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Title: The Profession of Modeling and Simulations: Unifying the Organization.
Creator: Lord, John, Caulkins, Bruce, Truman, Barbara, Maraj, Crystal, Bockelman, Patricia, University of Central Florida
Abstract / Description: The organization of Modeling and Simulation (M(&)S) as a profession started in the early twenty-first century spurred by the advent of computers and the vast networking capabilities of contemporary computing. M(&)S is still in its infancy when compared to other disciplines, such as engineering, computer science and mathematics. However, the profession has experienced significant growth in part due to the varied use of M(&)S techniques and tools within almost every discipline.Professional...
Show moreThe organization of Modeling and Simulation (M(&)S) as a profession started in the early twenty-first century spurred by the advent of computers and the vast networking capabilities of contemporary computing. M(&)S is still in its infancy when compared to other disciplines, such as engineering, computer science and mathematics. However, the profession has experienced significant growth in part due to the varied use of M(&)S techniques and tools within almost every discipline.Professional organizations and academic programs supporting M(&)S across the country have started to materialize. In a short timeframe, the growth of these supporting organizations has outpaced their ability to stay unified as a discipline, aligned with standardized Knowledge, Skills, and Abilities (KSAs) and with growing stakeholder needs.Consequently, there appear to be gaps in the M(&)S professional organization. Such as a lack of synchronization between the three primary stakeholder groups of the M(&)S profession: academia, government, and industry. The discipline's professional organization fails to recognize a single body of knowledge as an authoritative reference for M(&)S KSAs. Academic institutions do not have unanimity regarding targeted KSAs. Industry lacks the confidence to hire M(&)S professionals who have a core understanding of KSAs directly associated with the version of M(&)S used by each separate industry.This research study attempts to take a coordinated step forward in unifying the M(&)S discipline by assessing and prioritizing the current competencies and standards required of M(&)S professionals and identifying the needs and competencies valued by primary stakeholders. A survey instrument was developed in conjunction with Rebecca Leis' doctorate research. The instrument was distributed to M(&)S stakeholders to ascertain the breadth of the needed, valued, and required KSAs within the domain. The survey was evaluated by cross-referencing questions and tabulating responses. Results from this research suggest ways in which stakeholders can coordinate efforts in advancing the M(&)S professional organization and support a uniformed set of KSAs needed in academia, government, and industry now and in the future.
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Date Issued: 2019
Identifier: CFE0007489, ucf:52876
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007489

Title: Understanding How, Where and How much Freight Flows Using 2012 Commodity Flow Survey Data.
Creator: Keya, Nowreen, Eluru, Naveen, Abdel-Aty, Mohamed, Anowar, Sabreena, Uddin, Nizam, University of Central Florida
Abstract / Description: In recent years, with increased economic globalization, growing e-commerce and internet based shopping, freight movement patterns are undergoing a transformative change. The shipment size distribution is moving towards a higher share of smaller size shipments affecting transportation mode and vehicle type requirements. In addition, freight transportation mode is closely affected by the destination location (and its attributes). In our dissertation, we contribute to freight research by...
Show moreIn recent years, with increased economic globalization, growing e-commerce and internet based shopping, freight movement patterns are undergoing a transformative change. The shipment size distribution is moving towards a higher share of smaller size shipments affecting transportation mode and vehicle type requirements. In addition, freight transportation mode is closely affected by the destination location (and its attributes). In our dissertation, we contribute to freight research by developing a comprehensive framework to examine the how, where and how much freight flows in US. Specifically, we study the following dimensions of freight flow: (1) transportation mode, (2) mode and shipment weight choice and (3) mode and destination choice. For analyzing mode choice, an advanced discrete freight mode choice model- a hybrid utility-regret based model system has been estimated while accommodating for shipper level unobserved heterogeneity. To demonstrate the applicability of the proposed model system, detailed policy analyses examining the implementation of vehicle fleet automation and rerouting of freight movements away from a region were considered. While shipment weight could be considered as an explanatory variable in modeling mode choice (or vice-versa), it is more likely that the decision of mode and shipment choice is a simultaneous process. This joint decision is investigated both simultaneously employing a closed form copula structure and sequentially employing latent segmentation based sequence model. For destination choice, we investigated the connection between shipping mode and destination choice of shipment in a latent segmentation based sequential form. The analysis for the dissertation is conducted using 2012 Commodity Flow Survey (CFS) data.
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Date Issued: 2018
Identifier: CFE0007574, ucf:52569
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007574

Title: Characterization of a Spiking Neuron Model via a Linear Approach.
Creator: Jabalameli, Amirhossein, Behal, Aman, Hickman, James, Haralambous, Michael, University of Central Florida
Abstract / Description: In the past decade, characterizing spiking neuron models has been extensively researched as anessential issue in computational neuroscience. In this thesis, we examine the estimation problemof two different neuron models. In Chapter 2, We propose a modified Izhikevich model withan adaptive threshold. In our two-stage estimation approach, a linear least squares method anda linear model of the threshold are derived to predict the location of neuronal spikes. However,desired results are not...
Show moreIn the past decade, characterizing spiking neuron models has been extensively researched as anessential issue in computational neuroscience. In this thesis, we examine the estimation problemof two different neuron models. In Chapter 2, We propose a modified Izhikevich model withan adaptive threshold. In our two-stage estimation approach, a linear least squares method anda linear model of the threshold are derived to predict the location of neuronal spikes. However,desired results are not obtained and the predicted model is unsuccessful in duplicating the spikelocations. Chapter 3 is focused on the parameter estimation problem of a multi-timescale adaptivethreshold (MAT) neuronal model. Using the dynamics of a non-resetting leaky integrator equippedwith an adaptive threshold, a constrained iterative linear least squares method is implemented tofit the model to the reference data. Through manipulation of the system dynamics, the thresholdvoltage can be obtained as a realizable model that is linear in the unknown parameters. This linearlyparametrized realizable model is then utilized inside a prediction error based framework to identifythe threshold parameters with the purpose of predicting single neuron precise firing times. Thisestimation scheme is evaluated using both synthetic data obtained from an exact model as well asthe experimental data obtained from in vitro rat somatosensory cortical neurons. Results show theability of this approach to fit the MAT model to different types of reference data.
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Date Issued: 2015
Identifier: CFE0005958, ucf:50803
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005958

Title: A COUPLED CFD-LUMPED PARAMETER MODEL OF THE HUMAN CIRCULATION: ELUCIDATING THE HEMODYNAMICS OF THE HYBRID NORWOOD PALLIATIVE TREATMENT AND EFFECTS OF THE REVERSE BLALOCK-TAUSSIG SHUNT PLACEMENT AND DIAMETER.
Creator: Ceballos, Andres, Kassab, Alain, Bai, Yuanli, Deng, Weiwei, DeCampli, William, Divo, Eduardo, University of Central Florida
Abstract / Description: The Hybrid Norwood (HN) is a relatively new first stage procedure for neonates with Hypoplastic Left Heart Syndrome (HLHS), in which a sustainable univentricular circulation is established in a less invasive manner than with the standard procedure. A computational multiscale model of such HLHS circulation following the HN procedure was used to obtain detailed hemodynamics. Implementation of a reverse-BT shunt (RBTS), a synthetic bypass from the main pulmonary to the innominate artery placed...
Show moreThe Hybrid Norwood (HN) is a relatively new first stage procedure for neonates with Hypoplastic Left Heart Syndrome (HLHS), in which a sustainable univentricular circulation is established in a less invasive manner than with the standard procedure. A computational multiscale model of such HLHS circulation following the HN procedure was used to obtain detailed hemodynamics. Implementation of a reverse-BT shunt (RBTS), a synthetic bypass from the main pulmonary to the innominate artery placed to counteract aortic arch stenosis, and its effects on local and global hemodynamics were studied.A synthetic and a 3D reconstructed, patient derived anatomy after the HN procedure were utilized, with varying degrees of distal arch obstruction, or stenosis, (nominal and 90% reduction in lumen) and varying RBTS diameters (3.0, 3.5, 4.0 mm). A closed lumped parameter model (LPM) for the peripheral or distal circulation coupled to a 3D Computational Fluid Dynamics (CFD) model that allows detailed description of the local hemodynamics was created for each anatomy. The implementation of the RBTS in any of the chosen diameters under severe stenosis resulted in a restoration of arterial perfusion to near-nominal levels. Shunt flow velocity, vorticity, and overall wall shear stress levels are inverse functions of shunt diameter, while shunt perfusion and systemic oxygen delivery correlates positively with diameter. No correlation of shunt diameter with helicity was recorded.In the setting of the hybrid Norwood circulation, our results suggest: (1) the 4.0mm RBTS may be more thrombogenic when implemented in the absence of severe arch stenosis and (2) the 3.0mm and 3.5mm RBTS may be a more suitable alternative, with preference to the latter since it provides similar hemodynamics at lower levels of wall shear stress.
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Date Issued: 2015
Identifier: CFE0005772, ucf:50068
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005772

Title: COMMUNICATION MODALITY AND AFTER ACTION REVIEW PERFORMANCE IN A DISTRIBUTED IMMERSIVE VIRTUAL ENVIRONMENT.
Creator: Kring, Jason P., Salas, Eduardo, University of Central Florida
Abstract / Description: Virtual teams, in which geographically separate individuals interact via a technology bridge to perform collective activities, are becoming commonplace in the military, business, and education. Despite numerous benefits, virtual teams often lack face-to-face (FTF) interaction which may alter communication processes and subsequently affect team factors necessary for successful performance. Previous research indicated local teams, with members at the same physical location, outperformed...
Show moreVirtual teams, in which geographically separate individuals interact via a technology bridge to perform collective activities, are becoming commonplace in the military, business, and education. Despite numerous benefits, virtual teams often lack face-to-face (FTF) interaction which may alter communication processes and subsequently affect team factors necessary for successful performance. Previous research indicated local teams, with members at the same physical location, outperformed distributed teams, with members at different locations, in a series of military-style missions in an immersive virtual environment (VE). The present study replicated and extended this effort by measuring how communication modality affects three team factors often cited as facilitating performance: shared mental models (SMMs), cohesion (task and interpersonal), and trust (cognitive and emotional). Local teams were expected to again perform better than distributed teams and exhibit greater SMM similarity, cohesion, and trust. Furthermore, a brief team communication training (TCT) program was administered to half of the teams on the premise training would improve distributed team performance. Thirty two, 2-person teams were distributed into four experimental conditions (n = 8) based on location (local vs. distributed) and training (TCT vs. no-TCT) and then conducted five VE missions. Each mission required the team to search a 10-room building for hazardous materials and opposing forces while protecting neutral bystanders. Results showed local teams again performed better than distributed teams on overall mission performance, however the difference was less robust than anticipated. Analyses of the three team factors revealed a main effect of location as local teams reported higher levels of cognitive trust and more agreement on one of 10 SMM measures than distributed teams. A similar difference was found for the main effect of TCT with trained teams exhibiting higher cognitive trust than no-TCT teams. Results support that distributed teams operating in a common virtual setting experience performance deficits when compared to their physically co-located counterparts. Future research is needed to address the role of cognitive trust for virtual teams, the time required to develop detectable levels of emotional trust and cohesion, and how social presence between team members influences performance.
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Date Issued: 2004
Identifier: CFE0000054, ucf:46074
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000054

Title: MODELING THE INFLUENCES OF PERSONALITY PREFERENCES ON THE SELECTION OF INSTRUCTIONAL STRATEGIES ININTELLIGENT TUTORING SYSTEMS.
Creator: Sottilare, Robert, Proctor, Michael, University of Central Florida
Abstract / Description: This thesis hypothesizes that a method for selecting instructional strategies (specifically media) based in part on a relationship between learning style preference and personality preference provides more relevant and understandable feedback to students and thereby higher learning effectiveness. This research investigates whether personality preferences are valid predictors of learning style preferences. Since learning style preferences are a key consideration in instructional strategies and...
Show moreThis thesis hypothesizes that a method for selecting instructional strategies (specifically media) based in part on a relationship between learning style preference and personality preference provides more relevant and understandable feedback to students and thereby higher learning effectiveness. This research investigates whether personality preferences are valid predictors of learning style preferences. Since learning style preferences are a key consideration in instructional strategies and instructional strategies are a key consideration in learning effectiveness, this thesis contributes to a greater understanding of the relationship between personality preferences and effective learning in intelligent tutoring systems (ITS). This research attempts to contribute to the goal of a "truly adaptive ITS" by first examining relationships between personality preferences and learning style preferences; and then by modeling the influences of personality on learning strategies to optimize feedback for each student. This thesis explores the general question "what can personality preferences contribute to learning in intelligent tutoring systems?" So, why is it important to evaluate the relationship between personality preferences and learning strategies in ITS? "While one-on-one human tutoring is still superior to ITS in general, this approach is idiosyncratic and not feasible to deliver to [any large population] in any cost-effective manner." (Loftin, 2004). Given the need for ITS in large, distributed populations (i.e. the United States Army), it is important to explore methods of increasing ITS performance and adaptability. Findings of this research include that the null hypothesis that "there is no dependency between personality preference variables and learning style preference variables" was partly rejected. Highly significant correlations between the personality preferences, openness and extraversion, were established for both the active-reflective and sensing-intuitive learning style preferences. Discussion of other relationships is provided.
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Date Issued: 2006
Identifier: CFE0001403, ucf:47074
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001403

Title: THE ADJUDICATION OF PRESIDENTIAL POWER IN THE U.S. SUPREME COURT:A PREDICTIVE MODEL OF INDIVIDUAL JUSTICE VOTING.
Creator: Curry, Todd, Lanier, Drew, University of Central Florida
Abstract / Description: The interaction between the President and Congress is many times quite public and well documented (Cronin 1980; Covington et al. 1995; Fisher 1994; Schlesinger 2004). Similarly, relations between the Congress and the Supreme Court are well documented; Congress makes law and, if requested, the Court interprets it. The interaction between the president and the Court, however, is not nearly as well defined, and certainly not as public. Supreme Court cases involving the president directly are...
Show moreThe interaction between the President and Congress is many times quite public and well documented (Cronin 1980; Covington et al. 1995; Fisher 1994; Schlesinger 2004). Similarly, relations between the Congress and the Supreme Court are well documented; Congress makes law and, if requested, the Court interprets it. The interaction between the president and the Court, however, is not nearly as well defined, and certainly not as public. Supreme Court cases involving the president directly are fairly rare. King and Meernik (1995) identify 347 cases involving the foreign policy powers of the president, decided from 1790 to 1996, which is roughly 1.5 cases per calendar year. This study will examine the influence of attitudinal and extra-attitudinal factors on the individual level decision-making of the U.S. Supreme Court justices in cases involving presidential power. By using both attitudinal and extra-attitudinal factors, such as public opinion and armed conflict, this study will explore the limitations of a simple attitudinal model in complex and highly salient cases such as those that involve presidential power. The cases to be examined will be all presidential power cases decided from 1949 to 2005 (N = 38). The unit of analysis will, however, be the justice's individual-level vote (N = 337).
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Date Issued: 2006
Identifier: CFE0001202, ucf:46953
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001202

Title: VERIFICATION OF FAA'S EMISSIONS AND DISPERSION MODELING SYSTEM (EDMS).
Creator: Martin, Anjoli, Wayson, Roger, University of Central Florida
Abstract / Description: Air quality has been a major environmental concern for many years. Recently the issue of airport emissions has presented growing concerns and is being studied in much more depth. Airport emissions come from a variety of point, line and area sources, making emissions modeling for airports very complex and more involved. Accurate air quality models, specific to airport needs, are required to properly analyze this complex array of air pollution sources created by airports. Accurate air quality...
Show moreAir quality has been a major environmental concern for many years. Recently the issue of airport emissions has presented growing concerns and is being studied in much more depth. Airport emissions come from a variety of point, line and area sources, making emissions modeling for airports very complex and more involved. Accurate air quality models, specific to airport needs, are required to properly analyze this complex array of air pollution sources created by airports. Accurate air quality models are needed to plan for increased growth of current airports and address concerns over proposed new ones. The Federal Aviation Administration's (FAA) Emissions and Dispersion Modeling System (EDMS) is a program that is the required model for assessing emissions from airport sources. This research used EDMS Version 4.21, which incorporates the EPA dispersion model AERMOD, to model detailed airport data and compare the model's predicted values to the actual measured carbon monoxide concentrations at 25 locations at a major U.S. airport. Statistics relating the model characteristics as well as trends are presented. In this way, a thorough investigation of the accuracy of the EDMS modeled values of carbon monoxide was possible. EDMS modeling included two scenarios, the first scenario referred to as practice detail included general airport information that a modeler could find from the airport being studied and the second scenario referred to as research detail utilized very detailed information from observer logs during a three day observation period. Each of the modeling scenarios was compared to the field measured data and to each other. These comparisons are important to insure the model is adequately describing emissions sources at airports. Data analysis of this study was disappointing since measured levels of CO were generally higher than modeled values. Since EDMS is continually changing and improving perhaps these results can help enhance future models.
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Date Issued: 2006
Identifier: CFE0001282, ucf:46903
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001282

Title: IMPLEMENTING LEXICAL AND CREATIVE INTENTIONALITY IN SYNTHETIC PERSONALITY.
Creator: Vick, Erik, Cannon-Bowers, Jan, University of Central Florida
Abstract / Description: Creating engaging, interactive, and immersive synthetic characters is a difficult task and evaluating the success of a synthetic character is often even more difficult. The later problem is solved by extending Turing's Imitation Game thusly: computational construct should be evaluated based on the criteria of how well the character can mimic a human. In order to accomplish a successful evaluation of the proposed metric, synthetic characters must be consistently believable and capable of role...
Show moreCreating engaging, interactive, and immersive synthetic characters is a difficult task and evaluating the success of a synthetic character is often even more difficult. The later problem is solved by extending Turing's Imitation Game thusly: computational construct should be evaluated based on the criteria of how well the character can mimic a human. In order to accomplish a successful evaluation of the proposed metric, synthetic characters must be consistently believable and capable of role-appropriate emotional expression. The author believes traditional synthetic characters must be improved to meet this goal. For a synthetic character to be believable, human users must be able to perceive a link between the mental state of the character and its behaviors. That is to say, synthetic characters must possess intentionality. In addition to intentionality, the mental state of the character must be human-like in order to provide an adequate frame of reference for the human users' internal simulations, to wit, the character's mental state must be comprised of a synthetic model of personality, of personality dynamics, and of cognition, each of which must be psychologically valid and of sufficient fidelity for the type of character represented. The author proposes that synthetic characters possessing these three models are more accurately described as synthetic personalities. The author proposes and implements computational models of personality, personality dynamics, and cognition in order to evaluate the psychological veracity of these models and computational equivalence between the models and the implementation as a first step in the process of creating believable synthetic personalities.
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Date Issued: 2005
Identifier: CFE0000422, ucf:46397
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000422

Title: A THEORETICAL APPROACH TO ASSESSING ANNUAL ENERGY BALANCE IN GRAY WHALES (ESCHRICHTIUS ROBUSTUS).
Creator: Greenwald, Nathalie, Worthy, Graham, University of Central Florida
Abstract / Description: While direct measurements of energetic demands are nearly impossible to collect on large cetaceans, comprehensive bioenergetic models can give insights on such parameters by combining physiological and ecological knowledge. This model was developed to estimate necessary food intake of gray whales, Eschrichtius robustus, of the Eastern North Pacific stock. Field Metabolic Rates (FMR) for gray whales were first estimated based on various assumptions (e.g. volumetric representation of gray...
Show moreWhile direct measurements of energetic demands are nearly impossible to collect on large cetaceans, comprehensive bioenergetic models can give insights on such parameters by combining physiological and ecological knowledge. This model was developed to estimate necessary food intake of gray whales, Eschrichtius robustus, of the Eastern North Pacific stock. Field Metabolic Rates (FMR) for gray whales were first estimated based on various assumptions (e.g. volumetric representation of gray whales, extent of their feeding season, and blubber depth distribution) using morphometric data, energetic costs, and food assimilation according to age and gender specific requirements. Food intake rates for gray whales of varying maturity and gender were then estimated based on FMR and caloric value of prey and compared to food intake rates of previous studies. Monte Carlo simulations and sensitivity analysis were performed to assess the model's predictions compared to observed field data from previous studies. Predicted average food intakes for adult male, pregnant/ lactating female, and immature whales were 475 ± 300, 525 ± 300 and 600 ± 300 kg d-1. Estimated blubber depths resulting from these food intakes were comparable to field data obtained from whaling data. Sensitivity analysis indicated food intake, from all parameters, as having the highest impact on the percent change in ending mass from a simulation. These food intake estimates are similar to those found in a previous study and fall within the range of food intake per body mass observed in other species of cetaceans. Though thermoregulation can be a factor in some cetaceans, it appears not to be an additional cost for gray whales as the present model's predicted lower critical temperatures for the whales (TLC) were below ambient temperatures. With temperatures increasing in the Bering Sea, the main prey of gray whales, ampeliscid amphipods, could be adversely affected, possibly resulting in increased food shortages leading to a surge in gray whale strandings.
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Date Issued: 2005
Identifier: CFE0000443, ucf:46375
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000443

Title: EVALUATION OF A MICROWAVE RADIATIVE TRANSFER MODEL FOR CALCULATING SATELLITE BRIGHTNESS TEMPERATURE.
Creator: Thompson, Simonetta, Jones, Linwood, University of Central Florida
Abstract / Description: Remote sensing is the process of gathering and analyzing information about the earth's ocean, land and atmosphere using electromagnetic "wireless" techniques. Mathematical models, known as Radiative Transfer Models (RTM), are developed to calculate the observed radiance (brightness temperature) seen by the remote sensor. The RTM calculated brightness temperature is a function of fourteen environmental parameters, including atmospheric profiles of temperature, pressure and moisture, sea...
Show moreRemote sensing is the process of gathering and analyzing information about the earth's ocean, land and atmosphere using electromagnetic "wireless" techniques. Mathematical models, known as Radiative Transfer Models (RTM), are developed to calculate the observed radiance (brightness temperature) seen by the remote sensor. The RTM calculated brightness temperature is a function of fourteen environmental parameters, including atmospheric profiles of temperature, pressure and moisture, sea surface temperature, and cloud liquid water. Input parameters to the RTM model include data from NOAA Centers for Environmental Prediction (NCEP), Reynolds weekly Sea Surface Temperature and National Ocean Data Center (NODC) WOA98 Ocean Salinity and special sensor microwave/imager (SSM/I) cloud liquid water. The calculated brightness temperatures are compared to collocated measurements from the WindSat satellite. The objective of this thesis is to fine tune the RadTb model, using simultaneous environmental parameters and measured brightness temperature from the well-calibrated WindSat radiometer. The model will be evaluated at four microwave frequencies (6.8 GHz, 10.7 GHz, 18.7 GHz, and 37.0 GHz) looking off- nadir for global radiance measurement.
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Date Issued: 2004
Identifier: CFE0000325, ucf:46303
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000325

Title: IMPROVING METACOMPREHENSION AND LEARNING THROUGH GRADUATED CONCEPT MODEL DEVELOPMENT.
Creator: Kring, Eleni, Salas, Eduardo, University of Central Florida
Abstract / Description: Mental model development, deeper levels of information processing, and elaboration are critical to learning. More so, individuals' metacomprehension accuracy is integral to making improvements to their knowledge base. In other words, without an accurate perception of their knowledge on a topic, learners may not know that knowledge gaps or misperceptions exist and, thus, would be less likely to correct them. Therefore, this study offered a dual-process approach that aimed at enhancing...
Show moreMental model development, deeper levels of information processing, and elaboration are critical to learning. More so, individuals' metacomprehension accuracy is integral to making improvements to their knowledge base. In other words, without an accurate perception of their knowledge on a topic, learners may not know that knowledge gaps or misperceptions exist and, thus, would be less likely to correct them. Therefore, this study offered a dual-process approach that aimed at enhancing metacomprehension. One path aimed at advancing knowledge structure development and, thus, mental model development. The other focused on promoting a deeper level of information processing through processes like elaboration. It was predicted that this iterative approach would culminate in improved metacomprehension and increased learning. Accordingly, using the Graduated Concept Model Development (GCMD) approach, the role of learner-generated concept model development in facilitating metacomprehension and knowledge acquisition was examined. Concept maps have had many roles in the learning process as mental model assessment tools and advanced organizers. However, this study examined the process of concept model building as an effective training tool. Whereas, concept maps functioning as advanced organizers are certainly beneficial, it would seem that the benefits of having a learner examine and amend the current state of their knowledge through concept model development would prove more effective for learning. In other words, learners looking at an advanced organizer of the training material may feel assured that they have a thorough understanding of it. Only when they are forced to create a representation of the material would the gaps and misperceptions in their knowledge base likely be revealed. In short, advanced organizers seem to rely on recognition, where concept model development likely requires recalling and understanding 'how' and 'why' the interrelationships between concepts exist. Therefore, the Graduated Concept Model Development (GCMD) technique offered in this study was based on the theory that knowledge acquisition improves when learners integrate new information into existing knowledge, assign elaborated meanings to concepts, correct misperceptions, close knowledge gaps, and strengthen accurate connections between concepts by posing targeted questions against their existing knowledge structures. This study placed an emphasis on meaningful learning and suggested a process by which newly introduced concepts would be manipulated for the purpose of improving metacomprehension by strengthening accurate knowledge structures and mental model development, and through deeper and elaborated information processing. Indeed, central to improving knowledge deficiencies and misunderstandings is metacomprehension, and the constructing of concepts maps was hypothesized to improve metacomprehension accuracy and, thus, learning. This study was a one-factor between-groups design with concept map type as the independent variable, manipulated at four levels: no concept map, concept map as advanced organizer, learner-built concept map with feedback, and learner-built concept map without feedback. The dependent variables included performance (percent correct) on a declarative and integrative knowledge assessment, mental model development, and metacomprehension accuracy. Participants were 68 (34 female, 34 male, ages 18-35, mean age = 21.43) undergraduate students from a major southeastern university. Participants were randomly assigned to one of the four experimental conditions, and analysis revealed no significant differences between the groups. Upon arrival, participants were randomly assigned to one of the four experimental conditions. Participants then progressed through the three stages of the experiment. In Stage I, participants completed forms regarding informed consent, general biographical information, and task self-efficacy. In Stage II, participants completed the self-paced tutorial based on the Distributed Dynamic Decision Making (DDD) model, a simulated military command and control environment aimed at creating events to encourage team coordination and performance (for a detailed description, see Kleinman & Serfaty, 1989). The manner by which participants worked through the tutorial was determined by their assigned concept map condition. Upon finishing each module of the tutorial, participants then completed a metacomprehension prediction question. In Stage III, participants completed the computer-based knowledge assessment test, covering both declarative and integrative knowledge, followed by the metacomprehension postdiction question. Participants then completed the card sort task, as the assessment of mental model development. Finally, participants completed a general study survey and were debriefed as to the purpose of the study. The entire experiment lasted approximately 2 to 3 hours. Results indicated that the GCMD condition showed a stronger indication of metacomprehension accuracy, via prediction measures, compared with the other three conditions (control, advanced organizer, and feedback), and, specifically, significantly higher correlations than the other three conditions in declarative knowledge. Self-efficacy measures also indicated that the higher metacomprehension accuracy correlation observed in the GCMD condition was likely the result of the intervention, and not due to differences in self-efficacy in that group of participants. Likewise, the feedback and GCMD conditions led to significantly high correlations for metacomprehension accuracy based on levels of understanding on the declarative knowledge tutorial module (Module 1). The feedback condition also showed similar responses for the integrative knowledge module (Module 2). The advanced organizer, feedback, and GCMD conditions were also found to have significantly high correlation of self-reported postdiction of performance on the knowledge assessment and the actual results of the knowledge assessment results. However, results also indicated that there were no significant findings between the four conditions in mental model assessment and knowledge assessment. Nevertheless, results support the relevance of accurate mental model development in knowledge assessment outcomes. Retrospectively, two opposing factors may have complicated efforts to detect additional differences between groups. From one side, the experimental measures may not have been rigorous enough to filter out the effect from the intervention itself. Conversely, software usability issues and the resulting limitations in experimental design may have worked negatively against the two concept mapping conditions and, inadvertently, suppressed effects of the intervention. Future research in the GCMD approach will likely review cognitive workload, concept mapping software design, and the sensitivity of the measures involved.
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Date Issued: 2004
Identifier: CFE0000312, ucf:46311
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000312

Title: DESIGN OF AN ADAPTIVE AUTOPILOT FOR AN EXPENDABLE LAUNCH VEHICLE.
Creator: Plaisted, Clinton, Leonessa, Alexander, University of Central Florida
Abstract / Description: This study investigates the use of a Model Reference Adaptive Control (MRAC) direct approach to solve the attitude control problem of an Expendable Launch Vehicle (ELV) during its boost phase of flight. The adaptive autopilot design is based on Lyapunov Stability Theory and provides a useful means for controlling the ELV in the presence of environmental and dynamical uncertainties. Several different basis functions are employed to approximate the nonlinear parametric uncertainties in the...
Show moreThis study investigates the use of a Model Reference Adaptive Control (MRAC) direct approach to solve the attitude control problem of an Expendable Launch Vehicle (ELV) during its boost phase of flight. The adaptive autopilot design is based on Lyapunov Stability Theory and provides a useful means for controlling the ELV in the presence of environmental and dynamical uncertainties. Several different basis functions are employed to approximate the nonlinear parametric uncertainties in the system dynamics. The control system is designed so that the desire dresponse to a reference model would be tracked by the closed-loop system. The reference model is obtained via the feedback linearization technique applied to the nonlinear ELV dynamics. The adaptive control method is then applied to a representative ELV longitudinal motion, specifically the 6th flight of Atlas-Centaur launch vehicle (AC-6) in 1965. The simulation results presented are compared to that of the actual AC-6 post-flight trajectory reconstruction. Recommendations are made for modification and future applications of the method for several other ELV dynamics issues, such as control saturation, engine inertia, flexible body dynamics, and sloshing of liquid fuels.
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Date Issued: 2008
Identifier: CFE0002006, ucf:47616
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002006

Title: PERSPECTIVES OF HEALTH INFORMATION MANAGEMENT FACULTY USE OF AN E-LEARNING LABORATORY AND TECHNOLOGY ACCEPTANCE.
Creator: Meli, Peggy, Sivo, Stephen, University of Central Florida
Abstract / Description: "As the delivery of healthcare has become more sophisticated, scientific, and complex, the need for HIM (Health Information Management) professionals at all levels has increased, and the role and status of those managing these functions has increased accordingly." (AHIMA, September 24, 2007). Studies by the Institute of Medicine and others have found suboptimal technology use throughout the healthcare industry. The American Health Information Management Association (AHIMA) developed the e-HIM...
Show more"As the delivery of healthcare has become more sophisticated, scientific, and complex, the need for HIM (Health Information Management) professionals at all levels has increased, and the role and status of those managing these functions has increased accordingly." (AHIMA, September 24, 2007). Studies by the Institute of Medicine and others have found suboptimal technology use throughout the healthcare industry. The American Health Information Management Association (AHIMA) developed the e-HIM Virtual Lab (V-lab) to train students in the use of new technology applications in response to IOM findings. Faculty are the gatekeepers for use of instructional technology in educational settings. Many disciplines have evaluated instructional technology use by students. There are very few studies on faculty use of instructional technology. There are no published studies of the determinant factors influencing health information management (HIM) faculty use of instructional technology. Therefore, the purpose of this study is to evaluate the faculty's attitude and behavior toward the use of the V-lab instructional technology. A non-random one group pretest posttest design was used to test the hypothetical Instructional Perception -Technology Acceptance Model (IP- TAM) for faculty perceptions regarding system functionality, usability and technology acceptance. The Path Analysis determined the strongest construct indicators for intent to use the V-lab were Perceived Usefulness (PU), Perceived Ease Of Use (PEOU), System Functionality and Usability (SFU). These findings support the recommendation for a collaborative examination of the existing V-lab systems to improve utilization and success.
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Date Issued: 2008
Identifier: CFE0002140, ucf:47500
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002140

Title: DEVELOPMEMNT OF A MODELING AND SIMULATION TRAINING NEEDS MODEL FOR SELECTED DEFENSE ACQUISITION WORKFORCE COMMUNITIES.
Creator: PEH, LIK CHUN, PROCTOR, MICHAEL, University of Central Florida
Abstract / Description: The DoD Modeling and Simulation Steering Committee (M&S SC) identified Modeling and Simulation (M&S) as an educational objective for the Acquisition, Technology and Logistics (AT&L) workforce. Notably, past usages of M&S in system acquisitions for both DoD and commercial industry have demonstrated improvements in efficiency and effectiveness over traditional acquisition techniques. However, to achieve expected and consistent performance by this workforce in these new techniques, the M&S...
Show moreThe DoD Modeling and Simulation Steering Committee (M&S SC) identified Modeling and Simulation (M&S) as an educational objective for the Acquisition, Technology and Logistics (AT&L) workforce. Notably, past usages of M&S in system acquisitions for both DoD and commercial industry have demonstrated improvements in efficiency and effectiveness over traditional acquisition techniques. However, to achieve expected and consistent performance by this workforce in these new techniques, the M&S essential skill requirements for this workforce may be extensive. This research aims to validate the content and level of competency in selected M&S tools and technology necessary for consistent workforce performance. The notion here is to achieve greater efficiency and effectiveness in the acquisition process through thresholds of competency that must be resident in or available to the acquisition workforce. This research proposes a matrix of training objectives and levels of competency for portions of the AT&L workforce that was validated through survey by individuals who are leading experts in both M&S and acquisition. This effort combines rigorously defined learning objectives and parameters by academia with practical learning insights from the military and industry ground perspectives. The resultant Joint Learning Model aims to identify the workforce educational foundations necessary to achieve more widespread efficiency and effectiveness in current and future DoD acquisitions.
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Date Issued: 2008
Identifier: CFE0002110, ucf:47536
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002110

Title: ULTRA-WIDE BAND IN COMMUNICATIONS: PERFORMANCE ANALYSIS AND ENHANCEMENTS.
Creator: Berksoy, Burak, WEI, Lei, University of Central Florida
Abstract / Description: Over the last ten years, Ultra-Wide Band (UWB) technology has attracted tremendous research attention. Frequency allocation of 3.1-10.6 GHz for UWB application by FCC made it apparent that UWB will be the technology for future wireless high speed communication applications. With the promise of high data rates (high channel capacity), UWB also offers advantages such as communication security, high multi-path resolution, good penetration capability, ability to coexist with other communication...
Show moreOver the last ten years, Ultra-Wide Band (UWB) technology has attracted tremendous research attention. Frequency allocation of 3.1-10.6 GHz for UWB application by FCC made it apparent that UWB will be the technology for future wireless high speed communication applications. With the promise of high data rates (high channel capacity), UWB also offers advantages such as communication security, high multi-path resolution, good penetration capability, ability to coexist with other communication schemes in the same band, and finally, circuit simplicity. The theoretical advantages of UWB has made it a great candidate for short distance communications, however, UWB communications have many challenges, for example, sub-nanosecond pulse generation, timing sensitivity of modulation and synchronization, flat antenna performance over a wide bandwidth, effect of existing systems on UWB systems. In order to experiment with various UWB modulation schemes, and to study transmitter and receiver structures, an accurate channel model need be established. In this dissertation, our first contribution is to evaluate and implement two major statistical channel models. The first model is proposed by AT\&T Labs and is in the form of an autoregressive IIR filter. Although this is an accurate channel model to represent UWB behavior, it is proposed before the allocation of 3.1-10.6 GHz frequency band, hence, it could not simulate the correct frequency spectrum. The second model is proposed by Saleh and Valenzuela, which has been widely accepted by UWB community to be the most accurate channel model for UWB systems. Recently disbanded task group 802.15.3a which was assigned to standardize a UWB communication scheme has also accepted the latter model. Our second contribution is to derive optimal pulses for PPM signals. Using the accurate channel model in computer simulations, we experimented on various UWB communication schemes. We found that the traditional UWB pulses being used in pulse position modulated UWB systems did not perform optimally. A set of optimized UWB pulses and the methodology to calculate optimal pulses for any modulation index for PPM systems have been proposed in this dissertation. It is found that the optimal pulse can improve the performance of UWB systems by as much as 0.7 dB. With the PPM pulse optimization, the theoretical performance limits of PPM systems are derived. The third contribution from this dissertation is to design near optimal practical implementable receiver structures. Some of the results obtained from PPM pulse optimization are found to be theoretical and not practical. More practical approach to the receiver structures were needed for industrial interest. We proposed simple sub-optimal receiver structures that are able to perform only a few dB less than the optimal receivers are proposed. These simple, low-cost receiver structures are strong alternatives to the complex traditional optimal receivers.
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Date Issued: 2008
Identifier: CFE0002106, ucf:47531
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002106

Title: THE RELATIONSHIP BETWEEN THE BASIC SKILLS PROFICIENCY OF COUNSELOR EDUCATION MASTER'S LEVEL STUDENTS AND CLIENT OUTCOME.
Creator: Welsh, Lorie, Robinson, Edward, University of Central Florida
Abstract / Description: A review of literature on the history of psychology and counseling revealed a limited amount of research on counselor education training programs, specifically basic skills versus client outcome. The purpose of this study was to investigate the relationship between counselor educator student's basic skills and the effects these skills had on client outcome. By way of a multiple regression, two independent variables, the Global Scale for Rating Helper Responses (GSRR) and the Counselor...
Show moreA review of literature on the history of psychology and counseling revealed a limited amount of research on counselor education training programs, specifically basic skills versus client outcome. The purpose of this study was to investigate the relationship between counselor educator student's basic skills and the effects these skills had on client outcome. By way of a multiple regression, two independent variables, the Global Scale for Rating Helper Responses (GSRR) and the Counselor Skills and Professional Behavior Scale (CSPBS) were analyzed in relation to the Outcome Questionnaire (OQ-45.2). Results indicated that there was no statistical significance between basic skills and client outcome.
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Date Issued: 2007
Identifier: CFE0001549, ucf:47126
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001549

Title: HOT CARRIER EFFECT ON LDMOS TRANSISTORS.
Creator: Jiang, Liangjun, Yuan, Jiann S., University of Central Florida
Abstract / Description: One of the main problems encountered when scaling down is the hot carrier induced degradation of MOSFETs. This problem has been studied intensively during the past decade, under both static and dynamic stress conditions. In this period it has evolved from a more or less academic research topic to one of the most stringent constraints guaranteeing the lifetime of sub-micron devices. New drain engineering technique leads to the extensive usage of lateral doped drain structures. In these devices...
Show moreOne of the main problems encountered when scaling down is the hot carrier induced degradation of MOSFETs. This problem has been studied intensively during the past decade, under both static and dynamic stress conditions. In this period it has evolved from a more or less academic research topic to one of the most stringent constraints guaranteeing the lifetime of sub-micron devices. New drain engineering technique leads to the extensive usage of lateral doped drain structures. In these devices the peak of the lateral field is lowered by reducing the doping concentration near the drain and by providing a smooth junction transition instead of an abrupt one. Therefore, the amount of hot carrier generation for a given supply voltage and the influence of a certain physical damage on the electrical characteristics is decreased dramatically. A complete understanding of the hot carrier degradation problem in sub-micron 0.25um LD MOSFETs is presented in this work. First we discuss the degradation mechanisms observed under, for circuit operation, somewhat artificial but well-controlled uniform-substrate hot electron and substrate hot-hole injection conditions. Then the more realistic case of static channel hot carrier degradation is treated, and some important process-related effects are illustrated, followed by the behavior under the most relevant case for real operation, namely dynamic degradation. An Accurate and practical parameter extraction is used to obtain the LD MOSFETs model parameters, with the experiment verification. Good agreement between the model simulation and experiment is achieved. The gate charge transfer performance is examined to demonstrate the hot carrier effect. Furthermore, In order to understand the dynamic stress on the LD MOSFET and its effect on RF circuit, the hot-carrier injection experiment in which dynamic stress with different duty cycle applied to a LD MOS transistor is presented. A Class-C power amplifier is used to as an example to demonstrate the effect of dynamic stress on RF circuit performance. Finally, the strategy for improving hot carrier reliability and a forecast of the hot carrier reliability problem for nano-technologies are discussed. The main contribution of this work is, it systemically research the hot carrier reliability issue on the sub-micron lateral doped drain MOSFETs, which is induced by static and dynamic voltage stress; The stress condition mimics the typical application scenarios of LD MOSFET. Model parameters extraction technique is introduced with the aid of the current device modeling tools, the performance degradation model can be easily implement into the existing computer-aided tools. Therefore, circuit performance degradation can be accurately estimated in the design stage. CMOS technologies are constantly scaled down. The production on 65 nm is on the market. With the reduction in geometries, the devices become more vulnerable to hot carrier injection (HCI). HCI reliability is a must for designs implemented with new processes. Reliability simulation needs to be implemented in PDK libraries located on the modeling stage. The use of professional tools is a prerequisite to develop accurate device models, from DC to GHz, including noise modeling and nonlinear HF effects, within a reasonable time. Designers need to learn to design for reliability and they should be educated on additional reliability analyses. The value is the reduction of failure and redesign costs.
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Date Issued: 2007
Identifier: CFE0001551, ucf:47148
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001551

Title: MODELING FREE CHLORINE AND CHLORAMINE DECAY IN A PILOT DISTRIBUTION SYSTEM.
Creator: Arevalo, Jorge, Taylor, James, University of Central Florida
Abstract / Description: The purpose of this study was to identify the effect that water quality, pipe material, pipe size, flow conditions and the use of corrosion inhibitors would have on the rate of free chlorine and chloramine decay in distribution systems. Empirical models were developed to predict the disinfectant residual concentration with time based on the parameters that affected it. Different water treatment processes were used to treat groundwater and surface water to obtain 7 types of finished waters...
Show moreThe purpose of this study was to identify the effect that water quality, pipe material, pipe size, flow conditions and the use of corrosion inhibitors would have on the rate of free chlorine and chloramine decay in distribution systems. Empirical models were developed to predict the disinfectant residual concentration with time based on the parameters that affected it. Different water treatment processes were used to treat groundwater and surface water to obtain 7 types of finished waters with a wide range of water quality characteristics. The groundwater was treated either by conventional treatment by aeration (G1) or softening (G2) or high pressure reverse osmosis (RO) and the surface water was treated either by enhanced coagulation, ozonation and GAC filtration (CSF-O3-GAC or S1) or an integrated membrane system (CSF-NF or S2). The remaining two water types were obtained by treating a blend of G1, S1 and RO by softening (S2) and nanofiltration (G4). A pilot distribution systems (PDS) consisting of eighteen (18) lines was built using old pipes obtained from existing distribution system. The pipe materials used were polyvinyl chloride (PVC), lined cast iron (LCI), unlined cast iron (UCI) and galvanized steel (G). During the first stage of the study, the 7 types of water were blended and fed to the PDS to study the effect of feed water quality changes on PDS effluent water quality, and specifically disinfectant residual. Both free chlorine and chloramines were used as disinfectant and the PDSs were operated at hydraulic retention times (HRT) of 2 and 5 days. The PDSs were periodically tested for free and combined chlorine, organic content, temperature, pH, turbidity and color. The data obtained were used to develop separate models for free chlorine and chloramines. The best fit model was a first-order kinetic model with respect to initial disinfectant concentration that is dependent on the pipe material, pipe diameter and the organic content and temperature of the water. Turbidity, color and pH were found to be not significant for the range of values observed. The models contain two decay constants, the first constant (KB) accounts for the decay due to reaction in the bulk liquid and is affected by the organics and temperature while the second constant, KW, represents the reactions at the pipe wall and is affected by the temperature of the water and the pipe material and diameter. The rate of free chlorine and chloramine decay was found to be highly affected by the pipe material, the decay was faster in unlined metallic pipes (UCI and G) and slower in the synthetic (PVC) and lined pipes (LCI). The models showed that the rate of disinfectant residual loss increases with the increase of temperature or the organics in the water irrespective of pipe material. During the second part of the study, corrosion control inhibitors were added to a blend of S1, G1 and RO that fed all the hybrid PDSs. The inhibitors used were: orthophosphate, blended ortho-polyphosphate, zinc orthophosphate and sodium silicate. Three PDSs were used for each inhibitor type, for a total of 12 PDSs, to study the effect of low, medium and high dose on water quality. Two PDSs were used as control, fed with the blend without any inhibitor addition. The control PDSs were used to observe the effect of pH control on water quality and compare to the inhibitor use. One of the control PDSs (called PDS 13) had the pH adjusted to be equal to the saturation pH in relation to calcium carbonate precipitation (pHs) while the pH of the other control PDS (PDS 14) was adjusted to be 0.3 pH units above the pHs. The disinfectant used for this part of the study was chloramine and the flow rates were set to obtain a HRT of 2 days. The chloramine demand was the same for PDS 14 and all the PDSs receiving inhibitors. PDS 13 had a chloramine demand greater than any other PDS. The lowest chloramine demand was observed in PDS 12, which received silicate inhibitor at a dose of 12 mg/L, and presented the highest pH. The elevation of pH of the water seems to reduce the rate of decay of chloramines while the use of corrosion inhibitors did not have any effect. on the rate of chloramine decay. The PDS were monitored for chloramine residual, temperature, pH, phosphate, reactive silica, and organic content. Empirical models were developed for the dissipation of chloramine in the pilot distribution systems as a function of time, pipe material, pipe diameter and water quality. Terms accounting for the effect of pH and the type and dose of corrosion inhibitor were included in the model. The use of phosphate-based or silica-based corrosion inhibitors was found to have no effect on the rate of chloramine dissipation in any of the pipe materials. Only the increase of pH was found to decrease the rate of chloramine decay. The model to best describe the decay of chloramine in the pilot distribution systems was a first-order kinetic model containing separate rate constants for the bulk reactions, pH effect and the pipe wall reactions. The rate of chloramine decay was dependent on the material and diameter of the pipe, and the temperature, pH and organic content of the water. The rate of chloramine decay was low for PVC and LCI, and more elevated in UCI and G pipes. Small diameter pipes and higher temperatures increase the rate of chlorine decay irrespective of pipe material. Additional experiments were conducted to evaluate the effect of flow velocity on chloramine decay in a pilot distribution system (PDS) for different pipe materials and water qualities. The experiments were done using the single material lines and the flow velocity of the water was varied to obtain Reynolds' numbers from 50 to 8000. A subset of experiments included the addition of blended orthophosphate corrosion inhibitor (BOP) at a dose of 1.0 mg/L as P to evaluate the effect of the inhibitor on chloramine decay. The effect of Reynolds' number on the overall chloramine decay rate (K) and the wall decay rate constant (W) was assessed for PVC, LCI, UCI, and G pipes. PVC and LCI showed no change on the rate of chloramine decay at any flow velocity. UCI and G pipes showed a rapid increase on the wall decay rate under laminar conditions (Re < 500) followed by a more gradual increase under fully turbulent flow conditions (Re > 2000). The use of the BOP inhibitor did not have an effect on the rate of chloramine decay for any of the pipe materials studied. Linear correlations were developed to adjust the rate of chloramine decay at the pipe wall for UCI and G depending on the Reynolds' number.
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Date Issued: 2007
Identifier: CFE0001863, ucf:47400
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001863

Title: REAL-TIME TREE SIMULATION USING VERLET INTEGRATION.
Creator: Manavi, Bobak, Kincaid, J. Peter, University of Central Florida
Abstract / Description: One of the most important challenges in real-time simulation of large trees and vegetation is the vast number of calculations required to simulate the interactions between all the branches in the tree when external forces are applied to it. This paper will propose the use of algorithms employed by applications like cloth and soft body simulations, where objects can be represented by a finite system of particles connected via spring-like constraints, for the structural representation and...
Show moreOne of the most important challenges in real-time simulation of large trees and vegetation is the vast number of calculations required to simulate the interactions between all the branches in the tree when external forces are applied to it. This paper will propose the use of algorithms employed by applications like cloth and soft body simulations, where objects can be represented by a finite system of particles connected via spring-like constraints, for the structural representation and manipulation of trees in real-time. We will then derive and show the use of Verlet integration and the constraint configuration used for simulating trees while constructing the necessary data structures that encapsulate the procedural creation of these objects. Furthermore, we will utilize this system to simulate branch breakage due to accumulated external and internal pressure.
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Date Issued: 2007
Identifier: CFE0001802, ucf:47381
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001802

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