Physics Commons^™

Machine Learning-Based Regression For Magnetic Field Prediction From Odmr Spectral Data, Jesse B. Hernandez

Electronic Theses, Projects, and Dissertations

Optically Detected Magnetic Resonance (ODMR) using nitrogen-vacancy (NV) centers in diamond enables sensitive, room-temperature magnetic field sensing, but real ODMR spectra are often noisy and difficult to analyze with traditional peak-fitting methods. This thesis investigates whether machine learning can reliably predict magnetic field strength directly from ODMR spectra, and compares four model families under a single regression task: a random forest, an artificial neural network (ANN), a one-dimensional convolutional neural network (1D-CNN), and a Transformer.

Training data were generated from an NV-ensemble simulation calibrated to real measurements provided by the Ulsan National Institute of Science and Technology (UNIST), spanning 0 …

Pentagonal Pdte2 Monolayer For Sustainable Solar-Driven Hydrogen Production, Narender Kumar, Shambhu Bhandari, Dario Alfè, Ravindra Pandey, Nacir Tit

Michigan Tech Publications

This investigation demonstrates that the pentagonal PdTe2 (penta-PdTe2) monolayer is a highly tunable two-dimensional (2D) photocatalyst, characterized by the bandgap of 1.87 eV and high hole mobility. Using density functional theory calculations with the HSE06 functional, we show that tensile strain engineering (particularly at +2% and +3%) is essential for enabling spontaneous water splitting. At these strain values, the valence-band maximum and conduction-band maximum straddle the water redox potentials (H+/H2 and O2/H2O) under both acidic (pH = 0) and neutral (pH = 7) conditions. The monolayer's low hole effective mass facilitates rapid charge extraction, mitigating recombination and driving the oxygen …

Quantum Mechanics, Non-Locality, And The Space Discreteness Hypothesis, Wilson A. Zuniga-Galindo

School of Mathematical & Statistical Sciences Faculty Publications

The space discreteness hypothesis asserts that the nature of space at short distances is radically different from that at large distances. Based on the Bronstein inequality, here, we use a totally disconnected topological space X as a model for the physical space at short distances. However, we consider the time as a real variable. In this framework, the Dirac–von Neumann formalism can be used. This discreteness hypothesis implies that given two different points in space, there is no continuous curve (a world line) joining them. Consequently, this hypothesis is not compatible with the theory of relativity. We propose R×(R×X)3 as …

Noise Characterization And Mitigation In Intermediate-Scale Quantum Systems, Muhammad Qasim Khan

Dartmouth College Ph.D Dissertations

Current quantum processors, at the intermediate scale of tens to hundreds of qubits, remain error-limited. This thesis studies two related sources of error. The first is environmental noise, which may have temporal and spatial correlations and nonclassical components. The second is state-preparation and measurement (SPAM) error, which arises in the operations used to characterize this noise, a prerequisite for boosting operational fidelities. Neither can be characterized alone. Noise spectroscopy techniques use imperfect preparation and readout, while SPAM characterization is affected by qubit decoherence. Our methods vary measurement depth, drive duration, or sequence repetition so each source changes the measured signal …

A Systematic Approach For Controlling Tem Sample Thicknesses, Monte Kozell

Physics Faculty Publications and Presentations

Historically, TEM prep has been an artisan craft without a systematic workflow that ensures quantified control over TEM sample thickness. Over- and under-thinning is a significant problem in the TEM prep process. A direct measurement process was demonstrated to control the final thickness of the TEM lamella. Final lamella thickness was controlled by directly measuring lamella thickness in real time using a 10–15 kV SEM while performing secondary electron imaging at the mill position, allowing for (human-mediated) closed-loop processing. We demonstrated the utility of this technique by systematically thinning five TEM samples to discretely target thicknesses ranging from 100 nm …

Comparative Antibacterial Efficacy Of Hot Vs. Cold Aqueous Saussurea Costus Root Extracts Against Streptococcus Mutans, Fatima Adil Mohammed Hussien, Ahlam Taha Mohammed

Karbala International Journal of Modern Science

The present in vitro study assessed the antibacterial efficacy of aqueous root extracts prepared using hot and cold extraction methods of Saussurea costus against Streptococcus mutans isolates. Based on antibacterial screening results, the hot extract, which demonstrated greater antibacterial activity, was selected for subsequent cytotoxicity assessment. Cold and hot aqueous extracts were subjected to phytochemical screening, and phenolic acids and flavonoids were quantitatively assessed using High-Performance Liquid Chromatography. Antibacterial efficacy was evaluated using a resazurin-based microdilution technique to assess the minimum inhibitory concentration, followed by subculture to determine the minimum bactericidal concentration, and an agar well diffusion assay. Cytotoxicity of …

A Unified Sensitivity Kernel For Coherent Wave Tomography In Radar, Seismic, Ultrasound And Optical Imaging, Alexey Yamilov

Research Data

Overview:

This deposit contains the three figures of Ref. [1] that report numerical simulations, main-text Fig. 4 and Supplementary Figs. S1 and S2, together with the plotted data, one CSV file per figure. The simulations are described in Supplementary Note S3 of Ref. [1]. They were computed with MESTI [2] in two dimensions and with the modified Born series [3] in three, on the Mill [4] and Hellbender [5] clusters. The remaining figures of the paper are schematics (Figs. 1 and 5), a diagram drawn from the numbers listed in Table I (Fig. 3), or evaluations of closed-form expressions given …

Raman Spectroscopy Characterisation Of 5c Potency Of Homoeopathic Drugs Nux Vomica, Thuja Occidentalis And Nitricum Acidum, Alfonso Tramontana, Giuseppe Acri, Lucia Denaro, Massimo Mattozzi, Maria Antonietta D'Avanzo, Barbara Testagrossa

Indian Journal of Research in Homoeopathy

Background: The physicochemical characterisation of homoeopathic medicines remains a challenge. Raman spectroscopy is a promising tool for identifying structural modifications in the solvent matrix and specific vibrational ``fingerprints'' induced by the potentisation process. Objective: This study aimed to characterise three remedies (Nux vomica, Thuja occidentalis, and Nitricum acidum - 5C potencies) using Raman spectroscopy to identify specific vibrational markers and evaluate the technique's ability to differentiate between different preparations within a complex matrix. Materials and methods: The drugs were analysed as crushed granules (solid state) and after dissolution in betamethasone disodium phosphate (liquid state). Raman spectroscopy was …

A Calibrated And Conformal Deep Learning Framework For Trustworthy Antinuclear Antibody Pattern Recognition With Selective Referral To Experts, Hussein Ali Hussein Al Naffakh, Ahmed Dheyaa Radhi, Raghdah Maytham Hameed, Muntaha Abdullah Reishaan, Fouad A. Majeed, Rozaida Ghazali

Karbala International Journal of Modern Science

Reading antinuclear antibody patterns on human epithelial cells by indirect immunofluorescence is the reference screen for systemic autoimmune rheumatic diseases, but it is slow, subjective, and variable between observers. Deep learning reaches high accuracy on this task, yet most systems return a single prediction without stating how reliable it is, which is unsafe in a diagnostic workflow. This paper presents an intelligent decision support framework built around a single calibrated uncertainty signal. That signal is the control variable for four reliability modules: confidence calibration, conformal prediction, error detection, and selective referral. A feature space out of distribution detector serves as …

Exceptional Holography (2025 Renewal, Revised Budget), Oscar Varela

Funded Research Records

No abstract provided.

Cedar: Investigating The Mesosphere And Lower Thermosphere Neutral Temperature And Winds Responses To Geomagnetic Storms Equatorward Of The Auroral Zone, Tao Yuan

Funded Research Records

No abstract provided.

Analysis Of The Influence Of Anthropometric Dimensions Of Postural Ergonomics Using Multiple Linear Regression, Gashbeen Faisal Najmaddin, Edrees Muhammed Tahir Harki

Al-Bahir

Ergonomics is the study of designing and arranging a workspace or product to optimize the “fit” between people and their work, ensuring safety, comfort, and efficiency. The scientific literature indicates that ergonomic perspectives on the workplace are connected to the anthropometrics of societies. This study primarily aims to create a model that integrates multiple predictive variables to estimate the target variable. Multiple linear regression analysis is used to identify how different anthropometric dimensions predict postural ergonomics during prolonged sitting. Based on the regression models’ results, the predicted can be calculated using user anthropometry and existing chair dimensions. Furthermore, the primary …

On-Shell Compression And Reconstruction (Oscar) Of Monochromatic Wave Fields In Weakly Scattering Media, Pablo Jara, Alexey Yamilov

Research Data

Overview

This deposit contains one realization of each of the two simulation platforms of Ref. [1], a two-dimensional (2D) scalar field and a three-dimensional (3D) vector-field component, together with two self-contained Python scripts that perform On-Shell Compression and Reconstruction (OSCAR) on them. Each script Fourier-transforms the stored field, measures the shell radius from the spectrum, retains only the Fourier components inside the shell of full width α/ℓs around it for α = 1, 3, 5, 8, 12, reconstructs the field by the inverse transform, and plots the reconstructed intensities, panels (a)–(e), next to the original field, panel (f), on a …

Libs-Based Detection And Preliminary Classification Of Microplastic Signatures In Soil Samples., Ekhlas Jabir Mahmood

Al-Bahir

Contamination of terrestrial systems by microplastics (MPs) has become a critical environmental hazard, but detection of such contaminants in a complex soil system is a challenge for conventional analytical techniques. This research aims to assess the potential of Laser-Induced Breakdown Spectroscopy (LIBS) for the detection and differentiation of different types of microplastics, including HDPE, LDPE, PP, PS, and PVC, dispersed in the soil of Al Najaf, Iraq. Soil samples were collected from different functional zones, namely, Industrial, Commercial, Agricultural, Residential, and Roadside, at the surface level and 30 cm depth. Detection was done by measuring the intensity of the C/H …

Gc-Ms Profiling And Antibacterial Activity Of Cold-Macerated Garlic Extracts Against Multidrug-Resistant Uropathogens, Fatima A. Khalaf, Saeed A. Fayadh

Karbala International Journal of Modern Science

The growing number of cases of multidrug-resistant (MDR) urinary tract infections has made the clinical management of urinary tract diseases a significant challenge; therefore, the need for effective adjunctive therapies cannot be overemphasized. This study evaluated the bioactive components and antibacterial efficacy of cold-macerated garlic extracts obtained using distilled water, 70% ethanol and hexane solvents against antimicrobial-resistant urinary isolates. Out of 250 urine samples that were analyzed, 124 (49.6%) showed significant microbial growth, with Escherichia coli being the most frequently isolated organism. The results of the phytochemical screening and Gas Chromatography-Mass Spectrometry (GC-MS) analysis showed that the ethanolic extract had …

Ultrafast Spectroscopy Of Organic Materials In Strong Light–Matter Interaction And Terahertz Optics, Kamyar Rashidi

Dissertations, Theses, and Capstone Projects

Ultrafast spectroscopy is a powerful tool for investigating phenomena that occur on extremely short timescales and for probing ultrabroadband spectral responses enabled by its ultrashort laser pulses. These capabilities are essential for advancing both the fundamental understanding of light–matter interactions and the development of next-generation optoelectronic technologies. The first part of this thesis investigates the ultrafast dynamics of organic exciton–polaritons and their application to controlling molecular excited-state processes using momentum-resolved pump–probe spectroscopy. A major challenge in these systems is the dark-state problem, where photoexcitation predominantly populates long-lived excitonic reservoir states that obscure the in trinsic dynamics of the hybrid light–matter …

Mesoscopic Scaling Of Microwave Transmittance And Disorder-Induced Alignment, Israel Kurtz

Dissertations, Theses, and Capstone Projects

This thesis presents microwave measurements and numerical simulations of wave propagation and transmission through random mesoscopic waveguides. We analyze the scaling of mesoscopic microwave conductance, including departures from Ohm’s law near channel openings, which are frequencies at which new propagating modes enter the system, and the evolution of modal phase alignment within the medium, which leads to the observed diversity of transmission eigenvalues. We extend the transmission matrix formalism to all sample depths using the flux matrix, which relates the flux amplitude within the sample to the incident flux, and decompose the flux at each sample depth into forward- and …

Potential Energy Landscape Formalism For Quantum Liquids, Yang Zhou

Dissertations, Theses, and Capstone Projects

Atomic delocalization due to nuclear quantum effects (NQE) remains poorly understood in low-temperature liquids near the glass state and during vitrification. Many liquids can be described accurately by treating their nuclei as classical particles, but this approximation fails for light elements such as He and H₂, small hydrogen-containing molecules such as water, and systems in which zero-point motion or isotope-substitution effects are important. Developing a general thermodynamic and statistical-mechanical description of such liquids has been challenging. This dissertation extends the potential energy landscape (PEL) formalism, originally developed for classical liquids and glasses, to liquids that obey quantum mechanics and exhibit …

Karhunen-Loève Modes For Coherent Arrays, Jack E. Mccrae, Santasri R. Bose-Pillai, Steven T. Fiorino

Faculty Publications

The optimal modes for correcting atmospheric turbulence on coherent arrays are determined. These Karhunen-Loève modes are eigenvectors of a covariance matrix. Creating this covariance matrix requires knowledge of the power spectrum of the turbulence, the aperture geometry, and a basis set for the matrix. The Kolmogorov power law is ordinarily chosen here for the turbulence spectrum. By choosing the phase on each array subaperture element minus the phase averaged over all subapertures as this basis, infinite values in the variances and covariances can be avoided. The piston mode of the whole array, which would otherwise also be infinite, is thus …

Dynamics Of Swimming Microorganisms At Structured Liquid Crystal Interfaces, Vajra Sabhapathy Badha

Graduate Doctoral Dissertations

Active matter systems are self-driven units that consume energy to generate motion and mechanical stresses, producing non-equilibrium states of broad physical significance. Examples include synthetic microswimmers and migrating cells. Motile bacteria are a widely studied biological example because their self-propelled motion, hydrodynamic interactions, and collective organization are strongly coupled to local environmental conditions. Their swimming is sensitive to interfacial viscoelasticity, ordering, confinement, and hydrodynamic boundary effects, making them useful for investigating how interfaces regulate active biological motion. Because bacterial accumulation and attachment at interfaces are central to colonization and biofilm formation, these interactions are relevant to both active matter physics …