Current Search: physicalism (x)
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- Title
- Security of Autonomous Systems under Physical Attacks: With application to Self-Driving Cars.
- Creator
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Dutta, Raj, Jin, Yier, Sundaram, Kalpathy, DeMara, Ronald, Zhang, Shaojie, Zhang, Teng, University of Central Florida
- Abstract / Description
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The drive to achieve trustworthy autonomous cyber-physical systems (CPS), which can attain goals independently in the presence of significant uncertainties and for long periods of time without any human intervention, has always been enticing. Significant progress has been made in the avenues of both software and hardware for fulfilling these objectives. However, technological challenges still exist and particularly in terms of decision making under uncertainty. In an autonomous system,...
Show moreThe drive to achieve trustworthy autonomous cyber-physical systems (CPS), which can attain goals independently in the presence of significant uncertainties and for long periods of time without any human intervention, has always been enticing. Significant progress has been made in the avenues of both software and hardware for fulfilling these objectives. However, technological challenges still exist and particularly in terms of decision making under uncertainty. In an autonomous system, uncertainties can arise from the operating environment, adversarial attacks, and from within the system. As a result of these concerns, human-beings lack trust in these systems and hesitate to use them for day-to-day use.In this dissertation, we develop algorithms to enhance trust by mitigating physical attacks targeting the integrity and security of sensing units of autonomous CPS. The sensors of these systems are responsible for gathering data of the physical processes. Lack of measures for securing their information can enable malicious attackers to cause life-threatening situations. This serves as a motivation for developing attack resilient solutions.Among various security solutions, attention has been recently paid toward developing system-level countermeasures for CPS whose sensor measurements are corrupted by an attacker. Our methods are along this direction as we develop an active and multiple passive algorithm to detect the attack and minimize its effect on the internal state estimates of the system. In the active approach, we leverage a challenge authentication technique for detection of two types of attacks: The Denial of Service (DoS) and the delay injection on active sensors of the systems. Furthermore, we develop a recursive least square estimator for recovery of system from attacks. The majority of the dissertation focuses on designing passive approaches for sensor attacks. In the first method, we focus on a linear stochastic system with multiple sensors, where measurements are fused in a central unit to estimate the state of the CPS. By leveraging Bayesian interpretation of the Kalman filter and combining it with the Chi-Squared detector, we recursively estimate states within an error bound and detect the DoS and False Data Injection attacks. We also analyze the asymptotic performance of the estimator and provide conditions for resilience of the state estimate.Next, we propose a novel distributed estimator based on l1 norm optimization, which could recursively estimate states within an error bound without restricting the number of agents of the distributed system that can be compromised. We also extend this estimator to a vehicle platoon scenario which is subjected to sparse attacks. Furthermore, we analyze the resiliency and asymptotic properties of both the estimators. Finally, at the end of the dissertation, we make an initial effort to formally verify the control system of the autonomous CPS using the statistical model checking method. It is done to ensure that a real-time and resource constrained system such as a self-driving car, with controllers and security solutions, adheres to strict timing constrains.
Show less - Date Issued
- 2018
- Identifier
- CFE0007174, ucf:52253
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007174
- Title
- EVALUATING AN ONLINE PERSONALIZED FAMILY-BASED INTERVENTION TO PROMOTE HEALTHY LIFESTYLE CHANGES.
- Creator
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Hayes, Sharon, Tantleff-Dunn, Stacey, University of Central Florida
- Abstract / Description
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The current study evaluated the initial feasibility, efficacy, and acceptability of a motivationally-tailored family-based intervention designed to promote the adoption of healthy lifestyle behaviors associated with physical activity and nutrition. Parents (N=132) of children 6 to 11 years old were randomly assigned to the intervention or control condition, and they completed a series of online questionnaires. Intervention participants (n=61) received a single motivationally-tailored feedback...
Show moreThe current study evaluated the initial feasibility, efficacy, and acceptability of a motivationally-tailored family-based intervention designed to promote the adoption of healthy lifestyle behaviors associated with physical activity and nutrition. Parents (N=132) of children 6 to 11 years old were randomly assigned to the intervention or control condition, and they completed a series of online questionnaires. Intervention participants (n=61) received a single motivationally-tailored feedback report via e-mail. Control participants (n=71) completed measures and immediately received information about a free online resource that provides information about healthy lifestyle behaviors (www.mypyramid.gov). Feasibility data indicate that an online feedback program has high dissemination potential (parents from 31 states participated). However, the current methodology is not sufficient in reaching families who are at greatest risk for developing chronic health conditions associated with obesity or low activity level. In general, the intervention was acceptable to parents. Outcome data revealed that the intervention and control groups did not differ significantly on most variables at one month follow-up. Exploratory analyses provided additional evidence for the importance of including parents and targeting parent-child interactions in the context of pediatric nutrition and physical activity interventions. Limitations and future directions are discussed.
Show less - Date Issued
- 2010
- Identifier
- CFE0003359, ucf:48438
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003359
- Title
- Translocation of a semiflexible polymer through a nanopore.
- Creator
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Adhikari, Ramesh, Bhattacharya, Aniket, Chen, Bo, Kokoouline, Viatcheslav, Hernandez, Florencio, University of Central Florida
- Abstract / Description
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The transport of a biomolecule through a nanopore occurs in many biological functions such as, DNA or RNA transport across nuclear pores and the translocation of proteins across the eukaryotic endoplasmic reticulum. In addition to the biological processes, it has potential applications in technology such as, drug delivery, gene therapy, and single molecule sensing. The DNA translocation through a synthetic nanopore device is considered as the basis for cheap and fast sequencing technology....
Show moreThe transport of a biomolecule through a nanopore occurs in many biological functions such as, DNA or RNA transport across nuclear pores and the translocation of proteins across the eukaryotic endoplasmic reticulum. In addition to the biological processes, it has potential applications in technology such as, drug delivery, gene therapy, and single molecule sensing. The DNA translocation through a synthetic nanopore device is considered as the basis for cheap and fast sequencing technology. Motivated by the experimental advances, many theoretical models have been developed. In this thesis, we explore the dynamics of driven translocation of a semiflexible polymer through a nanopore in two dimensions (2D) using Langevin dynamics (LD) simulation. By carrying out extensive simulation as a function of different parameters such as, driving force, length and rigidity of the chain, viscosity of the solvent, and diameter of the nanopore, we provide a detailed description of the translocation process. Our studies are relevant for fundamental understanding of the translocation process which is essential for making accurate nano-pore based devices.
Show less - Date Issued
- 2015
- Identifier
- CFE0005915, ucf:50830
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005915
- Title
- Solving Constraint Satisfaction Problems with Matrix Product States.
- Creator
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Pelton, Sabine, Mucciolo, Eduardo, Ishigami, Masa, Leuenberger, Michael, University of Central Florida
- Abstract / Description
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In the past decade, Matrix Product State (MPS) algorithms have emerged as an efficient method of modeling some many-body quantum spin systems. Since spin system Hamiltonians can be considered constraint satisfaction problems (CSPs), it follows that MPS should provide a versatile framework for studying a variety of general CSPs. In this thesis, we apply MPS to two types of CSP. First, use MPS to simulate adiabatic quantum computation (AQC), where the target Hamiltonians are instances of a...
Show moreIn the past decade, Matrix Product State (MPS) algorithms have emerged as an efficient method of modeling some many-body quantum spin systems. Since spin system Hamiltonians can be considered constraint satisfaction problems (CSPs), it follows that MPS should provide a versatile framework for studying a variety of general CSPs. In this thesis, we apply MPS to two types of CSP. First, use MPS to simulate adiabatic quantum computation (AQC), where the target Hamiltonians are instances of a fully connected, random Ising spin glass. Results of the simulations help shed light on why AQC fails for some optimization problems. We then present the novel application of a modified MPS algorithm to classical Boolean satisfiability problems, specifically k-SAT and max k-SAT. By construction, the algorithm also counts solutions to a given Boolean formula (\#-SAT). For easy satisfiable instances, the method is more expensive than other existing algorithms; however, for hard and unsatisfiable instances, the method succeeds in finding satisfying assignments where other algorithms fail to converge.
Show less - Date Issued
- 2017
- Identifier
- CFE0006902, ucf:51713
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006902
- Title
- Experimental Study of Sinkhole Failure Related to Groundwater Level Drops.
- Creator
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Alrowaimi, Mohamed, Chopra, Manoj, Nam, Boo Hyun, Yun, Hae-Bum, Sallam, Amr, University of Central Florida
- Abstract / Description
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Sinkholes are natural geohazard phenomena that cause damage to property and may lead to loss of life. They can also cause added pollution to the aquifer by draining unfiltered water from streams, wetland, and lakes into the aquifer. Sinkholes occur in a very distinctive karst geology where carbonate, limestone, dolomite, or gypsum, are encountered as the bedrock that can naturally be dissolved by groundwater circulating through them. Sinkholes can occur gradually or suddenly with catastrophic...
Show moreSinkholes are natural geohazard phenomena that cause damage to property and may lead to loss of life. They can also cause added pollution to the aquifer by draining unfiltered water from streams, wetland, and lakes into the aquifer. Sinkholes occur in a very distinctive karst geology where carbonate, limestone, dolomite, or gypsum, are encountered as the bedrock that can naturally be dissolved by groundwater circulating through them. Sinkholes can occur gradually or suddenly with catastrophic impact depending on the geology and hydrology of the area. Predicting the formation and the collapse of a sinkhole based on the current ground investigation technologies is limited by the high levels of uncertainties in the soil properties and behavior. It is possible that progressing sinkholes can be missed by geotechnical site investigations especially during the development of a very wide area. In this study, a laboratory-scale sinkhole model was constructed to physically simulate the sinkhole phenomenon. The physical model was designed to monitor a network of groundwater table over time around a predetermined sinkhole location. This model was designed to establish a correlation between the groundwater table drops and the sinkhole development. The experimental small-scale model showed that there is a groundwater cone of depression that forms prior the surface collapse of the sinkhole. The cone of water depression can be used to identify the potential location of the sinkhole at early stage of the overburden underground cavities formation in a reverse manner. In addition, monitoring of single groundwater well showed that groundwater level signal has some sudden water drops (progressive drops) which occur at different times (time lags) during the sinkhole development. A time frequency analysis was also used in this study to detect the pattern of these progressive drops of the groundwater table readings. It is observed, based on the model, that the development and growth of sinkhole can be correlated to progressive drops of the groundwater table since the drops start at the monitoring wells that are closer radially to the center of the sinkhole. Subsequently, with time, these drops get transferred to more distant monitoring wells. The time frequency analysis is used to decompose and detect the progressive drops by using a Pattern Detection Algorithm called Auto Modulating Detection Pattern Algorithm (AMD), which was developed by Yun (2013). The results of this analysis showed that the peaks of these progressive drops in the raw groundwater readings are a good indicator of the potential location of sinkholes at early stage when there are no any visible depression of the ground surface. Finally, the effect of several soil parameters on the cone of the water depression during the sinkhole formation is studied. The parametric study showed that both of overburden soil thickness and the initial (encountered) groundwater table level have a clear impact on the time of the sinkhole collapse. While this model used a predetermined crack location to study the groundwater level response around it, the concept of groundwater drops as an indicator of sinkhole progression and collapse may be used to determine the ultimate location of the sinkhole. By monitoring the changes in natural groundwater levels in the field from either an existing network of groundwater monitoring wells or additional installation, the methodology discussed in this dissertation may be used for possible foreseeing of the surface collapse of sinkholes.
Show less - Date Issued
- 2016
- Identifier
- CFE0006249, ucf:51060
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006249
- Title
- Dangerous Instincts: A Collection of Poetry.
- Creator
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Holt, Kirsten, Nwakanma, Obi, Bartkevicius, Jocelyn, Riegel, Katherine, University of Central Florida
- Abstract / Description
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Dangerous Instincts is a collection of poems unified thematically by recurring and interstitial questions of the wilderness, the natural sciences - particularly astrophysics - the occult, and the mythic universe. These poems explore the mystical implications of the natural world and its meaning in the aesthetic consciousness, particularly in a highly secular century. Implied is the poet's self-discovery and search for the divine. The collection emerges, not simply as interpretation, but a...
Show moreDangerous Instincts is a collection of poems unified thematically by recurring and interstitial questions of the wilderness, the natural sciences - particularly astrophysics - the occult, and the mythic universe. These poems explore the mystical implications of the natural world and its meaning in the aesthetic consciousness, particularly in a highly secular century. Implied is the poet's self-discovery and search for the divine. The collection emerges, not simply as interpretation, but a means of coming to terms with the fear of and compulsion to question the universe, and through those questions find illumination in the ordinariness of lived life and in the mystery and magic of complex phenomena. As a whole, the work is largely lyrical; occasionally it calls upon forms such as the villanelle and ekphrasis as deliberate formal poetic experiments. Sometimes the images are familiar recreations of creation myths and forest fires, and sometimes they range into as private and esoteric a realm as occult rituals, Scottish fairytale, and quantum entanglement.Dangerous Instincts is divided into five sections that explore the physical realm in terms of distances: from outward to inward, from heights to depths, and from beyond the speaker's understanding to intrinsically self-reflexive poems written to amplify my notion that at the heart of poetry is myth.
Show less - Date Issued
- 2013
- Identifier
- CFE0004691, ucf:49869
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004691
- Title
- DESIGN AND ASSESSMENT OF COMPACT OPTICAL SYSTEMS TOWARDS SPECIAL EFFECTS IMAGING.
- Creator
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Chaoulov, Vesselin, Rolland, Jannick, University of Central Florida
- Abstract / Description
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A main challenge in the field of special effects is to create special effects in real time in a way that the user can preview the effect before taking the actual picture or movie sequence. There are many techniques currently used to create computer-simulated special effects, however current techniques in computer graphics do not provide the option for the creation of real-time texture synthesis. Thus, while computer graphics is a powerful tool in the field of special effects, it is neither...
Show moreA main challenge in the field of special effects is to create special effects in real time in a way that the user can preview the effect before taking the actual picture or movie sequence. There are many techniques currently used to create computer-simulated special effects, however current techniques in computer graphics do not provide the option for the creation of real-time texture synthesis. Thus, while computer graphics is a powerful tool in the field of special effects, it is neither portable nor does it provide work in real-time capabilities. Real-time special effects may, however, be created optically. Such approach will provide not only real-time image processing at the speed of light but also a preview option allowing the user or the artist to preview the effect on various parts of the object in order to optimize the outcome. The work presented in this dissertation was inspired by the idea of optically created special effects, such as painterly effects, encoded in images captured by photographic or motion picture cameras. As part of the presented work, compact relay optics was assessed, developed, and a working prototype was built. It was concluded that even though compact relay optics can be achieved, further push for compactness and cost-effectiveness was impossible in the paradigm of bulk macro-optics systems. Thus, a paradigm for imaging with multi-aperture micro-optics was proposed and demonstrated for the first time, which constitutes one of the key contributions of this work. This new paradigm was further extended to the most general case of magnifying multi-aperture micro-optical systems. Such paradigm allows an extreme reduction in size of the imaging optics by a factor of about 10 and a reduction in weight by a factor of about 500. Furthermore, an experimental quantification of the feasibility of optically created special effects was completed, and consequently raytracing software was developed, which was later commercialized by SmARTLens(TM). While the art forms created via raytracing were powerful, they did not predict all effects acquired experimentally. Thus, finally, as key contribution of this work, the principles of scalar diffraction theory were applied to optical imaging of extended objects under quasi-monochromatic incoherent illumination in order to provide a path to more accurately model the proposed optical imaging process for special effects obtained in the hardware. The existing theoretical framework was generalized to non-paraxial in- and out-of-focus imaging and results were obtained to verify the generalized framework. In the generalized non-paraxial framework, even the most complex linear systems, without any assumptions for shift invariance, can be modeled and analyzed.
Show less - Date Issued
- 2005
- Identifier
- CFE0000513, ucf:46447
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000513
- Title
- THE ASSOCIATION BETWEEN MATERNAL RESILIENCY, PERCEPTIONS OF TOUCH, AND REPORTS OF INFANT TOUCH.
- Creator
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D'Agostino, Lisa, Waldrop, Julee, University of Central Florida
- Abstract / Description
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The purpose of this research study is to measure how mothers perceive and use touch with their infants, and its association with maternal resiliency, a measure of coping ability. This is important because the inability to cope causes increased stress, which increases negative perceptions of life events, making it even more difficult to cope. In addition, research has yet to uncover whether or not resiliency is increased in mothers by the same touch and interactions that has been proven to...
Show moreThe purpose of this research study is to measure how mothers perceive and use touch with their infants, and its association with maternal resiliency, a measure of coping ability. This is important because the inability to cope causes increased stress, which increases negative perceptions of life events, making it even more difficult to cope. In addition, research has yet to uncover whether or not resiliency is increased in mothers by the same touch and interactions that has been proven to enhance development, attachment, and resiliency in infants. This study involved asking participants (mothers of infants <1 year of age) to complete demographic information and a survey composed of three questionnaires: the Mother-Infant Touch Survey, the Physical Contact Assessment, and the Resilience Scale. Although there were no statistically significant correlations between reported perceptions of touch, mother-infant touch and maternal resiliency, there were a couple of other findings that warrant further investigation. Hispanic mothers scored higher on the Resiliency Scale (RS-14) than Non-Hispanic mothers, and a linear trend was detected between mothers in the < 25 years of age group and higher scores on the RS-14. These findings may influence future research on the correlations between mother-infant touch and maternal coping ability.
Show less - Date Issued
- 2013
- Identifier
- CFH0004329, ucf:45032
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004329
- Title
- INTERVENTIONS FOR CHILDHOOD OBESITY: EVALUATING TECHNOLOGICAL APPLICATIONS TARGETING PHYSICAL ACTIVITY LEVEL AND DIET.
- Creator
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DiPietro, Jessica, Norris, Anne, University of Central Florida
- Abstract / Description
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Overweight and obese children have increased risks for multiple preventable diseases and conditions which can impair their physiological health and significantly increases the overall cost of their healthcare. Free mobile applications and technology for weight loss, dietary tracking, and physical activity may be quite useful for monitoring nutritional intake and exercise to facilitate weight loss. If so, nurses are well positioned to recommend such tools as part of their efforts to prevent...
Show moreOverweight and obese children have increased risks for multiple preventable diseases and conditions which can impair their physiological health and significantly increases the overall cost of their healthcare. Free mobile applications and technology for weight loss, dietary tracking, and physical activity may be quite useful for monitoring nutritional intake and exercise to facilitate weight loss. If so, nurses are well positioned to recommend such tools as part of their efforts to prevent childhood obesity and help children and parents better manage childhood obesity when it is present. However, there are no guidelines that nurses can use to determine what applications or technologies are most beneficial to children and their parents. The purpose of this project is to develop such guidelines based on a review of the scientific literature published in the last 5 years. Articles regarding healthy-lifestyle promoting mobile applications and technological approaches to health and fitness interventions were identified by searching articles indexed by CINAHL, Psychinfo, Medline, ERIC, IEEE Xplore, and Academic Search Premier. Identified articles were assessed using Melnyk's hierarchy of evidence and organized into tables so that implications for research and suggestions for practice could be made.
Show less - Date Issued
- 2014
- Identifier
- CFH0004616, ucf:45255
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004616
- Title
- Exploring the Self-Reported Dietary Habits and Physical Activity Between Athletes and Non-Athletes in Four Central Florida Public High Schools.
- Creator
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Redd, Alison, Valdes, Anna, Stout, Jeffrey, Fisher, Thomas, Garcia, Jeanette, Fukuda, David, University of Central Florida
- Abstract / Description
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The federal reimbursable meals offered in American school cafeterias have recently been revised with improved nutrition standards yet may not meet the needs of student athletes who require additional energy intake. While many epidemiological studies report high numbers of adolescents who are overweight or obese, there are close to eight million high school students involved in interscholastic sports(-)more now than ever before. Therefore, the purpose of this research is to establish...
Show moreThe federal reimbursable meals offered in American school cafeterias have recently been revised with improved nutrition standards yet may not meet the needs of student athletes who require additional energy intake. While many epidemiological studies report high numbers of adolescents who are overweight or obese, there are close to eight million high school students involved in interscholastic sports(-)more now than ever before. Therefore, the purpose of this research is to establish participation rates in the federal school meals programs in a local Central Florida school district between athlete and non-athlete high school populations. Additionally, the study aimed to establish athlete and non-athlete participation rates in the federal free/reduced lunch program and determine the average number of hours spent in physical activity between athlete and non-athletes in one week. An online questionnaire was developed to assess students' self-reported energy intake and energy expenditure through sport participation and physical activity acquired during leisure time. Results of the study revealed no significance difference in federal school breakfast or lunch consumption rates between athletes and non-athletes. The study also revealed similar participation rates in the free and reduced lunch program between athlete and non-athletes when purchasing school lunches. Additionally, while non-athletes reported more average hours acquiring physical activity in their leisure time than athletes did, athletes accrued more average hours of overall physical activity due to time spent in interscholastic sport practice. Lastly, results determined significant differences in Body Mass Index (BMI) with athletes having lower BMIs than non-athletes. If meals policies evolve to be more accurately reflective of energy intake needs of athletes and non-athletes, school meals could appropriately fuel student performance in the classroom, the athletic field, and beyond.
Show less - Date Issued
- 2018
- Identifier
- CFE0007239, ucf:52230
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007239
- Title
- Kindergarten is Not Child's Play: An Exploration of Pedagogical Approaches Related to Learning in a Play-Based and a Contemporary Classroom at a Title I Elementary School.
- Creator
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Allee-Herndon, Karyn, Roberts, Sherron, Lue, Martha, Clark, M. H., Garcia, Jeanette, Hu, Bi Ying, University of Central Florida
- Abstract / Description
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This dissertation is divided into three separate, related, naturalistic, quasi-experimental research studies, all using data from two kindergarten classes at Gator Elementary, a public Title I elementary school in Sunshine District in Central Florida. Each of these studies tested hypotheses that kindergarten children, especially those from low socioeconomic backgrounds, will show greater gains in receptive vocabulary, executive function, and academic achievement when purposeful play is used...
Show moreThis dissertation is divided into three separate, related, naturalistic, quasi-experimental research studies, all using data from two kindergarten classes at Gator Elementary, a public Title I elementary school in Sunshine District in Central Florida. Each of these studies tested hypotheses that kindergarten children, especially those from low socioeconomic backgrounds, will show greater gains in receptive vocabulary, executive function, and academic achievement when purposeful play is used as a pedagogical approach than similar children in typical, contemporary kindergarten classrooms. The first study explored the effects of play-based and contemporary pedagogical approaches on students' receptive vocabulary using the PPVT-4, the second explored students' executive functions using the BRIEF2, and the third explored students' movements using Actigraph GT9X Link accelerometers. All three studies analyzed these data in relation to students' academic achievement as measured by i-Ready Diagnostic assessments. Statistically significant differences were detected in students' receptive vocabulary and reading growth as well as statistically significant differences in students' executive function health as reported by teachers and reading and math academic growth by classroom conditions. A strong association between receptive vocabulary and reading performances was revealed alongside strong negative correlations between levels of executive function concern and reading performance. No statistical differences in math growth between classrooms were found, although there was a moderate effect size, and less of an association between math performance and executive function presented. While strong correlations between academic achievement and total movement by day or movement types were revealed, these associations were inconsistent. Nor were there significant differences in movement by classroom conditions, although there was a moderate effect size suggesting some differences in movement by condition. The findings from this dissertation, while limited, point to a bourgeoning area of research connecting neuroscientific findings with developmentally appropriate practices to explore effective interventions to increase educational equity for vulnerable students.
Show less - Date Issued
- 2019
- Identifier
- CFE0007596, ucf:52556
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007596
- Title
- The Performance and Power Impact of Using Multiple DRAM Address Mapping Schemes in Multicore Processors.
- Creator
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Jadaa, Rami, Heinrich, Mark, DeMara, Ronald, Yuan, Jiann-Shiun, University of Central Florida
- Abstract / Description
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Lowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic...
Show moreLowest-level cache misses are satisfied by the main memory through a specific address mapping scheme that is hard-coded in the memory controller. A dynamic address mapping scheme technique is investigated to provide higher performance and lower power consumption, and a method to throttle memory to meet a specific power budget. Several experiments are conducted on single and multithreaded synthetic memory traces -to study extreme cases- and validate the usability of the proposed dynamic mapping scheme over the fixed one. Results show that applications' performance varies according to the mapping scheme used, and a dynamic mapping scheme achieves up to 2x increase in peak bandwidth utilization and around 30% higher energy efficiency than a system using only a single fixed scheme Moreover, the technique can be used to limit memory accesses into a subset of the memory devices by controlling data allocation at a finer granularity, providing a method to throttle main memory by allowing un-accessed devices to be put into power-down mode, hence saving power to meet a certain power budget.
Show less - Date Issued
- 2011
- Identifier
- CFE0004121, ucf:49118
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004121
- Title
- LASER INDUCED BREAKDOWN SPECTROSCOPY FOR DETECTION OF ORGANIC RESIDUES: IMPACT OF AMBIENT ATMOSPHERE AND LASER PARAMETERS.
- Creator
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Brown, Christopher, Richardson, Martin, University of Central Florida
- Abstract / Description
-
Laser Induced Breakdown Spectroscopy (LIBS) is showing great potential as an atomic analytical technique. With its ability to rapidly analyze all forms of matter, with little-to-no sample preparation, LIBS has many advantages over conventional atomic emission spectroscopy techniques. With the maturation of the technologies that make LIBS possible, there has been a growing movement to implement LIBS in portable analyzers for field applications. In particular, LIBS has long been considered the...
Show moreLaser Induced Breakdown Spectroscopy (LIBS) is showing great potential as an atomic analytical technique. With its ability to rapidly analyze all forms of matter, with little-to-no sample preparation, LIBS has many advantages over conventional atomic emission spectroscopy techniques. With the maturation of the technologies that make LIBS possible, there has been a growing movement to implement LIBS in portable analyzers for field applications. In particular, LIBS has long been considered the front-runner in the drive for stand-off detection of trace deposits of explosives. Thus there is a need for a better understanding of the relevant processes that are responsible for the LIBS signature and their relationships to the different system parameters that are helping to improve LIBS as a sensing technology. This study explores the use of LIBS as a method to detect random trace amounts of specific organic materials deposited on organic or non-metallic surfaces. This requirement forces the limitation of single-shot signal analysis. This study is both experimental and theoretical, with a sizeable component addressing data analysis using principal components analysis to reduce the dimensionality of the data, and quadratic discriminant analysis to classify the data. In addition, the alternative approach of 'target factor analysis' was employed to improve detection of organic residues on organic substrates. Finally, a new method of characterizing the laser-induced plasma of organics, which should lead to improved data collection and analysis, is introduced. The comparison between modeled and experimental measurements of plasma temperatures and electronic density is discussed in order to improve the present models of low-temperature laser induced plasmas.
Show less - Date Issued
- 2011
- Identifier
- CFE0003708, ucf:48843
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003708
- Title
- 7: AN INTERACTIVE INSTALLATION; EXPLORATIONS IN THE DIGITAL, THE SPIRITUAL, AND THE UNCANNY.
- Creator
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Lewter, Bradley, Peters, Phil, University of Central Florida
- Abstract / Description
-
This thesis explores the application of digital technologies in the creation of visionary or transformative artwork. The installation emphasizes number, color, symmetry, and the human form to create symbolic compositions patterned after ancient archetypes. Background research was done to inform the work through studies of the principles of visionary and transformative artwork as practiced by Ernst Fuchs, De Es Schwertberger, and Alex Grey. Connections between art and spirituality as explained...
Show moreThis thesis explores the application of digital technologies in the creation of visionary or transformative artwork. The installation emphasizes number, color, symmetry, and the human form to create symbolic compositions patterned after ancient archetypes. Background research was done to inform the work through studies of the principles of visionary and transformative artwork as practiced by Ernst Fuchs, De Es Schwertberger, and Alex Grey. Connections between art and spirituality as explained by Kandinsky were studied to augment these principles. The sequence of artwork within the installation is comprised of both digital paintings and interactive triptych panels. To convey a sense of the mystical or sacred, the Rothko Chapel was used to inform the installation and serve as an artistic precedent. As the interactive work is created using realistically-modeled, computer generated characters, special consideration was given to understanding the "uncanny valley" and its potential effect in the interpretation of the installation. Interactivity is achieved through the use of ultrasonic sensors and Arduino prototyping boards.
Show less - Date Issued
- 2010
- Identifier
- CFE0003314, ucf:48487
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003314
- Title
- Quantum Chemical Studies for the Engineering of Metal Organic Materials.
- Creator
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Rivera Jacquez, Hector, Masunov, Artem, Balaeff, Alexander, Harper, James, Heider, Emily, Zou, Shengli, Kaden, William, University of Central Florida
- Abstract / Description
-
Metal Organic Materials (MOM) are composed of transition metal ions as connectors and organic ligands as linkers. MOMs have been found to have high porosity, catalytic, and optical properties. Here we study the gas adsorption, color change, and non-linear optical properties of MOMs. These properties can be predicted using theoretical methods, and the results may provide experimentalists with guidance for rational design and engineering of novel MOMs. The theory levels used include semi...
Show moreMetal Organic Materials (MOM) are composed of transition metal ions as connectors and organic ligands as linkers. MOMs have been found to have high porosity, catalytic, and optical properties. Here we study the gas adsorption, color change, and non-linear optical properties of MOMs. These properties can be predicted using theoretical methods, and the results may provide experimentalists with guidance for rational design and engineering of novel MOMs. The theory levels used include semi-empirical quantum mechanical calculations with the PM7 Hamiltonian and, Density Functional Theory (DFT) to predict the geometry and electronic structure of the ground state, and Time Dependent DFT (TD-DFT) to predict the excited states and the optical properties.The molecular absorption capacity of aldoxime coordinated Zn(II) based MOMs (previously measured experimentally) is predicted by using PM7 Theory level. The 3D structures were optimized with and without host molecules inside the pores. The absorption capacity of these crystals was predicted to be 8H2 or 3N2 per unit cell. When going beyond this limit, the structural integrity of the bulk material becomes fractured and microcrystals are observed both experimentally and theoretically.The linear absorption properties of Co(II) based complexes are known to change color when the coordination number is altered. In order to understand the mechanism of this color change TD-DFT methods are employed. The chromic behavior of the Co(II) based complexes studied was confirmed to be due to a chain in coordination number that resulted in lower metal to ligand distances. These distances destabilize the occupied metal d orbitals, and as a consequence of this, the metal to ligand transition energy is lowered enough to allow the crystals to absorb light at longer wavelengths.Covalent organic frameworks (COFs) present an extension of MOM principles to the main group elements. The synthesis of ordered COFs is possible by using predesigned structures andcarefully selecting the building blocks and their conditions for assembly. The crystals formed by these systems often possess non-linear optical (NLO) properties. Second Harmonic Generation (SHG) is one of the most used optical processes. Currently, there is a great demand for materials with NLO optical properties to be used for optoelectronic, imaging, sensing, among other applications. DFT calculations can predict the second order hyperpolarizability ?2 and tensor components necessary to estimate NLO. These calculations for the ?2 were done with the use of the Berry's finite field approach. An efficient material with high ?2 was designed and the resulting material was predicted to be nearly fivefold higher than the urea standard.Two-photon absorption (2PA) is another NLO effect. Unlike SHG, it is not limited to acentric material and can be used development of in vivo bio-imaging agents for the brain. Pt(II) complexes with porphyrin derivatives are theoretically studied for that purpose. The mechanism of 2PA enhancement was identified. For the most efficient porphyrin, the large 2PA cross-section was found to be caused by a HOMO-LUMO+2 transition. This transition is strongly coupled to 1PA allowed Q-band HOMO-LUMO states by large transition dipoles. Alkyl carboxyl substituents delocalize the LUMO+2 orbital due to their strong ?-acceptor effect, enhancing transition dipoles and lowering the 2PA transition to the desirable wavelengths range.The mechanism 2PA cross-section enhancement of aminoxime and aldoxime ligands upon metal addition of is studied with TD-DFT methods. This mechanism of enhancement is found to be caused by the polarization of the ligand orbitals by the metal cation. After polarization an increase in ligand to ligand transition dipole moment. This enhancement of dipole moment is related to the increase in 2PA cross-sections.
Show less - Date Issued
- 2015
- Identifier
- CFE0005990, ucf:50777
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005990
- Title
- Physical-Virtual Patient Simulators: Bringing Tangible Humanity to Simulated Patients.
- Creator
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Daher, Salam, Welch, Gregory, Gonzalez, Laura, Cendan, Juan, Proctor, Michael, University of Central Florida
- Abstract / Description
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In lieu of real patients, healthcare educators frequently use simulated patients. Simulated patients can be realized in physical form, such as mannequins and trained human actors, or virtual form, such as via computer graphics presented on two-dimensional screens or head-mounted displays. Each of these alone has its strengths and weaknesses. I introduce a new class of physical-virtual patient (PVP) simulators that combine strengths of both forms by combining the flexibility and richness of...
Show moreIn lieu of real patients, healthcare educators frequently use simulated patients. Simulated patients can be realized in physical form, such as mannequins and trained human actors, or virtual form, such as via computer graphics presented on two-dimensional screens or head-mounted displays. Each of these alone has its strengths and weaknesses. I introduce a new class of physical-virtual patient (PVP) simulators that combine strengths of both forms by combining the flexibility and richness of virtual patients with tangible characteristics of a human-shaped physical form that can also exhibit a range of multi-sensory cues, including visual cues (e.g., capillary refill and facial expressions), auditory cues (e.g., verbal responses and heart sounds), and tactile cues (e.g., localized temperature and pulse). This novel combination of integrated capabilities can improve patient simulation outcomes. In my Ph.D. work I focus on three primary areas of related research. First, I describe the realization of the technology for PVPs and results from two user-studies to evaluate the importance of dynamic visuals and human-shaped physical form in terms of perception, behavior, cognition, emotions, and learning.Second, I present a general method to numerically evaluate the compatibility of any simulator-scenario pair in terms of importance and fidelity of cues. This method has the potential to make logistical, economic, and educational impacts on the choices of utilizing existing simulators.Finally, I describe a method for increasing human perception of simulated humans by exposing participants to the simulated human taking part in a short, engaging conversation prior to the simulation.
Show less - Date Issued
- 2018
- Identifier
- CFE0007750, ucf:52402
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007750
- Title
- Environmental Physical(-)Virtual Interaction to Improve Social Presence with a Virtual Human in Mixed Reality.
- Creator
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Kim, Kangsoo, Welch, Gregory, Gonzalez, Avelino, Sukthankar, Gita, Bruder, Gerd, Fiore, Stephen, University of Central Florida
- Abstract / Description
-
Interactive Virtual Humans (VHs) are increasingly used to replace or assist real humans in various applications, e.g., military and medical training, education, or entertainment. In most VH research, the perceived social presence with a VH, which denotes the user's sense of being socially connected or co-located with the VH, is the decisive factor in evaluating the social influence of the VH(-)a phenomenon where human users' emotions, opinions, or behaviors are affected by the VH. The purpose...
Show moreInteractive Virtual Humans (VHs) are increasingly used to replace or assist real humans in various applications, e.g., military and medical training, education, or entertainment. In most VH research, the perceived social presence with a VH, which denotes the user's sense of being socially connected or co-located with the VH, is the decisive factor in evaluating the social influence of the VH(-)a phenomenon where human users' emotions, opinions, or behaviors are affected by the VH. The purpose of this dissertation is to develop new knowledge about how characteristics and behaviors of a VH in a Mixed Reality (MR) environment can affect the perception of and resulting behavior with the VH, and to find effective and efficient ways to improve the quality and performance of social interactions with VHs. Important issues and challenges in real(-)virtual human interactions in MR, e.g., lack of physical(-)virtual interaction, are identified and discussed through several user studies incorporating interactions with VH systems. In the studies, different features of VHs are prototyped and evaluated, such as a VH's ability to be aware of and influence the surrounding physical environment, while measuring objective behavioral data as well as collecting subjective responses from the participants. The results from the studies support the idea that the VH's awareness and influence of the physical environment can improve not only the perceived social presence with the VH, but also the trustworthiness of the VH within a social context. The findings will contribute towards designing more influential VHs that can benefit a wide range of simulation and training applications for which a high level of social realism is important, and that can be more easily incorporated into our daily lives as social companions, providing reliable relationships and convenience in assisting with daily tasks.
Show less - Date Issued
- 2018
- Identifier
- CFE0007340, ucf:52115
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007340
- Title
- Semiconductor Design and Manufacturing Interplay to Achieve Higher Yields at Reduced Costs using SMART Techniques.
- Creator
-
Oberai, Ankush Bharati, Yuan, Jiann-Shiun, Abdolvand, Reza, Georgiopoulos, Michael, Sundaram, Kalpathy, Reilly, Charles, University of Central Florida
- Abstract / Description
-
Since the outset of IC Semiconductor market there has been a gap between its design and manufacturing communities. This gap continued to grow as the device geometries started to shrink and the manufacturing processes and tools got more complex. This gap lowered the manufacturing yield, leading to higher cost of ICs and delay in their time to market. It also impacted performance of the ICs, impacting the overall functionality of the systems they were integrated in. However, in the recent years...
Show moreSince the outset of IC Semiconductor market there has been a gap between its design and manufacturing communities. This gap continued to grow as the device geometries started to shrink and the manufacturing processes and tools got more complex. This gap lowered the manufacturing yield, leading to higher cost of ICs and delay in their time to market. It also impacted performance of the ICs, impacting the overall functionality of the systems they were integrated in. However, in the recent years there have been major efforts to bridge the gap between design and manufacturing using software solutions by providing closer collaborations techniques between design and manufacturing communities. The root cause of this gap is inherited by the difference in the knowledge and skills required by the two communities. The IC design community is more microelectronics, electrical engineering and software driven whereas the IC manufacturing community is more driven by material science, mechanical engineering, physics and robotics. The cross training between the two is almost nonexistence and not even mandated. This gap is deemed to widen, with demand for more complex designs and miniaturization of electronic appliance-products. Growing need for MEMS, 3-D NANDS and IOTs are other drivers that could widen the gap between design and manufacturing. To bridge this gap, it is critical to have close loop solutions between design and manufacturing This could be achieved by SMART automation on both sides by using Artificial Intelligence, Machine Learning and Big Data algorithms. Lack of automation and predictive capabilities have even made the situation worse on the yield and total turnaround times. With the growing fabless and foundry business model, bridging the gap has become even more critical. Smart Manufacturing philosophy must be adapted to make this bridge possible. We need to understand the Fab-fabless collaboration requirements and the mechanism to bring design to the manufacturing floor for yield improvement. Additionally, design community must be educated with manufacturing process and tool knowledge, so they can design for improved manufacturability. This study will require understanding of elements impacting manufacturing on both ends of the design and manufacturing process. Additionally, we need to understand the process rules that need to be followed closely in the design phase. Best suited SMART automation techniques to bridge the gap need to be studied and analyzed for their effectiveness.
Show less - Date Issued
- 2018
- Identifier
- CFE0007351, ucf:52096
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007351
- Title
- Beauty and the Beast: The Attractiveness Bias in an Online Peer Mentoring Program.
- Creator
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Garcia, Carollaine, Jentsch, Kimberly, Jentsch, Florian, Fritzsche, Barbara, Burke, Shawn, University of Central Florida
- Abstract / Description
-
The bias against attractiveness is fairly implicit and furthermore, powerfully impacts people's subsequent impressions of and behaviors toward others (Cash, Gillen, (&) Burns, 1977; Dion et al., 1972). Pallet, Link and Lee (2010) examined the effect of various facial spatial configurations on attractiveness and found that raters rated faces as most attractive when the eye-to-mouth ratio approximated 36% of the face length (the "golden ratio"), which coincides with the measurements of an...
Show moreThe bias against attractiveness is fairly implicit and furthermore, powerfully impacts people's subsequent impressions of and behaviors toward others (Cash, Gillen, (&) Burns, 1977; Dion et al., 1972). Pallet, Link and Lee (2010) examined the effect of various facial spatial configurations on attractiveness and found that raters rated faces as most attractive when the eye-to-mouth ratio approximated 36% of the face length (the "golden ratio"), which coincides with the measurements of an average and thus more attractive face. The present study examined the extent to which the distance of these objectively measured facial features affected mentors' perceptions of their prot(&)#233;g(&)#233;s, the subsequent mentoring given to them, and the prot(&)#233;g(&)#233;s' own behavior (e.g. seek feedback, request specific information).The gender composition of the mentor-prot(&)#233;g(&)#233; dyad was expected to moderate these relationships. I also examined whether, given the expected effects of facial measurements, withholding access to visual cues would affect mentor perceptions and behavior. Participants were 118 mentor/prot(&)#233;g(&)#233; dyads from a large Southeastern university who volunteered to participate in a formal online peer mentoring program. After seeing their prot(&)#233;g(&)#233;s' profiles (and for those in the experimental condition, a picture), mentors chatted with their prot(&)#233;g(&)#233;s once a week for 30 minutes for a total of 4 weeks. Results indicated that prot(&)#233;g(&)#233;s with facial features moderately distant from the golden ratio were perceived as more similar by mentors in same-gender dyads and received greater mentoring than did prot(&)#233;g(&)#233;s closest and farthest from the golden ratio. In opposite-gender dyads, however, mentors reported greater similarity toward those that were farthest from the golden ratio but provided the greatest mentoring to those closest to the golden ratio. The relationship between facial measurements and prot(&)#233;g(&)#233; proactivity was moderated by whether or not their mentor had access to their picture. While prot(&)#233;g(&)#233;s closest to the ratio were more proactive in the picture condition, those that were farthest from it were more proactive in the non-picture condition. Proactivity was as expected associated with greater levels of mentoring, which was ultimately related to a more fulfilled and beneficial relationship for prot(&)#233;g(&)#233;s (i.e. less stress, greater self-efficacy and satisfaction). The results of this study indicate that facial measurements are associated with both differences in mentor and in prot(&)#233;g(&)#233; behavior and that the specific nature of these relationships differs as a function of gender composition. Implications for practice and theory will be discussed.
Show less - Date Issued
- 2012
- Identifier
- CFE0004504, ucf:49275
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004504
- Title
- The effects of four weeks of high intensity interval training and (&)#223;-hydroxy-(&)#223;-methylbutyric free acid on the onset of neuromuscular fatigue.
- Creator
-
Miramonti, Amelia, Stout, Jeffrey, Hoffman, Jay, Fukuda, David, University of Central Florida
- Abstract / Description
-
This study investigated the effects of high intensity interval training (HIIT) and ?-hydroxy-?-methylbutyric free acid (HMBFA) on the onset of neuromuscular fatigue in healthy young men and women. Thirty-seven subjects (22 men and 15 women; mean (&)#177; SD age = 22.8 (&)#177; 3.4yrs) completed an incremental cycle ergometer test (GXT) to exhaustion. During the GXT, electromyography (EMG) signals from the right vastus lateralis were recorded to determine the power output at the onset of...
Show moreThis study investigated the effects of high intensity interval training (HIIT) and ?-hydroxy-?-methylbutyric free acid (HMBFA) on the onset of neuromuscular fatigue in healthy young men and women. Thirty-seven subjects (22 men and 15 women; mean (&)#177; SD age = 22.8 (&)#177; 3.4yrs) completed an incremental cycle ergometer test (GXT) to exhaustion. During the GXT, electromyography (EMG) signals from the right vastus lateralis were recorded to determine the power output at the onset of neuromuscular fatigue (PWCFT), and peak wattage was used to assign individual training loads.After baseline testing (PRE), subjects were randomly assigned to one of three groups: control (C, n = 9), training with placebo (P, n = 14), or training with supplementation (S, n = 14). Subjects assigned to P and S completed 12 HIIT sessions over 4 weeks while subjects assigned to C were asked to maintain their normal diet and activity patterns. After 4 weeks, subjects returned for post-testing (POST). The PWCFT values (W) were determined using a DMAX method. The EMG amplitude root mean square ((&)#181;Vrms) values were used to generate a third-order polynomial regression (3PR) representing the increase in (&)#181;Vrms versus time of the GXT. The onset of fatigue (TF) was defined as the x-value (time, s) of the point on the 3PR that measured the maximal perpendicular distance from the line between the first and last data points. TF was used to estimate PWCFT according to the equation: PWCFT = PO + a ? (n/N), where PO is the power output of the stage in which TF occurred, a is the increment in power output between GXT stages (25W), n is the difference (s) between TF and the beginning of the stage during which TF occurred, and N is the duration of a stage (120s).A two-way repeated measures ANOVA was used to identify group (&)#215; time interaction for PWCFT. If a significant interaction occurred, one-way factorial ANOVAs were used. Fisher's least significant difference post hoc comparisons were performed between groups. If a significant main effect occurred, dependent samples t-tests with Bonferroni corrections (p = [0.05/3] = 0.017) were performed across time for each group.The two-way ANOVA resulted in a significant interaction (F = 6.69, p = 0.004). Follow-up analysis with one-way ANOVA resulted in no difference among groups at PRE (F = 0.87, p = 0.43), however a significant difference was shown for POST values (F = 5.46, p = 0.009). Post-hoc analysis among POST values showed significant differences between S and both P (p = 0.034) and C (p = 0.003). No differences (p = 0.226) were noted between P and C. Paired samples t-tests detected significant changes following HIIT for S (p (<) 0.001) and P (p = 0.016), but no change in C (p = 0.473).Results of this study indicate that HIIT was effective in delaying the onset of fatigue, but supplementation with HMBFA in conjunction with HIIT was more effective than HIIT alone. An increase in PWCFT represents an increase in the maximal power output an individual can sustain without eliciting fatigue. Therefore, HIIT can be used to improve performance in both endurance activities as well as intermittent sports. In addition, HMBFA supplementation is a simple method that can be used to maximize the benefits of HIIT.Acknowledgments: Metabolic Technologies, Inc. provided the supplement and funding for this study.
Show less - Date Issued
- 2015
- Identifier
- CFE0006043, ucf:50968
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006043