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- Title
- A framework for prioritizing opportunities of improvement in the context of business excellence model in healthcare organization.
- Creator
-
Aldarmaki, Alia, Elshennawy, Ahmad, Lee, Gene, Rabelo, Luis, Darwish, Mohammed, University of Central Florida
- Abstract / Description
-
In today's world, the healthcare sector is facing challenges to improve the efficiency and effectiveness of its operations. More and more improvement projects are being adopted to enhance healthcare services, making it more patient-centric, and enabling better cost control. Healthcare organizations strive to identify and carry out such improvement initiatives to sustain their businesses and gain competitive advantage. Seeking to reach a higher operational level of excellence, healthcare...
Show moreIn today's world, the healthcare sector is facing challenges to improve the efficiency and effectiveness of its operations. More and more improvement projects are being adopted to enhance healthcare services, making it more patient-centric, and enabling better cost control. Healthcare organizations strive to identify and carry out such improvement initiatives to sustain their businesses and gain competitive advantage. Seeking to reach a higher operational level of excellence, healthcare organizations utilize business excellence criteria to conduct assessment and identify organizational strengths and weaknesses. However, while such assessments routinely identify numerous areas for potential improvement, it is not feasible to conduct all improvement projects simultaneously due to limitations in time, capital, and personnel, as well as conflict with other organization's projects or strategic objectives. An effective prioritization and selection approach is valuable in that it can assist the organization to optimize its available resources and outcomes. This study attempts to enable such an approach by developing a framework to prioritize improvement opportunities in healthcare in the context of the business excellence model through the integration of the Fuzzy Delphi Method and Fuzzy Interface System. To carry out the evaluation process, the framework consists of two phases. The first phase utilizes Fuzzy Delphi Method to identify the most significant factors that should be considered in healthcare for electing the improvement projects. The FDM is employed to handle the subjectivity of human assessment. The research identifies potential factors for evaluating projects, then utilizes FDM to capture expertise knowledge. The first round in FDM is intended to validate the identified list of factors from experts; which includes collecting additional factors from experts that the literature might have overlooked. When an acceptable level of consensus has been reached, a second round is conducted to obtain experts' and other related stakeholders' opinions on the appropriate weight of each factor's importance. Finally, FDM analyses eliminate or retain the criteria to produce a final list of critical factors to select improvement projects. The second phase in the framework attempts to prioritize improvement initiatives using the Hierarchical Fuzzy Interface System. The Fuzzy Interface System combines the experts' ratings for each improvement opportunity with respect to the factors deemed critical to compute the priority index. In the process of calculating the priority index, the framework allows the estimation of other intermediate indices including: social, financial impact, strategical, operational feasibility, and managerial indices. These indices bring an insight into the improvement opportunities with respect to each framework's dimensions. The framework allows for a reduction of the bias in the assessment by developing a knowledge based on the perspectives of multiple experts.
Show less - Date Issued
- 2018
- Identifier
- CFE0007304, ucf:52158
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007304
- Title
- Two Pathways To Performance: Affective- and Motivationally-Driven Development In Virtual Multiteam Systems.
- Creator
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Jimenez, Miliani, Dechurch, Leslie, Salas, Eduardo, Bowers, Clint, Zaccaro, Stephen, University of Central Florida
- Abstract / Description
-
Multiteam systems are an integral part of our daily lives. We witness these entities in natural disaster responses teams, such as the PB Oil Spill and Hurricane Katrina, governmental agencies, such as the CIA and FBI, working behind the scenes to preemptively disarm terrorist attacks, within branches of the Armed Forces, within our organizations, and in science teams aiming to find a cure for cancer (Goodwin, Essens, (&) Smith, 2012; Marks (&) Luvison, 2012). Two key features of the...
Show moreMultiteam systems are an integral part of our daily lives. We witness these entities in natural disaster responses teams, such as the PB Oil Spill and Hurricane Katrina, governmental agencies, such as the CIA and FBI, working behind the scenes to preemptively disarm terrorist attacks, within branches of the Armed Forces, within our organizations, and in science teams aiming to find a cure for cancer (Goodwin, Essens, (&) Smith, 2012; Marks (&) Luvison, 2012). Two key features of the collaborative efforts of multiteam systems are the exchange of information both within and across component team boundaries as well as the virtual tools employed to transfer information between teams (Keyton, Ford, (&) Smith, 2012; Zaccaro, Marks, (&) DeChurch, 2012).The goal of this dissertation was to shed light on enabling the effectiveness of multiteam systems. One means of targeting this concern was to provide insight on the underpinnings of MTS mechanism and how they evolve. The past 20 years of research on teams supports the central role of motivational and affective states (Kozlowski (&) Ilgen, 2006; and Mathieu, Maynard, Rapp, (&) Gibson, 2008) as critical drivers of performance. Therefore it was my interest to understand how these critical team mechanisms unravel at the multiteam system level and understanding how they influence the development of other important multiteam system processes and emergent states. Specifically, this dissertation focused on the influence motivational and affective emergent states (such as multiteam efficacy and multiteam trust) have on shaping behavioral processes (such as information sharing-unique and open) and cognitive emergent states (such as Transactive memory systems and shared mental models). Findings from this dissertation suggest that multiteam efficacy is a driver of open information sharing in multiteam systems and both types of cognitive emergent states (transactive memory systems and shared mental models). Multiteam trust was also found to be a critical driver of open information sharing and the cognitive emergent state transactive memory systems.Understanding that these mechanisms do not evolve in isolation, it was my interest to study them under a growing contextual state that is continuously infiltrating our work lives today, under virtual collaboration. This dissertation sought to uncover how the use of distinct forms of virtual tools, media rich tools and media retrievability tools, enable multiteam systems to develop needed behavioral processes and cognitive emergent states. Findings suggest that the use of media retrievability tools interacted with the task mental models in promoting the exchange of unique information both between and within component teams of a multiteam system.The implications of these findings are twofold. First, since both motivational and affective emergent states of members within multiteam systems are critical drivers of behavioral processes, cognitive emergent states, and in turn multiteam system performance; future research should explore how we can diagnose as well as target the development of multiteam system level efficacy and trust. Second, the virtual communication tools that provide multiteam systems members the ability to review discussed materials at a later point in time are critical for sharing information both within and across component teams depending on the level of shared cognition that multiteam system members possess of the task.Therefore the ability to encourage the use and provide such tools for collaborative purposes is beneficial for the successful collaboration of multiteam systems.
Show less - Date Issued
- 2012
- Identifier
- CFE0004389, ucf:52872
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004389
- Title
- Three Studies Examining the Effects of Business Analytics on Judgment and Decision Making in Accounting.
- Creator
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Lang, Bradley, Trompeter, Gregory, Robb, Sean, Tian, Yu, Trinkle, Brad, University of Central Florida
- Abstract / Description
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This dissertation consists of three studies investigating the relationship between business analytics and decision making in accounting. In an effort to improve performance, organizations increasingly emphasize fact-based decision making supported by business analytics, which translate complex data into manageable information through statistical analysis. While the recent focus on business analytics is transforming how managers make decisions, analytics alone do not generate increased...
Show moreThis dissertation consists of three studies investigating the relationship between business analytics and decision making in accounting. In an effort to improve performance, organizations increasingly emphasize fact-based decision making supported by business analytics, which translate complex data into manageable information through statistical analysis. While the recent focus on business analytics is transforming how managers make decisions, analytics alone do not generate increased performance; the synergy between business analytics and user judgments is a vital component of realizing value. To this end, Study I experimentally investigates how various characteristics of business analytics affect individuals' reliance and perceptions of the analytic. Through the lens of cognitive fit a 2(&)#215;2 between-subjects experiment is conducted examining business analytics effects of input and process attributes on users' reliance. Cognitive fit theory posits that effective problem solving depends on the match between the technology and the decision process. The second study investigates the impact of management interventions (i.e. actions influencing adoption) toward improving reliance on business analytics. From an organizational perspective, an important concern for management is promoting greater employee acceptance and utilization of business analytics. Building on the Technology Acceptance Model, Study II experimentally examines the effect of management support and consensus of multiple analytics on increasing reliance and on participants' evaluation of the business analytic. Study III further explores the relationship between characteristics of business analytics and the decision maker by developing a theoretical model regarding the effects of perceived decision similarities between the user and the business analytic on users' perceived usefulness. Overall, the results reported in this dissertation suggest that 1) characteristics of business analytics influence users' judgments and decision making, 2) management can take actions to influence the relationship between users and business analytics, and 3) users are likely to evaluate their cognitive similarity to these business analytics, and these perceptions influence perceived usefulness of the business analytics.
Show less - Date Issued
- 2018
- Identifier
- CFE0007578, ucf:52562
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007578
- Title
- Evaluating Hydrologic Fluxes Through Stormwater Treatment Systems: Implication to Freshwater Springs in a Karst Environment.
- Creator
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Rice, Nyle, Kibler, Kelly, Wang, Dingbao, Chang, Ni-bin, University of Central Florida
- Abstract / Description
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In recent years, concentrations of nutrients such as nitrogen and phosphorus have increased in surface and groundwater resources, due in part to non-point source pollution associated with stormwater runoff. The elevated nutrient concentrations found in stormwater runoff have prompted the design of best management practices (BMP's) to mitigate the problem. The overall objective within this thesis is to analyze the performance of innovative surface BMPs and investigate connections between the...
Show moreIn recent years, concentrations of nutrients such as nitrogen and phosphorus have increased in surface and groundwater resources, due in part to non-point source pollution associated with stormwater runoff. The elevated nutrient concentrations found in stormwater runoff have prompted the design of best management practices (BMP's) to mitigate the problem. The overall objective within this thesis is to analyze the performance of innovative surface BMPs and investigate connections between the BMPs and groundwater flows to freshwater springs within a karst environment. The performance of two stormwater BMPs, blanket filters and vertical reactors containing Bio-sorption Activated Media (BAM), are assessed in terms of hydraulic retention time. Capture efficiency is also evaluated for the blanket filters. Blanket filters captured, at minimum 68% of the stormwater runoff entering a stormwater basin in one year. Water content monitoring indicates that BAM is affected by the surrounding water table. The vertical reactors are more appropriate technologies for small contributing areas. Tracking a conservative tracer from an injection point within a stormwater basin to nearby Silver Springs reveals several unique flowpaths and velocities of groundwater. Subsurface velocities observed in the basin ranged from 0.1 m/d to 1.4 m/d, while velocities from the injection well to the spring vary from 2.3 m/d to 13.5 m/d. The fastest travel times observed in the spring may represent flowpaths that include macropore/conduit flow through karst features, while the slower peaks may be more representative of matrix flow. Interaction with karst features may reduce retention time of stormwater in aquifers, altering expected nutrient transformations. Understanding the variable pathways stormwater may take from the surface to spring discharge may assist environmental managers in preserving water quality in springs and other waterbodies in karst systems.
Show less - Date Issued
- 2018
- Identifier
- CFE0007241, ucf:52219
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007241
- Title
- A System Dynamics Approach on Sustainability Assessment of the United States Urban Commuter Transportation.
- Creator
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Ercan, Tolga, Tatari, Omer, Oloufa, Amr, Eluru, Naveen, Xanthopoulos, Petros, University of Central Florida
- Abstract / Description
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Transportation sector is one of the largest emission sources and is a cause for human health concern due to the high dependency on personal vehicle in the U.S. Transportation mode choice studies are currently limited to micro- and regional-level boundaries, lacking of presenting a complete picture of the issues, and the root causes associated with urban passenger transportation choices in the U.S. Hence, system dynamics modeling approach is utilized to capture complex causal relationships...
Show moreTransportation sector is one of the largest emission sources and is a cause for human health concern due to the high dependency on personal vehicle in the U.S. Transportation mode choice studies are currently limited to micro- and regional-level boundaries, lacking of presenting a complete picture of the issues, and the root causes associated with urban passenger transportation choices in the U.S. Hence, system dynamics modeling approach is utilized to capture complex causal relationships among the critical system parameters affecting alternative transportation mode choices in the U.S. as well as to identify possible policy areas to improve alternative transportation mode choice rates for future years up to 2050. Considering the high degree of uncertainties inherent to the problem, multivariate sensitivity analysis is utilized to explore the effectiveness of existing and possible policy implications in dynamic model in the terms of their potential to increase transit ridership and locating critical parameters that influences the most on mode choice and emission rates. Finally, the dissertation advances the current body of knowledge by integrating discrete event simulation (multinomial fractional split model) and system dynamics for hybrid urban commuter transportation simulation to test new scenarios such as autonomous vehicle (AV) adoption along with traditional policy scenarios such as limiting lane-mile increase on roadways and introducing carbon tax policy on vehicle owners. Overall, the developed simulation models clearly indicate the importance of urban structures to secure the future of alternative transportation modes in the U.S. as the prevailing policy practices fail to change system behavior. Thus, transportation system needs a paradigm shift to radically change current impacts and the market penetration of AVs can be one of the reforms to provoke this transition since it is expected to revolutionize mode choice, emission trends, and the built environment.
Show less - Date Issued
- 2019
- Identifier
- CFE0007626, ucf:52554
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007626
- Title
- Evaluation of Postoperative Air Leak and Chest Tube Drainage Systems after Pulmonary Resection.
- Creator
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Jacobsen, Kristina, Talbert, Steven, Sole, Mary Lou, Guido-Sanz, Francisco, Bittner, Hartmuth, University of Central Florida
- Abstract / Description
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Postoperative air leaks are the most common complication after a pulmonary resection. There is no data in the literature comparing the traditional and digital chest drainage system after a robotic-assisted pulmonary lobectomy. In 182 eligible patients, this retrospective study evaluated the association between digital and traditional drainage systems with postoperative chest tube days, hospital length of stay, chest tube reinsertion during hospitalization, and 30-day readmission for...
Show morePostoperative air leaks are the most common complication after a pulmonary resection. There is no data in the literature comparing the traditional and digital chest drainage system after a robotic-assisted pulmonary lobectomy. In 182 eligible patients, this retrospective study evaluated the association between digital and traditional drainage systems with postoperative chest tube days, hospital length of stay, chest tube reinsertion during hospitalization, and 30-day readmission for pneumothorax following a robotic-assisted lobectomy. The groups did not differ significantly in terms of age, gender, BMI, smoking, adhesions or neoadjuvant therapy. Patients with the digital drainage system had a mean chest tube duration of 2.07 days compared with 2.73 days for the traditional drainage system (p = 0.003). Hospital length of stay was also significantly reduced with the digital drainage system. Patients using the digital drainage system had a mean hospital length of stay of 4.02 days compared with 5.06 days with the traditional drainage system (p = 0.010). Although chest tube reinsertion occurred four times more frequently with traditional drainage system, the difference did not achieve the level of statistical significance (p = 0.059). The frequency of readmission due to pneumothorax was very low (1 patient per group), which prevented comparative statistical analysis. In the digital drainage system there are shorter chest tube days and hospital length of stay after a robotic-assisted lobectomy. The decision to remove chest tubes in the traditional drainage system is burdened with uncertainty. The digital drainage system reduces intraobserver variability allowing for improved decision making in chest tube removal.
Show less - Date Issued
- 2019
- Identifier
- CFE0007893, ucf:52771
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007893
- Title
- MEASURING AND IMPROVING INTERNET VIDEO QUALITY OF EXPERIENCE.
- Creator
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Iyengar, Mukundan, Chatterjee, Mainak, University of Central Florida
- Abstract / Description
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Streaming multimedia content over the IP-network is poised to be the dominant Internet traffic for the coming decade, predicted to account for more than 91% of all consumer traffic in the coming years. Streaming multimedia content ranges from Internet television (IPTV), video on demand (VoD), peer-to-peer streaming, and 3D television over IP to name a few. Widespread acceptance, growth, and subscriber retention are contingent upon network providers assuring superior Quality of Experience (QoE...
Show moreStreaming multimedia content over the IP-network is poised to be the dominant Internet traffic for the coming decade, predicted to account for more than 91% of all consumer traffic in the coming years. Streaming multimedia content ranges from Internet television (IPTV), video on demand (VoD), peer-to-peer streaming, and 3D television over IP to name a few. Widespread acceptance, growth, and subscriber retention are contingent upon network providers assuring superior Quality of Experience (QoE) on top of todays Internet. This work presents the first empirical understanding of Internet's video-QoE capabilities, and tools and protocols to efficiently infer and improve them. To infer video-QoE at arbitrary nodes in the Internet, we design and implement MintMOS: a lightweight, real-time, no-reference framework for capturing perceptual quality. We demonstrate that MintMOS's projections closely match with subjective surveys in accessing perceptual quality. We use MintMOS to characterize Internet video-QoE both at the link level and end-to-end path level. As an input to our study, we use extensive measurements from a large number of Internet paths obtained from various measurement overlays deployed using PlanetLab. Link level degradations of intra-- and inter--ISP Internet links are studied to create an empirical understanding of their shortcomings and ways to overcome them. Our studies show that intra--ISP links are often poorly engineered compared to peering links, and that degradations are induced due to transient network load imbalance within an ISP. Initial results also indicate that overlay networks could be a promising way to avoid such ISPs in times of degradations. A large number of end-to-end Internet paths are probed and we measure delay, jitter, and loss rates. The measurement data is analyzed offline to identify ways to enable a source to select alternate paths in an overlay network to improve video-QoE, without the need for background monitoring or apriori knowledge of path characteristics. We establish that for any unstructured overlay of N nodes, it is sufficient to reroute key frames using a random subset of k nodes in the overlay, where k is bounded by O(lnN). We analyze various properties of such random subsets to derive simple, scalable, and an efficient path selection strategy that results in a k-fold increase in path options for any source-destination pair; options that consistently outperform Internet path selection. Finally, we design a prototype called source initiated frame restoration (SIFR) that employs random subsets to derive alternate paths and demonstrate its effectiveness in improving Internet video-QoE.
Show less - Date Issued
- 2011
- Identifier
- CFE0004012, ucf:49168
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004012
- Title
- MEASURING MULTILEVEL CONSTRUCTS: THEORETICAL AND METHODOLOGICAL FEATURES OF TEAM BEHAVIORAL PROCESS UNDER COMPILATIONAL MODELS.
- Creator
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Murase, Toshio, Dechurch, Leslie, Salas, Eduardo, Bowers, Clint, Kapucu, Naim, University of Central Florida
- Abstract / Description
-
Since at least the 1950s, researchers interested in studying the dynamics of small groups have struggled with how best to measure interaction processes. Although team process measurement issues are not particularly unique in terms of content, measuring multilevel phenomena presents an interesting problem because structural aspects are integral components of emergence. The elemental content of multilevel phenomena is wholly unique and distinguishable from the elemental content of composite...
Show moreSince at least the 1950s, researchers interested in studying the dynamics of small groups have struggled with how best to measure interaction processes. Although team process measurement issues are not particularly unique in terms of content, measuring multilevel phenomena presents an interesting problem because structural aspects are integral components of emergence. The elemental content of multilevel phenomena is wholly unique and distinguishable from the elemental content of composite units, and emerges as individual behaviors compile to higher levels of analyses. Analogous to chemical structures, behavioral phenomena manifest at higher levels in different structural patterns as members connect to one another through dynamic interactions. Subsequently, multilevel phenomena are more appropriately characterized in terms of pattern in addition to the traditionally measured intensity. The vast majority of teams research conceptualizes and operationalizes multilevel phenomena based on compositional (i.e., additive) models. This approach impedes the further advancement of the science of team effectiveness by capturing content and intensity, but not structure. This dissertation argues that compilational models better capture content, intensity, and structure, and therefore represent a preferred alternative for conceptualizing and operationalizing team processes. This dissertation details measurement issues associated with compositional models in teams research, and provides concepts helpful for reconceptualizing team processes as compilational forms.
Show less - Date Issued
- 2011
- Identifier
- CFE0004145, ucf:49048
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004145
- Title
- KNOWLEDGE MANAGEMENT DETERMINANTS OF CONTINUANCE BEHAVIOR: EVALUATING THE AIR FORCE KNOWLEDGE NOW KNOWLEDGE MANAGEMENT SYSTEM.
- Creator
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Tucker, Eric, Kotnour, Timothy, University of Central Florida
- Abstract / Description
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Knowledge management (KM) encompasses the set of capabilities, processes, tools, and techniques for the most effective use of knowledge by an organization. The goal of KM is to improve the organizationÂÂ's ability to create, transfer, retain, and apply knowledge. Knowledge management is a goal that many organizations seek to achieve. Organizations apply their strategies, plans, and implementation to achieve KM. Organizations use technology to implement their KM strategy...
Show moreKnowledge management (KM) encompasses the set of capabilities, processes, tools, and techniques for the most effective use of knowledge by an organization. The goal of KM is to improve the organizationÂÂ's ability to create, transfer, retain, and apply knowledge. Knowledge management is a goal that many organizations seek to achieve. Organizations apply their strategies, plans, and implementation to achieve KM. Organizations use technology to implement their KM strategy. For some, this approach has worked well; however, for others, the results have fallen short. KM shortcomings revolve around employeesÂÂ' infrequent use of the technology. This research seeks to understand what influences a userÂÂ's behavior to use a KM system and why a user becomes a routine user. This research provides a model of KM continuance behavior and post-acceptance usage behavior. Post-acceptance usage behavior is how an individual decides to use a system after its initial acceptance. The KM continuance model incorporates technology, community, individual, and organizational elements that influence a userÂÂ's intentions and actual use of a KM system. The specific context of this research is a KM system known as the Air Force Knowledge Now (AFKN) system. AFKN emphasizes KM through expertise-sharing activities in Communities of Practice (CoPs). The AFKN KM system facilitates and enhances the relationships in the community. The data for this study were obtained by using an online questionnaire. The results are analyzed using Partial Least Squares structural equation modeling with a two-step data analysis approach. The first step assessed the properties of the measurement model. The second step assessed the path model. Path coefficients and t-values are generated to evaluate the 14 proposed hypotheses. The results of the investigation show that community and technology KM both positively influence a userÂÂ's evaluation of the KM environment. The results produced a coefficient of determination of 60% for KM continued-use intention and 31% for KM continued-use behavior. The outcome of this research is a model that allows organizations to tailor their KM systems efforts to the organizational environment in order to maximize their resources. This investigation serves as a foundation for further research and development in areas of KM, KM systems, and post-acceptance usage.
Show less - Date Issued
- 2010
- Identifier
- CFE0003328, ucf:48484
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003328
- Title
- A DECISION SUPPORT SYSTEM METHODOLOGY FOR THE SELECTION OF RAPID PROTOTYPING TECHNOLOGIES FOR INVESTMENT-CAST GAS TURBINE PARTS.
- Creator
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Gallagher, Angela, Geiger, Christopher, University of Central Florida
- Abstract / Description
-
In the power generation sector, more specifically, the gas turbine industry, competition has forced the lead time-to-market for product advancements to be more important than ever. For design engineers, this means that product design iterations and final product development must be completed within both critical time windows and budgetary constraints. Therefore, two areas that have received significant attention in the research and in practice are: (1) rapid prototyping technology development...
Show moreIn the power generation sector, more specifically, the gas turbine industry, competition has forced the lead time-to-market for product advancements to be more important than ever. For design engineers, this means that product design iterations and final product development must be completed within both critical time windows and budgetary constraints. Therefore, two areas that have received significant attention in the research and in practice are: (1) rapid prototyping technology development, and (2) rapid prototyping technology selection. Rapid prototyping technology selection is the focus of this research. In practice, selecting the rapid prototyping method that is acceptable for a specific design application is a daunting task. With technological advancements in both rapid prototyping and conventional machining methods, it is difficult for both a novice design engineer as well as an experienced design engineer to decide not only what rapid prototyping method could be applicable, but also if a rapid prototyping method would even be advantageous over a more conventional machining method and where in the manufacturing process any of these processes would be utilized. This research proposes an expert system that assists a design engineer through the decision process relating to the investment casting of a superalloy gas turbine engine component. Investment casting is a well-known technique for the production of many superalloy gas turbine parts such as gas turbine blades and vanes. In fact, investment-cast turbine blades remain the state of the art in gas turbine blade design. The proposed automated expert system allows the engineer to effectively assess rapid prototyping opportunities for desired gas turbine blade application. The system serves as a starting point in presenting an engineer with commercially-available state-of-the-art rapid prototyping options, brief explanations of each option and the advantages and disadvantages of each option. It is not intended to suggest an optimal solution as there is not only one unique answer. For instance, cost and time factors vary depending upon the individual needs of a company at any particular time as well as existing strategic partnerships with particular foundries and vendors. The performance of the proposed expert system is assessed using two real-world case studies. The first case study shows how the expert system can advise the design engineer when suggesting rapid manufacturing in place of investment casting. The second case study shows how rapid prototyping can be used for creating part patterns for use within the investment casting process. The results from these case studies are telling in that their implementations potentially result in an 82 to 94% reduction in design decision lead time and a 92 to 97% cost savings.
Show less - Date Issued
- 2010
- Identifier
- CFE0003338, ucf:48469
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003338
- Title
- ALGEBRAIC ASPECTS OF (BIO) NANO-CHEMICAL REACTION NETWORKS AND BIFURCATIONS IN VARIOUS DYNAMICAL SYSTEMS.
- Creator
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Chen, Teng, Brennan, Joseph, University of Central Florida
- Abstract / Description
-
The dynamics of (bio) chemical reaction networks have been studied by different methods. Among these methods, the chemical reaction network theory has been proven to successfully predicate important qualitative properties, such as the existence of the steady state and the asymptotic behavior of the steady state. However, a constructive approach to the steady state locus has not been presented. In this thesis, with the help of toric geometry, we propose a generic strategy towards this question...
Show moreThe dynamics of (bio) chemical reaction networks have been studied by different methods. Among these methods, the chemical reaction network theory has been proven to successfully predicate important qualitative properties, such as the existence of the steady state and the asymptotic behavior of the steady state. However, a constructive approach to the steady state locus has not been presented. In this thesis, with the help of toric geometry, we propose a generic strategy towards this question. This theory is applied to (bio)nano particle con gurations. We also investigate Hopf bifurcation surfaces of various dynamical systems.
Show less - Date Issued
- 2011
- Identifier
- CFE0003933, ucf:48689
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003933
- Title
- A CONTEXTUAL APPROACH TO LEARNING COLLABORATIVE BEHAVIOR VIA OBSERVATION.
- Creator
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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.
Show less - Date Issued
- 2011
- Identifier
- CFE0003602, ucf:48869
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003602
- Title
- IMPROVING THROUGHPUT AND PREDICTABILITY OF HIGH-VOLUME BUSINESS PROCESSES THROUGH EMBEDDED MODELING.
- Creator
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DeKeyrel, Joseph, Malone, Linda, University of Central Florida
- Abstract / Description
-
Being faster is good. Being predictable is better. A faithful model of a system, loaded to reflect the system's current state, can then be used to look into the future and predict performance. Building faithful models of processes with high degrees of uncertainty can be very challenging, especially where this uncertainty exists in terms of processing times, queuing behavior and re-work rates. Within the context of an electronic, multi-tiered workflow management system (WFMS) the author builds...
Show moreBeing faster is good. Being predictable is better. A faithful model of a system, loaded to reflect the system's current state, can then be used to look into the future and predict performance. Building faithful models of processes with high degrees of uncertainty can be very challenging, especially where this uncertainty exists in terms of processing times, queuing behavior and re-work rates. Within the context of an electronic, multi-tiered workflow management system (WFMS) the author builds such a model to endogenously quote due dates. A WFMS that manages business objects can be recast as a flexible flow shop in which the stations that a job (representing the business object) passes through are known and the jobs in the stations queues at any point are known. All of the other parameters associated with the flow shop, including job processing times per station, and station queuing behavior are uncertain though there is a significant body of past performance data that might be brought to bear. The objective, in this environment, is to meet the delivery date promised when the job is accepted. To attack the problem the author develops a novel heuristic algorithm for decomposing the WFMS's event logs exposing non-standard queuing behavior, develops a new simulation component to implement that behavior, and assembles a prototypical system to automate the required historical analysis and allow for on-demand due date quoting through the use of embedded discrete event simulation modeling. The developed software components are flexible enough to allow for both the analysis of past performance in conjunction with the WFMS's event logs, and on-demand analysis of new jobs entering the system. Using the proportion of jobs completed within the predicted interval as the measure of effectiveness, the author validates the performance of the system over six months of historical data and during live operations with both samples achieving the 90% service level targeted.
Show less - Date Issued
- 2011
- Identifier
- CFE0003580, ucf:48913
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003580
- Title
- A Production and Cost Modeling Methodology of 2nd Generation Biofuel in the United States.
- Creator
-
Poole, David, Kincaid, John, Mollaghasemi, Mansooreh, Geiger, Christopher, University of Central Florida
- Abstract / Description
-
The use of biofuels in the United States has increased dramatically in the last few years. The largest source of feedstock for ethanol to date has been corn. However, corn is also a vitally important food crop and is used commonly as feed for cattle and other livestock. To prevent further diversion of an important food crop to production of ethanol, there is great interest in developing commercial-scale technologies to make ethanol from non-food crops, or other suitable plant material. This...
Show moreThe use of biofuels in the United States has increased dramatically in the last few years. The largest source of feedstock for ethanol to date has been corn. However, corn is also a vitally important food crop and is used commonly as feed for cattle and other livestock. To prevent further diversion of an important food crop to production of ethanol, there is great interest in developing commercial-scale technologies to make ethanol from non-food crops, or other suitable plant material. This is commonly referred to as biomass. A review is made of lignocellulosic sources being considered as feedstocks to produce ethanol. Current technologies for pretreatment and hydrolysis of the biomass material are examined and discussed. Production data and cost estimates are culled from the literature, and used to assist in development of mathematical models for evaluation of production ramp-up profiles, and cost estimation. These mathematical models are useful as a planning tool, and provide a methodology to estimate monthly production output and costs for labor, capital, operations and maintenance, feedstock, raw materials, and total cost. Existing credits for ethanol production are also considered and modeled. The production output in liters is modeled as a negative exponential growth curve, with a rate coefficient providing the ability to evaluate slower, or faster, growth in production output and its corresponding effect on monthly cost. The capital and labor costs per unit of product are determined by dividing the monthly debt service and labor costs by that month?s production value. The remaining cost components change at a constant rate in the simulation case studies. This methodology is used to calculate production levels and costs as a function of time for a 25 million gallon per year capacity cellulosic ethanol plant. The parameters of interest are calculated in MATLAB with a deterministic, continuous system simulation model. Simulation results for high, medium, and low cost case studies are included. Assumptions for the model and for each case study are included and some comparisons are made to cost estimates in the literature. While the cost per unit of product decreases and production output increases over time, some reasonable cost values are obtained by the end of the second year for both the low and medium cost case studies. By the end of Year 2, total costs for those case studies are $0.48 per liter and $0.88 per liter, respectively. These cost estimates are well within the reported range of values from the reviewed literature sources. Differing assumptions for calculations made by different sources make a direct cost comparison with the outputs of this modeling methodology extremely difficult. Proposals for reducing costs are introduced. Limitations and shortcomings of the research activity are discussed, along with recommendations for potential future work in improving the simulation model and model verification activities. In summary, the author was not able to find evidence?within the public domain?of any similar modeling and simulation methodology that uses a deterministic, continuous simulation model to evaluate production and costs as a function of time. This methodology is also unique in highlighting the important effect of production ramp-up on monthly costs for capital (debt service) and labor. The resultant simulation model can be used for planning purposes and provides an independent, unbiased estimate of cost as a function of time.
Show less - Date Issued
- 2012
- Identifier
- CFE0004424, ucf:49321
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004424
- Title
- Harmony Oriented Architecture.
- Creator
-
Martin, Kyle, Hua, Kien, Wu, Annie, Heinrich, Mark, University of Central Florida
- Abstract / Description
-
This thesis presents Harmony Oriented Architecture: a novel architectural paradigm that applies the principles of Harmony Oriented Programming to the architecture of scalable and evolvable distributed systems. It is motivated by research on Ultra Large Scale systems that has revealed inherent limitations in human ability to design large-scale software systems that can only be overcome through radical alternatives to traditional object-oriented software engineering practice that simplifies the...
Show moreThis thesis presents Harmony Oriented Architecture: a novel architectural paradigm that applies the principles of Harmony Oriented Programming to the architecture of scalable and evolvable distributed systems. It is motivated by research on Ultra Large Scale systems that has revealed inherent limitations in human ability to design large-scale software systems that can only be overcome through radical alternatives to traditional object-oriented software engineering practice that simplifies the construction of highly scalable and evolvable system.HOP eschews encapsulation and information hiding, the core principles of object- oriented design, in favor of exposure and information sharing through a spatial abstraction. This helps to avoid the brittle interface dependencies that impede the evolution of object-oriented software. HOA extends these concepts to distributed systems resulting in an architecture in which application components are represented by objects in a spatial database and executed in strict isolation using an embedded application server. Application components store their state entirely in the database and interact solely by diffusing data into a space for proximate components to observe. This architecture provides a high degree of decoupling, isolation, and state exposure allowing highly scalable and evolvable applications to be built.A proof-of-concept prototype of a non-distributed HOA middleware platform supporting JavaScript application components is implemented and evaluated. Results show remarkably good performance considering that little effort was made to optimize the implementation.
Show less - Date Issued
- 2011
- Identifier
- CFE0004480, ucf:49298
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004480
- Title
- AUTOMATIC GRAPHICS AND GAME CONTENT GENERATION THROUGH EVOLUTIONARY COMPUTATION.
- Creator
-
Hastings, Erin, Stanley, Kenneth, University of Central Florida
- Abstract / Description
-
Simulation and game content includes the levels, models, textures, items, and other objects encountered and possessed by players during the game. In most modern video games and simulation software, the set of content shipped with the product is static and unchanging, or at best, randomized within a narrow set of parameters. However, ideally, if game content could be constantly and automatically renewed, players would remain engaged longer in the evolving stream of content. This dissertation...
Show moreSimulation and game content includes the levels, models, textures, items, and other objects encountered and possessed by players during the game. In most modern video games and simulation software, the set of content shipped with the product is static and unchanging, or at best, randomized within a narrow set of parameters. However, ideally, if game content could be constantly and automatically renewed, players would remain engaged longer in the evolving stream of content. This dissertation introduces three novel technologies that together realize this ambition. (1) The first, NEAT Particles, is an evolutionary method to enable users to quickly and easily create complex particle effects through a simple interactive evolutionary computation (IEC) interface. That way, particle effects become an evolvable class of content, which is exploited in the remainder of the dissertation. In particular, (2) a new algorithm called content-generating NeuroEvolution of Augmenting Topologies (cgNEAT) is introduced that automatically generates graphical and game content while the game is played, based on the past preferences of the players. Through cgNEAT, the game platform on its own can generate novel content that is designed to satisfy its players. Finally, (3) the Galactic Arms Race (GAR) multiplayer online video game is constructed to demonstrate these techniques working on a real online gaming platform. In GAR, which was made available to the public and playable online, players pilot space ships and fight enemies to acquire unique particle system weapons that are automatically evolved by the cgNEAT algorithm. The resulting study shows that cgNEAT indeed enables players to discover a wide variety of appealing content that is not only novel, but also based on and extended from previous content that they preferred in the past. The implication is that with cgNEAT it is now possible to create applications that generate their own content to satisfy users, potentially significantly reducing the cost of content creation and considerably increasing entertainment value with a constant stream of evolving content.
Show less - Date Issued
- 2009
- Identifier
- CFE0002814, ucf:48143
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002814
- Title
- DELAY MODELING AND LONG-RANGE PREDICTIVE CONTROL OF CZOCHRALSKI GROWTH PROCESS.
- Creator
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Shah, Dhaval, Klemenz, Christine, University of Central Florida
- Abstract / Description
-
This work presents the Czochralski growth dynamics as time-varying delay based model, applied to the growth of La3Ga5.5Ta0.5O14 (LGT) piezoelectric crystals. The growth of high-quality large-diameter oxides by Czochralski technique requires the theoretical understanding and optimization of all relevant process parameters, growth conditions, and melts chemistry. Presently, proportional-integral- derivative (PID) type controllers are widely accepted for constant-diameter crystal growth by...
Show moreThis work presents the Czochralski growth dynamics as time-varying delay based model, applied to the growth of La3Ga5.5Ta0.5O14 (LGT) piezoelectric crystals. The growth of high-quality large-diameter oxides by Czochralski technique requires the theoretical understanding and optimization of all relevant process parameters, growth conditions, and melts chemistry. Presently, proportional-integral- derivative (PID) type controllers are widely accepted for constant-diameter crystal growth by Czochralski. Such control systems, however, do not account for aspects such as the transportation delay of the heat from crucible wall to the crystal solidification front, heat radiated from the crucible wall above the melt surface, and varying melt level. During crystal growth, these time delays play a dominant role, and pose a significant challenge to the control design. In this study, a time varying linear delay model was applied to the identification of nonlinearities of the growth dynamics. Initial results reveled the benefits of this model with actual growth results. These results were used to develop a long-range model predictive control system design. Two different control techniques using long range prediction are studied for the comparative study. Development and testing of the new control system on real time growth system are discussed in detail. The results are promising and suggest future work in this direction. Other discussion about the problems during the crystal growth, optimization of crystal growth parameters are also studied along with the control system design.
Show less - Date Issued
- 2009
- Identifier
- CFE0002581, ucf:48250
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002581
- Title
- CONTROL OF NONHOLONOMIC SYSTEMS.
- Creator
-
Yuan, Hongliang, Qu, Zhihua, University of Central Florida
- Abstract / Description
-
Many real-world electrical and mechanical systems have velocity-dependent constraints in their dynamic models. For example, car-like robots, unmanned aerial vehicles, autonomous underwater vehicles and hopping robots, etc. Most of these systems can be transformed into a chained form, which is considered as a canonical form of these nonholonomic systems. Hence, study of chained systems ensure their wide applicability. This thesis studied the problem of continuous feed-back control of the...
Show moreMany real-world electrical and mechanical systems have velocity-dependent constraints in their dynamic models. For example, car-like robots, unmanned aerial vehicles, autonomous underwater vehicles and hopping robots, etc. Most of these systems can be transformed into a chained form, which is considered as a canonical form of these nonholonomic systems. Hence, study of chained systems ensure their wide applicability. This thesis studied the problem of continuous feed-back control of the chained systems while pursuing inverse optimality and exponential convergence rates, as well as the feed-back stabilization problem under input saturation constraints. These studies are based on global singularity-free state transformations and controls are synthesized from resulting linear systems. Then, the application of optimal motion planning and dynamic tracking control of nonholonomic autonomous underwater vehicles is considered. The obtained trajectories satisfy the boundary conditions and the vehicles' kinematic model, hence it is smooth and feasible. A collision avoidance criteria is set up to handle the dynamic environments. The resulting controls are in closed forms and suitable for real-time implementations. Further, dynamic tracking controls are developed through the Lyapunov second method and back-stepping technique based on a NPS AUV II model. In what follows, the application of cooperative surveillance and formation control of a group of nonholonomic robots is investigated. A designing scheme is proposed to achieves a rigid formation along a circular trajectory or any arbitrary trajectories. The controllers are decentralized and are able to avoid internal and external collisions. Computer simulations are provided to verify the effectiveness of these designs.
Show less - Date Issued
- 2009
- Identifier
- CFE0002683, ucf:48220
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002683
- Title
- DESIGN AND SIMULATION FOR ENCODED PN-OFC SAW SENSOR SYSTEMS.
- Creator
-
Pavlina, John, Malocha, Donald, University of Central Florida
- Abstract / Description
-
Surface acoustic wave (SAW) sensors provide versatility in that they can offer wireless, passive operation in numerous environments. Various SAW device embodiments may also be employed for retrieval of the sensed data. Single sensor systems typically use a single carrier frequency and a simple device embodiment since tagging is not required. However, it is necessary in a multi-sensor environment to both identify the sensor and retrieve the information. Overlapping sensor data signals in time...
Show moreSurface acoustic wave (SAW) sensors provide versatility in that they can offer wireless, passive operation in numerous environments. Various SAW device embodiments may also be employed for retrieval of the sensed data. Single sensor systems typically use a single carrier frequency and a simple device embodiment since tagging is not required. However, it is necessary in a multi-sensor environment to both identify the sensor and retrieve the information. Overlapping sensor data signals in time and frequency present problems when attempting to collect the sensed data at the receiver. This dissertation defines a system simulation environment exclusive to SAW sensors. The major parameters associated with a multi-device system include the transmitter, the channel, and the receiver characteristics. These characteristics are studied for implementation into the simulation environment. A coupling of modes (COM) model for SAW devices is utilized as an accurate software representation of the various SAW devices. Measured device results are presented and compared with COM model predictions to verify performance of devices and system. Several coding techniques to alleviate code collisions and detection errors were investigated and evaluated. These specialized techniques apply the use of time, frequency, and spatial diversity to the devices. Utilizing these multiple-access techniques a multi-device system is realized. An optimal system based on coding technique, frequency of operation, range, and related parameters is presented. Funding for much of this work was provided through STTR contracts from NASA Kennedy Space Center.
Show less - Date Issued
- 2010
- Identifier
- CFE0003124, ucf:48630
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003124
- 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.
Show less - Date Issued
- 2011
- Identifier
- CFE0003722, ucf:48782
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003722
