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Title: SAVAGE IN LIMBO: A STUDY IN LIGHTING DESIGN.
Creator: Haines, Kenneth, Perry, Charles, University of Central Florida
Abstract / Description: Designing the elements of a theatrical production is a unique and often experimental process. This process changes from show to show, and it can be difficult for a viewer to differentiate mistakes from design choices without a background in lighting. That is why it is important to take a look at the design process step by step. Two goals I strove for when designing Savage In Limbo were, how the director's concept blended with a design and if the integrity of the designer's vision was evident...
Show moreDesigning the elements of a theatrical production is a unique and often experimental process. This process changes from show to show, and it can be difficult for a viewer to differentiate mistakes from design choices without a background in lighting. That is why it is important to take a look at the design process step by step. Two goals I strove for when designing Savage In Limbo were, how the director's concept blended with a design and if the integrity of the designer's vision was evident on stage. To explore these goals, script analysis and consideration of the director's vision are two very important processes. Additionally, an exploration of the design process will better describe the growth and personal achievements of the design. This thesis will show the process of the lighting design for The University of Central Florida's 2011 production of John Patrick Shanley's Savage In Limbo. The project will highlight the design achievements and the goals explained previously, and create a formal dialogue on this specific design in order to provide insight into the process. When analyzing the design it was important that I assessed the process as well as the product by looking at whether the design met the expectations of the script and audience. This thesis will also explore how my past experiences, education and current skill level have prepared me for this design process in order to create a guideline for others interested in the development of knowledge needed for design.
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Date Issued: 2012
Identifier: CFH0004206, ucf:44969
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004206

Title: DIGITAL SIGNAL PROCESSING TECHNIQUES FOR COHERENT OPTICAL COMMUNICATION.
Creator: Goldfarb, Gilad, Li, Guifang, University of Central Florida
Abstract / Description: Coherent detection with subsequent digital signal processing (DSP) is developed, analyzed theoretically and numerically and experimentally demonstrated in various fiber‐optic transmission scenarios. The use of DSP in conjunction with coherent detection unleashes the benefits of coherent detection which rely on the preservation of full information of the incoming field. These benefits include high receiver sensitivity, the ability to achieve high spectral‐efficiency and the use of...
Show moreCoherent detection with subsequent digital signal processing (DSP) is developed, analyzed theoretically and numerically and experimentally demonstrated in various fiber‐optic transmission scenarios. The use of DSP in conjunction with coherent detection unleashes the benefits of coherent detection which rely on the preservation of full information of the incoming field. These benefits include high receiver sensitivity, the ability to achieve high spectral‐efficiency and the use of advanced modulation formats. With the immense advancements in DSP speeds, many of the problems hindering the use of coherent detection in optical transmission systems have been eliminated. Most notably, DSP alleviates the need for hardware phase‐locking and polarization tracking, which can now be achieved in the digital domain. The complexity previously associated with coherent detection is hence significantly diminished and coherent detection is once again considered a feasible detection alternative. In this thesis, several aspects of coherent detection (with or without subsequent DSP) are addressed. Coherent detection is presented as a means to extend the dispersion limit of a duobinary signal using an analog decision‐directed phase‐lock loop. Analytical bit‐error ratio estimation for quadrature phase‐shift keying signals is derived. To validate the promise for high spectral efficiency, the orthogonal‐wavelength‐division multiplexing scheme is suggested. In this scheme the WDM channels are spaced at the symbol rate, thus achieving the spectral efficiency limit. Theory, simulation and experimental results demonstrate the feasibility of this approach. Infinite impulse response filtering is shown to be an efficient alternative to finite impulse response filtering for chromatic dispersion compensation. Theory, design considerations, simulation and experimental results relating to this topic are presented. Interaction between fiber dispersion and nonlinearity remains the last major challenge deterministic effects pose for long‐haul optical data transmission. Experimental results which demonstrate the possibility to digitally mitigate both dispersion and nonlinearity are presented. Impairment compensation is achieved using backward propagation by implementing the split‐step method. Efficient realizations of the dispersion compensation operator used in this implementation are considered. Infinite‐impulse response and wavelet‐based filtering are both investigated as a means to reduce the required computational load associated with signal backward‐propagation. Possible future research directions conclude this dissertation.
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Date Issued: 2008
Identifier: CFE0002384, ucf:47763
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002384

Title: Method for Real-Time Signal Selection for Passive Coherent Location Systems.
Creator: Johnson, Nicholas, Jones, W Linwood, Gong, Xun, Mikhael, Wasfy, Rockway, John, Lichtenberg, Christopher, University of Central Florida
Abstract / Description: Passive coherent location (PCL) systems use signals of opportunity to perform traditional radar detection, targeting, and tracking functions. Traditionally these signals include FM radio, digital TV, GSM, and GPS because of their availability in most urban environments. A benefit of having an abundance of signals is the ability to choose which of those best meet the desired system intentions. For example, one may want to choose a digital TV signal over an FM radio signal due to its range...
Show morePassive coherent location (PCL) systems use signals of opportunity to perform traditional radar detection, targeting, and tracking functions. Traditionally these signals include FM radio, digital TV, GSM, and GPS because of their availability in most urban environments. A benefit of having an abundance of signals is the ability to choose which of those best meet the desired system intentions. For example, one may want to choose a digital TV signal over an FM radio signal due to its range resolution characteristics. This work presents a novel algorithm for characterizing commercial signals for use in a PCL system. By analyzing each signal's ambiguity function in terms of amplitude, transmitter geometry, range and Doppler resolution, and sidelobe levels, a comparative evaluation can be made to decide which signals are best suited for an intended radar function. In addition, this research shows that multiple signals can be combined in the detection process to increase the probability of detection over that of a single signal. Finally, this research investigates the geometric considerations for PCL systems in terms of bistatic radar geometry. The results show zones of linear and non-linear relationships between time delay, range, and Doppler frequency.
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Date Issued: 2017
Identifier: CFE0007123, ucf:51964
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007123

Title: Sleep Disturbances Among Firefighters: The Impact Of Shift Work On Sleep And Cognition.
Creator: Stout, Jeremy, Beidel, Deborah, Bowers, Clint, Paulson, Daniel, Dziegielewski, Sophia, University of Central Florida
Abstract / Description: A comprehensive sleep assessment of 45 firefighters was conducted over 9- days in an effort to determine the impact of their 24 hour work and 48 hour off work schedule on their sleep duration, sleep quality, processing speed, sustained attention, vigilance, and mental health. Chronic patterns of poor sleep are associated with an increased likelihood of performing poorly on tasks that require processing speed and sustained attention/vigilance which could lead to firefighters' suboptimal work...
Show moreA comprehensive sleep assessment of 45 firefighters was conducted over 9- days in an effort to determine the impact of their 24 hour work and 48 hour off work schedule on their sleep duration, sleep quality, processing speed, sustained attention, vigilance, and mental health. Chronic patterns of poor sleep are associated with an increased likelihood of performing poorly on tasks that require processing speed and sustained attention/vigilance which could lead to firefighters' suboptimal work performance or an increased risk of injury. Firefighters completed sleep actigraphy, self- report measures, as well as neuropsychological sub-tests at their beginning of their shift and immediately at the end of their work shift. As measured by actigraphy, firefighters in this sample slept an average of 5 hours and 20.99 minutes at work, which was significantly less than was found in a large sample of U.S. working adults. Firefighters endorsed poor sleep efficiency and poor sleep quality as assessed by self-report and objective actigraphy. One limitation is that only 12 of the 45 firefighters endorsed responding to a nighttime call during the work night that occurred between the two neuropsychological assessments. Comparing changes in neuropsychological performance between firefighters who had disrupted sleep compared to firefighters who did not, significant performances decrements were evident only for the psychomotor vigilance test (PVT) reaction time. If confirmed with a larger sample, the results suggest that reaction time may be a sensitive indicator of decreasing cognitive performance because of sleep loss. Limitations, future study directions, and recommendations are discussed.
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Date Issued: 2018
Identifier: CFE0007251, ucf:52190
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007251

Title: Spatial Models with Specific Error Structures.
Creator: Adu, Nathaniel, Richardson, Gary, Mohapatra, Ram, Song, Zixia, Lang, Sheau-Dong, University of Central Florida
Abstract / Description: The purpose of this dissertation is to study the first order autoregressive model in the spatial context with specific error structures. We begin by supposing that the error structure has a long memory in both the i and the j components. Whenever the model parameters alpha and beta equal one, the limiting distribution of the sequence of normalized Fourier coefficients of the spatial process is shown to be a function of a two parameter fractional Brownian sheet. This result is used to find the...
Show moreThe purpose of this dissertation is to study the first order autoregressive model in the spatial context with specific error structures. We begin by supposing that the error structure has a long memory in both the i and the j components. Whenever the model parameters alpha and beta equal one, the limiting distribution of the sequence of normalized Fourier coefficients of the spatial process is shown to be a function of a two parameter fractional Brownian sheet. This result is used to find the limiting distribution of the periodogram ordinate of the spatial process under the null hypothesis that alpha equals one and beta equals one. We then give the limiting distribution of the normalized Fourier coefficients of the spatial process for both a moving average and autoregressive error structure. Two cases of autoregressive errors are considered. The first error model is autoregressive in one component and the second is autoregressive in both components. We show that the normalizing factor needed to ensure convergence in distribution of the sequence of Fourier coefficients is different in the moving average case, and the two autoregressive cases. In other words, the normalizing factor differs in each of these three cases.Finally, a specific case of the functional central limit theorem in the spatial setting is stated and proved. The assumptions made here are placed on the autocovariance functions. We then discuss some specific examples and provide a test statistics based on the periodogram ordinate.
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Date Issued: 2019
Identifier: CFE0007772, ucf:52385
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007772

Title: MEASURING MULTILEVEL CONSTRUCTS: THEORETICAL AND METHODOLOGICAL FEATURES OF TEAM BEHAVIORAL PROCESS UNDER COMPILATIONAL MODELS.
Creator: Murase, Toshio, Dechurch, Leslie, Salas, Eduardo, Bowers, Clint, Kapucu, Naim, University of Central Florida
Abstract / Description: Since at least the 1950s, researchers interested in studying the dynamics of small groups have struggled with how best to measure interaction processes. Although team process measurement issues are not particularly unique in terms of content, measuring multilevel phenomena presents an interesting problem because structural aspects are integral components of emergence. The elemental content of multilevel phenomena is wholly unique and distinguishable from the elemental content of composite...
Show moreSince at least the 1950s, researchers interested in studying the dynamics of small groups have struggled with how best to measure interaction processes. Although team process measurement issues are not particularly unique in terms of content, measuring multilevel phenomena presents an interesting problem because structural aspects are integral components of emergence. The elemental content of multilevel phenomena is wholly unique and distinguishable from the elemental content of composite units, and emerges as individual behaviors compile to higher levels of analyses. Analogous to chemical structures, behavioral phenomena manifest at higher levels in different structural patterns as members connect to one another through dynamic interactions. Subsequently, multilevel phenomena are more appropriately characterized in terms of pattern in addition to the traditionally measured intensity. The vast majority of teams research conceptualizes and operationalizes multilevel phenomena based on compositional (i.e., additive) models. This approach impedes the further advancement of the science of team effectiveness by capturing content and intensity, but not structure. This dissertation argues that compilational models better capture content, intensity, and structure, and therefore represent a preferred alternative for conceptualizing and operationalizing team processes. This dissertation details measurement issues associated with compositional models in teams research, and provides concepts helpful for reconceptualizing team processes as compilational forms.
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Date Issued: 2011
Identifier: CFE0004145, ucf:49048
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004145

Title: Who do I Play: Appraising the Impact of Teacher-in-Role with Kindergartners in an ESOL Classroom.
Creator: Brantley, Kathryn, Wood, Mary, Thaxton, Terry, Niess, Christopher, University of Central Florida
Abstract / Description: Educators employing process drama, a non-presentational dramatic form, establish memorable classroom environments where students co-author their learning with teachers. Process drama facilitators often use the dramatic structure of teacher-in-role to guide and support the students. An instructor heightens tension, introduces new ideas, and encourages participation by engaging alongside students as a character. An educator employing process drama needs to determine the appropriate type of role...
Show moreEducators employing process drama, a non-presentational dramatic form, establish memorable classroom environments where students co-author their learning with teachers. Process drama facilitators often use the dramatic structure of teacher-in-role to guide and support the students. An instructor heightens tension, introduces new ideas, and encourages participation by engaging alongside students as a character. An educator employing process drama needs to determine the appropriate type of role to impact the development of a classroom drama; while negotiating tension felt between desires for student-led discovery and the necessity of meeting curriculum benchmarks.Academic studies establish process drama as a tool to aid English Students of Other Languages or ESOL classrooms. Process drama heightens comprehension, whole language usage and ownership of learning. Using the methodology of reflective practice I analyzed my teaching in role to determine how I negotiate diverse and conflicting objectives. I facilitated a six week process drama with four to six-year-old ESOL students at a learning centre in Hong Kong. This study improved this teacher's understanding and usage of teacher-in-role. The ideals of a process centered classroom were not always realized, but the needs of the population necessitated adaption from expectations. The experiences of the researcher indicate ambiguous character may not be the best way to motivate dialogue among this population of ESOL students. Students' age and English experience suggests using co-participant characters whose motivations are clearly defined. This study contributes to the discussion on what differing (")role types(") offer facilitators of process drama and how it may be used to meet demands of curriculum including development of performances. Process drama with very young students presents a field for further research investigating methods and practices to effectively structure process dramas that address their learning.
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Date Issued: 2012
Identifier: CFE0004227, ucf:48989
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004227

Title: INVESTIGATING THE OPTIMAL PRESENTATION OF FEEDBACK IN SIMULATION-BASED TRAINING: AN APPLICATION OF THE COGNITIVE THEORY OF MULTIMEDIA LEARNING.
Creator: Van Buskirk, Wendi, Bowers, Clint, University of Central Florida
Abstract / Description: There are many different training interventions that can be used in simulation based training systems (e.g., cueing, hinting, highlighting, deliberate practice, etc.). However, the most widely used training intervention in the military is feedback, most often presented in the form of a debrief. With advances in technology, it is possible to measure and diagnose performance in real-time. Thus it is possible to provide immediate feedback during scenarios. However, training systems designers...
Show moreThere are many different training interventions that can be used in simulation based training systems (e.g., cueing, hinting, highlighting, deliberate practice, etc.). However, the most widely used training intervention in the military is feedback, most often presented in the form of a debrief. With advances in technology, it is possible to measure and diagnose performance in real-time. Thus it is possible to provide immediate feedback during scenarios. However, training systems designers should not consider the timing of feedback in isolation. There are other parameters of feedback that must also be considered which may have an impact on performance. Specifically, feedback content and modality may also have an impact on the appropriate timing of feedback and its' effectiveness in simulation training environments. Moreno and Mayer (2000) propose a cognitive theory of multimedia learning which describes how instruction is perceived and processed by a trainee. Using this theoretical framework, I investigate the optimal use of feedback while considering the interaction of feedback timing, content, and modality in scenario-based training environments. In order to investigate the relationship between the timing, modality, and content of feedback, a 2 (immediate, delayed) X 2 (visual, auditory) X 2 (process, outcome) between-subjects design was used (a no feedback control condition was also included). Ninety participants were randomly assigned to the nine experimental groups. These participants performed a visual-spatial military task called the Forward Observer PC-based Simulation. Results indicated that receiving feedback was beneficial to improve performance as compared to receiving no feedback. As hypothesized, during a visual-spatial task, auditory feedback presented during a scenario led to higher performance than visual feedback. Finally, while I did not support my hypothesis that an interaction between all three components of feedback would affect performance, it is promising that the pattern of results mirrored the hypothesized pattern. Theoretical and practical implications, as well as limitations of the current study and directions for future research are discussed.
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Date Issued: 2011
Identifier: CFE0003604, ucf:48875
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003604

Title: QUERY PROCESSING IN LOCATION-BASED SERVICES.
Creator: Liu, Fuyu, Hua, Kien, University of Central Florida
Abstract / Description: With the advances in wireless communication technology and advanced positioning systems, a variety of Location-Based Services (LBS) become available to the public. Mobile users can issue location-based queries to probe their surrounding environments. One important type of query in LBS is moving monitoring queries over mobile objects. Due to the high frequency in location updates and the expensive cost of continuous query processing, server computation capacity and wireless communication...
Show moreWith the advances in wireless communication technology and advanced positioning systems, a variety of Location-Based Services (LBS) become available to the public. Mobile users can issue location-based queries to probe their surrounding environments. One important type of query in LBS is moving monitoring queries over mobile objects. Due to the high frequency in location updates and the expensive cost of continuous query processing, server computation capacity and wireless communication bandwidth are the two limiting factors for large-scale deployment of moving object database systems. To address both of the scalability factors, distributed computing has been considered. These schemes enable moving objects to participate as a peer in query processing to substantially reduce the demand on server computation, and wireless communications associated with location updates. In the first part of this dissertation, we propose a distributed framework to process moving monitoring queries over moving objects in a spatial network environment. In the second part of this dissertation, in order to reduce the communication cost, we leverage both on-demand data access and periodic broadcast to design a new hybrid distributed solution for moving monitoring queries in an open space environment. Location-based services make our daily life more convenient. However, to receive the services, one has to reveal his/her location and query information when issuing location-based queries. This could lead to privacy breach if these personal information are possessed by some untrusted parties. In the third part of this dissertation, we introduce a new privacy protection measure called query l-diversity, and provide two cloaking algorithms to achieve both location k-anonymity and query l-diversity to better protect user privacy. In the fourth part of this dissertation, we design a hybrid three-tier architecture to help reduce privacy exposure. In the fifth part of this dissertation, we propose to use Road Network Embedding technique to process privacy protected queries.
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Date Issued: 2010
Identifier: CFE0003487, ucf:48949
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003487

Title: THE MEMORY OF FORGOTTEN THINGS.
Creator: Metz, Brittany, Poindexter, Carla, University of Central Florida
Abstract / Description: This thesis investigates my lack of childhood memories and documents how my artwork stands in as a substitute for that lost memory. The first part of the thesis analyzes my early life and influences; the second part analyzes my art making and process. The narrative style of writing is intentionally autobiographical to mimic the narrative style and structure of the thesis installation. My upbringing, interests, creative process, access to materials, and inspiration are fully explored. The...
Show moreThis thesis investigates my lack of childhood memories and documents how my artwork stands in as a substitute for that lost memory. The first part of the thesis analyzes my early life and influences; the second part analyzes my art making and process. The narrative style of writing is intentionally autobiographical to mimic the narrative style and structure of the thesis installation. My upbringing, interests, creative process, access to materials, and inspiration are fully explored. The impact my early life has on my current work is evident. Real memory is combined with created memory in the thesis multi-media installation. I wish to transport the viewer into the dreamlike space I have constructed with found objects and multi-media materials by offering an immersive experience into my world.
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Date Issued: 2011
Identifier: CFE0003649, ucf:48814
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003649

Title: Application of Modeling and Simulation to Reduce Costs of Acquisition within Triple Constraints.
Creator: Mohammad, Syed, Kincaid, John, Shumaker, Randall, Wiegand, Rudolf, Richardson, Paul, University of Central Florida
Abstract / Description: A key component of defense acquisition programs operating using the Integrated Defense Acquisition, Technology, and Logistics Life Cycle Management System is the reliance on the triple constraints of cost, schedule, and performance. While the use of Modeling and Simulation tools and capabilities is prevalent and well established in the Research and Development, Analysis, and Training domains, acquisition programs have been reluctant to use Modeling and Simulation in any great depth due to...
Show moreA key component of defense acquisition programs operating using the Integrated Defense Acquisition, Technology, and Logistics Life Cycle Management System is the reliance on the triple constraints of cost, schedule, and performance. While the use of Modeling and Simulation tools and capabilities is prevalent and well established in the Research and Development, Analysis, and Training domains, acquisition programs have been reluctant to use Modeling and Simulation in any great depth due to inaccessibility of tools, Subject Matter Experts, and implications to cost and schedule. This presents a unique Simulation Management challenge which requires an in-depth understanding of the technical capabilities available within an organization, their applicability to support immediate needs, and the flexibility to utilize these capabilities within the programmatic environment to provide a value added service. The focus of this dissertation is to study the use of Modeling and Simulation in the Defense arena, and to review the applicability of Modeling and Simulation within programmatic acquisition environments which are constrained by cost, schedule, and performance. This research draws comparisons between Modeling and Simulation to other Process Improvement initiatives, such as Lean and Six Sigma, and reviews case studies involving the application of Modeling and Simulation within triple constrained environments. The development of alternate scenarios allows cost benefit analysis to be conducted for each scenario and alternate scenario, developing a case for whether or not the application of Modeling and Simulation within the triple constrained environment delivered any consequential benefit to the acquisition process. Observations are made regarding the level of Modeling and Simulation as applied within each case study, and generalized recommendations are made for the inclusion of cost benefit analysis methodologies for analyzing proposed Modeling and Simulation activities within acquisition programs. Limitations and shortcomings of the research activity are discussed, along with recommendations for potential future work in the Simulation Management field, both with respect to the specific case studies reviewed in this study and the general field.
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Date Issued: 2012
Identifier: CFE0004415, ucf:49396
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004415

Title: CHARACTERIZATION AND AQUEOUS COLLOIDAL PROCESSING OF TUNGSTEN NANO-POWDERS.
Creator: Yang, Zhengtao, Sohn, Yongho, University of Central Florida
Abstract / Description: Extensive attention has been paid to consolidate nanoparticles into nanocrystalline components that possess better properties than their coarse-grained counterparts. Nanocrystalline monolithic tungsten (W) has been envisaged to possess better properties than coarse-grained tungsten and to improve the performance of many military components. Commercially available nano-W powders were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy...
Show moreExtensive attention has been paid to consolidate nanoparticles into nanocrystalline components that possess better properties than their coarse-grained counterparts. Nanocrystalline monolithic tungsten (W) has been envisaged to possess better properties than coarse-grained tungsten and to improve the performance of many military components. Commercially available nano-W powders were characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES) and Brunauer, Emmett, and Teller (BET) measurement. While the bulk of nano-W powders consisted of bcc-W as confirmed by XRD and TEM, much of their surface consisted of WO3 with traces of WO2 and WC. Despite the irregular morphology and agglomerates greater than 1 m in size, the diameter of individual nano-W powders ranged from 30 to 100 nm with a surface area of 10.4 m2/g. To obtain green bodies of higher densities and more homogeneous microstructures after consolidation, W nanopowders were de-agglomerated in water and slip cast in plaster molds. De-agglomeration in water was conducted by repeated ultrasonication, washing, centrifuge and pH adjustment. The change in particle size and morphology was examined via SEM. After the initial surface oxide was removed by repeated washing, the reactivity of W nanoparticles to water was somewhat inhibited. Increasing the number of cycles for ultrasonication and washing increased the pH, the degree of de-agglomeration and the stability of W suspension. The zeta potential was more negative with increasing pH and most negative at pH values close to 5. Viscosity also decreased with increasing pH and reached a minimum at a pH 5. To obtain the highest solid loading with the lowest viscosity, the pH value of W suspension was adjusted to 5 using aqueous tetramethylammonium hydroxide solutions. The relative density of the slip cast increased with longer ultrasonic time, increasing slurry pH up to 5, and consequent increase in solids loading. Smaller particles were separated from larger ones by ultrasonication, washing with water and centrifugation. At a 27.8 vol.% solids loading, the size-separated fine W slurry was slip cast into pellets with relative green densities up to 41.3 % and approximate particle sizes of 100 nm. W powders were also ultrasonicated in aqueous poly (ethyleneimine) (PEI) solutions with various concentrations. SEM examinations of particle sizes showed that 1 wt.% PEI led to the optimum dispersion and ultrasonication for longer time with a low power resulted in better dispersion. 0.5 g of W powders were ultrasonicated in 10 ml aqueous poly (allylamine hydrochloride) (PAH) solutions with molar concentrations ranging from 0.01 to 0.05 M. W suspensions with 0.03 M and 0.04 M PAH after two washing cycles showed improved dispersion. Cold isostatic pressing can further increase the green density following slip casting. Sintered slip casts made from de-agglomerated nanoparticle W showed a lower density, more uniform microstructure, smaller grains and smaller pores than the sintered dry pressed pellets.
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Date Issued: 2009
Identifier: CFE0002706, ucf:48144
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002706

Title: A QUALITATIVE CASE STUDY OF NOVICE KENYAN PRIMARY SCHOOL TEACHERS: WHAT MESSAGES TRANSMITTED BY THE TEACHER TRAINING COLLEGES ARE INTERNALIZED AND APPLIED?.
Creator: Kranz, Carol, Biraimah, Karen, University of Central Florida
Abstract / Description: The method of instruction and the formal curriculum within two Kenyan teacher training colleges were studied in order to discover which messages regarding pedagogical practice are internalized within novice Kenyan primary school teachers and then actualized within their classrooms. An educational connoisseurship approach was utilized to give descriptive, interpretive, evaluative, and thematic insight. Three data streams were collected through interview, observation, and design evaluation in...
Show moreThe method of instruction and the formal curriculum within two Kenyan teacher training colleges were studied in order to discover which messages regarding pedagogical practice are internalized within novice Kenyan primary school teachers and then actualized within their classrooms. An educational connoisseurship approach was utilized to give descriptive, interpretive, evaluative, and thematic insight. Three data streams were collected through interview, observation, and design evaluation in order to establish structural corroboration and internal validity. The study found that the method of instruction by the teacher training college faculty was teacher-centered and utilized lower order cognitive methodology. Though the formal curriculum design was strong, it too promoted lower cognitive processes. These two messages, teacher-centered pedagogies and lower cognitive processes, are being internalized and applied by the novice teachers and maybe affecting the quality of education in Kenyan schools. The results of this study suggest that pedagogical skills promoting higher cognitive levels should be developed through in-service training in Kenyan training colleges and primary schools as a way to improve the quality of education in this country.
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Date Issued: 2011
Identifier: CFE0003883, ucf:48729
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003883

Title: RESEARCH IN HIGH PERFORMANCE AND LOW POWER COMPUTER SYSTEMS FOR DATA-INTENSIVE ENVIRONMENT.
Creator: Shang, pengju, Wang, Jun, University of Central Florida
Abstract / Description: The evolution of computer science and engineering is always motivated by the requirements for better performance, power efficiency, security, user interface (UI), etc. The first two factors are potential tradeoffs: better performance usually requires better hardware, e.g., the CPUs with larger number of transistors, the disks with higher rotation speed; however, the increasing number of transistors on the single die or chip reveals super-linear growth in CPU power consumption, and the change...
Show moreThe evolution of computer science and engineering is always motivated by the requirements for better performance, power efficiency, security, user interface (UI), etc. The first two factors are potential tradeoffs: better performance usually requires better hardware, e.g., the CPUs with larger number of transistors, the disks with higher rotation speed; however, the increasing number of transistors on the single die or chip reveals super-linear growth in CPU power consumption, and the change in disk rotation speed has a quadratic effect on disk power consumption. We propose three new systematic approaches, Transactional RAID, data-affinity-aware data placement DAFA and Modeless power management, to tackle the performance problem in Database systems, large scale clusters or cloud platforms, and the power management problem in Chip Multi Processors, respectively. The first design, Transactional RAID (TRAID), is motivated by the fact that in recent years, more storage system applications have employed transaction processing techniques to ensure data integrity and consistency. In transaction processing systems(TPS), log is a kind of redundancy to ensure transaction ACID (atomicity, consistency, isolation, durability) properties and data recoverability. Furthermore, high reliable storage systems, such as redundant array of inexpensive disks (RAID), are widely used as the underlying storage system for Databases to guarantee system reliability and availability with high I/O performance. However, the Databases and storage systems tend to implement their independent fault tolerant mechanisms from their own perspectives and thereby leading to potential high overhead. We observe the overlapped redundancies between the TPS and RAID systems, and propose a novel reliable storage architecture called Transactional RAID (TRAID). TRAID deduplicates this overlap by only logging one compact version (XOR results) of recovery references for the updating data. It minimizes the amount of log content as well as the log flushing overhead, thereby boosts the overall transaction processing performance. At the same time, TRAID guarantees comparable RAID reliability, the same recovery correctness and ACID semantics of traditional transactional processing systems. On the other hand, the emerging myriad data intensive applications place a demand for high-performance computing resources with massive storage. Academia and industry pioneers have been developing big data parallel computing frameworks and large-scale distributed file systems (DFS) widely used to facilitate the high-performance runs of data-intensive applications, such as bio-informatics, astronomy, and high-energy physics. Our recent work reported that data distribution in DFS can significantly affect the efficiency of data processing and hence the overall application performance. This is especially true for those with sophisticated access patterns. For example, Yahoo's Hadoop clusters employs a random data placement strategy for load balance and simplicity. This allows the MapReduce programs to access all the data (without or not distinguishing interest locality) at full parallelism. Our work focuses on Hadoop systems. We observed that the data distribution is one of the most important factors that affect the parallel programming performance. However, the default Hadoop adopts random data distribution strategy, which does not consider the data semantics, specifically, data affinity. We propose a Data-Affinity-Aware (DAFA) data placement scheme to address the above problem. DAFA builds a history data access graph to exploit the data affinity. According to the data affinity, DAFA re-organizes data to maximize the parallelism of the affinitive data, and also subjective to the overall load balance. This enables DAFA to realize the maximum number of map tasks with data-locality. Besides the system performance, power consumption is another important concern of current computer systems. In the U.S. alone, the energy used by servers which could be saved comes to 3.17 million tons of carbon dioxide, or 580,678 cars. However, the goals of high performance and low energy consumption are at odds with each other. An ideal power management strategy should be able to dynamically respond to the change (either linear or nonlinear, or non-model) of workloads and system configuration without violating the performance requirement. We propose a novel power management scheme called MAR (modeless, adaptive, rule-based) in multiprocessor systems to minimize the CPU power consumption under performance constraints. By using richer feedback factors, e.g. the I/O wait, MAR is able to accurately describe the relationships among core frequencies, performance and power consumption. We adopt a modeless control model to reduce the complexity of system modeling. MAR is designed for CMP (Chip Multi Processor) systems by employing multi-input/multi-output (MIMO) theory and per-core level DVFS (Dynamic Voltage and Frequency Scaling).
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Date Issued: 2011
Identifier: CFE0003910, ucf:48749
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003910

Title: IPCL1- An Interactive Process Control Language.
Creator: Erlandson, Richard A., Bauer, Christian S., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; This report documents a Process Control Language. It was written to provide an easy-to-use, user-friendly language to control a manufacturing-type process. It is not assumed the user is proficient or even familiar with any computer languages. The user should be able to grasp the simple set of commands available and begin writing user programs in a short period of time. Emphasis has been placed on error messages to inform the user of...
Show moreUniversity of Central Florida College of Engineering Thesis; This report documents a Process Control Language. It was written to provide an easy-to-use, user-friendly language to control a manufacturing-type process. It is not assumed the user is proficient or even familiar with any computer languages. The user should be able to grasp the simple set of commands available and begin writing user programs in a short period of time. Emphasis has been placed on error messages to inform the user of the type of error and enough information to correct it. The language was written in PDP-11 assembly language and run on a 11/34 computer in the Microcomputer Laboratory at the University of Central Florida.
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Date Issued: 1985
Identifier: CFR0004771, ucf:52983
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0004771

Title: Application of system dynamics techniques to war game modeling.
Creator: Amico, G. Vincent, null, null, Engineering
Abstract / Description: Florida Technological University College of Engineering Thesis; Military War Gaming has developed from- the chess-like games to the elaborate computer simulations of today, using high-speed, general-purpose, digital computers. This Research Report will briefly review modern war-game developments with emphasis on real-t h e training systems. The application of system dynamics techniques developed by Jay W. Forrester to war-game modeling is explored. A simple destroyer versus submarine model is...
Show moreFlorida Technological University College of Engineering Thesis; Military War Gaming has developed from- the chess-like games to the elaborate computer simulations of today, using high-speed, general-purpose, digital computers. This Research Report will briefly review modern war-game developments with emphasis on real-t h e training systems. The application of system dynamics techniques developed by Jay W. Forrester to war-game modeling is explored. A simple destroyer versus submarine model is developed. Results indicate that the system dynamics modeling technique is a powerful and effective tool. However, the Dynamo language could be substantially improved by a more powerful logical statement capability.
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Date Issued: 1973
Identifier: CFR0003482, ucf:53032
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0003482

Title: Application of Computer War Gaming in the Evaluation of Missile Performance Requirements for Air to Air Engagements.
Creator: Berman, Joy F., Clapp, Donald E., Engineering
Abstract / Description: Florida Technological University College of Engineering Thesis
Date Issued: 1974
Identifier: CFR0011983, ucf:53097
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0011983

Title: Machine Learning from Casual Conversation.
Creator: Mohammed Ali, Awrad, Sukthankar, Gita, Wu, Annie, Boloni, Ladislau, University of Central Florida
Abstract / Description: Human social learning is an effective process that has inspired many existing machine learning techniques, such as learning from observation and learning by demonstration. In this dissertation, we introduce another form of social learning, Learning from a Casual Conversation (LCC). LCC is an open-ended machine learning system in which an artificially intelligent agent learns from an extended dialog with a human. Our system enables the agent to incorporate changes into its knowledge base,...
Show moreHuman social learning is an effective process that has inspired many existing machine learning techniques, such as learning from observation and learning by demonstration. In this dissertation, we introduce another form of social learning, Learning from a Casual Conversation (LCC). LCC is an open-ended machine learning system in which an artificially intelligent agent learns from an extended dialog with a human. Our system enables the agent to incorporate changes into its knowledge base, based on the human's conversational text input. This system emulates how humans learn from each other through a dialog. LCC closes the gap in the current research that is focused on teaching specific tasks to computer agents. Furthermore, LCC aims to provide an easy way to enhance the knowledge of the system without requiring the involvement of a programmer. This system does not require the user to enter specific information; instead, the user can chat naturally with the agent. LCC identifies the inputs that contain information relevant to its knowledge base in the learning process. LCC's architecture consists of multiple sub-systems combined to perform the task. Its learning component can add new knowledge to existing information in the knowledge base, confirm existing information, and/or update existing information found to be related to the user input. %The test results indicate that the prototype was successful in learning from a conversation. The LCC system functionality was assessed using different evaluation methods. This includes tests performed by the developer, as well as by 130 human test subjects. Thirty of those test subjects interacted directly with the system and completed a survey of 13 questions/statements that asked the user about his/her experience using LCC. A second group of 100 human test subjects evaluated the dialogue logs of a subset of the first group of human testers. The collected results were all found to be acceptable and within the range of our expectations.
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Date Issued: 2019
Identifier: CFE0007503, ucf:52634
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007503

Title: Deposition Thickness Modeling and Parameter Identification for Spray Assisted Vacuum Filtration Process in Additive Manufacturing.
Creator: Mark, August, Xu, Yunjun, Gou, Jihua, Lin, Kuo-Chi, University of Central Florida
Abstract / Description: To enhance mechanical and/or electrical properties of composite materials used in additive manufacturing, nanoparticles are often time deposited to form nanocomposite layers. To customize the mechanical and/or electrical properties, the thickness of such nanocomposite layers must be precisely controlled. A thickness model of filter cakes created through a spray assisted vacuum filtration is presented in this paper, to enable the development of advanced thickness controllers. The mass transfer...
Show moreTo enhance mechanical and/or electrical properties of composite materials used in additive manufacturing, nanoparticles are often time deposited to form nanocomposite layers. To customize the mechanical and/or electrical properties, the thickness of such nanocomposite layers must be precisely controlled. A thickness model of filter cakes created through a spray assisted vacuum filtration is presented in this paper, to enable the development of advanced thickness controllers. The mass transfer dynamics in the spray atomization and vacuum filtration are studied for the mass of solid particles and mass of water in differential areas, and then the thickness of a filter cake is derived. A two-loop nonlinear constrained optimization approach is used to identify the unknown parameters in the model. Experiments involving depositing carbon nanofibers in a sheet of paper are used to measure the ability of the model to mimic the filtration process.
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Date Issued: 2015
Identifier: CFE0005974, ucf:50788
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005974

Title: Entanglement and Coherence in Classical and Quantum Optics.
Creator: Kagalwala, Kumel, Saleh, Bahaa, Abouraddy, Ayman, Christodoulides, Demetrios, Leuenberger, Michael, University of Central Florida
Abstract / Description: We explore the concepts of coherence and entanglement as they apply to both the classical and quantum natures of light. In the classical domain, we take inspiration from the tools and concepts developed in foundational quantum mechanics and quantum information science to gain a better understanding of classical coherence theory of light with multiple degrees of freedom (DoFs). First, we use polarization and spatial parity DoFs to demonstrate the notion of classical entanglement, and show that...
Show moreWe explore the concepts of coherence and entanglement as they apply to both the classical and quantum natures of light. In the classical domain, we take inspiration from the tools and concepts developed in foundational quantum mechanics and quantum information science to gain a better understanding of classical coherence theory of light with multiple degrees of freedom (DoFs). First, we use polarization and spatial parity DoFs to demonstrate the notion of classical entanglement, and show that Bell's measure can serve as a useful tool in distinguishing between classical optical coherence theory. Second, we establish a methodical yet versatile approach called 'optical coherency matrix tomography' for reconstructing the coherency matrix of an electromagnetic beam with multiple DoFs. This technique exploits the analogy between this problem in classical optics and that of tomographically reconstructing the density matrix associated with multipartite quantum states in quantum information science. Third, we report the first experimental measurements of the 4 x 4 coherency matrix associated with an electromagnetic beam in which polarization and a spatial DoF are relevant, ranging from the traditional two-point Young's double slit to spatial parity and orbital angular momentum modes. In the quantum domain, we use the modal structure of classical fields to develop qubits and structure Hilbert spaces for use in quantum information processing. Advancing to three-qubit logic gates is an important step towards the success of optical schemes for quantum computing. We experimentally implement a variety of two- and three- qubit, linear and deterministic, single-photon, controlled, quantum logic gates using polarization and spatial parity qubits. Lastly, we demonstrate the implementation of two-qubit single-photon logic using polarization and orbital angular momentum qubits.
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Date Issued: 2015
Identifier: CFE0006334, ucf:51546
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006334

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