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(1 - 11 of 11)
- Title
- SOCIAL GROUPING BEHAVIORS OF CAPTIVE FEMALE HIPPOPOTAMUS AMPHIBIUS.
- Creator
-
Blowers, Tracy, Waterman, Jane, University of Central Florida
- Abstract / Description
-
Levels of sociality vary depending on the costs and benefits associated with grouping behavior. Grouping species form either ephemeral aggregations due to resource availability, or structured groups based on familiarity of individuals. Because there are different costs and benefits associated with different types of groups, it is important to understand more about group structure before making predictions about specific behaviors. Female Hippopotamus amphibius are known to aggregate in the...
Show moreLevels of sociality vary depending on the costs and benefits associated with grouping behavior. Grouping species form either ephemeral aggregations due to resource availability, or structured groups based on familiarity of individuals. Because there are different costs and benefits associated with different types of groups, it is important to understand more about group structure before making predictions about specific behaviors. Female Hippopotamus amphibius are known to aggregate in the wild but the true nature of their grouping behavior is still not understood. My objective was to determine if captive female hippos form either ephemeral aggregations or social groups. Behavioral data, using continuous focal animal sampling and scan sampling, were collected on a group of nine captive female hippos housed at Disney's Animal Kingdom® Theme Park. The behavioral data were used to analyze interactions between hippos, association patterns for kin and non-kin as well as familiarity, dominance hierarchy, and habitat preferences. My results support the hypothesis that hippos are forming social groups due to the attraction to particular individuals. There were more associations between kin than non-kin and also between individuals that have been together longer. Captive female hippos were also found to exhibit dominance patterns within the group. The results from this study may aid in the general understanding of hippopotamus behavior and aid in the captive management of hippos. Using my results as a starting point, research can begin looking at grouping patterns and its costs and benefits of sociality in wild hippopotamus populations.
Show less - Date Issued
- 2008
- Identifier
- CFE0002239, ucf:47905
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002239
- Title
- The Impact of Individual Perceptions of the Fairness of Public Affirmative Action Policy Statements on Attitudes toward the Organization.
- Creator
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Zaragoza, Joseph, Wooten, William, Carter, Nathan, Fritzsche, Barbara, University of Central Florida
- Abstract / Description
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The purpose of this research project was to explore differences in perceptions of organizational justice and related attitudes. Through the use of a 3 x 2 experimental design, participants were randomly assigned to groups in which they were exposed to a fictitious organization's mock recruitment document publicizing different types of affirmative action programs and varying levels of information regarding the mechanics of such programs. Results did not demonstrate statistically significant...
Show moreThe purpose of this research project was to explore differences in perceptions of organizational justice and related attitudes. Through the use of a 3 x 2 experimental design, participants were randomly assigned to groups in which they were exposed to a fictitious organization's mock recruitment document publicizing different types of affirmative action programs and varying levels of information regarding the mechanics of such programs. Results did not demonstrate statistically significant differences across groups. Project implications, limitations, and suggestions for future research are discussed.
Show less - Date Issued
- 2012
- Identifier
- CFE0004622, ucf:49938
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004622
- Title
- RIGHT-WING AUTHORITARIANISM, SOCIAL DOMINANCE ORIENTATION, AND WORKPLACE IMPLICATIONS.
- Creator
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Burnell, Devin S, Modianos, Doan T., University of Central Florida
- Abstract / Description
-
Workplace bullying is a recently recognized problem within organizations. Two personalities may be theoretically related, and may be able to predict this aggressive behavior: right-wing authoritarianism and social dominance orientation. However, it is still unclear how to measure right-wing authoritarianism as a construct. Two surveys were distributed. The first was to assess the factor structure inconsistency among the literature. A three-factor operationalization was supported. Analysis of...
Show moreWorkplace bullying is a recently recognized problem within organizations. Two personalities may be theoretically related, and may be able to predict this aggressive behavior: right-wing authoritarianism and social dominance orientation. However, it is still unclear how to measure right-wing authoritarianism as a construct. Two surveys were distributed. The first was to assess the factor structure inconsistency among the literature. A three-factor operationalization was supported. Analysis of the second survey examined the relationship between the aggression dimension of right-wing authoritarianism, dangerous worldview and workplace bullying; as well as the relationship between social dominance orientation and competitive worldview on workplace bullying. No significant relationship was found between authoritarian aggression and workplace bullying, however, social dominance orientation fully mediated competitive worldview and workplace bullying. Theoretical implications, limitations, and practical applications are discussed.
Show less - Date Issued
- 2016
- Identifier
- CFH2000015, ucf:45587
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000015
- Title
- AUTHORITARIANSIM AND COLLECTIVISM: ANTECEDENTS AND CONSEQUENCES AMONG COLLEGE STUDENTS.
- Creator
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Samuel, Jasmine, Modianos, Doan T., University of Central Florida
- Abstract / Description
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Moral Foundations Theory (MFT) suggests there are five distinct moral dimensions, which define morality as a whole. MFT can be broken down into two groups binding: in group/loyalty, authority/respect, and purity/sanctity-which encompass group morality. Harm/Care, fairness/reciprocity are individualizing dimensions, which highlight individual morality. Recent work has found MFT predicts sociopolitical ideologies, as well as sociopolitical attitudes. In an effort to better understand the...
Show moreMoral Foundations Theory (MFT) suggests there are five distinct moral dimensions, which define morality as a whole. MFT can be broken down into two groups binding: in group/loyalty, authority/respect, and purity/sanctity-which encompass group morality. Harm/Care, fairness/reciprocity are individualizing dimensions, which highlight individual morality. Recent work has found MFT predicts sociopolitical ideologies, as well as sociopolitical attitudes. In an effort to better understand the existing relationships we investigate MFT as a predictor of sociopolitical parties, and attitudes Right-Wing Authoritarianism (RWA) and Social Dominance Orientation (SDO). We also draw on similarities between Individualism/Collectivism and MFT. Specifically we demonstrate individualizing foundations, and dimensions of individualism predict SDO, where as Binding dimensions and dimensions of Collectivism relate to RWA.
Show less - Date Issued
- 2016
- Identifier
- CFH2000012, ucf:45600
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH2000012
- Title
- The Impact of Technology on Management Control: Degradation, Empowerment, or Technology Dominance?.
- Creator
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Canada, Joseph, Arnold, Vicky, Roberts, Robin, Sutton, Steven, Benford, Tanya, University of Central Florida
- Abstract / Description
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The evolution of technology brings with it the evolution of business processes. Without a doubt, technology changes how work is performed. At first glance, workplace technology appears to be a great boon to society. However, research presents opposing views on how workplace technologies impact the individual. One perspective argues that organizations utilize technology to redesign work processes, such that the worker requires less skill, autonomy, and compensation. The opposing perspective...
Show moreThe evolution of technology brings with it the evolution of business processes. Without a doubt, technology changes how work is performed. At first glance, workplace technology appears to be a great boon to society. However, research presents opposing views on how workplace technologies impact the individual. One perspective argues that organizations utilize technology to redesign work processes, such that the worker requires less skill, autonomy, and compensation. The opposing perspective argues that organizations utilize technology to empower employees to improve efficiency and profits. This dissertation consists of three interrelated studies examining workplace technology's impact on decision makers. The first study examines the capability of an enterprise system to increase the application of scientific management techniques to middle management and, consequently, to degrade middle management's work by limiting their autonomy. The second study investigates the capability of an enterprise system to facilitate the empowerment of managers via mutual monitoring and social identification. The third study builds upon the first study by examining how limiting autonomy through technology impacts the intrinsic motivation of decision makers and, as a result, affects the decision making process. Study one applies labor process theory to explain how enterprise systems can degrade the work of middle management via scientific management techniques. The purpose of this study is to test if the expectations of labor process theory can be applied to enterprise systems. In order to test this assertion, a field survey utilizing 189 middle managers is employed and the data is analyzed using component based structural equation modeling. The results indicate that enterprise system integration increases two scientific management techniques, formalization and performance measurement, but do not reveal a significant relationship between enterprise system integration and routinization. Interestingly, the results also indicate that routinization is the only scientific management technique, of the three studied, that directly limits the autonomy of the middle managers. Although performance measurement does not reduce autonomy directly, performance measurement interacts with routinization to reduce autonomy. This study contributes to the enterprise system literature by demonstrating enterprise systems' ability to increase the degree of scientific management applied to middle management. It also contributes to labor process theory by revealing that routinization may be the scientific management technique that determines whether other control techniques are utilized in a manner consistent with labor process theory. The ability of an enterprise system to facilitate the application of Mary Parker Follett's managerial control concepts are investigated in the second study. Specifically, Follett theorizes that information sharing facilitates the internalization of group goals and empowers individuals to have more influence and be more effective. This study employs a survey of 206 managers to test the theoretical relationships. The results indicate that enterprise system integration increases information sharing in the form of mutual monitoring, consequently, leading to social identification among peer managers. Additionally, social identification among peer managers empowers managers to have more influence over the organization. The study contributes to empowerment research by acknowledging and verifying the role that social identification plays in translating an empowering work climate into empowered managers. The study's conclusion that enterprise system integration facilitates the application of Follett's managerial control concepts extends both enterprise system and managerial control literature. The third study builds upon study one by examining the affect that autonomy has upon the decision maker. This study marries self-determination theory and technology dominance theory to understand the role that self-determination, intrinsic motivation, and engagement have upon technology dominance. Self-determination theory asserts that higher degrees of self-determination increase intrinsic motivation. Furthermore, self-determination research finds that intrinsic motivation increases engagement, while technology dominance research indicates that lack of engagement is an antecedent of technology dominance. Thus, applying self-determination theory as a predictor of technology dominance suggests that autonomy and relatedness associated with a task increase the intrinsic motivation to complete that task and consequently increase engagement in the task. Task engagement, in turn, reduces the likelihood of technology dominance. The proposed theoretical model is tested experimentally with 83 junior level business students. The results do not support the theoretical model, however the findings reveal that intrinsic motivation does reduce the likelihood of technology dominance. This indicates that intrinsic motivation as a predictor of technology dominance should be further investigated. Additionally, the study contributes to technology dominance literature by exhibiting a more appropriate operationalization of the inappropriate reliance aspect of technology dominance. This dissertation reveals that various theories concerning workplace technology and management control techniques have both validity and limitations. Labor process theorists cannot assume that all technologies and management control techniques are utilized to undermine the employee's value to the organization, as Study 2 reveals that enterprise systems and mutual monitoring lead to empowered managers. Likewise, proponents of enterprise systems cannot assume that the integrated nature of enterprise systems is always utilized in an empowering manner, as Study 1 reveals the increased performance measurement through enterprise systems can be utilized to limit managers in a routinized job environment. While the third study was unable to determine that the control features in technology affect the intrinsic motivation to complete a task, the findings do reveal that intrinsic motivation is directly related to technology dominance. The findings and theoretical refinements demonstrate that workplace technology and management control have a complicated relationship with the employee and that the various theories concerning them cannot be applied universally.
Show less - Date Issued
- 2013
- Identifier
- CFE0004980, ucf:49569
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004980
- Title
- Juvenile Ornamentation: Its Evolution, Genetic Basis, and Variation Across Habitats.
- Creator
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Tringali, Angela, Noss, Reed, Bowman, Reed, Fauth, John, Fedorka, Kenneth, University of Central Florida
- Abstract / Description
-
Ornamental traits are considered honest advertisements of fitness, and their evolution is usually explained in terms of sexual selection. This explanation remains unsatisfactory in some instances, for example, juvenile birds whose plumage is molted prior to adulthood and breeding. I first evaluate whether juvenile plumage reflectance signals dominance status in the Federally Threatened Florida scrub-jay (Aphelocoma coerulescens) using a combination of observational and experimental methods....
Show moreOrnamental traits are considered honest advertisements of fitness, and their evolution is usually explained in terms of sexual selection. This explanation remains unsatisfactory in some instances, for example, juvenile birds whose plumage is molted prior to adulthood and breeding. I first evaluate whether juvenile plumage reflectance signals dominance status in the Federally Threatened Florida scrub-jay (Aphelocoma coerulescens) using a combination of observational and experimental methods. Then I estimate the heritability, non-genetic maternal and environmental effects, and strength of selection on juvenile plumage reflectance using archived feather samples and a pedigree constructed from historical nest records. Finally, I compare plumage reflectance and its use as a signal between a wildland and suburban population of scrub-jays. I conclude that plumage reflectance is a signal of dominance, and that social selection can also drive the evolution of sexually dimorphic traits. In this species, plumage reflectance is heritable and influenced by maternal effects, but environmental effects are inconsequential. Although this trait appears to have an important function, only mean brightness and female hue are associated with lifetime reproductive success. Plumage reflectance was more UV-shifted in the suburban birds, but there is no reason to believe that urbanization decreases the value of this plumage as a signal. However, these plumage differences may facilitate dispersal from suburban areas, contributing to the decline of suburban populations.
Show less - Date Issued
- 2013
- Identifier
- CFE0005431, ucf:50413
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005431
- Title
- RESOURCE ALLOCATION SCHEMES AND PERFORMANCE EVALUATION MODELS FOR WAVELENGTH DIVISION MULTIPLEXED OPTICAL NETWORKS.
- Creator
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El Houmaidi, Mounire, Bassiouni, Mostafa, University of Central Florida
- Abstract / Description
-
Wavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in network infrastructure and next-generation Internet architectures. WDM networks have the potential to provide unprecedented bandwidth, reduce processing cost, achieve protocol transparency, and enable efficient failure handling. This dissertation addresses the important issues of improving the performance and enhancing the reliability of WDM networks as well as modeling and evaluating the...
Show moreWavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in network infrastructure and next-generation Internet architectures. WDM networks have the potential to provide unprecedented bandwidth, reduce processing cost, achieve protocol transparency, and enable efficient failure handling. This dissertation addresses the important issues of improving the performance and enhancing the reliability of WDM networks as well as modeling and evaluating the performance of these networks. Optical wavelength conversion is one of the emerging WDM enabling technologies that can significantly improve bandwidth utilization in optical networks. A new approach for the sparse placement of full wavelength converters based on the concept of the k-Dominating Set (k-DS) of a graph is presented. The k-DS approach is also extended to the case of limited conversion capability using three scalable and cost-effective switch designs: flexible node-sharing, strict node-sharing and static mapping. Compared to full search algorithms previously proposed in the literature, the K-DS approach has better blocking performance, has better time complexity and avoids the local minimum problem. The performance benefit of the K-DS approach is demonstrated by extensive simulation. Fiber delay line (FDL) is another emerging WDM technology that can be used to obtain limited optical buffering capability. A placement algorithm, k-WDS, for the sparse placement of FDLs at a set of selected nodes in Optical Burst Switching (OBS) networks is proposed. The algorithm can handle both uniform and non-uniform traffic patterns. Extensive performance tests have shown that k-WDS provides more efficient placement of optical fiber delay lines than the well-known approach of placing the resources at nodes with the highest experienced burst loss. Performance results that compare the benefit of using FDLs versus using optical wavelength converters (OWCs) are presented. A new algorithm, A-WDS, for the placement of an arbitrary numbers of FDLs and OWCs is introduced and is evaluated under different non-uniform traffic loads. This dissertation also introduces a new cost-effective optical switch design using FDL and a QoS-enhanced JET (just enough time) protocol suitable for optical burst switched WDM networks. The enhanced JET protocol allows classes of traffic to benefit from FDLs and OWCs while minimizing the end-to-end delay for high priority bursts. Performance evaluation models of WDM networks represent an important research area that has received increased attention. A new analytical model that captures link dependencies in all-optical WDM networks under uniform traffic is presented. The model enables the estimation of connection blocking probabilities more accurately than previously possible. The basic formula of the dependency between two links in this model reflects their degree of adjacency, the degree of connectivity of the nodes composing them and their carried traffic. The usefulness of the model is illustrated by applying it to the sparse wavelength converters placement problem in WDM networks. A lightpath containing converters is divided into smaller sub-paths such that each sub-path is a wavelength continuous path and the nodes shared between these sub-paths are full wavelength conversion capable. The blocking probability of the entire path is obtained by computing the blocking probabilities of the individual sub-paths. The analytical-based sparse placement algorithm is validated by comparing it with its simulation-based counterpart using a number of network topologies. Rapid recovery from failure and high levels of reliability are extremely important in WDM networks. A new Fault Tolerant Path Protection scheme, FTPP, for WDM mesh networks based on the alarming state of network nodes and links is introduced. The results of extensive simulation tests show that FTPP outperforms known path protection schemes in terms of loss of service ratio and network throughput. The simulation tests used a wide range of values for the load intensity, the failure arrival rate and the failure holding time. The FTPP scheme is next extended to the differentiated services model and its connection blocking performance is evaluated. Finally, a QoS-enhanced FTPP (QEFTPP) routing and path protection scheme in WDM networks is presented. QEFTPP uses preemption to minimize the connection blocking percentage for high priority traffic. Extensive simulation results have shown that QEFTPP achieves a clear QoS differentiation among the traffic classes and provides a good overall network performance.
Show less - Date Issued
- 2005
- Identifier
- CFE0000346, ucf:46291
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000346
- Title
- GLOBAL SECURE SETS OF TREES AND GRID-LIKE GRAPHS.
- Creator
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Ho, Yiuyu, Dutton, Ronald, University of Central Florida
- Abstract / Description
-
Let G = (V, E) be a graph and let S be a subset of vertices. The set S is a defensive alliance if for all x in S, |N intersect S| >= |N - S|. The concept of defensive alliances was introduced in , primarily for the modeling of nations in times of war, where allied nations are in mutual agreement to join forces if anyone of them is attacked. For a vertex x in a defensive alliance, the number of neighbors of x inside the alliance, plus the vertex x, is at least the number of neighbors of x...
Show moreLet G = (V, E) be a graph and let S be a subset of vertices. The set S is a defensive alliance if for all x in S, |N intersect S| >= |N - S|. The concept of defensive alliances was introduced in , primarily for the modeling of nations in times of war, where allied nations are in mutual agreement to join forces if anyone of them is attacked. For a vertex x in a defensive alliance, the number of neighbors of x inside the alliance, plus the vertex x, is at least the number of neighbors of x outside the alliance. In a graph model, the vertices of a graph represent nations and the edges represent country boundaries. Thus, if the nation corresponding to a vertex x is attacked by its neighbors outside the alliance, the attack can be thwarted by x with the assistance of its neighbors in the alliance. In a different subject matter, applies graph theory to model the world wide web, where vertices represent websites and edges represent links between websites. A web community is a subset of vertices of the web graph, such that every vertex in the community has at least as many neighbors in the set as it has outside. So, a web community C satisfies for all x in C, |N intersect C| > |N - C|. These sets are very similar to defensive alliances. They are known as strong defensive alliances in the literature of alliances in graphs. Other areas of application for alliances and related topics include classification, data clustering, ecology, business and social networks. Consider the application of modeling nations in times of war introduced in the first paragraph. In a defensive alliance, any attack on a single member of the alliance can be successfully defended. However, as will be demonstrated in Chapter 1, a defensive alliance may not be able to properly defend itself when multiple members are under attack at the same time. The concept of secure sets is introduced in for exactly this purpose. The set S is a secure set if every subset X of S, with the assistance of vertices in S, can successfully defend against simultaneous attacks coming from vertices outside of S. The exact definition of simultaneous attacks and how such attacks may be defended will be provided in Chapter 1. In , the authors presented an interesting characterization for secure sets which resembles the definition of defensive alliances. A non-empty set S is a secure set if and only if for all subset X of S, |N intersect S| >= |N - S| (, Theorem 11). The cardinality of a minimum secure set is the security number of G, denoted s(G). A secure set S is a global secure set if it further satisfies N = V. The cardinality of a minimum global secure set of G is the global security number of G, denoted gs(G). In this work, we present results on secure sets and global secure sets. In particular, we present algorithms and bounds for the global security numbers of trees, and the exact values of the global security numbers of paths, cycles and their Cartesian products. Petter Kristiansen, Sandra M. Hedetniemi, and Stephen T. Hedetniemi. "Alliances in graphs." J. Combin. Math. Combin. Comput., 48:157-177, 2004. G. W. Flake, S. Lawrence, and C. L. Giles. "Efficient identification of web communities." ACM SIGKDD, pp. 150-160, 2000. Robert C. Brigham, Ronald D. Dutton, and Stephen T. Hedetniemi. "Security in graphs." Discrete Appl. Math., 155(13):1708-1714, 2007.
Show less - Date Issued
- 2011
- Identifier
- CFE0003888, ucf:48719
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003888
- Title
- Crimean Rhetorical Sovereignty: Resisting a Deportation of Identity.
- Creator
-
Berry, Christian, Pigg, Stacey, Zemlyanskiy, Pavlo, Rounsaville, Angela, University of Central Florida
- Abstract / Description
-
On a small contested part of the world, the peninsula of Crimea, once a part of the former Soviet Union, lives a people who have endured genocide and who have struggled to etch out an identity in a land once their own. They are the Crimean Tatar. Even their name, an exonym promoting the Crimeans' (")peripheral status(") (Powell) and their ensuing (")cultural schizophrenia(") (Vizenor), bears witness to the otherization they have withstood throughout centuries. However, despite attempts to...
Show moreOn a small contested part of the world, the peninsula of Crimea, once a part of the former Soviet Union, lives a people who have endured genocide and who have struggled to etch out an identity in a land once their own. They are the Crimean Tatar. Even their name, an exonym promoting the Crimeans' (")peripheral status(") (Powell) and their ensuing (")cultural schizophrenia(") (Vizenor), bears witness to the otherization they have withstood throughout centuries. However, despite attempts to relegate them to the history books, Crimeans are alive and well in the (")motherland,(") but not without some difficulty. Having been forced to reframe their identities because of numerous imperialistic, colonialist, and soviet behavior and policies, there have been many who have resisted, first and foremost through rhetorical sovereignty, the ability to reframe Crimean Tatar identity through Crimean Tatar rhetoric. This negotiation of identity through rhetoric has included a fierce defense of their language and culture in what Malea Powell calls a (")war with homogeneity,(") a struggle for identification based on resistance. This thesis seeks to understand the rhetorical function of naming practices as acts that inscribe material meaning and perform marginalization or resistance within the context of Crimea-L, a Yahoo! Group listserv as well as immediate and remote Crimean history. To analyze the rhetoric of marginalization and resistance in naming practices, I use the Discourse Historical Approach (DHA) to Critical Discourse Analysis (CDA) within recently archived discourses. Ruth Wodak's DHA strategies will be reappropriated as Naming Practice Strategies, depicting efforts in otherization or rhetorical sovereignty.
Show less - Date Issued
- 2013
- Identifier
- CFE0004816, ucf:49749
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004816
- Title
- Optimal distribution network reconfiguration using meta-heuristic algorithms.
- Creator
-
Asrari, Arash, Wu, Thomas, Lotfifard, Saeed, Haralambous, Michael, Atia, George, Pazour, Jennifer, University of Central Florida
- Abstract / Description
-
Finding optimal configuration of power distribution systems topology is an NP-hard combinatorial optimization problem. It becomes more complex when time varying nature of loads in large-scale distribution systems is taken into account. In the second chapter of this dissertation, a systematic approach is proposed to tackle the computational burden of the procedure. To solve the optimization problem, a novel adaptive fuzzy based parallel genetic algorithm (GA) is proposed that employs the...
Show moreFinding optimal configuration of power distribution systems topology is an NP-hard combinatorial optimization problem. It becomes more complex when time varying nature of loads in large-scale distribution systems is taken into account. In the second chapter of this dissertation, a systematic approach is proposed to tackle the computational burden of the procedure. To solve the optimization problem, a novel adaptive fuzzy based parallel genetic algorithm (GA) is proposed that employs the concept of parallel computing in identifying the optimal configuration of the network. The integration of fuzzy logic into GA enhances the efficiency of the parallel GA by adaptively modifying the migration rates between different processors during the optimization process. A computationally efficient graph encoding method based on Dandelion coding strategy is developed which automatically generates radial topologies and prevents the construction of infeasible radial networks during the optimization process. The main shortcoming of the proposed algorithm in Chapter 2 is that it identifies only one single solution. It means that the system operator will not have any option but relying on the found solution. That is why a novel hybrid optimization algorithm is proposed in the third chapter of this dissertation that determines Pareto frontiers, as candidate solutions, for multi-objective distribution network reconfiguration problem. Implementing this model, the system operator will have more flexibility in choosing the best configuration among the alternative solutions. The proposed hybrid optimization algorithm combines the concept of fuzzy Pareto dominance (FPD) with shuffled frog leaping algorithm (SFLA) to recognize non-dominated suboptimal solutions identified by SFLA. The local search step of SFLA is also customized for power systems applications so that it automatically creates and analyzes only the feasible and radial configurations in its optimization procedure which significantly increases the convergence speed of the algorithm. In the fourth chapter, the problem of optimal network reconfiguration is solved for the case in which the system operator is going to employ an optimization algorithm that is automatically modifying its parameters during the optimization process. Defining three fuzzy functions, the probability of crossover and mutation will be adaptively tuned as the algorithm proceeds and the premature convergence will be avoided while the convergence speed of identifying the optimal configuration will not decrease. This modified genetic algorithm is considered a step towards making the parallel GA, presented in the second chapter of this dissertation, more robust in avoiding from getting stuck in local optimums. In the fifth chapter, the concentration will be on finding a potential smart grid solution to more high-quality suboptimal configurations of distribution networks. This chapter is considered an improvement for the third chapter of this dissertation for two reasons: (1) A fuzzy logic is used in the partitioning step of SFLA to improve the proposed optimization algorithm and to yield more accurate classification of frogs. (2) The problem of system reconfiguration is solved considering the presence of distributed generation (DG) units in the network. In order to study the new paradigm of integrating smart grids into power systems, it will be analyzed how the quality of suboptimal solutions can be affected when DG units are continuously added to the distribution network.The heuristic optimization algorithm which is proposed in Chapter 3 and is improved in Chapter 5 is implemented on a smaller case study in Chapter 6 to demonstrate that the identified solution through the optimization process is the same with the optimal solution found by an exhaustive search.
Show less - Date Issued
- 2015
- Identifier
- CFE0005575, ucf:50238
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005575
- Title
- Chlamydia trachomatis Transformants Show a Significant Reduction in Rates of Invasion upon Removal of Key Tarp Domains.
- Creator
-
Parrett, Christopher, Jewett, Travis, Roy, Herve, Moore, Sean, University of Central Florida
- Abstract / Description
-
Chlamydia trachomatis is an obligate, intracellular bacterium which is known to cause multiple human infections including nongonococcal urethritis (serovars D-K), lymphogranuloma venereum (serovars L1, L2, L3) and trachoma (serovars A-C). The infectious form of the bacterium, called the elementary body (EB), harbors a type III secreted effector known as Tarp (translocated actin recruiting phosphoprotein) which is a candidate virulence factor and is hypothesized to play a role in C....
Show moreChlamydia trachomatis is an obligate, intracellular bacterium which is known to cause multiple human infections including nongonococcal urethritis (serovars D-K), lymphogranuloma venereum (serovars L1, L2, L3) and trachoma (serovars A-C). The infectious form of the bacterium, called the elementary body (EB), harbors a type III secreted effector known as Tarp (translocated actin recruiting phosphoprotein) which is a candidate virulence factor and is hypothesized to play a role in C. trachomatis' ability to invade and grow within epithelial cells in a human host. C. trachomatis L2 Tarp harbors five unique protein domains which include the Phosphorylation Domain, the Proline Rich Domain, the Actin Binding Domain, and two F-Actin Binding Domains. Tarp has been biochemically characterized in vitro, but it has yet to be characterized in vivo due to a lack of genetic tools in C. trachomatis. Through the recent generation of a chlamydial transformation system, we have created transformants which express epitope tagged wild type or mutant Tarp effectors. In this thesis, C. trachomatis transformants expressing Tarp lacking one of the five biochemically defined protein domains were used to examine both bacterial invasion and bacterial development within mammalian host cells. Our results demonstrate that those EBs which harbor mutant Tarp missing either its Phosphorylation Domain or its Actin Binding Domain were less capable of host cell invasion. However, these transformants, once internalized, were capable of normal development when compared to wild type C. trachomatis or C. trachomatis harboring an epitope tagged wild type Tarp effector. These results suggest that transformant expressed Tarp lacking the Phosphorylation Domain or Actin Binding Domain may be acting as a dominant-negative effector protein. Ultimately, these results support the hypothesis that Tarp is a virulence factor for Chlamydia trachomatis. Furthermore, this data indicates that through the manipulation of the Tarp effector, C. trachomatis pathogenesis may be attenuated.
Show less - Date Issued
- 2016
- Identifier
- CFE0006159, ucf:51142
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006159
