Digital Commons Network^™

Approximating Data-Driven Combinatorial Search In The Feature Space: Pwfs, Mehmet Bugrahan Ayanoglu

USF Tampa Graduate Theses and Dissertations

This dissertation presents the development and application of a novel feature selection method, Probability Weighted Feature Selection (PWFS), designed to address key challenges in machine learning involving high-dimensional, noisy, or biased datasets. It is a comprehensive exploration of feature selection strategies to enhance the performance, interpretability, and practicality of machine learning models in both engineering systems and educational data mining. PWFS introduces a structured, probabilistic approach to feature selection that adaptively weights features based on their empirical contribution to model performance. This method not only accelerates convergence to near-optimal feature subsets but also enhances flexibility for ensemble learning by encouraging …

The Rise Of Foss In India: Empirical Evidence And Insights From Cross-Sectoral Case Studies, Arul George Scaria, Suryaprakash Mishra, Shubham Shinde, Rashi Singhal

Research Reports

The report analyses the adoption of FOSS in India, primarily through case studies across four sectors (healthcare, education, finance, and software and IT services) and different types of organisations (start-ups, non-profits, medium, large, and public sector organisations). The study highlights both the benefits and challenges experienced by organisations using FOSS. The study illustrates that while organisations benefit from increased innovations, cost/ time savings, flexibility, and enhanced security, they also face challenges such as lack of enough skilled personnel and limited community support. Organisations are also seen taking a cautious approach to licensing, favouring permissive licenses over restrictive ones. Based on …

In The Shadow Of Prompts: Adversarial Attacks And Model Cloning In Large Language Models, Kanchon Gharami

Doctoral Dissertations and Master's Theses

Large-language models (LLMs) already power mission critical tasks such as command-and-control chat, satellite ground-station automation, military analytics, and cyber-defense. Since most of these services are offered through application programming interfaces (APIs) that still expose full or top-k logits and lack mature safeguards, they present a serious, often overlooked attack surface. Earlier work has shown how to rebuild the output projection layer or distill surface behavior, but no attack has produced a deployable clone within a tight query budget. In this thesis, we address this problem by presenting a practical pipeline for cloning LLMs under constrained settings. The approach first estimates …

Unified Hybrid Censoring Samples From Power Pratibha Distribution And Its Applications, Mahmoud Mansour, Hebatalla H. Mohammad Dr, Khalaf S. Sultan Prof.

Basic Science Engineering

This paper suggests an extensive inferential method for the Power Pratibha Distribution (PPD) under Unified Hybrid Censoring Schemes (UHCSs), since there is a growing interest in flexible models in both reliability and service operations. This work studies the PPD model using standard Maximum Likelihood Estimation methods and modern Bayesian approaches too. Using a complex architecture, UHCS simulates tests more closely to what is done in practice than by using more basic censoring schemes. Using analysis, the probability and statistical ranges are carefully calculated for the parameters. Tests demonstrate that Bayesian estimation gives better results than many other methods for estimation, …

Non-Invasive Near-Field Microwave Sensors For Industrial Internet Of Things Applications, Abirami K

Theses and Dissertations

The industrial sector has been revolutionized by Industrial Revolution 4.0 with the advent of the Internet of Things (IoT) which integrates the physical environment using smart sensors and Artificial Intelligence (AI) mechanisms. This demands the design of smart sensors and actuators to improve the quality of services in Industrial IoT (IIoT). The sensor design using the microwave resonating principle has attracted the research and industrial community for portable, non-invasive, non-destructive and hygienic means to evaluate the quality of substances in the food and farming industry. The microwave planar sensor has advantages in terms of low footprint, low cost, and ease …

Studying Effect Of Temperature On Photovoltaic Characteristics Of Photovoltaic Modules Based On Cigs Solar Cells, Farrux Anvar O‘G‘Li Akbarov, Anvar Akbarovich Alimov

Technical science and innovation

The article presents the experimental results of the temperature dependence of the load current-voltage characteristics of a solar photovoltaic (PV) module based on a polycrystalline semiconductor binary compound Cu(In,Ga)Se₂ under normal sunlight P_rad=800±5 W/m², in a temperature range of (32÷60) ^оС. It was found that the temperature dependence of the photocurrent has two slopes, which is explained by a change in the generation-recombination mechanism. An increase in the short-circuit current with an increase in the temperature of the photovoltaic module is explained by an increase in the drift length of minority charge carriers, due …

Algorithms For Combined Regular Synthesis Of Controller Parameters In Control Systems For Dynamic Objects, Khusan Zakirovich Igamberdiev, Latafat Abbas Gizi Gardashova, Yulduz Mukhtarkhodjayevna Abdurakhmanova, Uktam Farkhodovich Mamirov

Technical science and innovation

Nonlinear control system that includes m-dimensional input control signal and extended (n+s) - dimensional state vector, the last s components of which form a vector of unknown parameters θ satisfying a general difference equation is being considered. The quality criterion is determined by the loss function. The optimal control must satisfy the Bellman equation with respect to the optimal loss function. To be defined an approximate solution that preserves an active use of information. For this purpose, the system is linearized in accordance to the nominal trajectory. This problem is seen as incorrectly stated. The values of the preliminary data …

Chromatography In Analysis And Quality Control Of Oil And Gas Products: Modern Approaches And Prospects, Muborak Akramovna Mirshomilova, Natalia Evgenievna Sheina, Lala Bekirova

Technical science and innovation

Chromatography plays a key role in the analysis and quality control of oil and gas products. Modern chromatographic methods, including gas and liquid chromatography, provide high accuracy, sensitivity and speed of analysis. They allow you to identify impurities, control the composition and compliance of products with standards. The article considers innovative approaches, such as multidimensional chromatography and the use of automated systems. Development prospects are discussed, including integration with AI and digital technologies, which opens up new opportunities to improve the efficiency of quality control in the oil and gas industry. This article considers the role of chromatographic methods in …

Technical And Economic Justification Of The New Design Of A Hydro-Accumulation Syste, Kurbon Salikhdjanovich Dzhuraev, Abdurasul Sayfutdinov, Elyor Doniyorovich Ismoilov

Technical science and innovation

The effective utilization of renewable energy sources such as solar and wind requires reliable and efficient energy storage systems due to their irregular and intermittent supply. This paper presents a novel hydro-accumulation system that significantly reduces energy consumption by integrating hydraulic ram pumps instead of traditional electrically powered pumps. The proposed system operates in cascade mode, where the kinetic energy of water is used multiple times through a sequence of hydraulic rams to pump water from a lower reservoir back to the upper one. Each stage of the system reuses the outflow water of the previous ram, achieving up to …

Comparative Analysis Of Gas And Mechanical Emissions From Electric Cars And Internal Combustion Engine Vehicles, Bakhtiyor Akhmatjonovich Kosimov

Technical science and innovation

This article analyzes the environmental impact of modern cars, in particular the amount of harmful substances emitted into the environment by electric cars and internal combustion engine cars, and provides scientific information on the substances that are released from cars in the form of not only gaseous emissions, but also dust particles generated by the mechanical wear of the brake system and tires. At the same time, this article also takes a scientific approach to the wear rates of brake pads and tires, their impact on environmental safety, and the level of dispersion of the microdust generated. Comparative tables have …

Unveiling Degradation Patterns In Dye-Sensitized Solar Cells: A Machine Learning Perspective, Ahmed Alali, Mahmoud Ashraf, Ahmad Muhammad, Sameh O. Abdellatif

Electrical Engineering

This study examines the time-dependent degradation of dye-sensitized solar cells (DSSCs) by systematically investigating several critical parameters, including TiO2 thickness, porosity, dye concentration, and iodine-based electrolyte concentration. We developed a novel figure of merit (FOM) to quantify the degradation rates, utilizing a finite element model (FEM) in COMSOL to simulate performance over time. 400 DSSC samples were fabricated, resulting in a comprehensive dataset comprising over 228,000 data points derived from experimental results and simulations. The findings reveal that PCE declines significantly over time, with an average initial efficiency of 4.0% for the DSSCs, dropping to approximately 0.5% after 360 h. …

Investigating Vacuum Insulator Flashover Resistance Of Rexolite And Acrylic Before And After Applying Novel Insulator Cleaning Techniques, Ritin Joseph

Electrical and Computer Engineering ETDs

Pulsed power involves accumulating large amounts of electrical energy and releasing it instantaneously. Large pulsed power accelerators use a vacuum insulator stack to facilitate power transfer from the liquid to vacuum section. Limiting the probability of surface flashover in this setting to acceptable levels improves machine longevity and prevents energy loss. Post-shot debris deposition requires a refurbishment process to prevent deterioration of dielectric performance, though the current technique of hand-sanding is long, labor-intensive, and pose serious health hazards. I have collected flashover data on frustrum-shaped Acrylic and C-Lec Rexolite® (cross-linked polystyrene) samples using a 500-kV, 20-ns risetime pulsed power test …

3d Solid Models, Bradley M. Ratliff

Model Desert Terrain Monochromatic DoT Dataset

3D solid models for model vehicles, target panels, objects, and the desert terrain model in STL file format.

Ground Truth Images, Bradley M. Ratliff

Model Desert Terrain Monochromatic DoT Dataset

Laboratory and scenario ground truth images for the Model Desert Terrain Monochromatic DoT dataset.

Polarimetric Data: Scenario 01, Bradley M. Ratliff

Model Desert Terrain Monochromatic DoT Dataset

Polarimetric data Scenario 01 collected within the Automated Remote Sensing Solar Simulation Lab at the University of Dayton. The data were collected using a visible monochromatic division-of-time imaging polarimeter. The dataset is parameterized across different sensor, scene, and illumination geometries that mimic outdoor solar irradiance conditions.

Dataset Description, Bradley M. Ratliff

Model Desert Terrain Monochromatic DoT Dataset

Polarimetric dataset containing data collected within the Automated Remote Sensing Solar Simulation Lab at the University of Dayton. The data were collected using a visible monochromatic division-of-time imaging polarimeter. A model desert terrain model was constructed and imaged for eight different scenarios consisting of different model panel and vehicle targets. The dataset is parameterized across different sensor, scene, and illumination geometries that mimic outdoor solar irradiance conditions.

Enhancing Power System Operation: Hydrogen, Dc Transmission Systems, And Robust Optimization, Anping Zhou

Electrical Engineering Theses and Dissertations

The increasing penetration of renewable energy sources (RESs) has brought considerable economic and environmental benefits to power system operations. However, it also introduces several critical challenges that should be addressed to ensure system reliability and efficiency. First, from the generation side, energy curtailment remains a persistent issue due to the random and intermittent nature of RESs. Second, from the transmission side, delivering power from remote RESs (e.g., offshore wind farms) requires substantial infrastructure investment and careful planning. Third, from the operation side, the inherent uncertainty and variability of RES generation create operational difficulties that necessitate advanced mathematical optimization tools for …

Generalized Dynamic Pole Placement Control For Voltage Source Converters With Inductive-Capacitive Output Filters, Byunghee Moon

Theses and Dissertations

Voltage Source Converters (VSCs) with inductive-capacitive (LC) filters are prevalent in power electronics applications. There are many control techniques utilized for that category of power converter topology. However, as converter applications continue to increase their switching frequency, faster control methods are desirable to take advantage of the higher bandwidth that increased switching frequency allows for

Dynamic pole placement (DPP) controls are very promising methods for achieving high-speed control of VSCs with LC filters. However, the conventional DPP controls have very high sensitivity to disturbances and noise. In order to address this, two novel DPP current control methods are proposed and …

Addressing Key Challenges In Mhz Power Converters, Aqarib Hussain

Theses and Dissertations

Power electronics are essential in applications such as aerospace, electric vehicles, and electric ships where compact, efficient, and high power-density converters are increasingly demanded. This push toward miniaturization has led to converter designs operating at switching frequencies in the megahertz (MHz) range. Higher-frequency operation enables significant reductions in passive component sizes—particularly transformers and inductors—thereby facilitating dense packaging. However, these benefits come with new challenges, including increased thermal stress, complex semiconductor behavior, higher-frequency magnetic design constraints, and elevated electromagnetic interference (EMI).

This research addresses several key challenges in MHz converter design. The first part involves the development of a 1-MHz, 1-kW …

Sidesense: Robust Physiological Motion Detection Via Mmwave Joint Communication And Sensing Systems With Multiple Beams, Mohammed Shadman Ishrak, Jannatun Noor Sameera, Alvin Yang, Yanjun Pan, Yao Zheng, Olga Boric-Lubecke, Victor M. Lubecke

Electrical Engineering and Computer Science Faculty Publications and Presentations

A 28-GHz multibeam joint communication and sensing system called SideSense is presented, in which a line-of-sight (LoS) beam is used to maintain reliable communication, while other sensing beams are used to enhance physiological motion detection. SideSense decodes the motion frequency and shape from the channel state information (CSI) by first tuning the gain ratio and phase differences between the LoS communication beam and non-LoS (NLoS) beam to maximize the sensing signal-to-noise ratio (SSNR) without significantly degrading the communication channel capacity (CCC). Analytical results based on a bistatic model are presented to show a gain ratio of around 1 and a …

Statistical Monitoring Of Hard Faults In Digital Systems, Dany Akshay Deep Isukapalli

Electrical Engineering Theses and Dissertations

Achieving a high test coverage is crucial for helping to ensure that integrated circuits are working correctly and are non-defective. Although scan-based structural tests are used throughout the industry, high-level functional tests may be needed to detect some defects— especially those that are environmentally sensitive. Unfortunately, the character of functional test makes it difficult to obtain high coverage, and it is even hard to estimate coverage because fault simulation times of large circuits are long. As a result, some method is required for predicting the ability of a functional test that has not been fault simulated to detect defects. In …

Data Annotations, Bradley M. Ratliff

Model Desert Terrain Monochromatic DoT Dataset

Pixel-wise object masks for each polarimetric scene in ASL file format for the Model Desert Terrain Monochromatic DoT data.

Decentralised Consensus Control Of Hybrid Synchronous Condenser And Grid-Forming Inverter Systems In Renewable-Dominated Low-Inertia Grids, Hamid Soleimani, Asma Aziz, S. M.Muslem Uddin, Mehrdad Ghahramani, Daryoush Habibi

Research outputs 2022 to 2026

The increasing penetration of renewable energy sources (RESs) has significantly altered the operational characteristics of modern power systems, resulting in reduced system inertia and fault current capacity. These developments introduce new challenges for maintaining frequency and voltage stability, particularly in low-inertia grids that are dominated by inverter-based resources (IBRs). This paper presents a hierarchical control framework that integrates synchronous condensers (SCs) and grid-forming (GFM) inverters through a leader–follower consensus control architecture to address these issues. In this approach, selected GFMs act as leaders to restore nominal voltage and frequency, while follower GFMs and SCs collaboratively share active and reactive power. …

Analysis Of Vision Transformers And Domain Adaptation In Long-Range Facial Recognition, Zachary Michael Swanson

Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research

Atmospheric turbulence presents a significant barrier to long-range facial recognition, introducing severe geometric distortions and blur that degrade image quality. This thesis investigates deep learning approaches for mitigating these effects, with a focus on transformer based architectures and domain adaptation strategies.

An in-depth benchmarking study was performed using convolutional neural networks (CNNs) and vision transformers (ViTs) on the Husker BRIAR Research Collection from up to 500m (HBRC-500) face dataset. The results demonstrated that vision transformers, particularly hierarchical vision transformers like the shifted-window (Swin) transformer, outperform CNN-based models at long distances due to their ability to model global spatial relationships and …

Optical And Thermal Characterization Of Vertically Conducting Β-Ga₂O₃ Diodes Grown On 4h-Sic Substrates For Short-Wavelength (<254 Nm) Detection, Muhammad Hassan Tahir

Theses and Dissertations

The advancement of compact, thermally stable, and efficient devices for deepultraviolet (DUV) detection below 254 nm is critical for solar-blind sensing, radiation monitoring, and high-power electronics. This thesis presents the growth, fabrication, and detailed optical and thermal characterization of vertically conducting β-gallium oxide (βGa₂O₃) Schottky barrier diodes (SBDs) grown on n-type 4H-Silicon Carbide (4H-SiC) substrates using metal-organic chemical vapor deposition (MOCVD).

β-Ga₂O₃ is an ultra-wide bandgap (UWBG) semiconductor (~4.8 eV) with intrinsic DUV transparency and high breakdown electric field, making it an ideal candidate for short-wavelength photodetection. However, its low thermal conductivity limits its vertical device performance. To overcome this, …

Effect Of Growth Conditions On The Performance Of Vertically Conducting Beta-Ga2o3 Diodes On 4h-Sic Substrate By Mocvd, Nifat Jahan Nipa

Theses and Dissertations

This thesis highlights the critical influence of doping strategies, specifically co-delta doping with silicon (Si) and indium (In), on improving the structural quality and device performance of β-Ga₂O₃-based Schottky barrier diodes (SBDs). To achieve better thermal management, β-Ga₂O₃ thin film was grown on bulk 4H-SiC substrates using the Metal-Organic Chemical Vapor Deposition (MOCVD) technique, renowned for its precise control over composition, thickness and doping profile. The ultra-wide bandgap (UWBG), high critical breakdown field and low turn-on resistance of β-Ga₂O₃ make it a strong candidate for next-generation power electronics and short-wavelength detection in extreme environments. However, the presence of structural defects …

Optimal Placement Of Distributed Generation Units In Power Distribution Networks Using Particle Swarm Optimization, Owdean M. Suwi

Tanzania Journal of Engineering and Technology (TJET)

Power losses and voltage drops in distribution networks are critical issues in power system operation, reducing efficiency, reliability, and overall quality of the power supply to customers. Additionally, the rising electricity demand, deregulation of energy markets, and congestion in transmission networks have further contributed to the declining performance of the grid. To address these challenges, integrating distributed generation units (DGUs) into electric distribution systems has gained significant attention. Furthermore, the integration of DGUs into conventional fossil fuel-based power plants is becoming necessary to reduce greenhouse gas emissions. However, proper placement and sizing of DGUs are crucial for achieving optimal benefits. …

A Smart System For Detecting Anatomic And Histological Symptoms Of Diseased Agricultural Plants, Rustam Baratov, Himola Sunnatillayeva, Alimardon Mamatovich Mustafoqulov

Chemical Technology, Control and Management

This study describes a novel agricultural plant disease detecting smart system, capable of handling measured plant body parameters and images received by high resolution camera at the same time. The proposed plant disease detection method is based on evaluation of the signals received by measured and controlled plant body physical parameters like resistance, temperature and capacitance of the plant stem and image processing. An analogue plant model based on an electrical circuit with distributed parameters was developed. In addition, in the article the block diagram of the smart system for the early detection of plant diseases, the circuit diagram, its …

Prospects Of Clean Cooking Energy In Africa - Transition Pathways And Implications, Joseph H. Kihedu Dr.

Tanzania Journal of Engineering and Technology (TJET)

Despite abundant renewable energy resources, African countries still suffer from energy poverty, particularly in cooking. Up to 2022, about 74% of the African population had no access to clean cooking energy. With focus to Sub-Saharan African population, 90% has no access to clean cooking energy which decrease by 7% when kerosene is included. Traditional cooking, which involves the use of charcoal and firewood, is associated with health problems, environmental degradation, socioeconomic issues, and gender inequality. Transitioning to clean cooking energy not only promises significant health benefits but also offers opportunities for sustainable economic development and environmental preservation. In this study, …

Development And Experimental Validation Of A Non-Invasive Blood Group Detection System, Nurath K. Nurudini

Tanzania Journal of Engineering and Technology (TJET)

An individual's blood group consists of red blood cell antigens whose composition is determined by protein presence, antigen structure, and gene series. Persons aged above six months have significant anti-A and/or anti-B in their serum. During transplantation and transfusion, ABO blood group identification is the most essential factor. The conventional method involves drawing blood samples from patients, and the blood group is determined based on the antigen-antibody reaction. This method consists of adding chemical reagents. However, this requires time of operation, and throughput analysis is high, and the process is also challenging to interpret. Accurate and rapid identification of blood …