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The master’s thesis deals with modelling of various architectures of hybrid powertrains for three vehicle sizes in GT-SUITE and compares them in daily commuting operating mode. On top of making of the hybrid vehicle simulation models, control algorithms had to be created to manage the energy split between the internal combustion engine and the electric motor for each of the architectures. Routes to work and back were logged using the GPS and postprocessed to obtain the speed and the road grade profiles. Resulting data was used as an input in simulations of daily commuting. To compare all hybrid powertrain architectures, fuel economy and electricity consumption were evaluated for WLTP and daily commuting operating modes. Finally, the environmental impact of each topology was assessed based on an estimation of corresponding well-to-wheel emissions.

Increasing debates over a gasoline independent future and the reduction of greenhouse gas (GHG) emissions has led to a surge in plug-in hybrid electric vehicles (PHEVs) being developed around the world. Due to the limited all-electric range of PHEVs, a daytime PHEV charging infrastructure will be required for most PHEVs’ daily usage. This dissertation, for the first time, presents a mixed integer mathematical programming model to solve the PHEV charging infrastructure planning (PCIP) problem. Our case study, based on the Oak Ridge National Laboratory (ORNL) campus, produced encouraging results, indicates the viability of the modeling approach and substantiates the importance of considering both employee convenience and appropriate grid connections in the PCIP problem. Unfortunately, the classical optimization methods do not scale up well to larger practical problems. In order to effectively and efficiently attack larger PCIP problems, we develop a new MASTS based TS algorithm, PCIP-TS to solve the PCIP. The results from computational experiments for the ORNL campus problem establish the dominant supremacy of the PCIP-TS method both in terms of solution quality and computational time. Additional experiments with simulated data representative of a problem that might be faced by a small city show that PCIP-TS outperforms CPLEX based optimization. Once the charging infrastructure is in place, the immediate problem is to judiciously manage this system on a daily basis. This thesis formally develops a mixed integer linear program to solve the daily the energy management problem (DEM) faced by an organization and presented results of a case study performed for ORNL campus. The results from our case study, based on the Oak Ridge National Laboratory (ORNL) campus, are encouraging and substantiate the importance of controlled PHEV fleet charging and realizing V2G capabilities as opposed to uncontrolled charging methods. Although optimal solutions are obtained, the solver requires practically unacceptable computational times for larger problems. Hence, we develop a new MASTS based TS algorithm, DEM-TS, for the DEM models. Results for ORNL campus data set prove the dominant computational efficiency of the DEM-TS. For the simulated extended sized problems that resemble the complexity of a problem faced by a small city, the results prove that DEM-T not only achieves optimality, but also produces sets of multiple alternate optimal solutions. These could be very helpful in practical settings when alternate solutions are necessary because some solutions may not be deployable due to unforeseen circumstances. / text

The widely-used passenger and car ferries, sailing regularly and carrying heavy loads, form a unique type of marine vessel, providing vital transportation links to the coastal regions. Modern ferry ships usually are equipped with multiple diesel engines as prime movers. These diesel engines consume a large amount of marine diesel fuel with high fuel costs, and high emissions of greenhouse gas (GHG) and other harmful air pollutants, including CO2, HC, NOx, SO2, CO, and PM. To reduce fuel costs and the harmful emissions, the marine industry and ferry service providers have been seeking clean ship propulsion solutions. In this work, the model-based design (MBD) and optimization methodology for developing advanced electrified vehicles (EV) are applied to the modelling, design and control optimizations of clean marine vessels with a hybrid electric propulsion system. The research focuses on the design and optimization of the hybrid electric ship propulsion system and uses an open deck passenger and car ferry, the MV Tachek, operated by the British Columbia Ferry Services Inc. Canada, as a test case. At present, the ferry runs on the Quadra Island – Cortes Island route in British Columbia, Canada, with dynamically changing ocean conditions in different seasons over a year. The research first introduces the ship operation profile, using statistical ferry operation data collected from the ferry’s voyage data recorder and a data acquisition system that is specially designed and installed in this research. The ship operation profile model with ship power demand, travelling velocity and sailing route then serves as the design and control requirements of the hybrid electric marine propulsion system. The development of optimal power control and energy management strategies and the optimization of the powertrain architecture and key powertrain component sizes of the ship propulsion system are then carried out. Both of the series and parallel hybrid electric propulsion architectures have been studied. The sizes of crucial powertrain components, including the diesel engine and battery energy storage system (ESS), are optimized to achieve the best system energy efficiency. The optimal power control and energy management strategies are optimized using dynamic programming (DP) over a complete ferry sailing trip. The predicted energy efficiency and emission reduction improvements of the proposed new ship with the optimized hybrid propulsion system are compared with those of two benchmark vessels to demonstrate the benefits of the new design methodology and the optimized hybrid electric ship propulsion system design. These two benchmarks include a conventional ferry with the old diesel-mechanical propulsion system, and the Power Take In (PTI) hybrid electric propulsion systems installed on the MV Tachek at present. The simulation results using the integrated ship propulsion system model showed that the newly proposed hybrid electric ship could have 17.41% fuel saving over the conventional diesel-mechanical ship, and 22.98% fuel saving over the present MV Tachek. The proposed optimized hybrid electric propulsion system, combining the advantages of diesel-electric, pure electric, and mechanical propulsions, presented considerably improved energy efficiency and emissions reduction. The research forms the foundation for future hybrid electric ferry design and development. / Graduate

The male gametes (sperms) are under strong sexual selection and are therefore very diverse in their morphology and often differ even amongst closely related species. Sperms are thus assumed to play very important role in reproductive isolation between species, due to their fast evolution in morphology. In my master thesis, I have studied the possible role of sperm morphology divergence in reproductive isolation in two sister species of passerine birds, the common nightingale (Luscinia megarhynchos) and the thrush nightingale (L. luscinia). The areas of these species overlap in secondary contact zone running across central and Eastern Europe, where they occasionally hybridize. I have compared sperm morphology of males of both species originating in allopatric and sympatric localities as well as interspecies hybrids. The results showed significant differences in total sperm length which is approximately 20 % longer in the common nightingale. That is caused by great interspecies divergence in midpiece (containing mitochondria) length. Interspecific hybrids showed sperms with intermediate length but despite expectations completely morphologically normal. This outcome corresponds with observed fertility in F1 hybrid males. What I consider to be an essential finding is a significant divergence in head...

Call number: LD2668 .T4 1948 V35 / Master of Science

In recent years an increase of agile methodologies and their implementation in mainstream software engineering projects have been seen, but this implementation has reportedly changed agility in practice into a hybrid form of agility and more classic methodologies. With a lack of research regarding these hybrid methodologies this multiple case study empirically analyses the practice of methodologies from two different conglomerates and places the results in the Information Technology Management framework (ITMF) to answer the research question; How are hybrid agile methodologies enacted in practice in mature agile teams and why are they enacted in such a way? The result show that the organizations work agile within a waterfall framework, a hybrid form of requirement handling into agile development followed by waterfall testing. The hybrid methodologies are imposed by external factors such as the sales department and traditional economic reporting. This study acknowledges a need for a greater understanding of the engagement between external actors and software development.

Methods of noise coupling in high speed thick film circuits has been investigated. Parasitic coupling parameters have been experimentally determined for a variety of single and multilayer thick film layouts. In addition, the severity of the problem has been studied by measuring coupled noise induced on carefully constructed test cards. Curves are presented as an aid for predicting noise levels as a function of conductor spacing and signal edge speed. The measurements are discussed quantitatively and guidelines for the design of high speed thick film circuits are summarized.

ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / In this article we present results from modeling and simulation of a L-band reflection type phase shifter (RTPS) that provides continuous phase shift of 0° to 360°. The RTPS circuit uses a 90º hybrid coupler and two reflective load networks consisting of varactor diodes and inductors. Proper design of 90° hybrid coupler is critical in realizing maximum phase shift. The RTPS circuit implemented on a Rogers Duroid substrate is large in size. We discuss methods to reduce the size of L-band RTPS.

International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / In this paper, a hybrid frequency division multiple access/code division multiple access (FDMA/CDMA) system in a Rician fading channel is described and analysis. The performance of the hybrid system is compared with a wideband CDMA system, which occupies the same total bandwidth. The results show that for DPSK modulation with a RIKE receiver, a hybrid system can have a greater capacity with a strong direct path component or a high signal to noise ratio (SNR). Otherwise, a wideband system remains optimal.