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Predictive Modeling for Enhanced Truck Parking Information Systems Using Machine Learning
No full textThe growing demand for truck freight in the United States has intensified the shortage of truck parking, posing safety and operational challenges. While real-time Truck Parking Information and Management Systems (TPIMSs) offer current availability, predictive insights remain limited. This study develops hybrid machine learning and deep learning models to forecast truck parking utilization for both pretrip and en-route decision-making. A site-specific gradient boosting model achieved the best pretrip performance (average root mean square error [RMSE] = 0.154), while a long short–term memory–based truck parking site utilization prediction (TPSUP) model provided accurate en-route predictions (RMSE = 0.0429) with a one-hour horizon. To enhance usability, a “Popular Times” panel was designed to visualize predictions through intuitive, color-coded charts. These tools support safer and more efficient parking decisions, laying the groundwork for a more robust and predictive TPIMS.This article is published as Yang, Yilun, and Jing Dong-O’Brien. "Predictive Modeling for Enhanced Truck Parking Information Systems Using Machine Learning." Journal of Advanced Transportation 2026, no. 1 (2026): 9968995. doi: https://doi.org/10.1155/atr/9968995.This work was supported by the Iowa Department of Transportation
Ambiguity-free geometric approach to deep space navigation using angles-only measurements
No full textThis paper presents a method for simultaneous deep-space navigation and attitude determination using angles-only measurements. Using planetary ephemerides and observations of three known celestial bodies in the spacecraft body frame, a geometric construction is developed to derive an equation for the spacecraft’s distance to one body. The derivative of the associated zero-finding function is obtained for Newton’s method, enabling efficient equation solving. A sign ambiguity arises in the process, yielding nine possible combinations; a resolution strategy is proposed to identify the correct solution. Once the distance is determined, the spacecraft’s position is triangulated in the inertial frame, after which any attitude determination algorithm can be applied using the body measurements. The method eliminates the need for matrix inversions and employs a computationally efficient Newton's iteration, making it suited for on-board navigation. Numerical examples, simulating measurements of the Sun and two additional celestial bodies, demonstrate the proposed approach, and an accuracy analysis is conducted considering measurement uncertainties
The cytochrome P450 pathway and its role in inflammation during severe bovine coliform mastitis
No full textBovine mastitis is an inflammatory disease of the mammary gland, primarily driven by bacterial pathogens in the dairy environment, and is exacerbated by exposure during milking. As the costliest disease affecting the dairy industry, mastitis results in losses from reduced milk yield, treatment expenses, and animal replacement. The host innate immune response is crucial for pathogen clearance, with neutrophils serving as the primary early effector cells through phagocytosis, degranulation, and the release of neutrophil extracellular traps (NETs). Despite recent identification of oxygenated lipid mediators derived from the cytochrome P450 (CYP450) and soluble epoxide hydrolase (sEH) pathways during bovine coliform mastitis, the functional contribution of this metabolic pathophysiology remains undefined. To define temporal pathway dynamics as a foundation for therapeutic development, experimental systemic mastitis was induced in six lactating Holstein cows using intramammary infusion of 400 CFU of P4 Escherichia coli. Localized increases in CYP450 lipid products were detected in infected milk by 6 hours, followed by secondary metabolite elevation at 12 h. Mammary sEH enzymatic activity peaked at 6 hours, preceding the onset of systemic clinical signs. To assess pathway manipulation in vitro, whole blood and PBMCs from healthy lactating Holstein donors were stimulated with LPS, with co-treatment using the sEH inhibitor t-TUCB or exogenous epoxy fatty acids (EpoxyFA). LPS provoked IL-1β responses, and sEH inhibition selectively reduced IL-1β and TNF-α in PBMCs but not whole blood. EpoxyFA supplementation produced no measurable cytokine modulation. These preliminary results suggest a context-dependent anti-inflammatory effect of sEH blockade in bovine PBMCs, supporting continued refinement of the model and strategic deployment of inhibitors during early infection
Application of digital twin to the utility sector of the civil engineering industry
No full textThis study investigated the application of digital twin technology in the utility sector of the civil engineering industry. The study proposes the adoption of digital twins in the utility sector to solve the problem of poor asset management and poor productivity in the industry. The study began by first understanding the state of practice of digital twins in the civil engineering industry. Then, it proceeded to understand the specific existing implementation of digital twins in the utility sector. It was discovered that digital twin in the civil engineering industry was generally used for facility, infrastructure, and disaster management. In terms of specific existing implementations of the technology in the utility sector, it was discovered that the digital twin was a relatively new technology in the utility sector, with most past studies focusing on developing a framework for its implementation and reporting a few case studies for its implementation. It was also discovered that most existing implementations of the digital twin in the utility sector were at low maturity levels, depicting only geometric or 3D information, and that the water utility sector had the most advanced implementation of the digital twin.
Once the state of practice of digital twins was established, the study proceeded to evaluate the potential financial benefits of implementing digital twins in the utility sector to show the value it could bring if it were widely adopted. In a small number of selected case interviews of current adopters of digital twins at various maturity levels, the study discovered that the benefit-cost ratio of implementing digital twins in the utility industry was estimated to range from 1to 1422, showing the potential benefits possible in the utility sector. The benefits and costs were further modeled using a Monte Carlo simulation to show the level of uncertainty in the values obtained. The benefits appeared more pronounced at higher levels of maturity than at lower levels of maturity. The study also identified other benefits of digital twin to the utility sector asides from monetary value, including increased accuracy, better coordination, better communication, improved visibility of decisions, and reduced waste.
Finally, the study identified barriers or obstacles that could prevent the adopting of digital twin technology in the utility sector. Existing barriers from previous implementations of digital twin were obtained from the literature, and experts in the utility industry were asked to rank the barriers regarding relevance/significance to the utility sector. The responses from the experts were subjected to statistical tests, including the Friedman test, the Wilcoxon signed-rank test, and descriptive statistics to establish the most significant barriers. It was discovered that the most prominent barriers were financial/resource constraints, time and technical complexity of digital twin implementation, organizational/cultural resistance, and data management/expectation setting. Therefore, it was recommended that for digital twins to achieve hitch-free adoption, stakeholders must use innovative financing techniques such as public-private partnerships or phased implementation to overcome financial hurdles. For successful implementation, stakeholders in the utility sector must also invest in workforce upskilling, adopt open standards to overcome interoperability issues, and invest in information technology infrastructure capable of storing digital twin data
Hydrological and biophysical controls on nitrogen fate and nitrous oxide emissions in the Midwest Corn Belt
No full textNitrogen (N) is fundamental to the productivity and profitability of agricultural systems. However, N fertilizer only has around 60% efficiency. This inefficiency is largely due to a mismatch between soil N availability in the soil and crop N demand. One of the important pathways of N loss is through denitrification, which releases gases such as nitrous oxide (N₂O). N₂O is a highly potent greenhouse gas with greenhouse gas potential 300 times greater than carbon dioxide (CO2). This loss is becoming increasingly important as climate change increases. A deeper understanding of the mechanisms driving these losses is critical for developing sustainable solutions.
This dissertation investigates how soil moisture and temperature regulate the timing and mechanisms of N loss and N₂O emissions in Midwestern maize systems. Using statistical analysis, field observations, and a controlled laboratory experiment, the three chapters collectively map the temporal mismatch between N availability and demand, the controls on winter N₂O fluxes, and the role of saturation duration in driving dissolved N₂O dynamics.
First, I used a growing degree day (GDD) framework to quantify the asynchrony between soil N depletion and crop N demand. I found soil N availability peaks well before maize demand, causing a considerable amount of loss of reactive N pools exposed to leaching and gaseous losses like N₂O. Second, I used a field study to measure surface N₂O flux and pool size from 0-60 cm and test supporting soil factors. I found that cumulative freezing degree days (FDD), rather than instantaneous temperature, best explain subsurface N₂O production and emission. Weather-year has a more important influence than treatment. Third, I conducted a controlled column experiment to understand how prolonged saturation affects N₂O production and emission. I found that prolonged saturated soil condition amplifies N₂O production and post-drainage release. In addition, I found that dissolved N₂O in drainage water from our experiment was 30 times higher than reported in the literature, indicating that indirect N₂O loss through drainage water is an important but often overlooked pathway.
In total, my findings provide a better understanding of the fundamental mechanisms that connect thermal time and hydrology to biophysical N cycling of to better measure and predict N₂O emissions. This work improves our ability to predict when and where N is most vulnerable to loss, thereby guiding better fertilizer timing, drainage management, and understanding of greenhouse gas mechanisms. Ultimately, these insights represent critical steps toward building more climate-resilient and efficient agricultural systems
Water access, quality mistrust, and public health: Understanding water insecurity and inequities in the United States
No full textWater insecurity, defined as inadequate, unreliable, or unaffordable access to safe water for a healthy life, is a global challenge that persists in the United States despite the nation’s wealth and infrastructure investments. While federal programs such as the Public Works Administration in the early twentieth century and the Safe Drinking Water Act of 1974 expanded water services and improved safety standards, millions of U.S. residents continue to face barriers to safe and sufficient drinking water. These inequities are concentrated in marginalized communities and are most visible across three dimensions of water insecurity: access to complete in-home plumbing, water quality mistrust, and water-related public health impacts.
Water access remains uneven. Although the number of households without complete plumbing has declined over time, approximately 500,000 households still lack hot and cold piped water, a sink, and a flush toilet. These “plumbing-poor” households are disproportionately located in low-income, minority, rural, and Tribal communities. Urban centers also reveal disparities, where renters, mobile home residents, and households of color are significantly more likely to lack piped water. Along the U.S.–Mexico border, colonias remain severely under-served, forcing residents to rely on polluted wells and hauled water, while in the Navajo Nation nearly one-third of households haul water from long distances. Rural Alaska, home to many Alaska Native communities, represents the starkest case, with thousands of homes unserved and dependent on centralized washeterias or hauled water. These access inequities translate into daily physical and financial burdens, reduced water use, and heightened vulnerability to infectious disease.
Water quality also shapes water insecurity, particularly through the issue of trust. While regulatory compliance under the Safe Drinking Water Act provides technical assurances of safety, lived experiences tell a different story. Communities often distrust tap water due to its taste, smell, or appearance, or because of repeated system failures and historical neglect. High-profile crises such as the Flint, Michigan lead contamination and Hurricane Maria in Puerto Rico revealed how quickly trust in water systems can erode, especially among low-income and minority households. In rural Alaska, distrust of treated water drives reliance on traditional sources such as rivers, springs, and snowmelt, which are culturally significant but often untreated. Mistrust can lead to bottled water dependence, with financial strain and exposure to microplastics, or substitution with sugar-sweetened beverages, which has been linked to elevated diabetes rates in Alaska Native communities.
The health consequences of these inequities are well documented: higher rates of gastrointestinal illness, respiratory infections, and skin conditions in unserved Alaska Native villages; increased exposure to hepatitis A and other diseases in colonias; and poor mental health outcomes associated with water shutoffs and unsafe alternatives in U.S. cities. Yet despite growing recognition that water insecurity in the U.S. undermines both physical and mental health, significant gaps remain. Most studies focus on isolated communities or crisis events, rarely considering cultural context, trust in water systems, or national patterns over time. Few directly link incomplete plumbing to measurable health outcomes, and fewer still apply methodological approaches that meaningfully include Indigenous governance systems and community perspectives. Together, these challenges underscore the need for research that integrates water access, water quality, and health inequities, while also centering community voices and cultural context. This dissertation addresses that need by focusing on Alaska as a critical case study and situating its findings within the broader U.S. landscape of water insecurity.
This dissertation presents an in-depth study focused on understanding water insecurity in the United States, with Alaska as a critical case study and national-scale analysis providing broader context. The dissertation is structured into three main chapters, each exploring different aspects of water insecurity.
Chapter 2 examines how community-based participatory research (CBPR) can be applied to water insecurity research in rural Alaska Native communities, posing the question: How can CBPR ensure that water research reflects Alaska Native cultural values and priorities? The methodology involves a descriptive case study of a water insecurity research project in Unalakleet, Alaska, analyzing the processes of community approval, collaboration, and co-learning that guided the project. The findings show that while Alaska Native communities face persistent challenges of incomplete plumbing, reliance on washeterias, and prohibitive infrastructure costs, CBPR provides a framework for centering cultural values, building trust, and empowering communities to actively shape solutions. This chapter highlights both the successes and challenges of applying CBPR on the ground and contributes a framework for researchers and engineers seeking to conduct culturally grounded water insecurity research.
Chapter 3 of the dissertation shifts to the dimension of water quality by investigating the conditions shaping trust in multiple water sources in Unalakleet. It answers the question: How do combinations of technical, cultural, and social conditions produce trust or distrust in drinking water sources? The methodology involves in-person interviews with 63 residents (96.8% Alaska Native), whose responses about seven water sources (tap, bottled, wells, rainwater, snowmelt, rivers, and lakes) were coded into fuzzy sets capturing organoleptic qualities (taste, odor, color), perceptions of treatment, Traditional Ecological Knowledge (TEK), social influence, environmental impacts, and health concerns. Fuzzy-set Qualitative Comparative Analysis (fsQCA) was then applied to identify the combinations of these conditions leading to high or low trust. The findings demonstrate that trust in treated sources such as tap and bottled water depended on positive organoleptics and perceptions of treatment, while trust in traditional sources such as wells, snowmelt, and rainwater was grounded in TEK and social influence. Organoleptics consistently emerged as a core condition across all sources. This chapter advances methodological approaches to water insecurity research by showing that trust cannot be understood through single variables but rather emerges from distinct configurations of technical, cultural, and social conditions.
Chapter 4 expands the focus to the national scale to examine the relationship between incomplete plumbing and health outcomes across U.S. counties. It poses the question: How does plumbing poverty shape population health, and where are these inequities concentrated geographically? The methodology involves longitudinal regression analysis and spatial mapping using data from the American Community Survey (ACS) and the County Health Rankings and Roadmaps (CHR&R) between 2018 and 2021, covering 3,143 counties with over 12,000 observations. Incomplete plumbing—defined as lacking hot and cold running water, a sink with a faucet, or a flush toilet—was analyzed alongside measures of physical and mental health, with controls for social vulnerability, income inequality, and demographics. The findings show that plumbing poverty is geographically clustered in Alaska, Texas, Appalachia, and the rural South, and that counties with higher levels of incomplete plumbing consistently report worse physical and mental health outcomes. By linking plumbing disparities to measurable health inequities, this chapter situates Alaska’s challenges within a broader pattern of infrastructural inequality in the United States and demonstrates the need for targeted interventions in the communities most affected.
This dissertation makes important contributions to both scholarship and practice by advancing understanding of water insecurity in the United States through the lenses of access, quality, and health. Practically, it offers concrete guidance for stakeholders working at multiple levels. For researchers and engineers, it provides a roadmap for conducting water insecurity projects in Alaska Native communities through community-based participatory research (CBPR), showing how tribal approvals, advisory boards, and co-learning processes can ensure research is culturally aligned, transparent, and sustainable. For water utilities and policymakers, it identifies the specific consumer indicators—such as taste, odor, and treatment confidence—that shape trust in treated water, and demonstrates how these can be addressed through improved communication, investment in infrastructure, and support for culturally preferred alternatives when safe. For decision-makers on the national scale, it highlights geographic clusters of plumbing poverty and links them to measurable health outcomes, offering clear evidence for where investment and resources should be directed to address systemic infrastructural inequities.
Theoretically, the dissertation extends the literature on water insecurity in several key ways. It contributes a CBPR-based framework that shows how collaborative research structures reshape both the process and outcomes of WASH research in Indigenous contexts. It introduces fuzzy-set Qualitative Comparative Analysis (fsQCA) as a methodological tool for studying trust in water systems, demonstrating that trust is not formed by single variables but through distinct configurations of technical, cultural, and social conditions. Finally, it expands theoretical understanding of water insecurity and health by showing that inadequate water access—measured through incomplete plumbing—operates as a structural determinant of both physical and mental health, adding a new dimension to research that has traditionally emphasized water quality. Taken together, these contributions provide both a methodological and substantive foundation for addressing water insecurity in ways that are culturally grounded, empirically robust, and responsive to health inequities
Optimization of soft magnetic alloys in Fe–Co and Fe–Si systems
No full textThe Fe–Co and Fe–Si soft magnetic materials (SMMs) are widely used in electrical and electromechanical systems such as transfomers, power devices, and motors, owing to their high saturation magnetization, high permeability and low coercivity. However, efciency limitations caused by core losses and processing-related constraints remain, emphasizing the need for materials that combine high magnetization, low coercivity, and high resistivity while maintaining good formability. Understanding how compositional tuning, alloying, and processing afect these properties is therefore essential for advancing the next generation soft magnetic materials.
In this dissertation, the phase stability, soft magnetic behavior, and electrical properties of multicomponent Fe–Co–Mn–Cr and Fe–Si–Ce/V alloys were investigated through a combination of frst-principles Korringa–Kohn–Rostoker–coherent potential approximation (KKR–CPA) calculations and experimental validation.
For the Fe–Co–Mn–Cr system, calculations revealed that the stability among bcc, fcc, and hcp phases depends sensitively on the balance between Fe/Co and Mn/Cr contents, with Mn and Cr acting as fcc/hcp stabilizers. Experimentally, controlled solidifcation, deformation, and annealing enable manipulation of metastable phase fractions, confrming that higher bcc stability correlates with enhanced saturation magnetization. The Fe40Co40Mn10Cr10 exhibited excellent workability through transformation-induced plasticity (TRIP) efect and achieved a high saturation magnetization of 2.01 T with low coercivity of 71 A/m after annealing. The presence of metastable phases not only enhanced ductility through the TRIP efect but also suggests an alternative pathway for designing soft magnetic materials that exploit controlled metastability. However, its electrical resistivity remained relatively low. The optimized composition, Fe42.5Co45.5Mn5.5Cr6.5, formed a single bcc phase with high magnetization (1.9 T), low coercivity (433 A/m), and high resistivity (85.4 μΩ · cm).
In the Fe–Si–based alloys, Ce and V additions were introduced to improve electrical resistivity. Ce promoted the formation of Ce-rich precipitates and lattice strain, which deteriorated magnetic performance, while V maintained a single bcc structure and increased resistivity through impurity scattering without signifcantly reducing magnetization. The optimal composition, Fe–6.5 wt% Si–0.5 wt% V, achieved the best balance between magnetic and electrical properties.
Overall, this work establishes a framework linking phase stability, metastability, and alloy chemistry to magnetic and electronic performance
Understanding how indie pattern-makers are building trust in virtual fitting software
No full textLearning sewing skills online is what many sewing enthusiasts are turning to in a digital age, and now for more than just sewing tutorials. Many now look to indie pattern-makers for downloadable sewing patterns to sew a variety of handmade items that are tailored to their preferred style and skillset. With the rise in popularity of digital sewing patterns, the sewing influencer, and DIY culture, more trust in virtual fitting software systems is growing within the indie pattern-maker community. Using the diffusion of innovation theory developed by Everette M. Rodgers (1962), this case study has been developed to understand how indie pattern-makers are building trust in virtual fitting software. This qualitative empirical research focuses on the lived experience of indie pattern-makers who are currently producing patterns through in-depth interviews and their beliefs and trust in using virtual fitting software
A Straightforward Fabrication Technique to Minimize Evaporation and Surface Fouling in Microscale PDMS Devices for Nucleic Acid Amplification by dLAMP
No full textNucleic acid amplification is a non-trivial step in genomic studies aimed at disease diagnosis. Microfluidics offers miniaturized platforms for handling small samples, yet heat-associated bioreactions such as dLAMP is challenging on PDMS-prototype devices due to its material characteristics including porosity and hydrophobicity. Network porosity enhances solution evaporation and diffusion of small molecules while the hydrophobicity encourages the biofouling of the surface. In this work, we present a facile and straightforward method to overcome these problems without requiring special technical expertise, reagents, or equipment. The porosity of PDMS was tuned by altering the conventional monomer-to-crosslinker ratio to demonstrate significant retention of solution even after 2 h of heating at 60 ℃ and to reduce the small molecule loss by 70%. To render surface hydrophilicity to PDMS, a dry-coating of commercially available surfactant, Tween-20 was used. The results indicate that the dry coating has superior functionality in enhancing the amplification efficiency while the same amount of the surfactant included in the solution dampens the efficiency. Through this combination approach, we demonstrate a 2-fold improvement in the LOD for nucleic acid amplification by dLAMP. By addressing key material challenges, this study advances PDMS-based microfluidics as a viable platform for high-precision nucleic acid quantification. These findings provide a cost-effective solution for improving lab-on-chip diagnostics, bridging the gap between microfluidic research and real-world clinical applications.This is a preprint from Rathnaweera, Thilini N., Darshna Pagariya, and Robbyn K. Anand. "A Straightforward Fabrication Technique to Minimize Evaporation and Surface Fouling in Microscale PDMS Devices for Nucleic Acid Amplification by dLAMP." (2026). doi: https://doi.org/10.26434/chemrxiv.10001794/v1.The authors gratefully acknowledge Warren Straszheim of Materials Analysis and Research Lab, Office of Biotechnology at Iowa State University for the SEM and EDS analysis and the
National Institute of Health for funding this project through a NIH NIBIB Early Career Trailblazer Award (1-R21EB028583-01)
Investigating interactions of insect pests with short-stature corn
No full textShort-stature corn, with innate lodging resistance, is being introduced to farmers in the United States. Development of short-stature corn hybrids creates additional areas of research related to pest management. Transgenic corn plants have been genetically modified to produce toxins derived from Bacillus thuringiensis (Bt), and short-stature hybrids will have the same Bt traits as current tall corn hybrids. To manage resistance, blended refuges, which contain a mixture of non-Bt plants and Bt plants within the same field, and Bt crop pyramids, which produce two or more Bt toxins, are frequently used. Little is known about how insect pests will interact with short-stature corn. In particular, it is important to anticipate if management of Bt resistance in insect pests will need to be modified for Bt short-stature corn. Therefore, a series of field studies were performed to compare insect interactions between short-stature vs. tall corn and Bt vs. non-Bt corn. One field study focused on movement and survival patterns of the larvae of western corn rootworm, Diabrotica virgifera virgifera, and European corn borer, Ostrinia nubilalis. A second field study was used to evaluate the survival and emergence patterns of adult corn rootworm (Diabrotica spp.). Lastly, a third field study was used to quantify Bt toxin production in plants from a blended refuge and the corresponding effect on the survival, development, and kernel injury of corn earworm, Helicoverpa zea, larvae. In most cases, insect interactions did not differ between short-stature corn and tall corn. When significant differences emerged between short-stature corn and tall corn, they were not consistent between treatments or years. Therefore, current resistance management strategies are expected to be similarly effective in short-stature corn. These data are useful for determining how interactions of these pests will influence the management of resistance in Bt short-stature corn