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Road Surface And Subsurface Monitoring Using Machine Learning
No full textThis thesis presents a comprehensive, non-invasive framework for real-time monitoring of road surface and subgrade conditions using acoustic sensing and machine learning. Traditional Tire-Road Coefficient of Friction (TRCF) estimation techniques often rely on intrusive sensors, offline data analysis, or laboratory measurements, making them impractical for real-time applications. The present research introduces an alternative approach that utilizes the acoustic emissions generated by tire-road interaction to infer both surface friction and subsurface integrity dynamically.Measurement microphones were mounted beneath a test vehicle to record tire-road noise signatures across different pavement textures and vehicle speeds. The collected acoustic signals were processed using Fast Fourier Transform (FFT) to convert them into the frequency domain, followed by Principal Component Analysis (PCA) for dimensionality reduction and feature extraction. PCA was employed to identify dominant frequency components and reveal underlying correlations between surface texture, subgrade stiffness, and vehicle speed. Principal Component (PC) vectors were generated and compared across multiple test locations and speeds to evaluate their sensitivity to varying road conditions. The comparison of PC vectors provided a clear distinction between smooth, intermediate, and rough pavement surfaces. Specifically, PC1 and PC2 captured the dominant energy components associated with tire-road contact dynamics, while higher-order components (PC3-PC5) represented minor variations and noise. The relative magnitude and orientation of PC vectors demonstrated consistent patterns that correlated with road texture classification, confirming PCA’s effectiveness in isolating meaningful spectral features from complex acoustic data. Experimental trials conducted on roads around the University of North Dakota including Washington Street, Cherry Street, and University Avenue, validated the proposed method. The PCA-based results revealed that variations in the principal components were consistent with changes in pavement roughness and subgrade response, with low-frequency components indicating subsurface weakening or moisture accumulation. Overall, this study establishes a scalable, data-driven approach for intelligent infrastructure assessment. By integrating acoustic sensing with unsupervised learning, the framework enables continuous estimation of road surface and subgrade conditions without intrusive testing. The findings have significant implications for real-time traction monitoring, autonomous vehicle safety, and predictive maintenance systems, providing a foundation for the next generation of smart transportation infrastructure
Microbial Communities And Host Plants Of Megachilidae In The Greater Grand Forks Area (GGFA)
No full textAlthough Megachilidae are important pollinators in the United States, there is still much to learn about the health and functionality of these bees. Megachilids are threatened by competition from non-native pollinators and other environmental factors. The species distribution and composition of the gut microbiome in megachilid bees are not well known for the Greater Grand Forks Area (GGFA). My research seeks to answer the questions: what megachilid species are in the GGFA, where are they, and what symbionts are in their gut microbiomes? I collected and identified solitary bee specimens from North Dakota and Minnesota, dissected their gut contents, and preserved samples for DNA analysis. DNA was extracted and amplified using PCR primers targeting mitochondrial (CO1), chloroplast (rbcL), and bacterial (16S) gene regions to identify bee species, plants, and gut microbes, respectively. I used Sanger and Illumina sequencing to identify microbes and plants to their lowest taxonomic level. I used BLAST to match Sanger sequences to identify megachilid bees; I ran the MOTHUR pipeline for quality control and to identify microbe strains. I used rarefaction, Shannon Diversity Indexes, ANOVA, and PERMANOVA to assess diversity and composition of plant and microbial communities across bee species. I identified nine species of Megachilidae with nearly equal representation of males and females collected via sweep netting. The gut microbiome analysis showed significant overlaps among species, with common bacteria from the Bacillota and Pseudomonadota, suggesting there is a core microbial community for Megachilidae. Plant DNA analysis revealed no significant differences in plant contents across species, likely due to shared habitat and foraging behavior, especially in landscaped areas. Limitations included small sample size, lack of pollen surface data, and sampling bias from collection methods, indicating the need for expanded sampling and complementary techniques. Protecting solitary bees helps ensure the resilience of both natural habitats and agricultural systems throughout our country. By identifying the plant species that megachilids visit, researchers and agronomists can better understand the ecological relationships between solitary bees and their habitats. This knowledge is crucial for informing conservation strategies, such as protection and restoration of native plant communities that support native bee populations. Ultimately, linking bee foraging behavior to specific environments helps ensure the survival of these important pollinators in the face of habitat loss and environmental changes
Babied for Life?: Helicopter Parents and College Students
No full textThis essay covers the effects of helicopter parents, or over-parenting, on college students. College students traditionally gain a new level of independence, and this essay explores how helicopter parents hinder that independence. This essay also explains some of the negative mental health effects over-parenting has on college students
Parade on Third Street, ca. 1910
No full textPhotograph taken taken on Third Street looking northeast . A lot of people are standing along the street in front of stores are watching as the parade goes by. Businesses in the background are the Ontario Store, McGrath Pharmacy, M.G. Olson Clothing, and the Hotel Ryan.https://commons.und.edu/gf-city-photos/1234/thumbnail.jp
Melvin Mellington Oppedgard
No full textUndated photograph of Melvin Mellington Oppegard. He was the editor and publisher for the Grand Forks Herald from 1929-1949,https://commons.und.edu/gf-city-photos/1252/thumbnail.jp
Ninwi Caya (Loves Life)
No full textThis art panel is part of the series 1800 Lakota Winyan (Lakota word for women) by Lorri Ann Two Bulls. Two Bulls said of this series, Each panel carries the name of a woman recorded in an 1800\u27s ledger as they arrived at the reservation. The paintings are my way of identifying the name of those women, winyan, who live on today and are still remembered.
Featured in the exhibition, Plain of Stars: An exhibition to uplift, acknowledge, and celebrate Indigenous students.https://commons.und.edu/native-art/1103/thumbnail.jp
But I Have Something to Say
No full textA woman is vacant of features with the exception of one eye and lines drawn over her face stares ahead as her bright red braids are suspended in the air. Where her mouth should be, there are mosaic squares that are similar the squares used to censor figures or faces on television.
Featured in the exhibition, Plain of Stars: An exhibition to uplift, acknowledge, and celebrate Indigenous students.https://commons.und.edu/native-art/1108/thumbnail.jp
Practice Climbing Loading Net
No full textFive troops scale up a loading net as a form of training. Title taken from photographer\u27s original album.https://commons.und.edu/infantry-photos/1091/thumbnail.jp