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Title: Research into Modular Construction.
Creator: Tash, Richard L., Block, David T., Engineering
Abstract / Description: Florida Technological University College of Engineering Thesis
Date Issued: 1972
Identifier: CFR0011994, ucf:53088
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0011994

Title: The Impact of Relational Coordination and the Nurse on Patient Outcomes.
Creator: Dejesus, Fanya, Andrews, Diane, Sole, Mary Lou, Neff, Donna, Yan, Xin, Unruh, Lynn, University of Central Florida
Abstract / Description: Healthcare quality remains a significant issue due to fragmentation of care in our complex U.S. healthcare systems. While coordination of care is foundational to healthcare quality as well as identified as a National Priority, fragmentation and uncoordinated care continues to afflict our systems. The purpose of this study was to explore the relationship between relational coordination and adverse nurse sensitive patient outcomes, namely hospital acquired pressure ulcers, patient falls with...
Show moreHealthcare quality remains a significant issue due to fragmentation of care in our complex U.S. healthcare systems. While coordination of care is foundational to healthcare quality as well as identified as a National Priority, fragmentation and uncoordinated care continues to afflict our systems. The purpose of this study was to explore the relationship between relational coordination and adverse nurse sensitive patient outcomes, namely hospital acquired pressure ulcers, patient falls with injury, catheter- associated urinary tract infection, and central line-associated blood stream infection. A retrospective correlational survey design using cross sectional data was used to conduct this quantitative study. An electronic relational coordination survey was sent to 1124 eligible registered nurses from 43 nursing units within a 5-hospital magnet-designated healthcare system to gather their perception of the strength of relationship and communication ties of their work team. The nurse practice environment as well as nurse education were control variables. With 406 nurses who completed the survey (36% response rate), findings revealed that the stronger relational coordination ties are amongst the healthcare team, the lower the rate of adverse nurse sensitive patient outcomes as indicated by their inverse relationship. (rs=-.31, p=.050). In a Negative Binomial Regression model, relational coordination was a significant predictor (?-1.890, p=.034) of nurse sensitive patient outcomes whereas nurse education level (p=.859) and nurse practice environment (p=.230) were not. Data affirms that relational coordination, a relationship and communication intensive form of coordination does impact patient outcomes. This research provides significant information to health care leaders and institutions with goals of improving patient care outcomes through enhancement of coordination of care and optimization of healthcare teams.
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Date Issued: 2015
Identifier: CFE0005939, ucf:50823
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005939

Title: MANAGING THE CHARACTERISTICS OF SOFTWARE PRODUCT DEVELOPMENT PROGRAMS.
Creator: Li, Yuzhu, Jiang, James, University of Central Florida
Abstract / Description: Multiple related software development projects are often managed concurrently and systematically to deliver a complex software system. This approach of managing multiple interdependent projects together to achieve a common goal is called program management (Pellegrinelli, 1997). A software development program can generate the benefits that cannot be achieved by managing projects individually. The software product development program has the special characteristics such as complexity,...
Show moreMultiple related software development projects are often managed concurrently and systematically to deliver a complex software system. This approach of managing multiple interdependent projects together to achieve a common goal is called program management (Pellegrinelli, 1997). A software development program can generate the benefits that cannot be achieved by managing projects individually. The software product development program has the special characteristics such as complexity, uncertainty and interdependence (1995). A software product development program can play an active role in managing the uncertainty and interdependence in the software development process. This dissertation is designed to examine the external communication effectiveness of the program team on the interdependence between the program and the larger organizational context. In addition, this dissertation studies the inter-project coordination effectiveness on uncertainty within a program. Based upon organizational Information Processing Theory (IPT) and Resource Dependence Theory (RDT), theoretical frameworks are developed. The proposed research models are tested by surveying software product development programs across a range of industries. The results will contribute to the understanding of multiple-project communication in a program's context. The specific interactions between coordination/communication and the product development characteristics will provide a guideline for the industrial practices.
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Date Issued: 2008
Identifier: CFE0002305, ucf:47866
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002305

Title: Energy efficient routing towards a mobile sink using virtual coordinates in a wireless sensor network.
Creator: Rahmatizadeh, Rouhollah, Boloni, Ladislau, Turgut, Damla, Jha, Sumit, University of Central Florida
Abstract / Description: The existence of a coordinate system can often improve the routing in a wireless sensor network. While most coordinate systems correspond to the geometrical or geographical coordinates, in recent years researchers had proposed the use of virtual coordinates. Virtual coordinates depend only on the topology of the network as defined by the connectivity of the nodes, without requiring geographical information. The work in this thesis extends the use of virtual coordinates to scenarios where the...
Show moreThe existence of a coordinate system can often improve the routing in a wireless sensor network. While most coordinate systems correspond to the geometrical or geographical coordinates, in recent years researchers had proposed the use of virtual coordinates. Virtual coordinates depend only on the topology of the network as defined by the connectivity of the nodes, without requiring geographical information. The work in this thesis extends the use of virtual coordinates to scenarios where the wireless sensor network has a mobile sink. One reason to use a mobile sink is to distribute the energy consumption more evenly among the sensor nodes and thus extend the life-time of the network. We developed two algorithms, MS-DVCR and CU-DVCR which perform routing towards a mobile sink using virtual coordinates. In contrast to the baseline virtual coordinate routing MS-DVCR limits routing updates triggered by the sink movement to a local area around the sink. In contrast, CU-DVCR limits the route updates to a circular area on the boundary of the local area. We describe the design justification and the implementation of these algorithms. Using a set of experimental studies, we show that MS-DVCR and CU-DVCR achieve a lower energy consumption compared to the baseline virtual coordinate routing without any noticeable impact on routing performance. In addition, CU-DVCR provides a lower energy consumption than MS-DVCR for the case of a fast moving sink.
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Date Issued: 2014
Identifier: CFE0005402, ucf:50422
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005402

Title: COORDINATION, MATCHMAKING, AND RESOURCE ALLOCATION FOR LARGE-SCALE DISTRIBUTED SYSTEMS.
Creator: Bai, Xin, Marinescu, Dan, University of Central Florida
Abstract / Description: While existing grid environments cater to specific needs of a particular user community, we need to go beyond them and consider general-purpose large-scale distributed systems consisting of large collections of heterogeneous computers and communication systems shared by a large user population with very diverse requirements. Coordination, matchmaking, and resource allocation are among the essential functions of large-scale distributed systems. Although deterministic approaches for...
Show moreWhile existing grid environments cater to specific needs of a particular user community, we need to go beyond them and consider general-purpose large-scale distributed systems consisting of large collections of heterogeneous computers and communication systems shared by a large user population with very diverse requirements. Coordination, matchmaking, and resource allocation are among the essential functions of large-scale distributed systems. Although deterministic approaches for coordination, matchmaking, and resource allocation have been well studied, they are not suitable for large-scale distributed systems due to the large-scale, the autonomy, and the dynamics of the systems. We have to seek for nondeterministic solutions for large-scale distributed systems. In this dissertation we describe our work on a coordination service, a matchmaking service, and a macro-economic resource allocation model for large-scale distributed systems. The coordination service coordinates the execution of complex tasks in a dynamic environment, the matchmaking service supports finding the appropriate resources for users, and the macro-economic resource allocation model allows a broker to mediate resource providers who want to maximize their revenues and resource consumers who want to get the best resources at the lowest possible price, with some global objectives, e.g., to maximize the resource utilization of the system.
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Date Issued: 2006
Identifier: CFE0001172, ucf:46845
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001172

Title: AMERICAN AGRIBUSINESS AND BIOTECHNOLOGY: A NEW ERA OF FARMING.
Creator: Ryan, Nicole M, Sadri, Houman, University of Central Florida
Abstract / Description: In the past fifty years there has been an incredible amount of change made to the agrarian system of the United States. New discoveries in the realm of biotechnology led to the adoption of genetically modified organisms (GMOs) in agriculture, and transformed the industry. Due to regulatory policies set during the nineteen-eighties this technology was able to benefit from widespread commercialization. Today, we see the effects of this approach and are entering into a highly volatile political...
Show moreIn the past fifty years there has been an incredible amount of change made to the agrarian system of the United States. New discoveries in the realm of biotechnology led to the adoption of genetically modified organisms (GMOs) in agriculture, and transformed the industry. Due to regulatory policies set during the nineteen-eighties this technology was able to benefit from widespread commercialization. Today, we see the effects of this approach and are entering into a highly volatile political climate in regard to GMOs. This paper aims to provide an analysis of the regulatory system in place and the discrepancies that exist in US policy. The factors evaluated through this thesis include the current US regulatory approach, advancements in biotechnology, and a comparative perspective on US and EU systems. In each of these reviews it is also relevant to mention consumer opinion on GMOs and the role of interest groups. It is important for every American consumer to understand the politics and technology behind their meals. Through the analysis of recent judicial decisions and the enactment of new laws this thesis explains how the use of GMOs in agriculture is causing an unprecedented change to the political structures in place.
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Date Issued: 2016
Identifier: CFH2000035, ucf:45586
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000035

Title: UNDERSTANDING THE ROLE OF SOCIAL CAPITAL IN EXPERTISE COORDINATION IN INFORMATION SYSTEMS DEVELOPMENT (ISD) TEAMS.
Creator: Hsu, Shih-Chieh, Jiang, James, University of Central Florida
Abstract / Description: Information system development (ISD) project is a knowledge-intensive teamwork process which requires members to coordinate their expertise to generate the final outcome. Breakdown or coordination and insufficient knowledge integration have been reported as critical factors which lead to ISD project failure. Most existing coordination literature focus on the effect of administrative coordination mechanisms toward project performance which hints that more efforts are needed to understand...
Show moreInformation system development (ISD) project is a knowledge-intensive teamwork process which requires members to coordinate their expertise to generate the final outcome. Breakdown or coordination and insufficient knowledge integration have been reported as critical factors which lead to ISD project failure. Most existing coordination literature focus on the effect of administrative coordination mechanisms toward project performance which hints that more efforts are needed to understand expertise coordination and explore ways to improve it. Addressing the above issues, two studies in this dissertation attempt to understand expertise coordination within the IS development team based on social capital perspective. The first study, based on intention-behavior literature, knowledge management research, and Gerwin's (2004) coordination model, investigates relationships among willingness, competence, and actual expertise coordination. The relationships between expertise coordination and teamwork outcomes are also examined. The second study incorporates social capital theory and examines (1) dependencies among three dimensions of social capital and (2) linkage between social capital and expertise coordination. Data collected from more than five hundred information systems project team members was used to test the proposed hypotheses. The analysis results confirmed most of the hypotheses. This dissertation contributes to coordination, project management, and team mental model research through many perspectives. In each study, directions for management practice and future research are discussed.
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Date Issued: 2008
Identifier: CFE0002347, ucf:47816
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002347

Title: TOWARDS A SELF-CALIBRATING VIDEO CAMERA NETWORK FOR CONTENT ANALYSIS AND FORENSICS.
Creator: Junejo, Imran, Foroosh, Hassan, University of Central Florida
Abstract / Description: Due to growing security concerns, video surveillance and monitoring has received an immense attention from both federal agencies and private firms. The main concern is that a single camera, even if allowed to rotate or translate, is not sufficient to cover a large area for video surveillance. A more general solution with wide range of applications is to allow the deployed cameras to have a non-overlapping field of view (FoV) and to, if possible, allow these cameras to move freely in 3D space....
Show moreDue to growing security concerns, video surveillance and monitoring has received an immense attention from both federal agencies and private firms. The main concern is that a single camera, even if allowed to rotate or translate, is not sufficient to cover a large area for video surveillance. A more general solution with wide range of applications is to allow the deployed cameras to have a non-overlapping field of view (FoV) and to, if possible, allow these cameras to move freely in 3D space. This thesis addresses the issue of how cameras in such a network can be calibrated and how the network as a whole can be calibrated, such that each camera as a unit in the network is aware of its orientation with respect to all the other cameras in the network. Different types of cameras might be present in a multiple camera network and novel techniques are presented for efficient calibration of these cameras. Specifically: (i) For a stationary camera, we derive new constraints on the Image of the Absolute Conic (IAC). These new constraints are shown to be intrinsic to IAC; (ii) For a scene where object shadows are cast on a ground plane, we track the shadows on the ground plane cast by at least two unknown stationary points, and utilize the tracked shadow positions to compute the horizon line and hence compute the camera intrinsic and extrinsic parameters; (iii) A novel solution to a scenario where a camera is observing pedestrians is presented. The uniqueness of formulation lies in recognizing two harmonic homologies present in the geometry obtained by observing pedestrians; (iv) For a freely moving camera, a novel practical method is proposed for its self-calibration which even allows it to change its internal parameters by zooming; and (v) due to the increased application of the pan-tilt-zoom (PTZ) cameras, a technique is presented that uses only two images to estimate five camera parameters. For an automatically configurable multi-camera network, having non-overlapping field of view and possibly containing moving cameras, a practical framework is proposed that determines the geometry of such a dynamic camera network. It is shown that only one automatically computed vanishing point and a line lying on any plane orthogonal to the vertical direction is sufficient to infer the geometry of a dynamic network. Our method generalizes previous work which considers restricted camera motions. Using minimal assumptions, we are able to successfully demonstrate promising results on synthetic as well as on real data. Applications to path modeling, GPS coordinate estimation, and configuring mixed-reality environment are explored.
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Date Issued: 2007
Identifier: CFE0001743, ucf:47296
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001743

Title: INVESTIGATING THE MECHANISMS THAT DRIVE IMPLICIT COORDINATION IN TEAMS.
Creator: Hoeft, Raegan, Jentsch, Florian, University of Central Florida
Abstract / Description: The purpose of this study was to empirically test the oft-noted hypothesis that shared mental models lead to implicit coordination. Specifically, this dissertation investigated the underlying mechanisms of implicit coordination and how different aspects of shared mental models affect the process. The research questions tested in this study were (a)how perceptions of sharedness affect the initiation of implicit coordination, (b) how actual levels of sharedness affect the process of implicit...
Show moreThe purpose of this study was to empirically test the oft-noted hypothesis that shared mental models lead to implicit coordination. Specifically, this dissertation investigated the underlying mechanisms of implicit coordination and how different aspects of shared mental models affect the process. The research questions tested in this study were (a)how perceptions of sharedness affect the initiation of implicit coordination, (b) how actual levels of sharedness affect the process of implicit coordination, and (c) how quality of task mental models affects successful implicit coordination. Sixty same-gender, two-person teams engaged in a complex military reconnaissance planning task in which the team members were required to work together by exchanging information to plan routes for one unmanned aerial vehicle (UAV) and one unmanned ground vehicle (UGV). The results provided partial support for the influence of different facets of shared mental models on the process of implicit coordination. Specifically, individual mental model quality, not perceptions of sharedness or actual mental model sharedness, was the biggest predictor of the initiation of implicit coordination. Additionally, perceptions of sharedness and actual mental model sharedness interacted with one another, such that teams in mismatched conditions (high perceptions of sharedness but low actual sharedness [false consensus], or low perceptions of sharedness and high actual sharedness, [pluralistic ignorance]) tended to increase their communications. The implications and recommendations for future research on implicit coordination and shared mental models are discussed. Additionally, the implications for operators of unmanned vehicles are also discussed.
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Date Issued: 2006
Identifier: CFE0001181, ucf:46857
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001181

Title: IMPACT OF RETURNS POLICIES AND GROUP-BUYING ON CHANNEL COORDINATION.
Creator: Tran, Thanh, Desiraju, Ramarao, University of Central Florida
Abstract / Description: This dissertation investigates the role of two marketing practices---returns policies and group-buying services---in improving channel coordination. The first study (presented in Chapter Two) focuses on the interaction between two types of returns policies---returns of unwanted products from consumers to retailers and returns of unsold inventory from retailers to manufacturers. Even without the right to return unsold inventory to the manufacturer, the retailers may accept returns from...
Show moreThis dissertation investigates the role of two marketing practices---returns policies and group-buying services---in improving channel coordination. The first study (presented in Chapter Two) focuses on the interaction between two types of returns policies---returns of unwanted products from consumers to retailers and returns of unsold inventory from retailers to manufacturers. Even without the right to return unsold inventory to the manufacturer, the retailers may accept returns from consumers; by doing so, they benefit from a less price-sensitive market demand, an ability to screen for high-valuation consumers, and a competitive advantage (offering a returns policy makes a retailer more attractive to consumers). From the manufacturer's perspective, accepting returns may induce the retailers to order more stock, set lower prices, generate more sales, and therefore, improves the performance of the channel. However, under some conditions (e.g., when the marginal cost of stock-outs is relatively high), this study shows that this effect disappears and the manufacturer does not accept returns from the retailer in equilibrium. The second study (presented in Chapter Three) investigates the rationale for using group-buying services vis-a-vis the traditional posted-pricing mechanism. It focuses on the behavior of consumers and explores the role of heterogeneity in their valuation for the product and cost of purchasing via group-buying in the functioning of group-buying services as a price-discrimination device. Finally, the role of group-buying services in improving channel coordination under asymmetric information is studied in Chapter Four. This analysis shows that the availability of group-buying services provides an opportunity for the manufacturer to reduce the informational rents of the retailer arising from its private information about the market condition. Interestingly, the manufacturer can avoid paying these rents and regains the first-best profitability when asymmetry in information exists regarding the relative sizes of consumer segments. In other settings (e.g., when asymmetric information exists regarding consumers' price sensitivity), leveraging the group-buying mechanism nevertheless allows the manufacturer to design a contract that requires lower rents and improves channel coordination to some extent.
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Date Issued: 2009
Identifier: CFE0002747, ucf:48182
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002747

Title: An Examination of the Florida Linking Individuals Needing Care Coordination Program for Racial and Ethnic Minority Females.
Creator: Vance, Michelle, Gryglewicz, Kimberley, Chapple, Reshawna, Lawrence, Shawn, Fisher, Kristina Childs, University of Central Florida
Abstract / Description: Suicide accounts for close to 800,000 deaths each year, making it one of the leading causes of death in the United States. In the state of Florida, suicide is the 10th leading cause of death. Currently, it is the 2nd leading cause of death among young people ages 15-29, claiming more lives than homicide. Among Black and Hispanic youth (10 to 24), it is the 2nd and 3rd leading causes of death. This study aimed to examine the extent to which depression and suicidality outcomes change among...
Show moreSuicide accounts for close to 800,000 deaths each year, making it one of the leading causes of death in the United States. In the state of Florida, suicide is the 10th leading cause of death. Currently, it is the 2nd leading cause of death among young people ages 15-29, claiming more lives than homicide. Among Black and Hispanic youth (10 to 24), it is the 2nd and 3rd leading causes of death. This study aimed to examine the extent to which depression and suicidality outcomes change among racial and ethnic minority females (i.e., Black and African American, Hispanic) who participated in a care coordination intervention. These subpopulations were chosen due to limited suicide prevention research on at-risk racial and ethnic minority females and to address health disparities. To examine these outcomes, the study employed a one-group pretest-posttest design utilizing secondary data from 76 youth participants enrolled in the care coordination program from three crisis stabilization units (CSU) in Florida. Key findings included significant decreases in depression symptomology (54%) and suicidality (82%). Among participants enrolled in the program, 84% did not have a readmission to the CSU. Length of stay was a predictor or readmission in that a one unit (one day) increase lead to a 3% increase in odds of readmission to the CSU. Results of this study can help guide social work and mental health practitioners in designing and implementing community-based suicide prevention programs for racial and ethnic minority females.
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Date Issued: 2019
Identifier: CFE0007548, ucf:52594
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007548

Title: Team Interaction Dynamics during Collaborative Problem Solving.
Creator: Wiltshire, Travis, Fiore, Stephen, Jentsch, Florian, Salas, Eduardo, Wiegand, Rudolf, University of Central Florida
Abstract / Description: This dissertation contributes an enhanced understanding of team cognition, in general, and collaborative problem solving (CPS), specifically, through an integration of methods that measure team interaction dynamics and knowledge building as it occurs during a complex CPS task. The need for better understanding CPS has risen in prominence as many organizations have increasingly worked to address complex problems requiring the combination of diverse sets of individual expertise to achieve...
Show moreThis dissertation contributes an enhanced understanding of team cognition, in general, and collaborative problem solving (CPS), specifically, through an integration of methods that measure team interaction dynamics and knowledge building as it occurs during a complex CPS task. The need for better understanding CPS has risen in prominence as many organizations have increasingly worked to address complex problems requiring the combination of diverse sets of individual expertise to achieve solutions for novel problems. Towards this end, the present research drew from theoretical and empirical work on Macrocognition in Teams that describes the knowledge coordination arising from team communications during CPS. It built from this by incorporating the study of team interaction during complex collaborative cognition. Interaction between team members in such contexts has proven to be inherently dynamic and exhibiting nonlinear patterns not accounted for by extant research methods. To redress this gap, the present research drew from work in cognitive science designed to study social and team interaction as a nonlinear dynamical system. CPS was examined by studying knowledge building and interaction processes of 43 dyads working on NASA's Moonbase Alpha simulation, a CPS task. Both non-verbal and verbal interaction dynamics were examined. Specifically, frame-differencing, an automated video analysis technique, was used to capture the bodily movements of participants and content coding was applied to the teams' communications to characterize their CPS processes. A combination of linear (i.e., multiple regression, t-test, and time-lagged cross-correlation analysis), as well as nonlinear analytic techniques (i.e., recurrence quantification analysis; RQA) were applied. In terms of the predicted interaction dynamics, it was hypothesized that teams would exhibit synchronization in their bodily movements and complementarity in their communications and further, that teams more strongly exhibiting these forms of coordination will produce better problem solving outcomes. Results showed that teams did exhibit a pattern of bodily movements that could be characterized as synchronized, but higher synchronization was not systematically related to performance. Further, results showed that teams did exhibit communicative interaction that was complementary, but this was not predictive of better problem solving performance. Several exploratory research questions were proposed as a way of refining the application of these techniques to the investigation of CPS. Results showed that semantic code-based communications time-series and %REC and ENTROPY recurrence-based measures were most sensitive to differences in performance. Overall, this dissertation adds to the scientific body of knowledge by advancing theory and empirical knowledge on the forms of verbal and non-verbal team interaction during CPS, but future work remains to be conducted to identify the relationship between interaction dynamics and CPS performance.
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Date Issued: 2015
Identifier: CFE0005907, ucf:50867
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005907

Title: Chaotification as a Means of Broadband Vibration Energy Harvesting with Piezoelectric Materials.
Creator: Geiyer, Daniel, Kauffman, Jeffrey L., Das, Tuhin, Moslehy, Faissal, Shivamoggi, Bhimsen, University of Central Florida
Abstract / Description: Computing advances and component miniaturization in circuits coupled with stagnating battery technology have fueled growth in the development of high efficiency energy harvesters. Vibration-to-electricity energy harvesting techniques have been investigated extensively for use in sensors embedded in structures or in hard-to-reach locations like turbomachinery, surgical implants, and GPS animal trackers. Piezoelectric materials are commonly used in harvesters as they possess the ability to...
Show moreComputing advances and component miniaturization in circuits coupled with stagnating battery technology have fueled growth in the development of high efficiency energy harvesters. Vibration-to-electricity energy harvesting techniques have been investigated extensively for use in sensors embedded in structures or in hard-to-reach locations like turbomachinery, surgical implants, and GPS animal trackers. Piezoelectric materials are commonly used in harvesters as they possess the ability to convert strain energy directly into electrical energy and can work concurrently as actuators for damping applications. The prototypical harvesting system places two piezoelectric patches on both sides of the location of maximum strain on a cantilever beam. While efficient around resonance, performance drops dramatically should the driving frequency drift away from the beam's fundamental frequency. To date, researchers have worked to improve harvesting capability by modifying material properties, using alternative geometries, creating more efficient harvesting circuits, and inducing nonlinearities. These techniques have partially mitigated the resonance excitation dependence for vibration-based harvesting, but much work remains.In this dissertation, an induced nonlinearity destabilizes a central equilibrium point, resulting in a bistable potential function governing the cantilever beam system. Depending on the environment, multiple stable solutions are possible and can coexist. Typically, researchers neglect chaos and assume that with enough energy in the ambient environment, large displacement trajectories can exist uniquely. When subjected to disturbances a system can fall to coexistent lower energy solutions including aperiodic, chaotic oscillations. Treating chaotic motion as a desirable behavior of the system allows frequency content away from resonance to produce motion about a theoretically infinite number of unstable periodic orbits that can be stabilized through control. The extreme sensitivity to initial conditions exhibited by chaotic systems paired with a pole placement control strategy pioneered by Ott, Grebogi, and Yorke permits small perturbations to an accessible system parameter to alter the system response dramatically. Periodic perturbation of the system trajectories in the vicinity of isolated unstable orbit points can therefore stabilize low-energy chaotic oscillations onto larger trajectory orbits more suitable for energy harvesting.The periodic perturbation-based control method rids the need of a system model. It only requires discrete displacement, velocity, or voltage time series data of the chaotic system driven by harmonic excitation. While the analysis techniques are not fundamentally limited to harmonic excitation, this condition permits the use of standard discrete mapping techniques to isolate periodic orbits of interest. Local linear model fits characterize the orbit and admit the necessary control perturbation calculations from the time series data.This work discusses the feasibility of such a method for vibration energy harvesting, displays stable solutions under various control algorithms, and implements a hybrid bench-top experiment using MATLAB and LabVIEW FPGA. In conclusion, this work discusses the limitations for wide-scale use and addresses areas of further work; both with respect to chaotic energy harvesting and parallel advances required within the field as a whole.
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Date Issued: 2017
Identifier: CFE0006878, ucf:51718
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006878

Title: Sparse Ridge Fusion For Linear Regression.
Creator: Mahmood, Nozad, Maboudou, Edgard, Schott, James, Uddin, Nizam, University of Central Florida
Abstract / Description: For a linear regression, the traditional technique deals with a case where the number of observations n more than the number of predictor variables p (n(>)p). In the case n(
Show moreFor a linear regression, the traditional technique deals with a case where the number of observations n more than the number of predictor variables p (n(>)p). In the case n(<)p, the classical method fails to estimate the coefficients. A solution of this problem in the case of correlated predictors is provided in this thesis. A new regularization and variable selection is proposed under the name of Sparse Ridge Fusion (SRF). In the case of highly correlated predictor , the simulated examples and a real data show that the SRF always outperforms the lasso, elastic net, and the S-Lasso, and the results show that the SRF selects more predictor variables than the sample size n while the maximum selected variables by lasso is n size.
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Date Issued: 2013
Identifier: CFE0005031, ucf:49997
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005031

Title: EXPLOITING OPPONENT MODELING FOR LEARNING IN MULTI-AGENT ADVERSARIAL GAMES.
Creator: Laviers, Kennard, Sukthankar, Gita, University of Central Florida
Abstract / Description: An issue with learning effective policies in multi-agent adversarial games is that the size of the search space can be prohibitively large when the actions of both teammates and opponents are considered simultaneously. Opponent modeling, predicting an opponent's actions in advance of execution, is one approach for selecting actions in adversarial settings, but it is often performed in an ad hoc way. In this dissertation, we introduce several methods for using opponent modeling, in the form of...
Show moreAn issue with learning effective policies in multi-agent adversarial games is that the size of the search space can be prohibitively large when the actions of both teammates and opponents are considered simultaneously. Opponent modeling, predicting an opponent's actions in advance of execution, is one approach for selecting actions in adversarial settings, but it is often performed in an ad hoc way. In this dissertation, we introduce several methods for using opponent modeling, in the form of predictions about the players' physical movements, to learn team policies. To explore the problem of decision-making in multi-agent adversarial scenarios, we use our approach for both offline play generation and real-time team response in the Rush 2008 American football simulator. Simultaneously predicting the movement trajectories, future reward, and play strategies of multiple players in real-time is a daunting task but we illustrate how it is possible to divide and conquer this problem with an assortment of data-driven models. By leveraging spatio-temporal traces of player movements, we learn discriminative models of defensive play for opponent modeling. With the reward information from previous play matchups, we use a modified version of UCT (Upper Conference Bounds applied to Trees) to create new offensive plays and to learn play repairs to counter predicted opponent actions. In team games, players must coordinate effectively to accomplish tasks while foiling their opponents either in a preplanned or emergent manner. An effective team policy must generate the necessary coordination, yet considering all possibilities for creating coordinating subgroups is computationally infeasible. Automatically identifying and preserving the coordination between key subgroups of teammates can make search more productive by pruning policies that disrupt these relationships. We demonstrate that combining opponent modeling with automatic subgroup identification can be used to create team policies with a higher average yardage than either the baseline game or domain-specific heuristics.
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Date Issued: 2011
Identifier: CFE0003914, ucf:48720
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003914

Title: TOWARD A THEORY OF PRACTICAL DRIFT IN TEAMS.
Creator: Bisbey, Tiffany, Salas, Eduardo, University of Central Florida
Abstract / Description: Practical drift is defined as the unintentional adaptation of routine behaviors from written procedure. The occurrence of practical drift can result in catastrophic disaster in high-reliability organizations (e.g. the military, emergency medicine, space exploration). Given the lack of empirical research on practical drift, this research sought to develop a better understanding by investigating ways to assess and stop the process in high-reliability organizations. An introductory literature...
Show morePractical drift is defined as the unintentional adaptation of routine behaviors from written procedure. The occurrence of practical drift can result in catastrophic disaster in high-reliability organizations (e.g. the military, emergency medicine, space exploration). Given the lack of empirical research on practical drift, this research sought to develop a better understanding by investigating ways to assess and stop the process in high-reliability organizations. An introductory literature review was conducted to investigate the variables that play a role in the occurrence of practical drift in teams. Research was guided by the input-throughput-output model of team adaptation posed by Burke, Stagl, Salas, Pierce, and Kendall (2006). It demonstrates relationships supported by the results of the literature review and the Burke and colleagues (2006) model denoting potential indicators of practical drift in teams. Research centralized on the core processes and emergent states of the adaptive cycle; namely, shared mental models, team situation awareness, and coordination. The resulting model shows the relationship of procedure—practice coupling demands misfit and maladaptive violations of procedure being mediated by shared mental models, team situation awareness, and coordination. Shared mental models also lead to team situation awareness, and both depict a mutual, positive relationship with coordination. The cycle restarts when an error caused by maladaptive violations of procedure creates a greater misfit between procedural demands and practical demands. This movement toward a theory of practical drift in teams provides a conceptual framework and testable propositions for future research to build from, giving practical avenues to predict and prevent accidents resulting from drift in high-reliability organizations. Suggestions for future research are also discussed, including possible directions to explore. By examining the relationships reflected in the new model, steps can be taken to counteract organizational failures in the process of practical drift in teams.
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Date Issued: 2014
Identifier: CFH0004636, ucf:45300
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004636

Title: INTERNATIONAL SPACE STATION REMOTE SENSING POINTING ANALYSIS.
Creator: Jacobson, Craig, Leonessa, Alexander, University of Central Florida
Abstract / Description: This paper analyzes the geometric and disturbance aspects of utilizing the International Space Station for remote sensing of earth targets. The proposed instrument is SHORE (Station High-Sensitivity Ocean Research Experiment), a multi-band optical spectrometer with 15 m pixel resolution. The analysis investigates the contribution of the error effects to the quality of data collected by the instrument. The analysis begins with the discussion of the coordinate systems involved and then...
Show moreThis paper analyzes the geometric and disturbance aspects of utilizing the International Space Station for remote sensing of earth targets. The proposed instrument is SHORE (Station High-Sensitivity Ocean Research Experiment), a multi-band optical spectrometer with 15 m pixel resolution. The analysis investigates the contribution of the error effects to the quality of data collected by the instrument. The analysis begins with the discussion of the coordinate systems involved and then conversion from the target coordinate system to the instrument coordinate system. Next the geometry of remote observations from the Space Station is investigated including the effects of the instrument location in Space Station and the effects of the line of sight to the target. The disturbance and error environment on Space Station is discussed covering factors contributing to drift and jitter, accuracy of pointing data and target and instrument accuracies. Finally, there is a brief discussion of image processing to address any post error correction options.
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Date Issued: 2005
Identifier: CFE0000855, ucf:46661
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000855

coordination (3)	+ -
Analysis (1)	+ -
Chaos control (1)	+ -
Collinearity (1)	+ -
Coordinate Descent (1)	+ -

Coordinate Transformation (1)	+ -
Coordination (1)	+ -
Delay coordinate embedding (1)	+ -
Disturbance (1)	+ -
Drift (1)	+ -
Duffing oscillator (1)	+ -
Elastic Net (1)	+ -
Energy harvesting (1)	+ -
Feedback control (1)	+ -
GPS coordinate estimation (1)	+ -
High-Dimensional Data (1)	+ -
Implicit coordination (1)	+ -
Jitter (1)	+ -
Large-Scale Distributed System (1)	+ -
Lasso (1)	+ -
Least squares estimation (1)	+ -
Matchmaking (1)	+ -
Mental model quality (1)	+ -
Modular coordination (Architecture) (1)	+ -
Perceptions of sharedness (1)	+ -
Pointing Accuracy (1)	+ -
Pointing error (1)	+ -
Project management (1)	+ -
Remote Sensing (1)	+ -
Resource Allocation (1)	+ -

ETD Collection (15)	+ -
Honors Collection (2)	+ -

University of Central Florida (16)	+ -
Jentsch, Florian (2)	+ -
Jiang, James (2)	+ -
Salas, Eduardo (2)	+ -
Andrews, Diane (1)	+ -

Bai, Xin (1)	+ -
Bisbey, Tiffany (1)	+ -
Block, David T. (1)	+ -
Boloni, Ladislau (1)	+ -
Chapple, Reshawna (1)	+ -
Das, Tuhin (1)	+ -
Dejesus, Fanya (1)	+ -
Desiraju, Ramarao (1)	+ -
Engineering (1)	+ -
Fiore, Stephen (1)	+ -
Fisher, Kristina Childs (1)	+ -
Foroosh, Hassan (1)	+ -
Geiyer, Daniel (1)	+ -
Gryglewicz, Kimberley (1)	+ -
Hoeft, Raegan (1)	+ -
Hsu, Shih-Chieh (1)	+ -
Jacobson, Craig (1)	+ -
Jha, Sumit (1)	+ -
Junejo, Imran (1)	+ -
Kauffman, Jeffrey L. (1)	+ -
Laviers, Kennard (1)	+ -
Lawrence, Shawn (1)	+ -
Leonessa, Alexander (1)	+ -
Li, Yuzhu (1)	+ -
Maboudou, Edgard (1)	+ -

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