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Title: COALITION FORMATION IN MULTI-AGENT UAV SYSTEMS.
Creator: DeJong, Paul, Boloni, Ladislau, University of Central Florida
Abstract / Description: Coalitions are collections of agents that join together to solve a common problem that either cannot be solved individually or can be solved more efficiently as a group. Each individual agent has capabilities that can benefit the group when working together as a coalition. Typically, individual capabilities are joined together in an additive way when forming a coalition. This work will introduce a new operator that is used when combining capabilities, and suggest that the behavior of the...
Show moreCoalitions are collections of agents that join together to solve a common problem that either cannot be solved individually or can be solved more efficiently as a group. Each individual agent has capabilities that can benefit the group when working together as a coalition. Typically, individual capabilities are joined together in an additive way when forming a coalition. This work will introduce a new operator that is used when combining capabilities, and suggest that the behavior of the operator is contextual, depending on the nature of the capability itself. This work considers six different capabilities of Unmanned Air Vehicles (UAV) and determines the nature of the new operator in the context of each capability as coalitions (squadrons) of UAVs are formed. Coalitions are formed using three different search algorithms, both with and without heuristics: Depth-First, Depth-First Iterative Deepening, and Genetic Algorithm (GA). The effectiveness of each algorithm is evaluated. Multi agent-based UAV simulation software was developed and used to test the ideas presented. In addition to coalition formation, the software aims to address additional multi-agent issues such as agent identity, mutability, and communication as applied to UAV systems, in a realistic simulated environment. Social potential fields provide a means of modeling a clustering attractive force at the same time as a collision-avoiding repulsive force, and are used by the simulation to maintain aircraft position relative to other UAVs.
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Date Issued: 2005
Identifier: CFE0000394, ucf:46332
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000394

Title: IDENTIFICATION AND SUITABILITY OF A NON-ANTHROPOMORPHIC META-LANGUAGE FRAMEWORK IN MILITARY APPLICATIONS.
Creator: Cardona, Gilbert, Proctor, Michael, University of Central Florida
Abstract / Description: Humans carry mental models concerning the behaviors, looks, and operation of products, tools, and items used in their daily lives. When these items do not fit a user's conceptual model confusion and inefficiency occur. There are four basic types of mental models based on interactive activities: 1) instructing, 2) conversing, 3) manipulating and navigating, and 4) exploring and browsing. This thesis will focus on the conversing conceptual model and its application to communications between...
Show moreHumans carry mental models concerning the behaviors, looks, and operation of products, tools, and items used in their daily lives. When these items do not fit a user's conceptual model confusion and inefficiency occur. There are four basic types of mental models based on interactive activities: 1) instructing, 2) conversing, 3) manipulating and navigating, and 4) exploring and browsing. This thesis will focus on the conversing conceptual model and its application to communications between human-agent teams to best fit a user's mental model for that communication. A non-anthropomorphic framework does not exist for use in military applications such as; target detection, nuclear, biological, and chemical agent detection, and explosive ordinance disposal. As agents become increasingly autonomous and complex in the currently military working environment an effective and un-confusing non-anthropomorphic meta-language framework must be explored and developed to fulfill the need for human-agent communications. The meta-language framework may consist of visual and audio cues as pose, motion, color, and non-speech sounds. This thesis will attempt to identify and evaluate a non-anthropomorphic framework of communications between human-human, human-agents, and agent-agent teams that will maximize the effectiveness of the communications in terms of efficiency and interpretation.
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Date Issued: 2007
Identifier: CFE0001687, ucf:47216
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001687

Title: A Framework For Workforce Management An Agent Based Simulation Approach.
Creator: Marin, Mario, Rabelo, Luis, Lee, Gene, Elshennawy, Ahmad, Kincaid, John, University of Central Florida
Abstract / Description: In today's advanced technology world, enterprises are in a constant state of competition. As the intensity of competition increases the need to continuously improve organizational performance has never been greater. Managers at all levels must be on a constant quest for finding ways to maximize their enterprises' strategic resources. Enterprises can develop sustained competitiveness only if their activities create value in unique ways. There should be an emphasis to transfer this...
Show moreIn today's advanced technology world, enterprises are in a constant state of competition. As the intensity of competition increases the need to continuously improve organizational performance has never been greater. Managers at all levels must be on a constant quest for finding ways to maximize their enterprises' strategic resources. Enterprises can develop sustained competitiveness only if their activities create value in unique ways. There should be an emphasis to transfer this competitiveness to the resources it has on hand and the resources it can develop to be used in this environment. The significance of human capital is even greater now, as the intangible value and the tacit knowledge of enterprises' resources should be strategically managed to achieve a greater level of continuous organizational success. This research effort seeks to provide managers with means for accurate decision making for their workforce management. A framework for modeling and managing human capital to achieve effective workforce planning strategies is built to assist enterprise in their long term strategic organizational goals.
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Date Issued: 2014
Identifier: CFE0005375, ucf:50439
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005375

Title: Quantitative Framework For Social Cultural Interactions.
Creator: Bhatia, Taranjeet, Boloni, Ladislau, Turgut, Damla, Sukthankar, Gita, Fiore, Stephen, University of Central Florida
Abstract / Description: For an autonomous robot or software agent to participate in the social life of humans, it must have a way to perform a calculus of social behavior. Such a calculus must have explanatory power (it must provide a coherent theory for why the humans act the way they do), and predictive power (it must provide some plausible events from the predicted future actions of the humans).This dissertation describes a series of contributions that would allow agents observing or interacting with humans to...
Show moreFor an autonomous robot or software agent to participate in the social life of humans, it must have a way to perform a calculus of social behavior. Such a calculus must have explanatory power (it must provide a coherent theory for why the humans act the way they do), and predictive power (it must provide some plausible events from the predicted future actions of the humans).This dissertation describes a series of contributions that would allow agents observing or interacting with humans to perform a calculus of social behavior taking into account cultural conventions and socially acceptable behavior models. We discuss the formal components of the model: culture-sanctioned social metrics (CSSMs), concrete beliefs (CBs) and action impact functions. Through a detailed case study of a crooked seller who relies on the manipulation of public perception, we show that the model explains how the exploitation of social conventions allows the seller to finalize transactions, despite the fact that the clients know that they are being cheated. In a separate study, we show that how the crooked seller can find an optimal strategy with the use of reinforcement learning.We extend the CSSM model for modeling the propagation of public perception across multiple social interactions. We model the evolution of the public perception both over a single interaction and during a series of interactions over an extended period of time. An important aspect for modeling the public perception is its propagation - how the propagation is affected by the spatio-temporal context of the interaction and how does the short-term and long-term memory of humans affect the overall public perception.We validated the CSSM model through a user study in which participants cognizant with the modeled culture had to evaluate the impact on the social values. The scenarios used in the experiments modeled emotionally charged social situations in a cross-cultural setting and with the presence of a robot. The scenarios model conflicts of cross-cultural communication as well as ethical, social and financial choices. This study allowed us to study whether people sharing the same culture evaluate CSSMs at the same way (the inter-cultural uniformity conjecture). By presenting a wide range of possible metrics, the study also allowed us to determine whether any given metric can be considered a CSSM in a given culture or not.
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Date Issued: 2016
Identifier: CFE0006262, ucf:51047
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006262

Title: Planning and Control of Swarm Motion as Continua.
Creator: Rastgoftar, Hossein, Jayasuriya, Suhada, Das, Tuhin, Xu, Chengying, Qu, Zhihua, Simaan, Marwan, University of Central Florida
Abstract / Description: In this thesis, new algorithms for formation control of multi agent systems (MAS) based on continuum mechanics principles will be investigated. For this purpose agents of the MAS are treated as particles in a continuum, evolving in an n-D space, whose desired configuration is required to satisfy an admissible deformation function. Considered is a specific class of mappings that is called homogenous where the Jacobian of the mapping is only a function of time and is not spatially varying. The...
Show moreIn this thesis, new algorithms for formation control of multi agent systems (MAS) based on continuum mechanics principles will be investigated. For this purpose agents of the MAS are treated as particles in a continuum, evolving in an n-D space, whose desired configuration is required to satisfy an admissible deformation function. Considered is a specific class of mappings that is called homogenous where the Jacobian of the mapping is only a function of time and is not spatially varying. The primary objectives of this thesis are to develop the necessary theory and its validation via simulation on a mobile-agent based swarm test bed that includes two primary tasks: 1) homogenous transformation of MAS and 2) deployment of a random distribution of agents on to a desired configuration. Developed will be a framework based on homogenous transformations for the evolution of a MAS in an n-D space (n=1, 2, and 3), under two scenarios: 1) no inter-agent communication (predefined motion plan); and 2) local inter-agent communication. Additionally, homogenous transformations based on communication protocols will be used to deploy an arbitrary distribution of a MAS on to a desired curve. Homogenous transformation with no communication: A homogenous transformation of a MAS, evolving in an R^n space, under zero inter agent communication is first considered. Here the homogenous mapping, is characterized by an n x n Jacobian matrix Q(t) and an n x 1 rigid body displacement vector D(t), that are based on positions of n+1 agents of the MAS, called leader agents. The designed Jacobian Q(t) and rigid body displacement vector D(t) are passed onto rest of the agents of the MAS, called followers, who will then use that information to update their positions under a pre-defined motion plan. Consequently, the motion of MAS will evolve as a homogenous transformation of the initial configuration without explicit communication among agents. Homogenous Transformation under Local Communication: We develop a framework for homogenous transformation of MAS, evolving in R^n, under a local inter agent communication topology. Here we assume that some agents are the leaders, that are transformed homogenously in an n-D space. In addition, every follower agent of the MAS communicates with some local agents to update its position, in order to grasp the homogenous mapping that is prescribed by the leader agents. We show that some distance ratios that are assigned based on initial formation, if preserved, lead to asymptotic convergence of the initial formation to a final formation under a homogenous mapping.Deployment of a Random Distribution on a Desired Manifold: Deployment of agents of a MAS, moving in a plane, on to a desired curve, is a task that is considered as an application of the proposed approach. In particular, a 2-D MAS evolution problem is considered as two 1-D MAS evolution problems, where x or y coordinates of the position of all agents are modeled as points confined to move on a straight line. Then, for every coordinate of MAS evolution, bulk motion is controlled by two agents considered leaders that move independently, with rest of the follower agents motions evolving through each follower agent communicating with two adjacent agents.
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Date Issued: 2013
Identifier: CFE0004915, ucf:49640
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004915

Title: COALITION FORMATION AND TEAMWORK IN EMBODIED AGENTS.
Creator: Khan, Majid, Blni, Ladislau, University of Central Florida
Abstract / Description: Embodied agents are agents acting in the physical world, such as persons, robots, unmanned air or ground vehicles and so on. These types of agents are subject to spatio-temporal constraints, which do not exist for agents acting in a virtual environment. The movement of embodied agents is limited by obstacles and maximum velocity, while their communication is limited by the transmission range of their wireless devices. This dissertation presents contributions to the techniques of coalition...
Show moreEmbodied agents are agents acting in the physical world, such as persons, robots, unmanned air or ground vehicles and so on. These types of agents are subject to spatio-temporal constraints, which do not exist for agents acting in a virtual environment. The movement of embodied agents is limited by obstacles and maximum velocity, while their communication is limited by the transmission range of their wireless devices. This dissertation presents contributions to the techniques of coalition formation and teamwork coordination for embodied agents. We considered embodied agents in three different settings, each of them representative of a class of practical applications. First, we study coalition formation in the one dimensional world of vehicles driving on a highway. We assume that vehicles can communicate over short distances and carry agents which can advise the driver on convoy formation decisions. We introduce techniques which allow vehicles to influence the speed of the convoys, and show that this yields convoys which have a higher utility for the participating vehicles. Second, we address the problem of coalition formation in the two dimensional world. The application we consider is a disaster response scenario. The agents are forming coalitions through a multi-issue negotiation with spatio-temporal components where the coalitions maintain a set of commitments towards participating agents. Finally, we discuss a scenario where embodied agents form coalitions to optimally address dynamic, non-deterministic, spatio-temporal tasks. The application we consider is firefighters acting in a disaster struck city.
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Date Issued: 2007
Identifier: CFE0001843, ucf:47334
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001843

Title: THE EFFECTS OF ZINC NANOFERTILIZERS ON TOMATO PLANTS.
Creator: Pierre, Ketsira, Santra, Swadeshmukul, University of Central Florida
Abstract / Description: Farmers around the world aim to use soil with adequate nutrients to produce sufficient and quality crops to the world's ever-growing population. Unbalanced use of nutrients in the soil will lead to soil deficiency, which is usually seen in South and Southeast Asian countries. This soil deficiency is often due to loss of micronutrient(s) within the soil from farming practices. Micronutrient deficiency affects not only plant growth but human health. Plants grown in nutrient deficient soil...
Show moreFarmers around the world aim to use soil with adequate nutrients to produce sufficient and quality crops to the world's ever-growing population. Unbalanced use of nutrients in the soil will lead to soil deficiency, which is usually seen in South and Southeast Asian countries. This soil deficiency is often due to loss of micronutrient(s) within the soil from farming practices. Micronutrient deficiency affects not only plant growth but human health. Plants grown in nutrient deficient soil produce food with nutrient deficiencies, which affect people dependent on these foods for nutrients (Kathmandu, 2004). Nutrient deficient diseases and disorders like malnutrition are often seen in such cases. Current farming practices often involve leaching, mineralization, and bioconversion, which result in 50-70% loss of micronutrients. Smart practices from nanotechnology can lead conventional farming to more sustainable agriculture (Chhippa, 2016). This study aims to improve the dispersibility and uptake of zinc in plants different dual combination of ‘green' capping agents in zinc nanoparticles. The results of this study suggest tomato plants treated with urea coated with 3% Zn (w/w) using NAC-SAL ZnO showed a higher number of leaves and number of fruits set compared to controls.
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Date Issued: 2019
Identifier: CFH2000566, ucf:45665
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH2000566

Title: GOLD (III) MACROCYCLES ARE DNA INTERCALATORS THAT INHIBIT TOPOISOMERASE I AND II.
Creator: Fagenson, Alexander, Muller, Mark, University of Central Florida
Abstract / Description: Human Topoisomerase IB (TOP1) and Topoisomerase IIα (TOP2α) are essential nuclear enzymes that control DNA topology during DNA replication, gene transcription and cell division. These enzymes carry out their catalytic function by making transient single-strand (type I) or double-strand (type II) breaks in the DNA. In vivo, these complexes are short-lived but can be exploited by anti-cancer drugs to mechanistically kill cancer cells. Two general classes of compounds can kill cancer cells...
Show moreHuman Topoisomerase IB (TOP1) and Topoisomerase IIα (TOP2α) are essential nuclear enzymes that control DNA topology during DNA replication, gene transcription and cell division. These enzymes carry out their catalytic function by making transient single-strand (type I) or double-strand (type II) breaks in the DNA. In vivo, these complexes are short-lived but can be exploited by anti-cancer drugs to mechanistically kill cancer cells. Two general classes of compounds can kill cancer cells through a topo-targeted mechanism. Interfacial Poisons (IFPs) act at the enzyme-DNA interface to inhibit the religation reaction, resulting in the accumulation of DNA double-stand breaks (DSBs) in the genomic setting. Catalytic Inhibitor Compounds (CICs) act by interfering with other steps of the catalytic cycles such as DNA/protein binding or the cleavage reaction. In this work we identify new Au3+ macrocyclic gold complexes that act as CICs of both TOP1 and TOP2α. The complexes exhibit square planar geometry with an aromatic system that allows for DNA intercalation with binding affinities in the low micromolar range. A cytotoxicity screen across 60 human cancer cell lines performed by the National Cancer Institute (NCI, USA) reveals significant anti-tumor potential. Our lead compound (butyl gold(III) macrocycle, cmpd 3.) is currently undergoing further studies in animal models at the NCI. In vitro assays with purified DNA and enzyme reveal the Au3+ ion to be the quintessential switch that allows for DNA intercalation and subsequent inhibition of TOP1 and TOP2α.
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Date Issued: 2012
Identifier: CFH0004161, ucf:44823
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0004161

Title: Transparency and Communication Patterns in Human-Robot Teaming.
Creator: Lakhmani, Shan, Barber, Daniel, Jentsch, Florian, Reinerman, Lauren, Guznov, Svyatoslav, University of Central Florida
Abstract / Description: In anticipation of the complex, dynamic battlefields of the future, military operations are increasingly demanding robots with increased autonomous capabilities to support soldiers. Effective communication is necessary to establish a common ground on which human-robot teamwork can be established across the continuum of military operations. However, the types and format of communication for mixed-initiative collaboration is still not fully understood. This study explores two approaches to...
Show moreIn anticipation of the complex, dynamic battlefields of the future, military operations are increasingly demanding robots with increased autonomous capabilities to support soldiers. Effective communication is necessary to establish a common ground on which human-robot teamwork can be established across the continuum of military operations. However, the types and format of communication for mixed-initiative collaboration is still not fully understood. This study explores two approaches to communication in human-robot interaction, transparency and communication pattern, and examines how manipulating these elements with a robot teammate affects its human counterpart in a collaborative exercise. Participants were coupled with a computer-simulated robot to perform a cordon-and-search-like task. A human-robot interface provided different transparency types(-)about the robot's decision making process alone, or about the robot's decision making process and its prediction of the human teammate's decision making process(-)and different communication patterns(-)either conveying information to the participant or both conveying information to and soliciting information from the participant. This experiment revealed that participants found robots that both conveyed and solicited information to be more animate, likeable, and intelligent than their less interactive counterparts, but working with those robots led to more misses in a target classification task. Furthermore, the act of responding to the robot led to a reduction in the number of correct identifications made, but only when the robot was solely providing information about its own decision making process. Findings from this effort inform the design of next-generation visual displays supporting human-robot teaming.
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Date Issued: 2019
Identifier: CFE0007481, ucf:52674
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0007481

Title: A CONTEXTUAL APPROACH TO LEARNING COLLABORATIVE BEHAVIOR VIA OBSERVATION.
Creator: Johnson, Cynthia, Gonzalez, Avelino, University of Central Florida
Abstract / Description: This dissertation describes a novel technique to creating a simulated team of agents through observation. Simulated human teamwork can be used for a number of purposes, such as expert examples, automated teammates for training purposes and realistic opponents in games and training simulation. Current teamwork simulations require the team member behaviors be programmed into the simulation, often requiring a great deal of time and effort. None are able to observe a team at work and replicate...
Show moreThis dissertation describes a novel technique to creating a simulated team of agents through observation. Simulated human teamwork can be used for a number of purposes, such as expert examples, automated teammates for training purposes and realistic opponents in games and training simulation. Current teamwork simulations require the team member behaviors be programmed into the simulation, often requiring a great deal of time and effort. None are able to observe a team at work and replicate the teamwork behaviors. Machine learning techniques for learning by observation and learning by demonstration have proven successful at observing behavior of humans or other software agents and creating a behavior function for a single agent. The research described here combines current research in teamwork simulations and learning by observation to effectively train a multi-agent system in effective team behavior. The dissertation describes the background and work by others as well as a detailed description of the learning method. A prototype built to evaluate the developed approach as well as the extensive experimentation conducted is also described.
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Date Issued: 2011
Identifier: CFE0003602, ucf:48869
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003602

Title: COMPETITIVE ACTIONS OF NEW TECHNOLOGY FIRMS: THE RED QUEEN EFFECT AND NEW FIRM PERFORMANCE.
Creator: Porter, Robert, Ford, Cameron, University of Central Florida
Abstract / Description: The competitive strategy used by a new firm may be the most important strategy it ever employs (Covin & Slevin, 1989; Ferrier, 2001). A well-chosen and executed firm strategy is essential for a firm to realize its potential competitive advantage (Porter, 1981). A firmÃ‚Â's strategic intent and resulting competitive actions are especially important when firms are new and vulnerable as they strive to learn which strategic actions help them adapt to their rivals actions and...
Show moreThe competitive strategy used by a new firm may be the most important strategy it ever employs (Covin & Slevin, 1989; Ferrier, 2001). A well-chosen and executed firm strategy is essential for a firm to realize its potential competitive advantage (Porter, 1981). A firmÃ‚Â's strategic intent and resulting competitive actions are especially important when firms are new and vulnerable as they strive to learn which strategic actions help them adapt to their rivals actions and to their environment (Stinchcombe, 1965). Further, the competitive actions that new firms choose to take with rival firms affects the overall competitive dynamics of their industry (Smith, Ferrier, and Ndofor, 2001). One way to explore how the competitive actions of new firms affect their future is to capture and examine their individual competitive moves and countermoves over time (Smith, Grimm, Gannon, & Chen, 1991). Red Queen competition is a particular form of competitive dynamics that is well-suited to explore these issues of new rival firms (Barnett, 2008). Barnett and Sorenson (2002) suggested that competition and learning reinforce one another as organizations develop, and this is what van Valen (1973) referred to as the Ã‚Â'Red Queen.Ã‚Â' This definition of the Red Queen led to the development of the concept of Red Queen competition and the Red Queen effect. The competitive strategies these new firms use to obtain resources as they adapt, in particular how these firms compete and or cooperate, are key competitive strategies that remain understudied to-date (Amit, Glosten, and Muller, 1990). I explore Red Queen competition, and the ensuing Red Queen Effect, in a complex environmental setting that represents a high technology ecosystem (Arned, 1996, 2010; Iansiti & Levien, 2004a, 2004b; Moore, 1993; Pierce, 2009). New firms in such an ecosystem represent a particularly salient combination of type of firm, firm lifecycle period, and firm environment to examine strategic actions since these firms comprise a significant portion of the high-growth and future of our global economy (Stangler, 2010). Further, due to their need to rapidly adapt in a complex ecosystem, these firms rely heavily on short-lived information resources for competitive advantage (Barney, 1991; Nelson and Winter, 1982; Omerzel, 2008). To place this research in context, I consider the moderating effects of key environmental ecosystem resource conditions (Dess & Beard, 1984; Miller & Friesen, 1983; Sharfman & Dean, 1991). Empirical studies to-date have yielded mixed results and left unanswered questions about the basic components and the effects of Red Queen competition. To address these issues I explore this literature in chapter one of the dissertation, and in chapter two I develop a theoretical model of Red Queen competition that draws on the available empirical and theoretical literature to-date. Due to the mixed finding from the empirical results, I develop a precise agent-based simulation model of Red Queen competition in chapter three to facilitate data collection. Using this data I test a series of hypotheses designed to explore the fundamentals of Red Queen competition, specifically how escalating competitive activity for resources among new firms impacts their survival and performance. In addition, the moderating effect of environmental changes on Red Queen competition is also tested to explore the affect of context on Red Queen competition. Chapter four explains the findings from these hypotheses, future research directions, implications and limitations from the research, and my concluding thoughts.
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Date Issued: 2010
Identifier: CFE0003452, ucf:48389
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003452

Title: SPATIO-TEMPORAL NEGOTIATION PROTOCOLS.
Creator: Luo, Yi, Boloni, Ladislau, University of Central Florida
Abstract / Description: Canonical problems are simplified representations of a class of real world problems. They allow researchers to compare algorithms in a standard setting which captures the most important challenges of the real world problems being modeled. In this dissertation, we focus on negotiating a collaboration in space and time, a problem with many important real world applications. Although technically a multi-issue negotiation, we show that the problem can not be represented in a satisfactory manner...
Show moreCanonical problems are simplified representations of a class of real world problems. They allow researchers to compare algorithms in a standard setting which captures the most important challenges of the real world problems being modeled. In this dissertation, we focus on negotiating a collaboration in space and time, a problem with many important real world applications. Although technically a multi-issue negotiation, we show that the problem can not be represented in a satisfactory manner by previous models. We propose the "Children in the Rectangular Forest" (CRF) model as a possible canonical problem for negotiating spatio-temporal collaboration. In the CRF problem, two embodied agents are negotiating the synchronization of their movement for a portion of the path from their respective sources to destinations. The negotiation setting is zero initial knowledge and it happens in physical time. As equilibrium strategies are not practically possible, we are interested in strategies with bounded rationality, which achieve good erformance in a wide range of practical negotiation scenarios. We design a number of negotiation protocols to allow agents to exchange their offers. The simple negotiation protocol can be enhanced by schemes in which the agents add additional information of the negotiation flow to aid the negotiation partner in offer formation. Naturally, the performance of a strategy is dependent on the strategy of the opponent and the characteristics of the scenario. Thus we develop a set of metrics for the negotiation scenario which formalizes our intuition of collaborative scenarios (where the agents' interests are closely aligned) versus competitive scenarios (where the gain of the utility for one agent is paid off with a loss of utility for the other agent). Finally, we further investigate the sophisticated strategies which allow agents to learn the opponents while negotiating. We find strategies can be augmented by collaborativeness analysis: the approximate collaborativeness metric can be used to cut short the negotiation. Then, we discover an approach to model the opponent through Bayesian learning. We assume the agents do not disclose their information voluntarily: the learning needs to rely on the study of the offers exchanged during normal negotiation. At last, we explore a setting where the agents are able to perform physical action (movement) while the negotiation is ongoing. We formalize a method to represent and update the beliefs about the valuation function, the current state of negotiation and strategy of the opponent agent using a particle filter. By exploring a number of different negotiation protocols and several peer-to-peer negotiation based strategies, we claim that the CRF problem captures the main challenges of the real world problems while allows us to simplify away some of the computationally demanding but semantically marginal features of real world problems.
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Date Issued: 2011
Identifier: CFE0003722, ucf:48782
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003722

Title: A framework to generate a smart manufacturing system configurations using agents and optimization.
Creator: Nagadi, Khalid, Rabelo, Luis, Lee, Gene, Elshennawy, Ahmad, Ahmad, Ali, University of Central Florida
Abstract / Description: Manufacturing is a crucial element in the global economy. During the last decade, the national manufacturing sector loses nearly 30% of its workforce and investments. Consequently, the quality of the domestic goods, global share, and manufacturing capabilities has been declined. Therefore, innovative ways to optimize the usage of the Smart Manufacturing Systems (SMS) are required to form a new manufacturing era. This research is presenting a framework to optimize the design of SMS. This...
Show moreManufacturing is a crucial element in the global economy. During the last decade, the national manufacturing sector loses nearly 30% of its workforce and investments. Consequently, the quality of the domestic goods, global share, and manufacturing capabilities has been declined. Therefore, innovative ways to optimize the usage of the Smart Manufacturing Systems (SMS) are required to form a new manufacturing era. This research is presenting a framework to optimize the design of SMS. This includes the determination of the suitable machines that can perform the job efficiently, the quantity of those machines, and the potential messaging system required for sharing information.Multiple reviews are used to form the framework. Expert machine selection matrix identifies the required machines and machine parameter matrix defines the specifications of those machines. While business process modeling and notation (BPMN) captures the process plan in object-oriented fashion. In addition, to agent unified modeling language (AUML) that guides the application of message sequence diagram and statecharts. Finally, the configuration is obtained from a hybrid simulation model. Agent based-modeling is used to capture the behavior of the machines where discrete event simulation mimics the process flow. A case study of a manufacturing system is used to verify the study. As a result, the framework shows positive outcomes in supporting upper management in the planning phase of establishing a SMS or evaluating an existing one.
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Date Issued: 2016
Identifier: CFE0006540, ucf:51311
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006540

Title: Differential Games for Multi-Agent Systems under Distributed Information.
Creator: Lin, Wei, Qu, Zhihua, Simaan, Marwan, Haralambous, Michael, Das, Tuhin, Yong, Jiongmin, University of Central Florida
Abstract / Description: In this dissertation, we consider differential games for multi-agent systems under distributed information where every agent is only able to acquire information about the others according to a directed information graph of local communication/sensor networks. Such games arise naturally from many applications including mobile robot coordination, power system optimization, multi-player pursuit-evasion games, etc. Since the admissible strategy of each agent has to conform to the information...
Show moreIn this dissertation, we consider differential games for multi-agent systems under distributed information where every agent is only able to acquire information about the others according to a directed information graph of local communication/sensor networks. Such games arise naturally from many applications including mobile robot coordination, power system optimization, multi-player pursuit-evasion games, etc. Since the admissible strategy of each agent has to conform to the information graph constraint, the conventional game strategy design approaches based upon Riccati equation(s) are not applicable because all the agents are required to have the information of the entire system. Accordingly, the game strategy design under distributed information is commonly known to be challenging. Toward this end, we propose novel open-loop and feedback game strategy design approaches for Nash equilibrium and noninferior solutions with a focus on linear quadratic differential games. For the open-loop design, approximate Nash/noninferior game strategies are proposed by integrating distributed state estimation into the open-loop global-information Nash/noninferior strategies such that, without global information, the distributed game strategies can be made arbitrarily close to and asymptotically converge over time to the global-information strategies. For the feedback design, we propose the best achievable performance indices based approach under which the distributed strategies form a Nash equilibrium or noninferior solution with respect to a set of performance indices that are the closest to the original indices. This approach overcomes two issues in the classical optimal output feedback approach: the simultaneous optimization and initial state dependence. The proposed open-loop and feedback design approaches are applied to an unmanned aerial vehicle formation control problem and a multi-pursuer single-evader differential game problem, respectively. Simulation results of several scenarios are presented for illustration.
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Date Issued: 2013
Identifier: CFE0005025, ucf:49991
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005025

Title: Identifying Influential Agents in Social Systems.
Creator: Maghami, Mahsa, Sukthankar, Gita, Turgut, Damla, Wu, Annie, Boloni, Ladislau, Garibay, Ivan, University of Central Florida
Abstract / Description: This dissertation addresses the problem of influence maximization in social networks. Influence maximization is applicable to many types of real-world problems, including modeling contagion, technology adoption, and viral marketing. Here we examine an advertisement domain in which the overarching goal is to find the influential nodes in a social network, based on the network structure and the interactions, as targets of advertisement. The assumption is that advertisement budget limits prevent...
Show moreThis dissertation addresses the problem of influence maximization in social networks. Influence maximization is applicable to many types of real-world problems, including modeling contagion, technology adoption, and viral marketing. Here we examine an advertisement domain in which the overarching goal is to find the influential nodes in a social network, based on the network structure and the interactions, as targets of advertisement. The assumption is that advertisement budget limits prevent us from sending the advertisement to everybody in the network. Therefore, a wise selection of the people can be beneficial in increasing the product adoption. To model these social systems, agent-based modeling, a powerful tool for the study of phenomena that are difficult to observe within the confines of the laboratory, is used.To analyze marketing scenarios, this dissertation proposes a new method for propagating information through a social system and demonstrates how it can be used to develop a product advertisement strategy in a simulated market. We consider the desire of agents toward purchasing an item as a random variable and solve the influence maximization problem in steady state using an optimization method to assign the advertisement of available products to appropriate messenger agents. Our market simulation 1) accounts for the effects of group membership on agent attitudes 2) has a network structure that is similar to realistic human systems 3) models inter-product preference correlations that can be learned from market data. The results on synthetic data show that this method is significantly better than network analysis methods based on centrality measures.The optimized influence maximization (OIM) described above, has some limitations. For instance, it relies on a global estimation of the interaction among agents in the network, rendering it incapable of handling large networks. Although OIM is capable of finding the influential nodes in the social network in an optimized way and targeting them for advertising, in large networks, performing the matrix operations required to find the optimized solution is intractable.To overcome this limitation, we then propose a hierarchical influence maximization (HIM) algorithm for scaling influence maximization to larger networks. In the hierarchical method the network is partitioned into multiple smaller networks that can be solved exactly with optimization techniques, assuming a generalized IC model, to identify a candidate set of seed nodes. The candidate nodes are used to create a distance-preserving abstract version of the network that maintains an aggregate influence model between partitions. The budget limitation for the advertising dictates the algorithm's stopping point. On synthetic datasets, we show that our method comes close to the optimal node selection, at substantially lower runtime costs.We present results from applying the HIM algorithm to real-world datasets collected from social media sites with large numbers of users (Epinions, SlashDot, and WikiVote) and compare it with two benchmarks, PMIA and DegreeDiscount, to examine the scalability and performance.Our experimental results reveal that HIM scales to larger networks but is outperformed by degree-based algorithms in highly-connected networks. However, HIM performs well in modular networks where the communities are clearly separable with small number of cross-community edges. This finding suggests that for practical applications it is useful to account for network properties when selecting an influence maximization method.
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Date Issued: 2014
Identifier: CFE0005205, ucf:50647
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005205

Title: MODELING AUTONOMOUS AGENTS IN MILITARY SIMULATIONS.
Creator: Kaptan, Varol, Gelenbe, Erol, University of Central Florida
Abstract / Description: Simulation is an important tool for prediction and assessment of the behavior of complex systems and situations. The importance of simulation has increased tremendously during the last few decades, mainly because the rapid pace of development in the field of electronics has turned the computer from a costly and obscure piece of equipment to a cheap ubiquitous tool which is now an integral part of our daily lives. While such technological improvements make it easier to analyze well-understood...
Show moreSimulation is an important tool for prediction and assessment of the behavior of complex systems and situations. The importance of simulation has increased tremendously during the last few decades, mainly because the rapid pace of development in the field of electronics has turned the computer from a costly and obscure piece of equipment to a cheap ubiquitous tool which is now an integral part of our daily lives. While such technological improvements make it easier to analyze well-understood deterministic systems, increase in speed and storage capacity alone are not enough when simulating situations where human beings and their behavior are an integral part of the system being studied. The problem with simulation of intelligent entities is that intelligence is still not well understood and it seems that the field of Artificial Intelligence (AI) has a long way to go before we get computers to think like humans. Behavior-based agent modeling has been proposed in mid-80's as one of the alternatives to the classical AI approach. While used mainly for the control of specialized robotic vehicles with very specific sensory capabilities and limited intelligence, we believe that a behavior-based approach to modeling generic autonomous agents in complex environments can provide promising results. To this end, we are investigating a behavior-based model for controlling groups of collaborating and competing agents in a geographic terrain. In this thesis, we are focusing on scenarios of military nature, where agents can move within the environment and adversaries can eliminate each other through use of weapons. Different aspects of agent behavior like navigation to a goal or staying in group formation, are implemented by distinct behavior modules and the final observed behavior for each agent is an emergent property of the combination of simple behaviors and their interaction with the environment. Our experiments show that while such an approach is quite efficient in terms of computational power, it has some major drawbacks. One of the problems is that reactive behavior-based navigation algorithms are not well suited for environments with complex mobility constraints where they tend to perform much worse than proper path planning. This problem represents an important research question, especially when it is considered that most of the modern military conflicts and operations occur in urban environments. One of the contributions of this thesis is a novel approach to reactive navigation where goals and terrain information are fused based on the idea of transforming a terrain with obstacles into a virtual obstacle-free terrain. Experimental results show that our approach can successfully combine the low run-time computational complexity of reactive methods with the high success rates of classical path planning. Another interesting research problem is how to deal with the unpredictable nature of emergent behavior. It is not uncommon to have situations where an outcome diverges significantly from the intended behavior of the agents due to highly complex nonlinear interactions with other agents or the environment itself. Chances of devising a formal way to predict and avoid such abnormalities are slim at best, mostly because such complex systems tend to be be chaotic in nature. Instead, we focus on detection of deviations through tracking group behavior which is a key component of the total situation awareness capability required by modern technology-oriented and network-centric warfare. We have designed a simple and efficient clustering algorithm for tracking of groups of agent suitable for both spatial and behavioral domain. We also show how to detect certain events of interest based on a temporal analysis of the evolution of discovered clusters.
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Date Issued: 2006
Identifier: CFE0001494, ucf:47099
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001494

Title: Transparency in human-agent teaming and its effect on complacent behavior.
Creator: Wright, Julia, Hancock, Peter, Szalma, James, Jentsch, Florian, Chen, Jessie, University of Central Florida
Abstract / Description: This study examined how transparency of an intelligent agent's reasoning affected complacent behavior in a route selection task in a simulated environment. Also examined was how the information available to the operator affected those results.In two experiments, participants supervised a three-vehicle convoy as it traversed a simulated environment and re-routed the convoy when needed with the assistance of an intelligent agent, RoboLeader. Participants were randomly assigned to an Agent...
Show moreThis study examined how transparency of an intelligent agent's reasoning affected complacent behavior in a route selection task in a simulated environment. Also examined was how the information available to the operator affected those results.In two experiments, participants supervised a three-vehicle convoy as it traversed a simulated environment and re-routed the convoy when needed with the assistance of an intelligent agent, RoboLeader. Participants were randomly assigned to an Agent Reasoning Transparency condition. Participants received communications from a commander confirming either the presence or absence of activity in the area. They also received information regarding potential events along their route via icons that appeared on a map displaying the convoy route and surrounding area. Participants in Experiment 1 (low information setting) received information about their current route only; they did not receive any information about the suggested alternate route. Participants in Experiment 2 (high information setting) received information about both their current route and the agent recommended an alternative route. In the first experiment, access to agent reasoning was found to be an effective deterrent to complacent behavior when the operator has limited information about their task environment. However, the addition of information that created ambiguity for the operator encouraged complacency, resulting in reduced performance and poorer trust calibration. Agent reasoning did not increase response time or workload and appeared to have improved performance on the secondary task. These findings align with studies that have shown ambiguous information can increase workload and encourage complacency, as such, caution should be exercised when considering how transparent to make agent reasoning and what information should be included.In the second experiment, access to agent reasoning was found to have little effect on complacent behavior when the operator had complete information about the task environment. However, the addition of information that created ambiguity for the operator appeared to encourage complacency, as indicated by reduced performance and shorter decision times. Agent reasoning transparency did not increase overall workload, and operators reported higher satisfaction with their performance and reduced mental demand. Access to agent reasoning did not improve operators' secondary task performance, situation awareness, or operator trust. However, when agent reasoning transparency included ambiguous information complacent behavior was again encouraged. Unlike the first experiment, there were notable differences in complacent behavior, performance, operator trust, and situation awareness due to individual difference factors. As such, these findings would suggest that when the operator has complete information regarding their task environment, access to agent reasoning may be beneficial, but not dramatically so. However, individual difference factors will greatly influence performance outcomes. The amount of information the operator has regarding the task environment has a profound effect on the proper use of the agent. Increased environmental information resulted in more rejections of the agent recommendation regardless of the transparency of agent reasoning. The addition of agent reasoning transparency appeared to be effective at keeping the operator engaged, while complacent behavior appeared to be encouraged both when agent reasoning was either not transparent or so transparent as to become ambiguous. Even so, operators reported lower trust and usability for the agent than when environmental information was limited. Situation awareness (SA2) scores were also higher in the high information environment when agent reasoning was either not transparent or so transparent as to become ambiguous, compared to the low information environment. However, when a moderate amount of agent reasoning was available to the operator, the amount of information available to the operator had no effect on the operators' complacent behavior, subjective trust, or SA. These findings indicate that some negative outcomes resulting from the incongruous transparency of agent reasoning may be mitigated by increasing the information the operator has regarding the task environment.
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Date Issued: 2016
Identifier: CFE0006422, ucf:51469
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006422

Title: Towards Improving Human-Robot Interaction For Social Robots.
Creator: Khan, Saad, Boloni, Ladislau, Behal, Aman, Sukthankar, Gita, Garibay, Ivan, Fiore, Stephen, University of Central Florida
Abstract / Description: Autonomous robots interacting with humans in a social setting must consider the social-cultural environment when pursuing their objectives. Thus the social robot must perceive and understand the social cultural environment in order to be able to explain and predict the actions of its human interaction partners. This dissertation contributes to the emerging field of human-robot interaction for social robots in the following ways: 1. We used the social calculus technique based on culture...
Show moreAutonomous robots interacting with humans in a social setting must consider the social-cultural environment when pursuing their objectives. Thus the social robot must perceive and understand the social cultural environment in order to be able to explain and predict the actions of its human interaction partners. This dissertation contributes to the emerging field of human-robot interaction for social robots in the following ways: 1. We used the social calculus technique based on culture sanctioned social metrics (CSSMs) to quantify, analyze and predict the behavior of the robot, human soldiers and the public perception in the Market Patrol peacekeeping scenario. 2. We validated the results of the Market Patrol scenario by comparing the predicted values with the judgment of a large group of human observers cognizant of the modeled culture. 3. We modeled the movement of a socially aware mobile robot in a dense crowds, using the concept of a micro-conflict to represent the challenge of giving or not giving way to pedestrians. 4. We developed an approach for the robot behavior in micro-conflicts based on the psychological observation that human opponents will use a consistent strategy. For this, the mobile robot classifies the opponent strategy reflected by the personality and social status of the person and chooses an appropriate counter-strategy that takes into account the urgency of the robots' mission. 5. We developed an alternative approach for the resolution of micro-conflicts based on the imitation of the behavior of the human agent. This approach aims to make the behavior of an autonomous robot closely resemble that of a remotely operated one.
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Date Issued: 2015
Identifier: CFE0005965, ucf:50819
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005965

Title: DEVELOPING STRAND SPACE BASED MODELS AND PROVING THE CORRECTNESS OF THE IEEE 802.11I AUTHENTICATION PROTOCOL WITH RESTRICTED SECURITY OBJECTIVES.
Creator: Furqan, Zeeshan, Guha, Ratan, University of Central Florida
Abstract / Description: The security objectives enforce the security policy, which defines what is to be protected in a network environment. The violation of these security objectives induces security threats. We introduce an explicit notion of security objectives for a security protocol. This notion should precede the formal verification process. In the absence of such a notion, the security protocol may be proven correct despite the fact that it is not equipped to defend against all potential threats. In order to...
Show moreThe security objectives enforce the security policy, which defines what is to be protected in a network environment. The violation of these security objectives induces security threats. We introduce an explicit notion of security objectives for a security protocol. This notion should precede the formal verification process. In the absence of such a notion, the security protocol may be proven correct despite the fact that it is not equipped to defend against all potential threats. In order to establish the correctness of security objectives, we present a formal model that provides basis for the formal verification of security protocols. We also develop the modal logic, proof based, and multi-agent approaches using the Strand Space framework. In our modal logic approach, we present the logical constructs to model a protocol's behavior in such a way that the participants can verify different security parameters by looking at their own run of the protocol. In our proof based model, we present a generic set of proofs to establish the correctness of a security protocol. We model the 802.11i protocol into our proof based system and then perform the formal verification of the authentication property. The intruder in our model is imbued with powerful capabilities and repercussions to possible attacks are evaluated. Our analysis proves that the authentication of 802.11i is not compromised in the presented model. We further demonstrate how changes in our model will yield a successful man-in-the-middle attack. Our multi-agent approach includes an explicit notion of multi-agent, which was missing in the Strand Space framework. The limitation of Strand Space framework is the assumption that all the information available to a principal is either supplied initially or is contained in messages received by that principal. However, other important information may also be available to a principal in a security setting, such as a principal may combine information from different roles played by him in a protocol to launch a powerful attack. Our presented approach models the behavior of a distributed system as a multi-agent system. The presented model captures the combined information, the formal model of knowledge, and the belief of agents over time. After building this formal model, we present a formal proof of authentication of the 4-way handshake of the 802.11i protocol.
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Date Issued: 2007
Identifier: CFE0001801, ucf:47380
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001801

Title: CHARACTERIZATION OF DISPERSION AND RESIDUAL STRESS IN NANOPARTICLE REINFORCED HYBRID CARBON FIBER COMPOSITES.
Creator: Selimov, Alex, Raghavan,Seetha, University of Central Florida
Abstract / Description: Hybrid carbon fiber reinforced composites are a new breed of materials that are currently being explored and characterized for next generation aerospace applications. Through the introduction of secondary reinforcements, such as alumina nanoparticles, hybrid properties including improved mechanical properties and stress sensing capabilities can be achieved. In order to maximize these properties, it is necessary to achieve a homogeneous dispersion of particulate filler. Utilizing the...
Show moreHybrid carbon fiber reinforced composites are a new breed of materials that are currently being explored and characterized for next generation aerospace applications. Through the introduction of secondary reinforcements, such as alumina nanoparticles, hybrid properties including improved mechanical properties and stress sensing capabilities can be achieved. In order to maximize these properties, it is necessary to achieve a homogeneous dispersion of particulate filler. Utilizing the photoluminescent properties of alumina, it is possible to compare local levels of particle concentration through emission intensities as a way to determine the effectiveness of the tested manufacturing parameters in increasing material homogeneity. Parameters of these photoluminescence emissions have been established to be stress dependent, which allows for in situ residual stress measurements. It is shown here that the application of silane coupling agents as particle surface treatments improves particle dispersion when compared to untreated samples. Reactive silane coupling agent (RSCA) treatments were found to provide for greater dispersion improvements when compared to non-reactive silane coupling agents (NRSCA). Higher resolution investigations into these samples found that treatment with a reactive coupling agent altered the stress state of particles concentrated around the fiber from a tensile stress state to a compressive stress state. This is proposed to result from bonding of the reactive groups on the coupling agent to the organic groups on the carbon fibers which adjusts the stress state of the particle. Future mechanical tests will verify the effects of the particle surface functionalization treatments on mechanical properties of the composites.
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Date Issued: 2016
Identifier: CFH0000233, ucf:44669
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFH0000233

System Dynamics (4)	+ -
multi-agent systems (4)	+ -
simulation (4)	+ -
Simulation (3)	+ -
agent-based modeling (3)	+ -

Agent (2)	+ -
Agent Based Modeling (2)	+ -
Agent Based Simulation (2)	+ -
Agent-Based (2)	+ -
Internet of Things (2)	+ -
Modeling (2)	+ -
Multi-agent system (2)	+ -
agency (2)	+ -
artificial intelligence (2)	+ -
augmented reality (2)	+ -
avatar (2)	+ -
education (2)	+ -
mixed reality (2)	+ -
modeling (2)	+ -
presence (2)	+ -
802.11i (1)	+ -
Advertising (1)	+ -
Agent Based (1)	+ -
Agent system (1)	+ -
Agent-Based Simulation (1)	+ -
Agent-Causal (1)	+ -
Agent-Cause (1)	+ -
Agents (1)	+ -
Alternate Possibilities (1)	+ -
Alternative Possibilities (1)	+ -

ETD Collection (43)	+ -
Honors Collection (4)	+ -

University of Central Florida (47)	+ -
Boloni, Ladislau (6)	+ -
Sukthankar, Gita (6)	+ -
Elshennawy, Ahmad (5)	+ -
Kincaid, John (5)	+ -

Karwowski, Waldemar (4)	+ -
Lee, Gene (4)	+ -
Rabelo, Luis (4)	+ -
Das, Tuhin (3)	+ -
Fiore, Stephen (3)	+ -
Gonzalez, Avelino (3)	+ -
Hancock, Peter (3)	+ -
Hughes, Charles (3)	+ -
Turgut, Damla (3)	+ -
Wu, Annie (3)	+ -
Xanthopoulos, Petros (3)	+ -
Bruder, Gerd (2)	+ -
Garibay, Ivan (2)	+ -
Guha, Ratan (2)	+ -
Jayasuriya, Suhada (2)	+ -
Jentsch, Florian (2)	+ -
Proctor, Michael (2)	+ -
Qu, Zhihua (2)	+ -
Simaan, Marwan (2)	+ -
Welch, Gregory (2)	+ -
Wiegand, Rudolf (2)	+ -
Ahmad, Ali (1)	+ -
Ajayi, Richard (1)	+ -
Akbas, Ilhan (1)	+ -
Amezcua Correa, Rodrigo (1)	+ -

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