This corpus-based study investigates the most frequent occurring prepositional verbs collocated with the Japanese syntactic compound verb -kiru and aims to establish how the prepositional verb affects the semantic meaning of the verb-kiru construct. The study uses sketchengine’s online database, “Japanese Web2011”, which contains around 8 billion Japanese terms collected from the internet from various online sources from 2011 and onwards. From my results I was able to establish the most frequent occurring prepositional verbs in a -kiru construct from the database, and through a concordance analysis I was able to identify three semantic meanings incurred by the syntactic compound verb -kiru: the semantic meaning of completion, the dual semantic meaning of completion and extremity and the semantic meaning of extremity. Further analysis showed that the semantic meaning of extremity exists in the deep structure of the sentence and when transformed to the surface structure the semantic meaning shifts to that of completion.

Deep reinforcement learning algorithms typically require vast amounts of data to train to a useful level of performance. Each time new data is encountered, the network must inefficiently update all of its parameters. Auxiliary memory units can help deep neural networks train more efficiently by separating computation from storage, and providing a means to rapidly store and retrieve precise information. We present four deep reinforcement learning models augmented with external memory, and benchmark their performance on ten tasks from the Arcade Learning Environment. Our discussion and insights will be helpful for future RL researchers developing their own memory agents.

Now a days, the society thinks about more sustainable and clean energy sources. Most of the countries in the world relay on non-renewable energy sources for the generation of electricity. This results in the scarcity of fossil fuels in future and also increases the production of carbon emissions. This thesis considers a metro system named Kochi Metro which is a rapid transit system serving in the city of Kochi in Kerala, India which uses renewable sources, mainly solar, for giving power to the Metro.In this thesis work, trying to analyze the measures adopted by Kochi Metro Rail project in potential reductions of energy consumption and energy generation both contributing to energy efficiency.With the help of Matlab, different levels of installed PV power are used to find out the possible self-usage, self-sufficiency, and energy neutrality of the system.

In this document we report the synthesis, characterization, and utility of a chiral amidoacrylate substrate. This substrate features a reactive alkene that can be used in a variety of reactions. [3+2]-Cycloaddition reactions to form pyrroloindolines are shown to proceed with excellent diastereoselectivity (>20:1) and yield (86%). [3+2]-Reactions allow for the stereoselective construction of the pyrroloindoline backbone common in many natural products. Diels-Alder reactions catalyzed by TiCl4 show high yields (82%) with ~2:1 diastereoselectivity. Cyclopropanation reactions proceed in moderate yield (71%) and diastereoselectivity (~3:1). Both Diels-Alder and cyclopropanation reactions utilizing the chiral amidoacrylate substrate serve to stereoselectively produce unnatural amino acids which can serve as building blocks for natural products or aid in peptide stabilization. Further chiral Lewis acid catalyzed studies using an achiral amidoacrylate substrate are also explored.

In this thesis, integrated active filter auxiliary power modules (AFAPMs) is presented in electrified vehicle applications. A topological evaluation is conducted particularly for the auxiliary power module (APM) applications in the electrified vehicles. Several primary and secondary base topologies are compared in terms of VA rating and performance. Multiple input/output topology configurations are compared with different connection configurations and control schemes. The MOSFET loss analysis is given. Based on the MOSFET loss analysis, the modular full bridge current doubler with input-series-output-parallel configuration presents better performance in terms of the switch efficiency and cost analysis. Bulk capacitor banks occupy large volume and impact the reliability in the traction inverter and HV battery charger in the vehicle applications. A capacitor-less design is relatively urgent for the next generation electrified vehicle. Active filter (AF) is one potential solution to reduce the corresponding dc-link capacitance. However, additional components are required which increases the system complicity and decreases its reliability. Hence, it would be great to integrate the AF into the LV battery charger for the vehicle applications. Based on the power switch requirements, the AFAPM is evaluated for traction inverter and HV battery charger, respectively. The evaluation result shows that the AFAPM for the HV battery charger system is a feasible and attractive solution. Furthermore, a simple and effective dual-mode dual-voltage charging system operating principle is proposed. The integrated AFAPM converter charges the LV battery when the vehicle is running and operates as an AF when the vehicle is connected to the grid and the HV battery is charging. Hence, the low-frequency second-order harmonic current is alleviated without a bulk capacitor bank or an extra AF circuit in the HV battery charger. For magnetic design, there is a trend toward integration and planarization. Two planar transformers are built for two different AFAPM prototypes. A minimized leakage inductance method is presented and implemented on a 20:1 center-tapped planar transformer. Three different integrated AFAPM converters are proposed. By applying these AFAPM converters, the required extra components to form the AF for the HV battery charger are reduced and thus the cost, size and weight for the dual-voltage charging system in the electrified vehicle applications can be reduced. Two prototypes are built. The experiments show promising results confirming the effectiveness of the proposed converters. / Dissertation / Doctor of Philosophy (PhD)

No description available.

Due to the superior characteristics compared to its silicon (Si) counterpart, the wide bandgap (WBG) semiconductor enables next-generation power electronics systems with higher efficiency and higher power density. With higher blocking voltage available, WBG devices, especially the silicon carbide (SiC) metal-oxide-semiconductor field-effect transistor (MOSFET), have been widely explored in various medium-voltage (MV) applications in both industry and academia. However, due to the high di/dt and high dv/dt during the switching transient, potential overcurrent, overvoltage, and gate failure can greatly reduce the reliability of implementing SiC MOSFETs in an MV system. By utilizing the parasitic inductance between the Kelvin- and the power-source terminal, a short-circuit (SC) and overload (OL) dual-protection scheme is proposed for overcurrent protection. A full design procedure and reliability analysis are given for SC circuit design. A novel OL circuit is proposed to protect OL faults at the gate-driver level. The protection procedure can detect an SC fault within 50 nanoseconds and protect the device within 1.1 microsecond. The proposed method is a simple and effective solution for the potential overcurrent problem of the SiC MOSFET. For SiC MOSFETs in series-connection, the unbalanced voltages can result in system failure due to device breakdown or unbalanced thermal stresses. By injecting current during the turn-off transient, an active dv/dt control method is used for voltage balancing. A 6 kV phase-leg using eight 1.7 kV SiC MOSFETs in series-connection has been tested with voltage balanced accurately. Modeling of the stacked SiC MOSFET with active dv/dt control is also done to summarize the design methodology for an effective and stable system. This method provides a low-loss and compact solution for overvoltage problems when MV SiC MOSFETs are connected in series. Furthermore, a scalable auxiliary power network is proposed to prevent gate failure caused by unstable gate voltage or EMI interference. The two-stage auxiliary power network (APN) architecture includes a wireless power transfer (WPT) converter supplied by a grounded low voltage dc bus, a high step-down-ratio (HSD) converter powered from dc-link capacitors, and a battery-based mini-UPS backup power supply. The auxiliary-power-only pre-charge and discharge circuits are also designed for a 6 kV power electronics building block (PEBB). The proposed architecture provides a general solution of a scalable and reliable auxiliary power network for the SiC-MOSFET-based MV converter. For the WPT converter, a multi-objective optimization on efficiency, EMI mitigation, and high voltage insulation capability have been proposed. Specifically, a series-series-CL topology is proposed for the WPT converter. With the optimization and new topology, a 120 W, 48 V to 48 V WPT converter has been tested to be a reliable part of the auxiliary power network. For the HSD converter, a novel unidirectional voltage-balancing circuit is proposed and connected in an interleaved manner, which provides a fully modular and scalable solution. A ``linear regulator + buck" solution is proposed to be an integrated on-board auxiliary power supply. A 6 kV to 45 V, 100 W converter prototype is built and tested to be another critical part of the auxiliary power network. / Doctor of Philosophy / The wide bandgap semiconductor enables next-generation power electronics systems with higher efficiency and higher power density which will reduce the space, weight, and cost for power supply and conversion systems, especially for renewable energy. However, by pushing the system voltage level higher to medium-voltage of tens of kilovolts, although the system has higher efficiency and simpler control, the reliability drops. This dissertation, therefore, focusing on solving the possible overcurrent, overvoltage, and gate failure issues of the power electronics system that is caused by the high voltage and high electromagnetic interference environment. By utilizing the inductance of the device, a dual-protection method is proposed to prevent the overcurrent problem. The overcurrent fault can be detected within tens of nanoseconds so that the device will not be destroyed because of the huge fault current. When multiple devices are connected in series to hold higher voltage, the voltage sharing between different devices becomes another issue. The proposed modeling and control method for series-connected devices can balance the shared voltage, and make the control system stable so that no overvoltage problem will happen due to the non-evenly distributed voltages. Besides the possible overcurrent and overvoltage problems, losing control of the devices due to the unreliable auxiliary power supply is another issue. This dissertation proposed a scalable auxiliary power network with high efficiency, high immunity to electromagnetic interference, and high reliability. In this network, a wireless power transfer converter is designed to provide enough insulation and isolation capability, while a switched capacitor converter is designed to transfer voltage from several kilovolts to tens of volts. With the proposed overcurrent protection method, voltage sharing control, and reliable auxiliary power network, systems utilizing medium-voltage wide-bandgap semiconductor will have higher reliability to be implemented for different applications.

Single phase switched reluctance machines (SRMs) have a special place in the emerging high-volume, low-cost and low-performance applications in appliances and also in high-speed low-power motor drives in various industrial applications. Single phase SRMs have a number of drawbacks: low power density as they have only 50% utilization of windings, lack of self-starting feature unless otherwise built in to the machine, most of the times with permanent magnets or sometimes with distinct and special machine rotor configurations or additional mechanisms. Many of these approaches are expensive or make the manufacturing process more difficult. In order to overcome such disadvantages a method involving interpoles and windings is discussed in this research. Also, a new and novel converter topology requiring only a single switch and a single diode is realized. This research tests the concepts and feasibility of this new single-phase SRM motor topology and converter in one quadrant operation. The converter electronics and a simple minimum component, minimum cost analog converter are designed and implemented. The entire system is simulated and evaluated on its advantages and disadvantages. Simple testing without load is performed. This system has a large number of possibilities for development. Due to its lightweight, compact design and efficient, variable high-speed operation, the system might find many applications in pumps, fans, and drills. / Master of Science

History teaches us that novel materials, such as chlorofluorocarbon and asbestos, can have dire unintended consequences to human and environmental health. The exponential growth of the field of nanotechnology and the products developed along the way provide the opportunity for a new paradigm of design thinking, in which human and environmental impacts are considered early on in product development. In particular, nanocellulose is touted as a promising green nanomaterial, as it is sourced from an effectively inexhaustible feedstock of wood-based cellulose and is assumed to be harmless to the environment since it is derived from a natural material and assumed to be biodegradable. The various forms of nanocellulose possess an impressive diversity of properties, making it suitable for a wide variety of applications such as drug delivery, reinforcement, food additives, and iridescent make-up. However, as nanomaterials can have different properties relative to their bulk form, it is questionable whether they are truly environmentally friendly, particularly in terms of their biodegradability and potential impacts to receiving environments. Given the projected mass-scale application of nanocellulose and the inevitability of its subsequent release into environment, the purpose of this study was to determine the biodegradability of nanocellulose and the response of environmentally-relevant microbial communities. Specifically, it was hypothesized that cellulose in the nano size range would display distinct biodegradation patterns and rates, relative to larger forms of cellulose. Further, it was hypothesized that modification of nanocellulose, in terms of morphology and surface properties (e.g., charge), would further influence its biodegradability. Wetlands and anaerobic digesters were selected as two environmentally-relevant receiving environments that also play critical roles in global carbon turnover. To examine the biodegradability of nanocellulose, two distinct microbial consortia were enriched from wetland (W) and anaerobic digester (AD) inocula and applied in parallel experiments. The consortia were grown under anaerobic conditions with microcrystalline cellulose as the sole carbon substrate over a period of 246 days before being aliquoted to microcosms for subsequent biodegradation assays. Various forms of nanocellulose were spiked into the microcosms and compared with microcrystalline cellulose as a non nano reference. Microcosms were sacrificed in triplicate with time to monitor cellulose degradation as well as various measures of microbial community response. Microbial communities were characterized in terms of gene markers for total bacteria (16S rRNA genes) and anaerobic cellulose degraders (glycoside hydrolase family 48 genes, i.e., cel48) as well as high throughput amplicon sequencing of 16S rRNA genes (V4 region). A series of three studies examined: 1) the effect of nanocrystalline versus microcrystalline cellulose; 2) the effects of nanocellulose morphology (crystalline rod versus filament) and surface functionalization (cationic and anionic); and 3) metagenomic characterization of cellulose degrading communities using next-generation DNA sequencing. It was found that the nano- size range did not hinder cellulose degradation, in fact, nanocrystalline cellulose degraded slightly faster than microcrystalline cellulose according to 1st order kinetics (1st order decay constants: 0.62±0.08 wk-1 for anionic nanocrystalline cellulose versus 0.39±0.05 wk-1 for microcrystalline cellulose exposed to AD culture; 0.69±0.04 wk-1 for anionic nanocrystalline cellulose versus 0.58±0.05 wk-1 for microcrystalline cellulose exposed to W). Experiments comparing the effects of surface functionalization indicated that anionic nanocellulose degraded faster than cationic cellulose (1st order decay constants for cationic nanocrystalline cellulose: 0.48±0.06 wk-1 and 0.58±0.07 wk-1 on exposure to AD and W cultures respectively). Measurements of 16S rRNA and cel48 genes were consistent with this trend of greater biological growth and cellulose-degrading potential in the anionic nanocellulose condition, suggesting that surface properties can influence biodegradation patterns. Taxonomic characterization of 16S rRNA gene amplicons suggested that taxa known to contain anaerobic cellulose degraders were enriched in both W and AD consortia, which shifted in a distinct manner in response to exposure to the different cellulosic materials. This suggests that distinct groups of microbes may drive the biodegradation of different forms of cellulose. Further, metagenomic investigation provided new insight into taxonomic and functional aspects of anaerobic cellulose degradation, including identification of enzymatic families associated with degradation of the various forms of cellulose. Overall, the findings of this study advance understanding of anaerobic cellulose degradation and indicate that nanocellulose is likely to readily degrade in receiving environments and not pose an environmental concern. / Ph. D.

The once through steam generator (OTSG) is a single pass counter flow heat exchanger in which primary pressurized water from the core is circulated. Main Feedwater is injected in an annular gap on the outer periphery of the steam generator shroud such that it aspirates steam to preheat the feedwater to saturation temperature. An important component of the OTSG and enhanced once through steam generator (EOTSG) is the auxiliary feedwater system (AFW), which is used during accident/transient scenarios to remove residual heat by injecting water through jets along the outer periphery of the heat exchanger core directly on to the tubes at the top of the OTSG. The intention is for the injected water, which is subcooled, to spread into the tube nest and wet as many tubes as possible. In this project, the main objectives were to use first principles Computational Fluid Dynamics to predict the number of wetted tubes versus flow rate in the EOTSG at the AFW injection location above the top tube support plate. To perform the fluid analysis, the losses in the bypass leakage flow and broached hole leakage flow were first quantified and then used to model a 1/8th sector of the EOTSG. Using user defined functions (UDF), the loss coefficients of the leakage flows were implemented on the 1/8th sector of the EOTSG computational model to provide boundary conditions at the bypass flow and leakage flow locations With this method, the number of tubes wetted in the sector of EOTSG for various AFW flow rates was found. Results showed that the number of wetted tubes was in very close agreement to that predicted by experimental-analytical methods by the sponsor, AREVA. With the maximum flow rate of 65 l/s a total of 318 tubes were wetted and the percentage of tubes wetted with broached holes was 8.7%. The analysis on the bypass leakage flow showed that the loss coefficients was a function of the mass flow rate or the flow Reynolds number through the gap and it increased as the Reynolds number increased from 300 to 1600. The experimental and computational loss coefficients agree to within 15% of each other. In contrast, the constant loss coefficient of 1.3 used by AREVA was much higher than that obtained in this study, particularly in the low Reynolds number range. As the Reynolds number approached 3000, the loss coefficients from this study approached the value of 1.3. This value of the loss coefficient was implemented for the bypass flow leakage in the 1/8th sector of the EOTSG model. The analysis on the broached hole leakage flow was performed using a single hole, five holes, and one, two, four and eight rows of broached holes in order to characterize the loss coefficients. The one hole and five hole computational models were validated with experiments. The computational models showed the presence of voids in the leakage flow through the tube support plate (TSP), which were not observed (visually) in the experiments. The characterization of the broached hole leakage in the one, two and four rows showed that the loss coefficient of the control broached hole increased as the number of rows increased. These results indicated that for the same height of water on the TSP, the resistance to leakage flow increased as the number of tubes increased. They also indicated that leakage flow through the broached holes was not solely a function of the height of water above the TSP but also the surrounding geometrical topology and the flow characteristics. However, the analysis done for eight rows showed that the loss coefficient became constant after a certain number of rows as the loss coefficient differed by only 5% from the results of the four rows. From these results it was determined that the loss coefficient asymptotes to an estimated value of 4.0 which was implemented in the broached hole leakage flow in the 1/8th sector of the EOTSG. Computational models of the 1/8th sector of the EOTSG were implemented with the respective loss coefficients for the bypass and leakage flows. Results showed that as the AFW flow rate increased, the percentage wetted tubes increased. The data matched closely with AREVA's experimental-analytical model for flow rates of 14.5 l/s and higher. It was also deduced that complete wetting of the tubes is not possible at the maximum AFW flow rate of 65 l/s. / Master of Science