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- Title
- THE RELATIONSHIP BETWEEN THINKING MAPS® AND FLORIDA COMPREHENSIVE ASSESSMENT TEST® READING AND MATHEMATICS SCORES IN TWO URBAN MIDDLE SCHOOLS.
- Creator
-
Diaz, Anna, Martin, Suzanne, University of Central Florida
- Abstract / Description
-
The purpose of this study was to determine what difference, if any, exists between the implementation and use of Thinking Maps® and studentsÂÂ' academic achievement in Reading and Mathematics as measured over time by the Florida Comprehensive Assessment Test® (FCAT). Thinking Maps® is a registered trademark of Thinking Maps, Inc. The data were examined after three years of Thinking MapsÃ&...
Show moreThe purpose of this study was to determine what difference, if any, exists between the implementation and use of Thinking Maps® and studentsÂÂ' academic achievement in Reading and Mathematics as measured over time by the Florida Comprehensive Assessment Test® (FCAT). Thinking Maps® is a registered trademark of Thinking Maps, Inc. The data were examined after three years of Thinking Maps® implementation and instruction. The design of this study was quantitative, with a nonrandomized control group, pretest-posttest design (Ary, Jacobs, & Razavieh, 2002) that examined the effects on student Reading and Mathematics FCAT scores in one middle school that implemented Thinking Maps® throughout all grade levels and core subjects for three years as compared to student Reading and Mathematics FCAT scores in a second middle school that did not implement the Thinking Maps® program throughout all grade levels and core subjects for three years. MANOVA and Chi-square tests were used to examine student FCAT scores. This study focused on one major question: Do students who have been instructed in the use of Thinking Maps® have higher academic achievement as measured by the Florida Comprehensive Assessment Test® (FCAT) than those that have not been instructed in the use of Thinking Maps®? Results of this study indicated that students who have been instructed in the use of Thinking Maps® do not have higher academic achievement as measured by the Florida Comprehensive Assessment Test® (FCAT) than those who have not been instructed in the use of Thinking Maps®. The researcher concluded that other methods of evaluating the implementation of Thinking Maps® and student achievement should be explored.
Show less - Date Issued
- 2010
- Identifier
- CFE0003319, ucf:48448
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003319
- Title
- CURRICULUM CONTROL AND TEACHERS' PERCEPTIONS OF PROFESSIONAL DISCRETION AND SATISFACTION.
- Creator
-
May, Donald, Pawlas, George, University of Central Florida
- Abstract / Description
-
The goal of this research was to investigate teachers' perceptions of professional discretion and satisfaction related to internal and external factors of curriculum control. Results of the study were intended to provide data to policy makers and school district administrators that could be used in the development and implementation of the curriculum reform process. Middle and high school teachers in a large central Florida school district completed the survey. The survey's six...
Show moreThe goal of this research was to investigate teachers' perceptions of professional discretion and satisfaction related to internal and external factors of curriculum control. Results of the study were intended to provide data to policy makers and school district administrators that could be used in the development and implementation of the curriculum reform process. Middle and high school teachers in a large central Florida school district completed the survey. The survey's six constructs were 1. Influence of Teacher Beliefs 2. Perceptions of Success and Satisfaction 3. Influence of Tests and Curriculum Guides 4. Teacher Control of Pedagogy 5. Leadership 6. Maintaining High Standards The research questions focused on determining the difference in perspectives due to years of teaching experience, level of teaching (middle or high school), and curriculum control category (high, medium, or low). The results revealed there was not significant disagreement among teacher perceptions based on years of teaching experience. However, results indicated significant differences in perceptions based on level of teaching and curriculum control category in regard to the six survey constructs. The construct of leadership revealed significant differences between both levels of teaching and curriculum control categories. Overall, the results indicated a significant relationship among curriculum control policies and effects on teachers' perceptions of professional discretion and satisfaction. The literature on curriculum reform efforts since the 1980s, specifically in the areas of curriculum standards, textbook adoption policies, testing policies and leadership practices, framed the study. The literature review focused on existing research issues within the six constructs and the research questions. The information gained from this study may be used to inform policies, improve teachers' working conditions, and promote teacher and leadership effectiveness. Recommendations for practice were addressed in terms of what policy makers, school district administrators, and individual classroom teachers can and should do to implement and support meaningful curriculum reform. The researcher emphasized that recognizing the professional expertise and knowing the perspective of teachers are key to the development and implementation of an effective curriculum reform process.
Show less - Date Issued
- 2010
- Identifier
- CFE0003210, ucf:48572
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003210
- Title
- Mathematical Modeling of Heart Rate Deflection Point in Relation to Respiratory Compensation and Treadmill Running Performance.
- Creator
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Baker, Kayla, Fukuda, David, Hoffman, Jay, Stout, Jeffrey, University of Central Florida
- Abstract / Description
-
Heart rate deflection point (HRDP), identified as the second breakpoint in the (")intensity / heart rate(") relationship, is indicative of the anaerobic threshold (AT). This point can be determined via bi-segmental linear regression (2SEG) or through use of the maximal distance model (D-max); however, the relationship between these methods has yet to be investigated 2. Purpose: To compare the use of 2SEG and D-max methods to determine HRDP and to examine the relationship between these values...
Show moreHeart rate deflection point (HRDP), identified as the second breakpoint in the (")intensity / heart rate(") relationship, is indicative of the anaerobic threshold (AT). This point can be determined via bi-segmental linear regression (2SEG) or through use of the maximal distance model (D-max); however, the relationship between these methods has yet to be investigated 2. Purpose: To compare the use of 2SEG and D-max methods to determine HRDP and to examine the relationship between these values with a metabolic threshold, respiratory compensation point (RCP), as well as running performance [5,000 meter treadmill time trial (5Ktime)]. Methods: Nineteen recreationally active men (n=9, 25.56(&)#177;3.17 y, 1.77(&)#177;0.05 m, 83.52(&)#177;6.77 kg, 48.98(&)#177;7.37 ml(&)#183;kg(&)#183;min-1) and women (n=10, 22.78(&)#177;2.11 y, 1.64(&)#177;0.07 m, 62.28(&)#177;6.20 kg, 42.32(&)#177;4.13 ml(&)#183;kg(&)#183;min-1) were recruited for this study. Participants completed two experimental trials, consisting of a graded exercise test to exhaustion (GXT) and 5,000m time trial on the treadmill. Estimates of HRDP and RCP were calculated from data collected during the GXT. One-way repeated measures analysis of variance was used to compare HRDP found through 2SEG (HRDP2SEG), HRDP found through D-max (HRDPD-max), and RCP. Pearson product moment correlations were used to examine the relationship between variables (HRDP2SEG, HRDPD-max, RCP, and 5Ktime). Results: No differences were found between HRDP2SEG (176.70(&)#177;9.40 bpm), HRDPD-max (178.18(&)#177;6.85 bpm), and RCP (176.92(&)#177;6.63 bpm) (p = 0.533). Strong correlations were found between HRDP2SEG and HRDPD-max (r = 0.831, p (<) 0.0001), RCP and HRDP2SEG (r = 0.650, p = 0.003), and RCP and HRDPD-max (r = 0.619, p = 0.005). No relationship was found between 5Ktime and HRDP2SEG (r = 0.419, p = 0.074), HRDPD-max (r = 0.241, p = 0.321), or RCP (r = 0.193, p = 0.429). Similar limits of agreement were found for all comparisons (HRDP2SEG and RCP, p = 0.070; HRDPD-max and RCP, p = 0.868; HRDP2SEG and HRDPD-max, p = 0.029), however, systematic bias was found between HRDP2SEG and HRDPD-max. Conclusion: Based on these results, HRDP2SEG and HRDPD-max could potentially be used interchangeably as methods to determine HRDP. However, the potential for systematic bias must be taken into consideration. Additionally, the results indicate that RCP and HRDP may provide similar estimates of the anaerobic threshold, but none of these thresholds appear to be related to 5Ktime on a treadmill.
Show less - Date Issued
- 2016
- Identifier
- CFE0006070, ucf:50944
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006070
- Title
- Design Disjunction for Resilient Reconfigurable Hardware.
- Creator
-
Alzahrani, Ahmad, DeMara, Ronald, Yuan, Jiann-Shiun, Lin, Mingjie, Wang, Jun, Turgut, Damla, University of Central Florida
- Abstract / Description
-
Contemporary reconfigurable hardware devices have the capability to achieve high performance, powerefficiency, and adaptability required to meet a wide range of design goals. With scaling challenges facing current complementary metal oxide semiconductor (CMOS), new concepts and methodologies supportingefficient adaptation to handle reliability issues are becoming increasingly prominent. Reconfigurable hardware and their ability to realize self-organization features are expected to play a key...
Show moreContemporary reconfigurable hardware devices have the capability to achieve high performance, powerefficiency, and adaptability required to meet a wide range of design goals. With scaling challenges facing current complementary metal oxide semiconductor (CMOS), new concepts and methodologies supportingefficient adaptation to handle reliability issues are becoming increasingly prominent. Reconfigurable hardware and their ability to realize self-organization features are expected to play a key role in designingfuture dependable hardware architectures. However, the exponential increase in density and complexity of current commercial SRAM-based field-programmable gate arrays (FPGAs) has escalated the overheadassociated with dynamic runtime design adaptation. Traditionally, static modular redundancy techniques areconsidered to surmount this limitation; however, they can incur substantial overheads in both area andpower requirements. To achieve a better trade-off among performance, area, power, and reliability, thisresearch proposes design-time approaches that enable fine selection of redundancy level based on target reliability goals and autonomous adaptation to runtime demands. To achieve this goal, three studies were conducted:First, a graph and set theoretic approach, named Hypergraph-Cover Diversity (HCD), is introduced as a preemptive design technique to shift the dominant costs of resiliency to design-time. In particular, union-freehypergraphs are exploited to partition the reconfigurable resources pool into highly separable subsets ofresources, each of which can be utilized by the same synthesized application netlist. The diverseimplementations provide reconfiguration-based resilience throughout the system lifetime while avoiding thesignificant overheads associated with runtime placement and routing phases. Evaluation on a Motion-JPEGimage compression core using a Xilinx 7-series-based FPGA hardware platform has demonstrated thepotential of the proposed FT method to achieve 37.5% area saving and up to 66% reduction in powerconsumption compared to the frequently-used TMR scheme while providing superior fault tolerance.Second, Design Disjunction based on non-adaptive group testing is developed to realize a low-overheadfault tolerant system capable of handling self-testing and self-recovery using runtime partial reconfiguration.Reconfiguration is guided by resource grouping procedures which employ non-linear measurements given by the constructive property of f-disjunctness to extend runtime resilience to a large fault space and realize a favorable range of tradeoffs. Disjunct designs are created using the mosaic convergence algorithmdeveloped such that at least one configuration in the library evades any occurrence of up to d resource faults, where d is lower-bounded by f. Experimental results for a set of MCNC and ISCAS benchmarks havedemonstrated f-diagnosability at the individual slice level with average isolation resolution of 96.4% (94.4%) for f=1 (f=2) while incurring an average critical path delay impact of only 1.49% and area cost roughly comparable to conventional 2-MR approaches. Finally, the proposed Design Disjunction method is evaluated as a design-time method to improve timing yield in the presence of large random within-die (WID) process variations for application with a moderately high production capacity.
Show less - Date Issued
- 2015
- Identifier
- CFE0006250, ucf:51086
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006250
- Title
- Rethinking Drinking: A Paradigm Shift for Estimating Social and Behavioral Harm.
- Creator
-
Hall, Thomas, Wright, James, Gay, David, Cook, Ida, Dunn, Michael, University of Central Florida
- Abstract / Description
-
This study challenges old saws about negative consequences attributed to alcohol use. Previous research findings associate negative social and behavioral consequences with alcohol consumption, as if college students only do regrettable things when they are drunk. Typical research related to negative consequences and alcohol use relies on retrospective self-reporting. Investigators often frame negative consequences as outcomes of problematic drinking or, as more commonly labeled, "binge...
Show moreThis study challenges old saws about negative consequences attributed to alcohol use. Previous research findings associate negative social and behavioral consequences with alcohol consumption, as if college students only do regrettable things when they are drunk. Typical research related to negative consequences and alcohol use relies on retrospective self-reporting. Investigators often frame negative consequences as outcomes of problematic drinking or, as more commonly labeled, "binge drinking." In the nomenclature of prevention, binge drinking is not a direct measure of alcohol use resulting in intoxication; it is a hypothetical tipping point, predicting an increased likelihood of the incidence of negative consequences at some (often unspecified) point in the path between (")sober(") and (")drunk(").It is obvious that social and behavioral distress and misbehavior are not limited to drinking. Students miss class, express regrets, say or do embarrassing things, and get injured while sober as well as while drinking. Contemporary measures of alcohol-related negative consequences do not typically control for the prevalence of negative consequences when respondents are sober as well as when they are drinking. Thus it is unclear if the association between drinking and negative consequences is exclusively attributable to alcohol consumption, as is frequently assumed. Self-reported alcohol-related negative consequences might reflect a priori attitudes, beliefs, and behaviors and be unrelated to drinking. The prevalence of social complications unassociated with drinking merits investigation. A better understanding of the overall prevalence of negative consequences is needed to test the notion that drinking, binge drinking in particular, leads to numerous negative consequences presently reported in the alcohol studies literature.
Show less - Date Issued
- 2016
- Identifier
- CFE0006112, ucf:51196
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006112
- Title
- A Comparison of Aluminum and Iron-based Coagulants for Treatment of Surface Water in Sarasota County, Florida.
- Creator
-
Yonge, David, Duranceau, Steven, Randall, Andrew, Cooper, Charles, University of Central Florida
- Abstract / Description
-
In this research, five different coagulants were evaluated to determine their effectiveness at removing turbidity, color and dissolved organic carbon (DOC) from a surface water in Sarasota County, Florida. Bench-scale jar tests that simulated conventional coagulation, flocculation, and sedimentation processes were used. Iron-based coagulants (ferric chloride and ferric sulfate) and aluminum-based coagulants (aluminum sulfate, polyaluminum chloride (PACl) and aluminum chlorohydrate (ACH)) were...
Show moreIn this research, five different coagulants were evaluated to determine their effectiveness at removing turbidity, color and dissolved organic carbon (DOC) from a surface water in Sarasota County, Florida. Bench-scale jar tests that simulated conventional coagulation, flocculation, and sedimentation processes were used. Iron-based coagulants (ferric chloride and ferric sulfate) and aluminum-based coagulants (aluminum sulfate, polyaluminum chloride (PACl) and aluminum chlorohydrate (ACH)) were used to treat a highly organic surface water supply (DOC ranging between 10 and 30 mg/L), known as the Cow Pen Slough, located within central Sarasota County, Florida. Isopleths depicting DOC and color removal efficiencies as a function of both pH and coagulant dose were developed and evaluated. Ferric chloride and ACH were observed to obtain the highest DOC (85% and 70%, respectively) and color (98% and 97%, respectively) removals at the lowest dose concentrations (120 mg/L and 100 mg/L, respectively). Ferric sulfate was effective at DOC removal but required a higher concentration of coagulant and was the least effective coagulant at removing color. The traditional iron-based coagulants and alum had low turbidity removals and they were often observed to add turbidity to the water. PACl and ACH had similar percent removals for color and turbidity achieving consistent percent removals of 95% and 45%, respectively, but PACl was less effective than ACH at removing organics. Sludge settling curves, dose-sludge production ratios, and settling velocities were determined at optimum DOC removal conditions for each coagulant. Ferric chloride was found to have the highest sludge settling rate but also produced the largest sludge quantities. Total trihalomethane formation potential (THMFP) was measured for the water treated with ferric chloride and ACH. As with DOC removal, ferric chloride yielded a higher percent reduction with respect to THMFP.
Show less - Date Issued
- 2012
- Identifier
- CFE0004621, ucf:49936
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004621
- Title
- An Examination of School Principals' Moral Reasoning and Decision-Making along the Principalship Track and across Years of Experience.
- Creator
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Ling, Trent, Murray, Barbara, Baldwin, Lee, Murray, Kenneth, Holt, Larry, University of Central Florida
- Abstract / Description
-
Previous research by Vitton (&) Wasonga (2009) and Strenth (2013) found public school K-12 principals struggling in the moral reasoning and decision-making measures of the second Defining Issues Test ((")DIT-2(")). In response to these studies, this research sought to collect, to examine, and to compare DIT-2 data for educational leaders at various stages of the principalship track in an effort to determine and/or to isolate the locus of principals' reported underperformance. The moral...
Show morePrevious research by Vitton (&) Wasonga (2009) and Strenth (2013) found public school K-12 principals struggling in the moral reasoning and decision-making measures of the second Defining Issues Test ((")DIT-2(")). In response to these studies, this research sought to collect, to examine, and to compare DIT-2 data for educational leaders at various stages of the principalship track in an effort to determine and/or to isolate the locus of principals' reported underperformance. The moral reasoning and decision-making of regular-education K-12 public school principals and assistant principals in Florida, and current master's degree students in educational leadership programs at a large public Florida university were measured and compared. Research questions were posed: 1) to find the levels of moral reasoning and decision-making reached by acting principals, acting assistant principals, and current master's students in educational leadership programs; 2) to determine if there was a difference between these principals, assistant principals, and master's students in moral reasoning and decision-making; and 3) to see if there was a difference in moral reasoning and decision-making between principals across various years of experience. The DIT-2 was administered anonymously to participants through an online link, and was scored by the University of Alabama's Office for the Study of Ethical Development. Data were analyzed through descriptive and inferential statistical methods principally to determine the degree to which participants reasoned and made decisions based upon personal interests, upon the maintenance of norms, or upon the basis of more sophisticated principles.Results showed master's students in educational leadership outperforming active principals and assistant principals in moral reasoning and decision-making by more often employing sophisticated principles and by more often avoiding choices associated with personal interests. With regard to principals, the difference was statistically significant on DIT-2 N-2 scores (based on ANOVA and t-test results) and P-scores (based on t-test results, but not based on ANOVA results). Principals not only underperformed master's students in educational leadership statistically significantly, but also underperformed active assistant principals in comparisons of group means on DIT-2 sub-scores.This research confirms the prior works of Strenth (2013) and Vitton (&) Wasonga (2009), where principals had been found to struggle in measures of moral reasoning and decision-making. These consecutive and consistent findings now require consideration, discussion, and action by the array of K-12 public school stakeholders. In response to the startling findings that K-12 principals are significantly underperforming those still aspiring for the principalship, a substantial, alarmed, and sober re-examination must take place as to what has happened to principals in K-12 public schools, and as to what can and must be done about it.
Show less - Date Issued
- 2014
- Identifier
- CFE0005368, ucf:50485
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0005368
- Title
- A COMPARISON OF EIGHTH GRADE READING SCORES BY STATEAND BY THE FOUR CENSUS-DEFINED REGIONS IDENTIFIED BY NAEP.
- Creator
-
Gordon II, William, Taylor, Rosemarye, University of Central Florida
- Abstract / Description
-
This study provided information for policymakers and practitioners by comparing performance of eighth grade students in 2007 on state standardized reading assessments and by the four census-defined regions identified by NAEP. NCLB required states to set their own performance standards and to create their own data collection instruments resulting in increased transparency of student performance data and a lack of uniform accountability systems. The inability of educators, policy-makers, and...
Show moreThis study provided information for policymakers and practitioners by comparing performance of eighth grade students in 2007 on state standardized reading assessments and by the four census-defined regions identified by NAEP. NCLB required states to set their own performance standards and to create their own data collection instruments resulting in increased transparency of student performance data and a lack of uniform accountability systems. The inability of educators, policy-makers, and the general public to make state-by-state comparisons in the area of reading was the catalyst for the study. NAEP data were collected from NCES and state performance data were collected from the USDOE SY 2006-2007 CSPR to determine if a relationship existed between eighth grade students' state scores and NAEP scores in the four census-defined regions. Data were further disaggregated by low socioeconomic students and by nonwhite students. A regression analysis was statistically significant in predicting: a) the state proficient and above scores from the NAEP proficient and above scores, b) the low socioeconomic state proficient and above scores from the NAEP proficient and above scores in the West census-defined region, and c) the nonwhite state proficient and above scores from the NAEP proficient and above scores in all regions. A regression analysis was not statistically significant in predicting low socioeconomic state proficient and above scores from the low socioeconomic NAEP proficient and above scores in the Midwest, South and Northeast regions.
Show less - Date Issued
- 2009
- Identifier
- CFE0002536, ucf:52846
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002536
- Title
- THE RELATIONSHIP OF 10TH-GRADE DISTRICT PROGRESS MONITORING ASSESSMENT SCORES TO FLORIDA COMPREHENSIVE ASSESSMENT TEST SCORES IN READING AND MATHEMATICS FOR 2008-2009.
- Creator
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Underwood, Marilyn, Taylor, Rosemarye, University of Central Florida
- Abstract / Description
-
The focus of this research was to investigate the use of a district created formative benchmark assessment in reading to predict student achievement for 10th-grade students on the Florida Comprehensive Assessment Test (FCAT) in one county in north central Florida. The purpose of the study was to provide information to high school principals and teachers to better understand how students were performing and learning and to maximize use of the formative district benchmark assessment in order to...
Show moreThe focus of this research was to investigate the use of a district created formative benchmark assessment in reading to predict student achievement for 10th-grade students on the Florida Comprehensive Assessment Test (FCAT) in one county in north central Florida. The purpose of the study was to provide information to high school principals and teachers to better understand how students were performing and learning and to maximize use of the formative district benchmark assessment in order to modify instruction and positively impact student achievement. This study expanded a prior limited study which correlated district benchmark assessment scores to FCAT scores for students in grades three through five in five elementary schools in the targeted county. The high correlations suggested further study. This research focused on secondary reading, specifically in 10th grade where both state and targeted county FCAT scores were low in years preceding this research. Investigated were (a) the district formative assessment in reading as a predictor of FCAT Reading scores, (b) differences in strength of correlation and prediction among student subgroups and between high schools, and (c) any relationships between reading formative assessment scores and Mathematics FCAT scores. An additional focus of this study was to determine best leadership practices in schools where there were the highest correlations between the formative assessment and FCAT Reading scores. Research on best practices was reviewed, and principals were interviewed to determine trends and themes in practice. Tenth grade students in the seven Florida targeted district high schools were included in the study. The findings of the study supported the effective use of formative assessments both in instruction and as predictors of studentsÂÂÂÂÂÂ' performance on the FCAT. The results of the study also showed a significant correlation between performance on the reading formative assessment and performance on FCAT Mathematics. The data indicated no significant differences in the strength of correlation between student subgroups or between the high schools included in the study. Additionally, the practices of effective principals in using formative assessment data to inform instruction, gathered through personal interviews, were documented and described.
Show less - Date Issued
- 2010
- Identifier
- CFE0003214, ucf:48573
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003214
- Title
- APPLICATION OF THE EMPIRICAL LIKELIHOOD METHOD IN PROPORTIONAL HAZARDS MODEL.
- Creator
-
HE, BIN, Ren, Jian-Jian, University of Central Florida
- Abstract / Description
-
In survival analysis, proportional hazards model is the most commonly used and the Cox model is the most popular. These models are developed to facilitate statistical analysis frequently encountered in medical research or reliability studies. In analyzing real data sets, checking the validity of the model assumptions is a key component. However, the presence of complicated types of censoring such as double censoring and partly interval-censoring in survival data makes model assessment...
Show moreIn survival analysis, proportional hazards model is the most commonly used and the Cox model is the most popular. These models are developed to facilitate statistical analysis frequently encountered in medical research or reliability studies. In analyzing real data sets, checking the validity of the model assumptions is a key component. However, the presence of complicated types of censoring such as double censoring and partly interval-censoring in survival data makes model assessment difficult, and the existing tests for goodness-of-fit do not have direct extension to these complicated types of censored data. In this work, we use empirical likelihood (Owen, 1988) approach to construct goodness-of-fit test and provide estimates for the Cox model with various types of censored data.Specifically, the problems under consideration are the two-sample Cox model and stratified Cox model with right censored data, doubly censored data and partly interval-censored data. Related computational issues are discussed, and some simulation results are presented. The procedures developed in the work are applied to several real data sets with some discussion.
Show less - Date Issued
- 2006
- Identifier
- CFE0001099, ucf:46780
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001099
- Title
- Effluent Water Quality Improvement Using Silt Fences and Stormwater Harvesting.
- Creator
-
Gogo-Abite, Ikiensinma, Chopra, Manoj, Wanielista, Martin, Nam, Boo Hyun, Weishampel, John, University of Central Florida
- Abstract / Description
-
Construction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and...
Show moreConstruction sites are among the most common areas to experience soil erosion and sediment transport due to the mandatory foundation tasks such as excavation and land grubbing. Thus, temporary sediment barriers are installed along the perimeter to prevent sediment transport from the site. Erosion and sediment transport control measures may include, but not limited to, physical and chemical processes such as the use of a silt fence and polyacrylamide product. Runoff from construction sites and other impervious surfaces are routinely discharged into ponds for treatment before being released into a receiving water body. Stormwater harvesting from a pond for irrigation of adjacent lands is promoted as one approach to reducing pond discharge while supplementing valuable potable water used for irrigation. The reduction of pond discharge reduces the mass of pollutants in the discharge. In the dissertation, presented is the investigation of the effectiveness of temporary sediment barriers and then, development of a modeling approach to a stormwater harvesting pond to provide a comprehensive stormwater management pollution reduction assessment tool.The first part of the research presents the investigation of the performance efficiencies of silt fence fabrics in turbidity and sediment concentration removal, and the determination of flow-through-rate on simulated construction sites in real time. Two silt fence fabrics, (1) woven and the other (2) nonwoven were subjected to material index property tests and a series of field-scale tests with different rainfall intensities and events for different embankment slopes on a tilting test-bed. Collected influent and effluent samples were analyzed for sediment concentration and turbidity, and the flow-through-rate for each fabric was evaluated. Test results revealed that the woven and nonwoven silt fence achieved 11 and 56 percent average turbidity reduction efficiency, respectively. Each fabric also achieved 20 and 56 percent average sediment concentration removal efficiency, respectively. Fabric flow-through-rates were functions of the rainfall intensity and embankment slope. The nonwoven fabric exhibited higher flow-through-rates than the woven fabric in both field-scale and laboratory tests.In the second part of the study, a Stormwater Harvesting and Assessment for Reduction of Pollution (SHARP) model was developed to predict operation of wet pond used for stormwater harvesting. The model integrates the interaction of surface water and groundwater in a catchment area. The SHARP model was calibrated and validated with actual pond water elevation data from a stormwater pond at Miramar Lakes, Miramar, Florida. Model evaluation showed adequate prediction of pond water elevation with root mean square error between 0.07 and 0.12 m; mean absolute error was between 0.018 and 0.07 m; and relative index of agreement was between 0.74 and 0.98 for both calibration and validation periods. The SHARP model is capable of assessing harvesting safe-yield and discharge from a pond, including the prediction of the percentage of runoff into a harvesting pond that is not discharged.The combination of silt fence and/or polyacrylamide PAM before stormwater harvesting pond in a treatment train for the reduction of pollutants from construction sites has the potential of significantly exceeding a performance standard of 85 percent reduction typically required by local authorities. In fact, the stringent requirement of equaling pre- and post-development pollutant loading is highly achievable by the treatment train approach. The significant contribution from the integration of the SHARP model to the treatment train is that real-time assessment of pollutant loading reduction by volume can be planned and controlled to achieve target performance standards.
Show less - Date Issued
- 2012
- Identifier
- CFE0004539, ucf:49244
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004539
- Title
- FILM COOLING WITH WAKE PASSING APPLIED TO AN ANNULAR ENDWALL.
- Creator
-
Tran, Nghia, Kapat, Jayanta, University of Central Florida
- Abstract / Description
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Advancement in turbine technology has far reaching effects on today's society and environment. With more than 90% of electricity and 100% of commercial air transport being produced by the usage of gas turbine, any advancement in turbine technology can have an impact on fuel used, pollutants and carbon dioxide emitted to the environment. Within the turbine engine, fully understanding film cooling is critical to reliability of a turbine engine. Film cooling is an efficient way to protect...
Show moreAdvancement in turbine technology has far reaching effects on today's society and environment. With more than 90% of electricity and 100% of commercial air transport being produced by the usage of gas turbine, any advancement in turbine technology can have an impact on fuel used, pollutants and carbon dioxide emitted to the environment. Within the turbine engine, fully understanding film cooling is critical to reliability of a turbine engine. Film cooling is an efficient way to protect the engine surface from the extremely hot incoming gas, which is at a temperature much higher than allowable temperature of even the most advanced super alloy used in turbine. Film cooling performance is affected by many factors: geometrical factors and as well as flow conditions. In most of the film cooling literature, film effectiveness has been used as criterion to judge and/or compare between film cooling designs. Film uniformity is also a critical factor, since it determines how well the coolant spread out downstream to protect the hot-gas-path surface of a gas turbine engine. Even after consideration of all geometrical factors and flow conditions, the film effectiveness is still affected by the stator-rotor interaction, in particular by the moving wakes produced by upstream airfoils. A complete analysis of end wall film cooling inside turbine is required to fully understand the phenomena. This full analysis is almost impossible in the academic arena. Therefore, a simplified but critical experimental rig and computational fluid model were designed to capture the effect of wake on film cooling inside an annular test section. The moving wakes are created by rotating a wheel with 12 spokes or rods with a variable speed motor. Thus changing the motor speed will alter the wake passing frequency. This design is an advancement over most previous studies in rectangular duct, which cannot simulate wakes in an annular passage as in an engine. This rig also includes film injection that allows study of impact of moving wakes on film cooling. This wake is a simplified representation of the trailing edge created by an upstream airfoil. An annulus with 30° pitch test section is considered in this study. This experimental rig is based on an existing flat plate film cooling (BFC) rig that has been validated in the past. Measurement of velocity profiles within the moving wake downstream from the wake generator is used to validate the CFD rotating wake model. The open literature on film cooling and past experiments performed in the laboratory validated the CFD film cooling model. With these validations completed, the full CFD model predicts the wake and film cooling interaction. Nine CFD cases were considered by varying the film cooling blowing ratio and the wake Strouhal number. The results indicated that wakes highly enhance film cooling effectiveness near film cooling holes and degrades the film blanket downstream of the film injection, at the moment of wake passing. However, the time-averaged film cooling effectiveness is more or less the same with or without wake.
Show less - Date Issued
- 2010
- Identifier
- CFE0003483, ucf:48956
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0003483
- Title
- The Impact of using a Computer Algebra System in High School Calculus on High Performing Students' Conceptual and Procedural Understanding.
- Creator
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Bawatneh, Zyad, Haciomeroglu, Erhan, Dixon, Juli, Ortiz, Enrique, Saleh, Suha, University of Central Florida
- Abstract / Description
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Recently, there has been an increasing interest in high school mathematics education, especially in the teaching and learning of calculus. For example, studies conducted by Bressoud (2010); Judson and Nishimori (2005); Koh and Divaharan (2011); and St. Jarre (2008) all looked at how to improve the understanding of calculus students and what roles the educator must take to ensure that their students are successful. The purpose of this study was to determine if there was a significant...
Show moreRecently, there has been an increasing interest in high school mathematics education, especially in the teaching and learning of calculus. For example, studies conducted by Bressoud (2010); Judson and Nishimori (2005); Koh and Divaharan (2011); and St. Jarre (2008) all looked at how to improve the understanding of calculus students and what roles the educator must take to ensure that their students are successful. The purpose of this study was to determine if there was a significant difference between instruction using computer algebra system (CAS) compared to instruction using the graphing calculator in high school calculus on students' conceptual and procedural understanding. This study explored and compared two different types of instruction based on the use of two different types of technology, CAS and graphing calculator. The total population for this study consisted of 333 students. There were 187 students classified as using the graphing calculator and 146 students classified as using CAS. The data for this study were collected from four Advanced Placement (AP) calculus AB courses from high schools in Florida. The study used observations and two sets of calculus tasks in order to gather data. The research questions for this study looked at comparing the grades of students categorized based on the type of instruction received during the learning of calculus. The statistical procedure that was used was a simple one-way analysis of variance (ANOVA). The results indicated that there was no significant difference between the two types of instruction on the students' procedural knowledge, however, there was statistical significance on the students' conceptual understanding in favor of the CAS students. The study introduces a framework on how to obtain information about the effects of different types of instruction on students' understanding of calculus. The results of this study contribute in assisting teachers and future researchers on how to analyze student work in order to obtain information about the students' conceptual and procedural understanding of first semester calculus.
Show less - Date Issued
- 2012
- Identifier
- CFE0004514, ucf:49278
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004514
- Title
- The Relationship Between Reading Coaches' Utilization of Data Technology and Teacher Development.
- Creator
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Behrens, Cherie, Blair, Timothy, Taylor, Rosemarye, Kelley, Michelle, Cartwright, Vickie, Flanigan, Jacquelyn, University of Central Florida
- Abstract / Description
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The use of technology in assisting educators to use student data in well-devised ways to enhance the instruction received by students is gaining headway and the support of federal dollars across the nation. Since research has not provided insight as to whether or not reading coaches are using data technology tools with teachers, this mixed methods study sought to examine what behavioral intentions reading coaches have in using data technology tools with teachers, what variables may influence...
Show moreThe use of technology in assisting educators to use student data in well-devised ways to enhance the instruction received by students is gaining headway and the support of federal dollars across the nation. Since research has not provided insight as to whether or not reading coaches are using data technology tools with teachers, this mixed methods study sought to examine what behavioral intentions reading coaches have in using data technology tools with teachers, what variables may influence their behavioral intentions, and what trends may emerge in their views about using technology data tools with teachers. A mixed methods approach was deployed via a survey embedded in an email, and data from 61 Florida reading coaches from elementary, middle, and high schools in a large urban school district were examined using an adaptation of the Technology Acceptance Model (TAM). The results showed that collectively all reading coaches have a high level of behavioral intentions towards using a data technology tool with teachers. The study also showed that elementary, middle, and high school reading coaches vary in their degree of behavioral intentions in using a data technology tool based on different variables. Trends in data showed that reading coaches think data technology tools are helpful, but that trainings are needed and that technology tools should be user-friendly. Discussion is provided regarding the implications of the study results for all stakeholders.
Show less - Date Issued
- 2012
- Identifier
- CFE0004357, ucf:49425
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004357
- Title
- The Behavior of Cerium Oxide Nanoparticles in Polymer Electrolyte Membranes in Ex-Situ and In-Situ Fuel Cell Durability Tests.
- Creator
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Pearman, Benjamin, Hampton, Michael, Blair, Richard, Clausen, Christian, Seal, Sudipta, Campiglia, Andres, Yestrebsky, Cherie, Mohajeri, Nahid, University of Central Florida
- Abstract / Description
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Fuel cells are known for their high efficiency and have the potential to become a major technology for producing clean energy, especially when the fuel, e.g. hydrogen, is produced from renewable energy sources such as wind or solar. Currently, the two main obstacles to wide-spread commercialization are their high cost and the short operational lifetime of certain components.Polymer electrolyte membrane (PEM) fuel cells have been a focus of attention in recent years, due to their use of...
Show moreFuel cells are known for their high efficiency and have the potential to become a major technology for producing clean energy, especially when the fuel, e.g. hydrogen, is produced from renewable energy sources such as wind or solar. Currently, the two main obstacles to wide-spread commercialization are their high cost and the short operational lifetime of certain components.Polymer electrolyte membrane (PEM) fuel cells have been a focus of attention in recent years, due to their use of hydrogen as a fuel, their comparatively low operating temperature and flexibility for use in both stationary and portable (automotive) applications.Perfluorosulfonic acid membranes are the leading ionomers for use in PEM hydrogen fuel cells. They combine essential qualities, such as high mechanical and thermal stability, with high proton conductivity. However, they are expensive and currently show insufficient chemical stability towards radicals formed during fuel cell operation, resulting in degradation that leads to premature failure. The incorporation of durability improving additives into perfluorosulfonic acid membranes is discussed in this work.Cerium oxide (ceria) is a well-known radical scavenger that has been used in the biological and medical field. It is able to quench radicals by facilely switching between its Ce(III) and Ce(IV) oxidation states.In this work, cerium oxide nanoparticles were added to perfluorosulfonic acid membranes and subjected to ex-situ and in-situ accelerated durability tests.The two ceria formulations, an in-house synthesized and commercially available material, were found to consist of crystalline particles of 2 (-) 5 nm and 20 (-) 150 nm size, respectively, that did not change size or shape when incorporated into the membranes.At higher temperature and relative humidity in gas flowing conditions, ceria in membranes is found to be reduced to its ionic form by virtue of the acidic environment. In ex-situ Fenton testing, the inclusion of ceria into membranes reduced the emission of fluoride, a strong indicator of degradation, by an order of magnitude with both liquid and gaseous hydrogen peroxide. In open-circuit voltage (OCV) hold fuel cell testing, ceria improved durability, as measured by several parameters such as OCV decay rate, fluoride emission and cell performance, over several hundred hours and influenced the formation of the platinum band typically found after durability testing.
Show less - Date Issued
- 2012
- Identifier
- CFE0004789, ucf:49731
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004789
- Title
- Middle Grades Science in Florida: A Comparison of Student Achievement in Comprehensive and Subject-specific Science Courses 2013-2017.
- Creator
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Moore, Kenneth, Taylor, Rosemarye, Baldwin, Lee, Storey, Valerie A., Gao, Su, University of Central Florida
- Abstract / Description
-
As with U.S. student achievement on national and international science assessments, Florida's 8th grade student achievement on the 2013(-)2017 8th grade Florida Comprehensive Assessment Test (FCAT) 2.0 Science/Statewide Science Assessment (SSA) was stagnant. To break this stagnation, many Florida school districts have changed middle grades science course offerings from traditional, subject-specific, discipline-based, layered, or field-specific science courses to comprehensive, integrated,...
Show moreAs with U.S. student achievement on national and international science assessments, Florida's 8th grade student achievement on the 2013(-)2017 8th grade Florida Comprehensive Assessment Test (FCAT) 2.0 Science/Statewide Science Assessment (SSA) was stagnant. To break this stagnation, many Florida school districts have changed middle grades science course offerings from traditional, subject-specific, discipline-based, layered, or field-specific science courses to comprehensive, integrated, spiraled, interdisciplinary, multidisciplinary, thematic, or general science courses. There was a lack of research showing if either type of science course improved student achievement on standardized science assessments. Controlling for school district student population, low socio-economic status (SES) student percentage, and English learner (EL) percentage, this study compared the 2013(-)2017 8th grade FCAT 2.0 Science/SSA school district mean scale scores of two groups of school districts: those that offered comprehensive science courses and those that offered subject-specific science courses. Scores for three student groups were analyzed: all students, low SES students, and ELs. No statistically significant differences were found in school district mean scale scores or pass rates between the two school district groups. The comprehensive group mean scale scores were numerically higher, while the subject-specific group mean pass rates were numerically higher. The subject-specific group had statistically significantly higher raw scores for life science and physical science. The comprehensive group had wider dispersions of mean scale scores and pass rates, suggesting inconsistencies in implementation of comprehensive science courses. The primary implication of this study is that educational leaders should not expect to improve student science achievement simply by changing the type of science course offering. Changes should be made with consideration to student needs, school district demographics, teacher professional development and support, course structure and coherence with standards, and the need for flexibility in teacher assignments.
Show less - Date Issued
- 2018
- Identifier
- CFE0007410, ucf:52710
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007410
- Title
- Factors Affecting Systems Engineering Rigor in Launch Vehicle Organizations.
- Creator
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Gibson, Denton, Karwowski, Waldemar, Rabelo, Luis, Kotnour, Timothy, Kern, David, University of Central Florida
- Abstract / Description
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Systems engineering is a methodical multi-disciplinary approach to design, build, and operate complex systems. Launch vehicles are considered by many extremely complex systems that have greatly impacted where the systems engineering industry is today. Launch vehicles are used to transport payloads from the ground to a location in space. Satellites launched by launch vehicles can range from commercial communications to national security payloads. Satellite costs can range from a few million...
Show moreSystems engineering is a methodical multi-disciplinary approach to design, build, and operate complex systems. Launch vehicles are considered by many extremely complex systems that have greatly impacted where the systems engineering industry is today. Launch vehicles are used to transport payloads from the ground to a location in space. Satellites launched by launch vehicles can range from commercial communications to national security payloads. Satellite costs can range from a few million dollars to billions of dollars. Prior research suggests that lack of systems engineering rigor as one of the leading contributors to launch vehicle failures. A launch vehicle failure could have economic, societal, scientific, and national security impacts. This is why it is critical to understand the factors that affect systems engineering rigor in U.S. launch vehicle organizations.The current research examined organizational factors that influence systems engineering rigor in launch vehicle organizations. This study examined the effects of the factors of systems engineering culture and systems engineering support on systems engineering rigor. Particularly, the effects of top management support, organizational commitment, systems engineering support, and value of systems engineering were examined. This research study also analyzed the mediating role of systems engineering support between top management support and systems engineering rigor, as well as between organizational commitment and systems engineering rigor. A quantitative approach was used for this. Data for the study was collected via survey instrument. A total of 203 people in various systems engineering roles in launch vehicle organizations throughout the United States voluntarily participated. Each latent construct of the study was validated using confirmatory factor analysis (CFA). Structural equation modeling (SEM) was used to examine the relationships between the variables of the study. The IBM SPSS Amos 25 software was used to analyze the CFA and SEM.
Show less - Date Issued
- 2019
- Identifier
- CFE0007806, ucf:52348
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007806
- Title
- Characterization of Anisotropic Mechanical Performance of As-Built Additively Manufactured Metals.
- Creator
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Siddiqui, Sanna, Gordon, Ali, Raghavan, Seetha, Bai, Yuanli, Sohn, Yongho, University of Central Florida
- Abstract / Description
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Additive manufacturing (AM) technologies use a 3D Computer Aided Design (CAD) model to develop a component through a deposition and fusion layer process, allowing for rapid design and geometric flexibility of metal components, for use in the aerospace, energy and biomedical industries. Challenges exist with additive manufacturing that limits its replacement of conventional manufacturing techniques, most especially a comprehensive understanding of the anisotropic behavior of these materials...
Show moreAdditive manufacturing (AM) technologies use a 3D Computer Aided Design (CAD) model to develop a component through a deposition and fusion layer process, allowing for rapid design and geometric flexibility of metal components, for use in the aerospace, energy and biomedical industries. Challenges exist with additive manufacturing that limits its replacement of conventional manufacturing techniques, most especially a comprehensive understanding of the anisotropic behavior of these materials and how it is reflected in observed tensile, torsional and fatigue mechanical responses. As such, there is a need to understand how the build orientation of as-built additively manufactured metals, affects mechanical performance (e.g. monotonic and cyclic behavior, cyclically hardening/softening behavior, plasticity effects on fatigue life etc.); and to use constitutive modeling to both support experimental findings, and provide approximations of expected behavior (e.g. failure surfaces, monotonic and cyclic response, correlations between tensile and fatigue properties), for orientations and experiments not tested, due to the expensive cost associated with AM. A comprehensive framework has been developed to characterize the anisotropic behavior of as-built additively manufactured metals (i.e. Stainless Steel GP1 (SS GP1), similar in chemical composition to Stainless Steel 17-4PH), through a series of mechanical testing, microscopic evaluation and constitutive modeling, which were used to identify a reduced specimen size for characterizing these materials. An analysis of the torsional response of additively manufactured Inconel 718 has been performed to assess the impact of build orientation and as-built conditions on the shearing behavior of this material. Experimental results from DMLS SS GP1 and AM Inconel 718 from literature were used to constitutively model the material responses of these additively manufactured metals. Overall, this framework has been designed to serve as standard, from which build orientation selection can be used to meet specific desired industry requirements.
Show less - Date Issued
- 2018
- Identifier
- CFE0007097, ucf:52883
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007097
- Title
- EFFECTIVE SCHOOL CHARACTERISTICS AND STUDENT ACHIEVEMENT CORRELATES AS PERCEIVED BY TEACHERS IN AMERICAN STYLE INTERNATIONAL SCHOOLS.
- Creator
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Doran, James, Allen, Kay, University of Central Florida
- Abstract / Description
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The purpose of this study is to investigate the relationships between effective school characteristics and norm referenced standardized test scores in American-style international schools. In contrast to schools in traditional effective schools research, international schools typically have middle to high SES families, and display average to above average achievement. Eleven effective school characteristics were identified and correlated with standardized test scores for grades 4, 6, and 8...
Show moreThe purpose of this study is to investigate the relationships between effective school characteristics and norm referenced standardized test scores in American-style international schools. In contrast to schools in traditional effective schools research, international schools typically have middle to high SES families, and display average to above average achievement. Eleven effective school characteristics were identified and correlated with standardized test scores for grades 4, 6, and 8 and high school SAT scores. Data was gathered from an online teacher questionnaire designed for this study. All eleven characteristics were present in high performing international schools while frequent analysis of student progress, high academic expectations and positive school environment were more prominent. Positive school environment, high academic expectations, strong instructional leadership and cultural diversity were chosen as important characteristics of an effective international school. Learning time is maximized was the only characteristic that was significantly correlated with achievement and only in grades 4, 6 and 8. There was no statistically significant relationship found between norm referenced test scores and the aggregate effective school characteristics score.
Show less - Date Issued
- 2004
- Identifier
- CFE0000245, ucf:46244
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000245
