View All Items

Title: An efficient method for representing and computing transitive closure over temporal relations.
Creator: Kovarik, Vincent J., Gonzalez, Avelino, Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; The need for temporal reasoning is found throughout the engineering disciplines. James Allen introduced a representation for temporal reasoning based upon the concept of intervals. This approach provides a rich set of temporal relations for reasoning over events and changes in state. The full temporal algebra is NP-complete however. The algorithm developed by Allen executes in 0(n3) time but only ensures consistency between any...
Show moreUniversity of Central Florida College of Engineering Thesis; The need for temporal reasoning is found throughout the engineering disciplines. James Allen introduced a representation for temporal reasoning based upon the concept of intervals. This approach provides a rich set of temporal relations for reasoning over events and changes in state. The full temporal algebra is NP-complete however. The algorithm developed by Allen executes in 0(n3) time but only ensures consistency between any three intervals. This research presents an approach to representing interval relations as a bit-encoded form which captures the relationships between the end-points of the intervals. A bit-algebra is then defined which provides an algorithmic method for computing transitive relations without requiring the table lookup of Allen's algorithm. By reducing the set of ambiguous interval representations to the set of relationships which have unknown temporal extent, a robust subset of the full algebra is defined which maintains the direct computation of transitive relationships.
Show less
Date Issued: 1994
Identifier: CFR0001859, ucf:52919
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0001859

Title: Analysis of frequency selective surfaces with ferrite substrates.
Creator: Liu, Youcheng, Christodoulou, Christos, Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; Frequency selective surfaces (FSS) have numerous applications in several microwave and optical systems. In this work, instead of traditional dielectric substrates, ferrite substrates are used under different dc bias conditions.
Date Issued: 1996
Identifier: CFR0000784, ucf:52927
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0000784

Title: Numerical, image, and signal processing algorithms applied to radar rainfall estimation.
Creator: Lane, John Eugene, Kasparis, Takis, Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; The main focus of this dissertation research has been to develop and analyze methods of rain gauge and radar correlation for the purpose of optimizing rainfall estimates.
Date Issued: 2001
Identifier: CFR0000782, ucf:52926
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0000782

Title: Synthesis of numerical integrators for the real-time digital simulation of continuous systems.
Creator: Panzitta, Michael James, Klee, Harold I., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; Real-time digital simulation is a powerful means for engineers and scientists in government, industry, and academia to perform research and training as well as serving as a basis for many commercial applications. Due to the special constraints imposed by digitally simulating continuous systems in real time, however, many of these systems either require costly high-speed components or are unable to provide suitable performance...
Show moreUniversity of Central Florida College of Engineering Thesis; Real-time digital simulation is a powerful means for engineers and scientists in government, industry, and academia to perform research and training as well as serving as a basis for many commercial applications. Due to the special constraints imposed by digitally simulating continuous systems in real time, however, many of these systems either require costly high-speed components or are unable to provide suitable performance characteristics using affordable computers. This dissertation describes a new technique for the synthesis of numerical integrators specifically designed for the real-time digital simulation of continuous systems. This methodology is based upon the fact that the state derivatives in a simulation model typically have a significantly limited bandwidth. This information is exploited to improve the efficiency of numerical integrators by selecting the coefficients of a general-form integrator such that it approximates an ideal integrator over the limited frequency spectrum of the state derivative.
Show less
Date Issued: 1994
Identifier: CFR0001376, ucf:52923
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0001376

Title: Counterpropagation neural network detection of visual primitives.
Creator: Johnson, Cynthia Lynn, Myler, Harley R., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; Psychological testing has shown that there is an early preattentive stage in the human visual system. At this level, simple features and properties of objects known as visual primitives are deteched spatially in parallel by groupings of cells in the visual cortex known as feature maps. In order to study this preattentive stage in a machine vision system, the biologically inspired, highly parallel architecture of the artificial...
Show moreUniversity of Central Florida College of Engineering Thesis; Psychological testing has shown that there is an early preattentive stage in the human visual system. At this level, simple features and properties of objects known as visual primitives are deteched spatially in parallel by groupings of cells in the visual cortex known as feature maps. In order to study this preattentive stage in a machine vision system, the biologically inspired, highly parallel architecture of the artificial neural network shows great promise. This paper describes how the unique architecture of the counterpropagation neural network was used to simulate the feature maps which detect visual primitives in the human visual system. The results of the research showed that artificial neural networks are able to reproduce the function of the feature maps with accuracy. The counterpropagation network was able to reproduce the feature maps as theorized, however, future research might investigate the abilities of other neural network algorithms in this area. Development of a method for combining the results of feature maps in a simulation of full scale early vision is also a topic for future research that would benefit from the results reported here.
Show less
Date Issued: 1990
Identifier: CFR0008146, ucf:52942
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0008146

Title: Closure of unlined landfills.
Creator: Westhorp, Brenda J., Reinhart, Debra R., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis
Date Issued: 1990
Identifier: CFR0008145, ucf:52954
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0008145

Title: Measuring and compensating for transport delay in real-time interactive driving simulation.
Creator: Dumas, Joseph D., Klee, Harold I., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; Real-time, man-in-the-loop simulators are important tools for operator training as well as human performance research. Simulator implementation using digital computers offers many important advantages but may also cause problems. One of the most significant and troublesome artifacts of digital computer simulation is the presence of transport delays in the operator/vehicle control loop. Transport delays have been shown to destabilize...
Show moreUniversity of Central Florida College of Engineering Thesis; Real-time, man-in-the-loop simulators are important tools for operator training as well as human performance research. Simulator implementation using digital computers offers many important advantages but may also cause problems. One of the most significant and troublesome artifacts of digital computer simulation is the presence of transport delays in the operator/vehicle control loop. Transport delays have been shown to destabilize the system, resulting in poorer control of the simulated vehicle. They may also contribute to an increased likelihood of simulator sickness in human operators. Therefore, it is desirable to be able to quantify simulator transport delays and to compensate the system in such a way that delay effects on operator performance and well-being are minimized. The research presented in this dissertation involved the measurement of simulator transport delay using two different methods: a time-domain approach involving the detection of a response to a simulated step control input, and a frequency-domain approach involving the measurement of phase shift from a simulated sinusoidal input. Algorithmic compensators (digital filters) were developed to provide phase lead to counteract the system transport delay. Two compensators designed using approaches previously described in the literature canceled out delay reasonably well; however, a new compensator design developed by the author provided more nearly ideal phase performance without introducing unwanted side effects such as visual jitter. The transport delay measurement and compensation techniques were applied to a low-cost, real-time interactive automobile driving simulator developed at the University of Central Florida. The investigations using both measurement techniques revealed that a substantial amount of delay was present in the system. The three delay compensators implemented in the simulator were found (by reapplication of the frequency-domain or steady-state delay measurement technique) to operate approximately as designed. Finally, a driver-in-the-loop experiment was conducted to assess the effect of delay compensation on driver/vehicle performance. While the small size of the experiment allowed no definite conclusions to be drawn regarding the efficacy of compensation, trends in the data were generally indicative of better performance with compensation.
Show less
Date Issued: 1993
Identifier: CFR0000192, ucf:52933
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0000192

Title: Design and applications of volume holographic optical elements.
Creator: Dunn, Steven C., Moharam, M.G., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; Volume gratings were studied both theoretically and experimentally in order to design and analyze practical volume holographic optical elements. The diffraction of finite (Gaussian) beams by transmission gratings is investigated.
Date Issued: 2001
Identifier: CFR0000781, ucf:52930
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0000781

Title: Finite impulse response utilizing the principles of superposition.
Creator: Carter, Scott Edward, Malocha, Donald C., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; Window functions have been greatly utilized in the synthesis of finite impulse response (FIR) filters implemented using surface acoustic wave (SAW) devices. The critical parameter in any FIR design in the impulse response length, which must be optimized for the given design specifications in order to reduce the size of each device. To this end, many design algorithms have been introduced such as Remez exchange, linear programming,...
Show moreUniversity of Central Florida College of Engineering Thesis; Window functions have been greatly utilized in the synthesis of finite impulse response (FIR) filters implemented using surface acoustic wave (SAW) devices. The critical parameter in any FIR design in the impulse response length, which must be optimized for the given design specifications in order to reduce the size of each device. To this end, many design algorithms have been introduced such as Remez exchange, linear programming, and least mean squares. A new algorithm has been derived which is efficient and accurate for the design of arbitrary filter specifications requiring less computations than the current algorithms. The FIR design is applicaable to general SAW filter design and allows two weighted transducers to be designed in a near optimal method without the need to perform zero aplitting of de-convolution. The thesis first provides the definition of the window functions used for the design process. Then the overview of the design process is discussed using a flowchart of the modeling program for designing and FIR without tranducer separation and sample simulation is presented. Next, the effects of monotonically increasing sidelobes on the transition bandwidth are discussed. This is followed by a discussion of the addition of arbitary phase to the filter design requirements. Next, the separation of the response into a two transducer design utilizing the two window function series is explained. Finally, the results are discussed and compared with other design techniques.
Show less
Date Issued: 1995
Identifier: CFR0000186, ucf:52937
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0000186

Title: Semantic correlation of behavior for the interoperability of heterogeneous simulations.
Creator: Dean, Christopher James, Gonzalez, Avelino J., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; A desirable goal of military simulation training is to provide large scale or joint exercises to train personnel at higher echelons. To help meet this goal, many of the lower echelon combatants must consist of computer generated forces with some of these echelons composed of units from different simulations. The object of the research described is to correlate the behaviors of entities in different simulations so that they can...
Show moreUniversity of Central Florida College of Engineering Thesis; A desirable goal of military simulation training is to provide large scale or joint exercises to train personnel at higher echelons. To help meet this goal, many of the lower echelon combatants must consist of computer generated forces with some of these echelons composed of units from different simulations. The object of the research described is to correlate the behaviors of entities in different simulations so that they can interoperate with one another to support simulation training. Specific source behaviors can be translated to a form in terms of general behaviors which can then be correlated to any desired specific destination simulation behavior without prior knowledge of the pairing. The correlation, however, does not result in 100% effectiveness because most simulations have different semantics and were designed for different training needs. An ontology of general behaviors and behavior parameters, a database of source behaviors written in terms of these general behaviors with a database of destination behaviors. This comparison is based upon the similarity of sub-behaviors and the behavior parameters. Source behaviors/parameters may be deemed similar based upon their sub-behaviors or sub-parameters and their relationship (more specific or more general) to destination behaviors/parameters. As an additional constraint for correlation, a conversion path from all required destination parameters to a souce parameter must be found in order for the behavior to be correlated and thus executed. The length of this conversion path often determines the similarity for behavior parameters, both source and destination. This research has shown, through a set of experiments, that heuristic metrics, in conjunction with a corresponding behavior and parameter ontology, are sufficient for the correlation of heterogeneous simulation behavior. These metrics successfully correlated known pairings provided by experts and provided reasonable correlations for behaviors that have no corresponding destination behavior. For different simulations, these metrics serve as a foundation for more complex methods of behavior correlation.
Show less
Date Issued: 1996
Identifier: CFR0008169, ucf:53071
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0008169

Title: Emissions of hexavalent chromium from hard chromium plating operations.
Creator: Hall, Mitchell Scott, Wayson, Roger L., Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; This research addressess emissions of hexavalent chromium mist from hard chromium electroplating operations. Most of these emissions are typically captured by a ventilation stack and directed to a pollution control device; those which escape capture are called fugitive emissions. Releases of toxic materials such as hexavalent chromium must be reported annually to the Environmental Protection Agency (EPA) under provisions of the...
Show moreUniversity of Central Florida College of Engineering Thesis; This research addressess emissions of hexavalent chromium mist from hard chromium electroplating operations. Most of these emissions are typically captured by a ventilation stack and directed to a pollution control device; those which escape capture are called fugitive emissions. Releases of toxic materials such as hexavalent chromium must be reported annually to the Environmental Protection Agency (EPA) under provisions of the Superfund Amendments and Reauthorization Act (SARA) Title III of 1986 via the Toxic Release Inventory (TRI), Form R. The objectives were: (1) to provide estimates of fugitive hexavalent chromium emissions for the completion of Form R; and (2) to develop a predictive model for stack and fugitive emissions versus process and ventilation parameters. The database for stack emissions included published results from EPA studies. Fugitive release data were generated by field characterization at two operating facilities. Supplemental data for stack releases were also obtained during this field activity. The fugitive releases were documented to represent a small portion of the total atmospheric discharge; in most instances, the fugitive releases were less than the detection capability of the smapling/analytical protocols. Stack releases were successfully correlated with a measure of production activity (ampere-hours), production capacity (mass of chromium in the process bath), tank dimensions (plating bath surface area), and ventilation efficiency (ventilation slot area). This effort was supported by the EPA in the form of a cooperative agreement with the American Electropaters and Surface Finishers Society (AESF).
Show less
Date Issued: 1992
Identifier: CFR0008174, ucf:53062
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0008174

Title: Design and construction of maintainable knowledge bases through effective use of entity-relationship modeling techniques.
Creator: Pike, William Yancey, Khajenoori, Soheil, Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; The use of an accepted logical database design tool, Entity-Relationship Diagrams (E-RD), is explored as a method by which conceptual and pseudo-conceptual knowledge bases may be designed. Extensions to Peter Chen's classic E-RD method which can model knowledge structure used by knowledge-based applications are explored. The use of E-RDs to design knowledge bases is proposed as a two-stage process. In the first stage, and E-RD,...
Show moreUniversity of Central Florida College of Engineering Thesis; The use of an accepted logical database design tool, Entity-Relationship Diagrams (E-RD), is explored as a method by which conceptual and pseudo-conceptual knowledge bases may be designed. Extensions to Peter Chen's classic E-RD method which can model knowledge structure used by knowledge-based applications are explored. The use of E-RDs to design knowledge bases is proposed as a two-stage process. In the first stage, and E-RD, termed the Essential E-RD, is developed of the realm of the problem or enterprise being modeled. The Essential E-RD is completely independent of any knowledge representation model (KRM) and is intended for the understanding of the underlying conceptual entities and relationships in the domain of interest. The second stage of the proposed design process consists of expanding the Essential E-RD. The resulting E-RD, termed the Implementation E-RD, is a network of E-RD-modeled KRM constructs and will provide a method by which the proper KRM may be chosen and the knowledge base may be maintained. In some cases, the constructs of the Implementation E-RD may be mapped directly to a physical knowledge base. Using the proposed design tool will aid in both the development of the knowledge base and its maintenance. The need for building maintainable knowledge bases and problems often encountered during knowledge base construction will be explored. A case study is presented in which this tool is used to design a knowledge base. Problems avoided by the use of this method are highlighted, as are advantages the method presents to the maintenance of the knowledge base. Finally, a critique of the ramifications of this research is presented, as well as needs for future research.
Show less
Date Issued: 1993
Identifier: CFR0008173, ucf:53064
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0008173

Title: Analysis of threaded joint behavior in an airbag module assembly.
Creator: Chemat, Rustam, Hagedoorn, A. Henry, Engineering
Abstract / Description: University of Central Florida College of Engineering Thesis; While some of think of our cars as simply "buckets of bolts", the proper design choices, applications, and assemblies of threaded fasteners/bolted joints play critical roles in automobile safety. Supplemental Restraint Systems (SRS), more commonly known as airbags, help prevent vehicle occupants from being thrown forward into the dashboard or windshield in the event of a collision. The components comprising the airbag, the inflator,...
Show moreUniversity of Central Florida College of Engineering Thesis; While some of think of our cars as simply "buckets of bolts", the proper design choices, applications, and assemblies of threaded fasteners/bolted joints play critical roles in automobile safety. Supplemental Restraint Systems (SRS), more commonly known as airbags, help prevent vehicle occupants from being thrown forward into the dashboard or windshield in the event of a collision. The components comprising the airbag, the inflator, the backing plate, and the cover are connected to each other, and to the vehicle, through a series of threaded fasteners. Proper and timely deployment of the airbag depends largely on the selection of suitable threaded fasteners at the design stage, appropriate fastener application, and strict adherence to the module assembly process. Selecting suitable fasteners and applying fasteners appropriately requires and understanding of basic fastener concepts: thread definitions, fastener loading terms, stress and strength, and joint failure modes. Knowledge of torque, preload, torque equations, and torque control also is necessary before proper selection and application can occur. The Case Study examines a drivers' side airbag module currently used on a vehicle marketed in the United States and, employing applicable design equations, determines 1.) if the design selction of the threaded fasteners is appropriate, 2.) how the threaded fasteners behave during and after airbag assembly, and during airbag deployment, and 3.) the potential problems arising from loose or missing fasteners. The thesis concludes the design and selection of the fasteners used in the airbag module concurs with the basic principles of threaded joints. Through the cases selected for the modules, the thesis generates several conditions that must be met to prevent joint failures. It is proposed that this research be used to further determine both the design selection of threaded fasteners and the assembly processes of automotive airbag manufacturing.
Show less
Date Issued: 1996
Identifier: CFR0010870, ucf:53054
Format: Document (PDF)
PURL: http://purl.flvc.org/ucf/fd/CFR0010870

Title: The effect of varying temperature, flux and pretreatment on the microfiltration of Lake Michigan water.
Creator: 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 48Â°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: 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: 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: Color image enhancement using both chromatic and luminance components.
Creator: 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: 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: 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

Engineering -- Dissertations (40)	+ -
Academic (39)	+ -
Dissertations (39)	+ -
Academic -- Engineering (38)	+ -
Academic -- Engineering -- FOFT (1)	+ -

Academic -- FOFT (1)	+ -
Algorithms (1)	+ -
Antennas (Electronics) (1)	+ -
Asynchronous circuits (1)	+ -
Asynchronous circuits -- Design and construction (1)	+ -
Computer networks (1)	+ -
Computer simulation (1)	+ -
Computer software -- Reusability (1)	+ -
DC to DC converters (1)	+ -
Database management (1)	+ -
Digital video (1)	+ -
Electric current rectifiers (1)	+ -
Electric power -- Conservation (1)	+ -
Graph theory (1)	+ -
Holography (1)	+ -
Image processing -- Digital techniques (1)	+ -
Information storage and retrieval systems (1)	+ -
Ionosphere (1)	+ -
Natural language processing (Computer science) (1)	+ -
Neural networks (Computer science) (1)	+ -
Packet switching (Data transmission) (1)	+ -
Parsing (Computer grammar) (1)	+ -
Power electronics (1)	+ -
Product management -- Cost effectiveness (1)	+ -
Quality of products -- Cost effectiveness (1)	+ -

Engineering (28)	+ -
Engineering and Computer Science (11)	+ -
Batarseh, Issa (3)	+ -
Malocha, Donald C. (3)	+ -
Carter, Scott Edward (2)	+ -

Dietz, John D. (2)	+ -
Klee, Harold I. (2)	+ -
Abdalla, Ayman Mahmoud (1)	+ -
Anderson, Robert K (1)	+ -
Batarseh, Issa E. (1)	+ -
Bishop, Carlton Delos (1)	+ -
Boreman, Glenn D. (1)	+ -
Burridge, Michael J. (1)	+ -
Chemat, Rustam (1)	+ -
Christodoulou, Christos (1)	+ -
Christodoulou, Christos G. (1)	+ -
DeMara, Ronald (1)	+ -
Dean, Christopher James (1)	+ -
Deo, Narsingh (1)	+ -
Di, Jia (1)	+ -
Dumas, Joseph D. (1)	+ -
Dunn, Steven C. (1)	+ -
Engineering and Computer Sciences (1)	+ -
Ferreira, Labiche (1)	+ -
Gelenbe, Erol (1)	+ -
Gomez, Fernando (1)	+ -
Gonzalez, Avelino (1)	+ -
Gonzalez, Avelino J. (1)	+ -
Gonzalez, Francisco Javier (1)	+ -
Gu, Wei (1)	+ -

Search In

Pages

Pages

Sort Results By:

Narrow results by:

Topical Subject

Collection

Type of Resource

Language

Creator

Format

Owner