This diploma thesis deals and comprehensively unifies the theoretical knowledge in the field of turning, grooving and parting of material. Furthermore, the thesis also deals with the theory of cutting tool materials as well as tool’s construction and shape characteristics. In the practical part of the thesis there is proposed procedure and conditions necessary to perform the experiment of the tool force loaded measurements, as well as the technical description of the grooving process. Last but not the least, all the measured data is evaluated and plotted into dependencies, from which the results and recommendations for the optimal groove cutting with the particular cutting tool are made.

The aim of this study was to evaluate the effect of the type of lubricant, its concentration and mixing time with granules on the tablet hardness, ejection force and the lubrication index. Lactose was used as a filler in granules and polyvinylpyrolidone as a binder. Granules were prepared by wet granulation. Three types of talc were used in concentrations 1%, 3%, 5%, 7% a 10% and magnesium stearate in concetrations 1%, 2% a 3% as lubricants. Tablets were produced by tablet press DOTT Bonapace (model CPR-6) with the possibility to measure the force of the upper and lower punch and force-displacement. These values were used for the calculation of the lubrication index. The values of lubrication index were used for the lubricants comparison. The lubrication index with magnesium stearate did not change either with increasing concentration or with mixing time with granules. In case of each type of talc, the lubrication effect rose with increasing concentration but time of the mixing did not have any significant effect on the lubrication potential. Tablet strength decreased with higher lubricant concentration and longer mixing time when magnesium stearate was used. With increasing concentration of the lubricant tablet strength with talc first increased then stagnated or started to decrease. The higher...

The stability of myosin subfragment 2 was analyzed using gravitational force spectroscopy. The region was found to destabilize under physiological force loads, indicating the possibility that subfragment 2 may uncoil to facilitate actin binding during muscle contraction. As a control, synthetic cofilaments were produced to discover if the observations in the single molecule assay were due to the lack of the stability provided by the thick filament. Statistically, there was no difference between the single molecule assay data and the synthetic cofilament assay data. Thus, the instability of the region is due to intrinsic properties within subfragment 2.

The dissertation presents the mathematical formulation, experimental validation, and application of a volume element model (VEM) devised for modeling, simulation, and optimization of energy systems in their early design stages. The proposed model combines existing modeling techniques and experimental adjustment to formulate a reduced-order model, while retaining sufficient accuracy to serve as a practical system-level design analysis and optimization tool. In the VEM, the physical domain under consideration is discretized in space using lumped hexahedral elements (i.e., volume elements), and the governing equations for the variable of interest are applied to each element to quantify diverse types of flows that cross it. Subsequently, a system of algebraic and ordinary differential equations is solved with respect to time and scalar (e.g., temperature, relative humidity, etc.) fields are obtained in both spatial and temporal domains. The VEM is capable of capturing and predicting dynamic physical behaviors in the entire system domain (i.e., at system level), including mutual interactions among system constituents, as well as with their respective surroundings and cooling systems, if any. The VEM is also generalizable; that is, the model can be easily adapted to simulate and optimize diverse systems of different scales and complexity and attain numerical convergence with sufficient accuracy. Both the capability and generalizability of the VEM are demonstrated in the dissertation via thermal modeling and simulation of an Off-Grid Zero Emissions Building, an all-electric ship, and a vapor compression refrigeration (VCR) system. Furthermore, the potential of the VEM as an optimization tool is presented through the integrative thermodynamic optimization of a VCR system, whose results are used to evaluate the trade-offs between various objective functions, namely, coefficient of performance, second law efficiency, pull-down time, and refrigerated space temperature, in both transient and steady-state operations. / A Dissertation submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / Summer Semester 2016. / July 7, 2016. / energy systems, system-level modeling, systems engineering, thermal simulation, thermodynamic optimization, volume element model / Includes bibliographical references. / Juan C. Ordo˜nez, Professor Directing Dissertation; David A. Kopriva, University Representative; Simone P. Hruda, Committee Member; Steven W. Van Sciver, Committee Member.

Gold nanoparticles (Au NPs) are widely studied due to the ease of controlled synthesis, facile surface modification, and interesting physical properties. To fully take advantage of the NP properties, self-assembly of colloidal Au NPs into ordered structures is an essential step. Of all self-assembled structures, the two-dimensional (2D) film composed of just a single layer Au NPs is the simplest one. Yet, 2D Au NP monolayers are of key importance for both fundamental studies and numerous applications such as plasmonics, optics, sensors and catalysts. However, the self-assembly of the 2D Au NP monolayers of both microscopic (i.e. 100 nm²) and macroscopic (i.e. >cm²) order is quite challenging. The major contribution of this research is to develop effective methods to self-assemble Au NPs of various sizes into monolayers using a broad range of ligands. Two methods have been developed for this purpose, namely the "drain-to-deposit" method and the "three-phase self-assembly" technique. The resultant Au NP monolayers have been found ideal to study the polymer ligand chain configuration indicated by the interparticle space. In addition, the Au NP monolayers serve as promising surface-enhanced Raman spectroscopy (SERS) substrates and are useful to study lithium battery electrolyte s. / A Dissertation submitted to the Department of Chemical and Biomedical Engineering in partial fulfillment of the Doctor of Philosophy. / Spring Semester 2017. / March 27, 2017. / gold nanoparticle, lithium battery, polymer, self-assembly, surface-enhanced Raman scattering, thin film / Includes bibliographical references. / Daniel T. Hallinan, Jr., Professor Directing Dissertation; Jianping (Jim) Zheng, University Representative; Rufina G. Alamo, Committee Member; Jingjiao Guan, Committee Member; Zhiyong (Richard) Liang, Committee Member.

The first chapter examines what motivates airports to deploy on-site solar PV system. Currently, over 20% of U.S. public airports have adopted solar photovoltaic (PV) on their property. Yet, the vast majority of research on solar energy adoption focuses on state, local, or individual levels, largely overlooking one of the most utilized public properties for solar PV—airports. Combining a unique dataset of 488 U.S. public airports and interviews with managers at four key airports, this paper investigates why and to what degree (i.e., capacity generated) do airports deploy on-site solar PV systems. Findings suggest state-operated airports are more likely to adopt solar PV, airports in the service area of cooperatives are less likely to deploy solar PV, and the level of connectivity to other airports in airport associations positively correlates to solar PV adoption and capacity. Airport governance, support from electric utilities, and renewable policy incentives are also important factors influencing solar and renewable energy development. Policy and management implications for renewable energy deployment at airports and other publicly-used properties are discussed. Insight for future research on the general linkage between governance structure and renewable energy development is considered. The second chapter examines make-or-buy decisions (i.e., providing in-house or contracting out) in financing solar PV projects at U.S. airports. Airports are one of the fastest growing adopters of solar photovoltaic (PV) energy systems, but little is known about how airports finance solar projects. Financing arrangements can influence long-term economic viability and cost-benefit distribution of solar projects. Based on the transaction cost approach, this paper hypothesizes that make-or-buy decisions for solar projects are shaped by airport governance structure, utility ownership, state policies, and renewable market conditions. Hypotheses are examined through multinomial logistic analysis, using data from all U.S. airports that have adopted a solar PV project as of June 2018. The analysis finds that airports operated by special-purpose governments are more likely to own and self-operate solar systems, while airports in the service area of investor-owned utilities are more likely to lease land for a solar project. Statewide renewable energy regulations and solar market conditions are also important factors influencing make-or-buy decisions. This chapter has implications for solar PV policy design, taking into account positive externalities of renewable energy projects given institutional environments. The third chapter examines how local government organizational characteristics and management activities relate to public-nonprofit collaboration and perceived performance in local sustainability. Local governments have been increasingly responsible for promoting sustainability, but we are only beginning to learn how organizational characteristics and management activities influence local sustainability policy. Using 2015 sustainable cities survey data and case studies in the U.S., this study finds that public-nonprofit collaboration in sustainability is positively associated with perceived inter-departmental competition and functional fragmentation. It is also found that perceived sustainability performance is positively correlated with public-nonprofit collaboration, functional fragmentation, and performance information use. However, the relationship between performance information use and perceived performance is nonlinear, indicating that the effect of performance information use on perceived performance has an inverse u-shape. Performance information use in highly fragmented administrative arrangements may be negatively related to perceived sustainability performance. Implications for local sustainability implementation are discussed. / A Dissertation submitted to the Askew School of Public Administration and Policy in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / 2019. / [Date awarded not present on Dissertation]. / airport governance, bureaucratic competition, local sustainability, performance information, renewable energy policy, special purpose governance / Includes bibliographical references. / Richard C. Feiock, Professor Directing Dissertation; Charles Barrilleaux, University Representative; Ralph S. Brower, Committee Member; Kaifeng Yang, Committee Member.

Skeletal muscle has been used for biomechanical assist in experimental and clinical studies. Central to the success of these procedures is the generation of sufficient muscle force for the lifetime of the subject. Burst (tetanic) stimulation results in summation of individual twitches and generates higher power output. However, the superiority of paraneural versus intramuscular as well as proximal versus middle and distal intramuscular stimulations remains unclear. Electrophysiological mapping and mechanical performance of seven canine latissimus dorsi muscles were analyzed. The mechanism of higher tension generation produced by: (1) increased temporal summation; (2) greater motor units activated; or (3) result of both were determined. The parameters primarily dependent on the number of activated motor units are significantly greater following paraneural and proximal intramuscular stimulations. The parameters mainly related to temporal summation are not different between various electrode configurations. For intramuscular stimulation, it is the location of interelectrode field rather than the location of the cathode perse that determines the mechanical performance of the skeletal muscle. Furthermore, tension development of skeletal muscle is primary nerve activation rather than direct muscle stimulation. The higher tension generation that resulted from different electrode configurations is produced by activating a higher number of muscle fibers through the neuromuscular junctions.

Overtraining is a common problem in athletes that prevents many from becoming "elite". A decrement in an athlete's performance is usually an indicator that overtraining syndrome may be developing. Unfortunately, there is no model that can determine overtraining. A decline in performance results in a depression in maximum muscular force. It is not known whether the force depression is a result of central or peripheral factors. In this study, the two training protocols on different legs determined whether force declines are muscular (peripheral) or psychological (central). Specifically, in this study, the subjects trained one leg at maximal intensity for two weeks, and the other trained at a low intensity for two weeks. After training for two weeks, both legs were placed on a low intensity workout to monitor the recovery process. The purpose of this study was to observe muscle strength performance decrements after overtraining one leg in comparison to properly training the other leg by knee extension exercises for two weeks in trained males. Also, after overtraining the one leg for two weeks, the leg was placed on a reduced training program in order to look at recovery if overtraining occurred. Maximal force output was measured isokinetically on the Biodex three times: pre-, post-, and final test. An analysis of this data revealed no significant changes in maximal muscular force output after a high intensity training protocol. Therefore, this investigation demonstrated that overtraining in the quadricep did not result from the two weeks of high intensity resistance training. / Master of Science

Recent years have seen developments in lithium-ion capacitor (LIC) technology. However, there has been scant work in mathematical models to predict the performance of LICs. Existing models have focused upon cell degradation over time or simple Randles circuits to describe laboratory work. Experimentalists have determined that LICs’ energy storage capabilities are inversely proportional to their charge or discharge (dis/charge) current. But this phenomenon is not well understood, a serious barrier to LIC market entry as designers struggle to predict the energy storage of LICs under design. This study begins with an experiment on applying lithium to LICs. Then it discusses a study on the cycle life of LICs. Earlier studies had found the degradation of LICs cycled at constant current but different temperatures can be described by an Arrhenius equation. This cycle life study found that when an LIC is cycled at a constant temperature but different cycle currents the results can also be described by an Arrhenius equation, which can be derived from the Arrhenius equation describing degradation as a function of current. The Butler-Volmer equation anticipates these results because it predicts direct proportionality between a LIC’s cycle current and temperature. The predictive model, which comprises the bulk of this research, began with electrochemical impedance spectroscopy experiments (EIS) on an LIC to build a Randles equivalent circuit model (ECM) describing the same LIC. This LIC was then charged at several constant powers, recording the stored energy. Using the Randles ECM, simulated LICs were charged at these same constant powers, yielding high fidelity at low power but significant error at high power. In order to solve this high power inaccuracy, all of the experimentally-derived values, except for the series resistance and Warburg resistance, were replaced by physics equations that would compute these values. The Butler-Volmer equation was manipulated to express dis/charge current in terms of temperature, which computed the Warburg capacitance and dis/charge transfer resistance, key elements in a Randles ECM. This change yielded an accurate energy computation, but not an accurate voltage computation. Furthermore, the temperature values computed by the Butler-Volmer equation were unrealistic and could not be reconciled mathematically. The next iteration of the study involved in situ temperature measurements of LICs during dis/charge cycles. These in situ measurements indicated that temperature change is only observed during low power dis/charges, and even then it is <1% of absolute temperature. This indicates that although the Butler-Volmer equation can express LIC temperature in terms of dis/charge current, temperature can be treated as a constant without much loss in model fidelity. Warburg impedance was observed to be computed in terms of temperature and is almost constant, like temperature. Series resistance negligibly affects voltage change or energy stored in an LIC. This is the first known physics-based model to predict an LIC’s energy storage as a function of its dis/charge current and constituent components. This model also explains the current-energy inverse relationship observed in LICs using a new derivation of the Butler-Volmer equation. This model may have significant commercial value for LIC designers in the future as it eliminates a significant barrier to market entry. / A Dissertation submitted to the Department of Electrical and Computer Engineering in partial fulfillment of the requirements for the degree of Doctor of Philosophy. / 2019 / October 3, 2019. / Arrhenius equation, Butler-Volmer equation, lithium-ion capacitor, model, Randles equivalent circuit model, Warburg impedance / Includes bibliographical references. / Simon Foo, Professor Directing Dissertation; Anke Meyer-Baese, University Representative; Petru Andrei, Committee Member; Rodney Roberts, Committee Member; Zhibin Yu, Committee Member.

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