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Optimal Control Of Ion Exchange Process For Chromate Removal And Protein A Chromatography For Antibody Extraction, Fadi Ghanem Dec 2023

Optimal Control Of Ion Exchange Process For Chromate Removal And Protein A Chromatography For Antibody Extraction, Fadi Ghanem

Theses and Dissertations

Ion exchange resins are widely used in the extraction of hazardous chemicals as well as the recovery of precious molecules. Therefore, an early breakthrough from the resin system can lead to toxic compounds affecting the drinking water quality or inefficient use of costly resins. Hence, accurate modeling of the ion exchange process and control strategy can enable decisions that assist in avoiding leakage when facing fluctuations in the inlet contaminant concentrations. In this work, the ion exchange process is modeled via the method of moments where the system uncertainties are captured via stochastic modeling using Ito processes. The flow rate …


Paper-Based Ratiometric Sensor Array For Pathogenic Bacterial Species Identification, Aayushi Laliwala Dec 2023

Paper-Based Ratiometric Sensor Array For Pathogenic Bacterial Species Identification, Aayushi Laliwala

Theses & Dissertations

Bacterial infections are the leading cause of mortality worldwide due to the lack of accurate diagnosis of the pathogens causing infections. Currently, microbiological and molecular techniques are used to identify pathogenic bacteria. However, these techniques have limitations as they are time-consuming, cost-inefficient, and require trained personnel. Therefore, timely and precise identification of pathogenic bacteria is crucial for public safety. Our lab previously synthesized a fluorescent sensor array (3-hydroxyflavone derivatives) encapsulated in hyaluronic acid-based nanoparticles to identify bacterial species and recognize their Gram status. Though promising, this technique was relatively time-consuming and required high sample and volumes.

To overcome these limitations, …


Solar-Powered Microgrids In Northern California: An Opportunity For Resilience, Marina Riddle Dec 2023

Solar-Powered Microgrids In Northern California: An Opportunity For Resilience, Marina Riddle

Master's Projects and Capstones

Planned and unplanned power outages have been increasing in frequency and duration, negatively impacting all public sectors, and threatening public safety. These outages are deadly to those who rely on medical devices. As climate change-fueled extreme weather events (wildfires, earthquakes, storms, etc.) also increase in frequency, our electrical grid must be prepared to bounce back. Microgrids provide necessary redundancy and reliability. Through a novel GIS suitability analysis, based on solar radiation, land use type, local energy demand, distance to transmission lines, distance to roads, and slope, optimal locations for solar-powered microgrids throughout Northern California were determined. The counties of Fresno, …


Fabrication And Characterization Of Flexible Microelectrode Arrays On Kapton Polyimide For Implantable Spinal Cord Stimulation Applications, Nabil Jamhour Dec 2023

Fabrication And Characterization Of Flexible Microelectrode Arrays On Kapton Polyimide For Implantable Spinal Cord Stimulation Applications, Nabil Jamhour

Theses and Dissertations

Recent advances in spinal cord stimulation (SCS) technology have made a significant impact in the treatment of chronic pain which is a prevalent issue amongst 20% of the population in developed nations. A few medical device manufactures have developed SCS devices that have been studied in clinical environments and reported to be effective and safe for commercial use. However, the current SCS devices available are bulky, rigid, and still present infection, fibrosis, discomfort, pulse delivery challenges and other concerns for patients. In this study, flexible electrodes processed on Kapton® polyimide films by physical vapor and inkjet deposition are fabricated and …


Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump Dec 2023

Air-Jet Bioprinting Of Stem Cell-Encapsulated Alginate Micro-Droplets For Organoid Biomanufacturing, Mirabella B. Stump

Electronic Theses and Dissertations

Biomanufactured 3D-organoids show promise for modeling and treating various conditions, particularly insulin-dependent diabetes mellitus (type-1 diabetes). Pancreatic islet organoids serve as sustainable sources of insulin-producing β-cells, potentially restoring insulin regulation in patients and providing a long-term solution for diabetes. Hydrogel droplet printing is an emerging technique in regenerative medicine due to its advantageous tunability and biocompatibility; however, challenges of consistency, quality control, and scalability persist. To address these issues, we developed a novel air-jetting based droplet bioprinting system for the generation of monodispersed alginate micro-droplets. The objective of this project was to incorporate human induced pluripotent stem cells (hiPSCs) into …


Monitoring Time Domain Characteristics Of Parkinson's Disease Using 3d Memristive Neuromorphic System, Md Abu Bakr Siddique, Yan Zhang, Hongyu An Dec 2023

Monitoring Time Domain Characteristics Of Parkinson's Disease Using 3d Memristive Neuromorphic System, Md Abu Bakr Siddique, Yan Zhang, Hongyu An

Michigan Tech Publications

INTRODUCTION: Parkinson's disease (PD) is a neurodegenerative disorder affecting millions of patients. Closed-Loop Deep Brain Stimulation (CL-DBS) is a therapy that can alleviate the symptoms of PD. The CL-DBS system consists of an electrode sending electrical stimulation signals to a specific region of the brain and a battery-powered stimulator implanted in the chest. The electrical stimuli in CL-DBS systems need to be adjusted in real-time in accordance with the state of PD symptoms. Therefore, fast and precise monitoring of PD symptoms is a critical function for CL-DBS systems. However, the current CL-DBS techniques suffer from high computational demands for real-time …


Microplate-Like Metal Pyrophosphate Engineered On Ni-Foam Towards Multifunctional Electrode Material For Energy Conversion And Storage, Rishabh Srivastava Dec 2023

Microplate-Like Metal Pyrophosphate Engineered On Ni-Foam Towards Multifunctional Electrode Material For Energy Conversion And Storage, Rishabh Srivastava

Electronic Theses & Dissertations

High clean energy demand, dire need for sustainable development, and low carbon footprints are the few intuitive challenges, leading researchers to aim for research and development for high-performance energy devices. The development of materials used in energy devices is currently focused on enhancing the performance, electronic properties, and durability of devices. Tunning the attributes of transition metals using pyrophosphate (P2O7) ligand moieties can be a promising approach to meet the requirements of energy devices such as water electrolyzers and supercapacitors, although such a material’s configuration is rarely exposed for this purpose of study.

Herein, we grow …


Verification And Validation Of Robot Manipulator Adaptive Control With Actuator Deficiency, Sebastian Comeaux Dec 2023

Verification And Validation Of Robot Manipulator Adaptive Control With Actuator Deficiency, Sebastian Comeaux

Doctoral Dissertations and Master's Theses

This work addresses the joint tracking problem of robotic manipulators with uncertain dynamical parameters and actuator deficiencies, in the form of an uncertain control effectiveness matrix, through adaptive control design, simulation, and experimentation. Specifically, two novel adaptive controller formulations are implemented and tested via simulation and experimentation. The proposed adaptive control formulations are designed to compensate for uncertainties in the dynamical system parameters as well as uncertainties in the control effectiveness matrix that pre-multiplies the control input. The uncertainty compensation of the dynamical parameters is achieved via the use of the desired model compensation–based adaptation, while the uncertainties related to …


Deep-Learning Based Multiple-Model Bayesian Architecture For Spacecraft Fault Estimation, Rocio Jado Puente Dec 2023

Deep-Learning Based Multiple-Model Bayesian Architecture For Spacecraft Fault Estimation, Rocio Jado Puente

Doctoral Dissertations and Master's Theses

This thesis presents recent findings regarding the performance of an intelligent architecture designed for spacecraft fault estimation. The approach incorporates a collection of systematically organized autoencoders within a Bayesian framework, enabling early detection and classification of various spacecraft faults such as reaction-wheel damage, sensor faults, and power system degradation.

To assess the effectiveness of this architecture, a range of performance metrics is employed. Through extensive numerical simulations and in-lab experimental testing utilizing a dedicated spacecraft testbed, the capabilities and accuracy of the proposed intelligent architecture are analyzed. These evaluations provide valuable insights into the architecture's ability to detect and classify …


Dam Failure And Incident Investigations, Nathaniel Gee Dec 2023

Dam Failure And Incident Investigations, Nathaniel Gee

Theses and Dissertations

There are multiple dam failures and dam safety incidents every year in the United States. There are currently no standard policy requirements for when or how to conduct failure or incident investigations. This paper first reviews one of the most significant failures in US history, the failure of Buffalo Creek Dam No. 3 in order to explore the impacts of one significant failure on dam safety policy in the US. The paper then explores the currents state of the industry by reviewing 58 different dam failure or incident investigation reports based on incidents that occurred in the United States from …


Survey Of Transfer Learning Approaches In The Machine Learning Of Digital Health Sensing Data, Lina Chato, Emma Regentova Dec 2023

Survey Of Transfer Learning Approaches In The Machine Learning Of Digital Health Sensing Data, Lina Chato, Emma Regentova

Electrical & Computer Engineering Faculty Research

Machine learning and digital health sensing data have led to numerous research achievements aimed at improving digital health technology. However, using machine learning in digital health poses challenges related to data availability, such as incomplete, unstructured, and fragmented data, as well as issues related to data privacy, security, and data format standardization. Furthermore, there is a risk of bias and discrimination in machine learning models. Thus, developing an accurate prediction model from scratch can be an expensive and complicated task that often requires extensive experiments and complex computations. Transfer learning methods have emerged as a feasible solution to address these …


Impact Of Methylene Blue On Enhancing The Hydrocarbon Potential Of Early Cambrian Khewra Sandstone Formation From The Potwar Basin, Pakistan, Muhammad Ali, Abdul M. Shar, Nurudeen Yekeen, Hussein Abid, Muhammad S. Kamal, Hussein Hoteit Dec 2023

Impact Of Methylene Blue On Enhancing The Hydrocarbon Potential Of Early Cambrian Khewra Sandstone Formation From The Potwar Basin, Pakistan, Muhammad Ali, Abdul M. Shar, Nurudeen Yekeen, Hussein Abid, Muhammad S. Kamal, Hussein Hoteit

Research outputs 2022 to 2026

Significant amounts of hydrocarbon resources are left behind after primary and secondary recovery processes, necessitating the application of enhanced oil recovery (EOR) techniques for improving the recovery of trapped oil from subsurface formations. In this respect, the wettability of the rock is crucial in assessing the recovery and sweep efficiency of trapped oil. The subsurface reservoirs are inherently contaminated with organic acids, which renders them hydrophobic. Recent research has revealed the significant impacts of nanofluids, surfactants, and methyl orange on altering the wettability of organic-acid-contaminated subsurface formations into the water-wet state. This suggests that the toxic dye methylene blue (MB), …


12.04.2023 Orsp Connect, Liz Williamson Dec 2023

12.04.2023 Orsp Connect, Liz Williamson

ORED Newsletter

Week of December 4, 2023


Guidelines For Sustainable Use Of Mobile Instant Messaging Apps In Higher Education: A South African Case Study, Bronwyn C. Swartz, Sweta Patnaik Dec 2023

Guidelines For Sustainable Use Of Mobile Instant Messaging Apps In Higher Education: A South African Case Study, Bronwyn C. Swartz, Sweta Patnaik

Higher Learning Research Communications

Objective: The purpose of the study was to propose guidelines to facilitate the sustainable and successful use of mobile instant messaging apps for learning and teaching based on a review of the literature and perceptions of educators. Fraser’s model of redistribution, recognition, and representation served as the theoretical framework. This study provides a mechanism for the development of a socially just and inclusive online classroom environment.

Method: We conducted two focus groups (n = 4 and n = 3) in November 2021 at a university of technology in South Africa to explore the perceptions of educators on using mobile …


Residential Indoor Air Quality Study – Assessment And Mitigation, Giovanni Cerrato Dec 2023

Residential Indoor Air Quality Study – Assessment And Mitigation, Giovanni Cerrato

Mechanical Engineering Theses

An increased awareness in residential indoor air quality (IAQ) has led to an increase in technologies that assist in improving IAQ. Two such technologies include Electro-static (ES) air cleaners and Photocatalytic Oxidizing (PCO) air cleaners. ES air cleaners remove particulate matter from indoor air, but are known to emit ozone, a contaminant, as a by-product. PCO air cleaners abate gaseous pollutants (i.e., Volatile Organic Compounds, VOCs); however, a lack of testing standards creates confusion about their effectiveness in improving IAQ in a real residential home. On the other hand, environmental variables such as temperature and humidity were found to affect …


12.11.2023 Orsp Connect, Liz Williamson Dec 2023

12.11.2023 Orsp Connect, Liz Williamson

ORED Newsletter

December 11, 2023 Newsletter


Clean Energy & Sustainable Environment By Carbon Dioxide Mitigation Strategies, Md Fahim Shahriar Dec 2023

Clean Energy & Sustainable Environment By Carbon Dioxide Mitigation Strategies, Md Fahim Shahriar

Mechanical Engineering Theses

Dissolution trapping is one of the most dominant mechanisms for secure storage of CO2 injected in porous subsurface formations saturated with brine. This study uses a 2D visual Hele-Shaw cell to investigate and visualize the impact of CO2 injection locations, reservoir dipping angle, permeability heterogeneity, and brine with different initial ionic concentrations on the density-driven convection during CO2 dissolution (Chapter 2). Also, the role of complex heterogeneity, i.e., irregular permeability distribution in CO2 dissolution, is investigated using a novel experimental approach to create medium permeability heterogeneity in Hele-Shaw cells (Chapter 3). We observed that the presence …


Biophysical Study Of The Von Willebrand Factor Via Optical Tweezers—Investigating The Collagen Binding Force Profile To Distinguish Types Of Von Willebrand Disease, Leigh Hardin Dec 2023

Biophysical Study Of The Von Willebrand Factor Via Optical Tweezers—Investigating The Collagen Binding Force Profile To Distinguish Types Of Von Willebrand Disease, Leigh Hardin

Honors Theses

von Willebrand disease (vWD) is a genetic disorder due to quantitative or qualitative abnormalities of the von Willebrand factor (vWF). There are three main types of vWD in addition to acquired von Willebrand syndrome. Type 1 is due to a deficiency of vWF, while Type 3 is due to a complete absence of vWF. Type 2 is due to malformed factors and broken into four subtypes: 2A, 2B, 2M, and 2N. Each subtype corresponds to different abnormalities of the protein that affect its binding to other proteins such as collagen, Factor VIII, platelets, etc. Therefore, determining a patient’s type and …


Chronic Kidney Disease Android Application, Paul Le Dec 2023

Chronic Kidney Disease Android Application, Paul Le

Computer Science and Engineering Senior Theses

Chronic kidney disease is increasingly recognized as a leading public health problem over the world that affects more than 10 percent of the population worldwide, where electrolytes and wastes can build up in your system. Kidney failure might not be noticeable until more advanced stages where it may then become fatal if not for artificial filtering or a transplant. As a result, it is important to detect kidney disease early on to prevent it from progressing to kidney failure. The current main test of the disease is a blood test that measures the levels of a waste product called creatine …


A Tunable System For High Frequency Bioimpedance Plethysmography, Daniel H. Tebbs Dec 2023

A Tunable System For High Frequency Bioimpedance Plethysmography, Daniel H. Tebbs

Theses and Dissertations

Bioimpedance measurements are useful for determining a variety of biological conditions. By accounting for small impedance variations due to the arterial pulse, the effect of the blood can be studied more closely. The quasi-circulator system presented enables monitoring of pulsatile impedance changes with input frequencies above 1 MHz. The adjustable Rmatch allows for dynamic tuning of the system to increase sensitivity. By tuning Rmatch to be near the match point, the pulsatile signal in the output magnitude can be amplified, and tuning Rmatch to be at the match point causes the pulsatile signal in the output phase to be amplified. …


Dynamic Segmental Kinematics Of The Lumbar Spine During Diagnostic Movements, Paul Mcmullin Dec 2023

Dynamic Segmental Kinematics Of The Lumbar Spine During Diagnostic Movements, Paul Mcmullin

Theses and Dissertations

While lumbar kinematics can be measured in vivo, most measurements are invasive (such as percutaneous bone pins), provide high doses of radiation (such as biplane fluoroscopy), or are taken with the patient in a static position (such as MRIs). Recent work suggests that lumbar kinematics can be determined by dynamic measurements of epidermal strain in the lower back. This work aims to develop and examine a method of examining lumbar kinematics via optoelectronic motion capture utilizing skin-mounted markers in the lumbar region. Two studies were performed. One study examined lumbar epidermal strain in 28 asymptomatic subjects during diagnostic movements, while …


Ncmpy: A Modelling Software For Neutrosophic Cognitive Maps Based On Python Package, Ilanthenral Kandasamy, Divakar Arumugam, Aryan Rathore, Ateeth Arun, Manan Jain, Vasantha .W.B, Florentin Smarandache Dec 2023

Ncmpy: A Modelling Software For Neutrosophic Cognitive Maps Based On Python Package, Ilanthenral Kandasamy, Divakar Arumugam, Aryan Rathore, Ateeth Arun, Manan Jain, Vasantha .W.B, Florentin Smarandache

Neutrosophic Systems with Applications

Cognitive maps are a vital tool that can be used for knowledge representation and reasoning. Fuzzy Cognitive Maps (FCMs) are popular soft computing techniques used to model large and complex systems, and they can aid in explainable artificial intelligence (AI). FCMs, however, cannot model the indeterminacy that arises in a system due to various uncertainties. Neutrosophic Cognitive Maps (NCMs), upgraded FCMs that could model indeterminacy, were introduced to address this issue. NCMs are a generalization of FCMs, a field of cognitive science firmly based on neural networks. NCMs have been used to solve a wide range of problems. NCMs were …


Investigation And Control Of Görtler Vortices In High-Speed Flows, Omar Es-Sahli Dec 2023

Investigation And Control Of Görtler Vortices In High-Speed Flows, Omar Es-Sahli

Theses and Dissertations

High-amplitude freestream turbulence and surface roughness elements can excite a laminar boundary-layer flow sufficiently enough to cause streamwise-oriented vortices to develop. These vortices resemble elongated streaks having alternate spanwise variations of the streamwise velocity. Following the transient growth phase, the fully developed vortex structures downstream undergo an inviscid secondary instability mechanism and, ultimately, transition to turbulence. This mechanism becomes much more complicated in high-speed boundary layer flows due to compressibility and thermal effects, which become more significant for higher Mach numbers. In this research, we formulate and test an optimal control algorithm to suppress the growth rate of the aforementioned …


Assessing The Relationship Between Soil Health/Quality And Water Quality In The Mississippi Delta, Laura Andrea Sarmiento Rodriguez Dec 2023

Assessing The Relationship Between Soil Health/Quality And Water Quality In The Mississippi Delta, Laura Andrea Sarmiento Rodriguez

Theses and Dissertations

Several studies have reported agronomic benefits by improving soil health/quality, but uncertain knowledge remains when determining specific impacts on water quality off-field. This study investigated the links between runoff water quality and soil health/quality in agricultural fields of the Mississippi delta under three land management scenarios: Conservation Reserve Program (CRP), vegetative buffer (VB), and row crops (RC). Using the Soil Management Assessment Framework (SMAF), a Soil Quality Index (SQI) was obtained based on ten soil health/quality indicators from 2008 and 2012 datasets. The SMAF identified significant differences in soil health/quality improvements among scenarios over a four-year period. Varied relationships between …


Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise Dec 2023

Development Of An Automated Delivery System To Apply Copper Sulfate Crystals Using Precision Dry Fertilizer Application Technology, Kevin Charles Wise

Theses and Dissertations

The digenetic trematode, Bolbophorus damnificus, poses a substantial threat to catfish aquaculture, causing significant economic losses. Infestations lead to suppressed feed consumption, secondary bacterial infections and poor production performance. Survey data reveals widespread infestation in the in the southeastern United States. Current control strategies involve the application of a concentrated copper sulfate solution to reduce snail populations which serve as the first intermediate host of the trematode life cycle. This study aimed to improve treatment efficacy by developing a granular copper sulfate application system. A modified Gandy fertilizer applicator, equipped with a programmable control system, demonstrated accurate distribution of copper …


Stream Water Quality Under Baseflow Conditions In A Livestock Production Area, Maryi Lorena Chavarro Chaux Dec 2023

Stream Water Quality Under Baseflow Conditions In A Livestock Production Area, Maryi Lorena Chavarro Chaux

Theses and Dissertations

This study evaluates the spatial and temporal impacts of implemented Best Management Practices (BMP) on stream water quality under baseflow conditions in a stream segment affected by livestock production. The BMPs includes 10-m fenced riparian zone and crossing paths along the reach segment. Grab water samples and water quality monitoring were collected biweekly from July 2019 to March 2022. Water quality parameters included temperature, dissolved oxygen, electric conductance, total dissolved solids, turbidity, and pH. Water samples were lab analyzed for sediments and nutrients. Results evidenced poor water quality before BMPs implementation, with nutrient concentrations exceeding the nation's and state's criteria. …


Network Layer Reliability And Security In Energy Harvesting Wireless Sensor Networks, Jing Yang Dec 2023

Network Layer Reliability And Security In Energy Harvesting Wireless Sensor Networks, Jing Yang

Theses and Dissertations

Wireless sensor networks (WSNs) have become pivotal in precision agriculture, environmental monitoring, and smart healthcare applications. However, the challenges of energy consumption and security, particularly concerning the reliance on large battery-operated nodes, pose significant hurdles for these networks. Energy-harvesting wireless sensor networks (EH-WSNs) emerged as a solution, enabling nodes to replenish energy from the environment remotely. Yet, the transition to EH-WSNs brought forth new obstacles in ensuring reliable and secure data transmission.

In our initial study, we tackled the intermittent connectivity issue prevalent in EH-WSNs due to the dynamic behavior of energy harvesting nodes. Rapid shifts between ON and OFF …


A Review On Ship Recycling Industry In Bangladesh From Global Perspective, Ahammad Abdullah, Zobair Ibn Awal, M Ziauddin Alamgir, Md. Jobayer Mia, Farihatul Mim, Utpal K. Dhar Dec 2023

A Review On Ship Recycling Industry In Bangladesh From Global Perspective, Ahammad Abdullah, Zobair Ibn Awal, M Ziauddin Alamgir, Md. Jobayer Mia, Farihatul Mim, Utpal K. Dhar

Journal of Ocean and Coastal Economics

At present, the global center of the ship breaking and recycling industry is in South Asia, specifically Bangladesh, India, and Pakistan. These three countries account for 70–80 percent of the international recycling market for ocean-going vessels, with China and Turkey covering most of the remaining market. Only about 5 percent of global volume is scrapped outside these five countries. Bangladesh has environmentally beneficial coastal region and affordable labor that make the shipbreaking and recycling business as a potential sector for the country. In addition, ship recycling and its related businesses are helping to solve our nation’s unemployment issues at all …


Timeseries Forecasting Of U.S. Housing Price Index Using Machine Learning And Deep Learning Models, Krishna Chaitanya Nunna Dec 2023

Timeseries Forecasting Of U.S. Housing Price Index Using Machine Learning And Deep Learning Models, Krishna Chaitanya Nunna

Dissertations

Time series forecasting is a promising technique for various applications which predicts future values or patterns by taking historical data as base. Forecasting future trends is very beneficial for different industries to make valuable decisions and strategies. One such industry is housing market; it has biggest influence on U.S. economy. Housing price index (HPI) is a one of the crucial economic indices published by various government funded and private agency to benefit several industries and individuals for better analysis of future trends of housing market.

Several factors influence the HPI, economical, geographical, and demographic features. Development of traditional time series …


Change In Air Cargo Revenue Before Vs During The Covid-19 Pandemic, Ali Abushal, Timothy R. Buchal, Ethan Noto, Brooke Wheeler, Vivek Sharma Dec 2023

Change In Air Cargo Revenue Before Vs During The Covid-19 Pandemic, Ali Abushal, Timothy R. Buchal, Ethan Noto, Brooke Wheeler, Vivek Sharma

Aeronautics Student Publications

This study aimed to investigate the changes in revenue experienced by cargo airlines before and during the COVID-19 pandemic. To gather the necessary data, information was sourced from the Securities and Exchange Commission's (SEC) databases and the websites of the specific airlines. The findings of this study revealed significant shifts in revenue for cargo airlines during the pandemic. Some airlines experienced an unexpected rise in revenue, challenging our previous understanding of the industry dynamics. These findings highlighted the importance of conducting a comprehensive analysis that includes a larger view of the aviation sector.

The COVID-19 pandemic had a profound impact …