The purpose of this thesis was to explore the behavior in power sharing and control of Hybrid Motor Drives. In this research, a solar-based hybrid adjustable-speed pump, which has been developed in the laboratory, was used to investigate the power-sharing in hybrid (dual-input) motor-drive systems. The laboratory test setup contained a DC-DC module connected to the DC-bus capacitors of a 2.5hp 230V PWM-based adjustable-speed motor-drive. The experimental results demonstrate that the power-sharing of a Photovoltaic (PV) array/DC-DC converter is not a function of motor speed in hybrid solar-based motor-drives, as long as the power contribution of the AC-grid stays above zero. In these conditions, the PV-DC-DC module behaves like a current source, and the dynamic behavior of the motor is decoupled from the dynamic behavior of the AC-grid, given that the PV-DC-DC module can provide the motor load.

Bright Sheng (b. 1955) has won international acclaim for successfully fusing disparate musical elements in his works. Listeners can trace Chinese pentatonic scales and instrumental effects mixed with Western classical structures. Postcards (1997) is a well-received orchestral work that successfully merges diverse musical styles and compositional techniques. Sheng based Postcards on material from his Four Movements for Piano Trio (1990). He applies masterful and distinctive orchestration to transform the chamber work into a multi-layered and colorful orchestral canvas. He fuses polyrhythm and post-tonal compositional techniques such as polytonality with Chinese musical elements, including folk song quotations, pentatonic scales and extended instrumental effects. The resulting hybrid is an outstanding artistic work that warrants further discussion and analysis for deeper understanding This study provides an overview of Sheng’s life experience and educational background in Chapter 1. Chapter 2 and 3 present a detailed analysis of the important compositional attributes and orchestration techniques Sheng applies in Postcards. Chapter 4 provides important performance considerations for conductors to enhance preparation. With an understanding of Sheng’s hybrid style, it is hoped that conductors will have a better interpretative grasp to lead an informed performance and scholars will have a better context for Sheng’s orchestral compositions.

Cyber security is quickly becoming one of the most important issues in the field of global politics. For this reason, it is vital to pay attention to topics in this field since they can impact international relations in a major way. Inspired by this, the thesis is focused on analysis, characterization, and categorization of cyber-attacks, which had been aimed at the Islamic Republic of Iran since 2007. The goal of the thesis is dual: to provide a complex picture of such incidents, and also to decide whether those attacks can be considered as evidence of hybrid warfare of some states against Iran. Data and reports about cyber-attacks were analyzed using AVOIDIT taxonomy in order to outline their basic characteristics. The characteristics were then contrasted with the definition of hybrid warfare. The final result of the analysis is that the cyber-attacks against Iran cannot be considered as hybrid warfare, because they do not meet the basic tenets of the concept of hybrid warfare. The aspiration of the thesis is to provide a clearer insight into the topic of cyber- attacks and global politics and can serve as a guide for future discussions since the topic of hybrid warfare has become very divisive.

Currently, when an individual needs a mobility device, they must settle for walkers and rollators which cater to some of their needs. For some, this is acceptable, but for others these ill-fitted devices pose a threat to their safety as they increase the frequency of falling while walking. For individuals with ataxia, this problem is further exacerbated as they do not possess the needed motor functions to coordinate their movement and appropriately control the device. This brings relevancy to the topic of customizing walkers for certain individuals to ensure their safety. The patient in this project suffers from multiple system atrophy cerebellar type (MSA-C), a rare progressive neurodegenerative disease which results in the shrinking of the portion of the brain directly above the spinal cord. The disease is typically characterized by a lack of coordinated muscle control which affects the individual’s speech, eye movement, gait, and limb co-ordination. As with other forms of ataxia, there is little to no research on devices designed to support individuals with such a disease. The goal of this project is to design a walker suitable for the patient as it has been found that his unique condition cannot be adequately supported by commercially available walkers. The ergonomic walker created is a modification of the U-step walker designed and manufactured by In-Step Mobility Products Corporation. This walker was chosen based on its stable base technology and braking system designed for individuals with limited motor functions. The device was further modified to include an emergency brake system, a sensitive control panel, and a seat tailored to the anthropometric data of the patient. The result was an ergonomic walker designed to ensure the safety of the patient while giving him the confidence to walk independently.

The aim of this thesis is to present a structural model for a wind turbine and its supporting pylon, to analyze and simulate attendant vibration phenomena and to suggest and simulate an appropriate control procedure. A wind turbine can be described as an elastic system consisting of distributed parameter, beam and rod type, elements coupled to a rotating lumped mass generator/turbine component at one end. We allow for both lateral and torsional movements of the beam. Solution methods for related vibration and control problems are suggested and analyzed. Results of computations for sample problems are presented. Applications of control of structural vibrations in wind energy units using proof mass type actuators as part of the tip mass are also analyzed. / Master of Science

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he primary objective of this study is to validate and/or identify issues for available numerical methods and turbulence models in OpenFOAM 2.0.0. Such a study will provide a guideline for users, will aid acceptance of OpenFOAM as one of the research solvers at institutions and also guide future multidisciplinary research using OpenFOAM. In addition, a problem of aerospace interest such as the flow features and vortex breakdown around a VFE-II model is obtained for SA, SST RANS and SA-DDES models and compared with DLR experiment. The available numerical methods such as time schemes, convection schemes, P-V couplings and turbulence models are tested as available for a fundamental case of a backward facing step for RANS and Hybrid RANSLES prediction of fully turbulent flow at a Reynolds number of 32000 and the OpenFOAM predictions are validated against experimental data by Driver et.al and compared with Fluent predictions.

The study revealed that the subsidy programs implemented in Malawi over the years have exposed many farmers to the advantages of using improved farm inputs. Almost 86 percent of the participants had a chance to grow hybrids in their farming career and out of that number 89 percent continues to grow them on a yearly basis and 76 percent indicated that hybrids have turned out to be their preferred variety. It has also revealed that complete removal of subsidy will result in the demand for inputs from subsidy eligible farmers to be removed from the market. This is based on the fact that only 5 percent of the participants were willing to pay for the improved input packages at market prevailing price.

The cost and fuel economy of hybrid electrical vehicles (HEVs) are significantly dependent on the power-train energy storage system (ESS). A series HEV with a minimal all-electric mode (AEM) permits minimizing the size and cost of the ESS. This manuscript, pursuing the minimal size tactic, introduces a bandwidth based methodology for designing an efficient ESS. First, for a mid-size reference vehicle, a parametric study is carried out over various minimal-size ESSs, both hybrid (HESS) and non-hybrid (ESS), for finding the highest fuel economy. The results show that a specific type of high power battery with 4.5 kWh capacity can be selected as the winning candidate to study for further minimization. In a second study, following the twin goals of maximizing Fuel Economy (FE) and improving consumer acceptance, a sports car class Series-HEV (SHEV) was considered as a potential application which requires even more ESS minimization. The challenge with this vehicle is to reduce the ESS size compared to 4.5 kWh, because the available space allocation is only one fourth of the allowed battery size in the mid-size study by volume. Therefore, an advanced bandwidth-based controller is developed that allows a hybridized Subaru BRZ model to be realized with a light ESS. The result allows a SHEV to be realized with 1.13 kWh ESS capacity. In a third study, the objective is to find optimum SHEV designs with minimal AEM assumption which cover the design space between the fuel economies in the mid-size car study and the sports car study. Maximizing FE while minimizing ESS cost is more aligned with customer acceptance in the current state of market. The techniques applied to manage the power flow between energy sources of the power-train significantly affect the results of this optimization. A Pareto Frontier, including ESS cost and FE, for a SHEV with limited AEM, is introduced using an advanced bandwidth-based control strategy teamed up with duty ratio control. This controller allows the series hybrid’s advantage of tightly managing engine efficiency to be extended to lighter ESS, as compared to the size of the ESS in available products in the market.

Understanding the signaling mechanisms that determine juvenile-to-mature transition and bud fate is vital for controlling tree reproduction. FD-like proteins also appear to be important for initiating reproductive development. In this study, phylogenetic analysis showed that three FD-like genes (FDL1, FDL2, and FDL3) are present in the poplar genome. FDL1 and FDL2 are products of a recent whole genome duplication event while FDL3 escaped such duplication. Yeast two-hybrid assays demonstrated that FT1 and FT2 proteins interact with FDL3 protein, but not with FDL1 or FDL2 protein. Analysis of the expression levels of FD-like transcripts in Populus deltoides via quantitative real-time PCR showed that FDL3 abundantly expresses in the shoot apex where it probably interacts with FT1 in late winter and early spring. Following the duplication event, FDL1 and FDL2 appear to have diverged in function as they express in a number of tissues in the fall, winter, and spring.