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Title: ACCELERATED LIFE TESTING OF SUBSEA EQUIPMENT UNDER HYDROSTATIC PRESSURE.
Creator: Thiraviam, Amar Raja, Malone, Linda, University of Central Florida
Abstract / Description: Accelerated Life Testing (ALT) is an effective method of demonstrating and improving product reliability in applications where the products are expected to perform for a long period of time. ALT accelerates a given failure mode by testing at amplified stress level(s) in excess of operational limits. Statistical analysis (parameter estimation) is then performed on the data, based on an acceleration model to make life predictions at use level. The acceleration model thus forms the basis of...
Show moreAccelerated Life Testing (ALT) is an effective method of demonstrating and improving product reliability in applications where the products are expected to perform for a long period of time. ALT accelerates a given failure mode by testing at amplified stress level(s) in excess of operational limits. Statistical analysis (parameter estimation) is then performed on the data, based on an acceleration model to make life predictions at use level. The acceleration model thus forms the basis of accelerated life testing methodology. Well established accelerated models such as the Arrhenius model and the Inverse Power Law (IPL) model exist for key stresses such as temperature and voltage. But there are other stresses like subsea pressure, where there is no clear model of choice. This research proposes a pressure-life (acceleration) model for the first time for life prediction under subsea pressure for key mechanical/physical failure mechanisms. Three independent accelerated tests were conducted and their results analyzed to identify the best model for the pressure-life relationship. The testing included material tests in standard coupons to investigate the effect of subsea pressure on key physical, mechanical, and electrical properties. Tests were also conducted at the component level on critical components that function as a pressure barrier. By comparing the likelihood values of multiple reasonable candidate models for the individual tests, the exponential model was identified as a good model for the pressure-life relationship. In addition to consistently providing good fit among the three tests, the exponential model was also consistent with field data (validation with over 10 years of field data) and demonstrated several characteristics that enable robust life predictions in a variety of scenarios. In addition the research also used the process of Bayesian analysis to incorporate prior information from field and test data to bolster the results and increase the confidence in the predictions from the proposed model.
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Date Issued: 2010
Identifier: CFE0003411, ucf:48422
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0003411

Title: An analytical model for evaluating database update schemes.
Creator: Kinsley, Kathryn C., Hughes, Charles E., Arts and Sciences
Abstract / Description: University of Central Florida College of Arts and Sciences Thesis; A methodology is presented for evaluating the performance of database update schemes. The methodology uses the M/Hr/1 queueing model as a basis for this analysis and makes use of the history of how data is used in the database. Parameters have been introduced which can be set based on the characteristics of a specific system. These include update to retrieval ratio, average file size, overhead, block size and the expected...
Show moreUniversity of Central Florida College of Arts and Sciences Thesis; A methodology is presented for evaluating the performance of database update schemes. The methodology uses the M/Hr/1 queueing model as a basis for this analysis and makes use of the history of how data is used in the database. Parameters have been introduced which can be set based on the characteristics of a specific system. These include update to retrieval ratio, average file size, overhead, block size and the expected number of items in the database. The analysis is specifically directed toward the support of derived data within the relational model. Three support methods are analyzed. These are first examined in a central database system. The analysis is then extended in order to measure performance in a distributed system. Because concurrency is a major problem in a distributive system, the support of derived data is analyzed with respect to three distributive concurrency control techniques -- master/slave, distributed and synchronized. In addition to its use as a performance predictor, the development of the methodology serves to demonstrate how queueing theory may be used to investigate other related database problems. This is an important benefit due to this lack of fundamental results in the area of using queueing theory to analyze database performance.
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Date Issued: 1983
Identifier: CFR0011600, ucf:53041
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0011600

Title: GPU Ray Traced Rendering And Image Fusion Based Visualization Of Urban Terrain For Enhanced Situation Awareness.
Creator: Sik, Lingling, Pattanaik, Sumanta, Kincaid, John, Proctor, Michael, Tappen, Marshall, Graniela Ortiz, Benito, University of Central Florida
Abstract / Description: Urban activities involving planning, preparing for and responding to time critical situations often demands sound situational awareness of overall settings. Decision makers, who are tasked to respond effectively to emergencies, must be equipped with information on the details of what is happening, and must stay informed with updates as the event unfolds and remain attentive to the extent of impact the dynamics of the surrounding settings might have. Recent increases in the volumes of geo...
Show moreUrban activities involving planning, preparing for and responding to time critical situations often demands sound situational awareness of overall settings. Decision makers, who are tasked to respond effectively to emergencies, must be equipped with information on the details of what is happening, and must stay informed with updates as the event unfolds and remain attentive to the extent of impact the dynamics of the surrounding settings might have. Recent increases in the volumes of geo-spatial data such as satellite imageries, elevation maps, street-level photographs and real-time imageries from remote sensory devices affect the way decision makers make assessments in time-critical situations. When terrain related spatial information are presented accurately, timely, and are augmented with terrain analysis such as viewshed computations, enhanced situational understanding could be formed. Painting such enhanced situational pictures, however, demands efficient techniques to process and present volumes of geo-spatial data. Modern Graphics Processing Units (GPUs) have opened up a wide field of applications far beyond processing millions of polygons. This dissertation presents approaches that harness graphics rendering techniques and GPU programmability to visualize urban terrain with accuracy, viewshed analysis and real-time imageries. The GPU ray tracing and image fusion visualization techniques presented herein have the potential to aid in achieving enhanced urban situational awareness and understanding.Current state of the art polygon based terrain representations often use coarse representations for terrain features of less importance to improve rendering rate. This results in reduced geometrical accuracy for selective terrain features that are considered less critical to the visualization or simulation needs. Alternatively, to render highly accurate urban terrain, considerable computational effort is needed. A compromise between achieving real-time rendering rate and accurate terrain representations would have to be made. Likewise, computational tasks involved in terrain-related calculations such as viewshed analysis are highly computational intensive and are traditionally performed at a non-interactive rate. The first contribution of the research involves using GPU ray tracing, a rendering approach, conventionally not employed in the simulation community in favor of rasterization, to achieve accurate visualization and improved understanding of urban terrain. The efficiency of using GPU ray tracing is demonstrated in two areas, namely, in depicting complex, large scale terrain and in visualizing viewshed terrain effects at interactive rate. Another contribution entails designing a novel approach to create an efficient and real-time mapping system. The solution achieves updating and visualizing terrain textures using 2D geo-referenced imageries for enhanced situational awareness. Fusing myriad of multi-view 2D inputs spatially for a complex 3D urban scene typically involves a large number of computationally demanding tasks such as image registrations, mosaickings and texture mapping. Current state of the art solutions essentially belongs to two groups. Each strives to either provide near real-time situational pictures in 2D or off-line complex 3D reconstructions for subsequent usages. The solution proposed in this research relies on using prior constructed synthetic terrains as backdrops to be updated with real-time geo-referenced images. The solution achieves speed in fusing information in 3D. Mapping geo-referenced images spatially in 3D puts them into context. It aids in conveying spatial relationships among the data. Prototypes to evaluate the effectiveness of the aforementioned techniques are also implemented. The benefits of augmenting situational displays with viewshed analysis and real-time geo-referenced images in relation to enhancing the user's situational awareness are also evaluated. Preliminary results from user evaluation studies demonstrate the usefulness of the techniques in enhancing operators' performances, in relation to situational awareness and understanding.
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Date Issued: 2013
Identifier: CFE0005115, ucf:50757
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005115

Title: Effect of Load Path and Failure Modes on Seismic Response of Regular Bridges.
Creator: Darwash, Haider, Mackie, Kevin, Chopra, Manoj, Makris, Nicos, Bai, Yuanli, University of Central Florida
Abstract / Description: Bridges are essential infrastructure constituents that have been studied for centuries. Typically,seismic bridge design and assessment utilize simplified modeling and analysis techniques basedon one-dimensional spine elements and zero-length springs/hinges. The geometry of the elementsand calibration of parameters are based on assumptions for the lateral load path and failure modes,e.g., sacrificial backwall and shear keys, neglecting wing walls, and strength based on backfillalone. These...
Show moreBridges are essential infrastructure constituents that have been studied for centuries. Typically,seismic bridge design and assessment utilize simplified modeling and analysis techniques basedon one-dimensional spine elements and zero-length springs/hinges. The geometry of the elementsand calibration of parameters are based on assumptions for the lateral load path and failure modes,e.g., sacrificial backwall and shear keys, neglecting wing walls, and strength based on backfillalone. These assumptions have led to observations of underestimated resistance, overestimateddisplacement demands, and unpredicted damage and failure mode. The focus of the study is onordinary standard bridges with continuous reinforced concrete box girder superstructures and seattypeabutments.A bridge component calibration study was conducted first using simplified (spine models with 1Delements and springs) and three-dimensional nonlinear continuum finite element models (FEM).Model responses were compared with experimental results to identify the drawbacks in the simplifiedmodels and verify the adequacy of the material nonlinearities and analysis procedures. Thecomponents include a T-girder, abutment backfill, abutment shear key, elastomeric bearing pad,and a bridge pier. Results show the simplified models do not capture damage propagation andfailure mode in the shear key case, nonlinear behaviors in beams with high aspect ratios (or deepbeam action), and underestimate the strength and overestimate the stiffness for the backfill case.The component models (both simplified and continuum) were then used in studying the nonlinearstatic behaviors of key bridge lateral-load resisting substructures, namely abutments and bents.For the abutment subsystem, cases with and without backfill and several back wall constructionjoint configurations for the longitudinal direction, with monolithic shear key and shear key withconstruction joint for the transverse direction, and boundary conditions in the transverse direction were considered. Abutment subsystem results showed simplified models underestimate the resistanceby 10-60%, neglect back wall and wing wall structural contributions, and localize damagein the back fill relative to the continuum models. For the bent subsystem, a full bridge systemthat considers material nonlinearity and damage in the bent segment only was adopted to determinethe effect of the finite bent cap or superstructure-to-column connection. Inelastic behaviorand damage was included in the columns, bent cap, and a superstructure segment with a lengththat correspond to the dead load moment inflection point. The other superstructure segments andthe pile cap were modeled as elastic. Bent subsystem results showed simplified models overestimatethe stiffness, induce excessive flexibility and deformation in the cap beam, and overestimatecolumns' deformations.Due to the differences observed in the abutment subsystem, and the potential impact of the abutmentbehavior on the seismic response of the whole bridge system, dynamic studies on the bridgesystem were conducted using four abutment parameters: abutment stiffness and strength in eachof the longitudinal and transverse directions. Two models were developed to conduct nonlineartime history analysis: an equivalent single-degree-of-freedom (SDOF) model for each of the longitudinaland transverse directions, and a 3D spine bridge model. Constant ductility analyses wereconducted using the SDOF systems, while standard probabilistic seismic demand analysis wasused on the spine systems.Results revealed that, besides the columns yielding, the abutment has an early and significant contributionto the behavior. The SDOF system results showed that increasing the abutment stiffnessor strength reduces the system displacement demand and increases the system forces. The consequenceof such increase in the forces is mobilizing significant amount of force in the abutments,causing inelastic response. The full bridge study also confirmed the SDOF results and showedthat the abutment forces are more than 200% of the columns forces that would result in the sameaftereffect observed in the SDOF system.
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Date Issued: 2017
Identifier: CFE0006869, ucf:51759
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006869

Title: A Complex Calculus: How Message Format and Processing Route Coordinate to Influence HPV Vaccination Message Persuasiveness Among Young Adults.
Creator: Boutemen, Laura, Neuberger, Lindsay, Sellnow, Timothy, Miller, Ann, University of Central Florida
Abstract / Description: Human papillomavirus (HPV) infection may lead to cancer and genital warts yet can be prevented by a safe and effective vaccine recommended for individuals up to 26 years old. HPV vaccination rates remain low among college aged adults that represent a catch-up population still eligible to receive the HPV vaccine. This present study is a theory-based investigation employing the Heuristic Systematic Model to explore the effect of message format and processing route on attitude and behavioral...
Show moreHuman papillomavirus (HPV) infection may lead to cancer and genital warts yet can be prevented by a safe and effective vaccine recommended for individuals up to 26 years old. HPV vaccination rates remain low among college aged adults that represent a catch-up population still eligible to receive the HPV vaccine. This present study is a theory-based investigation employing the Heuristic Systematic Model to explore the effect of message format and processing route on attitude and behavioral intention in the context of HPV vaccination. Undergraduate students aged 17-26 years old (N = 261) from various majors (e.g., STEM, social sciences, humanities) participated in the study. An online message exposure experiment randomly assigned participants one of three messages in different message formats (i.e., accessible, scientific jargon, scientese) promoting HPV vaccination to examine the persuasive potential of clearly worded messages (i.e., accessible message), appropriately used scientific language (i.e., jargon message) and inappropriately used scientific terminology (i.e., scientese message) and the effect of processing route on attitude and behavioral intention pertaining to HPV vaccination. Additionally, the potential impact of scientific literacy was investigated. The three experimental conditions were compared to the control condition that corresponded to no message exposure. Quantitative data analyses revealed the scientese message was associated with higher intention to receive the HPV vaccine than the simply worded message among systematic processors only. Further, systematic processing was related to more favorable attitude toward the message and greater intention to obtain the vaccine. Findings of the current study can help inform future message development to design targeted persuasive messages aiming to encourage vaccination in an effort to augment HPV vaccination rates among the catch-up population.
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Date Issued: 2018
Identifier: CFE0006979, ucf:51658
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0006979

Title: Accelerated Life Model with Various Types of Censored Data.
Creator: Pridemore, Kathryn, Pensky, Marianna, Mikusinski, Piotr, Swanson, Jason, Nickerson, David, University of Central Florida
Abstract / Description: The Accelerated Life Model is one of the most commonly used tools in the analysis of survival data which are frequently encountered in medical research and reliability studies. In these types of studies we often deal with complicated data sets for which we cannot observe the complete data set in practical situations due to censoring. Such difficulties are particularly apparent by the fact that there is little work in statistical literature on the Accelerated Life Model for complicated types...
Show moreThe Accelerated Life Model is one of the most commonly used tools in the analysis of survival data which are frequently encountered in medical research and reliability studies. In these types of studies we often deal with complicated data sets for which we cannot observe the complete data set in practical situations due to censoring. Such difficulties are particularly apparent by the fact that there is little work in statistical literature on the Accelerated Life Model for complicated types of censored data sets, such as doubly censored data, interval censored data, and partly interval censored data.In this work, we use the Weighted Empirical Likelihood approach (Ren, 2001) to construct tests, confidence intervals, and goodness-of-fit tests for the Accelerated Life Model in a unified way for various types of censored data. We also provide algorithms for implementation and present relevant simulation results.I began working on this problem with Dr. Jian-Jian Ren. Upon Dr. Ren's departure from the University of Central Florida I completed this dissertation under the supervision of Dr. Marianna Pensky.
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Date Issued: 2013
Identifier: CFE0004913, ucf:49613
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004913

Title: Identity construction and information processing in a coaching relationship: The effects of coach behavior on coachee goal-setting and commitment.
Creator: Coultas, Christopher, Salas, Eduardo, Salazar, Maritza, Burke, Shawn, Fritzsche, Barbara, University of Central Florida
Abstract / Description: Coaching (professional, business, executive, leadership) has been shown to be effective generally speaking, but questions remain regarding the explanatory mechanisms underlying coaching. I first propose a context-general model that unpacks the sociocognitive dynamics within coaching. The model explains the emergence of different types of coaching relationships, and how the nature of these relationships differentially determine coaching outcomes. Research and theory on social identity...
Show moreCoaching (professional, business, executive, leadership) has been shown to be effective generally speaking, but questions remain regarding the explanatory mechanisms underlying coaching. I first propose a context-general model that unpacks the sociocognitive dynamics within coaching. The model explains the emergence of different types of coaching relationships, and how the nature of these relationships differentially determine coaching outcomes. Research and theory on social identity construction and information processing in dyads provides the foundation upon which I outline a model describing the process and dynamics of coaching identity emergence. Beyond this emergence, my proposed model states that the coachee's understanding of appropriate interpersonal relations and division of labor between coach and coachee (i.e., his/her situated coaching identity or coaching structure schema) should partially dictate the focus and depth of the coachee's information processing during a coaching engagement. Past research has shown information processing to be a key determinant of decision-making and goal commitment, both of which are desirable outcomes within the coaching domain.To explore these issues, I developed a coaching exercise which simulated some of the early aspects of business, leadership, or executive coaching. During this simulation, participants were guided through a process which enabled them to think and talk about their strengths and weaknesses when using different conflict management behaviors. In discussing these aspects of conflict management, participants and coaches (i.e., trained research associates) walked through a supplementary process to facilitate the development of a series of goals (an (")action plan(")) that would enable the participant to improve his or her conflict management behaviors. At the end of the coaching session, participants were asked to what extent they felt committed to the goals they had developed and whether or not they expected them to be efficacious. Throughout the coaching session, participants were also asked at designated break points to report their levels of information processing and their understanding of the coaching structure schema for that particular coaching relationship. The experimental manipulation was presented at the beginning of the session, wherein the coach would explain to the coachee what the ideal nature of coaching should be. These explanations varied in terms of ascribing responsibility and division of labor (-) either to a generic coaching process, to the skill and ability of the coach, to the creativity of the participant, or to the joint interaction between coach and participant. Among other things, I hypothesized that coaching structure schemas that emphasized the participant's role in the coaching process would encourage more information processing, and consequently higher levels of goal commitment. Hypotheses were largely confirmed, showing that information processing and coaching structure schemas are important predictors of goal commitment at the end of one coaching session. The effects of the manipulation were mixed. Claiming behaviors (-) that is, the coach ascribing responsibility for coaching effectiveness to him/herself (-) were only marginally effective in shaping participants' coaching structure schemas. Granting behaviors (-) communicating to the participant that they are responsible for coaching effectiveness (-) were much more effective in facilitating helpful information processing and driving higher levels of goal commitment. One possible explanation for the relative effectiveness of granting over claiming may be that claiming requires a degree of credibility which the coach (again, a trained research associate) had not attained with the participants. Other findings pertain to: (1) the unique variance that independent measures of coach- and coachee-relevant structure schemas contribute to models predicting information processing and goal commitment, (2) the importance of identifying the type or focus of coachee information processing, and (3) the role that psychological mindedness may play in characterizing a more (")coachable(") coachee. Implications include: (1) measuring coachees' coaching structure schemas, (2) intentionally encouraging a more appropriate schema, (3) measuring coachees' psychological mindedness prior to coaching, and (4) dynamically monitoring coachees' schema and their information processing in order to assure better coaching effectiveness. Future researchers should explore ways to enact these implications and also to further explore the theoretical components of these practical implications, such as: (1) measurement methods for better assessing coaching schemas and information processing, (2) what the ideal timings are for different kinds of coaching schemas, and (3) different ways to encourage maximally adaptive and appropriate coaching structure schemas.
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Date Issued: 2014
Identifier: CFE0005319, ucf:50523
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005319

Title: An Examination of the Practice of Instructional Design and the Use of Instructional Design Models.
Creator: Twilley, Jennifer, Gunter, Glenda, Robinson, Edward, Vitale, Thomas, Hayes, Grant, University of Central Florida
Abstract / Description: This dissertation in practice utilized a sequential mixed methods research design to investigate the performance or exclusion of instructional design activities commonly prescribed by instructional design models during a typical instructional design project. The purpose of this study was to compare the performance of instructional design activities by practicing instructional designers with the performance of an experienced instructional designer to determine if instructional design models...
Show moreThis dissertation in practice utilized a sequential mixed methods research design to investigate the performance or exclusion of instructional design activities commonly prescribed by instructional design models during a typical instructional design project. The purpose of this study was to compare the performance of instructional design activities by practicing instructional designers with the performance of an experienced instructional designer to determine if instructional design models are being used to guide the practice of instructional design. In this study, quantitative data was collected from a sample of 224 instructional designers to determine the activities routinely performed and excluded from typical projects. Qualitative data was collected from a single case study of an instructional design project to assess whether or not the performance or exclusion of the same instructional design activities were identified in the work of an experienced instructional designer. Analysis of the data revealed the activities that are not routinely performed by instructional designers, reasons for the exclusion of activities, and possible factors for the decisions to exclude activities.The findings of this study indicate instructional designers may be sacrificing the quality and effectiveness of instruction in an attempt to increase the pace and reduce the cost of the instructional design process. The study concluded that instructional designers are not following the prescriptions of instructional design models during the practice of instructional design by routinely eliminating the fundamental activities involving the development of learner assessments, the performance of formative evaluations during the instructional design process, and summative evaluations after the implementation of the instruction.
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Date Issued: 2014
Identifier: CFE0005432, ucf:50438
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005432

Title: Employing Quality Management Principles to Improve the Performance of Educational Systems: An Empirical Study of the Effect of ISO 9001 Standard on Teachers and Administrators Performance in the Indonesian Vocational Education System.
Creator: Kuncoro, Andreas, Elshennawy, Ahmad, Lee, Gene, Rabelo, Luis, Bai, Haiyan, University of Central Florida
Abstract / Description: ISO 9001 has been world widely implemented in both manufacturing and service organizations. A lot of studies have been conducted to investigate the effects of ISO 9001 implementation on the performance of these organizations. Most of these studies show that ISO 9001 implementation realized positive operational improvements and financial success.Building on the merits of successful implementation of ISO 9001 quality management system in manufacturing and service, educational institutions have...
Show moreISO 9001 has been world widely implemented in both manufacturing and service organizations. A lot of studies have been conducted to investigate the effects of ISO 9001 implementation on the performance of these organizations. Most of these studies show that ISO 9001 implementation realized positive operational improvements and financial success.Building on the merits of successful implementation of ISO 9001 quality management system in manufacturing and service, educational institutions have been attempted to adopt it in their operations. Even though there are studies relating ISO implementation to education, no research has been done to investigate the effects of ISO 9001 at the individual level.The objective of this research is to investigate the effects of ISO 9001 quality management implementation on the performance of administrators and teachers. The Indonesian vocational education system is selected as a case example as there is a significant number of such institutions in Indonesia that attempt to achieve ISO certification and there is a national need to improve the performance of vocational education. It is a challenge to assess objectively the degree of ISO 9001 implementation in this specific educational context because of the size and diversity. This study relies on survey that measures the respondents' perception. Hence, this study applies a self-reported survey based performance measurement. The questionnaires are developed based on extensive literature review. Partial Least Squares Structural Equation Modeling (PLSSEM) has been used to examine the relationships between the different elements of quality management systems, quality culture; administrator and teacher performances. The study is able to examine multiple interrelated dependence and subsequent relationships simultaneously among examined factors such as teacher and administrator performance, existing quality culture and ISO principles; and to incorporate variables that cannot be directly measured, such as leadership, for example. The findings of this study show that ISO 9001 implementation has positive significant effect on the performance of the vocational school administrator and teacher. The study also identifies key influencing elements of the ISO quality management system and examines their direct and indirect relationships with teacher and administrator performances. This study is expected to improve the current practices in implementing ISO and quality culture in any educational settings, specifically in the case of vocational educational system.
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Date Issued: 2013
Identifier: CFE0005019, ucf:50006
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005019

Title: Home Care Quality Effects of Remote Monitoring.
Creator: Williams, Cynthia, Wan, Thomas, Oetjen, Dawn, Burg, Mary Ann, Zhang, Ning, University of Central Florida
Abstract / Description: Despite concerted efforts to decrease costs and increase public health, the embattled U.S. health care system continues to struggle to alleviate these widespread issues. Because the problem of hospital utilizations among patients with heart failure is posited to increase as the population ages, innovative methodologies need to be explored to mitigate adverse events. Remote monitoring harnesses the strength of advanced information and communication technology to affect positive changes in...
Show moreDespite concerted efforts to decrease costs and increase public health, the embattled U.S. health care system continues to struggle to alleviate these widespread issues. Because the problem of hospital utilizations among patients with heart failure is posited to increase as the population ages, innovative methodologies need to be explored to mitigate adverse events. Remote monitoring harnesses the strength of advanced information and communication technology to affect positive changes in health care quality and cost. By reaching across geographical boundaries, remote monitoring may support increased access to less costly services and improve the quality of home health care.The purpose of the study was to examine the home care quality effects of remote monitoring technology in patients with heart failure and to provide an economic justification for its adoption and diffusion. It compared remote monitoring as a potential intervention strategy to a standard no-intervention group (without remote monitoring). Specifically, it analyzed remote monitoring as a viable strategy to decrease hospital readmissions and emergency department visits. It also compared the cost of remote monitoring against the current standard-of-care. The theoretical framework of Donabedian's Quality Model was used in the evaluation of remote monitoring. A retrospective posttest only, case control study design was used to test the degree which remote monitoring was effective in promoting health care quality (hospital readmissions and decreased emergency department visits). Retrospective chart reviews were performed using electronic medical records (EMR). Analysis of Variance, Path Analysis, Automatic Interaction Detector Analysis (Dtreg), and Cost Outcomes Ratio were used to test the hypotheses and validate the proposed theoretical model.No significant difference was noted in remote monitoring and usual care groups. Results suggested that remote monitoring does not statistically lead to a decrease in heart failure-related hospital readmissions and all-cause emergency department visits. Results of the cost ratio analysis suggested that there was no statistically significant difference in the net income between usual care and remote monitoring; however, data suggest that there were significant increases in cost and intensity of nursing utilization for the remote monitoring intervention. The Automatic Interaction Detector Analysis showed that the unfavorable results in hospital readmissions were due to a decrease in collaborative care and patient education prior to the recommendation for hospitalization. The role of nursing care, whether in hospital or community-based care, in heart failure management is critical to quality outcomes. As the field continues to consider the use of technology in health care, decision makers should think through the process of patient care such that preventable hospital readmissions are decreased and patients received quality care.
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Date Issued: 2014
Identifier: CFE0005442, ucf:50383
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0005442

Title: Multi-physics modeling of geomechanical systems with coupled hydromechanical behaviors.
Creator: Mohamed, Ahmad Saeid Ammar, Yun, Hae-Bum, Chopra, Manoj, Sallam, Amr, University of Central Florida
Abstract / Description: Geotechnical structures under realistic field conditions are usually influenced with complex interactions of coupled hydromechanical behavior of porous materials. In many geotechnical applications, however, these important coupled interactions are ignored in their constitutive models. Under coupled hydromechanical behavior, stress in porous materials causes volumetric change in strain, which causes fluid diffusion; consequently, pore pressure dissipates through the pores that results in the...
Show moreGeotechnical structures under realistic field conditions are usually influenced with complex interactions of coupled hydromechanical behavior of porous materials. In many geotechnical applications, however, these important coupled interactions are ignored in their constitutive models. Under coupled hydromechanical behavior, stress in porous materials causes volumetric change in strain, which causes fluid diffusion; consequently, pore pressure dissipates through the pores that results in the consolidation of porous material. The objective of this research was to demonstrate the advantages of using hydromechanical models to estimate deformation and pore water pressure of porous materials by comparing with mechanical-only models. Firstly, extensive literature survey was conducted about hydro-mechanical models based on Biot's poroelastic concept. Derivations of Biot's poroelastic equations will be presented. To demonstrate the hydromechanical effects, a numerical model of poroelastic rock materials was developed using COMSOL, a commercialized multiphysics finite element software package, and compared with the analytical model developed by Wang (2000). Secondly, a series of sensitivity analyses was conducted to correlate the effect of poroelastic parameters on the behavior of porous material. The results of the sensitivity analysis show that porosity and Biot's coefficient has dominant contribution to porous material behavior. Thirdly, a coupled hydromechanical finite element model was developed for a real-world example of embankment consolidation. The simulation results show excellent agreement to field measurements of embankment settlement data.
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Date Issued: 2013
Identifier: CFE0004722, ucf:49826
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0004722

Title: EFFECT OF SOURCE WATER BLENDING ON COPPER RELEASE IN PIPE DISTRIBUTION SYSTEM: THERMODYNAMIC AND EMPIRICAL MODELS.
Creator: Xiao, Weizhong, Taylor, James S., University of Central Florida
Abstract / Description: This dissertation focuses on copper release in drinking water. Qualitative and quantitative assessment of Cu and Fe corrosion by process water quality was assessed over one year in a field study using finished waters produced from seven different treatment process and eighteen pilot distribution systems (PDSs) that were made from unlined cast iron and galvanized steel pipes, and lined cement and PVC pipes taken from actual distribution systems. Totally seven different waters were studied,...
Show moreThis dissertation focuses on copper release in drinking water. Qualitative and quantitative assessment of Cu and Fe corrosion by process water quality was assessed over one year in a field study using finished waters produced from seven different treatment process and eighteen pilot distribution systems (PDSs) that were made from unlined cast iron and galvanized steel pipes, and lined cement and PVC pipes taken from actual distribution systems. Totally seven different waters were studied, which consisted of three source waters: groundwater, surface, and simulated brackish water designated as G1, S1, and RO. With certain pre-established blending ratios, these three waters were blended to form another three waters designated as G2, G3, and G4. Enhanced surface water treatment was CFS, ozonation and GAC filtration, which was designated as S1. The CFS surface water was nanofiltered, which is S2. All seven finished waters were stabilized and chloraminated before entering the PDSs. Corrosion potential was compared qualitatively and quantitatively for all seven waters by monitoring copper and iron release from the PDSs. This dissertation consists of four major parts.(1) Copper corrosion surface characterization in which the solid corrosion products formed in certain period of exposure to drinking water were tried to be identified with kinds of surface techniques. Surface characterization indicated that major corrosion products consists of cuprite (Cu2O) as major underneath corrosion layer and tenorite (CuO), cupric hydroxide (Cu(OH)2) on the top surface. In terms of dissolution/precipitation mechanism controlling the copper concentration in bulk solution, cupric hydroxide thermodynamic model was developed.(2) Theoretical thermodynamic models were developed to predict the copper release level quantitatively based on controlling solid phases identified in part (1). These models are compared to actual data and relative assessment is made of controlling solid phases. (3) Non-linear and linear regression models were developed that accommodated the release to total copper for varying water quality. These models were verified using independent data and provide proactive means of assessing and controlling copper release in a varying water quality environment. (4) Simulation of total copper release was conducted using all possible combinations of water quality produced by blending finished waters from ground, surface and saline sources, which involves the comparison of copper corrosion potentials among reverse osmosis, nanofiltration, enhanced coagulation, lime softening, and conventional drinking water treatment.
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Date Issued: 2004
Identifier: CFE0000042, ucf:46069
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000042

Title: QUANTITATIVE ASSESSMENT OF SOFTWARE DEVELOPMENT PROJECT MANAGEMENT ISSUES USING PROCESS SIMULATION WITH SYSTEM DYNAMICS ELEMENTS.
Creator: Mizell, Carolyn, Malone, Linda, University of Central Florida
Abstract / Description: The complexity of software development projects makes estimation and management very difficult. There is a need for improved cost estimation methods and new models of lifecycle processes other than the common waterfall process. This work has developed a new simulation model of the spiral development lifecycle as well as an approach for using simulation for cost and schedule estimation. The goal is to provide a tool that can analyze the effects of a spiral development process as well as a tool...
Show moreThe complexity of software development projects makes estimation and management very difficult. There is a need for improved cost estimation methods and new models of lifecycle processes other than the common waterfall process. This work has developed a new simulation model of the spiral development lifecycle as well as an approach for using simulation for cost and schedule estimation. The goal is to provide a tool that can analyze the effects of a spiral development process as well as a tool that illustrates the difficulties management faces in forecasting budgets at the beginning of a project which may encourage more realistic approaches to budgetary planning. A new discrete event process model of the incremental spiral development lifecycle approach was developed in order to analyze the effects this development approach has on the estimation process as well as cost and schedule for a project. The input data for the key variables of size, productivity, and defect injection rates in the model was based on analysis of Software Engineering Laboratory data and provided for analysis of the effects of uncertainty in early project estimates. The benefits of combining a separate system dynamics model with a discrete event process models was demonstrated as was the effects of turnover on the cost and schedule for a project. This work includes a major case study of a cancelled NASA software development project that experienced cost and schedule problems throughout its history. Analysis was performed using stochastic simulation with derived probability distributions for key software development factors. A system dynamics model of human resource issues was also combined with the process model to more thoroughly analyze the effects of turnover on a project. This research has demonstrated the benefits of using a simulation model when estimating to allow for more realistic budget and schedule determination including an interval estimate to help focus on the uncertainty of early estimates.
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Date Issued: 2006
Identifier: CFE0001209, ucf:46939
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0001209

Title: HURRICANE EVACUATION: ORIGIN, ROUTE AND DESTINATION.
Creator: Dixit, Vinayak, Radwan, Essam, University of Central Florida
Abstract / Description: Recent natural disasters have highlighted the need to evacuate people as quickly as possible. During hurricane Rita in 2005, people were stuck in queue buildups and large scale congestions, due to improper use of capacity, planning and inadequate response to vehicle breakdown, flooding and accidents. Every minute is precious in situation of such disaster scenarios. Understanding evacuation demand loading is an essential part of any evacuation planning. One of the factors often understood to...
Show moreRecent natural disasters have highlighted the need to evacuate people as quickly as possible. During hurricane Rita in 2005, people were stuck in queue buildups and large scale congestions, due to improper use of capacity, planning and inadequate response to vehicle breakdown, flooding and accidents. Every minute is precious in situation of such disaster scenarios. Understanding evacuation demand loading is an essential part of any evacuation planning. One of the factors often understood to effect evacuation, but not modeled has been the effect of a previous hurricane. This has also been termed as the 'Katrina Effect', where, due to the devastation caused by hurricane Katrina, large number of people decided to evacuate during Hurricane Rita, which hit Texas three weeks after Katrina hit Louisiana. An important aspect influencing the rate of evacuation loading is Evacuation Preparation Time also referred to as 'Mobilization time' in literature. A methodology to model the effect of a recent past hurricane on the mobilization times for evacuees in an evacuation has been presented utilizing simultaneous estimation techniques. The errors for the two simultaneously estimated models were significantly correlated, confirming the idea that a previous hurricane does significantly affect evacuation during a subsequent hurricane. The results show that the home ownership, number of individuals in the household, income levels, and level/risk of surge were significant in the model explaining the mobilization times for the households. Pet ownership and number of kids in the households, known to increase the mobilization times during isolated hurricanes, were not found to be significant in the model. Evacuation operations are marred by unexpected blockages, breakdown of vehicles and sudden flooding of transportation infrastructure. A fast and accurate simulation model to incorporate flexibility into the evacuation planning procedure is required to react to such situations. Presently evacuation guidelines are prepared by the local emergency management, by testing various scenarios utilizing micro-simulation, which is extremely time consuming and do not provide flexibility to evacuation plans. To gain computational speed there is a need to move away from the level of detail of a micro-simulation to more aggregated simulation models. The Cell Transmission Model which is a mesoscopic simulation model is considered, and compared with VISSIM a microscopic simulation model. It was observed that the Cell Transmission Model was significantly faster compared to VISSIM, and was found to be accurate. The Cell Transmission model has a nice linear structure, which is utilized to construct Linear Programming Problems to determine optimal strategies. Optimization models were developed to determine strategies for optimal scheduling of evacuation orders and optimal crossover locations for contraflow operations on freeways. A new strategy termed as 'Dynamic Crossovers Strategy' is proposed to alleviate congestion due to lane blockages (due to vehicle breakdowns, incidents etc.). This research finds that the strategy of implementing dynamic crossovers in the event of lane blockages does improve evacuation operations. The optimization model provides a framework within which optimal strategies are determined quickly, without the need to test multiple scenarios using simulation. Destination networks are the cause of the main bottlenecks for evacuation routes, such aspects of transportation networks are rarely studied as part of evacuation operations. This research studies destination networks from a macroscopic perspective. Various relationships between network level macroscopic variables (Average Flow, Average Density and Average speed) over the network were studied. Utilizing these relationships, a "Network Breathing Strategy" was proposed to improve dissipation of evacuating traffic into the destination networks. The network breathing strategy is a cyclic process of allowing vehicles to enter the network till the network reaches congestion, which is followed by closure of their entry into the network until the network reaches an acceptable state. After which entrance into the network is allowed again. The intuitive motivation behind this methodology is to ensure that the network does not remain in congested conditions. The term 'Network Breathing' was coined due to the analogy seen between this strategy to the process of breathing, where vehicles are inhaled by the network (vehicles allowed in) and dissipated by the network (vehicles are not allowed in). It is shown that the network breathing improves the dissipation of vehicle into the destination network. Evacuation operations can be divided into three main levels: at the origin (region at risk), routes and destination. This research encompasses all the three aspects and proposes a framework to assess the whole system in its entirety. At the Origin the demand dictates when to schedule evacuation orders, it also dictates the capacity required on different routes. These breakthroughs will provide a framework for a real time Decision Support System which will help emergency management official make decisions faster and on the fly.
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Date Issued: 2008
Identifier: CFE0002051, ucf:47589
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002051

Title: MULTIOBJECTIVE COORDINATION MODELS FOR MAINTENANCE AND SERVICE PARTS INVENTORY PLANNING AND CONTROL.
Creator: Martinez, Oscar, Geiger, Christopher, University of Central Florida
Abstract / Description: In many equipment-intensive organizations in the manufacturing, service and particularly the defense sectors, service parts inventories constitute a significant source of tactical and operational costs and consume a significant portion of capital investment. For instance, the Defense Logistics Agency manages about 4 million consumable service parts and provides about 93% of all consumable service parts used by the military services. These items required about US$1.9 billion over the fiscal...
Show moreIn many equipment-intensive organizations in the manufacturing, service and particularly the defense sectors, service parts inventories constitute a significant source of tactical and operational costs and consume a significant portion of capital investment. For instance, the Defense Logistics Agency manages about 4 million consumable service parts and provides about 93% of all consumable service parts used by the military services. These items required about US$1.9 billion over the fiscal years 1999-2002. During the same time, the US General Accountability Office discovered that, in the United States Navy, there were about 3.7 billion ship and submarine parts that were not needed. The Federal Aviation Administration says that 26 million aircraft parts are changed each year. In 2002, the holding cost of service parts for the aviation industry was estimated to be US$50 billion. The US Army Institute of Land Warfare reports that, at the beginning of the 2003 fiscal year, prior to Operation Iraqi Freedom the aviation service parts alone was in excess of US$1 billion. This situation makes the management of these items a very critical tactical and strategic issue that is worthy of further study. The key challenge is to maintain high equipment availability with low service cost (e.g., holding, warehousing, transportation, technicians, overhead, etc.). For instance, despite reporting US$10.5 billion in appropriations spent on purchasing service parts in 2000, the United States Air Force (USAF) continues to report shortages of service parts. The USAF estimates that, if the investment on service parts decreases to about US$5.3 billion, weapons systems availability would range from 73 to 100 percent. Thus, better management of service parts inventories should create opportunities for cost savings caused by the efficient management of these inventories. Unfortunately, service parts belong to a class of inventory that continually makes them difficult to manage. Moreover, it can be said that the general function of service parts inventories is to support maintenance actions; therefore, service parts inventory policies are highly related to the resident maintenance policies. However, the interrelationship between service parts inventory management and maintenance policies is often overlooked, both in practice and in the academic literature, when it comes to optimizing maintenance and service parts inventory policies. Hence, there exists a great divide between maintenance and service parts inventory theory and practice. This research investigation specifically considers the aspect of joint maintenance and service part inventory optimization. We decompose the joint maintenance and service part inventory optimization problem into the supplier's problem and the customer's problem. Long-run expected cost functions for each problem that include the most common maintenance cost parameters and service parts inventory cost parameters are presented. Computational experiments are conducted for a single-supplier two-echelon service parts supply chain configuration varying the number of customers in the network. Lateral transshipments (LTs) of service parts between customers are not allowed. For this configuration, we optimize the cost functions using a traditional, or decoupled, approach, where each supply chain entity optimizes its cost individually, and a joint approach, where the cost objectives of both the supplier and customers are optimized simultaneously. We show that the multiple objective optimization approach outperforms the traditional decoupled optimization approach by generating lower system-wide supply chain network costs. The model formulations are extended by relaxing the assumption of no LTs between customers in the supply chain network. Similar to those for the no LTs configuration, the results for the LTs configuration show that the multiobjective optimization outperforms the decoupled optimization in terms of system-wide cost. Hence, it is economically beneficial to jointly consider all parties within the supply network. Further, we compare the model configurations – LTs versus no LTs, and we show that using LTs improves the overall savings of the system. It is observed that the improvement is mostly derived from reduced shortage costs since the equipment downtime is reduced due to the proximity of the supply. The models and results of this research have significant practical implications as they can be used to assist decision-makers to determine when and where to pre-position parts inventories to maximize equipment availability. Furthermore, these models can assist in the preparation of the terms of long-term service agreements and maintenance contracts between original equipment manufacturers and their customers (i.e., equipment owners and/or operators), including determining the equitable allocation of all system-wide cost savings under the agreement.
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Date Issued: 2008
Identifier: CFE0002459, ucf:47723
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002459

Title: UNIFIED LARGE AND SMALL SIGNAL DISCRETE-SPACE MODELING FOR PWM CONVERTERS IN CCM.
Creator: Shoubaki, Ehab, Batarseh, Issa, University of Central Florida
Abstract / Description: In this Thesis a Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulations of the converter switches , and this approach results in a small signal discrete model. The Second approach is direct and does not involve any approximation of the modulations , this approach yields both a large signal nonlinear discrete model and...
Show moreIn this Thesis a Unified Discrete State-Space Model for power converters in CCM is presented. Two main approaches to arriving at the discrete model are used. The first approach involves an impulse function approximation of the duty cycle modulations of the converter switches , and this approach results in a small signal discrete model. The Second approach is direct and does not involve any approximation of the modulations , this approach yields both a large signal nonlinear discrete model and a linear small signal model. Harmonic analysis of the converter states at steady-state is done for steady-state waveform acquisition , which increases the accuracy of the model especially for finding the control to inductor current frequency response. Finally the Discrete model is verified for the Half-Bridge DC/DC topology for its three main control schemes (Asymmetric , Symmetric , DCS). A GUI platform in MATLAB is presented as a wrapper that utilizes the models and analysis presented in this thesis.
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Date Issued: 2005
Identifier: CFE0000710, ucf:46607
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000710

Title: DIGITAL CONTROL OF HALF-BRIDGE DC-DC CONVERTERS WITH CURRENT DOUBLER RECTIFICATION.
Creator: Yao, Liangbin, Batarseh, Issa, University of Central Florida
Abstract / Description: DC-DC power converters play an important role in powering telecom and computing systems. Complex systems, including power electronics systems, are increasingly using digital controllers because of the major advancements in digital controllers and DSP as well as there ability to perform sophisticated and enhanced control schemes. In this thesis, the digital controller is investigated for DC-DC converters in high current low voltage applications. For an optimal design of a regulated DC-DC...
Show moreDC-DC power converters play an important role in powering telecom and computing systems. Complex systems, including power electronics systems, are increasingly using digital controllers because of the major advancements in digital controllers and DSP as well as there ability to perform sophisticated and enhanced control schemes. In this thesis, the digital controller is investigated for DC-DC converters in high current low voltage applications. For an optimal design of a regulated DC-DC converter, it is necessary to derive a valid model. The current doubler rectified half bridge (CDRHB) DC-DC converter is suitable for high current low voltage applications. In this thesis, the topology operations are analyzed and then the unified state space model, analog small signal model and digital small signal model are derived. Then the digital compensator design is discussed as well as the analog-digital converter (ADC) and the digital pulse-width-modulator (DPWM) design rules. In addition, voltage driving optimization is proposed for the benefit of the digital controller. Finally, experimental results based on the CDRHB are presented and analyzed.
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Date Issued: 2005
Identifier: CFE0000706, ucf:46626
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0000706

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

Title: AN INTEGRATED HYDROLOGY/HYDRAULIC AND WATER QUALITY MODEL FOR WATERSHED-SCALE SIMULATIONS.
Creator: Wang, Cheng, Yeh, Gour-Tsyh, University of Central Florida
Abstract / Description: This dissertation presents the design of an integrated watershed model, WASH123D version 3.0, a first principle, physics-based watershed-scale model of integrated hydrology/hydraulics and water quality transport. This numerical model is comprised of three modules: (1) a one-dimensional (1-D) simulation module that is capable of simulating separated and coupled fluid flow, sediment transport and reaction-based water quality transport in river/stream/canal networks and through control...
Show moreThis dissertation presents the design of an integrated watershed model, WASH123D version 3.0, a first principle, physics-based watershed-scale model of integrated hydrology/hydraulics and water quality transport. This numerical model is comprised of three modules: (1) a one-dimensional (1-D) simulation module that is capable of simulating separated and coupled fluid flow, sediment transport and reaction-based water quality transport in river/stream/canal networks and through control structures; (2) a two-dimensional (2-D) simulation module, capable of simulating separated and coupled fluid flow, sediment transport, and reactive biogeochemical transport and transformation in two-dimensional overland flow systems; and (3) a three-dimensional (3-D) simulation module, capable of simulating separated and coupled fluid flow and reactive geochemical transport and transformation in three-dimensional variably saturated subsurface systems. The Saint Venant equation and its simplified versions, diffusion wave and kinematic wave forms, are employed for surface fluid flow simulations and the modified Richards equation is applied for subsurface flow simulation. The reaction-based advection-dispersion equation is used as the governing equation for water quality transport. Several physically and mathematically based numerical options are provided to solve these governing equations for different application purposes. The surface-subsurface water interactions are considered in the flow module and simulated on the basis of continuity of interface. In the transport simulations, fast/equilibrium reactions are decoupled from slow/kinetic reactions by the decomposition of reaction networks; this enables robust numerical integrations of the governing equation. Kinetic variables are adopted as primary dependent variables rather than biogeochemical species to reduce the number of transport equations and simplify the reaction terms. In each time step, hydrologic/hydraulic variables are solved in the flow module; kinetic variables are then solved in the transport module. This is followed by solving the reactive chemical system node by node to yield concentrations of all species. Application examples are presented to demonstrate the design capability of the model. This model may be of interest to environmental scientists, engineers and decision makers as a comprehensive assessment tool to reliably predict the fluid flow as well as sediment and contaminant transport on watershed scales so as to evaluate the efficacy and impact of alternative watershed management and remediation techniques prior to incurring expense in the field.
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Date Issued: 2009
Identifier: CFE0002947, ucf:47955
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002947

Title: FINDERS KEEPERS: A COMPARATIVE STUDY INVESTIGATING TEACHING THE FLORIDA RESEARCH PROCESS FINDS MODEL THROUGH THREE DIFFERENT APPROACHES AT THE ELEMENTARY SCHOOL LEVEL.
Creator: Serrell, Karen, Beile, Penny, University of Central Florida
Abstract / Description: The children's taunt "Finders Keepers, Losers Weepers" gives new credence to the information search process at the elementary school level. Children keep what they find, claim it as their own, and accept information without discernment or critique. This study examines the effectiveness of teaching information literacy skills through three different approaches. The first curricular approach uses direct instruction to teach children how to do research using the Florida Research Process...
Show moreThe children's taunt "Finders Keepers, Losers Weepers" gives new credence to the information search process at the elementary school level. Children keep what they find, claim it as their own, and accept information without discernment or critique. This study examines the effectiveness of teaching information literacy skills through three different approaches. The first curricular approach uses direct instruction to teach children how to do research using the Florida Research Process FINDS Model. The second approach pairs the FINDS Model with a unit of study that is related to classroom curriculum. The third approach examines the FINDS Model in conjunction with project learning, a constructivist model based on student interest. One hundred twenty- eight third grade students attending a public elementary school in Southwest Florida during the 2008-2009 school year participated in the study. A mixed-methods research approach was used to gather data. Quantitative data was collected with an information literacy pre and post test, and an anonymous media lessons' survey about student preferences. Qualitative data were gathered through a review of student work samples and student interviews. Statistically significant gains were found between the pre to post test scores for all three groups, however no statistically significant differences were found among groups. Although quantitative data did not reveal differences among the treatment groups, qualitative findings revealed that the group taught research skills through the connection to classroom curriculum approach performed better. Thus the findings of this study support existing research which proposes that the best practice for teaching research skills to young children is through a connection to classroom curriculum.
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Date Issued: 2009
Identifier: CFE0002957, ucf:47963
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFE0002957

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