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Title: Fast Compressed Automatic Target Recognition for a Compressive Infrared Imager.
Creator: Millikan, Brian, Foroosh, Hassan, Rahnavard, Nazanin, Muise, Robert, Atia, George, Mahalanobis, Abhijit, Sun, Qiyu, University of Central Florida
Abstract / Description: Many military systems utilize infrared sensors which allow an operator to see targets at night. Several of these are either mid-wave or long-wave high resolution infrared sensors, which are expensive to manufacture. But compressive sensing, which has primarily been demonstrated in medical applications, can be used to minimize the number of measurements needed to represent a high-resolution image. Using these techniques, a relatively low cost mid-wave infrared sensor can be realized which has...
Show moreMany military systems utilize infrared sensors which allow an operator to see targets at night. Several of these are either mid-wave or long-wave high resolution infrared sensors, which are expensive to manufacture. But compressive sensing, which has primarily been demonstrated in medical applications, can be used to minimize the number of measurements needed to represent a high-resolution image. Using these techniques, a relatively low cost mid-wave infrared sensor can be realized which has a high effective resolution. In traditional military infrared sensing applications, like targeting systems, automatic targeting recognition algorithms are employed to locate and identify targets of interest to reduce the burden on the operator. The resolution of the sensor can increase the accuracy and operational range of a targeting system. When using a compressive sensing infrared sensor, traditional decompression techniques can be applied to form a spatial-domain infrared image, but most are iterative and not ideal for real-time environments. A more efficient method is to adapt the target recognition algorithms to operate directly on the compressed samples. In this work, we will present a target recognition algorithm which utilizes a compressed target detection method to identify potential target areas and then a specialized target recognition technique that operates directly on the same compressed samples. We will demonstrate our method on the U.S. Army Night Vision and Electronic Sensors Directorate ATR Algorithm Development Image Database which has been made available by the Sensing Information Analysis Center.
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Date Issued: 2018
Identifier: CFE0007408, ucf:52739
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007408

Title: VIBROTACTILE GUIDANCE CUES FOR TARGET IDENTIFICATION.
Creator: Downs, Joshua, Gilson, Richard, University of Central Florida
Abstract / Description: The purpose of this dissertation was to establish how vibrotactile guidance cues can be used to improve marksmanship. This work originated in an effort to provide covert communication, navigation, and weapon aiming cues for infantrymen. It is predominantly an application-driven investigation rather than driven a priori by specific theoretical predictions from models of human performance. Three experiments are presented. Experiment 1 established the affect on initial response to vibrotactile...
Show moreThe purpose of this dissertation was to establish how vibrotactile guidance cues can be used to improve marksmanship. This work originated in an effort to provide covert communication, navigation, and weapon aiming cues for infantrymen. It is predominantly an application-driven investigation rather than driven a priori by specific theoretical predictions from models of human performance. Three experiments are presented. Experiment 1 established the affect on initial response to vibrotactile guidance cues of tactor placements on the palmer versus dorsal surface of the hand, and targets appearing left versus right of center. Results suggest that tactile cues provided on the left side of the medial line of the hand afford moving the hand to the left, while tactile cues provided on the right side of the medial line afford moving the hand to the right. Experiment 2 established the affect of continuous relative distance cues and on- versus off-target vibrotactile stimuli on reaction time and accuracy for target selection. Results indicated an interaction between the pulse rate of vibrotactile stimuli and the method used to highlight an "on-target" condition; the suppressed target condition was superior to the enhanced target condition when the pulse rate increased as the cursor moved closer to a target. Experiment 3 established if there are performance differences between discrete and continuous distance information for target selection, and investigated the interaction between the near-target pulse rate and on-target cues. Results indicate that maximizing the difference between near-target guidance cues and on-target cues reduces the target selection time, particularly when the near-target pulse rates are fast (ISI = 10 msec). The results also suggest that, as with vision, the vibrotactile off-target guidance cues are not necessary during the whole target selection task. Rather, the guidance cues can be provided only during the initial pop-up condition and during the sub-movements closing on the target.
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Date Issued: 2005
Identifier: CFE0000369, ucf:46333
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000369

Title: WHEN TO STRIKE: EXPLORING THE VARIABLES THAT LEAD TO SUCCESSFUL DECAPITATION STRIKES.
Creator: Pierres, Renzo, Boutton, Andrew, University of Central Florida
Abstract / Description: The purpose of this thesis is to determine how different variables can affect a terrorist group's reaction to a targeted leadership strike, known as a decapitation strike. Decapitation strikes often produce unwanted results, such as a splintering of the terrorist group, or a failure to destroy the group. It is important that we understand which variables can lead to a group's destruction after a decapitation strike, to maximize the decapitation's effectiveness. In my research I have...
Show moreThe purpose of this thesis is to determine how different variables can affect a terrorist group's reaction to a targeted leadership strike, known as a decapitation strike. Decapitation strikes often produce unwanted results, such as a splintering of the terrorist group, or a failure to destroy the group. It is important that we understand which variables can lead to a group's destruction after a decapitation strike, to maximize the decapitation's effectiveness. In my research I have determined that group size, group ideological extremism, and the role of the leader targeted all have a substantial impact on the success of the decapitation strike. Using these three variables, I will examine three groups which have varying size, extremism, and leadership, and determine whether the decapitation strikes were successful and how these variables affected the results.
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Date Issued: 2019
Identifier: CFH2000488, ucf:45848
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000488

Title: DEVELOPMENT OF A MOTOR SPEED CONTROL SYSTEM USING MATLAB AND SIMULINK, IMPLEMENTED WITH A DIGITAL SIGNAL PROCESSOR.
Creator: Klee, Andrew, Weeks, Arthur, University of Central Florida
Abstract / Description: This thesis describes an improved methodology for embedded software development. MATLAB and Simulink allow engineers to simplify algorithm development and avoid duplication of effort in deploying these algorithms to the end hardware. Special new hardware targeting capabilities of MATLAB and Simulink are described in detail. A motor control system design served to demonstrate the efficacy of this new method. Initial data was collected to help model the motor in Simulink. This allowed for the...
Show moreThis thesis describes an improved methodology for embedded software development. MATLAB and Simulink allow engineers to simplify algorithm development and avoid duplication of effort in deploying these algorithms to the end hardware. Special new hardware targeting capabilities of MATLAB and Simulink are described in detail. A motor control system design served to demonstrate the efficacy of this new method. Initial data was collected to help model the motor in Simulink. This allowed for the design of the open and closed loop control systems. The designed system was very effective, with good response and no steady state error. The entire design process and deployment to a digital signal processor took significantly less time and effort than other typical methods. The results of the control system design as well as the details of these development improvements are described.
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Date Issued: 2005
Identifier: CFE0000477, ucf:46367
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000477

Title: Folate conjugated hyperbranched polyester nanoparticles for prostate tumor-targeted delivery of a cytotoxic peptide via prostate specific membrane antigen.
Creator: Flores-Fernandez, Orielyz, Perez Figueroa, J. Manuel, Campiglia, Andres, Yestrebsky, Cherie, Harper, James, Khaled, Annette, University of Central Florida
Abstract / Description: Prostate Cancer is the second most deadly cancer in men, after lung cancer. The need for new and effective therapeutics that can constrain prostate cancer progression are challenged by the lack of suitable delivery strategies that target prostate cancer tissue. To study CT20p as potential chemotherapeutic agent in the treatment of prostate cancer we proposed the use of targetable hyperbranched polyester (HBPE) based nanoparticles as delivery system. Folic acid was conjugated to the...
Show moreProstate Cancer is the second most deadly cancer in men, after lung cancer. The need for new and effective therapeutics that can constrain prostate cancer progression are challenged by the lack of suitable delivery strategies that target prostate cancer tissue. To study CT20p as potential chemotherapeutic agent in the treatment of prostate cancer we proposed the use of targetable hyperbranched polyester (HBPE) based nanoparticles as delivery system. Folic acid was conjugated to the nanocarrier to improve the selectivity of the nanoparticle towards specific cell surface targets in prostate cancer cell lines. Specifically we evaluated LNCaP that up-regulated the PSMA receptor. The synthesis of folate conjugated hyperbranched polyester nanoparticles was accomplished using an aliphatic and biodegradable hyperbranched polyester (HBPE). HBPE was prepared from commercially available diethyl malonate and 4-bromobutyl acetate. Our AB2 type monomer displays a three-bond connectivity that grows three-dimensionally under specific polymerization conditions. The product, HBPE, is a polymer with globular configuration that contains surface carboxylic acid groups and holds hydrophobic cavities. Carboxylated HBPE nanoparticles were synthesized via solvent diffusion method. A variety of hydrophobic cargos including: dyes (DiR and DiI) and the cytotoxic peptide CT20p were successfully encapsulated. DLS along with STEM imaging reveal nanoparticle preparations with ~100 nm size. Using water-soluble carbodiimide chemistry, surface modifications were accomplished. Available carboxylic acid groups were conjugated to aminated folic acid to yield folate functionalized nanoparticles.We explore the targeting capability of the Folate-HBPE nanoparticles and demonstrated that the cell internalization of Folate-HBPE into prostate cancer cell lines (LNCaP and PSMA (+) PC-3) was attained via a PSMA-mediated targeting mechanism. Furthermore, when CT20p was delivered to PSMA expressing PCa cells, detachment and death was observed; together with a reduction in the levels of ?1 integrin (CD29) expression, an integrin implicate in cell communication and cell adhesion. CT20p inhibits cell proliferation within 24 h and produce significant cell death after 48 h post treatment. The IC50 of CT20p was calculated at ~7 nM. Additionally, we investigated the capability of Folate-HBPE(CT20p) to perform as a therapeutic agent, in an in vivo setup, using a murine prostate tumor model. The Folate-PEG-HBPE NPs protected CT20p while in circulation and allowed effective uptake by PSMA-mediated targeting. Treatment with Folate-HBPE(CT20p) display localize tumor targeting and significant tumor growth inhibition in PSMA(+) PCa cell lines within days. Together these results suggest the potential of Folate-HBPE(CT20p) nanoparticles in the treatment of prostate cancer.
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Date Issued: 2015
Identifier: CFE0006216, ucf:51112
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006216

Title: Do multiple conditions elicit the visual redundant signals effect in simple response times?.
Creator: Mishler, Ada, Neider, Mark, Lighthall, Nichole, Szalma, James, Joseph, Dana, University of Central Florida
Abstract / Description: The redundant signals effect, or redundancy gain, is an increase in human processing efficiency when target redundancy is introduced into a display. An advantage for two visual signals over one has been found in a wide variety of speeded response time tasks, but does not always occur and may be weakened by some task parameters. These disparate results suggest that visual redundancy gain is not a unitary effect, but is instead based on different underlying mechanisms in different tasks. The...
Show moreThe redundant signals effect, or redundancy gain, is an increase in human processing efficiency when target redundancy is introduced into a display. An advantage for two visual signals over one has been found in a wide variety of speeded response time tasks, but does not always occur and may be weakened by some task parameters. These disparate results suggest that visual redundancy gain is not a unitary effect, but is instead based on different underlying mechanisms in different tasks. The current study synthesizes previous theories applied to redundancy gain into the three-conditions hypothesis, which states that visual redundancy gain depends on the presence of at least one of three factors: visual identicalness between multiple targets, familiarity with multiple similar targets, or prepotentiation for multiple different targets. In a series of four simple response time experiments, participants responded to single targets presented to one side of the visual field, or to bilateral targets presented to both sides of the visual field. The first three experiments each explored one condition, the first experiment by comparing identical to non-identical random shapes to examine visual identicalness, the second by comparing familiar to unfamiliar letters to examine familiarity, and the third by comparing previewed with non-previewed random shapes to examine prepotentiation. Finally, the fourth experiment employed letters that varied in familiarity, identicalness, and preview, to examine whether or not the three hypothesized causes have multiplicative effects on redundancy. Results indicated that participants were able to benefit equally from redundancy regardless of identicalness, familiarity, or prepotentiation, but that they did so by ignoring one target in the redundant-target trials. These results suggest that redundancy gain may need to be even further divided into more than three underlying mechanisms, with a serial processing mechanism that can be used for stimuli that are not familiar, prepotentiated, or identical.
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Date Issued: 2017
Identifier: CFE0006899, ucf:52890
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006899

Title: PREDICTING MERGERS AND ACQUISITIONS.
Creator: D'Angelo, John, Gilkeson, Jim, University of Central Florida
Abstract / Description: Being able to predict a merger or acquisition before it takes place could lead to an investor earning a premium, if they owned shares of the targeted firm before the merger or acquisition attempt is announced. On average acquiring firms pay a premium when acquiring or merging with a targeted firm. This study uses publicly available financial information for 7,267 attempted takeover targets and 52,343 non-targeted firms for the period January 3, 2000 through December 31, 2007 to estimate ...
Show moreBeing able to predict a merger or acquisition before it takes place could lead to an investor earning a premium, if they owned shares of the targeted firm before the merger or acquisition attempt is announced. On average acquiring firms pay a premium when acquiring or merging with a targeted firm. This study uses publicly available financial information for 7,267 attempted takeover targets and 52,343 non-targeted firms for the period January 3, 2000 through December 31, 2007 to estimate (using logit) predictive models. Financial ratios are constructed based on six hypotheses found in the literature. Although statistical evidence supports a few of the hypotheses, the low predictive power of the models does not indicate the ability to accurately predict targeted firms ahead of time, let alone with any economic significance.
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Date Issued: 2012
Identifier: CFH0004133, ucf:44892
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004133

Title: EFFICIENT ALGORITHMS FOR CORRELATION PATTERN RECOGNITION.
Creator: Ragothaman, Pradeep, Mikhael, Wasfy, University of Central Florida
Abstract / Description: The mathematical operation of correlation is a very simple concept, yet has a very rich history of application in a variety of engineering fields. It is essentially nothing but a technique to measure if and to what degree two signals match each other. Since this is a very basic and universal task in a wide variety of fields such as signal processing, communications, computer vision etc., it has been an important tool. The field of pattern recognition often deals with the task of analyzing...
Show moreThe mathematical operation of correlation is a very simple concept, yet has a very rich history of application in a variety of engineering fields. It is essentially nothing but a technique to measure if and to what degree two signals match each other. Since this is a very basic and universal task in a wide variety of fields such as signal processing, communications, computer vision etc., it has been an important tool. The field of pattern recognition often deals with the task of analyzing signals or useful information from signals and classifying them into classes. Very often, these classes are predetermined, and examples (templates) are available for comparison. This task naturally lends itself to the application of correlation as a tool to accomplish this goal. Thus the field of Correlation Pattern Recognition has developed over the past few decades as an important area of research. From the signal processing point of view, correlation is nothing but a filtering operation. Thus there has been a great deal of work in using concepts from filter theory to develop Correlation Filters for pattern recognition. While considerable work has been to done to develop linear correlation filters over the years, especially in the field of Automatic Target Recognition, a lot of attention has recently been paid to the development of Quadratic Correlation Filters (QCF). QCFs offer the advantages of linear filters while optimizing a bank of these simultaneously to offer much improved performance. This dissertation develops efficient QCFs that offer significant savings in storage requirements and computational complexity over existing designs. Firstly, an adaptive algorithm is presented that is able to modify the QCF coefficients as new data is observed. Secondly, a transform domain implementation of the QCF is presented that has the benefits of lower computational complexity and computational requirements while retaining excellent recognition accuracy. Finally, a two dimensional QCF is presented that holds the potential to further save on storage and computations. The techniques are developed based on the recently proposed Rayleigh Quotient Quadratic Correlation Filter (RQQCF) and simulation results are provided on synthetic and real datasets.
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Date Issued: 2007
Identifier: CFE0001974, ucf:47429
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001974

Title: RADIATION STUDIES OF THE TIN-DOPED MICROSCOPIC DROPLET LASER PLASMA LIGHT SOURCE SPECIFIC TO EUV LITHOGRAPHY.
Creator: Koay, Chiew-Seng, Richardson, Martin, University of Central Florida
Abstract / Description: Extreme ultraviolet lithography(EUVL) is being developed worldwide as the next generation technology to be inserted in ~ 2009 for the mass production of IC chips with feature sizes
Show moreExtreme ultraviolet lithography(EUVL) is being developed worldwide as the next generation technology to be inserted in ~ 2009 for the mass production of IC chips with feature sizes <35 nm. One major challenge to its implementation is the development of a 13.5 nm EUV source of radiation that meets the requirements of current roadmap designs of the source of illumination in commercial EUVL scanners. The light source must be debris-free, in a free-space environment with the imaging EUV optics that must provide sufficient, narrow spectral band EUV power to print 100 wafers/hr. To meet this need, extensive studies on emission from a laser plasma source utilizing tin-doped droplet target was conducted. Presented in this work, are the many optical techniques such as spectroscopy, radiometry, and imaging, that were employed to characterize and optimize emission from the laser plasma source State of the art EUV spectrographs were employed to observe the source's spectrum under various laser irradiation conditions. Comparing the experimental spectra to those from theory, has allowed the determination of the Sn ion stages responsible for emitting into the useful EUV bandwidth. Experimental results were compared to spectral simulations obtained using Collisional-Radiative Equilibrium (CRE) model, as well. Moreover, extensive measurements surveying source emission from 2 nm to 30 nm, which is the region of the electromagnetic spectrum defined as EUV, was accomplished. Absolutely calibrated metrology was employed with the Flying Circus instrument from which the source's conversion efficiency (CE)--from laser to the useful EUV energy--was characterized under various laser irradiation conditions. Hydrodynamic simulations of the plasma expansion together with the CRE model predicted the condition at which optimum conversion could be attained. The condition was demonstrated experimentally, with the highest CE to be slightly above 2%, which is the highest value among all EUV source contenders. In addition to laser intensity, the CE was found to depend on the laser wavelength. For better understanding, this observation is compared to results from simulations. Through a novel approach in imaging, the size of the plasma was characterized by recording images of the plasma within a narrow band, around 13.5 nm. The size, approximately 100 ìm, is safely within the etendue limit set by the optical elements in the EUV scanner. Finally, the notion of irradiating the target with multiple laser beams was explored for the possibility of improving the source's conversion efficiency.
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Date Issued: 2006
Identifier: CFE0000938, ucf:46733
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000938

Title: Human Action Detection, Tracking and Segmentation in Videos.
Creator: Tian, Yicong, Shah, Mubarak, Bagci, Ulas, Liu, Fei, Walker, John, University of Central Florida
Abstract / Description: This dissertation addresses the problem of human action detection, human tracking and segmentation in videos. They are fundamental tasks in computer vision and are extremely challenging to solve in realistic videos. We first propose a novel approach for action detection by exploring the generalization of deformable part models from 2D images to 3D spatiotemporal volumes. By focusing on the most distinctive parts of each action, our models adapt to intra-class variation and show robustness to...
Show moreThis dissertation addresses the problem of human action detection, human tracking and segmentation in videos. They are fundamental tasks in computer vision and are extremely challenging to solve in realistic videos. We first propose a novel approach for action detection by exploring the generalization of deformable part models from 2D images to 3D spatiotemporal volumes. By focusing on the most distinctive parts of each action, our models adapt to intra-class variation and show robustness to clutter. This approach deals with detecting action performed by a single person. When there are multiple humans in the scene, humans need to be segmented and tracked from frame to frame before action recognition can be performed. Next, we propose a novel approach for multiple object tracking (MOT) by formulating detection and data association in one framework. Our method allows us to overcome the confinements of data association based MOT approaches, where the performance is dependent on the object detection results provided at input level. We show that automatically detecting and tracking targets in a single framework can help resolve the ambiguities due to frequent occlusion and heavy articulation of targets. In this tracker, targets are represented by bounding boxes, which is a coarse representation. However, pixel-wise object segmentation provides fine level information, which is desirable for later tasks. Finally, we propose a tracker that simultaneously solves three main problems: detection, data association and segmentation. This is especially important because the output of each of those three problems are highly correlated and the solution of one can greatly help improve the others. The proposed approach achieves more accurate segmentation results and also helps better resolve typical difficulties in multiple target tracking, such as occlusion, ID-switch and track drifting.
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Date Issued: 2018
Identifier: CFE0007378, ucf:52069
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007378

Title: REACTIVE CONTROL OF AUTONOMOUS DYNAMICAL SYSTEMS.
Creator: Chunyu, Jiangmin, Qu, Zhihua, University of Central Florida
Abstract / Description: This thesis mainly consists of five independent papers concerning the reactive control design of autonomous mobile robots in the context of target tracking and cooperative formation keeping with obstacle avoidance in the static/dynamic environment. Technical contents of this thesis are divided into three parts. The first part consists of the first two papers, which consider the target-tracking and obstacle avoidance in the static environment. Especially, in the static environment, a...
Show moreThis thesis mainly consists of five independent papers concerning the reactive control design of autonomous mobile robots in the context of target tracking and cooperative formation keeping with obstacle avoidance in the static/dynamic environment. Technical contents of this thesis are divided into three parts. The first part consists of the first two papers, which consider the target-tracking and obstacle avoidance in the static environment. Especially, in the static environment, a fundamental issue of reactive control design is the local minima problem (LMP) inherent in the potential field methods (PFMs). Through introducing a state-dependent planned goal, the first paper proposes a switching control strategy to tackle this problem. The control law for the planned goal is presented. When trapped into local minima, the robot can escape from local minima by following the planned goal. The proposed control law also takes into account the presence of possible saturation constraints. In addition, a time-varying continuous control law is proposed in the second paper to tackle this problem. Challenges of finding continuous control solutions of LMP are discussed and explicit design strategies are then proposed. The second part of this thesis deals with target-tracking and obstacle avoidance in the dynamic environment. In the third paper, a reactive control design is presented for Omni-directional mobile robots with limited sensor range to track targets while avoiding static and moving obstacles in a dynamically evolving environment. Towards this end, a multi-objective control problem is formulated and control is synthesized by generating a potential field force for each objective and combining them through analysis and design. Different from standard potential field methods, the composite potential field described in this paper is time-varying and planned to account for moving obstacles and vehicle motion. In order to accommodate a larger class of mobile robots, the fourth paper proposes a reactive control design for unicycle-type mobile robots. With the relative motion among the mobile robot, targets, and obstacles being formulated in polar coordinates, kinematic control laws achieving target-tracking and obstacle avoidance are synthesized using Lyapunov based technique, and more importantly, the proposed control laws also take into account possible kinematic control saturation constraints. The third part of this thesis investigates the cooperative formation control with collision avoidance. In the fifth paper, firstly, the target tracking and collision avoidance problem for a single agent is studied. Instead of directly extending the single agent controls to the multi-agents case, the single agent controls are incorporated with an existing cooperative control design. The proposed decentralized control is reactive, considers the formation feedback and changes in the communication networks. The proposed control is based on a potential field method; its inherent oscillation problem is also studied to improve group transient performance.
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Date Issued: 2010
Identifier: CFE0003421, ucf:48384
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003421

Title: Determinants of Terrorist Target Selection: A Quantitative Analysis.
Creator: Haywood, Taylor, Handberg, Roger, Dolan, Thomas, Boutton, Andrew, Vasquez, Joseph, University of Central Florida
Abstract / Description: Existing research on the subject of terrorism is vast, spanning causes of terrorism, the membership of terrorist groups, types of terrorist attacks, and more. One area of terrorism research, though, has received only limited consideration: terrorist target selection. What research does exist explains target selection almost exclusively as a function of ideology (Asal et al. 2009, 270 and 274; Drake 1998b, 54-56 and 58). However, such a limited causal focus obscures other possible, and...
Show moreExisting research on the subject of terrorism is vast, spanning causes of terrorism, the membership of terrorist groups, types of terrorist attacks, and more. One area of terrorism research, though, has received only limited consideration: terrorist target selection. What research does exist explains target selection almost exclusively as a function of ideology (Asal et al. 2009, 270 and 274; Drake 1998b, 54-56 and 58). However, such a limited causal focus obscures other possible, and probable, explanations of terrorist target selection. This paper proposes an alternative explanation of terrorist target selection that includes ideological and terrorist group capability variables, as well as a variable measuring the security levels in the geographic areas in which terrorist attacks take place. A research design employing multiple ordinary least squares regression is utilized. The findings demonstrate the importance of the independent variables, as well as the significance of the effects of the two-way and three-way interactions of variables from the three categories. Furthermore, the multiple regression models explain a greater percentage of the effects of the independent variables on the percentage of attacks against civilian targets when the three-way interaction variable is included than when this interaction variable is not included. From these findings, two primary policy implications are derived.
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Date Issued: 2017
Identifier: CFE0006744, ucf:51853
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006744

Title: Target validation for Neurofibromatosis Type 2 therapeutics.
Creator: Petrilli Guinart, Alejandra, Fernandez-Valle, Cristina, Altomare, Deborah, Khaled, Annette, Lambert, Stephen, University of Central Florida
Abstract / Description: Neurofibromatosis type 2 (NF2) is a benign tumor disease of the nervous system. Development of bilateral vestibular schwannomas is characteristic of NF2; however patients frequently present schwannomas on other nerves, as well as meningiomas and ependymomas. Currently, there are no drug therapies for NF2. There is an urgent need for development of NF2 therapeutics and this dissertation presents two independent potential therapeutic targets.The disease is caused by mutations in the NF2 gene...
Show moreNeurofibromatosis type 2 (NF2) is a benign tumor disease of the nervous system. Development of bilateral vestibular schwannomas is characteristic of NF2; however patients frequently present schwannomas on other nerves, as well as meningiomas and ependymomas. Currently, there are no drug therapies for NF2. There is an urgent need for development of NF2 therapeutics and this dissertation presents two independent potential therapeutic targets.The disease is caused by mutations in the NF2 gene that encodes a tumor suppressor called merlin. Loss of merlin function is associated with increased activity of Rac and p21-activated kinases (PAK) and deregulation of cytoskeletal organization. LIM domain kinases (LIMK1 and 2) are substrates for Cdc42/Rac-PAK, and modulate actin dynamics by phosphorylating cofilin, an actin severing and depolymerizing agent. LIMKs also translocate into the nucleus and regulate cell cycle progression. Here we report that mouse Schwann cells (MSCs) in which merlin function is lost as a result of Nf2 exon2 deletion (Nf2 delta Ex2) exhibited increased levels of LIMK1, LIMK2, and active phospho-Thr508/505-LIMK1/2, as well as phospho-Ser3-cofilin, compared to wild-type normal MSCs. Similarly, levels of LIMK1 and 2 total protein and active phosphorylated forms were elevated in human vestibular schwannomas compared to normal human Schwann cells (SCs). Reintroduction of wild-type NF2 into Nf2?delta Ex2 MSC reduced LIMK1 and LIMK2 levels. Pharmacological inhibition of LIMK with BMS-5, decreased the viability of Nf2?delta Ex2 MSCs in a dose-dependent manner, but did not affect viability of control MSCs. Similarly, LIMK knockdown decreased viability of Nf2?delta Ex2 MSCs. The decreased viability of Nf2?delta Ex2 MSCs was due to inhibition of cell cycle progression as evidenced by accumulation of cells in G2/M phase. Inhibition of LIMKs arrest cells in early mitosis by decreasing Aurora A activation and cofilin phosphorylation.To increase the search for NF2 therapeutics, we applied an alternative approach to drug discovery with an unbiased pilot high-throughput screen of the Library of Pharmacologically Active Compounds. We assayed for compounds capable of reducing viability of Nf2?delta Ex2 MSC as a cellular model for human NF2 schwannomas. AGK2, a SIRT2 (sirtuin 2) inhibitor, was identified as a candidate compound. SIRT2, a mammalian sirtuin, is a NAD+-dependent protein deacetylase. We show that Nf2?delta Ex2 MSC have higher expression levels of SIRT2 and lower levels of overall lysine acetylation than wild-type control MSC. Pharmacological inhibition of SIRT2 decreases Nf2?delta Ex2 MSC viability in a dose dependent manner without substantially reducing wild-type MSC viability. Inhibition of SIRT2 activity in Nf2?delta Ex2 MSC causes cell death accompanied by release of the necrotic markers lactate dehydrogenase and high mobility group box 1 protein into the medium in the absence of significant apoptosis, autophagy, or cell cycle arrest.Overall this work uncovered two novel potential therapeutic targets, LIMK and SIRT2 for NF2 and tumors associated with merlin deficiency.
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Date Issued: 2013
Identifier: CFE0005398, ucf:50453
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005398

Title: INVESTIGATING THE ROLE OF THE CASPASE-6 CLEAVAGE FRAGMENT OF MUTANT HUNTINGTIN IN HUNTINGTON DISEASE PATHOGENESIS.
Creator: McKinnis, Jourdan A, Southwell, Amber, University of Central Florida
Abstract / Description: Huntington disease (HD) is a devastating and fatal neurodegenerative disease. At the moment, no disease modifying therapies are available, with only symptomatic treatment offered to alleviate psychiatric and some types of motor deficits. As a result, many people will continue to suffer and die from this disease. Small molecule therapies have failed to provide benefit in HD, necessitating more complex gene therapy approaches and the identification of less traditional therapeutic targets. A...
Show moreHuntington disease (HD) is a devastating and fatal neurodegenerative disease. At the moment, no disease modifying therapies are available, with only symptomatic treatment offered to alleviate psychiatric and some types of motor deficits. As a result, many people will continue to suffer and die from this disease. Small molecule therapies have failed to provide benefit in HD, necessitating more complex gene therapy approaches and the identification of less traditional therapeutic targets. A previous study demonstrated that preventing cleavage of the huntingtin (HTT) protein, the protein that when mutated causes HD, by caspase 6 (C6) at amino acid 586 prevents the onset of disease in transgenic HD model mice. This suggests that inhibiting the toxicity initiated by N586 cleavage could be a promising therapeutic strategy, but a safe and specific way to do this in humans has not been identified. General C6 inhibition is not a feasible strategy due to the vital functions it plays throughout life. Thus, the purpose of this study was to investigate whether the C6 cleavage fragment of HTT, N586, is itself a toxic species of HTT or if it initiates a toxic proteolytic pathway in order to identify more viable therapeutic strategies for HD. To accomplish this, we are using novel and highly sensitive immunoprecipitation and flow cytometry (IP-FCM) protein detection assays, specific for the N586 neoepitope of HTT, to evaluate the in vivo persistence of N586 in HD model mice. If N586 is detected, it is likely that it is itself toxic and promoting its degradation may be beneficial. Conversely, if it is not detected, N586 cleavage likely initiates a toxic degradation pathway and promoting its stability may be beneficial. The results of these studies have the potential to define new therapeutic strategies for HD that can be addressed more specifically than generalized C6 inhibition for the prevention of N586-mediated toxicity. The selective targeting of N586 toxicity, either to promote or prevent its degradation depending on our results, would ensure that therapeutic activity is restricted to HTT and reduce the potential for deleterious off-target effects
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Date Issued: 2018
Identifier: CFH2000395, ucf:45801
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000395

Title: INVESTIGATING THE EFFECTS OF SIMULATION ON TRANSFER IN A HIGH RISK CONFRONTATIONAL SETTING.
Creator: Kinsell, Carolyn, Hirumi, Atsusi, University of Central Florida
Abstract / Description: Individuals, who work in high risk confrontational (HRC) settings in which a conflict exists, experience high-stress levels in their jobs and are known to have a high level of decreased performance and decreased survival. Individuals being trained to handle such conflicts should be trained effectively to accomplish the ultimate objective, staying alive. The problem is the lack of research and program evaluations examining effectiveness of training simulations in the transfer of skills under...
Show moreIndividuals, who work in high risk confrontational (HRC) settings in which a conflict exists, experience high-stress levels in their jobs and are known to have a high level of decreased performance and decreased survival. Individuals being trained to handle such conflicts should be trained effectively to accomplish the ultimate objective, staying alive. The problem is the lack of research and program evaluations examining effectiveness of training simulations in the transfer of skills under HRC settings. The purpose of my study was to test if the skill of target acquisition could be effectively transferred to a real environment (RE) after exposure within a virtual environment (VE). Ackerman's (1988) Theory of Ability Determinants of Skill Acquisition supports the progression participants advance through in the transfer of learning. A randomized posttest only comparison group design was used. The population involved 24 novice paintball players. Participants were randomly assigned to a simulation treatment or a non-simulation comparison application. Two days after receiving the intervention, participants engaged in live practice sessions (game 1 and game 2) in a RE where target acquisition skills were measured. Evidence suggests significant differences were found between novice players in the type of intervention received and the number of targets acquired in a RE, whereas, no significant change in scores was found between practice sessions, and no interaction was found between intervention received and practice. Recommendations for replicating studies include: (a) focusing on the manipulation of specific variables within the training context, (b) using different live environments, (c) examining factors that influence teaming and strategy formation, and (d) combining experts and novice players for a closer representation of a population in an HRC setting.
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Date Issued: 2008
Identifier: CFE0002083, ucf:47573
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002083

Title: EXAMINATION OF THE REHABILITATION PROTOCOL OF TRAUMATIC TRANSFEMORAL AMPUTEES AND HOW TO PREVENT BONE MINERAL DENSITY LOSS.
Creator: Jenkinson, Emily R, Fisher, Thomas, University of Central Florida
Abstract / Description: The purpose of this literature review was to identify any adaptations that could be made to the rehabilitation process for Traumatic Transfemoral Amputees. Traumatic Transfemoral Amputation is particularly debilitating with the amputees encountering many obstacles throughout the rehabilitation process. These obstacles can prevent the return to pre-morbid functioning. With an ever-increasing number of amputees within the United States, it is imperative the rehabilitation process be addressed....
Show moreThe purpose of this literature review was to identify any adaptations that could be made to the rehabilitation process for Traumatic Transfemoral Amputees. Traumatic Transfemoral Amputation is particularly debilitating with the amputees encountering many obstacles throughout the rehabilitation process. These obstacles can prevent the return to pre-morbid functioning. With an ever-increasing number of amputees within the United States, it is imperative the rehabilitation process be addressed. This literature review addresses possible adjustments in the initial stages of rehabilitation examining the post-operative, pre-prosthetic, and prosthetic rehabilitation stage to enhance the physical functioning for the amputee. This comprehensive literature review encompassing 63 academic and medical journals analyzes the research literature regarding each of the three stages of the post-operative procedure. The literature review synthesizes the research findings to see how procedures may be adapted to reduce the risk of further co-morbidities such as loss of bone mineral density and disuse atrophy. Loss of bone mineral density and disuse atrophy are the major contributing factors to the amputees decreased mobility. Reducing this loss can be addressed within the initial post-operative, pre-prosthetic, and prosthetic rehabilitation stages. Further research is required to examine the efficacy of these alterations in relation to this specific population.
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Date Issued: 2017
Identifier: CFH2000268, ucf:45964
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000268

Title: DETERMINING THE PRESENCE OF AN IGNITABLE LIQUID RESIDUE IN FIRE DEBRIS SAMPLES UTILIZING TARGET FACTOR ANALYSIS.
Creator: McHugh, Kelly, Sigman, Michael, University of Central Florida
Abstract / Description: Current fire debris analysis procedure involves using the chromatographic patterns of total ion chromatograms, extracted ion chromatograms, and target compound analysis to identify an ignitable liquid according to the American Society for Testing and Materials (ASTM) E 1618 standard method. Classifying the ignitable liquid is accomplished by a visual comparison of chromatographic data obtained from any extracted ignitable liquid residue in the debris to the chromatograms of ignitable liquids...
Show moreCurrent fire debris analysis procedure involves using the chromatographic patterns of total ion chromatograms, extracted ion chromatograms, and target compound analysis to identify an ignitable liquid according to the American Society for Testing and Materials (ASTM) E 1618 standard method. Classifying the ignitable liquid is accomplished by a visual comparison of chromatographic data obtained from any extracted ignitable liquid residue in the debris to the chromatograms of ignitable liquids in a database, i.e. by visual pattern recognition. Pattern recognition proves time consuming and introduces potential for human error. One particularly difficult aspect of fire debris analysis is recognizing an ignitable liquid residue when the intensity of its chromatographic pattern is extremely low or masked by pyrolysis products. In this research, a unique approach to fire debris analysis was applied by utilizing the samplesÃ‚Â' total ion spectrum (TIS) to identify an ignitable liquid, if present. The TIS, created by summing the intensity of each ion across all elution times in a gas chromatography-mass spectrometry (GC-MS) dataset retains sufficient information content for the identification of complex mixtures . Computer assisted spectral comparison was then performed on the samplesÃ‚Â' TIS by target factor analysis (TFA). This approach allowed rapid automated searching against a library of ignitable liquid summed ion spectra. Receiver operating characteristic (ROC) curves measured how well TFA identified ignitable liquids in the database that were of the same ASTM classification as the ignitable liquid in fire debris samples, as depicted in their corresponding area under the ROC curve. This study incorporated statistical analysis to aid in classification of an ignitable liquid, therefore alleviating interpretive error inherent in visual pattern recognition. This method could allow an analyst to declare an ignitable liquid present when utilization of visual pattern recognition alone is not sufficient.
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Date Issued: 2010
Identifier: CFE0003042, ucf:48337
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003042

Title: Content and Effects of Specific Targeted Feedback from Teacher Observations on Student Achievement in a Large Urban School District.
Creator: Haynes, Rachel, Murray, Barbara, Baldwin, Lee, Doherty, Walter, Spadaccini, Becky, University of Central Florida
Abstract / Description: The purpose of this study was to examine the relationships between the content of specific targeted feedback and student achievement and to identify student and teacher knowledge voids from the content of feedback in relationship to achievement level outcomes. This study aimed to deeply analyze the effects of specific targeted feedback as researched by Rafalski (2015). De-identified data from a purposive sample of Rafalski's (2015) original study were selected from a large urban school...
Show moreThe purpose of this study was to examine the relationships between the content of specific targeted feedback and student achievement and to identify student and teacher knowledge voids from the content of feedback in relationship to achievement level outcomes. This study aimed to deeply analyze the effects of specific targeted feedback as researched by Rafalski (2015). De-identified data from a purposive sample of Rafalski's (2015) original study were selected from a large urban school district in Central Florida as well as student achievement level outcome data from the 2013-2014 Florida Comprehensive Assessment Test 2.0 (FCAT 2.0). Raw observation data were used to determine the content of the feedback and analyzed with statistical tests to identify if relationships existed between the feedback content and student achievement. The observation data came from the 2013-2014 Marzano protocol used in the large urban school district in this study. Data were coded from a rubric created to determine the categories and charges of specific targeted feedback. Descriptive statistics were calculated to identify frequencies in the data, and Pearson's r was used to calculate correlations between the categories and charges of feedback coded and the average student achievement level outcomes for FCAT 2.0 assessments for each teacher in the study. Data from frequency calculations showed areas in which elements scored, feedback categories, and feedback charge were heaviest and lacking. Correlations showed areas in which statistically significant relationships occurred and did not occur. From these data it was determined that in terms of supporting level 1 and level 2 students, teachers did not receive much feedback in areas of building student relationships, and probing low expectancy students. Teachers also received predominantly neutral feedback and feedback that contained coaching tips. The validity and relevancy of the feedback was beyond the scope of this study. Correlational data showed both positive and negative relationships between elements coded and student achievement level outcomes as well as feedback categories and student achievement level outcomes. There were no statistically significant relationships between the charge of feedback and student achievement data.
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Date Issued: 2016
Identifier: CFE0006343, ucf:51562
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006343

Title: Geolocation of Diseased Leaves in Strawberry Orchards for a Custom-Designed Octorotor.
Creator: Garcia, Christian, Xu, Yunjun, Lin, Kuo-Chi, Kauffman, Jeffrey, University of Central Florida
Abstract / Description: In recent years, technological advances have shown a strive for more automated processes in agriculture, as seem with the use of unmanned aerial vehicles (UAVs) with onboard sensors in many applications, including disease detection and yield prediction. In this thesis, an octorotor UAV is presented that was designed, built, and flight tested, with features that are custom-designed for strawberry orchard disease detection. To further automate the disease scouting operation, geolocation, or the...
Show moreIn recent years, technological advances have shown a strive for more automated processes in agriculture, as seem with the use of unmanned aerial vehicles (UAVs) with onboard sensors in many applications, including disease detection and yield prediction. In this thesis, an octorotor UAV is presented that was designed, built, and flight tested, with features that are custom-designed for strawberry orchard disease detection. To further automate the disease scouting operation, geolocation, or the process of determining global position coordinates of identified diseased regions based on images taken, is investigated. A Kalman filter is designed, based on a linear measurement model derived from an orthographic projection method, to estimate the target position. Simulation, as well as an ad-hoc experiment using flight data, is performed to compare this filter to the extended Kalman filter (EKF), which is based on the commonly used perspective projection method. The filter is embedded onto a CPU board for real-time use aboard the octorotor UAV, and the algorithm structure for this process is presented. In the later part of the thesis, a probabilistic data association method is used, jointly with a proposed logic-based measurement-to-target correlation method, to analyze measurements of different target sources and is incorporated into the Kalman filter. A simulation and an ad-hoc experiment, using video and flight data acquired aboard the octorotor UAV with a gimballed camera in hover flight, are performed to demonstrate the effectiveness of the algorithm and UAV platform.
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Date Issued: 2016
Identifier: CFE0006305, ucf:51597
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006305

Title: Selective Multivariate Applications in Forensic Science.
Creator: Rinke, Caitlin, Sigman, Michael, Campiglia, Andres, Yestrebsky, Cherie, Kuebler, Stephen, Richardson, Martin, University of Central Florida
Abstract / Description: A 2009 report published by the National Research Council addressed the need for improvements in the field of forensic science. In the report emphasis was placed on the need for more rigorous scientific analysis within many forensic science disciplines and for established limitations and determination of error rates from statistical analysis. This research focused on multivariate statistical techniques for the analysis of spectral data obtained for multiple forensic applications which include...
Show moreA 2009 report published by the National Research Council addressed the need for improvements in the field of forensic science. In the report emphasis was placed on the need for more rigorous scientific analysis within many forensic science disciplines and for established limitations and determination of error rates from statistical analysis. This research focused on multivariate statistical techniques for the analysis of spectral data obtained for multiple forensic applications which include samples from: automobile float glasses and paints, bones, metal transfers, ignitable liquids and fire debris, and organic compounds including explosives. The statistical techniques were used for two types of data analysis: classification and discrimination. Statistical methods including linear discriminant analysis and a novel soft classification method were used to provide classification of forensic samples based on a compiled library. The novel soft classification method combined three statistical steps: Principal Component Analysis (PCA), Target Factor Analysis (TFA), and Bayesian Decision Theory (BDT) to provide classification based on posterior probabilities of class membership. The posterior probabilities provide a statistical probability of classification which can aid a forensic analyst in reaching a conclusion. The second analytical approach applied nonparametric methods to provide the means for discrimination between samples. Nonparametric methods are performed as hypothesis test and do not assume normal distribution of the analytical figures of merit. The nonparametric permutation test was applied to forensic applications to determine the similarity between two samples and provide discrimination rates. Both the classification method and discrimination method were applied to data acquired from multiple instrumental methods. The instrumental methods included: Laser Induced-Breakdown Spectroscopy (LIBS), Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, and Gas Chromatography-Mass Spectrometry (GC-MS). Some of these instrumental methods are currently applied to forensic applications, such as GC-MS for the analysis of ignitable liquid and fire debris samples; while others provide new instrumental methods to areas within forensic science which currently lack instrumental analysis techniques, such as LIBS for the analysis of metal transfers. The combination of the instrumental techniques and multivariate statistical techniques is investigated in new approaches to forensic applications in this research to assist in improving the field of forensic science.
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Date Issued: 2012
Identifier: CFE0004628, ucf:49942
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004628

Target Factor Analysis (2)	+ -
target (2)	+ -
target detection (2)	+ -
Automatic Target Recognition (1)	+ -
BCN etching (1)	+ -

Bat (1)	+ -
Bone Mineral Density (1)	+ -
Boron carbon nitride (BCN) (1)	+ -
C2000 (1)	+ -
CATD (1)	+ -
CB (1)	+ -
CT20p (1)	+ -
Chemometrics (1)	+ -
Constant absolute target direction (1)	+ -
Correlation Pattern Recognition (1)	+ -
DNA Motifs (1)	+ -
Data Association (1)	+ -
Disease Detection (1)	+ -
EUV (1)	+ -
Embedded Target (1)	+ -
Explosive Detection (1)	+ -
FTIR (1)	+ -
Fab chaperone assisted RNA crystallography (1)	+ -
Fire Debris Analysis (1)	+ -
Gene Regulation (1)	+ -
Geolocation (1)	+ -
HeLa tumor (1)	+ -
Huntington's Disease (1)	+ -
IPOP (1)	+ -
IPV (1)	+ -

ETD Collection (25)	+ -
Honors Collection (5)	+ -

University of Central Florida (30)	+ -
Khaled, Annette (3)	+ -
Richardson, Martin (3)	+ -
Altomare, Deborah (2)	+ -
Baldwin, Lee (2)	+ -

Boutton, Andrew (2)	+ -
Campiglia, Andres (2)	+ -
Fernandez-Valle, Cristina (2)	+ -
Harper, James (2)	+ -
Jin, Yier (2)	+ -
Sigman, Michael (2)	+ -
Yestrebsky, Cherie (2)	+ -
Anderson, Kathryn (1)	+ -
Atia, George (1)	+ -
Bagci, Ulas (1)	+ -
Belfield, Kevin D. (1)	+ -
Brown, Christopher (1)	+ -
Buckridge, Hilary (1)	+ -
Carr, Ana (1)	+ -
Chow, Louis (1)	+ -
Chunyu, Jiangmin (1)	+ -
Cooney, Lucretia (1)	+ -
D'Angelo, John (1)	+ -
Ding, Jun (1)	+ -
Doherty, Walter (1)	+ -
Dolan, Thomas (1)	+ -
Downs, Joshua (1)	+ -
Fisher, Thomas (1)	+ -
Flores-Fernandez, Orielyz (1)	+ -
Foroosh, Hassan (1)	+ -

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