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End-to-End (E2E) Model-Based Systems Engineering (MBSE) Framework
Full text linkThis presentation explores the latest advancements in systems engineering, with a particular focus on Model-Based Systems Engineering (MBSE). It covers key definitions, benefits, applications, and challenges associated with these methodologies, as well as analyzes current frameworks and research methodologies in the field
Thermophysical Properties of Aqueous Amine Salts for closed Air Cabin Revitalization
Full text linkCarbon dioxide (CO2) capture plays a crucial role in closed cabin air revitalization, however current CO2 capture technologies pose several issues. Traditional amine solutions, such as monoethanolamine, are commonly used in CO2 capture on the International Space Station but face drawbacks including high volatility, thermal degradation, and unpleasant odor. To overcome these challenges, amine salt solutions have emerged as promising alternatives. Amine salt solutions have reduced environmental impact, lower corrosion potential, and improved CO2 loading capacity, making them a more efficient and sustainable replacement. Knowing these physical properties are critical for modeling and optimizing a scrubbing process that employs these new solvents. This research investigates the feasibility of using amine salt solutions for CO2 capture by measuring their thermophysical properties—viscosity, surface tension, density, and heat capacity—under different CO2 loading temperatures, with varying salt mixture concentrations. The viscosity, surface tension, density, and heat capacity of amine salt solutions were measured using a rheometer, goniometer, densitometer, and differential scanning calorimeter, respectively. Preliminary findings indicate that CO2 loading slightly increases the amine salts’ viscosity and alters surface tension, which can affect mass transfer reaction CO2 uptake in scrubbing processes. Density and heat capacity measurements provide understanding of the salts’ thermal properties and process efficiency. Current research includes completion of measurements of amine salt mixtures, VFT property modeling, and ApsenPlus+ integration.https://jagworks.southalabama.edu/southalabama-shgrf-posters/1021/thumbnail.jp
Flexible Bit-Truncation Memory for Low-Power Quality-Adaptive Video and Deep Learning Storage
No full textTo effectively function, Artificial intelligence-based applications, computation-intensive data processing, and image processing demand effective memory design. This work introduces truncation capable memory design running in 16-bit or 32-bit systems to facilitate specific bit reduction to improve the power efficiency. We have used power gating to turn the power off for targeted bits for specific applications. We present a novel bit-truncation memory with full truncation flexibility, which can truncate any number of data bits at run time to meet different quality and power savings trade-off requirements for different applications. This design can automatically set the truncated bits to the optimal values for both videos and DNN, thereby optimizing the quality to realize maximum power savings. Proposed hardware is suitable for deep learning inference and image/video processing workloads because its runtime truncation capability maximizes the efficiency vs. quality trade-off. This proposed hardware architecture is also compatible for quantization methods like float16 quantization as it reduces the model size without much changing the computational performance. AI workloads can also be optimized by incorporating truncation and model pruning techniques that eliminate the neural network redundancies without affecting accuracy levels. A number of truncation modes in this memory can offer improved performance on a range of hardware platforms like embedded systems and AI accelerators. As a future work, we can test this hardware and its performance on actual silicon chips to see how practically this chip functions with state-of-the-art quantization and pruning techniques.https://jagworks.southalabama.edu/southalabama-shgrf-posters/1033/thumbnail.jp
Effects of the Gravity Gradient on the Path of 1I/‘Oumuamua
Full text linkIn October 2017, the asteroid 1I/’Oumuamua first passed into viewing range [1]. The asteroid is notable for being the first interstellar object to enter the solar system. 1I/’Oumuamua was also unusual in its geometry; it is thought to have an aspect ratio of 6:1 and a length of approximately 400 m [2] [3]. The asteroid was observed to experience a non-Keplerian acceleration estimated to be on the order of 1⇥10−6 m s2 . Several theories have been proposed for the cause of this acceleration, all of which are non-gravitational in nature: volatile outgassing, photon pressure, and solar winds [1][4]. However, none of these sources have been definitively proven to be able to provide accelerations large enough to explain the unexpected motion [1] [5]. This project aims to examine the possibility of gravitational efforts on the orbital mechanics of 1I/’Oumuamua due to its elongated shape. For elongated objects, the center of mass and center of gravity are not generally at the same point on the body [6]. This offset between the center of mass and center of gravity causes a torque about the center of mass which is absent in objects able to be approximated as a particle. This project aims to determine whether the additional torque enables the development of an additional acceleration sufficient to explain the unexpected non-Keplerian acceleration observed in 1I/’Oumuamua. Lagrange’s equations were used to develop equations of motion for 1I/’Oumuamua, and these equations were solved through the use of an RK4 algorithm and compared to the Keplerian analytical solution for a particle. Ultimately, it was determined that the additional acceleration experienced by 1I/’Oumuamua of length 400 m at a perihelion distance of 38,100,000 km was potentially on the order of magnitude of 2.5195 ⇥ 10−18 m s2 , a value far too small to explain the additional acceleration observed for 1I/’Oumuamua. Additionally, an asteroid of 400 m experienced a maximum offset from the Keplerian orbital radius of approximately 394 m, an insignificant amount for any asteroid risk assessment efforts. However, pronounced effects were observed for asteroids of 1,000 km or greater, indicating that the additional torque does affect the orbital behavior of elongated asteroids. Additional efforts to quantify this effect for other orbital scenarios and initial conditions will further clarify the additional accelerations and altered orbital paths experienced by elongated asteroids and enable this analysis to be implemented into asteroid risk assessment efforts
Comparing Online and In-Person Social Support and its Effects on Suicidal Ideation
Full text linkAccording to the interpersonal theory of suicide, thwarted belonging and perceived burdensomeness are proximal causes of suicidal ideation (Van Orden et al., 2010). Studies show that a lack of social support can lead to higher levels of thwarted belonging and perceived burdensomeness (Sparks et al., 2023). This relationship between social support and suicidal ideation has been studied in the literature, but the relationship between online and in-person social support with suicidal ideation has not. The purpose of the current study is to examine the effects of in-person and online social support on different factors of the interpersonal theory of suicide. We examined the indirect effects of thwarted belonging and perceived burdensomeness on the relationship between social support and suicidal ideation, as well as the bivariate correlations among these variables. The study sample consisted of 313 undergraduate college students who completed online questionnaires. The participants had a mean age of 19.53 (SD = 2.75), with the majority being female (71.9%), and were 70.4% Caucasian, 14.4% African American, 5.8% Asian, and 3.8% Hispanic. Results show that online and in-person social support are significantly correlated with lower levels of suicidal ideation, but this relationship is stronger with in-person social support. The indirect effects are only significant for in-person family support and ideation through perceived burdensomeness. The online support model had no significant effects. These results suggest that there is a difference between in-person and online social support and their effect on suicidal ideation
Decoding Bacterial Resilience: sRNAs and Sigma Factors in Stress Adaptation and Persistence of Salmonella
Full text linkSmall RNAs (sRNAs) are noncoding RNA molecules in bacteria that function primarily to regulate gene expression, including those associated with stress. The Borchert Lab has identified 173 sRNAs and \u3e 500 sRNAs that are responsive to desiccation and carbon starvation (c-starvation), respectively. Prokaryotic transcription involves an RNA Polymerase (RNAP) that transcribes DNA into RNA. RNAP involves sigma factors, which recognize promoters for the initial steps of RNA synthesis. The Borchert Lab has determined that there are significant overlaps between sRNAs expressed in cells subjected to both short-term durations and long-term durations of carbon starvation. Salmonella enterica serovars can have outbreaks associated with dehydrated foods. Understanding the mechanism that allows for S. enterica survival under stress allows for building strategies in combating the spread of this pathogen and preventing recurrent Salmonella outbreaks. We hypothesize that in S. enterica serovars, the bacteria express sigma factor RpoS during short term stress while switching over to sigma factor RpoE during long term stress. This switch between the sigma factors function to regulate the stress response in S. enterica. RNAP sigma subunit selection and the expression of distinct sRNAs drive the decision between active stress resistance and formation of persisters. Our findings suggest that sigma factor expression of RpoS in the Salmonella strain SL1344 is dependent on the duration of stress
Binary Solid/Liquid Equilibrium of Mixtures of Thermally Robust Salts and Molecular Compounds for use as Heat Transfer Fluids
Full text linkFossil fuels, contributors to climate change that may bear catastrophic consequences, power the entire world. The human species is almost entirely dependent on fossil fuels for energy, but other sources of renewable and environmentally friendly energy must be developed. Concentrated solar power (CSP) is a promising source of renewable energy with hampered potential—better heat transfer fluids (HTFs) are needed for it to be economically feasible. Currently, the HTFs in industrial use are predominantly either synthetic oils or nitrate-based molten salts. Synthetic oils are only stable up to 400 °C, and molten salts often have high melting temperatures, making them prone to freezing. Therefore, ionic liquids are being investigated as an alternative heat transfer fluid. Ionic liquids often have high thermal stability, high heat capacity, and low melting points. An ionic liquid like tetraphenylphosphonium bistriflimide (TPP), combined with aromatic compounds, such as diphenyl ether, shows potential as an HTF. In this report, digital scanning calorimetry (DSC) data of binary mixtures of TPP and diphenyl ether was analyzed using binary a binary T-x plot, which was compared to an ideal eutectic model, and Tammann’s triangle, which provided a more accurate prediction of the eutectic composition, in order to make a comprehensive graph of the solid-liquid equilibrium (SLE) behavior. This data provided valuable insights into the thermodynamic properties of this mixture, including evidence about the eutectic composition and melting temperature. The eutectic composition is of special interest for its unique thermodynamic properties, including a very low melting temperature, which offers potential for use in CSP technology, significantly reducing the risk of catastrophic HTF freezing that leads to plant shutdowns and unreliability.https://jagworks.southalabama.edu/honors_college_posters/1041/thumbnail.jp
Joan Browning Presentation Photo 3
No full textMs. Browning speaking during her presentation at the University of South Alabama. The photo shows an image of her presentation slide of her as a child sitting on the steps of her home in Georgia.https://jagworks.southalabama.edu/freedom-rider-browning_photos/1005/thumbnail.jp
Joan Browning Presentation Photo 5
No full textMs. Browning speaking during her presentation at the University of South Alabama. The photo shows an image of her presentation slide of her at 19 years old during her time as a Freedom Rider.https://jagworks.southalabama.edu/freedom-rider-browning_photos/1007/thumbnail.jp
USA Libraries Newsletter - v. 1, no. 1 (Fall 2025)
No full textLibrary News
What’s new at USA Libraries?
Library Personnel News // Lorene Flanders
Welcome to Vivienne Auvil! // Gail Kouame
Fall Semester at the Marx Library // William Baker & Kaitlyn Moody
Fall Semester at the MCOB Library // Amia Baker
The Healing Arts Exhibition at the Biomedical Library // Gail Kouame
USA Libraries Hosts ACHE NAAL OER Conference // Lorene Flanders
Summer Seminar & Professional Development // Muriel Nero
USA Libraries & LifeSouth Celebrate a Milestone // Heather Hoven-Glass
McCall Library Public Tours // McCall Archives
In Memoriam: Robert “Robbie” Runderson // Ellen Wilson Research Round-Up
Spotlighting library tips, tricks, and tools…
Graphic Medicine at the Biomedical Library // Leesha Coleman
Virtual Reading Room Service at the McCall Library // McCall Archives
Making Space for the Future: A New Look for the Marx Library // William Baker Odds & Bookends
Other library related miscellany...
The Unsung Role of the USA Libraries’ Student Workers // William Baker
It Takes a Village (Of Librarians): A Doctoral Student’s Library Story // Abby Hagood-Dokter
Book Review - The God of the Woods by Liz Moore // Sarah Rocha Faculty & Staff Spotlight
Highlighting the professional accolades of the USA Libraries.
Awards/Grants/Fellowships
Publications
Presentations
Conferences
Other Continuing Educatio