MavMatrix (University of Texas at Arlington)
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The Impact of Maternal Age on the Expression of Transgenerational Plasticity in Daphnia pulicaria
Get PDFTransgenerational plasticity refers to heritable, non-genetic changes in phenotype that persist across multiple generations and can enhance offspring survivability in variable environments. In Daphnia, increasing maternal age has been associated with maladaptive plasticity. To investigate this relationship, six clones were collected from two Wisconsin lakes and acclimated to laboratory conditions through a common garden rearing process. For each clone, ten replicates were generated and evenly divided between young (clutches 2–4) and old (clutches 5–8) maternal age groups. Offspring were exposed to three dietary treatments for three experimental generations: one fed only green algae, one fed only cyanobacteria (a nutritionally limiting food source), and a third fed cyanobacteria in the first generation, followed by green algae in subsequent generations. Body size, absolute eye size, and relative eye size were measured as proxies for fitness and plasticity and analyzed using linear mixed models. As expected, offspring of younger mothers initially exhibited greater fitness. However, in both the mixed treatment and continual cyanobacterial treatment, offspring of older mothers outperformed those of younger mothers, suggesting a potential compensatory transgenerational response from older Daphnia mothers to initial environmental stress
Individual Brainstorming: Exploring the Efficacy of the Cyclical Divergent to Convergent Innovation Model (CDCIM)
Get PDFThis thesis explored the adaptation of the Cyclical Divergent to Convergent Innovation Model (CDCIM), a structural model used in group brainstorming settings, to the context of individual brainstorming. The primary objective was to investigate whether this brainstorming model enhances the creative output of individuals in terms of idea quantity, quality (based on novelty and feasibility), and divergence in the final output. The study employed an experimental design involving 174 participants, divided into two conditions: Linear (C1), and CDCIM (C2). Participants were tasked with designing various aspects of a futuristic university. The results showed that participants in the CDCIM condition generated significantly more ideas. However, no significant difference was found in terms of novelty, feasibility, final plan quality, and divergence in the final output. These mixed findings provided insights into the mechanisms of individual creativity, suggesting that while structured cycles may support idea fluency, they may not be enough to enhance creative output without additional sources of stimulation or cue diversity. Additionally, the study discussed additional insights and acknowledged challenges and limitations of using the CDCIM model to individual contexts, aiding future research in this area
DEEP NEURAL NETWORK MODELS FOR HEATSINK PERFORMANCE PREDICTION AND OPTIMIZATION IN SINGLE PHASE IMMERSION COOLING: Framework for Future Design Tools and Digital Twin Integration
Get PDFThe rapidly rising computational power of modern computing components combined with the advanced packaging techniques being implemented has resulted in exponentially increasing thermal design powers (TDP) from CPUs and GPUs. Traditional air-cooling methods are approaching their effective cooling limits for many of these components, requiring lower supply air temperatures, higher supply air flowrates, and much larger heatsinks to remain feasible. Transitioning from air-cooling to single-phase immersion cooling offers numerous benefits in thermal performance, data-center size reduction, and energy efficiency. To leverage the merits of immersion cooling, the performance of a given heatsink must be predicted and optimized for best performance for a given condition. This study presents the use of deep learning (DL) and deep neural networks (DNN) to construct a design tool that can predict the performance characteristics of heatsinks in single-phase immersion cooling. Utilizing a validated synthetic dataset of 15,552 data points generated by parametric CFD simulation, multiple DNN models are trained to predict the thermal-hydraulic performance of a heatsink based on the choice of immersion fluid, flowrate, temperature, component power, and heatsink geometry. When deployed for inferencing, the DNN models show that they are generally capable of making accurate predictions (5.11% MPE) when exposed to input parameter combinations outside of the training or validation datasets. The developed DNN models are additionally applied in a modular neural network architecture, which is an architecture where multiple independent, smaller DNNs are connected together to model an overall larger, more complex system. This investigation shows that the DNN models developed can be successfully expanded to this application and still yield mostly accurate predictions (~7.65% MPE) even though this application is beyond the training range. The developed DNN models are also implemented into a multi-objective, multi-variable optimization framework demonstrating their ability to be used for rapid optimization studies. When deployed in this application, the DNNs were able to complete a 10,000 point optimization in 2.071 seconds with only a 3.9% MPE compared to CFD. The development of this design tool results in a system that can be utilized to replace or augment traditional CFD studies, reducing lead time and cost in development of effective heatsinks for a given single-phase immersion cooling application. The methodology developed additionally serves as a starting framework for further expansion into the development of rapid design tools and digital twins for data centers
Comparative Life Cycle Assessment of Conventional Open-Cut Pipeline Replacement with Trenchless Cured-in-Place Pipe Renewal Method for Wastewater Applications Using Midpoint Approach
Get PDFUnderground infrastructure development has a significant impact on society, leading to continuous technological advancements. With the rising environmental concerns, novel technology is leaning towards adapting to sustainable practices for pipeline rehabilitation. Conducting a comparative study of environmental impacts produced by pipe renewal and replacement processes is a vital step towards sustainable development of underground infrastructure. Open-cut Pipeline Replacement (OCPR) is the conventional method used for pipeline rehabilitation, which involves the excavation of the ground surface to place a new pipe underground or replace an existing one. This process includes the trenching of ground, followed by surface reinstatement through backfill. The procedure requires removal of debris to enable smooth removal and replacement of the sewer pipe, thereby requiring more resources and increasing its overall environmental impact. Cured-in-Place Pipe (CIPP) renewal is a popular trenchless technology, involving the insertion of a liquid thermoset resin-saturated material into an existing pipe through air or water inversion, or by mechanically pulling-in and inflating the tube. Using hot water, steam or ultraviolet (UV) light, the liner material is cured inside the host pipe, leading to the production of CIPP product. The primary objective of this thesis research is to compare the environmental impacts from conventional open-cut pipeline replacement (OCPR) and trenchless cured-in-place pipe (CIPP) renewal method for small diameter sanitary sewers using midpoint approach. Further, this study aims to (1) conduct a comprehensive literature review from 1990 through 2025 (35 years), about environmental impacts from OCPR and CIPP methods, (2) categorize, systematize and visualize the literature review data using VOSViewer software and Microsoft Excel-OpenAlex combination, and (3) identify the factors influencing environmental impacts caused by both alternatives. Four case studies on sewer rehabilitation projects from around the US were selected to quantify the environmental impacts of OCPR and CIPP renewal for small diameter sewer pipes ranging between 8-12 inches. The comparative life cycle assessment (LCA) was performed using two midpoint impact assessment methods of SimaPro software, namely TRACI 2.2 and ReCiPe 2016 Midpoint (H). The results show that CIPP renewal reduces environmental impact by 56%, with global warming reduced by 71%, fossil fuel depletion by 72%, acidification by 54%, smog formation by 67%, and respiratory effects by 52%. A similar approach can be used to perform LCA of other pipe sizes, varying project and environmental conditions, different resins, curing methods, and liner thicknesses for CIPP, soil types, and pipe materials. This research develops an LCA framework to quantify and compare environmental impacts from OCPR and CIPP. Project and utility owners, cities, municipalities, decision makers, and contractors commonly take into consideration only the construction costs and sometimes overlook the LCA aspects while making a choice between open-cut and trenchless pipeline installation. Therefore, this study will be helpful for project owners and contractors to facilitate their decision-making process to select a more sustainable pipe rehabilitation method
American Airlines Stewardess College Graduation
No full textSandra Dietrich, class favorite of the Class of 60-2 of American Airlines Stewardess College. Fort Worth Star-Telegram Morning February 18, 1960.https://mavmatrix.uta.edu/specialcollections_startelegram1960s/5567/thumbnail.jp
Miss Helen Keith and I. E. Mcwhirter
No full textMiss Helen Keith, member of the 1959 Star-Telegram Ranch and Farm Tour of Europe, visits with I. E. Mcwhirter, tour director. Fort Worth Star-Telegram Morning April 15, 1960.https://mavmatrix.uta.edu/specialcollections_startelegram1960s/5570/thumbnail.jp
Captain Joe N. Weems, Hunter Barrett and Brigadier General Nils O. Ohman
No full textDiscussing the Titan missile in the background are (left to right) Captain Joe N. Weems, Hunter Barrett and Brigadier General Nils O. Ohman. Fort Worth Star-Telegram Evening March 3, 1961.https://mavmatrix.uta.edu/specialcollections_startelegram1960s/5583/thumbnail.jp
American Airlines Stewardess College Graduation
No full textGraduation day for the 48 girls is Class 61-5 at the American Airlines Stewardess College at Carter Field. The girls began graduation ceremonies by marching to the stairway overlooking the lobby for a few songs to the accompaniment of piano music provided by their classmate, Carol Fabian. Fort Worth Star-Telegram Morning July 2, 1961.https://mavmatrix.uta.edu/specialcollections_startelegram1960s/5591/thumbnail.jp
Texas Christian University Travel Club
No full textMayor Pro-Tem Frank Keeton is caught in the middle as he is given the traditional Hawaiian aloha by (left) Rose Marie Alvaro and Leolani Blaisdell at the Star-Telegram-Texas Christian University (TCU) Travel Club program. Fort Worth Star-Telegram Morning November 9, 1961.https://mavmatrix.uta.edu/specialcollections_startelegram1960s/5599/thumbnail.jp