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- Title
- Fatigue : investigation of a human factor for aviation curricula.
- Creator
-
Weitzel, Thomas R., Orwig, Gary W., Education
- Abstract / Description
-
University of Central Florida College of Education Thesis; This descriptive study investigated the perceived problem of human fatigue as an operational consideration within the U.S. air carrier industry and the status of fatigue as content within U.S. aviation education/training curricula. An instrument was developed and expert-validated for self-completion by the following three groups (each with its sample size): (a) aviation higher education, represented by a mailing to 50 individuals; (b)...
Show moreUniversity of Central Florida College of Education Thesis; This descriptive study investigated the perceived problem of human fatigue as an operational consideration within the U.S. air carrier industry and the status of fatigue as content within U.S. aviation education/training curricula. An instrument was developed and expert-validated for self-completion by the following three groups (each with its sample size): (a) aviation higher education, represented by a mailing to 50 individuals; (b) air carrier training/management, represented by a mailing to 50 individuals; and (c) a professional training group of 58 general aviation flight instructors, with administration by the researcher during scheduled company meetings. The resultant SPSS data set consisted of 116 cases. Eight demographic variables were reported and analyzed with the analysis of variance; and the definition of fatigue, a multiple choice item, was tested for the chi-square goodness-of-fit distribution. The remaining 21 variables were subjected to a factor analysis, utilizing principal-axis fatoring for extraction; orthogonal rotation, which forced the derived factors to be uncorrelated; and varimax, a variance maximizing procedure. The resultant 8 factors removed the duplication from the 21 correlated variables and, when scored, became variables within the SPSS data set. The normalized factor scores were subjected to analysis of variance and post hoc comparison for any significance of difference between the three groups; minor group differences were found for three of the eight factors. The data supported the literature review with respect to human fatigue being perceived as an operational consideration on the flightdecks of U.S. air carriers. The data and the literature also indicated that fatigue is present as content within U.S. aviation curricula. However, the answers to both research questions involved a matter of degree. Additionally, the data indicated that not all students within U.S. aviation have exposure to fatigue content within their curricula. Teaching the concepts and management of fatigue to some of these student may be as important as (more important than) fatigue as curricular content for flight crews. Future research in the development of a curriculum paradigm for human fatigue in U.S. aviation might utilize the eight factors derived as constructs by the factor analysis utilized in this study.
Show less - Date Issued
- 1997
- Identifier
- CFR0010873, ucf:53051
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0010873
- Title
- The effect of varying temperature, flux and pretreatment on the microfiltration of Lake Michigan water.
- Creator
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Kopp, Karen Linda, Taylor, James S., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; This study investigated microfiltration of Lake Michigan Water for the production of drinking water. A 60 gpm Memcor microfiltration pilot plant was operated for nine months at Manitowoc, Wisconsin to determine and model the performance characteristics of a microfiltration pilot plant for varying surface water conditions. Statistical regression and modeling was used to determine and develop quantitative relationships between time of...
Show moreUniversity of Central Florida College of Engineering Thesis; This study investigated microfiltration of Lake Michigan Water for the production of drinking water. A 60 gpm Memcor microfiltration pilot plant was operated for nine months at Manitowoc, Wisconsin to determine and model the performance characteristics of a microfiltration pilot plant for varying surface water conditions. Statistical regression and modeling was used to determine and develop quantitative relationships between time of operation and several operational variables for water quality and productivity. Modifications of Darcy's Law and flux decline data were used to develop a model relating temperature and flux to cleaning frequency. Statistical hypothesis testing and associated modeling were used to determine if relationships existed between the water quality and the independent operating variables affecting microfiltration. The study demonstrated that the filtered water turbidity or particle count did not carry with the flux or the influent water temperature and that the degree of turbidity or particle count removal was dependent on the raw water turbidity or particle count. Direct filtration of an alum pretreated feed water was found to greatly increase time of operation between cleanings for temperatures below 48°F. As expected the size exclusion membrane process was found to have no effect on dissolved of diffusion controlled solute rejection. the investigation found the turbidity and particle counts of the microfiltered water was less than the same for the finished water produced by the conventional alum coagulation, sedimentation and filtration process. The investigation demonstrated that microfiltration could be used to consistently produce a drinking water that met or exceeded state or federal requirements at Manitowoc. Based on the results of this investigation, a recommendation was made to use microfiltration as the treatment process of choice for the treatment of Lake Michigan Water.
Show less - Date Issued
- 1997
- Identifier
- CFR0010872, ucf:53052
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0010872
- Title
- The effects of glucose and fatty acids on enhanced biological phosphorus removal using a sequencing batch reactor.
- Creator
-
Khouri, Tarek Zaki, Randall, Andrew A., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; Two anaerobic/aerobic sequencing batch reactors (SBRs) were used to evaluate enhanced biological phosphorus removal (EBPR). The first SBR, designated the Glucose SBR, was run for a period of four months. It received a synthetic wastewater plus glucose as a supplemental carbon source. The second SBR, the Isovaleric SBR, was run for three months. During the first month, isovaleric acid was its supplemental carbon source while for the...
Show moreUniversity of Central Florida College of Engineering Thesis; Two anaerobic/aerobic sequencing batch reactors (SBRs) were used to evaluate enhanced biological phosphorus removal (EBPR). The first SBR, designated the Glucose SBR, was run for a period of four months. It received a synthetic wastewater plus glucose as a supplemental carbon source. The second SBR, the Isovaleric SBR, was run for three months. During the first month, isovaleric acid was its supplemental carbon source while for the remaining time period, no supplemental carbon source was added to the feed. Steady-state data from the SBR receiving isovalerate yielded the highest phosphorus (P) removals observed during the study, with a mixed liquor volatile suspended solid (MLVSS) P content of 7.2%. The next highest removals were observed when prefermented glucose was received, which yielded a MLVSS P content of 6.4%. The lowest removals were observed when no supplemental carbon source was added to the SBR influent, with at 4.4% MLVSS P content. Batch experiments were also conducted to quantify the effect of EBPR of glucose and the volatile fatty acids (VFAs) acetic acid, propionic acid, valeric acid, and isovaleric acid. Compounds giving the largest anaerobic P release ultimately yielded the lowest effluent P concentrations. At 0.80 mmoles/l, isovaleric acid resulted in anaerobic P released 9.5 mg/l greater than an equal amount of glucose or propionic acid, but ultimately gave effluent P values roughly 4 mg/l lower than either. Ratios of aerobic P uptake/anaerobic P release were found to be roughly equal for all the VFAs when the VFAs were compared on a molar basis. Propionic acid had aerobic P uptake/anaerobic P release ratios similar to the other VFAs. It also behaved the same as all the other VFAs with respect to the effect of concentrations added to the batch experiment; however, the magnitude of its removal was significantly lower than all the other substrates. Glucose, on the other hand, behaved differently from all the VFAs. Glucose aerobic P uptake/anaerobic P release ratios varied with concentration, which was not the case for the others substrates. Also, glucose P net removals decreased at concentrations higher than 0.60 mmoles/l. Glucose also resulted in net P removals roughly 2mg/l higher than propionic acid, but ultimately gave lower net P removal than isovaleric, valeric and acetic acids.
Show less - Date Issued
- 1996
- Identifier
- CFR0010871, ucf:53053
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0010871
- Title
- Computing optimal cocomo effort multiplier values and optimal casebase subsets using monte carlo methods.
- Creator
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Maidhof, Robert Joseph, Linton, Darrell G., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; There have been many studies performed and techniques applied to solve the problem of estimating man-month effort for software projects. Despite all the effort expended to solving this problem the results achieved from the various techniques have not been embraced by the software community as very reliable or accurate. This thesis uses Monte Carlo methods to obtain optimal values for COCOMO effort multipliers which minimize the...
Show moreUniversity of Central Florida College of Engineering Thesis; There have been many studies performed and techniques applied to solve the problem of estimating man-month effort for software projects. Despite all the effort expended to solving this problem the results achieved from the various techniques have not been embraced by the software community as very reliable or accurate. This thesis uses Monte Carlo methods to obtain optimal values for COCOMO effort multipliers which minimize the average of the absolute values of the relative errors (AARE) of man-month estimate for two industry supplied casebases. For example, when using three COCOMO cost drivers (complexity, language experience, application experience) and the COCOMO effort multiplier values, AARE values were 60% for casebase 1 and 53% for casebase 2; using Monte Carlo to obtain optimal effort multiplier values, AARE values were 34% for casebase 1 and 41% for casebase 2. By repeatedly removing the cases which contributed the greatest Absolute Relative Error, the Monte Carlo method was also used to determine optimal casebase subsets with AARE values of less than 10%. This latter approach identifies casebase cases for which the cost drivers may have been rated incorrectly or cases which are not rated consistently with respect to a subset of cases.
Show less - Date Issued
- 1996
- Identifier
- CFR0011954, ucf:53104
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011954
- Title
- Nonlinear robust control of a series dc motor utilizing the recursive design approach.
- Creator
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Burridge, Michael J., Qu, Zhihua, Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; In this thesis, the investigation of asymptotic stability of the series DC motor with unknown load-torque and unknown armature inductance is considered. The control technique of recursive, or backstepping, design is employed. Three cases are considered. In the first case, the system is assumed to be perfectly known. In the second case, the load torque is assumed to be unknown and a proportional-integral controller is developed to...
Show moreUniversity of Central Florida College of Engineering Thesis; In this thesis, the investigation of asymptotic stability of the series DC motor with unknown load-torque and unknown armature inductance is considered. The control technique of recursive, or backstepping, design is employed. Three cases are considered. In the first case, the system is assumed to be perfectly known. In the second case, the load torque is assumed to be unknown and a proportional-integral controller is developed to compensate for this unknown quantity. In the final case, it is assumed that two system parameters, load torque and armature inductance, are not known exactly, but vary from expected nominal values within a specified range. A robust control is designed to handle this case. The Lyapunov stability criterion is applied in all three cases to prove the stability of the system under the developed control. The results are then verified through the use of computer simulation.
Show less - Date Issued
- 1995
- Identifier
- CFR0011942, ucf:53109
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011942
- Title
- Telecourse and traditional computer applications: exploring the impact of review sessions.
- Creator
-
Bourke, Carol Odette, Kysilka, Marcella L., Education
- Abstract / Description
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University of Central Florida College of Education Thesis; The purpose of the study was to explore the effects of review sessions on student achievement and retention in a computer applications course taught by televised distance learning and traditional instruction. Identified within the study were method of instruction, review, and grades in televised and traditional computer applications courses. A quasi-experimental design was used to measure the effects of review sessions on student...
Show moreUniversity of Central Florida College of Education Thesis; The purpose of the study was to explore the effects of review sessions on student achievement and retention in a computer applications course taught by televised distance learning and traditional instruction. Identified within the study were method of instruction, review, and grades in televised and traditional computer applications courses. A quasi-experimental design was used to measure the effects of review sessions on student achievement and retention in computer applications classes. Intact classes were used to form the 4 groups used in this study. Randomization was limited to choices students made in registering for the classes. The control groups for this study consisted of those students enrolled in traditional and telecourse computer applications during the Fall 1995 and Spring 1996 semesters for a total of 137 students. These students received no review sessions as part of their instruction. The experimental groups were formed by those students enrolled in the traditional and telecourse computer applications during the Fall 1996 semester for a total of 102 students. These students received review sessions as part of their instruction. Findings indicated that method of instruction does not provide significant differences in terms of grades and retention between the telecourse and traditional classes. Results indicated that there were significant differences in terms of review on grades with telecourse and traditional classes. Student responses indicated that review sessions were helpful. Recommendations were made for improved efforts to enhance strategies in traditional and distance learning and for continued research in traditional and distance learning.
Show less - Date Issued
- 1997
- Identifier
- CFR0010875, ucf:53048
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0010875
- Title
- Color image enhancement using both chromatic and luminance components.
- Creator
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Hague, George Eric, Weeks, Arthur R., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; A vast amount of work has been published regarding grayscale processing of digital images. Although some of this work has been adapted for color images, many of the resulting algorithms neglect the correlation that exists between the individual RGB color components. Consequently, they introduce color artifacts. Attempts have been made to decouple the RGB components through color space transformations that isolate the luminance from...
Show moreUniversity of Central Florida College of Engineering Thesis; A vast amount of work has been published regarding grayscale processing of digital images. Although some of this work has been adapted for color images, many of the resulting algorithms neglect the correlation that exists between the individual RGB color components. Consequently, they introduce color artifacts. Attempts have been made to decouple the RGB components through color space transformations that isolate the luminance from the chromatic information. Color image enhancement is then considered a two step process, where the luminance and the chromatic components are processed independently. However, the RGB color space only has a finite number of available colors, which limits the attainable chromatic values for any given luminance level. This recoupling of the chromatic and luminance components constrains the independent processing of these two components. This thesis investigates this coupling and how it effects a number of color image processing algorithms. Specifically, new algorithms for color histogram equalization, automatic white balance and color filtering are presented using the C-Y (color difference) color model. Coupling the chromatic components to the luminance produces improved white balanced results and enhances the ability of histogram equalization to increase saturation contrast. Furthermore, several adaptive filters are implemented using the C-Y color space. Because this color model closely matches the human concept of color, the noise is filtered from color components that closely match the perceptually significant quantities. This improves the results for these adaptive filters, but also requires special attention when filtering the hue component. Improper filtering of the hue component can often lead to color artifacts.
Show less - Date Issued
- 1994
- Identifier
- CFR0011934, ucf:53115
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011934
- Title
- Consumption and loss of formaldehyde in electroless copper plating.
- Creator
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Sutch, Peter John F., Dietz, John D., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; The objectives of this research were to quantify formaldehyde consumption due to plating and parasitic reactions and determine the magnitude and distribution of formaldehyde losses from the electroless copper plating process. Plating and rinse bath samples obtained from three electroless copper plating operations were analyzed for formaldehyde and copper in order to develop a mass balance analysis about the plating bath for periods...
Show moreUniversity of Central Florida College of Engineering Thesis; The objectives of this research were to quantify formaldehyde consumption due to plating and parasitic reactions and determine the magnitude and distribution of formaldehyde losses from the electroless copper plating process. Plating and rinse bath samples obtained from three electroless copper plating operations were analyzed for formaldehyde and copper in order to develop a mass balance analysis about the plating bath for periods of active production and no production. Fugitive air and stack releases of formaldehyde were estimated using emission factors developed from air sampling at the three facilities. It was determined that approximately 90% of the formaldehyde added to the plating process was consumed by some type of chemical reaction. The remaining 10% of formaldehyde represents losses from the plating operation. For the facilities with a waste plating solution stream, atmospheric losses accounted for approximately 25% of the total losses. The mass of fugitive air formaldehyde measured approximately 2.8 times that escaping through the stack. Dragout accounted for approximately 2.3% of the losses with the remaining going to the waste stream. For the facility without a plating solution waste stream, formaldehyde losses were distributed 59% to atmospheric releases and 41% to the rinse tank. Fugitive and stack releases were approximately the same at 29% of the formaldehyde losses. Formaldehyde consumption due to parasitic reactions for periods of active plating and no plating were determined for two facilities. The rate of parasitic consumption during periods of production was found to be approximately 3 times greater than that for no production. The rate of parasitic consumption was observed to increase with increasing bath temperature.
Show less - Date Issued
- 1993
- Identifier
- CFR0011932, ucf:53116
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011932
- Title
- Development of scale factors for clarifier design based on batch settling data.
- Creator
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Anderson, Robert K, Dietz, John D., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; Traditionally, batch settling tests have been employed to determine the values of the settling parameters V0 and K of the Vesilind equation which represents activated sludge settling velocity as a function of solids concentration. It remains unresolved how closely batch settling tests describe settling in full-scale clarifiers. An experimental procedure was developed to determine scale factors between batch settling and full-scale...
Show moreUniversity of Central Florida College of Engineering Thesis; Traditionally, batch settling tests have been employed to determine the values of the settling parameters V0 and K of the Vesilind equation which represents activated sludge settling velocity as a function of solids concentration. It remains unresolved how closely batch settling tests describe settling in full-scale clarifiers. An experimental procedure was developed to determine scale factors between batch settling and full-scale solids flux curves. An experimental protocol was determined for full-scale clarifier operation, including specific criteria of necessary instrumentation and operational flexibility. Several graphical techniques were evaluated and a procedure was selected to determine a scale factor between batch and full-scale settling. The specified procedure requires determination of underflow velocity and concentration. The scale factor was approximately 0.84 as applied to the limiting flux, thus clarifiers designed from batch settling tests would be underdesigned. In addition, a methodology was developed to account for batch flux curve variability in the form of a safety factor. Finally, a design procedure was recommended to calculate clarifier area based on the scale factor determined from the batch and full-scale experiments.
Show less - Date Issued
- 1989
- Identifier
- CFR0011927, ucf:53122
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011927
- Title
- An historical analysis of the philosophies of the vocational education leaders in relation to the 1990 Carl D. Perkins vocational and applied technology education act amendments.
- Creator
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Woodley, Cynthia D., Hudson, Larry, Education
- Abstract / Description
-
University of Central Florida College of Education Thesis; Federal vocational education legislation has undergone drastic changes in recent years. This study was designed to determine the educational philosophies of the leaders who pushed for the 1990 Carl D. Perkins Vocational and Applied Technology Education Act Amendments and the degree to which the amendments reflected the philosophies of those leaders. Data were collected on testimonies given before the United State[s] Congress during...
Show moreUniversity of Central Florida College of Education Thesis; Federal vocational education legislation has undergone drastic changes in recent years. This study was designed to determine the educational philosophies of the leaders who pushed for the 1990 Carl D. Perkins Vocational and Applied Technology Education Act Amendments and the degree to which the amendments reflected the philosophies of those leaders. Data were collected on testimonies given before the United State[s] Congress during hearings related to the act, to identify who the leaders were. Once the leaders were identified, the published literature and testimony of each leaders was analyzed using a model developed by Lloyd Duck and the educational philosophy for each leader was identified. Finally, provisions of the act were compared to the philosophies and testimonies of the leaders to identify if the act paralleled the philosophical rationale of the leaders. This researcher found that of the leaders who pushed for the act, the majority, though not all, were of an experimentalist educational philosophy. Further analysis revealed that while the act appeared on the surface to match well with several different educational philosophies, it actually did not match the philosophies of all of the leaders. Because of this, this researcher concluded that implementation of the act may not be successful unless a new educational philosophy is established.
Show less - Date Issued
- 1992
- Identifier
- CFR0011930, ucf:53121
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011930
- Title
- Gaussian beam resonator formalism using the yy method.
- Creator
-
Menard, Kenneth A., Harvey, James E, Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; A simple and powerful new paraxial ray formalism is shown to provide an alternate method for designing Gaussian Beam Resonators. The theory utilizes the Delano yybar diagram approach and is an extension of the recent work by Shack and Kessler for laser systems. The method is shown to be complementary to the conventional ABCD method and is founded upon J.A. Arnaud's pioneering ideas for complex rays. The thesis develops an analytic...
Show moreUniversity of Central Florida College of Engineering Thesis; A simple and powerful new paraxial ray formalism is shown to provide an alternate method for designing Gaussian Beam Resonators. The theory utilizes the Delano yybar diagram approach and is an extension of the recent work by Shack and Kessler for laser systems. The method is shown to be complementary to the conventional ABCD method and is founded upon J.A. Arnaud's pioneering ideas for complex rays. The thesis develops an analytic formulation of a ray based complex wavefront curvature and yields a clearly generalized description of spherical wave propagation, for which Gaussian beams are considered a special case. The resultant theory unifies the complex q parameter and the ABCD law, with the yybar complex ray components and also suggests that the ABCD law for the complex q parameter has its origin in the yybar complex ray. New fundamental equations for designing stable multi-element resonators using the yybar coordinates are derived, and it is shown that the yybar diagram provides a novel method for defining automatically stable resonators. Various applications for the yybar design technique are also discussed, including the setting of convenient design constraints, the description of M2 beams, generating phase diagrams, and resonator synthesis and analysis.
Show less - Date Issued
- 1995
- Identifier
- CFR0011940, ucf:53106
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011940
- Title
- Florida social studies leaders' perceptions regarding an afrocentric curriculum.
- Creator
-
Banks, Vicki Kaplan, Cornett, Jeff, Education
- Abstract / Description
-
University of Central Florida College of Education Thesis; The purpose of this research study was to gain insight into the perceptions Florida's leaders have regarding the inclusion of an Afrocentric curriculum. The leaders chosen for this study were the Florida Council for the Social Studies Board and the Association of Social Studies Supervisors. These leaders were sent a questionnaire that contained 57 statements about social studies curriculum content in a Likert scale format. The results...
Show moreUniversity of Central Florida College of Education Thesis; The purpose of this research study was to gain insight into the perceptions Florida's leaders have regarding the inclusion of an Afrocentric curriculum. The leaders chosen for this study were the Florida Council for the Social Studies Board and the Association of Social Studies Supervisors. These leaders were sent a questionnaire that contained 57 statements about social studies curriculum content in a Likert scale format. The results of the survey were reported by using mean scores and frequency distributions. The Likert survey statements examined respondents' viewpoints with regard to diversity, Afrocentrism, and Eurocentrism. The results of the survey were used to infer the respondents' perceptions regarding the five research questions. 1. What was the perceived importance of considering the diverse nature of an ethnicity in respect to the development of curriculum and instruction? 2. What was the perceived level of interest regarding the incorporation of an Afrocentric perspective into the Social Studies Curriculum? 3. How did the respondents perceive the incorporation of an alternate curriculum maintaining diverse perspectives? 4. Did the respondents believe the social studies curriculum should be altered to cater to the learning styles of ethnic and cultural groups? 5. Was there a perceived need for diverse assessment techniques to gauge the academic success of students from various cultural and ethnic groups? The mean scores assigned to each research question indicated that the leaders in the social studies agreed that diverse cultures should be included within the mainstream curriculum and that alternative assessment techniques should be used to measure those ideas. However, there was little interest in permitting the ethnicity of the school's population guide curriculum and instruction decision. Furthermore, the leaders seemed more interested in a multicultural curriculum than a curriculum incorporating only an Afrocentric perspective.
Show less - Date Issued
- 1998
- Identifier
- CFR0011944, ucf:53111
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011944
- Title
- Electromagnetic focusing properties of chirped metallic gratings.
- Creator
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Schmidt, Jeffrey C., Christodoulou, Christos G., Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; The focusing properties of chirped diffraction gratings have long been studied and often used in applications at optical frequencies. Chirped metallic gratings of this type have also been studied theoretically at microwave frequencies, but no attempt has been made to experimentally examine or utilize the focusing properties of these structures at microwave frequencies. This thesis presents an experimental analysis of the focusing...
Show moreUniversity of Central Florida College of Engineering Thesis; The focusing properties of chirped diffraction gratings have long been studied and often used in applications at optical frequencies. Chirped metallic gratings of this type have also been studied theoretically at microwave frequencies, but no attempt has been made to experimentally examine or utilize the focusing properties of these structures at microwave frequencies. This thesis presents an experimental analysis of the focusing properties of chirped metallic gratings. These gratings are designed to focus electromagnetic energy at a predetermined position by varying strip width and spacing as a function of position. The diffraction gratings are characterized, and experimentally measured results are compared to theoretical data.
Show less - Date Issued
- 1992
- Identifier
- CFR0011931, ucf:53123
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011931
- Title
- Integration of artificial neural networks and simulation modeling in a decision support system.
- Creator
-
LeCroy, Kenney, Mollaghasemi, Mansooreh, Engineering
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; A simulation based decision support system is developed for AT[and]T Microelectronics in Orlando. This system uses simulation modeling to capture the complex nature of semiconductor test operations. Simulation, however, is not a tool for optimizations by itself. Numerous executions of the simulation model must generally be performed to narrow in on a set of proper decision parameters. As a means of alleviating this shortcoming,...
Show moreUniversity of Central Florida College of Engineering Thesis; A simulation based decision support system is developed for AT[and]T Microelectronics in Orlando. This system uses simulation modeling to capture the complex nature of semiconductor test operations. Simulation, however, is not a tool for optimizations by itself. Numerous executions of the simulation model must generally be performed to narrow in on a set of proper decision parameters. As a means of alleviating this shortcoming, artificial neural networks are used in conjunction with simulation modeling to aid management in the decision making process. The integration of simulation and neural networks in a comprehensive decision support system, in effect, learns the reverse of the simulation process. That is, given a set of goals defined for performance measures, the decision support system suggests proper values for decision parameters to achieve those goals.
Show less - Date Issued
- 1994
- Identifier
- CFR0011935, ucf:53114
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011935
- Title
- An analysis of the early retirement programs offered during the 1992-1993 school year by the public school districts in the state of Florida.
- Creator
-
Berry, Peter B., Murray, Kenneth T., Education
- Abstract / Description
-
University of Central Florida College of Education Thesis; This study surveyed the public school districts in Florida and examined the 19 school districts which utilized incentive to motivate school district employees to retire. The data was collected for the 1992-1993 school year. A survey administered to all of the 67 school districts in Florida determined what types of incentives were being used, to what degree the school districts were able to reduce costs, and what types of incentives...
Show moreUniversity of Central Florida College of Education Thesis; This study surveyed the public school districts in Florida and examined the 19 school districts which utilized incentive to motivate school district employees to retire. The data was collected for the 1992-1993 school year. A survey administered to all of the 67 school districts in Florida determined what types of incentives were being used, to what degree the school districts were able to reduce costs, and what types of incentives were effective. In depth information was obtained from interviews with assistant superintendents, personnel directors, and State Department of Education Specialists. A relationship was found between the amount of discretionary income and the type of incentive offered by the school districts. The school districts with budgets under $60 million were only able to primarily offer bonus incentives, while those above this level used annuities or combinations. An experiment was discovered using a different type of incentive--insurance. A negative relationship was discovered between annuities and employee interest during the year of the study. Recommendations were made for additional research on the insurance program as well as other cost cutting improvements.
Show less - Date Issued
- 1994
- Identifier
- CFR0011937, ucf:53108
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0011937
- Title
- Efficient techniques for management and delivery of video data.
- Creator
-
Oh, Junghwan, Hua, Kien A., Engineering and Computer Science
- Abstract / Description
-
University of Central Florida College of Engineering Thesis; The rapid advances in electronic imaging, storage, data compression telecommunications, and networking technology have resulted in a vast creation and use of digital videos in many important applications such as digital libraries, distance learning, public information systems, electronic commerce, movie on demand, etc. This brings about the need for management as well as delivery of video data. Organizing and managing video data,...
Show moreUniversity of Central Florida College of Engineering Thesis; The rapid advances in electronic imaging, storage, data compression telecommunications, and networking technology have resulted in a vast creation and use of digital videos in many important applications such as digital libraries, distance learning, public information systems, electronic commerce, movie on demand, etc. This brings about the need for management as well as delivery of video data. Organizing and managing video data, however, is much more complex than managing conventional text data due to their semantically rich and unstructured contents. Also, the enormous size of video files requires high communication bandwidth for data delivery. In this dissertation, I present the following techniques for video data management and delivery. Decomposing video into meaningful pieces (i.e., shots) is a very fundamental step to handling the complicated contents of video data. Content-based video parsing techniques are presented and analyzed. In order to reduce the computation cost substantially, a non-sequential approach to shot boundary detection is investigated. Efficient browsing and indexing of video data are essential for video data management. Non-linear browsing and cost-effective indexing schemes for video data based on their contents are described and evaluated. In order to satisfy various user requests, delivering long videos through the limited capacity of bandwidth is challenging work. To reduce the demand on this bandwidth, a hybrid of two effective approaches, periodic broadcast and scheduled multicast, is discussed and simulated. The current techniques related to the above works are discussed thoroughly to explain their advantages and disadvantages, and to make the new improved schemes. The substantial amount of experiments and simulations as well as the concepts are provided to compare the introduced techniques with the other existing ones. The results indicate that they outperform recent techniques by a significant margin. I conclude the dissertation with a discussing of future research directions.
Show less - Date Issued
- 2000
- Identifier
- CFR0001719, ucf:52918
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0001719
- Title
- Global domination of factors of a graph.
- Creator
-
Carrington, Julie R., Brigham, Robert C., Arts and Sciences
- Abstract / Description
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University of Central Florida College of Arts and Sciences Thesis; A factoring of a graph G = (V,E) is a collection of spanning subgraphs F1, F2,..., Fk, known as factors into which the edge set E has been partitioned. A dominating set of a graph is a set of nodes such that every node in the graph is either contained in the set or has an edge to some node in the set. Each factor Fi is itself a graph and so has a dominating set. This set is called a local dominating set or LDS. An LDS of...
Show moreUniversity of Central Florida College of Arts and Sciences Thesis; A factoring of a graph G = (V,E) is a collection of spanning subgraphs F1, F2,..., Fk, known as factors into which the edge set E has been partitioned. A dominating set of a graph is a set of nodes such that every node in the graph is either contained in the set or has an edge to some node in the set. Each factor Fi is itself a graph and so has a dominating set. This set is called a local dominating set or LDS. An LDS of minimumsize contains (gamma)i nodes. In addition, there is some set of nodes named a global dominating set which dominates all of the factors. If a global dominating set is of a minimum size, it is called a GDS and contains (gamma) nodes. A central question answered by this dissertation is under what circummstances, given a set of integers (gamma)1, (gamma)2, ..., (gamma)k, and (gamma) there is a graph which can be factored into k factors in such a way that a minimum LDS of Fi has size (gamma)i, 1 [less than or equal to] i [less than or equal to] k, and GDS has size (gamma).
Show less - Date Issued
- 1992
- Identifier
- CFR0001860, ucf:52916
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0001860
- Title
- Edge Contours.
- Creator
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Williams, Donna J., Shah, Mubarak A., Arts and Sciences
- Abstract / Description
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University of Central Florida College of Arts and Sciences Thesis; The accuracy with which a computer vision system is able to identify objects in an image is heavily dependent upon the accuracy of the low level processes that identify which points lie on the edges of an object. In order to remove noise and fine texture from an image, it is usually smoothed before edge detection is performed. This smoothing causes edges to be displaced from their actual location in the image. Knowledge about...
Show moreUniversity of Central Florida College of Arts and Sciences Thesis; The accuracy with which a computer vision system is able to identify objects in an image is heavily dependent upon the accuracy of the low level processes that identify which points lie on the edges of an object. In order to remove noise and fine texture from an image, it is usually smoothed before edge detection is performed. This smoothing causes edges to be displaced from their actual location in the image. Knowledge about the changes that occur with different degrees of smoothing (scales) and the physical conditions that cause these changes is essential to proper interpretation of the results obtained. In this work the amount of delocalization and the magnitude of the response to the Normalized Gradient of Gaussian operator are analyzed as a function of cr, the standard deviation of the Gaussian. As a result of this analysis it was determined that edge points could be characterized as to slope, contrast, and proximity to other edges. The analysis is also used to define the size that the neighborhood of an edge point must be in order to assure its containing the delocalized edge point at another scale when o is known. Given this theoretical background, an algorithm was developed to obtain sequential lists of edge points. This used multiple scales in order to achieve the superior localization and detection of weak edges possible with smaller scales combined with the noise suppression of the larger scales. The edge contours obtained with this method are significantly better than those achieved with a single scale. A second algorithm was developed to allow sets of edge contour points to be represented as active contours so that interaction with a higher level process is possible. This higher level process could do such things as determine where corners or discontinuities could appear. The algorithm developed here allows hard constraints and represents a significant improvement in speed over previous algorithms allowing hard constraints, being linear rather than cubic.
Show less - Date Issued
- 1989
- Identifier
- CFR0000160, ucf:52912
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0000160
- Title
- Finding paths in the rotation graph of binary trees.
- Creator
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Rogers, Rodney O., Dutton, Ronald D., Arts and Sciences
- Abstract / Description
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University of Central Florida College of Arts and Sciences Thesis; A binary tree coding scheme is a bijection mapping a set of binary trees to a set of integer tuples called codewords. One problem considered in the literature is that of listing the codewords for n-node binary trees, such that successive codewords represent trees differing by a single rotation, a standard operation for rebalancing binary search trees. Then, the codeword sequence corresponds to an Hamiltonian path in the...
Show moreUniversity of Central Florida College of Arts and Sciences Thesis; A binary tree coding scheme is a bijection mapping a set of binary trees to a set of integer tuples called codewords. One problem considered in the literature is that of listing the codewords for n-node binary trees, such that successive codewords represent trees differing by a single rotation, a standard operation for rebalancing binary search trees. Then, the codeword sequence corresponds to an Hamiltonian path in the rotation graph Rn of binary trees, where each node is labelled with an n-node binary tree, and an edge connects two nodes when their trees differ by a single rotation. A related problem is finding a shortest path between two nodes in Rn, which reduces to the problem of transforming one binary tree into another using a minimum number of rotations. Yet a third problem is determining properties of the rotation graph. Our work addresses these three problems.
Show less - Date Issued
- 1996
- Identifier
- CFR0000193, ucf:52941
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0000193
- Title
- Writing as a public relations task: how much do public relations practitioners write?.
- Creator
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Stansberry, Frank R., Taylor, K. Phillip, Arts and Sciences
- Abstract / Description
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University of Central Florida College of Arts and Sciences Thesis; The purpose of this study was to investigate how much public relations people write in the course of their work; to determine if the amount and type of writing varies with experience, job type or employer; and to investigate what other tasks besides writing public relations professionals do. The sample was 198 members of the Public Relations Society of America who responded to a nation-wide mailing of 500 people selected from...
Show moreUniversity of Central Florida College of Arts and Sciences Thesis; The purpose of this study was to investigate how much public relations people write in the course of their work; to determine if the amount and type of writing varies with experience, job type or employer; and to investigate what other tasks besides writing public relations professionals do. The sample was 198 members of the Public Relations Society of America who responded to a nation-wide mailing of 500 people selected from the Society's membership directory. Results showed that public relations practitioners spent 36.5 percent of their time writing. Overall, public relations people spend more time on publicity, media relations, and business administration than on any other function, but counseling management and research--two emerging area--are rating in the top 50 percent. Thus, while this study does not provide any startling new information on the public relations industry, it does provide, for the first time, empirical evidence of what an average or typical public relations practitioner does. That was the primary goal of the study.
Show less - Date Issued
- 1989
- Identifier
- CFR0008148, ucf:52953
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFR0008148