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Imbulgoda Liyangahawatte, Gihan Janith MendisHardware Implementation and Applications of Deep Belief Networks
Master of Science in Engineering, University of Akron, 2016, Electrical Engineering
Deep learning is a subset of machine learning that contributes widely to the contemporary success of artificial intelligence. The essential idea of deep learning is to process complex data by abstracting hierarchical features via deep neural network structure. As one type of deep learning technique, deep belief network (DBN) has been widely used in various application fields. This thesis proposes an approximation based hardware realization of DBNs that requires low hardware complexity. This thesis also explores a set of novel applications of the DBN-based classifier that will benefit from a fast implementation of DBN. In my work, I have explored the application of DBN in the fields of automatic modulation classification method for cognitive radio, Doppler radar sensor for detection and classification of micro unmanned aerial systems, cyber security applications to detect false data injection (FDI) attacks and localize flooding attacks, and applications in social networking for prediction of link properties. The work in this thesis paves the way for further investigation and realization of deep learning techniques to address critical issues in various novel application fields.

Committee:

Jin Wei (Advisor); Arjuna Madanayaka (Committee Co-Chair); Subramaniya Hariharan (Committee Member)

Subjects:

Artificial Intelligence; Computer Engineering; Electrical Engineering; Engineering; Experiments; Information Technology

Keywords:

deep belief networks; multiplierless digital architecture; Xilinx FPGA implementations; low-complexity; applications of deep belief networks; spectral correlation function; modulation classification; drone detection; doppler radar; cyber security

Baker Christensen, Leslie MichelleArtistic Drawing as a Mnemonic Device
Psy. D., Antioch University, 2016, Antioch Seattle: Clinical Psychology
Despite art-based learning being widely used, existing data are primarily qualitative, and most research has not isolated particular variables such as memory for empirical study. The few experiments that have been conducted demonstrated that drawing improves free recall of unpaired words, and retention improves after lessons integrated with drawing, drama, and narrative exercises. To help fill the gap in the current literature, the present study compared the effectiveness of encoding and the rate of memory decay between a drawing mnemonic and note taking on a paired associates task. Using a within-subjects experimental design, participants were presented with word pairs and asked to complete either a drawing mnemonic (DM) or note taking (NT) to assist memorization. Participants were tested immediately after the word pair presentation and after a 20-minute delay. Results supported the hypothesis that the DM condition would produce superior encoding, as evidenced by greater retention on the immediate test. However, no memory decay was observed in the experiment, and therefore results on the delayed test were inconclusive. In fact, scores for the NT condition improved over time whereas the scores for the DM condition did not, which might imply that note taking results in a different consolidation process than drawing. Findings from this study suggested that arts integration can be an effective method to support memory for learned information. Future studies that examine the effect of rehearsal and the long-term effectiveness of a drawing mnemonic are warranted. This dissertation is available in open access at AURA, http://aura.antioch.edu/ and Ohio Link ETD Center, https://etd.ohiolink.edu/etd

Committee:

Suzanne Engelberg, Ph.D. (Committee Chair); Jude Bergkamp, Psy.D. (Committee Member); Luke Rinne, Ph.D. (Committee Member)

Subjects:

Education; Experimental Psychology; Experiments; Psychology; Teaching

Keywords:

art-based learning; arts-integration; drawing; experiment; learning; memory; mnemonics; paired associates; quantitative; within-subjects

Alsubail, Rayan A.Aesthetics vs. Functionality in User Prompt Design: A Mobile Interface Usability Study on the iOS Touch ID Feature
Master of Science (MS), Ohio University, 2015, Computer Science (Engineering and Technology)
The usability of smartphone software presents unique challenges as compared to desktop software. Both aesthetics and functionality play an important role in mobile interface design. In this paper, we examined the usability of the iOS Touch ID feature with different user prompts. We compared three different types of user prompt designs for the touch ID feature, including a user prompt with no guidance (NG), a user prompt with aesthetic-first guidance design (AF), and a user prompt with functionality-first guidance design (FF). An experiment with 30 participants showed an improvement for 90% of them when using the FF prompt for the fingerprint inputs, as compared to when using the AF prompt. Additionally, the fingerprint inputs were improved for all participants using the FF prompt as compared to the NG prompt. We concluded that user prompt designs do have a material impact on the usability of mobile software, and that functionality rather than aesthetics should be the primary consideration in user prompt design.

Committee:

Chang Liu (Advisor); Frank Drews (Committee Member); Jundong Liu (Committee Member)

Subjects:

Computer Engineering; Computer Science; Experiments

Keywords:

Usability; Touch ID Usability; Touch ID; iPhone Usability; Interface Design; User Prompt Design; Aesthetic; Aesthetic Design; Aesthetic and Usability

Friedrich, Brian KarlAn Experimental Study of Volumetric Quality on Fluid Flow and Heat Transfer Characteristics for Two Phase Impinging Jets
Master of Science in Engineering, Youngstown State University, 2016, Department of Mechanical and Industrial Engineering
This study further expands the current knowledge of the relationship between heat transfer and fluid mechanics. Fluid flow and heat transfer characteristics of air-assisted water jet impingement was experimentally investigated under a fixed water flow rate condition. Water and air were the test fluids. The effects of volumetric quality (ß = 0 – 0.9) on the Nusselt number, hydraulic jump diameter, and pressure were considered. The results showed that stagnation Nusselt number, hydraulic jump diameter, and stagnation pressure increased with volumetric quality to a maximum value at 0.8 of the volumetric quality, and then decreased. The stagnation Nusselt number and hydraulic jump diameter of the air assisted water jet impingement are governed by the stagnation pressure. Based on the experimental results, a new correlation for the normalized stagnation Nusselt number and hydraulic jump are developed as a function of the normalized stagnation pressure alone. This research can be applied to further enhance the cooling of industrial applications, such as, cooling of electronics and processing of materials.

Committee:

Kyosung Choo, PhD (Advisor); Guha Manogharan, PhD (Committee Member); Jae Joong Ryu, PhD (Committee Member)

Subjects:

Experiments; Fluid Dynamics; Mechanical Engineering

Keywords:

impinging jet; Hydraulic Jump; two phase; two-phase; fluid flow; Heat transfer; jet impingement; Volumetric quality;

Walia, PiyushThe Effect of Combined Bony Defects on the Anterior Stability of the Glenohumeral Joint and Implications for Surgical Repair
Doctor of Engineering, Cleveland State University, 2015, Washkewicz College of Engineering
The combined defects of the glenoid and humeral head defects are often associated with recurrent anterior instability. Past studies have only investigated the effects of isolated humeral head or glenoid defects. A cadaveric model was developed to investigate the effect of combined defects. Moreover, two different finite element models were developed to validate against the experimental data. It was hypothesized that combination of smaller sizes of the two defects would reduce the glenohumeral joint’s stability. Furthermore, it was hypothesized that the instability due to humeral head defect will be dependent on the arm position but this won’t be the case for the glenoid defect. Also, it was believed that both specimen-specific and population-based models will validate against the experimental data. Different sets of simulation were run with both isolated and combined defects to analyze the reaction forces and calculate distance to dislocation. The experiments were performed with displacement control under a 50N compressive load. The results from the study predicted a statistical model that explained the direct correlation between the anterior stability of glenohumeral joint and the size of the defect. It was found that with the increase in size of the defect, the distance to dislocation decreased. It was determined that a combination of 10% glenoid defect with a 19% humeral head defect resulted in lower stability (p<0.05) than that of an isolated 20% glenoid defect. Results from finite element analysis showed that both specimen-specific and population-based models were similar to cadaveric model.

Committee:

Stephen Fening, Ph.D. (Committee Chair); Antonie van den Bogert, Ph.D. (Advisor); Anthony Miniaci, M.D., F.R.C.S.C. (Committee Member); Morgan Jones, M.D., M.P.H (Committee Member); Ahmet Erdemir, Ph.D. (Committee Member); Brian Davis, Ph.D. (Committee Member)

Subjects:

Biomechanics; Biomedical Engineering; Biomedical Research; Design; Engineering; Experiments; Mathematics; Pathology; Sports Medicine

Keywords:

Shoulder, Glenohumeral Joint, Anterior Instability, Combined Bone Defects, Hill-Sachs Defect, Bony Bankart Lesion, Humeral Head Bone Loss, Bipolar Defects, Concavity Depth, Stability Ratio

Jackson, Richard AramA Preliminary Study of Pump/Probe Angular Dependence of Zeeman Electromagnetically Induced Transparency
Master of Science, Miami University, 2015, Physics
This thesis outlines my work to determine the dependence of Zeeman Electromagnetically Induced Transparency (EIT) on the relative angle between the pump and probe beams. We report initial measurements of Zeeman EIT and EIA using a simple arrangement in which the Zeeman sublevels are scanned around fixed pump and probe frequencies. We introduce improvements in magnetic field uniformity and measure EIT/EIA feature lineshape vs. pump/probe angle. Next, we outline our progress on performing Zeeman EIT/EIA experiments in the traditional format, i.e. scanning the probe frequency while holding the pump frequency fixed, which is more amenable to theoretical modeling.

Committee:

Samir Bali (Advisor); Perry Rice (Committee Member); James Clemens (Committee Member)

Subjects:

Electromagnetics; Experiments; Optics; Physics; Quantum Physics

Keywords:

Electromagnetically Induced Transparency; Zeeman effect; anglular displacement; vapor cells; warm atoms; quantum optics

Popov, PiotrLIQUID CRYSTAL INTERFACES: EXPERIMENTS, SIMULATIONS AND BIOSENSORS.
PHD, Kent State University, 2015, College of Arts and Sciences / Department of Physics
Interfacial phenomena are ubiquitous and extremely important in various aspects of biological and industrial processes. For example, many liquid crystal applications start by alignment with a surface. The underlying mechanisms of the molecular organization of liquid crystals at an interface are still under intensive study and continue to be important to the display industry in order to develop better and/or new display technology. My dissertation research has been devoted to studying how complex liquid crystals can be guided to organize at an interface, and to using my findings to develop practical applications. Specifically, I have been working on developing biosensors using liquid-crystal/surfactant/lipid/protein interactions as well as the alignment of low-symmetry liquid crystals for potential new display and optomechanical applications. The biotechnology industry needs better ways of sensing biomaterials and identifying various nanoscale events at biological interfaces and in aqueous solutions. Sensors in which the recognition material is a liquid crystal naturally connects the existing knowledge and experience of the display and biotechnology industries together with surface and soft matter sciences. This dissertation thus mainly focuses on the delicate phenomena that happen at liquid interfaces. In the introduction, I start by defining the interface and discuss its structure and the relevant interfacial forces. I then introduce the general characteristics of biosensors and, in particular, describe the design of biosensors that employ liquid crystal/aqueous solution interfaces. I further describe the basic properties of liquid crystal materials that are relevant for liquid crystal-based biosensing applications. In CHAPTER 2, I describe the simulation methods and experimental techniques used in this dissertation. In CHAPTER 3 and CHAPTER 4, I present my computer simulation work. CHAPTER 3 presents insight of how liquid crystal molecules are aligned by hydrocarbon surfaces at the atomic level. I show that the vertical alignment of a rod-like liquid crystal molecule first requires its insertion into the alignment layer. In CHAPTER 4, I investigate the Brownian behavior of a tracer molecule at an oil/water interface and explain the experimentally-observed anomaly of its increased mobility. Following my molecular dynamics simulation studies of liquid interfaces, I continue my work in CHAPTER 5 with experimental research. I employ the high sensitivity of liquid crystal alignment to the presence of amphiphiles adsorbed to the liquid crystal surface from water for potential biosensor applications. I propose a more accurate method of sensing using circular polarization and spectrophotometry. In CHAPTER 6, I investigate if cholesteric and smectic liquid crystals can potentially offer new modes of biosensing. In CHAPTER 7, I describe preliminary results toward constructing a liquid crystal biosensor platform with capabilities of specific sensitivity using proteins and antibodies. Finally in CHAPTER 8, I summarize the findings of my studies and research and suggest possible future experiments to further advance our knowledge in interfacial science for future applications.

Committee:

Elizabeth Mann (Committee Chair); Antal Jákli (Committee Co-Chair); Edgar Kooijman (Committee Member); Björn Lüssem (Committee Member); John Portman (Committee Member); Deng-Ke Yang (Committee Member)

Subjects:

Biophysics; Experiments; Molecules; Physical Chemistry; Physics

Keywords:

liquid crystal sensor, liquid crystals, fluid interfaces, liquid interfaces, liquid surfaces, biosensor, molecular dynamics simulation

Bodamer Scarbro, Betsy LThe Physiological and Behavioral Responses of Yellow Perch to Hypoxia
Doctor of Philosophy, University of Toledo, 2014, College of Natural Sciences and Mathematics
Yellow Perch within Lake Erie's Central Basin must contend with the development of hypolimnetic hypoxia, which generally occurs August - October and reaches thicknesses of up to 8 meters off the lake bottom. Since Yellow Perch are primarily demersal benthivores, large portions of their primary habitat becomes unsuitable during hypoxic events. Field studies have shown that while Yellow Perch largely avoid hypoxia, they continue to forage for benthic prey despite hypoxic conditions. Little is known about the fine-scale behavioral changes of Yellow Perch during hypoxia, or the physiological consequences of hypoxic foraging. In controlled laboratory experiments, I analyzed the behavioral changes of Yellow Perch under simulated hypolimnetic hypoxia, and determined the physiological response of Yellow Perch to hypoxic exposure by measuring the response of a hypoxia-responsive protein, Hypoxic Inducible Factor-1-alpha (HIF-1a). Yellow Perch were subjected to normoxic (~8 mg DO/L), moderate hypoxic (~4 mg DO/L) or severe hypoxic (~2 mg DO/L) dissolved oxygen concentrations for durations of up to 8 hours, followed by a 40-hour normoxic recovery period. Baseline HIF-1a levels were detected in Yellow Perch liver tissues under normoxic conditions, and increased significantly after two hours of hypoxic exposure. HIF-1a peaked at 2 and 4 hours of hypoxic exposure under severe and moderate hypoxic conditions, respectively, but returned to levels similar to normoxic treatments by 8 hours of exposure. These results suggest Yellow Perch are well adapted to hypoxic conditions and that a direct negative feedback mechanism may aide survival under prolonged hypoxia. In order to observe the behavioral changes of Yellow Perch in stratified hypoxic conditions, I designed and constructed two experimental tank systems that simulated hypoxic conditions characteristic of temperate freshwater lakes. Using these systems, two behavioral experiments were conducted examining changes in behavior and consumption of Yellow Perch subjected to various thicknesses of hypolimnetic hypoxia. While the number of hypolimnetic forays did not differ between hypoxic and normoxic treatments, dive duration decreased significantly during hypoxia, resulting in less time total time in the hypolimnion. Consumption did not significantly decrease until hypoxic thickness reached 4.0 meters. These findings suggest that the ability of Yellow Perch to forage benthically is not greatly affected by hypoxia less than 2.6 meters in thickness; however, increasing hypoxic thickness likely decreases the energetic gain of benthic foraging, driving horizontal shifts in Yellow Perch populations to areas where hypoxia is thinner (< 2.6 m). Increases in the duration or spatial extent of hypoxia resulting from forecasted global climate conditions are likely to lead to further changes in community distributions, increased competition, and altered trophic interactions.

Committee:

Thomas Bridgeman, Ph.D. (Advisor); Christine Mayer, Ph.D. (Committee Member); W. Von Sigler, Ph.D. (Committee Member); Randall Ruch, Ph.D. (Committee Member); Jessica Head, Ph.D. (Committee Member)

Subjects:

Aquatic Sciences; Behavioral Sciences; Biology; Experiments; Freshwater Ecology; Limnology; Molecular Biology; Physiology

Keywords:

hypoxia; yellow perch, perca flavescens; stratification, Hypoxia Inducible Factor - HIF; fish behavior; Lake Erie

Wang, ShiyiEngineering Electromagnetic Wave Properties Using Subwavelength Antennas Structures
Doctor of Philosophy (Ph.D.), University of Dayton, 2015, Electro-Optics
With extraordinary properties, generation of complex electromagnetic field based on novel subwavelength antennas structures has attracted great attentions in many areas of modern nano science and technology, such as compact RF sensors, micro-wave receivers and nano-antenna-based optical/IR devices. This dissertation is mainly composed of two parts. For the first part, the idea of plasmonic localization in optical range is transferred and utilized for generating confined fields with high enhancement in RF range. A subwavelength modified bowtie antenna in RF range is designed for generating strong broadband field enhancement in its extended feed gap. The strongly enhanced RF field within the gap can be applied to directly modulate guided optical wave propagating in a waveguide, which enables to realize indirect RF signal sensing through photonic methods. Systematic exploration for modified bowtie antennas and its substrate effect has been given in this part. In the second part, the RF antenna design idea is extended to infrared and optical range based on antenna scaling theory specific for this spectrum. Both transmission and reflection types of metasurface structures have been designed and proposed to obtain optical needle field with a flat-top longitudinal intensity of depth of focus 5λ. With fine adjustment of different nano-antenna structures, both of the metasurfaces enable to generate complex vectorial field with spatial radial polarization, whose amplitude modulation range covers 0.07 to 1 with binary phase control. Then the scattered field can be tightly focused by a high numerical aperture (NA) lens in order to generate longitudinally polarized flat-top field along propagation direction. By exploring the subwavelength antennas’ mechanism and connections between different frequency regions, this dissertation is expected to provide general guidance for design and characterization of next-generation subwavelength antennas structures with extraordinary electromagnetic wave properties.

Committee:

Qiwen Zhan, PhD (Committee Chair); Partha Banerjee, PhD (Committee Member); Andrew Sarangan, PhD (Committee Member); Imad Agha, PhD (Committee Member)

Subjects:

Electromagnetics; Engineering; Experiments; Nanoscience; Nanotechnology; Optics

Keywords:

Subwavelength antennas; vectorial light; meta-surface; nano structures; full wave control; optical needle field

Liyanage, Geethika KaushalyaInfrared Emitting PbS Nanocrystals through Matrix Encapsulation
Master of Science (MS), Bowling Green State University, 2014, Physics
Colloidal semiconductor nanocrystals are becoming widely used materials in developing high performing light emitting devices in the Infrared region. The ability of tuning their properties at the colloidal stage and easy-low-cost processing of these Quantum Dot solutions in to nanocrystal solid devices makes them a perfect candidate in the device engineering process. One of the main challenges that present methods of making Infrared emitting thin film devices face is that both quantum yield efficiency and stability is compromised when processing them from colloidal stage to the solid state. The proposed method provides a better solution to this problem allowing a better assembly of Infrared emitting PbS nanocrystals encapsulated into an all inorganic matrix of wide band gap CdS. The newly proposed Semiconductor Matrix Encapsulation Nanocrystal Array (SMENA) method provides a better passivation in the PbS surfaces which can be optimized to reduce the non-radiative exciton decaying processes preserving the emission characteristics of the film. Due to the strong localization of the electrical charges, the films fabricated using modified SMENA method shows a bright emission yield compared to the current reported techniques. In addition to a high emission quantum yield, fabricated films exhibit excellent thermal and chemical stability, which avails their integration into solid state IR emitting technologies.

Committee:

Mikhail Zamkov (Advisor); Haowen Xi (Committee Member); Liangfeng Sun (Committee Member)

Subjects:

Chemical Engineering; Chemistry; Condensed Matter Physics; Engineering; Experiments; Materials Science; Nanoscience; Nanotechnology; Physics

Keywords:

nanomaterials; Lead sulfide; colloidal quantum dots; inorganic matrix; time-resolved fluorescence; quantum yield; Infrared materials; Matrix encapsulation

Borshch, VolodymyrNanosecond Electric Modification of Order Parameters
PHD, Kent State University, 2014, College of Arts and Sciences / Department of Chemical Physics
In this Dissertation, we study a nanosecond electro-optic response of a nematic liquid crystal in a geometry where an applied electric field E modifies the tensor order parameter but does not change the orientation of the optic axis (director ). We use nematics with negative dielectric anisotropy with the electric field applied perpendicularly to . The field changes the dielectric tensor at optical frequencies (optic tensor), due to the following mechanisms: (a) nanosecond creation of biaxial orientational order; (b) uniaxial modification of the orientational order that occurs over the timescales of tens of nanoseconds, and (c) quenching of director fluctuations with a wide range of characteristic times up to milliseconds. We develop a model to describe the dynamics of all three mechanisms. We design the experimental conditions to selectively suppress the contributions from the quenching of director fluctuations (c) and from the biaxial order effect (a) and thus, separate the contributions of the three mechanisms in the electro-optic response. As a result, the experimental data can be well fitted with the model parameters. The analysis provides a rather detailed physical picture of how the liquid crystal responds to a strong electric field, E ~ 108 V/m, on a timescale of nanoseconds. This work provides a useful guide in the current search of the biaxial nematic phase. Namely, the temperature dependence of the biaxial susceptibility allows one to estimate the temperature of the potential uniaxial-to-biaxial phase transition. An analysis of the quenching of director fluctuations indicates that on a timescale of nanoseconds, the classic model with constant viscoelastic material parameters might reach its limit of validity. The effect of nanosecond electric modification of the order parameter (NEMOP) can be used in applications in which one needs to achieve ultrafast (nanosecond) changes of optical characteristics, such as birefringence.

Committee:

Oleg Lavrentovich, DSc (Advisor); Sergij Shiyanovskii, DSc (Advisor)

Subjects:

Condensed Matter Physics; Experiments; Materials Science; Optics; Physics

Keywords:

Liquid Crystals; electro-optics; nanoseconds; Liquid Crystal Displays; dielectric anisotropy; nematic; dynamics; ultrafast switching; soft matter;uniaxial; biaxial; order parameter; fluctuations; birefringence;

Saks, Jeremy M.Demographic Congruency, Advertisements, and Television Shows: The Effect of Advertisement Viewing on Television Show Evaluation
Master of Science (MS), Ohio University, 2013, Journalism (Communication)
This thesis examines demographic congruency between television shows and advertisements and the effects that it has on program evaluation. Two groups of college- aged participants watched the same popular television show for their age group but some saw commercials targeted at them while others saw advertisements for products and services for elderly people. Theoretically based on Mandler's discrepancy/evaluation theory, results showed that individuals exposed to demographically incongruent advertisements explicitly evaluated the television show less favorably than those that saw congruent commercials. Additionally, an implicit associations test found marginally significant and contrasting results where the demographically incongruent advertisements led to a higher liking among those who viewed them along with the show. The results, as well as potential explanations, are discussed.

Committee:

Carson Wagner, PhD (Committee Chair); Jatin Srivastava, PhD (Committee Member); Hans Meyer, PhD (Committee Member)

Subjects:

Communication; Experimental Psychology; Experiments; Journalism; Marketing; Mass Communications; Mass Media; Psychology; Social Psychology

Keywords:

television; advertising; demographics; congruency; incongruency; experiment; Mandler; expectancy; disconfirmation

Hahn, Casey BernardDesign and Validation of the New Jet Facility and Anechoic Chamber
Master of Science, The Ohio State University, 2011, Mechanical Engineering

The jet facility and anechoic chamber at the Gas Dynamics and Turbulence Laboratory (GDTL) at The Ohio State University have been redesigned and rebuilt to significantly improve their capabilities. The new jet facility is capable of jets of 2-inch diameter—twice the size of the old jets. The new and much larger anechoic chamber can handle the larger jet and enables the measurements of shock noise generated by the jet of tactical aircraft. Free-field qualification requirements of ISO 3745 standard are met, and the chamber has a cutoff frequency of 160 Hz. A few improvements were incorporated into the new facility including thicker, acoustically-treated walls and an acoustically transparent grating floor above the floor anechoic wedges. Tests showed that very minor variations in the spectra are introduced by the grating floor panels.

Two additional microphones were added to the new facility with three within the upstream region of the acoustic field (a maximum polar angle of 130° compared to the maximum of 90° of the old facility). The radial distances of the microphones were increased, and far-field tests show that the microphones are safely within the far-field of 1-inch and 1.5-inch jets. For a 2-inch jet, some microphones are likely within the transition region of the acoustic field but could be moved farther outward to locate them within the far-field, as there is more room within the chamber. The stagnation chamber diameter was increased from 3.068 inches to 5.047 inches to handle the larger mass flow rate of a 2-inch jet. Initially, spectra suffered from narrowband cavity tones generated by ports upstream. The ports were modified, and a second perforated plate was added to eliminate these tones.

Acoustic data of the new and old jets are compared, and some minor differences in the high frequency content of the spectra are found. Early guesses point to internal rig noise created by flow through the second perforated plate. Work will continue to remove these differences. Finally, PIV results of the old and new jets are compared. The Mach number decay and spreading rates of a new Mach 0.9 jet compare well to an old Mach 0.9 jet. The old Mach 0.9 jets had slightly lower levels of turbulent kinetic energy. A new Mach 1.3 jet compares well with an old Mach 1.3 jet all these statistics.

Committee:

Mo Samimy, PhD (Advisor); Datta Gaitonde, PhD (Committee Member)

Subjects:

Acoustics; Aerospace Engineering; Engineering; Experiments; Fluid Dynamics; Mechanical Engineering

Keywords:

jet facility; anechoic chamber; aeroacoustics

Kalinoski, Zachary T.Error Management Training: Further Tests Of Mediation And Moderation
Master of Science (MS), Wright State University, 2009, Human Factors and Industrial/Organizational Psychology MS
This study investigated an alternative training approach that would improve transfer performance scores above traditional training approaches. Specifically, error-management training was proposed to help trainees learn complex tasks, as opposed to error-avoidant training approaches, which sought to give trainees step-by-step protocols for learning that would minimize the occurrence of errors during training. This study was designed to examine the effects of training type on transfer performance and transfer errors, as well as the effects of meta-cognition, emotion control and cognitive appraisals as mediators of the training type-performance relationship. A third issue of this study investigated the personality-training type interactions from a situation strength perspective. Participants (N = 181) from a Midwestern university completed four training trials and two transfer trials of a computerized version of a class scheduling task and completed surveys of relevant constructs. Results revealed that training type did not have an effect on transfer performance or errors, training type did not predict meta-cognition, emotion control and challenge appraisals, but did predict threat appraisals. Finally, personality did not have a main effect on performance, nor did it interact with training type. The relative contributions of this study was the effects of training type on cognitive appraisals (threat in particular) and its relevance for future theoretical frameworks of error management training research, the effects of training type on error attitudes and error attitude effects on performance. Previous operationializations of error management training also may not be as clear-cut as once thought.

Committee:

Debra Steele-Johnson, PhD (Committee Chair); Nathan Bowling, PhD (Committee Member); Dragana Claflin, PhD (Committee Member)

Subjects:

Behaviorial Sciences; Experiments; Occupational Psychology; Organizational Behavior; Psychology

Keywords:

error-management training; training; performance; cognitive appraisals; meta-cognition; emotion control; perfectionism; optimism; errors

Nawarange, Amruta V.Optical Emission Spectroscopy during Sputter Deposition of CdTe Solar Cells and CuTe-Based Back Contacts
Doctor of Philosophy, University of Toledo, 2011, Physics

In this dissertation sputtering processes are studied in detail through optical emission spectroscopy. In order to extract plasma parameters, experimental data and simulations were matched together. We could extract excitation temperatures, vibrational temperatures and rotational temperatures of the plasmas. To explain the simulations and to understand the different mechanisms involved in the sputtering plasmas, relevant aspects of atomic spectroscopy and molecular spectroscopy are reviewed here. A mixture of argon and nitrogen gas was used to sputter a CuxTe target by RF magnetron sputtering. The emission data were then studied as a function of deposition pressure and RF power. These data show many non equilibrium aspects of the plasma; however, in most cases the data are consistent with energy distributions of the rotational, vibrational, and electronic systems that can be characterized individually by distinct temperatures.

We have also used sputter deposition of CuxTe thin-film layers instead of our standard Cu/Au metal layers for back contacts to look for an improved back contact. We prepared three different compositions of CuxTe target material and studied the properties of sputtered films using X-Ray Diffraction (XRD), Energy Dispersive X-Ray Spectroscopy (EDS), Scanning Electron Microscopy (SEM) and Hall measurements. At optimized deposition conditions for Cu2Te target sputtered films (2 nm thickness and 20 minutes annealing in vacuum) as determined from the thin-film properties, we sputtered this layer onto the back surface of the CdTe of the cell structure. We achieved efficiencies of 13.1% using Cu2Te target sputtered films followed by Au which is very close to our best efficiency achieved with Cu/Au contacts.

Committee:

Alvin Compaan, PhD (Advisor); Alvin Compaan, PhD (Committee Chair); Brian Bagley, PhD (Committee Member); Randall Ellingson, PhD (Committee Member); Sanjay Khare, PhD (Committee Member); Dean Giolando, PhD (Committee Member)

Subjects:

Alternative Energy; Condensed Matter Physics; Experiments; Materials Science; Molecular Physics; Physics; Plasma Physics; Solid State Physics; Theoretical Physics

Keywords:

OES

Garimella, Venkata Naga RavikanthExhaust Emissions Analysis for Ultra Low Sulfur Diesel and Biodiesel Garbage Trucks
Master of Science in Civil Engineering, University of Toledo, 2010, Civil Engineering
The main objective of this experimental thesis is to study the exhaust emissions of in-use garbage trucks for different idling modes fuelled with alternate fuels. The emission concentrations of carbon monoxide, sulfur dioxide, oxides of nitrogen (NO, NO2, and NOX), and carbon dioxide were examined with respect to engine parameters such as fuel temperature, coolant temperature and percent fuel. A Testo350 XL portable emission monitoring instrument was used to collect second by second data for the pollutants. Performance of engine parameters was also monitored simultaneously using on-board diagnostic (OBD) software. The tail pipe emissions from Ultra-Low Sulfur Diesel (ULSD) are compared with emissions from biodiesel blends. Hotter engines produced lower emissions compared to colder engines for all fuel blends and vehicle makes. Significant reductions in emission concentrations were observed due to the inspection and maintenance programs. The performance of biodiesel blends in reducing emission concentrations of pollutants across different vehicle makes was found to be inconsistent. A comprehensive study on various vehicle, fuel and operating parameters that effect the exhaust emission concentrations was conducted to find an alternative to ULSD.

Committee:

Ashok Kumar, PhD (Committee Chair); Brian Randolph, PhD (Committee Member); Dong-Shik Kim, PhD (Committee Member)

Subjects:

Alternative Energy; Automotive Engineering; Civil Engineering; Environmental Engineering; Environmental Health; Environmental Science; Environmental Studies; Experiments; Sustainability; Transportation; Urban Planning

Keywords:

biodiesel; ultra low sulfur diesel; diesel; emission; exhaust; garbage truck; portable emission; blends; Idle engine; Alternative fuels; fuel

Passero, ThomasUsing popular culture to teach the community college business curriculum: A comparative study
Doctor of Philosophy, University of Toledo, 2011, Higher Education
This study addressed a need for comprehensive quantitative empirical studies to determine the effectiveness of using popular culture media as a teaching technique. A quasi-experimental design was implemented to examine whether a group of community college students taking a first-semester introduction to business course who were exposed to a teaching method incorporating popular culture media (Treatment Group) would have increased levels of knowledge and stronger preferences toward this method versus a group of students taking the same course who were not exposed to this teaching style (Control Group). Specifically, this study examined: (1) Do differences exist relative to student learning; (2) Do differences exist relative to perceived student comprehension; (3) Do differences exist relative to student semester retention; (4) Do differences exist relative to student semester attendance; (5) Do differences exist relative to student interest in the discipline of business; (6) Do differences exist relative to student’s interest in taking additional business courses; (7) Do differences exist relative to student satisfaction; (8) Do differences exist relative to student satisfaction between Millennial students and non-Millennial student. The 143 students taking part in the study comprised six intact groups, meaning they selected the days and times of the sections available that appealed to them (non-random samples). Without the students’ knowledge, the researcher/instructor arbitrarily selected three sections as the Treatment Groups and three as the Control Groups. Throughout the semester, general business concepts from the course textbook were taught to the Treatment Group using films, television shows, comic strips, and music. The Control Group were taught the same concepts but without the use of any popular culture media. Participants completed Pre-Delivery and Post-Delivery attitudinal questionnaires and took five multiple-choice exams during term. The fit of survey and exam data were tested using the Rasch model, with further hypotheses testing accomplished with Independent t’s, Chi-square cross-tabulations, and dependent paired samples. The analyses showed no significance between the groups receiving different teaching methods on knowledge, retention, or attendance. However, there were statistically significant differences on perceived knowledge, interest in the business major, interest in taking additional business courses, and course satisfaction for both the Treatment Group and Control Group favoring the popular culture-enhanced methodology. Regarding generational attitudes this alternative teaching method, both the Millennial and Non-millennial sub-groups strongly favored the popular culture techniques over the traditional ones. Implications for students and instructors are discussed, along with suggestions for future research.

Committee:

David Meabon, PhD (Committee Chair); Mary Ellen Edwards, PhD (Committee Member); Angela M. Nelson, PhD (Committee Member); Gregory E. Stone, PhD (Committee Member)

Subjects:

Adult Education; Business Education; Education; Educational Tests and Measurements; Experiments; Higher Education; Inservice Training; Instructional Design; Mass Media; Pedagogy; Teacher Education; Teaching

Keywords:

teaching techniques: instructional methodology; popular culture; quantitative study; quasi-experimental; Rasch; community college; millennial; survey; media; business education; empirical study

Kuznetsov, Nikita AleksandrovichPostural Sway Complexity in Healthy Older Adults and Individuals with Asthma
PhD, University of Cincinnati, 2013, Arts and Sciences: Psychology
The goal of the dissertation was to examine the loss of complexity hypothesis in context of postural control of healthy community-dwelling older adults (over 65) and younger adults with asthma (under 30). The loss of complexity provides a dynamical systems framework for understanding the relation between adaptability and complexity of a physiological (or behavioral) system and the dynamics of the resulting output from this system. It predicts that with the simplification of the system due to aging and disease (e.g., loss of functional degrees of freedom or coupling between them), the outputs measured from the system deviate from healthy irregular dynamics (characterized by 1/f-like fluctuations or intermediate entropy values) toward more regular or more irregular dynamics. I examined these ideas using the center of pressure (COP) as a variable to quantify postural control complexity in four experiments that emphasized the stabilizing capacity of the postural control system. In the first three studies, participants were required to maintain their COP on a stationary target while seeing visual feedback about their COP in real time. Two studies on aging demonstrated that older adults were not always more regular than younger adults as quantified by sample entropy. Older adults in Experiment 1 typically had more regular and more variable COP fluctuations in the feedback condition, but did not differ in COP regularity from younger adults in the no-feedback condition. Older adults with higher Berg balance scale scores also had more irregular ML COP dynamics only in the feedback condition. In the second aging experiment there were no age differences in COP regularity either when standing with equally distributed pressure or leaning more on left or right foot. The two studies on asthma also demonstrated a similar task-dependence of COP regularity differences. People with asthma were more regular in their AP COP than the controls in both feedback and no-feedback conditions of Experiment 3. These differences were accounted for by the group differences in static posture and anxiety sensitivity. However, Experiment 4 revealed that postural control differences between the asthmatics and controls were more pronounced when standing on a narrow base of support as opposed to full support (which were not accounted by anxiety sensitivity differences). In all of the experiments, I also calculated the degree of mathematical coupling between breathing and COP to quantify the level of integration between the respiratory and postural control synergies. None of the studies showed any systematic group differences on this metric, indicating that the level of integration between the respiratory and postural systems was not altered. Overall, the results suggest that the loss of complexity hypothesis requires consideration task constraints in addition to the typically emphasized organismic constraints.

Committee:

Michael Riley, Ph.D. (Committee Chair); Michael Richardson, Ph.D. (Committee Member); Kevin Shockley, Ph.D. (Committee Member)

Subjects:

Experiments

Keywords:

postural control;complexity;aging;asthma

Rodabaugh, Hannah MarieA Flower Opened in the Stinking
Master of Arts, Miami University, 2010, English
This manuscript reflects a poetic exploration into various approaches to problems of defining wisdom within sacred texts, as well as experimentation with sound, language, and grammar. It is designed to be or explain some of the multi-faceted ways in which inspiration comes to us. Like the Hindu existential bodies, it is divided into four sections; each section sets up a problem that the remaining poems seek to rectify, or at least neutralize by the end of the segment. It is told in a wide range of styles (letters, songs, free verse, and rhyme) to reflect this multi-faceted approach. It offers varying tones for the same reason. Similar to Aristotelian concepts of theatre, where an audience is purged of negative emotions by watching a character consumed by them, this work, often humorously, evokes a sense of what not to do as much as it offers any sense of friendly wisdom.

Committee:

Cathy Wagner (Committee Chair); Keith Tuma (Committee Member); cris cheek (Committee Member)

Subjects:

American Literature; Composition; English literature; Experiments; Fine Arts

Keywords:

Poetry; experimental writing; spiritual texts; religious traditions

Sacco, Donald F.Facial Attractiveness and Helping Behavior Attributions: Attractive and Unattractive Persons Are Perceived of as Unhelpful
Doctor of Philosophy, Miami University, 2010, Psychology
Three studies explored the relationship between facial attractiveness and attributions of prosocial behavior. On a between-subjects (Study 1) and within-subjects (Study 2) basis, participants were shown images of targets possessing low, average and high facial attractiveness and were asked to indicate their impressions of how helpful these targets should be as well as how helpful these targets actually are. In both studies, attractive and unattractive targets were seen as actually engaging is less helping behavior than targets of average attractiveness; participants also perceived a consistent gap in unattractive and attractive targets’ actual helping behavior compared to how much they should help. Study 3 extended these findings by indicating that attractive and average targets are seen as more capable of helping than unattractive targets whereas both attractive and unattractive targets are seen as less willing to help than targets of neutral attractiveness. Perceptions of both attractive and unattractive targets’ willingness to help mediated perceptions of how much these targets actually help. Perceptions of unattractive targets willingness to help also mediated perceptions of how much these targets should help. Finally, perceptions of unattractive targets’ capability of helping mediated perceptions of how much they actually help and should help.

Committee:

Kurt Hugenberg, PhD (Committee Chair); Heather Claypool, PhD (Committee Member); Amanda Diekman, PhD (Committee Member); Timothy Heath, PhD (Committee Member); Gary Stasser, PhD (Committee Member)

Subjects:

Behaviorial Sciences; Experiments; Psychology; Social Psychology

Keywords:

physical attractiveness; face perception; prosocial behavior; stereotyping; attribution theory

Hsiao, E-LingThe Effectiveness of Worked Examples Associated with Presentation Format and Prior Knowledge: A Web-based Experiment
Doctor of Philosophy (PhD), Ohio University, 2010, Curriculum and Instruction Instructional Technology (Education)
The aim of this study is to explore whether presentation format and prior knowledge affect the effectiveness of worked examples. The experiment was conducted through a specially designed online instrument. A 2X2X3 factorial before-and-after design was conducted. Three-way ANOVA was employed for data analysis. The result showed first, that prior knowledge, gender and class year had some impacts on the effectiveness of worked examples, so individual differences needs to be considered while designing worked example instruction. Second, the expert reversal effect (Kalyuga et al, 2001) was confirmed by one of findings in the study. When worked example instruction was provided, the higher prior knowledge level groups reported lower cognitive load by viewing the text-only presentation format; in contrast, the low prior knowledge level group reported lower cognitive load by viewing the text-plus-graphic presentation format. It indicated novices might need more detailed guidance in worked example instruction. Third, the study discovered that the low prior knowledge level group reported lower cognitive load by viewing the text-plus-graphic worked examples instead of text-only worked examples. It indicated that integrating text and graphics in worked examples might help novice learn better. Lastly, the findings of the study showed that high prior knowledge level group performed better on the posttest by using worked examples than general statement. The study indicated that worked examples may not only benefit novices as previous studies addressed (Crissman, 2006; Kalyuga, et al., 1998), it may also work for experts.

Committee:

David R. Moore, PhD (Committee Chair); Teresa Franklin, PhD (Committee Member); George Johanson, EdD (Committee Member); Ginger Weade, PhD (Committee Member)

Subjects:

Education; Educational Theory; Experiments; Gender; Higher Education; Teaching; Technology

Keywords:

Worked Example Effect; Prior Knowledge; Presentation Format; Web-based Experiment; Cognitive Load Theory

Potrafka, Zepher BensonRetroarchaeography: A Comprehensive Guide for the Field and the Laboratory
Master of Fine Arts, The Ohio State University, 2010, Art
This thesis covers the science of retroarchaeography, explaining its relevance in the world as well as its development and current practice. It serves as an explanation of how and why I make art, and a guide for anyone who wishes to pursue the same lines of reasoning that tie my work together. The techniques, processes, and principles laid out in this text represent the best system I have found to share my experience of the world with others.

Committee:

Todd Slaughter (Advisor); Malcolm Cochran (Committee Member); Julie Field (Committee Member)

Subjects:

American History; Ancient Civilizations; Archaeology; Art History; Environmental Science; Experiments; Fine Arts; Folklore; History; Museums

Keywords:

Retroarchaeography; art; science; archaeology; field guide; artifacts; museum

Gurney, Rebecca L.Stimulus Generalization to Different levels of Illumination in Paramecium caudatum
Doctor of Philosophy, University of Toledo, 2008, Psychology
This study was conducted to determine if paramecia (P. caudatum), unicellular organisms, could exhibit stimulus generalization as do mammals and other multicellular organisms. Paramecia were placed in a trough that was divided into two equal portions, one light and one dark, and were trained on a light-dark discrimination. They were rewarded for remaining in the half of the trough that was connected to the cathode of an electrical stimulator, as such cathode stimulation had been shown to be attractive to paramecia. For half of the paramecia, the cathode was connected to the light half of the trough during training. During test, light stimuli which varied in brightness were substituted for the original light stimulus to determine if the paramecia would generalize the training information to the test stimuli. The dark side of the trough remained at a fixed illumination level. For the test phase, the location of the “light side” was switched to the side of the trough opposite to that used during training. The same procedure was carried out for the other half of the subjects, except that, for these paramecia, dark side was associated with the cathode during training. During test the “dark side” was varied in brightness and the “light side” remained at a fixed illumination level. The current experiment did not provide strong evidence that paramecia do generalize, at least under the conditions of this study; however it replicated the finding that paramecia prefer the side that was paired with the cathode electrical stimulation.

Committee:

Harvard Armus, PhD (Advisor); Henry Heffner, PhD (Committee Member); Kamala London, PhD (Committee Member); John Jasper, PhD (Committee Member); James Klein, JD (Committee Member)

Subjects:

Ecology; Experiments; Psychology

Keywords:

Paramecia; Stimulus Generalization; Learning

Beam, Michael A.Personalized News: How Filters Shape Online News Reading Behavior
Doctor of Philosophy, The Ohio State University, 2011, Communication

The evolution and diffusion of communication technology has consistently changed interactions between members of the public sphere in forming public opinion. Some democratic scholars have worried recent developments in personalization technologies will degrade public opinion formation. They worry that personalized news allows citizens to only pay attention to news coming from their preferred political perspective and may isolate them from challenging perspectives. Empirical research has shown people with access to more highly selective information technology demonstrate increases in both selectivity and incidental exposure to diverse perspectives.

This dissertation focuses on these behavioral and attitudinal outcomes of using personalized news technologies. Dual-processing theories of information provide the foundation for analyzing opinion formation within the bounded rationality model of public opinion. Personalized news technologies are hypothesized to increase the amount of news exposure and elaboration through increased personal relevance.

Two studies test these broad hypotheses. First, results from a national random sample of adults show users of personalized web portals are more likely to engage in increased news viewing both online and offline. No differences in preference for perspective sharing or challenging sources of news is found between personalized portal users and non-users. Next, results from an online experiment of Ohio adult Internet users show an increase in time spent reading news articles in personalized news portals compared with a generic portal. An interaction between using customized news portals with source recommendations based off of explicit user preferences and increased time spent reading per news article is found on news elaboration. No differences in news elaboration are found in other personalized news designs including implicitly recommended news sources based on user profile information and only showing users recommended stories. The implications of these results are discussed in terms of the public opinion debate about new communication technologies, selective exposure research, information processing research, and personalized information system design.

Committee:

Gerald M. Kosicki, PhD (Advisor); David R. Ewoldsen, PhD (Committee Member); R. Kelly Garrett, PhD (Committee Member); Andrew F. Hayes, PhD (Committee Member)

Subjects:

Behavioral Sciences; Behaviorial Sciences; Communication; Experiments; Information Systems; Information Technology; Journalism; Mass Communications; Political Science

Keywords:

Internet; personalized; personalization; news; public opinion; politics; election; selective exposure; information processing; portal; web; communication; elaboration

von Deak, Dieter G.Heteroatom-containing Carbon Nanostructures as Oxygen Reduction Electrocatalysts for PEM and Direct Methanol Fuel Cells
Doctor of Philosophy, The Ohio State University, 2011, Chemical and Biomolecular Engineering
The main goal of this work was to undertake a fundamental investigation of precious metal-free carbon catalysts nano-structure modification to enable their use as oxygen reduction reaction (ORR) catalysts in proton exchange membrane (PEM) fuel cells. The sluggish ORR is accelerated by fiscally prohibitive loadings of Pt catalyst. The expense and availability of platinum motivate the development of non-precious metal carbon-nitroge-based ORR catalysts (CNx). The project targets the nature of oxygen reduction reaction active sites and exploring ways to create these sites by molecular tailoring of carbon nano-structures. CNx grown with phosphorous had a significant increase in the ORR active site density. CNx catalyst growth media was prepared by acetonitrile deposition over a Fe and P impregnated MgO. Rotating Ring Disk Electrode (RRDE) Activity and selectivity showed a significant increase in oxygen reduction current with CNx grown with less than a 1:1 molar ratio of P:Fe. Selectivity for the full reduction of dioxygen to water trended with increasing ORR activity for phosphorous grown CNx catalysts. Phosphorus growth altered the morphology of carbon-nitride graphite formed during pyrolysis. The role of the transition metal used to form non-noble metal electrochemical oxygen reduction CNx catalysts was investigated through sulfur and carbon monoxide treatments of the CNx and Pt/carbon electrocatalysts. The intent of poisoning was to show the existence of a non-iron containing electrocatalytic active site in CNx. The sulfur treatment increased the overpotential on a platinum catalyst, but enhanced the current density of the CNx catalyst while leaving the CNx iron phase unchanged. CO in the present of oxygen was found to strongly adsorb to platinum and completely eliminate all oxygen reduction. Under identical conditions, CNx showed a displacement of oxygen due to CO and no oxygen reduction poisoning effect. This suggests that either iron-based active site is sulfur and CO tolerant or that this active site does not participate in the electrocatalytic reduction of oxygen in CNx catalysts. Density functional theory (DFT) calculations of small polycyclic aromatic hydrocarbons (PAHs) that have a similar electronic structure to carbon-nitride catalyst materials were preformed. A strong correlation between B3LYP method N 1s energies and experimental N 1s energies was established for the PAHs studied. Additionally, experimental ionization potentials that would correspond to electron donation trended strongly with the DFT adiabatic and vertical ionization potentials. The testing and setup of fuel cell test station was accomplished. Bench scale membrane electrode assemblies (MEAs) were fabricated cell and achieved comparable performance to a commercial MEA constructed from similar materials. A MEA was constructed with a CNx cathode and was found to have fuel cell performance of the same order of magnitude as other graphitic carbon-nitrogen catalysts heat-treated in the presence of a transition metal. Vulcan carbon and CNx catalysts were compared in accelerated carbon corrosion by examining the current of the electrochemically active surface species hydroquinone/quione with cyclic voltammetry after extended potential holds. CNx was found to be more corrosion resistant than Vulcan carbon that is the most commonly used support in fuel cell electrodes.

Committee:

Umit Ozkan, S (Advisor); David Wood, W (Committee Member); James Rathman, F (Committee Member)

Subjects:

Alternative Energy; Analytical Chemistry; Chemical Engineering; Chemistry; Energy; Engineering; Experiments

Keywords:

catalyst; PEM; fuel cell; oxygen reduction; carbon nitride; graphite; XPS; XAS; corrosion; TEM; phosphorus; sulfur; electrochemistry; RRDE

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