Thesis (M.Soc.Sc.)--University of Hong Kong, 1989. / Also available in print.

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This thesis draws a distinction between the nature of intonation and tuning in tonal and atonal music. I describe the musical aesthetic of the Second Viennese School as conditioned by and born out of equal temperament. In contrast, tonal music often employs intonation that varies from equal temperament significantly. These contrasting notions are explored through an examination of two historically opposed ideologies that concern consonance and dissonance. This thesis suggests that the aesthetic evaluation of twelve-tone atonal music may be informed by its theoretical limitation to the equally tempered scale. It is dissonance within discordance, referring to a preponderance of dissonant harmony within a dissonant medium of tuning. Supplementary audio files are included to support this thesis. Examples 1-9 compare various chords and progressions in just intonation and equal temperament. Example 10 is a midi version of "Yesterday I Heard the Rain," arranged by Brent Graham, in equal temperament.

The objective of this research is to design well-tuned, wideband elements for thin planar or cylindrically conformal arrays of balanced elements fed over ground. These arrays have closely spaced elements to achieve wide bandwidths through mutual coupling. This dissertation develops two wideband designs in infinite, semi-infinite, and finite array configurations. The infinite array is best for element tuning. This research advances a concept of a distributed, parallel capacitance between elements and across feeds that must be mutually altered for tuning. Semi-infinite techniques limit the problem space and determine the proper resistive loads to control the low-frequency array-guided surface wave (AGSW). The tight physical placement also forms a periodic structure that, along with the array boundary, launches a wave across the array surface. Options to suppress this surface wave are resistive loading and cylindrical conformations. AGSW control is necessary to achieve a maximum bandwidth, but lower radiation or aperture efficiency results. Conformation is shown to be an ineffective method for AGSW control alone. The Wrapped Bowtie design emerges as a novel design offering nearly a 10:1 bandwidth as a finite array over ground. Some bandwidth comes from the losses in radiation efficiency, which is necessary to control the AGSW; however, its simulated VSWR < 3 bandwidth in an infinite array is 7.24:1 with full efficiency. Less than perfect efficiency is required to mitigate surface wave effects, unless bandwidth is to be compromised. That loss may be as radiation or aperture efficiency, but it is unavoidable if the infinite array bandwidth is to be maintained in finite array designs. Lastly, this research articulates a development path for tightly-coupled arrays that extends in stages from infinite to semi-infinite, and thence finite layouts. Distinctions are explained and defended for the design focus at each stage. Element design, tuning, and initial feed design occur at the infinite array stage; AGSW suppression occurs at the semi-infinite stage; and design confirmation occurs only with the finite array. / Ph. D.

In this thesis, a Reinforcement Learning (RL) method called Sarsa is used to dynamically tune a PI-controller for a Continuous Stirred Tank Heater (CSTH) experimental setup. The proposed approach uses an approximate model to train the RL agent in the simulation environment before implementation on the real plant. This is done in order to help the RL agent initially start from a reasonably stable policy. Learning without any information about the dynamics of the process is not practically feasible due to the great amount of data (time) that the RL algorithm requires and safety issues. The process in this thesis is modeled with a First Order Plus Time Delay (FOPTD) transfer function, because almost all of the chemical processes can be sufficiently represented by this class of transfer functions. The presence of a delay term in this type of transfer functions makes them inherently more complicated models for RL methods. RL methods should be combined with generalization techniques to handle the continuous state space. Here, parameterized quadratic function approximation compounded with k-nearest neighborhood function approximation is used for the regions close and far from the origin, respectively. Applying each of these generalization methods separately has some disadvantages, hence their combination is used to overcome these flaws. The proposed RL-based PI-controller is initially trained in the simulation environment. Thereafter, the policy of the simulation-based RL agent is used as the starting policy of the RL agent during implementation on the experimental setup. As a result of the existing plant-model mismatch, the performance of the RL-based PI-controller using this primary policy is not as good as the simulationresults; however, training on the real plant results in a significant improvement in this performance. On the other hand, the IMC-tuned PI-controllers, which are the most commonly used feedback controllers are also compared and they also degrade because of the inevitable plant-model mismatch. To improve the performance of these IMC-tuned PI-controllers, re-tuning of these controllers based on a more precise model of the process is necessary. The experimental tests are carried out for the cases of set-point tracking and disturbance rejection. In both cases, the successful adaptability of the RL-based PI-controller is clearly evident. Finally, in the case of a disturbance entering the process, the performance of the proposed model-free self-tuning PI-controller degrades more, when compared to the existing IMC controllers. However, the adaptability of the RL-based PI- controller provides a good solution to this problem. After being trained to handle disturbances in the process, an improved control policy is obtained, which is able to successfully return the output to the set-point. / Process Control

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A new tuning scheme for linearly tunable high-Q filters is proposed. The tuning method is based on using the phase information for both frequency and Q factor tuning. There is no need to find out the relationship between a filter's passband magnitude and Q. A gm-C biquadratic filter is designed to demonstrate the proposed tuning circuitry. The project includes a phase locked loop (PLL) based frequency tuning loop, reference clock generator, and differential difference amplifier (DDA) for dealing with frequency and Q factor tuning loop and linearly tunable second order gm-C bandpass filter. Simulation results for a 10 MHz prototype filter using AMI 0.5μm process is presented. The chip testing results show that the automatic frequency tuning error is 2.5% for the 10 MHz case.

ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / A prototype wireless power transfer system using the near field to transfer energy between resonantly tuned coils, in order to charge a cell phone or other small electronic device. The system uses resonance to ensure maximum wireless power transfer efficiency between the two coils, and gain greater flexibility in distance between the two coils. The frequency of power transfer is in the unregulated 6.78MHz ISM band. The system is monitored and controlled by an Arduino, and shuts off power when the system does not detect a load.