are developed. The swept frequency technique, based on the Hilbert transform derived relative groupdelay, tunes both couplings and resonant frequencies while the single frequency technique only tunes the center frequency. High performance filters necessitate high resonator quality factors. Although fi lters are traditionally treated as passive devices, tunable fi lters need to be treated as active devices. Tuning elements invariably introduce non-linearities that limit the useful power handling of the tunable fi lter. RF MEMS devices have been a topic of intense research for many years for their promising characteristics of high quality factor and high power handling. Control and reliability issues have resulted in a shift from continuously tunable devices to discretely switched devices. However, fi lter tuning applications require fine resolution and therefore many bits for digital capacitor banks. An analog/digital hybrid tuning approach would enable the tuning range of a switched capacitor bank to be combined with the tuning resolution of an analog tunable capacitor. In this work, a device-level position control mechanism is proposed for piezoresistive feedback of device capacitance over the device's tuning range. It is shown that piezoresistve position control is ef ective at improving capacitance uncertainty in a CMOS integrated RF MEMS variable capacitor.