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- Title
- A COMPARATIVE ANALYSIS OF GREEN ROOF DESIGNS INCLUDING DEPTH OF MEDIA, DRAINAGE LAYER MATERIALS, AND POLLUTION CONTROL MEDIA.
- Creator
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Kelly, Matt, Cooper, C. David, University of Central Florida
- Abstract / Description
-
Population growth has lead to an increase in development and impervious areas in urban settings. Post-development conditions cause several problems for stormwater management such as limited space for stormwater storage systems and the conveyance of pollution picked up by runoff to near by water bodies. Green Roofs with cisterns have been shown to attenuate the peak flow of storm events and reduce the pollution load leaving a site and entering nearby water bodies. The purpose of this research...
Show morePopulation growth has lead to an increase in development and impervious areas in urban settings. Post-development conditions cause several problems for stormwater management such as limited space for stormwater storage systems and the conveyance of pollution picked up by runoff to near by water bodies. Green Roofs with cisterns have been shown to attenuate the peak flow of storm events and reduce the pollution load leaving a site and entering nearby water bodies. The purpose of this research is to expand the available research data on green roofs with cisterns by investigating the water quality and hydrology effects of different green roof designs including depth of media, an additional pollution control layer beneath the growth media, and different drainage layer materials. Furthermore, a comparison study is performed on the cistern water quality, direct filtrate water quality, and control roof filtrate water quality. Results show that phosphorus concentrations are lower when using a pollution control layer beneath the growing media, and that evapotransporation and filtrate factor values from the 4-inch media and the 8-inch media are approximately equal for one year. However, hydrograph results show that the 8-inch media design has a lower peak flow and longer attenuation when compared to the 4-inch media design for a single storm event. Furthermore, the drainage layer material has no significant effect on the water quality or hydrology of the green roof discharge. The data also emphasizes the importance and effectiveness of the incorporation of a cistern into a green roof system.
Show less - Date Issued
- 2008
- Identifier
- CFE0002107, ucf:47552
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002107
- Title
- A COMPREHENSIVE MULTI-FACETED APPROACH FOR SIMULTANEOUSLY ANALYZING ORGANIZATIONAL PERFORMANCE MEASURES ESSENTIAL FOR COMPANY SUCCESS IN MANUFACTURING ENTERPRISES.
- Creator
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Ferreras, Ana, Crumpton-Young, Lesia, University of Central Florida
- Abstract / Description
-
Profit, ergonomics, safety, employee morale, quality, efficiency, and productivity are critical components that greatly impact company success within manufacturing organizations. Therefore, it is essential that a valid and reliable systematic approach that encompasses all of these factors be developed for use by top management in today's rapidly changing manufacturing environment. Organizational-level decisions made based upon a single goal or narrow perspective that only considers one of...
Show moreProfit, ergonomics, safety, employee morale, quality, efficiency, and productivity are critical components that greatly impact company success within manufacturing organizations. Therefore, it is essential that a valid and reliable systematic approach that encompasses all of these factors be developed for use by top management in today's rapidly changing manufacturing environment. Organizational-level decisions made based upon a single goal or narrow perspective that only considers one of the aforementioned components, such as profit, while ignoring others, such as employee morale, have proven harmful to the long term viability and success of manufacturing companies. Often organizational leaders are not adequately equipped to consider multiple factors that are pertinent to company success due to the complexity associated with considering a large number of organizational variables and the lack of quantitative tools and techniques to assist in this process. Thus, valid, reliable and readily available tools, methods, and techniques for integrating into decision making multiple components of profit, ergonomics, safety, employee morale, quality, efficiency, and productivity are highly needed in today's complex manufacturing business environment. This research responds to the need to develop quantitative models by creating a company success index. This index was developed using an approach to analyze and evaluate multiple factors at the strategic, tactical, and operational levels of an organization that are essential to achieve company success in manufacturing enterprises. The resulting company success index model was validated using information on market share (Specificity = 0%, Sensitivity & Accuracy = 87.5%). Future research related to this topic area should include additional studies to expand upon model validation and verification techniques.
Show less - Date Issued
- 2008
- Identifier
- CFE0002173, ucf:47504
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002173
- Title
- REVERSION OF POLY-PHOSPHATES TO ORTHO-PHOSPHATES IN WATER DISTRIBUTION SYSTEMS.
- Creator
-
shekhar, avinash, taylor, james, University of Central Florida
- Abstract / Description
-
Orthophosphates and polyphosphates are rarely present at significant levels in raw water source but are purposefully added to the water in various forms to inhibit corrosion, iron oxidation (red water), or calcium carbonate precipitation (scale formation). Orthophosphates serve as building blocks for polyphosphates, which includes structures in linear chain, branched chains (metaphosphate) and "glassy" polyphosphate polymers. The advantage of polyphosphates over ortho phosphates lies in the...
Show moreOrthophosphates and polyphosphates are rarely present at significant levels in raw water source but are purposefully added to the water in various forms to inhibit corrosion, iron oxidation (red water), or calcium carbonate precipitation (scale formation). Orthophosphates serve as building blocks for polyphosphates, which includes structures in linear chain, branched chains (metaphosphate) and "glassy" polyphosphate polymers. The advantage of polyphosphates over ortho phosphates lies in the fact that they slowly revert to orthophosphates and thus provide corrosion inhibition action over longer period of time in distribution systems. A study was completed for Tampa Bay Water on water distribution systems in a changing water quality environment. Blended orthophosphates was used as one of the corrosion inhibitors to study its effects on metal release and thus justify its application in comparison to other corrosion inhibitors like orthophosphates, zinc orthophosphates and silicates. This work focuses on the study of reversion of polyphosphates to ortho phosphates. A first-order model was developed that quantifies reversion as a function of the hydraulic residence time and initial poly phosphate concentration. The same model was used in two different forms – one for the hybrid lines and the other for single material lines. The results from single material lines (estimated by a non linear least square regression using ANOVA) showed that the reversion rate was highest for galvanized pipe followed by unlined cast iron, lined cast iron and the lowest rate in PVC. The first-order reversion rate constant in PVC was almost two log orders less than galvanized line. A high first-order rate constant for the galvanized pipe could be attributed to a rougher surface, large surface area, reaction with the wall surface, pipe material or a combination of these effects. The results from the hybrid PDSs (estimated by an algebraic manipulation of the first-order reaction) substantially agree with the results obtained from the single material lines, with the exception of the PVC material. The data from the hybrid lines confirms that the reversion rate constant is greatest for exposure to galvanized pipe materials, but the hybrid data indicate that the rate constant associated with PVC is somewhat larger than the constants determined for either LCI or UCI. Once an overall first-order rate expression was established, efforts were made to find a relation between polyphosphate reversions with bulk water quality. None of the major water quality parameters were found to significantly affect the reversion. This observation may be attributable to a similar water quality over the study duration. A positive correlation was found between first-order reversion rate constant and temperature. An empirical equation (modified Arrhenius equation) that relates the first-order reversion rate constant with temperature was developed that showed a strong sensitivity to temperature. The results from this study could be used to predict the stability of polyphosphates in distribution systems with varying pipe materials and temperature.
Show less - Date Issued
- 2007
- Identifier
- CFE0001832, ucf:47350
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001832
- Title
- IMPACT OF ZINC ORTHOPHOSPHATE INHIBITOR ONDISTRIBUTION SYSTEM WATER QUALITY.
- Creator
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Guan, Xiaotao, Taylor, James, University of Central Florida
- Abstract / Description
-
This dissertation consists of four papers concerning impacts of zinc orthophosphate (ZOP) inhibitor on iron, copper and lead release in a changing water quality environment. The mechanism of zinc orthophosphate corrosion inhibition in drinking water municipal and home distribution systems and the role of zinc were investigated. Fourteen pilot distribution systems (PDSs) which were identical and consisted of increments of PVC, lined cast iron, unlined cast iron and galvanized steel pipes were...
Show moreThis dissertation consists of four papers concerning impacts of zinc orthophosphate (ZOP) inhibitor on iron, copper and lead release in a changing water quality environment. The mechanism of zinc orthophosphate corrosion inhibition in drinking water municipal and home distribution systems and the role of zinc were investigated. Fourteen pilot distribution systems (PDSs) which were identical and consisted of increments of PVC, lined cast iron, unlined cast iron and galvanized steel pipes were used in this study. Changing quarterly blends of finished ground, surface and desalinated waters were fed into the pilot distribution systems over a one year period. Zinc orthophosphate inhibitor at three different doses was applied to three PDSs. Water quality and iron, copper and lead scale formation was monitored for the one year study duration. The first article describes the effects of zinc orthophosphate (ZOP) corrosion inhibitor on surface characteristics of iron corrosion products in a changing water quality environment. Surface compositions of iron surface scales for iron and galvanized steel coupons incubated in different blended waters in the presence of ZOP inhibitor were investigated using X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM) / Energy Dispersive X-ray Spectroscopy (EDS). Based on surface characterization, predictive equilibrium models were developed to describe the controlling solid phase and mechanism of ZOP inhibition and the role of zinc for iron release. The second article describes the effects of zinc orthophosphate (ZOP) corrosion inhibitor on total iron release in a changing water quality environment. Development of empirical models as a function of water quality and ZOP inhibitor dose for total iron release and mass balances analysis for total zinc and total phosphorus data provided insight into the mechanism of ZOP corrosion inhibition regarding iron release in drinking water distribution systems. The third article describes the effects of zinc orthophosphate (ZOP) corrosion inhibitor on total copper release in a changing water quality environment. Empirical model development was undertaken for prediction of total copper release as a function of water quality and inhibitor dose. Thermodynamic models for dissolved copper based on surface characterization of scale that were generated on copper coupons exposed to ZOP inhibitor were also developed. Surface composition was determined by X-ray Photoelectron Spectroscopy (XPS). The fourth article describes the effects of zinc orthophosphate (ZOP) corrosion inhibitor on total lead release in a changing water quality environment. Surface characterization of lead scale on coupons exposed to ZOP inhibitor by X-ray Photoelectron Spectroscopy (XPS) was utilized to identify scale composition. Development of thermodynamic model for lead release based on surface analysis results provided insight into the mechanism of ZOP inhibition and the role of zinc.
Show less - Date Issued
- 2007
- Identifier
- CFE0001931, ucf:47453
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001931
- Title
- THE EFFECT OF FREE CHLORINE AND CHLORAMINES ON LEAD RELEASE IN A DISTRIBUTION SYSTEM.
- Creator
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Vasquez, Ferdinand, Taylor, James, University of Central Florida
- Abstract / Description
-
Total lead release in drinking water in the presence of free chlorine and chloramine residuals was investigated in field, laboratory and fundamental investigations for finished waters produced from ground (GW), surface (SW), saline (RO) and blended (B) sources. Field investigations found more total lead was released in the presence of chloramines than in the presence of free chlorine for RO and blended finished waters; however, there were no statistical differences in total lead release to...
Show moreTotal lead release in drinking water in the presence of free chlorine and chloramine residuals was investigated in field, laboratory and fundamental investigations for finished waters produced from ground (GW), surface (SW), saline (RO) and blended (B) sources. Field investigations found more total lead was released in the presence of chloramines than in the presence of free chlorine for RO and blended finished waters; however, there were no statistical differences in total lead release to finished GW and SW. Laboratory measurements of finished waters oxidation-reduction potential (ORP) were equivalent by source and were not affected by the addition of more than 100 mg/L of sulfates or chlorides, but were significantly higher in the presence of free chlorine relative to chloramines. Development of Pourbaix diagrams revealed the PbO2 was the controlling solid phase at the higher ORP in the presence of free chlorine and Pb3(CO3)2(OH)2(s) (hydrocerussite) was the controlling solid phase in the presence of chloramines at the lower ORP, which mechanistically accounted for the observed release of total lead as PbO2 is much less soluble than hydrocerussite. The lack of differences in total lead release to finished GW and SW was attributed to differences in water quality and intermittent behavior of particulate release from controlling solid films.
Show less - Date Issued
- 2005
- Identifier
- CFE0000533, ucf:46427
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000533
- Title
- QOS IN COGNITIVE PACKET NETWORKS: ADAPTIVE ROUTING, FLOW AND CONGESTION CONTROL.
- Creator
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Su, Pu, Gelenbe, Erol, University of Central Florida
- Abstract / Description
-
With the emergence of various applications that have different Quality of Service (QoS) requirements, the capability of a network to support QoS becomes more and more important and necessary. This dissertation explores QoS in Cognitive Packet Networks (CPN) by using adaptive routing, flow and congestion control. We present a detailed description and analysis of our proposed routing algorithms based on single and multiple QoS constraints. An online estimation of packet loss rate over a path is...
Show moreWith the emergence of various applications that have different Quality of Service (QoS) requirements, the capability of a network to support QoS becomes more and more important and necessary. This dissertation explores QoS in Cognitive Packet Networks (CPN) by using adaptive routing, flow and congestion control. We present a detailed description and analysis of our proposed routing algorithms based on single and multiple QoS constraints. An online estimation of packet loss rate over a path is introduced. We implement and evaluate the adaptive routing scheme in an experimental CPN test-bed. Our experiments support our claims that the users can achieve their desired best-effort QoS through this routing scheme. We also propose a QoS-based flow and congestion control scheme that is built in the transport layer and specially designed to work with CPN to support users' QoS while remaining friendly to TCP. Theoretical models and experimental analysis are presented. Finally we experimentally demonstrate that the proposed flow and congestion control scheme can effectively control the input flows, react to the congestion and work with our proposed adaptive routing scheme to achieve users' QoS.
Show less - Date Issued
- 2005
- Identifier
- CFE0000813, ucf:46685
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0000813
- Title
- INVESTIGATING THE MECHANISMS THAT DRIVE IMPLICIT COORDINATION IN TEAMS.
- Creator
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Hoeft, Raegan, Jentsch, Florian, University of Central Florida
- Abstract / Description
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The purpose of this study was to empirically test the oft-noted hypothesis that shared mental models lead to implicit coordination. Specifically, this dissertation investigated the underlying mechanisms of implicit coordination and how different aspects of shared mental models affect the process. The research questions tested in this study were (a)how perceptions of sharedness affect the initiation of implicit coordination, (b) how actual levels of sharedness affect the process of implicit...
Show moreThe purpose of this study was to empirically test the oft-noted hypothesis that shared mental models lead to implicit coordination. Specifically, this dissertation investigated the underlying mechanisms of implicit coordination and how different aspects of shared mental models affect the process. The research questions tested in this study were (a)how perceptions of sharedness affect the initiation of implicit coordination, (b) how actual levels of sharedness affect the process of implicit coordination, and (c) how quality of task mental models affects successful implicit coordination. Sixty same-gender, two-person teams engaged in a complex military reconnaissance planning task in which the team members were required to work together by exchanging information to plan routes for one unmanned aerial vehicle (UAV) and one unmanned ground vehicle (UGV). The results provided partial support for the influence of different facets of shared mental models on the process of implicit coordination. Specifically, individual mental model quality, not perceptions of sharedness or actual mental model sharedness, was the biggest predictor of the initiation of implicit coordination. Additionally, perceptions of sharedness and actual mental model sharedness interacted with one another, such that teams in mismatched conditions (high perceptions of sharedness but low actual sharedness [false consensus], or low perceptions of sharedness and high actual sharedness, [pluralistic ignorance]) tended to increase their communications. The implications and recommendations for future research on implicit coordination and shared mental models are discussed. Additionally, the implications for operators of unmanned vehicles are also discussed.
Show less - Date Issued
- 2006
- Identifier
- CFE0001181, ucf:46857
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0001181
- Title
- SPIRITUAL CARE INTERVENTIONS TO IMPROVE THE QUALITY OF LIFE IN PATIENTS WITH ADVANCED CANCER RECEIVING PALLIATIVE CARE.
- Creator
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Ballen-Sanchez, Maria, Conner, Norma, University of Central Florida
- Abstract / Description
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Title: Spiritual Care Interventions and Quality of Life in Cancer Patients Receiving Palliative Care Background: Despite the evidence supporting spiritual care in nursing and an increased quality of life among patients, patients feel that their spiritual needs are not being supported by medical professionals. Nurses agree that the role they play is significant in addressing the needs of cancer patients; however, they feel that they lack the knowledge for addressing spirituality concerns at...
Show moreTitle: Spiritual Care Interventions and Quality of Life in Cancer Patients Receiving Palliative Care Background: Despite the evidence supporting spiritual care in nursing and an increased quality of life among patients, patients feel that their spiritual needs are not being supported by medical professionals. Nurses agree that the role they play is significant in addressing the needs of cancer patients; however, they feel that they lack the knowledge for addressing spirituality concerns at the end of life. The purpose of this study is to identify spiritual care interventions that nurses can implement to improve quality of life (QOL) in patients with advanced cancer receiving palliative care. Method: This literature review consisted of articles retrieved from several databases, including CINAHL, PubMED, and PsychINFO , PsychARTICLES, ATLA Religion databases using the key words "cancer*" and "quality of life" "therapeutic communication", "spirit* therapy", "relaxation therapy", and "self-care". Inclusion criteria consisted of research conducted after the year 2000, peer reviewed work and research studies written in the English language. Results: Results from this literature review include recommended nursing interventions that provide spiritual care to patients with advanced cancer receiving palliative care for the purpose of improved quality of life. Spiritual care interventions identified in this study include Meaning Centered Group Psychotherapy (MCGP), Supportive Group Psychotherapy (SGP), mental relaxation, mental images, TM, art therapy, socializing, communicative acts, aromatherapy, massage, exercise, hatha yoga, meditation, and activities such as gardening, watching TV, resting/sleeping and socializing.
Show less - Date Issued
- 2012
- Identifier
- CFH0004245, ucf:44925
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004245
- Title
- RISK FACTORS IDENTIFIED IN COLLEGE STUDENTS EXHIBITING SOCIAL PHOBIA.
- Creator
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Wallace, Kasie, McConnell, Daniel, University of Central Florida
- Abstract / Description
-
College life is a unique experience in the life of many young adults that presents many challenges for which they might not be prepared, including living away from home and adapting to a new social and academic environment. In particular, these experiences may be particularly adverse for students with social phobia and may be predictors of academic and social problems, and may even predict dropout. The purpose of the present research is to identify possible connections between socially phobic...
Show moreCollege life is a unique experience in the life of many young adults that presents many challenges for which they might not be prepared, including living away from home and adapting to a new social and academic environment. In particular, these experiences may be particularly adverse for students with social phobia and may be predictors of academic and social problems, and may even predict dropout. The purpose of the present research is to identify possible connections between socially phobic tendencies and the social, emotional, and overall well-being of college students. Social phobia itself is an unnecessary and overwhelming fear of being scrutinized by others (National Institute of Mental Health 2009). By implementing the use of four psychological tests: the Social Phobia and Anxiety Inventory, Positive and Negative Affect Schedule, College Affiliation Questionnaire, and Life Orientation Test, this research sought to investigate the correlations existing between college students' self-reports on these measures through the use of the UCF Sona system. Students' personal characteristics and demographics were also examined correlationally along with their self-reports on all four measures. A total of 165 participants were used in this study. After gathering descriptive statistics from each test and their demographics, correlations were run between the four tests and then between demographic information and tests. The results showed social phobia having a positive correlation with negative affect and a negative relationship with positive affect. In turn, negative emotion was correlated with a lowered overall life orientation and a more pessimistic mindset. No strong correlations were identified between psychological tests and student characteristics as was previously thought. Overall, there are definite indicators that social anxiety has a negative impact on one's quality of life and emotions, however, more research needs to be done with more diverse sampling and different methodology to see if there is a link between particular student characteristics and prevalence rates of social anxiety within those characteristic subsets.
Show less - Date Issued
- 2014
- Identifier
- CFH0004562, ucf:45165
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFH0004562
- Title
- AN INTEGRATED HYDROLOGY/HYDRAULIC AND WATER QUALITY MODEL FOR WATERSHED-SCALE SIMULATIONS.
- Creator
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Wang, Cheng, Yeh, Gour-Tsyh, University of Central Florida
- Abstract / Description
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This dissertation presents the design of an integrated watershed model, WASH123D version 3.0, a first principle, physics-based watershed-scale model of integrated hydrology/hydraulics and water quality transport. This numerical model is comprised of three modules: (1) a one-dimensional (1-D) simulation module that is capable of simulating separated and coupled fluid flow, sediment transport and reaction-based water quality transport in river/stream/canal networks and through control...
Show moreThis dissertation presents the design of an integrated watershed model, WASH123D version 3.0, a first principle, physics-based watershed-scale model of integrated hydrology/hydraulics and water quality transport. This numerical model is comprised of three modules: (1) a one-dimensional (1-D) simulation module that is capable of simulating separated and coupled fluid flow, sediment transport and reaction-based water quality transport in river/stream/canal networks and through control structures; (2) a two-dimensional (2-D) simulation module, capable of simulating separated and coupled fluid flow, sediment transport, and reactive biogeochemical transport and transformation in two-dimensional overland flow systems; and (3) a three-dimensional (3-D) simulation module, capable of simulating separated and coupled fluid flow and reactive geochemical transport and transformation in three-dimensional variably saturated subsurface systems. The Saint Venant equation and its simplified versions, diffusion wave and kinematic wave forms, are employed for surface fluid flow simulations and the modified Richards equation is applied for subsurface flow simulation. The reaction-based advection-dispersion equation is used as the governing equation for water quality transport. Several physically and mathematically based numerical options are provided to solve these governing equations for different application purposes. The surface-subsurface water interactions are considered in the flow module and simulated on the basis of continuity of interface. In the transport simulations, fast/equilibrium reactions are decoupled from slow/kinetic reactions by the decomposition of reaction networks; this enables robust numerical integrations of the governing equation. Kinetic variables are adopted as primary dependent variables rather than biogeochemical species to reduce the number of transport equations and simplify the reaction terms. In each time step, hydrologic/hydraulic variables are solved in the flow module; kinetic variables are then solved in the transport module. This is followed by solving the reactive chemical system node by node to yield concentrations of all species. Application examples are presented to demonstrate the design capability of the model. This model may be of interest to environmental scientists, engineers and decision makers as a comprehensive assessment tool to reliably predict the fluid flow as well as sediment and contaminant transport on watershed scales so as to evaluate the efficacy and impact of alternative watershed management and remediation techniques prior to incurring expense in the field.
Show less - Date Issued
- 2009
- Identifier
- CFE0002947, ucf:47955
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002947
- Title
- IMPACT OF CORROSION INHIBITOR BLENDED ORTHOPHOSPHATE ON WATER QUALITY IN WATER DISTRIBUTION SYSTEMS.
- Creator
-
Alshehri, Abdulrahman, Taylor, James, University of Central Florida
- Abstract / Description
-
The impact of blended orthophosphate (BOP) inhibitor addition on the corrosion of iron, copper, and lead in drinking water distribution systems was studied under changing water quality environment. Release of iron, copper, and lead were monitored at varying inhibitor doses and changing blends of source waters (groundwater, surface water, and desalinated water). Solid corrosion products on pipe surfaces under BOP treatment were evaluated with surface characterization techniques. Performance of...
Show moreThe impact of blended orthophosphate (BOP) inhibitor addition on the corrosion of iron, copper, and lead in drinking water distribution systems was studied under changing water quality environment. Release of iron, copper, and lead were monitored at varying inhibitor doses and changing blends of source waters (groundwater, surface water, and desalinated water). Solid corrosion products on pipe surfaces under BOP treatment were evaluated with surface characterization techniques. Performance of the BOP inhibitor was compared to other corrosion control strategies. Iron scales for iron and galvanized steel coupons incubated in different blended waters in the presence of BOP inhibitor were analyzed by X-ray Photoelectron Spectroscopy (XPS) for surface composition. Identified iron corrosion products were ferric oxide (Fe2O3), magnetite (Fe3O4), and hydrated ferric oxide (FeOOH), in addition to ferric phosphate (FePO4) on coupons exposed to BOP inhibitor. Variations of water quality did not significantly affect the distribution of solid iron forms on surface films. Thermodynamic modeling indicated siderite (FeCO3) was the controlling solid phase of iron release. XPS indicated addition of BOP inhibitor produced a solid phosphate film in the iron scale which could inhibit iron release. Impact of BOP, orthophosphate, and pH adjustment on iron release in a distribution system was examined. Iron release was sensitive to water quality variations (alkalinity and chloride) associated with source and blends of finished water. Finished waters with high alkalinity content (between 149 and 164 mg/L as CaCO3) consistently mitigated iron release regardless of inhibitor use. Dissolved iron constituted about 10% of total iron release. Empirical models were developed that related water quality, inhibitor type and dose to iron release. The BOP inhibitor minimized total iron release followed closely by increasing pH (between 7.9 and 8.1), while orthophosphate dose did not affect iron release. Temperature (ranged from 21.2 to 25.3) had limited influence on iron release with BOP treatment. Monitoring copper release showed that dissolved copper was the dominant form in the effluent, at about 88%. BOP inhibitor doses of 0.5 to 2.0 mg/L proved beneficial in controlling copper concentrations to an average of below 0.5 mg/L. Control of copper release improved with increasing BOP dose, despite changes in alkalinity. Elevation of pH by 0.3 unit beyond pHs (between 7.9 and 8.1) resulted in noticeable decrease in copper concentrations of about 30%, but was more sensitive to higher alkalinity (146 to 151 mg/L as CaCO3) than BOP treatment. Developed empirical models confirmed the importance of BOP inhibitor dose, pH increase, and alkalinity content on copper release. Statistical comparison of the corrosion control strategies proved the advantage of BOP inhibitor, at all doses, over pH elevation in controlling copper release. The BOP inhibitor mitigated lead release below action level, and consistently outperformed pH elevation, in all water quality conditions. XPS analysis identified lead dioxide (PbO2), lead oxide (PbO), cerussite (PbCO3), and hydrocerussite (Pb3(CO3)2(OH)2) as the corrosion products in the scale of lead/tin coupons exposed to BOP inhibitor. XPS and Scanning Electron Microscopy (SEM) analysis suggested cerussite or hydrocerussite is the controlling solid phase of lead release. Thermodynamic models for cerussite and hydrocerussite grossly over predicted actual concentrations. Solubility and equilibrium relationships suggested the possibility of a lead orthophosphate solid that would describe the effectiveness of BOP inhibitor, although no lead-phosphate solid was detected by surface analysis. BOP inhibitor appeared to have mitigated lead release by forming a surface film between lead scale and the bulk water.
Show less - Date Issued
- 2008
- Identifier
- CFE0002229, ucf:47922
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002229
- Title
- A SURROGATE MEASURE OF CUSTOMER SATISFACTION IN THE MANUFACTURE OF PRINTED WIRING BOARDS.
- Creator
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maamoun, Adam, Malone, Linda, University of Central Florida
- Abstract / Description
-
The objective of this research is to determine and develop a model that is capable of accurately measuring customer satisfaction for different industries and in particularly for the Printed Wiring Boards (PWB) Manufacturers. The new model will incorporate data not being collected or utilized by the survey method of determining customer satisfaction. The method used is a weighted average of satisfaction among several researched categories with percentages that accurately represent the relative...
Show moreThe objective of this research is to determine and develop a model that is capable of accurately measuring customer satisfaction for different industries and in particularly for the Printed Wiring Boards (PWB) Manufacturers. The new model will incorporate data not being collected or utilized by the survey method of determining customer satisfaction. The method used is a weighted average of satisfaction among several researched categories with percentages that accurately represent the relative importance of multiple facets of the PWB manufacturers customer satisfaction. A very common term in quality assurance is that "What is not measured accurately can not be evaluated or managed correctly," thus customer satisfaction is a very important aspect of any business, industry, or government. A satisfied customer will do more business and recommend it to other potential customers. Thus the business will grow and more revenues result. On the other hand, an unsatisfied customer will abandon the business and encourage more customers not to get involved with the same business so the business may decline and lose its market share and profitability. The categories that contribute to PWB customer satisfaction will be determined by conducting surveys among the leaders and best in the business of the PWB industry in addition to discovery of related articles that define the categories of the customer satisfaction for the PWB manufacturers. Once the categories are determined, the research concentrates on the weighting of the categories that most contribute to the PWB customer's satisfaction and a measure of satisfaction is derived. The model is easily applied to any other kind of PWB business or service industry. The model is based on empirical methods that will give an accurate measurement for the PWB customer's satisfaction. This in turn allows organizations the opportunity for improving customer satisfaction and increasing market share. The algorithm is based on characteristics deemed important by customers. Thus the customer satisfaction index can be computed and monitored on a regular basis without costly surveys. The major difference between this new model and the standard methods of determining customer satisfaction using the surveys is that this model will utilize data available with the proposals, sales, shipping, receiving, quality, engineering, manufacturing, and purchasing departments. The developed method to measure customer satisfaction utilizing internal data can be more cost effective, more accurate, can provide individual customer satisfaction scores, can measure whether or not these individual scores are statistically lower than the majority, and can provide satisfaction measures in real time none of which can be supplied by the survey method.
Show less - Date Issued
- 2008
- Identifier
- CFE0002219, ucf:47901
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002219
- Title
- DELAY SENSITIVE ROUTING FOR REAL TIME TRAFFIC OVER AD-HOC NETWORKS.
- Creator
-
Darshana, Dipika, Chatterjee, Mainak, University of Central Florida
- Abstract / Description
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Wireless ad hoc network consists of inexpensive nodes that form a mobile communication network. Due to limitations of the transmission range, the nodes rely on each other to forward packets such that messages can be delivered across the network. The selection of the path along which a packet is forwarded from the source node to the destination node is done by the routing algorithm. Most commonly used routing algorithms, though effective for non-real time applications, cannot handle real-time...
Show moreWireless ad hoc network consists of inexpensive nodes that form a mobile communication network. Due to limitations of the transmission range, the nodes rely on each other to forward packets such that messages can be delivered across the network. The selection of the path along which a packet is forwarded from the source node to the destination node is done by the routing algorithm. Most commonly used routing algorithms, though effective for non-real time applications, cannot handle real-time applications that require strict delay bounds on packet delivery. In this thesis, we propose a routing protocol that ensures timely delivery of real time data packets. The idea is to route packets in such a way that irrespective of factors like traffic load and node density, the average delay remains within acceptable bounds. This is done by carefully accessing the resources available to a route before a session is admitted along that route. Each link in the route is checked for sufficient bandwidth not only for the new session to be admitted but also for the sessions that are already using that link. The new session is admitted only if the admission does not violate the delay bounds of any on-going sessions. This method of route selection coupled with per-hop link reservations allows us to provide bounds on the delay performance. Extensive simulation experiments have been conducted that demonstrate the performance of the proposed routing protocol in terms of throughput, session blocking probability, packet drop probability, average path length, and delay.
Show less - Date Issued
- 2008
- Identifier
- CFE0002355, ucf:47796
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002355
- Title
- EFFECTS OF ORTHOPHOSPHATE CORROSION INHIBITOR IN BLENDED WATER QUALITY ENVIRONMENTS.
- Creator
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Stone, Erica, Duranceau, Steven, University of Central Florida
- Abstract / Description
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This study evaluated the effects of orthophosphate (OP) inhibitor addition on iron, copper, and lead corrosion on coupons exposed to different blends of groundwater, surface water, and desalinated seawater. The effectiveness of OP inhibitor addition on iron, copper, and lead release was analyzed by statistical comparison between OP treated and untreated pilot distribution systems (PDS). Four different doses of OP inhibitor, ranging from zero (control) to 2 mg/L as P, were investigated and non...
Show moreThis study evaluated the effects of orthophosphate (OP) inhibitor addition on iron, copper, and lead corrosion on coupons exposed to different blends of groundwater, surface water, and desalinated seawater. The effectiveness of OP inhibitor addition on iron, copper, and lead release was analyzed by statistical comparison between OP treated and untreated pilot distribution systems (PDS). Four different doses of OP inhibitor, ranging from zero (control) to 2 mg/L as P, were investigated and non-linear empirical models were developed to predict iron, copper, and lead release from the water quality and OP doses. Surface characterization evaluations were conducted using X-ray Photoelectron Spectroscopy (XPS) analyses for each iron, galvanized steel, copper, and lead/tin coupon tested. Also, a theoretical thermodynamic model was developed and used to validate the controlling solid phases determined by XPS. A comparison of the effects of phosphate-based corrosion inhibitor addition on iron, copper, and lead release from the PDSs exposed to the different blends was also conducted. Three phosphate-based corrosion inhibitors were employed; blended orthophosphate (BOP), orthophosphate (OP), and zinc orthophosphate (ZOP). Non-linear empirical models were developed to predict iron, copper, and lead release from each PDS treated with different doses of inhibitor ranging from zero (control) to 2 mg/L as P. The predictive models were developed using water quality parameters as well as the inhibitor dose. Using these empirical models, simulation of the water quality of different blends with varying alkalinity and pH were used to compare the inhibitors performance for remaining in compliance for iron, copper and lead release. OP inhibitor addition was found to offer limited improvement of iron release for the OP dosages evaluated for the water blends evaluated compared to pH adjustment alone. Empirical models showed increased total phosphorus, pH, and alkalinity reduced iron release while increased silica, chloride, sulfate, and temperature contributed to iron release. Thermodynamic modeling suggested that FePO4 is the controlling solid that forms on iron and galvanized steel surfaces, regardless of blend, when OP inhibitor is added for corrosion control. While FePO4 does not offer much control of the iron release from the cast iron surfaces, it does offer protection of the galvanized steel surfaces reducing zinc release. OP inhibitor addition was found to reduce copper release for the OP dosages evaluated for the water blends evaluated compared to pH adjustment alone. Empirical models showed increases in total phosphorus, silica, and pH reduced copper release while increased alkalinity and chloride contributed to copper release. Thermodynamic modeling suggested that Cu3(PO4)2•2H2O is the controlling solid that forms on copper surfaces, regardless of blend, when OP inhibitor is added for corrosion control. OP inhibitor addition was found to reduce lead release for the OP dosages evaluated for the water blends evaluated compared to pH adjustment alone. Empirical models showed increased total phosphorus and pH reduced lead release while increased alkalinity, chloride, and temperature contributed to lead release. Thermodynamic modeling suggested that hydroxypyromorphite is the controlling solid that forms on lead surfaces, regardless of blend, when OP inhibitor is added for corrosion control. The comparison of phosphate-based inhibitors found increasing pH to reduce iron, copper, and lead metal release, while increasing alkalinity was shown to reduce iron release but increase copper and lead release. The ZOP inhibitor was not predicted by the empirical models to perform as well as BOP and OP at the low dose of 0.5 mg/L as P for iron control, and the OP inhibitor was not predicted to perform as well as BOP and ZOP at the low dose of 0.5 mg/L as P for lead control. The three inhibitors evaluated performed similarly for copper control. Therefore, BOP inhibitor showed the lowest metal release at the low dose of 0.5 mg/L as P for control of iron, copper, and lead corrosion.
Show less - Date Issued
- 2008
- Identifier
- CFE0002382, ucf:47760
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0002382
- Title
- Kindergarten through twelfth grade student perception of online courses and qualities that lead to course completion.
- Creator
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Peterson, Jennifer, Gunter, Glenda, Swan, Bonnie, Vitale, Thomas, Taylor, Rosemarye, University of Central Florida
- Abstract / Description
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The purpose of this study was two-fold, to understand student perception of the supplemental online courses and improve the online learning program at ABC Online Learning School. The study focused on students in Grades 6 -12 who belonged to the ABC School District and enrolled ABC Online Learning School high school credit courses to supplement their education. Student participants were asked to complete the Student Survey of Online Course Design. The data retrieved from the survey was...
Show moreThe purpose of this study was two-fold, to understand student perception of the supplemental online courses and improve the online learning program at ABC Online Learning School. The study focused on students in Grades 6 -12 who belonged to the ABC School District and enrolled ABC Online Learning School high school credit courses to supplement their education. Student participants were asked to complete the Student Survey of Online Course Design. The data retrieved from the survey was analyzed using the Spearman correlation to establish the strength of the relationship between student perception of quality online course design and the importance of specific components of the online course. The results indicated that as student perception of quality increased, their perception of the importance of the component increased as well. Additionally, a logistic regression formula was used to test the ability to predict successful online course completions based on the developer of the online course (instructor-developed or vendor-developed) and the type of credit the student would earn based on completion (original credit or credit retrieval/recovery). The results of the analysis of the logistic regression showed that developer of the online course and type of credit earned did not have a significant influence on successful course completions. The study is significant because, in Florida, K-12 online courses are funded based on successful course completion and students are required to successful complete an online course to earn a high school diploma.
Show less - Date Issued
- 2018
- Identifier
- CFE0007356, ucf:52099
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007356
- Title
- Assessing the Impact of Radionuclides Released into the Floridan Aquifer by a Massive Sinkhole on Local Municipal Water Supplies.
- Creator
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Arenas Daza, Maria, Duranceau, Steven, Sadmani, A H M Anwar, Wang, Dingbao, University of Central Florida
- Abstract / Description
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In late August 2016, a sinkhole spanning 45 feet (13.7 meters) in diameter opened at a phosphate fertilizer facility (Mosaic Company) near Mulberry, Florida, leaking an estimated 215 million gallons (813,000 cubic meters) of radionuclide-contaminated water 300 feet into the Floridan aquifer. An investigation to determine possible impacts to the environment and local community drinking water supplies was implemented that focused on two 1.5 million gallon per day (MGD) Tampa Bay Water (TBW)...
Show moreIn late August 2016, a sinkhole spanning 45 feet (13.7 meters) in diameter opened at a phosphate fertilizer facility (Mosaic Company) near Mulberry, Florida, leaking an estimated 215 million gallons (813,000 cubic meters) of radionuclide-contaminated water 300 feet into the Floridan aquifer. An investigation to determine possible impacts to the environment and local community drinking water supplies was implemented that focused on two 1.5 million gallon per day (MGD) Tampa Bay Water (TBW) production wells and two Polk County Utilities (PCU) water treatment facilities. Water samples collected between June 2017 and January 2018 at the TBW and PCU sites were found to contain radionuclides below regulated levels. To evaluate the effectiveness of membrane treatment should the TBW and PCU drinking water wells be affected by the spill in the future, bench-scale, flat-sheet reverse osmosis (RO) and nanofiltration (NF) membrane process testing was performed using TBW and PCU wellfield sample aliquots. NF and RO were shown to be capable of removing at minimum of 86 and 92 percent, respectively, of the barium content that had been spiked into groundwater testing aliquots. Based on testing results, a conceptual opinion of probable capital cost for a membrane process ranged from $1.7 and $3.5 million for a 0.25 MGD and 2.0 MGD design capacity, respectively. Process operation and maintenance costs ranged between $0.99/Kgal and $0.26/Kgal for a 0.25 MGD and 2.0 MGD design capacity, respectively. The amortized total cost based on a 20-year period and 8 percent interest rate ranged between $1.88/Kgal for a 0.25 MGD and $0.49/Kgal for a 2.0 MGD design capacity plant. An estimate of unavailable water value due to a long-term well shut-down was approximated as $0.64/Kgal.
Show less - Date Issued
- 2018
- Identifier
- CFE0006970, ucf:52911
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0006970
- Title
- An Engineering Analytics Based Framework for Computational Advertising Systems.
- Creator
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Chen, Mengmeng, Rabelo, Luis, Lee, Gene, Keathley, Heather, Rahal, Ahmad, University of Central Florida
- Abstract / Description
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Engineering analytics is a multifaceted landscape with a diversity of analytics tools which comes from emerging fields such as big data, machine learning, and traditional operations research. Industrial engineering is capable to optimize complex process and systems using engineering analytics elements and the traditional components such as total quality management. This dissertation has proven that industrial engineering using engineering analytics can optimize the emerging area of...
Show moreEngineering analytics is a multifaceted landscape with a diversity of analytics tools which comes from emerging fields such as big data, machine learning, and traditional operations research. Industrial engineering is capable to optimize complex process and systems using engineering analytics elements and the traditional components such as total quality management. This dissertation has proven that industrial engineering using engineering analytics can optimize the emerging area of Computational Advertising. The key was to know the different fields very well and do the right selection. However, people first need to understand and be experts in the flow of the complex application of Computational Advertising and based on the characteristics of each step map the right field of Engineering analytics and traditional Industrial Engineering. Then build the apparatus and apply it to the respective problem in question.This dissertation consists of four research papers addressing the development of a framework to tame the complexity of computational advertising and improve its usage efficiency from an advertiser's viewpoint. This new framework and its respective systems architecture combine the use of support vector machines, Recurrent Neural Networks, Deep Learning Neural Networks, traditional neural networks, Game Theory/Auction Theory with Generative adversarial networks, and Web Engineering to optimize the computational advertising bidding process and achieve a higher rate of return. The system is validated with an actual case study with commercial providers such as Google AdWords and an advertiser's budget of several million dollars.
Show less - Date Issued
- 2018
- Identifier
- CFE0007319, ucf:52118
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007319
- Title
- Predictors of hospital quality and efficiency.
- Creator
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Fotovvat, Hoda, Wan, Thomas, Liu, Albert Xinliang, Ramirez, Bernardo, Yu, Chia-Yuan, University of Central Florida
- Abstract / Description
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American hospitals have made serious efforts to implement and expand their health information technology capabilities and to integrate different specialized care or high-tech services in order to maximize the efficiency and quality of care. In providing a variety of HIT-related services, these hospitals expanded their national reputation in line with integrated care goals. As a result, hospitals are encouraged to establish effective communication channels to facilitate patient-physician...
Show moreAmerican hospitals have made serious efforts to implement and expand their health information technology capabilities and to integrate different specialized care or high-tech services in order to maximize the efficiency and quality of care. In providing a variety of HIT-related services, these hospitals expanded their national reputation in line with integrated care goals. As a result, hospitals are encouraged to establish effective communication channels to facilitate patient-physician sharing of the patient care experience, to enhance effective pain management, and to transform patient-centered care modalities to solidify the adequacy of patient care processes. By analyzing national data sets publicly available, this investigation explored the relationship of acute-care hospitals' performance to the contextual, organizational and patient characteristics, using a cross-sectional study design. This study developed and evaluated the quality and efficiency of hospitals with respects to the structural complexity, process adequacy, efficiency, and quality of care. The structure-process-outcome theory in quality of care developed by Donabedian (1980), is adopted for this investigation. Statistical methods such as confirmatory factor analysis (CFA) and covariance structure model are employed. The population surveyed by the American Hospital Association (AHA) are acute care hospitals throughout the United States, including more than 3000 acute care hospitals of all types of ownership. The data provided by HIMSS Analytics and AHA are available for 2015 and the data provided CMS quality indicators are available for 2016. The key finding of this research is that process adequacy mediates the relationship between hospital structure and performance variables. The efficiency variable played an important role in shaping quality. The location and hospital teaching status have a moderate impact in determining hospital performance by affecting the structure and process of hospitals.
Show less - Date Issued
- 2019
- Identifier
- CFE0007888, ucf:52796
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0007888
- Title
- Academic Engagement through Experiential Learning: Building Transferable Skills within Undergraduate Education.
- Creator
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Lee, Shara, Cintron Delgado, Rosa, Laureano Fuentes, Gloria, Boyd, Karen, Okumus, Fevzi, Dressler, Sheri, University of Central Florida
- Abstract / Description
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Presently, there is a national focus on the industry-benefitting skills developed through undergraduate education. The purpose of this study is to examine the effectiveness of an experiential learning course on building three ability-based transferable skills: communication, emotional intelligence, and professional qualities. These skills have been determined to be important components to the skill set of graduates intending to enter any career, including one within the hospitality industry....
Show morePresently, there is a national focus on the industry-benefitting skills developed through undergraduate education. The purpose of this study is to examine the effectiveness of an experiential learning course on building three ability-based transferable skills: communication, emotional intelligence, and professional qualities. These skills have been determined to be important components to the skill set of graduates intending to enter any career, including one within the hospitality industry. Results from an examination of three related instruments led to conclusions that an experiential learning course positively impacts self-perceived skill development among the three aforementioned skills as well as perception of overall performance. In addition, it was determined that experiential learning courses benefitted interns irrespective of self-reported learning style preference and that such courses may aid in narrowing the perceived gap between intern and employer perceptions of intern skill levels and thereby prepare graduates with increasing success for societal productivity.
Show less - Date Issued
- 2012
- Identifier
- CFE0004568, ucf:49189
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004568
- Title
- THEORETICAL STUDY OF BEAM TRANSFORMATIONS BY VOLUME DIFFRACTION.
- Creator
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Mokhov, Sergiy, Zeldovich, Boris, University of Central Florida
- Abstract / Description
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Laser beams can be manipulated by volume diffractive elements in addition to conventional optical elements like mirrors, lenses, and beam splitters. Conventional optical elements can be described by applying the basic laws of reflection and refraction at the surfaces of the elements. Even diffraction by surface gratings utilizes relatively simple mathematics. This is to be contrasted with the volume diffraction, which requires coupled wave theory in the slowly varying envelope approximation ...
Show moreLaser beams can be manipulated by volume diffractive elements in addition to conventional optical elements like mirrors, lenses, and beam splitters. Conventional optical elements can be described by applying the basic laws of reflection and refraction at the surfaces of the elements. Even diffraction by surface gratings utilizes relatively simple mathematics. This is to be contrasted with the volume diffraction, which requires coupled wave theory in the slowly varying envelope approximation (SVEA) to obtain accurate results. Efficient spatially distributed diffraction of laser beams is possible due to the high coherence of laser light, and it occurs at specific resonant Bragg conditions. This research work is inspired and driven by the successful development of recording technology for robust, high-efficiency volume Bragg gratings (VBGs) in photo-thermo-refractive (PTR) glass. Mostly VBGs of the reflective type are discussed in this dissertation. Starting with an analysis of electro-magnetic wave propagation in layered media, we have reformulated Fresnel and volume reflection phenomena in terms of a convenient parameter S - strength of reflection. The influence that the different non-uniformities inside a VBG have on its spectral properties has been examined. One important result of this work is the proposal of moire VBG and the derivation of an analytical expression for its bandwidth. A multiplexed VBG used as a coherent combiner is discussed as well. Beam distortion via transmission through and/or reflection by a heated VBG due to residual absorption is analyzed.
Show less - Date Issued
- 2011
- Identifier
- CFE0004054, ucf:49152
- Format
- Document (PDF)
- PURL
- http://purl.flvc.org/ucf/fd/CFE0004054
