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Articles 2401 - 2430 of 291657
Full-Text Articles in Physical Sciences and Mathematics
Toward Learning-Based Reconstruction And Part Decomposition Of Man-Made 3d Geometry: Neural Implicit Representations And Scalable Supervision, Shen Fan
Dissertations
Digital three-dimensional (3D) models are central to engineering design, analysis, and manufacturing, but learning pipelines for man-made geometry often operate on sampled carriers that do not preserve all of the structure present in exact CAD representations. This dissertation studies learning-based reconstruction and part decomposition for structured man-made 3D geometry, from general object benchmarks to CAD-derived datasets, with a focus on neural implicit representations trained from signed-distance samples, point clouds, and tessellated meshes. The goal is to make these models more accurate, more part-aware, and more consistently supervised.
First, signed distance function (SDF) reconstruction with implicit neural representations is improved through …
Anonymity And Accountability In Secure Messaging, Erin Kenney
Anonymity And Accountability In Secure Messaging, Erin Kenney
Dissertations
Encypted messaging has become more and more prevalent as time moves on, and its benefits in assuring privacy cannot be overstated, but it also brings along with it concerns on how to moderate platforms where all messages are hidden. Message Franking, followed by Traceback systems, addressed these concerns by allowing the sender of a message to be proven when reported, even for forwarded messages in the case of Traceback, however these systems damage the privacy guarantees that originally motivated encrypted messaging to begin with.
In practice, even without those concerns encrypted messaging alone is not enough to prevent the most …
Parameter Density Estimation For Cardiac Electrophysiology Models Using Data Consistent Deep Learning, Michael Luo
Parameter Density Estimation For Cardiac Electrophysiology Models Using Data Consistent Deep Learning, Michael Luo
Dissertations
Mathematical models of biological rhythms and excitable systems can provide insights into mechanisms underlying cardiac electrical dynamics. However, estimating the parameters of these models from experimental observations is often difficult due to noise, heterogeneity, and unobserved variables. For example, in an electrocardiogram (ECG) recording, information about the electrical properties of different regions of the heart is compressed into a single voltage trace. Additionally, variability within these signals may contain important information about population heterogeneity, regional differences in electrophysiology, and time-dependent modulation.
This dissertation develops, explores, and evaluates methods that perform feature-based distributional inference for complex nonlinear dynamical systems. The objective …
Re: Conditional Approval Letter For The Butte Priority Soils Operable Unit (Bpsou) 2026 Revised Draft Final Backfill And Cover Soil Quality Assurance Project Plan (Qapp) (Dated May 13, 2026), Molly Roby
Silver Bow Creek/Butte Area Superfund Site
No abstract provided.
Sound Detection Of Memory Leaks In Llvm Ir Programs Using Accumulation Analysis, Robert Blacha
Sound Detection Of Memory Leaks In Llvm Ir Programs Using Accumulation Analysis, Robert Blacha
Theses
Resource leaks occur when a limited resource such as memory is allocated by a program and needlessly held past the point of use. Leaks can lead to a degradation of services which can be specifically triggered with malicious behavior, for example abusing a memory leak in a program to cause a server to slow down and crash for a denial-of-service attack.
Prior work has demonstrated that accumulation analysis provides a sound detection of resource leaks with a working implementation for programs written in Java. While useful, current implementations are limited to programs written in Java, which has a garbage collector, …
Adaptive Multimodal Smart Home Control On A Raspberry Pi 5 Using Hand Gestures, Voice Cues, And User Feedback, Vaibhav Bora
Adaptive Multimodal Smart Home Control On A Raspberry Pi 5 Using Hand Gestures, Voice Cues, And User Feedback, Vaibhav Bora
Theses
A real time multimodal smart home control system deployed on a Raspberry Pi 5 is presented. The system combines hand gestures, short voice cues, and proximity aware interaction to execute household commands such as light brightness control, fan speed adjustment, and stop or kill switch actions. Lightweight gesture and keyword spotting voice classifiers were trained offline and exported to TensorFlow Lite for efficient on device inference. For more natural spoken phrases, the system additionally integrates a locally deployed pretrained offline ASR component rather than a speech recognizer trained from scratch. Using a USB camera and microphone, the system operates fully …
Robustness Of Ai-Driven Histopathology Under Real-World Adversarial Examples, Ruchik N. Yajnik
Robustness Of Ai-Driven Histopathology Under Real-World Adversarial Examples, Ruchik N. Yajnik
Theses
This robustness of histopathology classification models under adversarial and real-world perturbations resembling clinical artifacts is being investigated.
Using whole-slide images from the CAMELYON17 cohort, four representative architectures—ResNet-18, ResNet-50, HIPT-2MLP, and ViT-B/16 —are benchmarked across controlled pixel-level distortions and artifact-like transformations. Adversarial methods include iterative Fast Gradient Sign, Projected Gradient Descent, Salt-and-Pepper noise, and the Adversarial Watermark—Stain Shift (AWSS). Three defense strategies—Randomized Smoothing, Adversarial Training, and an Artifact Detector—are evaluated for their ability to preserve diagnostic accuracy and model reliability. Structured perturbations consistently degrade performance, with transformer-based models showing the greatest sensitivity. The benchmark developed here offers a reproducible framework for …
Streamlined Biomedical Image Processing Pipelines, Jiehyun Kim
Streamlined Biomedical Image Processing Pipelines, Jiehyun Kim
Graduate Doctoral Dissertations
This dissertation focuses on advancing carotid artery analysis through a series of visualizations and deep learning tools for calcified plaque assessment and related biomedical imaging tasks. Accurate plaque evaluation is essential, but current workflows depend on slow, clinician-dependent manual review. To address these limitations, this work introduces the CACTAS framework, a set of tools and methods that enable fast and reliable plaque segmentation for clinicians.
The first study, the CACTAS-Tool, provides a web-based labeling tool that enables clinicians to label plaque directly in three dimensions through a streamlined one-click interface. This tool significantly reduces the effort required to generate high-quality …
Static Data-Race Detection For Gpu Programs: Behavioral Types With Partial Completeness Guarantees, Zhen Rong Liew
Static Data-Race Detection For Gpu Programs: Behavioral Types With Partial Completeness Guarantees, Zhen Rong Liew
Graduate Doctoral Dissertations
GPUs are essential to modern computing but notoriously difficult to program correctly. Static analysis tools can verify data-race freedom, but their over-approximations produce spurious reports of data races that do not occur, limiting their practical usefulness. This dissertation establishes when Memory Access Protocols (MAPs), a compositional abstraction modeling memory access behavior between synchronization barriers, can be simultaneously sound and complete. We first prove that MAP-based analysis is sound and complete for well-typed Jaminan programs---those without data-dependent array indexing. This result establishes the theoretical boundary: completeness is achievable when data-dependent control flow and indexing are absent. Jaminan extends MAPs with symbolic …
Small Molecule Antioxidants As Potential Therapeutics For Preeclampsia, Maxim Mastyugin
Small Molecule Antioxidants As Potential Therapeutics For Preeclampsia, Maxim Mastyugin
Graduate Doctoral Dissertations
The major goal of this work was to develop a therapeutic intervention against preeclampsia (PE). Preeclampsia affects up to 5-7% of all pregnancies and has no causative treatments. It is associated with oxidative stress caused by a prolonged ischemic state and increase in reactive oxygen species (ROS) in the placenta. The cardinal symptoms include high blood pressure, kidney dysfunction, and in severe cases, eclampsia. With no treatment for the underlying causes available, we offer small molecule antioxidants which may scavenge ROS in the placenta arising from the initiating event of PE, the oxidative stress. By reducing placental ROS, these antioxidants …
Computer-Aided Development Of Novel Antioxidants, Rita Bernadett Vlocsko
Computer-Aided Development Of Novel Antioxidants, Rita Bernadett Vlocsko
Graduate Doctoral Dissertations
Physiological redox homeostasis is a fine balance between prooxidants and antioxidants that are integrated elements of several reduction-oxidation mechanisms at molecular, organellar, cellular and tissue levels. When this equilibrium is disrupted and prooxidants become dominant, the body relies on endogenous and exogenous antioxidants to counterbalance the dysregulation and ultimately prevent the progression of oxidative stress. Reactive species (reactive oxygen species, reactive nitrogen species, or reactive sulfur species) are significant contributors to prooxidant activity. Over the years, substantial knowledge has been accumulated regarding their origin and roles in disease development, leading to the discovery and development of antioxidants that effectively target …
Role Of Technical Assistance In Pollution Prevention In Massachusetts Craft Breweries, Shubhechchhya Regmi
Role Of Technical Assistance In Pollution Prevention In Massachusetts Craft Breweries, Shubhechchhya Regmi
Graduate Masters Theses
This study aims to examine pollution from Massachusetts craft breweries, and if it can be lessened through a pollution prevention program. This study analyzed data from two assessments with the aim of analyzing the role of technical assistance in pollution prevention across eight impact categories. The first assessment was conducted on 29 MA breweries between 2022 and 2024, and 23 were assessed a second time (in summer 2024 and summer 2025). Craft breweries face several constraints in adopting pollution prevention practices the pollution prevention program known as BetterBev helps to bridge this gap by providing technical assistance, identifying inefficiency practices …
Polarimetric Terahertz Imaging For The Measurement Of Birefringence In Plastic, Rachel Cohen
Polarimetric Terahertz Imaging For The Measurement Of Birefringence In Plastic, Rachel Cohen
Theses
Birefringence offers a promising way to observe stress concentration in materials such as glass and plastic, and thereby to identify weaknesses. Polarimetric imaging can be used to measure the birefringence of material, so long as the material is transparent to the light being used for the imaging. In this research, 2D Terahertz imaging was investigated as a means of measuring the birefringence of plastics that are opaque to visible light but transparent to THz radiation, for the eventual purpose of analyzing the residual stress present. In order to do so, two separate terahertz cameras were characterized for potential use in …
Pypitfall: Dependency Chaos And Supply Chain Vulnerabilities In Python, Jacob Mahon
Pypitfall: Dependency Chaos And Supply Chain Vulnerabilities In Python, Jacob Mahon
Theses
Python software development heavily relies on third-party packages. Direct and transitive dependencies create a labyrinth of software supply chains. While it is convenient to reuse code, vulnerabilities within these dependency chains can propagate through dependencies, potentially affecting downstream packages and applications. PyPI, the official Python package repository, hosts many packages and lacks a comprehensive analysis of the prevalence of vulnerable dependencies. PyPitfall, a quantitative analysis of vulnerable dependencies across the PyPI ecosystem, is introduced. The dependency metadata of 378,573 PyPI packages is analyzed. 4,655 packages that explicitly require a known vulnerable package version and 141,044 packages that permit a vulnerable …
Re: Approval Letter For The Draft Final 2026 Butte Priority Soils Operable Unit (Bpsou) Type B Borrow Material Submittal #3 (Dated May 6, 2026), Molly Roby
Silver Bow Creek/Butte Area Superfund Site
No abstract provided.
Simulating The Movement Of A Major League Fastball, Max M. Moss
Simulating The Movement Of A Major League Fastball, Max M. Moss
Graduate Masters Theses
The orientation of the seams on a baseball may seem arbitrary in nature; however, they play an enormous role in the aerodynamics of the ball during its short flight to home plate. This thesis aims to model the movement of a four-seam fastball as accurately as possible using the fourth order Runge-Kutta method. The model incorporates the effect of the seams on the path of the ball by utilizing the oscillating cross-sectional area, which varies for each angle of rotation. The simulated results demonstrate a strong agreement with the observed pitch trajectories, accurately reproducing both induced vertical break and horizontal …
Electrospun Nanofiber Scaffolds For In Vitro 3d Tissue Engineering, Victoria E. Santillan, Samerender Nagam Hanumantharao, Stephanie Bule, Ronish M. Shrestha, Carter Rodzik, Alan Mendoza Estrada, Stephen L. Farias, Marina Tanasova, Smitha Rao
Electrospun Nanofiber Scaffolds For In Vitro 3d Tissue Engineering, Victoria E. Santillan, Samerender Nagam Hanumantharao, Stephanie Bule, Ronish M. Shrestha, Carter Rodzik, Alan Mendoza Estrada, Stephen L. Farias, Marina Tanasova, Smitha Rao
Michigan Tech Publications
Tissue engineering is widely used in research for investigating cellular proliferation, behavior, and responses to various stimuli. However, the predictive value of preclinical studies using cell culture plates is limited by the inability to recapitulate the complexity of the physiological microenvironment. Synthetic three-dimensional (3D) scaffolds can be engineered to mimic the complex morphology of the extracellular matrix of native tissues and can serve as physiologically relevant platforms for preclinical studies. In this study, 3D electrospun scaffolds were characterized to aid in breast cancer research. Unlike previous studies that focused primarily on scaffold fabrication or cell viability, this work systematically evaluates …
Mri-Based Deep Learning Radiomics Model For Automated Classification Of Disc Degeneration In The Lumbar Spine, Shiv Patil, Om Gandhi, Mert Karabacak, Matthew Carr, Konstantinos Margetis
Mri-Based Deep Learning Radiomics Model For Automated Classification Of Disc Degeneration In The Lumbar Spine, Shiv Patil, Om Gandhi, Mert Karabacak, Matthew Carr, Konstantinos Margetis
Student Papers, Posters & Projects
Disc degeneration in the lumbar spine is a major cause of low back pain (LBP). The accurate grading of disc degeneration on magnetic resonance imaging (MRI) is critical for clinical management and patient selection for spine surgery. This study aims to develop and evaluate machine learning (ML) models that combine features from deep learning (DL) and radiomics for the automated prediction of Pfirrmann grade (PG), a measure of disc degeneration, using multi-parametric lumbar spine MRI. Sagittal T1, T2, and T2 SPACE MRIs of 218 patients with LBP were acquired from the SPIDER dataset. For each intervertebral disc and available sequence, …
Developing A Framework For Mooc Dropout: The Role Of Utilitarian And Hedonic Values In Student Retention, Bipllab Roy, Mave D'Souza, Madhura Laghane
Developing A Framework For Mooc Dropout: The Role Of Utilitarian And Hedonic Values In Student Retention, Bipllab Roy, Mave D'Souza, Madhura Laghane
Northeast Journal of Complex Systems (NEJCS)
Massive Open Online Courses (MOOCs) have expanded access to higher education but continue to face persistently high dropout rates, raising concerns about their long‑term effectiveness and sustainability. This study develops and empirically tests a structural framework that links utilitarian values (perceived usefulness, certificate value, time flexibility), hedonic values (enjoyment, variety and novelty, personal interest alignment), and individual characteristics (goal orientation, self‑efficacy, motivation type) to MOOC student retention. Data were collected through a structured questionnaire administered to 200 MOOC learners from Christ University, Lavasa Campus, and analyzed using Structural Equation Modelling (SEM) in AMOS. The results show that goal orientation, self‑efficacy …
Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood
Fate Of Nitrogen Applied To Grassland In Animal Wastes, M Sherwood
IGC Proceedings (1977-2023)
The experiment was designed to determine the effects of land spreading of animal manures on the nutrient content of surface runoff water and infiltrating soil water. This report deals only with nitrogen (N) and attempts to quantify the losses through runoff, leaching, and volatilization of ammonia (NH3) as well as N uptake in the grass over a 3-year period. Experimental plots sited on grassland, on two soil types (a moderately drained loam and an impermeable gley), were equipped to collect surface runoff water. Ceramic probes were installed in each plot at 15-, 30-, 60-, and 100-cm depths to extract infiltrating …
Annual Losses Of Ammonia From A Grazed Pasture Fertilized With Urea, V R. Catchpoole, L A. Harper, R J.K Keyers
Annual Losses Of Ammonia From A Grazed Pasture Fertilized With Urea, V R. Catchpoole, L A. Harper, R J.K Keyers
IGC Proceedings (1977-2023)
Nitrogen-balance studies have shown losses of applied nitrogen (N) from grazed pastures in southeastern Queensland. Losses as high as 80% have been observed from urea N broadcast at 376 kg N/ha/yr over 8 years on a Setaria sp1uu:elata cv. Nandi pasture. Management techniques aimed at reducing this loss and thereby increasing the efficiency of use of N by pastures cannot be devised until the pathways of loss are known. The objective of this research was to estimate the annual ammonia (NH3) loss by convective transport from a urea-fertilized pasture at Samford Pasture Research Station in southeastern Queensland. Urea was broadcast …
Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney
Nitrogen Losses From Urine-Affected Areas Of A New Zealand Pasture, Under Contrasting Seasonal Conditions, P R. Ball, D R. Keeney
IGC Proceedings (1977-2023)
Grazing ruminants aggregate large quantities of forage nitrogen (N) into urine patches. Pasture plots treated with urine N were studied to assess its fate under contrasting seasonal conditions: cool-moist (representing winter-spring); warm-moist (late spring-early summer), and warm-dry (late summer-autumn). A permanent ryegrass (Lolium perenne L.)-white clover (Trifolium repens L.) sward on free-draining alluvial soil was studied. 'freatments were replicated in randomized blocks. Urine N was applied at 30 or 60 g N/m2• Relevant measurements were then continued until treatment differences disappeared. Apparent N balances for urine treatments were compiled. Fixation by white clover was always greatly reduced in …
Effects Of Grazing Management On Seasonal Variation In Nitrogen Fixation, J L. Brock, J H. Hoglund, R H. Fletcher
Effects Of Grazing Management On Seasonal Variation In Nitrogen Fixation, J L. Brock, J H. Hoglund, R H. Fletcher
IGC Proceedings (1977-2023)
Using the acetylene reduction assay, field studies in recent years have investigated the variation in N fixation in grazed systems, and some of the principles involved in the interaction with available soil N have been described. This experiment extends this work to include the effect of grazing management on the factors influencing N fixation. Two self-contained sheep-grazed units, one a 10-paddock rotationally grazed system and the other set stocked, were established on a high-fertility ryegrass-white clover pasture, with a basic stocking rate of 22 sheep/ha. Over the 1975-1978 period, both units were monitored for pasture growth, N fixation, and associated …
Symbiotic Nitrogen Fixation Of Alfalfa, Birdsfoot Trefoil, And Red Clover, G H. Heichel, C P. Vance, D K. Barnes
Symbiotic Nitrogen Fixation Of Alfalfa, Birdsfoot Trefoil, And Red Clover, G H. Heichel, C P. Vance, D K. Barnes
IGC Proceedings (1977-2023)
Forage legumes such as alfalfa (Medicago sativa L.), birdsfoot trefoil (Lotus comiculatus L.), and red clover (Trifolium pratense L.), grown in crop rotations, can provide an inexpensive source of nitrogen (N) to succeeding crops. Few quantitative measurements of seasonal patterns of N fixation in managed communities of perennial forage legumes have been undertaken, chiefly because of the lack of satisfactory methods. Therefore, there is little knowledge of how N fixation varies with crop development, yielding ability, and weather patterns. Quantitative measurements of N fixation are important in choosing the appropriate legume for use in a crop rotation and for …
Photosynthate Supply And Nitrogen Fixation In Forage Legumes, P M. Murphy
Photosynthate Supply And Nitrogen Fixation In Forage Legumes, P M. Murphy
IGC Proceedings (1977-2023)
Photosynthate supply is known to limit nitrogen fixation in legumes, and the resulting shortfall in energy supply necessary for maximum crop production may be aggravated by the energy-wasteful process of hydrogen (H2) evolution by the legume N2 fixing system. There is less information available on these aspects of the nitrogen-fixing process in forage legumes, such as white clover (Trifolium repens). The objectives of the present work were to determine how N2(C2H2) fixation and H2 production are influenced by carbohydrate supply in forage legumes.
Plants were grown under controlled environmental conditions, and nodule energy supply was varied by adjusting …
Selection Of Rhizobium Strains For Enhanced Dinitrogen Fixation In Forage Legume Production, C Hagedorn, W E. Knight
Selection Of Rhizobium Strains For Enhanced Dinitrogen Fixation In Forage Legume Production, C Hagedorn, W E. Knight
IGC Proceedings (1977-2023)
A set of procedures for the selection of Rhizobium strains for enhanced dinitrogen fixation in forage legumes is presented. Although forage legumes are among the most efficient members of the Leguminosae regarding biological nitrogen fixation (BNF), they are generally neither productive nor persistent without effective nodulation by appropriate rhizobia. The following methods define a selection and evaluation process to obtain appropriate Rhizobium strains. These include (1) regional survey of the production area, (2) strain collection and soil analyses, (3) strain characterization, (4) strain selection and manipulation, and (5) field evaluation of strains. The initial procedure is to survey the region …
Interactions Between Grasses And Rhizosphere Nitrogen-Fixing Bacteria, M H. Gaskins, D H. Hubbell, S L. Albrecht
Interactions Between Grasses And Rhizosphere Nitrogen-Fixing Bacteria, M H. Gaskins, D H. Hubbell, S L. Albrecht
IGC Proceedings (1977-2023)
Sorghum and Digitaria cultivars grown in soil or nutrient solutions were inoculated with a strain of Azospirillum in short-term greenhouse experiments. Carbon compounds lost by roots in solution culture experiments were determined in order to estimate the quantity of energy substrates that might be obtained by rhizosphere organisms from growing plants. Other plants were treated with plant growth hormones, and responses were compared to those of plants treated with killed Azospirillum cells. The similarity of the responses suggests that growth-hormone production by the inoculant organism, rather than nitrogen (N) fixation, is responsible for part or all of the increase in …
Simple Computer Simulation Models For Forage-Management Applications, G W. Fick, D Onstad
Simple Computer Simulation Models For Forage-Management Applications, G W. Fick, D Onstad
IGC Proceedings (1977-2023)
Dynamic computer simulation models of forage growth can be useful in interpreting physical and biological limitations on production and in designing management systems for testing in the field. The explanatory detail of such models makes them both more reliable and more expensive to use than simple empirical formulations. Simple simulation models reduce the expense. They can also serve as reference points for designing, evaluating, or selecting more complex versions and thus provide a more rational basis for using models in grassland research and management. Our objectives were to develop and to test a simple dynamic simulation model of alfalfa (Medicago …
Energy Flow And Conversion Efficiency In Grazing Grassland, T Akiyama, S Takahashi, M Shiyomi, T Okubo
Energy Flow And Conversion Efficiency In Grazing Grassland, T Akiyama, S Takahashi, M Shiyomi, T Okubo
IGC Proceedings (1977-2023)
Measurable energy storage on grassland ecosystems was examined for 5 years at the Fujinita site under the same rotation program with two grazing intensities. Daily global solar radiation and photosynthetic active radiation were measured as the energy sources in the ecosystem. Primary production by pasture plants and amount grazed by cattle were estimated by the biomass differences inside and outside of protection cages. For the estimation of energy produced or stored by plants or cattle, calorific values were examined for dominant plant species at the Fujinita site. Seasonal changes in digestibility were investigated to ascertain the energy of herbage digested …
A System Approach To Swedish Ley Production, J F. Angus, A Kornher, B.W R. Torssell
A System Approach To Swedish Ley Production, J F. Angus, A Kornher, B.W R. Torssell
IGC Proceedings (1977-2023)
A simulation model for estimating yield of leys from standard meteorological observations is described. It is based on an S-shaped growth curve also accounting for phasic development and regrowth depression. Effects of temperature, radiation, and soil moisture are accounted for by a growth index. Soil moisture is simulated with a standard water budget. The parameters in the model were estimated by comparing measured with calculated growth. The model then predicted final harvest with reasonable accuracy, but with underestimate of early season growth, presumably due to mobilization of carbohydrate from storage organs. Observed ley yields from 49 Swedish parishes (1961-1978) were …