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As natural resources are decreasing and environmental pollution is increasing, the buildings that play an important role in this problem should be constructed sustainably so their affects are kept to a minimum. Hospitals operate 24 hours a day and 7 days a week, therefore they are one of the largest energy consumers. Hence designers have started to design healthcare facilities according to the Leadership in Energy and Environmental Design (LEED) criteria, believing that it will reduce waste production, energy consumption and increase patient satisfaction by creating brighter and less stressful facilities. To understand if the claims are correct or not, this thesis first studied the results of the patient survey, Hospital Consumer Assessment of Healthcare Providers and System (HCAHPS), undertaken at most of the hospitals in the U.S., and compares the results to LEED and non-LEED certified hospitals. To find answers for the claims related to the financial benefits, this thesis compared three financial indicators; cost of operation of plant, profitability, and inpatient revenue. In the cases where there is a large enough sample size, a t-test is used to compare two groups, however when the sample size was not large enough, two groups are compared based on their means. For the cost of operation of plant and profitability, non-LEED certified hospitals are performing better. However, the patient satisfaction and inpatient revenues are significantly higher at the LEED-certified hospitals.

Leadership in small and medium enterprises (SMEs) has remained an under-researched area in the management literature, especially in developing countries such as Nigeria. SME owner-managers in Nigeria lacked in-depth understanding of their leadership style to objectively evaluate its implication on long-term performance and growth of their enterprise. The purpose of this qualitative multiple-case study was to explore the experiences of SME owner-managers in Nigeria to gain an in-depth understanding of their leadership style and its implication for long-term performance and growth of their enterprise. The conceptual framework for this study was anchored in two key concepts; leadership styles and leadership in SMEs, with the full range leadership model as the theoretical foundation. The research question sought to explore the role of SMEs owners and managers leadership styles in the long-term success of their enterprise. Interview data were collected from 6 SME owner-managers who employ less than 200 employees within the manufacturing, education, and trading sectors. The cross-case synthesis technique was used for data analysis which allowed for within-case analysis and cross-case comparisons. Findings from this study showed that Nigerian SME owner-managers do not follow any specific leadership style. They exhibited few characteristics of transformational and transactional leadership behaviors, leaning more to transactional leadership. This study has significance for positive social change by providing insights on how leadership styles can improve the performance and sustainability of Nigerian SMEs, thus increasing their capacity to create employment.

One of the major problems with using renewable energy is the mismatch between power generation and demand as renewable energy generation and energy usage from HVAC equipment depend on unsynchronized natural factors. To reduce this supply-demand mismatch many researchers suggested using thermal energy storage to shift cooling and/or heating loads. A thermal energy storage (TES) tank can be integrated with building heating and cooling systems using several methods described in the open literature. This thesis explores a novel method to integrate water-based TES with an indoor air coil using a three fluid heat exchanger (TriCoil(TM)). The three fluid heat exchanger will thermally connect water from the TES, refrigerant from the outdoor unit, and indoor air. A test setup has been developed inside the Psychrometric Coil Testing Facility of Oklahoma State University (OSU) to test the TriCoil(TM). The heat balance of the test setup for different operation modes and test points was within +/-5%. An uncertainty analysis has been performed on the test results and major sources of uncertainties have been identified. In the experiment done for this thesis, water from the TES was successfully charged up to 15 kW (cooling) with a log mean temperature difference (LMTD) of 18.5 K using a 4-ton capacity outdoor unit. TriCoil(TM) was also used to discharge the water from TES with a max capacity of 11.5 kW (heating) with an LMTD of 8.7 K, a water flow rate of 1700 kg/h, and an airflow rate of 1600 CFM.

A single dose of additive contributes to three consecutive fine coal unit operations, i.e., flotation, dewatering and reconstitution, whereby the fine coal is first combined with water in a predetermined proportion so as to formulate a slurry. The slurry is then mixed with a heavy hydrocarbon-based emulsion in a second predetermined proportion and at a first predetermined mixing speed and for a predetermined period of time. The conditioned slurry is then cleaned by a froth flotation method to form a clean coal froth and then the froth is dewatered by vacuum filtration or a centrifugation process to form reconstituted products that are dried to dust-less clumps prior to combustion.

"The microwave wireless power transfer system can be divided into five elements, including energy emission component, energy harvesting module, energy storage component, power conditioning component and functioning module. This dissertation is dedicated to developing a new class of microwave wireless power transfer system by investigating the first three elements. To increase the energy harvesting efficiency, the metamaterial absorber based energy harvesting device was introduced. The investigation to this new device started with a transmission line model to characterize the metamaterial absorber and followed by demonstration in both simulation and experiment for the energy harvesting based on metamaterial absorber with varies of substrate materials. Both simulation and experimental results are qualitatively consistent with the transmission line model prediction that the signal transfer ratio reduces when the dielectric loss of the substrate increases. The highest experientially demonstrate signal transfer ratio reaches 96% when using Rogers 5880LZ as the substrate material. In order to increase the transmission efficiency between the emission component and energy harvesting module, it is desired to identify the incident wave direction from the energy harvesting perspective and enhance the antenna gain from both emission and energy harvesting perspectives. To identify the incident wave direction, we have adapted the basic design of metamaterial absorber to fabricate a microwave subwavelength imaging device. Similar to an optical camera, such device is able to track the incident wave direction when combining with a microwave lens. The performance test of the imaging device based on metamaterial absorber has shown that it can not only identify the position of the focused beam with an accuracy of 1% wavelength in the far field imaging test, but also is capable of carrying out near field imaging by capturing the electromagnetic power distribution with ignorable distortion to the original power distribution. The gain enhancement was proposed by placing a artificial magnetic conductor (AMC) underneath the radiation antenna. AMC is able to reflect the microwave with a phase shift of between -90 and 90 degree in a frequency band, call in-phase reflection band. We have built a transmission line model for AMC. Derivation based on this transmission line model reveals that the in-phase reflection bandwidth has a theoretical limit as a function of the thickness and permeability of AMC substrate. The method of making the in-phase reflection bandwidth of an AMC sample approaching its theoretical limit has been proposed. Experimentally, a ratio to the theoretical limit of 98.5% has been achieved, which is the highest compared to a number of reported values in AMC simulation and experiment results. By comparing out proposed method to two previously reported methods, we found that our proposed method gives more restricted value. Finally, work has been carried out to develop a new class of energy storage component for the microwave wireless transfer system. A Fe-Ni based electrochemical negative electrodes has been experimentally demonstrated by sintering chemically prepared Fe–Ni nanoparticles into a nanoporous pellet with thickness of 65 μm and mass loading density of 20 mg/cm-2. This electrode is consisted of nanoscale mixture of an Fe-rich body-centered cubic Fe(Ni) phase and a Ni-rich face-centered cubic Fe–Ni phase. The high conductive and structure stability is provided by the Ni-rich phase and the electrochemically active component of the electrodes is produced by the selective conversion of the Fe-rich phase to hydroxides. The experimental measurement shows the compositionally optimized electrodes exhibit a specific capacitance in excess of 350 F/g by normalizing to the whole electrode mass and retain more than 85% of their maximum specific capacitance after 2000 charging/discharging cycles. This desirable combination of physical and electrochemical properties indicates that such electrodes may be useful as the negative electrode in high performance asymmetric supercapacitors."

Analyzed wind resource characteristics at elevated heights (50 m-200+m) incuding shear and turbulence profiles for some areas of the Great Lakes and M idwest sites.

A strontium atomic source is characterized in terms of flux and angular distribution in this project. Beam collimation via a microcapillary nozzle is studied and tested against theoretical models. Further improvement of the atomic beam via one-dimensional transverse cooling is demonstrated.

Cooling is a critical part of data center’s infrastructure, and with ongoing demands in data processing and storage, thermal management issues are of great concern. Some imperative methods of removing heat are either using air or liquid (preferably water or refrigerant). When high power density modules are involved, liquid cooling addresses some of the problems faced by air cooling as liquid coolants have higher thermal capacitance. Also, in the case of multi-chip modules, a non-uniform heating due to multi-core generates hot-spots and increases temperature gradients across the module. A dynamic cold plate along with a self-regulated flow control device was developed to address these issues. A temperature sensing self-regulated flow control device (FCD) is placed at the exit of each section to regulate the required flow. But to implement this at rack level, a good control strategy is required. This study presents a CFD analysis of such control strategy to save Pumping power on a direct liquid cooled rack using a concept of dynamic cooling along with a self-regulated flow control device. It’s important to save pumping power as it is one of the most energy consumed areas in the data center. The main objective of this study is to assess the flow rate and pressure distribution on the rack in order to control excessive pumping power usage and enhance cooling system efficiency.

With an ever-growing population, global energy demand increases, thereby contributing to the depletion of fossil resources and their limited reserves. Thereby, to lessen the environmental damage caused by fossil fuels, there has been a surge of interest in developing and producing biofuels from renewable feedstocks, such as microbial lipids. Typically, they are derived via a biochemical process using liquid hydrolysates obtained from forestry residues as a substrate. However, microbial lipid production using hydrolysates presents numerous challenges, including the need for a strain that can accumulate high lipid titers, consume five-carbon sugars (C5), and tolerate inhibitory compounds (e.g., furans, phenols, and organic acids), among others. Out of several microorganisms, Rhodosporidium toruloides, an oleaginous yeast, could be a potential alternative to produce lipids. It is known to accumulate lipids up to 70% of its dry cell weight, use different carbon sources, and tolerate several inhibitory compounds. In this sense, the current thesis explores the ability of Rhodosporidium toruloides as a bio-factory to produce microbial lipids using C5 and C6 wood hydrolysates as a culture media. Different R. toruloides strains were screened, and R. toruloides-1588 was determined to have the highest lipid accumulation of 35%. Following the culture media, carbon to nitrogen ratio, use of lipid inducers, and sugar concentration optimization, the lipid accumulation increased from 35% to 57.14%, with 95% and 80% of glucose and xylose utilization in hydrolysates, respectively. Likewise, palmitic, stearic, and oleic fatty acids were the most prominently on the produced lipids. Finally, R. toruloides-1588 demonstrates the capacity to grow, accumulate lipids, and transform furfural into furfuryl alcohol and 2-furoic acid. The strain was also assessed for its ability to tolerate inhibitory compounds, such as 5-hydroxymethyl furfural, vanillin, syringaldehyde, levulinic acid, ferulic acid, acetic acid, vanillic acid, and ...

The merging of empirical tests and theoretical models allows us to make sense of complex biological concepts. This thesis explores questions of biological variation (both within and between species) and its persistence through evolutionary time scales primarily through the development of mechanistic models. The first chapter uses a game theory framework to describe drivers of persistence in systems of alternative strategies, and presents a new framework to describe competition within large systems. The second chapter describes the plastic system of developmental polyphenisms in the Mexican spadefoot toads, Scaphiopus multiplicata using a game theory framework. The possibility that anthropogenic climate change will alter selection on developmental polyphenisms is explored. The third chapter uses a mechanistic ecophysiology-based model to explore extinction risk in seven species of tropical New World day geckos (Sphaerodactylidae, Squamata). These studies highlight the importance of incorporating empirical data in modeling. Given anthropogenic changes to climate and habitat availability, ecosystem resilience of particular concern to conservationists. We need tools to predict how species losses will affect eventual equilibrium outcomes – whether ecosystems will survive in a recognizable state, or whether the loss of key species can affect larger-scale stability.