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Title: Design, Characterization and Analysis of Electrostatic Discharge (ESD) Protection Solutions in Emerging and Modern Technologies.
Creator: Liu, Wen, Liou, Juin, Yuan, Jiann-Shiun, Sundaram, Kalpathy, Shen, Zheng, Chen, Quanfang, University of Central Florida
Abstract / Description: Electrostatic Discharge (ESD) is a significant hazard to electronic components and systems. Based on a specific processing technology, a given circuit application requires a customized ESD consideration that includes the devices' operating voltage, leakage current, breakdown constraints, and footprint. As new technology nodes mature every 3-5 years, design of effective ESD protection solutions has become more and more challenging due to the narrowed design window, elevated electric field and...
Show moreElectrostatic Discharge (ESD) is a significant hazard to electronic components and systems. Based on a specific processing technology, a given circuit application requires a customized ESD consideration that includes the devices' operating voltage, leakage current, breakdown constraints, and footprint. As new technology nodes mature every 3-5 years, design of effective ESD protection solutions has become more and more challenging due to the narrowed design window, elevated electric field and current density, as well as new failure mechanisms that are not well understood. The endeavor of this research is to develop novel, effective and robust ESD protection solutions for both emerging technologies and modern complementary metal(-)oxide(-)semiconductor (CMOS) technologies.The Si nanowire field-effect transistors are projected by the International Technology Roadmap for Semiconductors as promising next-generation CMOS devices due to their superior DC and RF performances, as well as ease of fabrication in existing Silicon processing. Aiming at proposing ESD protection solutions for nanowire based circuits, the dimension parameters, fabrication process, and layout dependency of such devices under Human Body Mode (HBM) ESD stresses are studied experimentally in company with failure analysis revealing the failure mechanism induced by ESD. The findings, including design methodologies, failure mechanism, and technology comparisons should provide practical knowhow of the development of ESD protection schemes for the nanowire based integrated circuits. Organic thin-film transistors (OTFTs) are the basic elements for the emerging flexible, printable, large-area, and low-cost organic electronic circuits. Although there are plentiful studies focusing on the DC stress induced reliability degradation, the operation mechanism of OTFTs subject to ESD is not yet available in the literature and are urgently needed before the organic technology can be pushed into consumer market. In this work, the ESD operation mechanism of OTFT depending on gate biasing condition and dimension parameters are investigated by extensive characterization and thorough evaluation. The device degradation evolution and failure mechanism under ESD are also investigated by specially designed experiments. In addition to the exploration of ESD protection solutions in emerging technologies, efforts have also been placed in the design and analysis of a major ESD protection device, diode-triggered-silicon-controlled-rectifier (DTSCR), in modern CMOS technology (90nm bulk). On the one hand, a new type DTSCR having bi-directional conduction capability, optimized design window, high HBM robustness and low parasitic capacitance are developed utilizing the combination of a bi-directional silicon-controlled-rectifier and bi-directional diode strings. On the other hand, the HBM and Charged Device Mode (CDM) ESD robustness of DTSCRs using four typical layout topologies are compared and analyzed in terms of trigger voltage, holding voltage, failure current density, turn-on time, and overshoot voltage. The advantages and drawbacks of each layout are summarized and those offering the best overall performance are suggested at the end.
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Date Issued: 2012
Identifier: CFE0004571, ucf:49199
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004571

Title: Theoretical And Experimental Investigation Of The Cascading Nature Of Pressure-Swirl Atomization.
Creator: Choudhury, Pretam, Kumar, Ranganathan, Deng, Weiwei, Mansy, Hansen, University of Central Florida
Abstract / Description: Pressure swirl atomizers are commonly used in IC, aero-engines, and liquid propellant rocket combustion. Understanding the atomization process is important in order to enhance vaporization, mitigate soot formation, design of combustion chambers, and improve overall combustion efficiency. This work utilizes non-invasive techniques such as ultra -speed imaging, and Phase Doppler Particle Anemometry (PDPA) in order to investigate the cascade atomization process of pressure-swirl atomizers by...
Show morePressure swirl atomizers are commonly used in IC, aero-engines, and liquid propellant rocket combustion. Understanding the atomization process is important in order to enhance vaporization, mitigate soot formation, design of combustion chambers, and improve overall combustion efficiency. This work utilizes non-invasive techniques such as ultra -speed imaging, and Phase Doppler Particle Anemometry (PDPA) in order to investigate the cascade atomization process of pressure-swirl atomizers by examining swirling liquid film dynamics and the localized droplet characteristics of the resulting hollow cone spray. Specifically, experiments were conducted to examine these effects for three different nozzles with orifice diameters .3mm, .5mm, and .97mm. The ultra-speed imaging allowed for both visualization and interface tracking of the swirling conical film which emanated from each nozzle. Moreover, this allowed for the measurement of the radial fluctuations, film length, cone angle and maximum wavelength. Radial fluctuations are found to be maximum near the breakup or rupture of a swirling film. Film length decreases as Reynolds number increases. Cone angle increases until a critical Reynolds number is reached, beyond which it remains constant. A new approach to analyze the temporally unstable waves was developed and compared with the measured maximum wavelengths. The new approach incorporates the attenuation of a film thickness, as the radius of a conical film expands, with the classical dispersion relationship for an inviscid moving liquid film. This approach produces a new long wave solution which accurately matches the measured maximum wavelength swirling conical films generated from nozzles with the smallest orifice diameter. For the nozzle with the largest orifice diameter, the new long wave solution provides the upper bound limit, while the long wave solution for a constant film thickness provides the lower bound limit. These results indicate that temporal instability is the dominating mechanism which generates long Kelvin Helmholtz waves on the surface of a swirling liquid film. The PDPA was used to measure droplet size and velocity in both the near field and far field of the spray. For a constant Reynolds number, an increase in orifice diameter is shown to increase the overall diameter distribution of the spray. In addition, it was found that the probability of breakup, near the axis, decreases for the largest orifice diameter. This is in agreement with the cascading nature of atomization.
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Date Issued: 2015
Identifier: CFE0006030, ucf:51012
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006030

Title: Multi-Row Film Cooling Boundary Layers.
Creator: Natsui, Gregory, Kapat, Jayanta, Raghavan, Seetha, Vasu Sumathi, Subith, University of Central Florida
Abstract / Description: High fidelity measurements are necessary to validate existing and future turbulence models for the purpose of producing the next generation of more efficient gas turbines. The objective of the present study is to conduct several different measurements of multi-row film cooling arrays in order to better understand the physics involved with injection of coolant through multiple rows of discrete holes into a flat plate turbulent boundary layer. Adiabatic effectiveness distributions are measured...
Show moreHigh fidelity measurements are necessary to validate existing and future turbulence models for the purpose of producing the next generation of more efficient gas turbines. The objective of the present study is to conduct several different measurements of multi-row film cooling arrays in order to better understand the physics involved with injection of coolant through multiple rows of discrete holes into a flat plate turbulent boundary layer. Adiabatic effectiveness distributions are measured for several multi-row film cooling geometries. The geometries are designed with two different hole spacings and two different hole types to yield four total geometries. One of the four geometries tested for adiabatic effectiveness was selected for flowfield measurements. The wall and flowfield are studied with several testing techniques, including: particle image velocimetry, hot wire anemometry, pressure sensitive paint and discrete gas sampling.
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Date Issued: 2015
Identifier: CFE0005982, ucf:50776
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005982

Title: Digital Dissonance: Horror Cultures in the Age of Convergent Technologies.
Creator: Powell, Daniel, McDaniel, Rudy, Campbell, James, Brenckle, Martha, Arnzen, Michael, University of Central Florida
Abstract / Description: The first two decades of the new millennium have witnessed an abundance of change in the areas of textual production, digital communication, and our collective engagement with the Internet. This study explores these changes, which have yielded both positive and negative cultural and developmental outcomes, as products of digital dissonance. Dissonance is characterized by the disruptive consequences inherent in technology's incursion into the print publication cultures of the twentieth century...
Show moreThe first two decades of the new millennium have witnessed an abundance of change in the areas of textual production, digital communication, and our collective engagement with the Internet. This study explores these changes, which have yielded both positive and negative cultural and developmental outcomes, as products of digital dissonance. Dissonance is characterized by the disruptive consequences inherent in technology's incursion into the print publication cultures of the twentieth century, the explosion in social-media interaction that is changing the complexion of human contact, and our expanding reliance on the World Wide Web for negotiating commerce, culture, and communication.This study explores digital dissonance through the prism of an emerging literary subgenre called technohorror. Artists working in the area of technohorror are creating works that leverage the qualities of plausibility, mundanity, and surprise to tell important stories about how technology is altering the human experience in the twenty-first century. This study explores such subjects as paradigmatic changes in textual production methods, dynamic authorial hybridity, digital materiality in folklore studies, posthumanism, transhumanism, cognitive diminution, and physical degeneration as explored in works of technohorror.The work's rhetorical architecture includes elements of both theoretical and qualitative research. This project expands on City University of New York philosophy professor No(&)#235;l Carroll's definition of art-horror in developing a formal explanation of technohorror and then exploring that literary subgenre through the analysis of a series of contemporary texts and industry-related trends. The study also contains original interviews with active scholars, artists, editors, and librarians in the horror field to gain a variety of perspectives on these complicated subjects.
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Date Issued: 2017
Identifier: CFE0006642, ucf:51231
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006642

Title: X-ray Scattering Investigations of Metallic Thin Films.
Creator: Warren, Andrew, Coffey, Kevin, Sohn, Yongho, Suryanarayana, Challapalli, Heinrich, Helge, Barmak, Katayun, Toney, Michael, University of Central Florida
Abstract / Description: Nanometric thin films are used widely throughout various industries and for various applications. Metallic thin films, specifically, are relied upon extensively in the microelectronics industry, among others. For example, alloy thin films are being investigated for CMOS applications, tungsten films find uses as contacts and diffusion barriers, and copper is used often as interconnect material. Appropriate metrology methods must therefore be used to characterize the physical properties of...
Show moreNanometric thin films are used widely throughout various industries and for various applications. Metallic thin films, specifically, are relied upon extensively in the microelectronics industry, among others. For example, alloy thin films are being investigated for CMOS applications, tungsten films find uses as contacts and diffusion barriers, and copper is used often as interconnect material. Appropriate metrology methods must therefore be used to characterize the physical properties of these films. X-ray scattering experiments are well suited for the investigation of nano-scaled systems, and are the focus of this doctoral dissertation. Emphasis is placed on (1) phase identification of polycrystalline thin films, (2) the evaluation of the grain size and microstrain of metallic thin films by line profile analysis, and (3) the study of morphological evolution in solid/solid interfaces.To illustrate the continued relevance of x-ray diffraction for phase identification of simple binary alloy systems, Pt-Ru thin films, spanning the compositional range from pure Pt to pure Ru were investigated. In these experiments, a meta-stable extension of the HCP phase is observed in which the steepest change in the electronic work function coincides with a rapid change in the c/a ratio of the HCP phase.For grain size and microstrain analysis, established line profile methods are discussed in terms of Cu and W thin film analysis. Grain sizes obtained by x-ray diffraction are compared to transmission electron microscopy based analyses. Significant discrepancies between x-ray and electron microscopy are attributed to sub-grain misorientations arising from dislocation core spreading at the film/substrate interface. A novel "residual" full width half max parameter is introduced for examining the contribution of strain to x-ray peak broadening. The residual width is subsequently used to propose an empirical method of line profile analysis for thin films on substrates.X-ray reflectivity was used to study the evolution of interface roughness with annealing for a series of Cu thin films that were encapsulated in both SiO2 and Ta/SiO2. While all samples follow similar growth dynamics, notable differences in the roughness evolution with high temperature ex-situ annealing were observed. The annealing resulted in a smoothing of only one interface for the SiO2 encapsulated films, while neither interface of the Ta/SiO2 encapsulated films evolved significantly. The fact that only the upper Cu/SiO2 interface evolves is attributed to mechanical pinning of the lower interface to the rigid substrate. The lack of evolution of the Cu/Ta/SiO2 interface is consistent with the lower diffusivity expected of Cu in a Cu/Ta interface as compared to that in a Cu/SiO2 interface. The smoothing of the upper Cu/SiO2 interface qualitatively follows that expected for capillarity driven surface diffusion but with notable quantitative deviation.
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Date Issued: 2013
Identifier: CFE0004770, ucf:49784
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004770

Title: Zora.
Creator: Tyrrell, Genevieve, Roney, Lisa, Rushin, Patrick, Scott, John, University of Central Florida
Abstract / Description: This mixed-media memoir uses a variety of forms from short epigrammatic essays to straightforward stories and graphic narratives to explore the author's coming-of-age experiences augmented by chronic illness. Trying to succeed in the film industry, romance, and family situations, the young female narrator navigates the often unexpected or disappointing consequences of having an autonomic nervous system disorder. Relationships between conflicting identities emerge(-)between healthy versus sick...
Show moreThis mixed-media memoir uses a variety of forms from short epigrammatic essays to straightforward stories and graphic narratives to explore the author's coming-of-age experiences augmented by chronic illness. Trying to succeed in the film industry, romance, and family situations, the young female narrator navigates the often unexpected or disappointing consequences of having an autonomic nervous system disorder. Relationships between conflicting identities emerge(-)between healthy versus sick self, projected/envisioned versus actual self, and tough versus vulnerable self(-)as the narrator journeys toward a more complete and accepting self-understanding.
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Date Issued: 2013
Identifier: CFE0004763, ucf:49777
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004763

Title: E.A.I. Anxiety: Technopanic and Post-Human Potential.
Creator: Mandell, Zachary, Brenckle, Martha, Jones, Natasha, Scott, Blake, University of Central Florida
Abstract / Description: Robots have been a part of the imagination of Western culture for centuries. The possibility for automation and artificial life has inspired the curiosity of thinkers like Leonardo Da Vinci who once designed a mechanical knight. It wasn't until the 19th century that automated machinery has become realized. The confrontation between human and automation has inspired a fear, referred to as (")technopanic("), that has been exacerbated in tandem with the evolution of technology. This thesis seeks...
Show moreRobots have been a part of the imagination of Western culture for centuries. The possibility for automation and artificial life has inspired the curiosity of thinkers like Leonardo Da Vinci who once designed a mechanical knight. It wasn't until the 19th century that automated machinery has become realized. The confrontation between human and automation has inspired a fear, referred to as (")technopanic("), that has been exacerbated in tandem with the evolution of technology. This thesis seeks to discover the historical precedence for these fears. I explore three modes of knowledge (Philosophy, Economics, and Film Theory) to examine the agendas behind the messages on the topic of Artificial Life, specifically Robots. I then advocate for an alternative philosophy called Post-Humanism. I argue that what is needed to alleviate the fears and anxieties of Western culture is a shift in how humanity views itself and its relation to the natural world. By structuring my thesis in this way, I identify the roots of Western humanity's anthropocentric ontology first, explore the economic implications of automation second, analyze the cultural anticipations of artificial life in Western media third, and finally offer an alternative attitude and ethic as a way out of the pre-established judgments that do little to protect Western culture from E.A.I.
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Date Issued: 2018
Identifier: CFE0007049, ucf:52022
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007049

Title: MEASUREMENTS IN AIR-WATER BUBBLY FLOW THROUGH A VERTICAL NARROW HIGH-ASPECT RATIO CHANNEL.
Creator: Patrick, Benjamin, Kumar, Ranganathan, University of Central Florida
Abstract / Description: Two-Phase bubbly flows are encountered in a wide range of industrial applications, particularly where phase changes occur as seen in high performance heat exchangers and boiling reactors for power generation. These flows have been extensively studied in channels with circular geometries using air-water flows, though little data exists for flows through narrow rectangular channels. Measurements in thin geometries are particularly challenging since large bubbles bridge the gap, and it is...
Show moreTwo-Phase bubbly flows are encountered in a wide range of industrial applications, particularly where phase changes occur as seen in high performance heat exchangers and boiling reactors for power generation. These flows have been extensively studied in channels with circular geometries using air-water flows, though little data exists for flows through narrow rectangular channels. Measurements in thin geometries are particularly challenging since large bubbles bridge the gap, and it is difficult to compare point measurements with photographic techniques. The objective of this study is to explore the abilities of hot-film anemometry and high speed photography for taking measurements in a narrow vertical rectangular channel for a range of volume fractions, with particular attention on the narrow dimension. Hot-film anemometry (HFA) is a measurement technique originally developed for the measurement of fluid velocities, but has since been found to have applications for broader measurements in multiphase flow. With the sensor operating on the principle of heat loss, the method takes advantage of the differing abilities of the phases to transport heat, with each phase leaving its own signature in the signal response. The linchpin of this method lies in the ability to accurately distinguish between the two phases within the signal, and to execute this operation, various algorithms and techniques have been developed and used with some success for a wide range of flow conditions. This thesis is a study of the various methods of analysis such as amplitude threshold for triggering, and small slope threshold for finely tuning the edges of the bubble interactions, and demonstrates the capabilities of the hot-film sensor in a narrow rectangular vertical duct with a high aspect ratio. A vertical acrylic test section was fabricated for the purposes of this study, inset with a rectangular channel 38.1mm in width and 3.125mm in depth. Experiments were conducted for volume fractions ranging from 2% to 35%, which remained within the limits of the bubbly flow regime, but ranged from small uniform bubbles to larger bubbles coalescing into a transition regime. The hot-film signal was analyzed for void fraction, bubble speed, and bubble size. An in- depth study of the various methods of phase discrimination was performed and the effect of threshold selection was examined. High-speed video footage was taken in conjunction with the anemometer data for a detailed comparison between methods. The bubble speed was found to be in close agreement between the HFA and high-speed video, staying within 10% for volume fractions above 10%, but still remaining under a 30% difference for even as low as the 2% volume fraction, where measurements have been found to be historically difficult. The trends with volume fraction between the HFA and high-speed results were very similar. A correlation for narrow rectangular channels employing a simple drift flux model was found to compare with the void fraction data where appropriate. Good agreement was found between the methods using a hybrid phase discrimination technique for the HFA data for the void fraction and bubble speed results, with the high-speed video results showing a slight over-estimation in regards to the bubble size.
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Date Issued: 2011
Identifier: CFE0004006, ucf:49185
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004006

Title: INTERACTION BETWEEN SECONDARY FLOW AND FILM COOLING JETS OF A REALISTIC ANNULAR AIRFOIL CASCADE (HIGH MACH NUMBER).
Creator: Nguyen, Cuong, Kapat, Jayanta, University of Central Florida
Abstract / Description: Film cooling is investigated on a flat plate both numerically and experimentally. Conical shaped film hole are investigated extensively and contribute to the current literature data, which is extremely rare in the open public domain. Both configuration of the cylindrical film holes, with and without a trench, are investigated in detail. Design of experiment technique was performed to find an optimum combination of both geometrical and fluid parameters to achieve the best film cooling...
Show moreFilm cooling is investigated on a flat plate both numerically and experimentally. Conical shaped film hole are investigated extensively and contribute to the current literature data, which is extremely rare in the open public domain. Both configuration of the cylindrical film holes, with and without a trench, are investigated in detail. Design of experiment technique was performed to find an optimum combination of both geometrical and fluid parameters to achieve the best film cooling performance. From this part of the study, it shows that film cooling performance can be enhanced up to 250% with the trenched film cooling versus non-trenched case provided the same amount of coolant. Since most of the relevant open literature is about film cooling on flat plate endwall cascade with linear extrusion airfoil, the purpose of the second part of this study is to examine the interaction of the secondary flow inside a 3D cascade and the injected film cooling jets. This is employed on the first stage of the aircraft gas turbine engine to protect the curvilinear (annular) endwall platform. The current study investigates the interaction between injected film jets and the secondary flow both experimentally and numerically at high Mach number (M=0.7). Validation shows good agreement between obtained data with the open literature. In general, it can be concluded that with an appropriate film coolant to mainstream blowing ratio, one can not only achieve the best film cooling effectiveness (FCE or η) on the downstream endwall but also maintain almost the same aerodynamic loss as in the un-cooled baseline case. Film performance acts nonlinearly with respect to blowing ratios as with film cooling on flat plate, in the other hand, with a right blowing ratio, film cooling performance is not affect much by secondary flow. In turn, film cooling jets do not increase pressure loss at the downstream wake area of the blades.
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Date Issued: 2010
Identifier: CFE0003546, ucf:48944
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003546

Title: BEYOND POSTMODERN MARGINS: THEORIZING POSTFEMINIST CONSEQUENCES THROUGH POPULAR FEMALE REPRESENTATION.
Creator: Mosher, Victoria, Campbell, James, University of Central Florida
Abstract / Description: In 1988, Linda Nicholson and Nancy Fraser published an article entitled "Social Criticism Without Philosophy: An Encounter Between Feminism and Postmodernism," arguing that this essay would provide a jumping point for discussion between feminisms and postmodernisms within academia. Within this essay, Nicholson and Fraser largely disavow a number of second wave feminist theories due to their essentialist and foundationalist underpinnings in favor of a set of postmodernist frameworks that might...
Show moreIn 1988, Linda Nicholson and Nancy Fraser published an article entitled "Social Criticism Without Philosophy: An Encounter Between Feminism and Postmodernism," arguing that this essay would provide a jumping point for discussion between feminisms and postmodernisms within academia. Within this essay, Nicholson and Fraser largely disavow a number of second wave feminist theories due to their essentialist and foundationalist underpinnings in favor of a set of postmodernist frameworks that might help feminist theorists overcome these epistemological impediments. A "postmodern feminism," Nicholson and Fraser claim, would become "the theoretical counterpart of a broader, richer, more complex, and multilayered solidarity, the sort of solidarity which is essential for overcoming the oppression of women" (35). Interpreting "Social Criticism" through a feminist cultural studies model in which texts are understood to be simultaneously constituted by and reflective of their own sociopolitical spaces, I argue that the construction of Nicholson and Fraser's "postmodern feminism" is, first and foremost, neither a postmodernist critique nor a means of overcoming the pitfalls of essentialism and foundationalism. Instead, the construction of this theoretical paradigm can be shown to be complicit with postfeminist discourses, wherein an implicitly patriarchal discourse of postmodernism is called upon to repair the deficiencies of feminisms, deficiencies that postmodernisms, in some ways, helped to bring into view. To provide a conceptual backing for these claims, I move toward an examination of mass culture, surveying the similarities between "Social Criticism" and the film What Women Want. Such a comparison, I suggest, facilitates a better understanding of how "Social Criticism" can be shown to be imbedded in a postfeminist narrative structure in which feminisms are relegated to a discursively subordinate gendered position in relation to postmodernisms. Finally, in what I find to be the most important aspect of this thesis' inquiry, I ask what it means to build a "broader, richer, more complex, and multilayered solidarity" by disavowing second wave feminisms in favor of postmodernisms. I conclude that, in using postmodernisms as a panacea for feminist theories, Nicholson and Fraser curtail what might have been a rigorous interrogation of and direct engagement with second wave feminist theories that would also attend to the phallogocentric underpinnings of postmodern theories. To underline the potential consequences, I turn to a set of televisual and filmic texts including Sex and the City, Desperate Housewives, and The Devil Wears Prada to gauge what their "postmodern feminism" might represent in practice rather than what it entails as philosophy. This juxtaposition of these two differently defined and yet overwhelmingly similar postmodern feminisms, I propose, underscores the potential that Nicholson and Fraser may have instituted a postmodern feminist methodology in which it is possible that feminisms might emerge not as discourses essential for "overcoming the oppression of women" but rather as discourses that can be critiqued into oblivion.
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Date Issued: 2008
Identifier: CFE0002141, ucf:47518
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002141

Title: Physiological Reactions to Uncanny Stimuli: Substantiation of Self-Assessment and Individual Perception in User Enjoyment and Comfort.
Creator: Ballion, Tatiana, Sims, Valerie, Chin, Matthew, Jones, Donald, University of Central Florida
Abstract / Description: There is abundant anecdotal evidence substantiating Mori's initial observation of the "uncanny valley", a point at which human response to non-human entities drops sharply with respect to comfort (Mori, 1970), and the construct itself has a long-standing history in both Robotics and Psychology. Currently, many fields such as design, training, entertainment, and education make use of heuristic approaches to accommodate the anticipated needs of the user/consumer/audience in certain important...
Show moreThere is abundant anecdotal evidence substantiating Mori's initial observation of the "uncanny valley", a point at which human response to non-human entities drops sharply with respect to comfort (Mori, 1970), and the construct itself has a long-standing history in both Robotics and Psychology. Currently, many fields such as design, training, entertainment, and education make use of heuristic approaches to accommodate the anticipated needs of the user/consumer/audience in certain important aspects. This is due to the lack of empirical substantiation or, in some cases, the impossibility of rigorous quantification; one such area is with respect to the user's experience of uncanniness, a feeling of "eeriness" or "wrongness" when interacting with artefacts or environments. Uncanniness, however, continues to be defined and measured in a largely subjective way, and often after the fact; an experience or product's uncanny features are pointed out after the item has been markedly avoided or complained about by the general public. These studies are among the first seeking to determine a constellation of personality traits and physiological responses that incline the user to have a more frequent or profound (")uncanny" reaction when presented with stimuli meeting the criteria for a level of "eeriness". In study 1, 395 adults were asked to categorize 200 images as uncanny, neutral, pleasant, or other. In Study 2, physiological and eye-tracking data was collected from twenty two adults as they viewed uncanny, neutral and pleasant images culled from study 1. This research identifies components of the uncanny valley related to subjective assessment, personality factors (using the HEXACO and Anthropomorphic Tendencies Scale), and biophysical measures, and found that traits unique to Emotionality on the HEXACO inventory, compounded with a form of anthropomorphism demonstrates a level of relationship to the subjective experience of uncanny stimuli. There is evidence that HEXACO type and forms of anthropomorphic perception mediates the biophysical expression and the subjective perception of the stimuli. In keeping with psychological hypotheses, stimuli to which the participants had greatest response centered on death, the threat of death, or mismatched/absent facial features.
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Date Issued: 2012
Identifier: CFE0004354, ucf:49454
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004354

Title: Deposition and characterization studies of boron carbon nitride (BCN) thin films prepared by dual target sputtering.
Creator: Prakash, Adithya, Sundaram, Kalpathy, Kapoor, Vikram, Yuan, Jiann-Shiun, Jin, Yier, Chow, Louis, University of Central Florida
Abstract / Description: As complementary metal-oxide semiconductor (CMOS) devices shrink to smaller size, the problems related to circuit performance such as critical path signal delay are becoming a pressing issue. These delays are a result of resistance and capacitance product (RC time constant) of the interconnect circuit. A novel material with reduced dielectric constants may compromise both the thermal and mechanical properties that can lead to die cracking during package and other reliability issues. Boron...
Show moreAs complementary metal-oxide semiconductor (CMOS) devices shrink to smaller size, the problems related to circuit performance such as critical path signal delay are becoming a pressing issue. These delays are a result of resistance and capacitance product (RC time constant) of the interconnect circuit. A novel material with reduced dielectric constants may compromise both the thermal and mechanical properties that can lead to die cracking during package and other reliability issues. Boron carbon nitride (BCN) compounds have been expected to combine the excellent properties of boron carbide (B4C), boron nitride (BN) and carbon nitride (C3N4), with their properties adjustable, depending on composition and structure. BCN thin film is a good candidate for being hard, dense, pore-free, low-k dielectric with values in the range of 1.9 to 2.1. Excellent mechanical properties such as adhesion, high hardness and good wear resistance have been reported in the case of sputtered BCN thin films. Problems posed by high hardness materials such as diamonds in high cutting applications and the comparatively lower hardness of c-BN gave rise to the idea of a mixed phase that can overcome these problems with a minimum compromise in its properties. A hybrid between semi-metallic graphite and insulating h-BN may show adjusted semiconductor properties. BCN exhibits the potential to control optical bandgap (band gap engineering) by atomic composition, hence making it a good candidate for electronic and photonic devices. Due to tremendous bandgap engineering capability and refractive index variability in BCN thin film, it is feasible to develop filters and mirrors for use in ultra violet (UV) wavelength region. It is of prime importance to understand process integration challenges like deposition rates, curing, and etching, cleaning and polishing during characterization of low-k films. The sputtering technique provides unique advantages over other techniques such as freedom to choose the substrate material and a uniform deposition over relatively large area. BCN films are prepared by dual target reactive magnetron sputtering from a B4C and BN targets using DC and RF powers respectively. In this work, an investigation of mechanical, optical, chemical, surface and device characterizations is undertaken. These holistic and thorough studies, will provide the insight into the capability of BCN being a hard, chemically inert, low-k, wideband gap material, as a potential leader in semiconductor and optics industry.
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Date Issued: 2016
Identifier: CFE0006378, ucf:51496
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006378

Title: INVESTIGATION OF PS-PVD AND EB-PVD THERMAL BARRIER COATINGS OVER LIFETIME USING SYNCHROTRON X-RAY DIFFRACTION.
Creator: Northam, Matthew, Raghavan, Seetha, Ghosh, Ranajay, Vaidyanathan, Raj, University of Central Florida
Abstract / Description: Extreme operating temperatures within the turbine section of jet engines require sophisticated methods of cooling and material protection. Thermal barrier coatings (TBCs) achieve this through a ceramic coating applied to a substrate material (nickel-based superalloy). Electron-beam physical vapor deposition (EB-PVD) is the industry standard coating used on jet engines. By tailoring the microstructure of an emerging deposition method, Plasma-spray physical vapor deposition (PS-PVD), similar...
Show moreExtreme operating temperatures within the turbine section of jet engines require sophisticated methods of cooling and material protection. Thermal barrier coatings (TBCs) achieve this through a ceramic coating applied to a substrate material (nickel-based superalloy). Electron-beam physical vapor deposition (EB-PVD) is the industry standard coating used on jet engines. By tailoring the microstructure of an emerging deposition method, Plasma-spray physical vapor deposition (PS-PVD), similar microstructures to that of EB-PVD coatings can be fabricated, allowing the benefits of strain tolerance to be obtained while improving coating deposition times. This work investigates the strain through depth of uncycled and cycled samples using these coating techniques with synchrotron X-ray diffraction (XRD). In the TGO, room temperature XRD measurements indicated samples of both deposition methods showed similar in-plane compressive stresses after 300 and 600 thermal cycles. In-situ XRD measurements indicated similar high-temperature in-plane and out-of-plane stress in the TGO and no spallation after 600 thermal cycles for both coatings. Tensile in-plane residual stresses were found in the YSZ uncycled PS-PVD samples, similar to APS coatings. PS-PVD samples showed in most cases, higher compressive residual in-plane stress at the YSZ/TGO interface. These results provide valuable insight for optimizing the PS-PVD processing parameters to obtain strain compliance similar to that of EB-PVD. Additionally, external cooling methods used for thermal management in jet engine turbines were investigated. In this work, an additively manufactured lattice structure providing transpiration cooling holes is designed and residual strains are measured within an AM transpiration cooling sample using XRD. Strains within the lattice structure were found to have greater variation than that of the AM solid wall. These results provide valuable insight into the viability of implementing an AM lattice structure in turbine blades for the use of transpiration cooling.
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Date Issued: 2019
Identifier: CFE0007844, ucf:52830
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007844

Title: SPRAY COOLING FOR LAND, SEA, AIR AND SPACE BASED APPLICATIONS,A FLUID MANAGEMENT SYSTEM FOR MULTIPLE NOZZLE SPRAY COOLING AND A GUIDE TO HIGH HEAT FLUX HEATER DESIGN.
Creator: Glassman, Brian, Chow, Louis, University of Central Florida
Abstract / Description: This thesis is divided into four distinct chapters all linked by the topic of spray cooling. Chapter one gives a detailed categorization of future and current spray cooling applications, and reviews the major advantages and disadvantages that spray cooling has over other high heat flux cooling techniques. Chapter two outlines the developmental goals of spray cooling, which are to increase the output of a current system and to enable new technologies to be technically feasible. Furthermore,...
Show moreThis thesis is divided into four distinct chapters all linked by the topic of spray cooling. Chapter one gives a detailed categorization of future and current spray cooling applications, and reviews the major advantages and disadvantages that spray cooling has over other high heat flux cooling techniques. Chapter two outlines the developmental goals of spray cooling, which are to increase the output of a current system and to enable new technologies to be technically feasible. Furthermore, this chapter outlines in detail the impact that land, air, sea, and space environments have on the cooling system and what technologies could be enabled in each environment with the aid of spray cooling. In particular, the heat exchanger, condenser and radiator are analyzed in their corresponding environments. Chapter three presents an experimental investigation of a fluid management system for a large area multiple nozzle spray cooler. A fluid management or suction system was used to control the liquid film layer thickness needed for effective heat transfer. An array of sixteen pressure atomized spray nozzles along with an imbedded fluid suction system was constructed. Two surfaces were spray tested one being a clear grooved Plexiglas plate used for visualization and the other being a bottom heated grooved 4.5 x 4.5 cm2 copper plate used to determine the heat flux. The suction system utilized an array of thin copper tubes to extract excess liquid from the cooled surface. Pure water was ejected from two spray nozzle configurations at flow rates of 0.7 L/min to 1 L/min per nozzle. It was found that the fluid management system provided fluid removal efficiencies of 98% with a 4-nozzle array, and 90% with the full 16-nozzle array for the downward spraying orientation. The corresponding heat fluxes for the 16 nozzle configuration were found with and without the aid of the fluid management system. It was found that the fluid management system increased heat fluxes on the average of 30 W/cm2 at similar values of superheat. Unfortunately, the effectiveness of this array at removing heat at full levels of suction is approximately 50% & 40% of a single nozzle at respective 10„aC & 15„aC values of superheat. The heat transfer data more closely resembled convective pooling boiling. Thus, it was concluded that the poor heat transfer was due to flooding occurring which made the heat transfer mechanism mainly forced convective boiling and not spray cooling. Finally, Chapter four gives a detailed guide for the design and construction of a high heat flux heater for experimental uses where accurate measurements of surface temperatures and heat fluxes are extremely important. The heater designs presented allow for different testing applications; however, an emphasis is placed on heaters designed for use with spray cooling.
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Date Issued: 2005
Identifier: CFE0000473, ucf:46351
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000473

Title: Secondary World: The Limits of Ludonarrative.
Creator: Dannelly, David, Adams, JoAnne, Price, Mark, Poindexter, Carla, Kovach, Keith, University of Central Florida
Abstract / Description: Secondary World: The Limits of Ludonarrative is a series of short narrative animations that are a theoretical treatise on the limitations of western storytelling in video games. The series covers specific topics relating to film theory, game design and art theory: specifically those associated with Gilles Deleuze, Jean Baudrillard, Jay Bolter, Richard Grusin and Andy Clark. The use of imagery, editing and presentation is intended to physically represent an extension of myself and my thinking...
Show moreSecondary World: The Limits of Ludonarrative is a series of short narrative animations that are a theoretical treatise on the limitations of western storytelling in video games. The series covers specific topics relating to film theory, game design and art theory: specifically those associated with Gilles Deleuze, Jean Baudrillard, Jay Bolter, Richard Grusin and Andy Clark. The use of imagery, editing and presentation is intended to physically represent an extension of myself and my thinking process and which are united through the common thread of my personal feelings, thoughts and experiences in the digital age.
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Date Issued: 2014
Identifier: CFE0005155, ucf:50704
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005155

film (20)	+ -
Film (16)	+ -
film cooling (11)	+ -
microbudget (8)	+ -
thin film (8)	+ -

digital (7)	+ -
Film Cooling (6)	+ -
Thin Films (6)	+ -
cinema (6)	+ -
Cinema (5)	+ -
Experimental (4)	+ -
documentary (4)	+ -
film studies (4)	+ -
horror (4)	+ -
CIGS (3)	+ -
CIGSeS (3)	+ -
Cu (3)	+ -
Digital Cinema (3)	+ -
Documentary (3)	+ -
Filmmaking (3)	+ -
Gas Turbine (3)	+ -
MFA (3)	+ -
Narrative (3)	+ -
Sputtering (3)	+ -
Thin Film (3)	+ -
art (3)	+ -
filmmaking (3)	+ -
heat transfer (3)	+ -
Adiabatic Film Cooling Effectiveness (2)	+ -
Agglomeration (2)	+ -

ETD Collection (120)	+ -
Honors Collection (15)	+ -

University of Central Florida (135)	+ -
Kapat, Jayanta (20)	+ -
Stoeckl, Ula (12)	+ -
Mills, Lisa (11)	+ -
Sandler, Barry (10)	+ -

Sundaram, Kalpathy (9)	+ -
Danker, Elizabeth (8)	+ -
Harris, Christopher (8)	+ -
Peterson, Lisa (8)	+ -
Vasu Sumathi, Subith (8)	+ -
Shults, Katherine (7)	+ -
Chow, Louis (6)	+ -
Coffey, Kevin (6)	+ -
Dhere, Neelkanth (6)	+ -
Deng, Weiwei (5)	+ -
Gay, Andrew (5)	+ -
Peters, Philip (5)	+ -
Schlow, Stephen (5)	+ -
Finch, Randy (4)	+ -
Kumar, Ranganathan (4)	+ -
Raghavan, Seetha (4)	+ -
Adams, JoAnne (3)	+ -
Ahmed, Kareem (3)	+ -
Heinrich, Helge (3)	+ -
Jones, Robert (3)	+ -
Kassab, Alain (3)	+ -
Malocha, Donald (3)	+ -
Peale, Robert (3)	+ -
Perez, Jonathan (3)	+ -
Poindexter, Carla (3)	+ -

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