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Title: A Monte Carlo evaluation of ridge regression as an alternative to ordinary least squares
Creator: Coyle, Bryan Walter
Date: 1979
Collection: Electronic Theses & Dissertations

Title: A Monte Carlo study of different detector geometries for HAWC
Creator: Gebauer, Iris
Date: 2005
Collection: Electronic Theses & Dissertations

Title: A NARR derived low-level jet climatology over North America
Creator: Doubler, Dana L.
Date: 2013
Collection: Electronic Theses & Dissertations
Description: Previous climatological studies of low-level jets (LLJs) have been restricted to individual geographic regions. In this study, an expanded climatology of the characteristics of northerly low-level jets (N-LLJs) and southerly low-level jets (S-LLJs) is provided for North America and nearby coastal areas to better document the spatial variations of these important mesoscale circulation features. In addition, time of initiation and persistence of S-LLJ events in central North America and over...
Show morePrevious climatological studies of low-level jets (LLJs) have been restricted to individual geographic regions. In this study, an expanded climatology of the characteristics of northerly low-level jets (N-LLJs) and southerly low-level jets (S-LLJs) is provided for North America and nearby coastal areas to better document the spatial variations of these important mesoscale circulation features. In addition, time of initiation and persistence of S-LLJ events in central North America and over the Gulf of Mexico are analyzed. The North American Regional Reanalysis (NARR), with a 32-km horizontal resolution and a 3-hourly temporal resolution, was used to analyze (by time of day, month, season and year) the frequency, height above ground level, and wind speed of LLJs, and, for S-LLJs in central North America only, diurnal and seasonal variations in the time of initiation and duration jet events. The spatial analyses highlight well-known wind maxima but also point to previously-unknown locations that experience frequent jet-like wind maxima. The analyses also suggest that boundary-layer forcing is important for S-LLJ occurrence, including S-LLJs that form at high latitudes in summer and those that form in the central and southern plains in winter. The NARR-derived analyses supplement and enhance the understanding of the climatological characteristics of low-level wind maxima across North America and coastal environs. The findings also highlight that many aspects of low-level wind maxima remain incompletely understood and point to the need for considerable further research on the processes contributing to jet formation.
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Title: A NUMERICAL AND EXPERIMENTAL INVESTIGATION OF A SUBSURFACE STEP USING FLASH THERMOGRAPHY
Creator: Nejdl, David
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Flash thermography (FT) is a well-established non-destructive testing (NDT) technique that uses a short (~msec) pulse from a flashlamp to uniformly heat the surface of a sample and interrogate its subsurface structure based on the surface temperature response, measured with an infrared (IR) camera. Heat flow into a defect-free sample is described by a 1-D diffusion model, which transitions to higher dimensions due to subsurface discontinuities. 1-D approaches can be unreliable in the vicinity...
Show moreFlash thermography (FT) is a well-established non-destructive testing (NDT) technique that uses a short (~msec) pulse from a flashlamp to uniformly heat the surface of a sample and interrogate its subsurface structure based on the surface temperature response, measured with an infrared (IR) camera. Heat flow into a defect-free sample is described by a 1-D diffusion model, which transitions to higher dimensions due to subsurface discontinuities. 1-D approaches can be unreliable in the vicinity of abrupt thickness change, termed as the ‘transition zone,’ where lateral heat flow from the thin to thick region may mask surface temperature changes due to heat flowing into the part. In this work, we quantify the uncertainty in a “subsurface step,” of a steel sample heated on its front flat and smooth surface, while the thickness (L) of the plate changes with a known step size (dL) on the backside. Finite element models simulating the FT process were developed to understand the effect of sub-surface steps on the thermal diffusion and compared with experiments for 12 varying step (dL/L) combinations. The width of the transition zone was measured using the Thermographic Signal Reconstruction (TSR) method. Results indicate that the transition zone can be defined simply as a function of its geometry. Experiments confirmed that the model predictions work well under the assumption that the steps are properly distinguishable from each other. Lastly, equations to estimate the detectability of a step were developed to be used in addition to the camera’s detection limits. Overall, the approach used can be extended to anisotropic materials such as composites and bonded joints to enable efficient NDT of structural components.
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Title: A Novel, Algal-based Chemical Absorption System for Post-combustion Carbon Dioxide Capture
Creator: Smerigan, Adam John
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Post-combustion carbon dioxide capture using amine solutions is an integral technology for reducing carbon dioxide emissions from the energy sector. However, environmental impacts and economic costs are restricting the implementation of amine absorbents. This study investigated the development of a sustainable algal based chemical absorption process to capture post-combustion carbon dioxide efficiently. Microalgal biomass was hydrolyzed to amino acids under basic conditions at 134oC. The...
Show morePost-combustion carbon dioxide capture using amine solutions is an integral technology for reducing carbon dioxide emissions from the energy sector. However, environmental impacts and economic costs are restricting the implementation of amine absorbents. This study investigated the development of a sustainable algal based chemical absorption process to capture post-combustion carbon dioxide efficiently. Microalgal biomass was hydrolyzed to amino acids under basic conditions at 134oC. The supernatant of the hydrolysate was purged with carbon dioxide following centrifugation, and then underwent a desorption process to regenerate a chemical absorption algae-based solvent. A mass balance of the process showed that 31% of the mass into the process was recovered as an algal amino acid product. Another 30% exited the process as wet potassium carbonate which could be recovered as potassium hydroxide. The algal amino acid absorbent product contained 0.592 mol amino acid/L composed primarily of alanine, glutamic acid, glycine, aspartic acid, leucine, lysine, and proline. A trickling filter absorption column was built to determine the absorption capacity of the algal amino acid solution. The algal absorbent (0.731 ± 0.037 mol CO2/mol amine) had a higher absorption capacity than a synthetic amino acid absorbent (0.512 ± 0.014mol CO2/mol amine) composed of glycine, alanine, proline, and lysine. Both solutions were highly regenerable showing no signs (p<0.05) of deterioration after multiple absorption and desorption cycles based on the pH of the solution, absorption capacity, and ATR-FTIR spectra. Using algal biomass as a cheap and sustainable source of amino acids is a viable alternative to synthetic amino acid absorbents.
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Title: A PERMIAN ACTINOPTERYGIAN FROM THE MINNEKAHTA LIMESTONE OF SOUTH DAKOTA, USA
Creator: Stack, Jack Reza
Date: 2021
Collection: Electronic Theses & Dissertations
Description: The interrelationships and phylogenetics of extinct Paleozoic and Early Mesozoic ray-finned fishes (Actinopterygii) are obscured by a low-quality fossil record and understudy of Late Paleozoic (Permo-Carboniferous) actinopterygians. To help address this issue, I describe a new species of ray-finned fish from the late Early Permian Minnekahta Limestone of South Dakota. This taxon is represented by two specimens, Field Museum of Natural History PF 3721 and Yale Peabody Museum 18649. PF 3721 is...
Show moreThe interrelationships and phylogenetics of extinct Paleozoic and Early Mesozoic ray-finned fishes (Actinopterygii) are obscured by a low-quality fossil record and understudy of Late Paleozoic (Permo-Carboniferous) actinopterygians. To help address this issue, I describe a new species of ray-finned fish from the late Early Permian Minnekahta Limestone of South Dakota. This taxon is represented by two specimens, Field Museum of Natural History PF 3721 and Yale Peabody Museum 18649. PF 3721 is an exceptionally well-preserved partial three-dimensional head and trunk preserving the external anatomy of and some internal elements from the skull, paired fins, and scale cover. YPM 18649 is a partially articulated, laterally compressed individual with a heavily disarticulated skull. This fish has features of the paraphyletic "paleoniscoid" group, including an immobile maxilla with a narrow suborbital process and a broad postorbital expansion, a heterocercal caudal fin, and rhombic ganoid scales. I conducted an equally weighted maximum parsimony analysis in PAUP and a Bayesian analysis with the Mkv model of morphological evolution in MrBayes with 73 other taxa and 222 characters that placed this taxon in a polytomy with other Late Paleozoic and Early Mesozoic "paleoniscoids" in the respective consensus trees. I recommend the application of parsimony and Bayesian inference techniques in tandem to the problem of early actinopterygian interrelationships to provide necessary caution and direction to future work.
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Title: A PILOT STUDY OF WEB-BASED INFORMATION BOTTLENECK IDENTIFICATION IN AEC PROJECTS
Creator: Pandey, Nishchhal Nihal
Date: 2022
Collection: Electronic Theses & Dissertations
Description: The success of the Architecture, Engineering, and Construction (AEC) project relies heavily on the effective communication and information exchange between project team members. A prominent reason for delays and progress shortcomings in AEC project teams is information bottlenecks, defined as missing project information bits which can be due to large influx of information or inadvertent withholding of information at a particular time. Information bottlenecks both in planning and execution...
Show moreThe success of the Architecture, Engineering, and Construction (AEC) project relies heavily on the effective communication and information exchange between project team members. A prominent reason for delays and progress shortcomings in AEC project teams is information bottlenecks, defined as missing project information bits which can be due to large influx of information or inadvertent withholding of information at a particular time. Information bottlenecks both in planning and execution phases of the project tend to cause schedule delays and cost overruns. Information and communication exchange patterns between project team members shed a light on the possible occurrence of information bottlenecks. Recent literature efforts have focused on use of software programming and key performance indicators (KPIs) to identify which phases of project are prone to occurrence of bottlenecks. One of the roadblocks in implementing majority of bottleneck identification techniques in AEC projects is the difficulty in execution. Some of the metrics defined are too complex and require rigorous manual calculations. Given the complexity and feasibility difficulties of the present methodologies for identification of bottleneck, this study aims to contribute to the body of knowledge by providing an adaptable tool that aims to improve the accuracy and practicality for predicting bottlenecks. Therefore, the research question this research aims to answer is “Can the usability and adaptability of information bottleneck prediction in AEC projects be improved through a web-based tool?”Expanding on Lean Construction concepts, key performance indicators (KPIs), efficiency, quantification metrics are developed to study the trends of information shared between AEC project team members. The developed model is semi-automated and reads data by importing the Microsoft Excel sheet which has all the raw project documentation data. A Python code developed by the researcher is used to extract information from the excel, create a dashboard, and publish information bottleneck calculations through a web-based tool. Statistical inferences drawn from the model are then be used to identify occurrence of project bottlenecks. The web-based platform is designed to cater the specific information exchange trends in a typical project. Providing visual representations, and explanations further ease the understanding of the root issue. Finally, through two expert interviews, the web tool is revised, and final tool is presented, and future directions of work are discussed.
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Title: A Q-study in role identification using a sample of advertising photographs
Creator: Koch-Weser, Elke
Date: 1961
Collection: Electronic Theses & Dissertations

Title: A Q-study of the image of public education and one local school district
Creator: Winegar, Lois Hicks
Date: 1973
Collection: Electronic Theses & Dissertations

Title: A SECONDARY ANALYSIS OF SBHC-REPORTED MENTAL HEALTH SERVICES, STRUCTURAL CHARACTERISTICS, AND STATE LEVEL SUPPORT FROM 2005-2014
Creator: Bustos, Tatiana Elisa
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Background: More than 20% of children and youth in the U.S. experience mental health difficulties, with only about 30% receiving adequate mental health treatment services. School based health centers (SBHCs)—a comprehensive service delivery model integrating physical and mental health services within school settings—reduce barriers to health services faced by low-income families and children. Given the potential of SBHCs to improve the lives of children with mental healthcare needs, it is...
Show moreBackground: More than 20% of children and youth in the U.S. experience mental health difficulties, with only about 30% receiving adequate mental health treatment services. School based health centers (SBHCs)—a comprehensive service delivery model integrating physical and mental health services within school settings—reduce barriers to health services faced by low-income families and children. Given the potential of SBHCs to improve the lives of children with mental healthcare needs, it is necessary to explore the delivery of mental health (MH) services among SBHCs longitudinally, and identify key structural characteristics, networks, and state level supports that promote delivery of MH services across U.S. states. Method: Guided by the contextualist approach, secondary analyses of two longitudinal datasets (National SBHC Census & State Policy Survey) were carried out to: (1) identify the number of MH services reported to be delivered by state over time, and (2) identify inner and outer contexts of SBHCs with a MH component related to number of services. The consolidated framework for implementation (CFIR) was used to organize variables and guide interpretation of findings related to the interplay of contexts and delivery of services. Findings: Results suggest that specific inner and outer setting variables are related to more MH services from 2005 to 2014, but the variables had differential impacts on which type of MH service was delivered. Moreover, mandatory policies for state-funded SBHCs demonstrated more MH services over time than those otherwise. Discussion: Understanding the factors facilitating delivery of MH services is necessary to better inform policy efforts that can increase service access among underserved youth.
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Title: A TAT research measure for assessing adult correlates of early childhood separation-individuation dynamics
Creator: Berry, Deborah Kay
Date: 1985
Collection: Electronic Theses & Dissertations

Title: A VLSI chip architecture for the B-spline surface evaluation
Creator: Maa, Chia-Yiu
Date: 1987
Collection: Electronic Theses & Dissertations

Title: A Venezuelan model of codetermination
Creator: Jimenez, Ricardo
Date: 1983
Collection: Electronic Theses & Dissertations

Title: A WWV synchronized digital clock
Creator: Cooper, David Alan
Date: 1979
Collection: Electronic Theses & Dissertations

Title: A bacteriological and biochemical study of different methods of salting onions
Creator: Jones, Arthur David
Date: 1945
Collection: Electronic Theses & Dissertations

Title: A bacteriological study of cottage cheese with particular reference to public health hazard
Creator: Lyons, Paul Robert
Date: 1953
Collection: Electronic Theses & Dissertations

Title: A bacteriological study of drinking fountains
Creator: Fontes, Antone King
Date: 1954
Collection: Electronic Theses & Dissertations

Title: A baseline analysis of poaching in Chiquibul National Park
Creator: Groff, Katherine
Date: 2011
Collection: Electronic Theses & Dissertations
Description: Illegal hunting of wildlife, also known as poaching, in Chiquibul National Park (CNP) may be contributing to decreasing wildlife populations. Management strategies are limited due to a lack of information on the extent of poaching and motivations of poachers. The objectives of this research are to assess the extent of poaching, to address Guatemalan border community residents' understanding of wildlife in CNP and what animal species are targeted by hunters, and to investigate factors...
Show moreIllegal hunting of wildlife, also known as poaching, in Chiquibul National Park (CNP) may be contributing to decreasing wildlife populations. Management strategies are limited due to a lack of information on the extent of poaching and motivations of poachers. The objectives of this research are to assess the extent of poaching, to address Guatemalan border community residents' understanding of wildlife in CNP and what animal species are targeted by hunters, and to investigate factors affecting poaching in CNP and Guatemalan border residents' perceptions about poaching in CNP. These objectives were addressed by (1) synthesizing information found in CNP Ranger field notebooks and reports, (2) interviewing Guatemalan border community residents, and (3) interviewing authorities in Guatemala and Belize. Guatemalan border community residents perceived a lower level of poaching in the CNP than CNP rangers, but both thought that poaching has decreased over the years. CNP rangers considered poaching to be a danger to wildlife in the area, and they thought that wildlife numbers have suffered due to poaching. This research demonstrated little support for the hypothesis that legal regulations and the enforcement of regulations are factors that contribute to whether respondents view other community members as contributing to poaching. However, the subsistence needs of hunters and their families is an important factor affecting residents' decision to poach. When subsistence was included in a logistic multivariate regression with legal regulations, regulations lost significance and subsistence was highly significant. Subsistence needs appear to be worth the risk of being caught poaching by authorities.
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