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Comparison Of Conventional And Adaptive Acoustic Beamforming Algorithms Using A Tetrahedral Microphone Array In Noisy Environments, Megan Brittany Ewers

Dissertations and Theses

In situ acoustic measurements are often plagued by interfering sound sources that occur within the measurement environment. Both adaptive and conventional beamforming algorithms, when applied to the outputs of a microphone array arranged in a tetrahedral geometry, are able to capture sound sources in desired directions and reject sound from unwanted directions. Adaptive algorithms may be able to measure a desired sound source with greater spatial precision, but require more calculations and, therefore, computational power. A conventional frequency-domain phase-shift algorithm and a modified adaptive frequency-domain Minimum Variance Distortionless Response (MVDR) algorithm were applied to simulated and recorded signals from a …

Assessing The Performance Of Jatropha Curcas And Moringa Oleifera Conditioners Towards Improving Fecal Sludge Treatment For Agricultural Purpose, Doglas Benjamin1

Tanzania Journal of Engineering and Technology (TJET)

been proposed as alternative solutions to replace chemical conditioners for fecal sludge (FS) treatment. However, their effectiveness in treating FS for safe agricultural use has not been thoroughly evaluated. The aim of this study was to assess the suitability of FS treated with Moringa oleifera and Jatropha Curcas conditioners for agricultural use. Physicochemical parameters Indexes, salinity and sodium hazard levels (Wilcox Diagram analysis), and removal efficiency of nutrients and pathogens were evaluated. Qualitative experiments were conducted using dewatering treatment chambers containing untreated control FS samples, FS treated with Moringa oleifera and Jatropha Curcas conditioners at the University of Dar es …

Difficulties Of Hydrofracturing In Sandstone – Experimental Study, S Vikram, Dheeraj Kumar, Ds Subrahmanyam

Journal of Sustainable Mining

Hydrofracturing in sandstone is not an easy task. Sandstone is porous; fluid dissipation is common hence unable to obtain breakdown pressures in certain flow rates (0.0000005–0.0001 m3/s). The higher flow rate (0.00025 m3/s) is ascertained to determine the fracturing pressures. Due to this, fracture propagation and delineation are observed [1]. To enhance, an experimental method is adopted by carrying out 6 Hydrofracturing tests in a borehole comprising sandstone. A high flow rate of 0.00025 m3/s and viscosity 0.001 Pascal second is applied. Later, the fracture simulation was run on 12 core samples collected from the same depths in a lab. …

Development Of Quantitative Structure Activity Relationships (Qsars) For Predicting The Aggregation Of Tio2 Nanoparticles Under Favorable Conditions, Jaewoong Lee

Department of Civil and Environmental Engineering: Faculty Publications

This study developed multi-linear regression (MLR) quantitative structure-activity relationships (QSARs) to predict n-TiO₂ aggregation in the presence of high concentrations of representative emerging organic contaminants (EOCs), which presented favorable conditions to interaction with n-TiO₂. The largest diameter change (Δ 517 nm at 0 h and Δ 1164 nm at 12 h) of n-TiO₂ was observed by estrone, while the smallest diameter change (Δ -114 nm at 0 h and – 4 nm at 12 h) was observed by lincomycin during experimental periods. In addition, the zeta potential changes of n-TiO₂ were …

Characterizing Chemistry And Microbiomes During Continuous Anaerobic Codigestion Of Organics And Cattle Manure Digestate, Emily V. Schmitz, Hunter W. Schroer, Timothy E. Mattes, Craig L. Just

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

We characterized chemical and microbial responses to changes in the carbon-to-nitrogen ratio (C:N) and organic loading rate (OLR) during anaerobic codigestion (ACoD) of cattle manure digestate mixed with industrial organics. C:Ns of 25 and 35, both operating at OLRs ≤ 4 gVS L-1 d-1, sustained methane production averages of 0.36 ± 0.03 L gVS-1 d-1 and 0.32 ± 0.05 L gVS-1 d-1, respectively, throughout a 15-day period. Using 16S rRNA high-throughput sequencing coupled with PICRUSt2, taxonomy and predicted gene abundances were mapped to the major ACoD stages. C:N (25, 35) and the OLR (2, 4 gVS L-1 d-1) had minimal …

New Models For Estimating Minimum Miscibility Pressure Of Pure And Impure Carbon Dioxide Using Artificial Intelligence Techniques, Attia Attia, Ahmed Ashraf Soliman Eng., John Shahat Eng., Sayed Gomaa Prof., Fares Ashraf El Salamony Prof.

Petroleum Engineering and Gas

CO2 miscible flooding stands out as one of the most-commonly employed and promising processes in enhanced oil recovery. The key factor for ensuring success in designing and executing CO2 injection projects lies in the precise determination of the Minimum Miscibility Pressure (MMP). Despite significant research endeavors in measuring and predicting the MMP through the use of empirical, analytical, numerical, and experimental approaches, the need for a comprehensive, accurate, efficient, and easy-to-use model remains. In response to this gap, our study developed various predictive models with 205 datasets, including well-established ones such as Artificial Neural Network (ANN), Random Forest (RF), and …

How Can Generative Ai (Genai) Enhance Or Hinder Qualitative Studies? A Critical Appraisal From South Asia, Nepal, Niroj Dahal

The Qualitative Report

Qualitative researchers can benefit from using generative artificial intelligence (GenAI), such as different versions of ChatGPT—GPT-3.5 or GPT-4, Google Bard—now renamed as a Gemini, and Bing Chat—now renamed as a Copilot, in their studies. The scientific community has used artificial intelligence (AI) tools in various ways. However, using GenAI has generated concerns regarding potential research unreliability, bias, and unethical outcomes in GenAI-generated research results. Considering these concerns, the purpose of this commentary is to review the current use of GenAI in qualitative research, including its strengths, limitations, and ethical dilemmas from the perspective of critical appraisal from South Asia, Nepal. …

Selective Targeting Of Microglia By Quantum Dots And Green Synthesis Of Metal Organic Biohybrids; Applications In Dynamic Cell And Assay Systems, Navya Uppu

Doctoral Dissertations

Neurological disorders are the leading cause of physical and cognitive disability across the globe, currently affecting approximately 15% of the worldwide population. Part of the glioma microenvironment are microglia, resident immune cells of the CNS that were thought to be involved in the pathogenesis of diverse neurodegenerative diseases. Though it remains uncertain what triggers microglial activation in these disorders, targeting and tracking microglial functions using nanotools like Quantum Dots (QDs) could help us elucidate them in such neurological diseases. This research focuses on the comparative study of different QDs formulations and their selective uptake by brain microglia in primary cultures …

Development And Characterization Of Injectable, Cell-Encapsulated Chitosan-Genipin Hydrogels, Tyler R. Priddy-Arrington

Doctoral Dissertations

Over 150,000 patients undergo lower extremity amputation every year in the United States, most commonly caused by complications due to diabetes mellitus, peripheral vascular disease, and trauma. Diseased or damaged tissues that are unable to naturally repair themselves must either be fully removed or replaced, otherwise the injuries can lead to further complications such as infection or death. Tissue resection and amputation, as forms of removing damaged tissue, are not favorable to patients as they can cause pain, reduce mobility, and negatively impact quality of life. However, replacing lost or damaged tissues with donor tissues carries the risks of tissue …

Integration Of Advanced Qualification Program Into Aviation Education, Jorge L. D. Albelo, Victor Fraticelli Rivera, Robert L. Thomas

Journal of Aviation Technology and Engineering

The Federal Aviation Administration places aviation safety as a top priority, continuously striving to improve safety standards within the National Airspace System. In 2004, the Federal Aviation Administration introduced the Advanced Qualification Program (AQP) as an alternative methodology for pilot training and evaluation. This study explores the impact of AQP-centered aviation education on student performance, particularly in the context of learning advanced jet transport systems. The AQP model, based on aligning training with operational aviation requirements, emphasizes cognitive skill training and evaluation. Theoretical foundations underpinning this study include Karp’s integrated aviation learning model, which seamlessly integrates various instructional approaches, fostering …

Development Of An In Vitro 3-Dimensional Co-Culture Human Colorectal Cancer Model In Microfluidic Devices, Abby Jens

Master's Theses

Colorectal cancer is the second most common cause of cancer-related deaths in the United States, with the relative 5-year survival rate for distant stage cancer being only 14%. The most common treatment for colorectal cancer is with chemotherapeutic drugs; however, the discovery of these drugs is costly, time-consuming, and often requires the use of animal models that do not yield results that translate to clinical trials. Due to these shortcomings, researchers seek to develop physiologically relevant in vitro tumor models that more accurately mimic the tumor microenvironment for cheaper and faster high-throughput drug screening. The aim of this research was …

The Santa Clara, 2024-03-01, Santa Clara University

The Santa Clara

No abstract provided.

Development Of A Cell Culture Incubator Capable Of Providing A Hypoxic Environment, Grant Austin Coe

Master's Theses

In order to perform more robust and physiologically relevant research, the Microphysiological Systems laboratory required a method of culturing cells where the level of oxygen could be adjusted. To fulfill this need, I designed and manufactured a hypoxic cell culture incubator. I employed a Quality Function Deployment to understand the customer requirements and convert them into engineering specifications. Based on these specifications, I created various conceptual designs. I evaluated the conceptual designs as compared to existing products and decided to move forward with the control system separated from a small, standard chamber. I developed the circuitry schematics for the temperature …

Fabrication And Characterization Of Quad-Component Bioinspired Hydrogels To Model Elevated Fibrin Levels In Central Nervous Tissue Scaffolds, Jennifer Steele, Dany J. Munoz-Pinto

Engineering Faculty Research

Multicomponent interpenetrating polymer network (mIPN) hydrogels are promising tissue-engineering scaffolds that could closely resemble key characteristics of native tissues. The mechanical and biochemical properties of mIPNs can be finely controlled to mimic key features of target cellular microenvironments, regulating cell-matrix interactions. In this work, we fabricated hydrogels made of collagen type I (Col I), fibrin, hyaluronic acid (HA), and poly (ethylene glycol) diacrylate (PEGDA) using a network-by-network fabrication approach. With these mIPNs, we aimed to develop a biomaterial platform that supports the in vitro culture of human astrocytes and potentially serves to assess the effects of the abnormal deposition of …

Root And Causes Of Skilled Labor Shortage In Construction Industry: Comprehensive Literature Review, Nicholas Hardy, Carolina Barbosa-Resende, James Kereri, Arash Taghinezhad

The Professional Constructor

The skilled labor shortage is well documented from a historical perspective via studies focusing various construction trades such as carpentry, mechanical, electric and plumbing, and tile setters. Causes of such shortages such as industry image, college as a preferred choice after high school, and construction being a last resort have been investigated extensively. Consequently, possible solutions ranging from amplifying shop classes in high school to intensifying recruiting efforts for union training programs have all been addressed throughout the last 40 years. However, recent studies have focused on identifying the magnitude and reach of the skilled labor gap while limited attention …

Empathy, Education, And Awareness: A Vr Hackathon’S Approach To Tackling Climate Change, Noor Alqallaf, Dalia W. Elnagar, Sherif G. Aly, Khalil I. Elkhodary, Rami Ghannam

Faculty Journal Articles

Climate change education is crucial for fostering informed and engaged future generations. However, traditional pedagogies often fail to engage learners fully and provide real-world, experiential learning. This paper presents a novel approach to climate change education through a three-day virtual reality (VR) hackathon. The hackathon focused on four United Nations (UN) Sustainable Development Goals (SDGs)—Quality Education, Affordable and Clean Energy, Sustainable Cities and Communities, and Climate Action. Using VR technology and game design software, engineering students worked in teams. They competed against each other in designing immersive environments that demonstrated their understanding of these SDGs and climate change. Our goal …

Dielectric Properties Of Polycrystalline And Single-Crystal Magnesium Oxide At High Temperatures, Alan Devoe, Hung Trinh, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The electrical properties of high-purity magnesium oxide (MgO) samples sintered between 1500 and 1650°C were investigated up to 800°C. Dielectric constant, loss tangent and electrical conductivity were measured between 25 and 800°C. Optimum electrical properties were obtained for the sample sintered at 1600°C. The impurities in polycrystalline and single crystal MgO were discussed to understand their effect on electrical properties and the role of grain boundaries. Higher dielectric losses of polycrystalline samples as compared to the single crystal MgO were attributed to the presence of grain boundaries. MgO could be a useful dielectric material for capacitor applications up to 600°C.

Best Practices For Recruitment And Retention Of Transportation Professionals, Chris Van Dyke, Bryan Gibson, Sarah Mccormack, Merl Hackbart, Doug Kreis

Kentucky Transportation Center Research Report

Many public sector agencies, including state departments of transportation (DOTs), have long found recruiting and retaining staff a daunting challenge. Lured by the promise of higher salaries in the private sector, many people are reluctant to sacrifice their long-term earnings potential to pursue public service. And with the quality of fringe benefits (e.g., retirement plans, health insurance) offered by public agencies having declined gradually, it is even more difficult to persuade prospective employees to accept a lower salary. Many studies over the past 15—20 years have looked at methods for solving the problem of recruitment and retention within the context …

Uncovering The Critical Drivers Of Blockchain Sustainability In Higher Education Using A Deep Learning-Based Hybrid Sem-Ann Approach, Mohammed Alshamsi, Mostafa Al-Emran, Tugrul Daim, Mohammed A. Al-Sharafi, Gulin Idil Sonmezturk Bolatan, Khaled Shaalan

Engineering and Technology Management Faculty Publications and Presentations

The increasing popularity of Blockchain technology has led to its adoption in various sectors, including higher education. However, the sustainability of Blockchain in higher education is yet to be fully understood. Therefore, this research examines the determinants affecting Blockchain sustainability by developing a theoretical model that integrates the protection motivation theory (PMT) and expectation confirmation model (ECM). Based on 374 valid responses collected from university students, the proposed model is evaluated through a deep learning-based hybrid structural equation modeling (SEM) and artificial neural network (ANN) approach. The PLS-SEM results confirmed most of the hypotheses in the proposed model. The sensitivity …

Immersive Virtual Reality-Based Learning As A Supplement For Biomedical Engineering Labs: Challenges Faced And Lessons Learned, Ishita Tandon, Vitali Maldonado, Megan Wilkerson, Amanda Walls, Raj R. Rao, Mostafa Elsaadany

Biomedical Engineering Faculty Publications and Presentations

Introduction: Immersive virtual reality (VR) based laboratory demonstrations have been gaining traction in STEM education as they can provide virtual hands-on experience. VR can also facilitate experiential and visual learning and enhanced retention. However, several optimizations of the implementation, in-depth analyses of advantages and trade-offs of the technology, and assessment of receptivity of modern techniques in STEM education are required to ensure better utilization of VR-based labs.

Methods: In this study, we developed VR-based demonstrations for a biomolecular engineering laboratory and assessed their effectiveness using surveys containing free responses and 5-point Likert scale-based questions. Insta360 Pro2 camera and Meta Quest …

Utilization Of Caputo Fractional Derivative In Mhd Nanofluid Flow With Soret And Thermal Radiation Effects, Harshad Patel, Gopal Nanda

Applications and Applied Mathematics: An International Journal (AAM)

In existence of heat diffusion and thermal radiation, an analytical equation is found for unsteady MHD flow past an exponentially accelerating vertical plate in optically thick water based nanofluid. The governing equations are made dimensionless by similarity transformation. A definition of Caputo fractional derivative is applied to generalize governing system of partial differential equations. Laplace transform techniques are applied and obtained the analytical solutions of proposed problems. For a physical point of view, numerical results are obtained using MATLAB software and presented via graphs. From the results, it is concluded that magnetic fields tend to reduce velocity. It is also …

Spontaneous Alignment Of Myotubes Through Myogenic Progenitor Cell Migration, Lauren E. Mehanna, Adrianna R. Osborne, Charlotte A. Peterson, Brad J. Berron

Chemical and Materials Engineering Faculty Publications

In large-volume muscle injuries, widespread damage to muscle fibers and the surrounding connective tissue prevents myogenic progenitor cells (MPCs) from initiating repair. There is a clinical need to rapidly fabricate large muscle tissue constructs for integration at the site of large volume muscle injuries. Most strategies for myotube alignment require microfabricated structures or prolonged orientation times. We utilize the MPC’s natural propensity to close gaps across an injury site to guide alignment on collagen I. When MPCs are exposed to an open boundary free of cells, they migrate unidirectionally into the cell-free region and align perpendicular to the original boundary …

Sustainability Of Apparel Exporting Industry Facilities In South Asia, Sree L. Anilkuma, George H. Berghorn, M.G. Matt Syal

The Professional Constructor

The apparel industry’s contribution to the gross domestic product in South Asian countries is significant and provides livelihoods for millions of people in this region. Although this industry’s contribution towards the economy is substantial, its negative impact on the environment and the working conditions have always been critical issues of concern. The two countries of emphasis in this research, Bangladesh, and India, have experienced numerous garment factory accidents in the form of building collapses, factory fires, and boiler explosions, which have killed and injured thousands of workers. These incidents have brought attention on the need to improve poor facilities and …

Evaluation Of Ndot’S Sediment Barrier Practices Using Performance Data, Michael A. Perez, Wesley N. Donald, J. Blake Whitman, Brian G. Roche

Nebraska Department of Transportation: Research Reports

To protect waterways adjacent to construction projects with disturbed land, a 50 ft (15 m) vegetated buffer or equivalent sediment controls are required. However, there is little guidance on the effectiveness of vegetated buffers in removing sediment or how sediment barriers can aid shorter buffers or replace buffers. A modeling methodology was developed and used to determine the performance of 11,664 50 ft (15 m) vegetated buffer configurations with Nebraska conditions; sediment capture averaged 92.6% and ranged from 18.5% to 99.5%. To determine the performance of Nebraska Department of Transportation standard and modified sediment barrier installations, a large-scale testing methodology …

Techno-Economic Feasibility Of Polyhydroxybutyrate (Phb) Production From Corn Stover, Jey-R Ventura, Ruby Lynn Ventura

The Philippine Agricultural Scientist

This research evaluated the techno-economic feasibility of polyhydroxybutyrate (PHB) production using corn stover as a substrate for the fermentation process. The target PHB plant production was set at 1000 t PHB per yr, with a daily production of about 3 t PHB. The required corn stover biomass was around 12 000 t per yr. The economic analysis of this study suggested that 91.13 M US$ is needed to put up the targeted plant production capacity, with 94% of the total investment to be allotted to the direct fixed capital cost. Annual operating cost was rated at 4.71 M US$ per …

A Comparison Of Western And Eastern Soft Systems Approaches, John L. Anaya, John L. Anaya, John L. Anaya

Master's Theses

Soft System Approaches have been developed worldwide to help problem-solvers and decision-makers develop solutions to complex problems, such as aerospace systems. Soft System Approaches were designed to help lower the disorder of developing a complex system by increasing understanding of a situation. Four Soft System Approaches were investigated, two from the West and two from the East. Within the context of the paper, the West refers to thought patterns associated with thinkers and scientists in Europe and North America, and the East refers to those from and around China. The two from the West are Peter Checkland’s Soft Systems Methodology …

Nonlinear Interactions Of Sea‐Level Rise And Storm Tide Alter Extreme Coastal Water Levels: How And Why?, H. Moftakhari, D. F. Muñoz, A. Akbari Asanjan, A. Aghakouchak, Hamid Moradkhani, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Sea-level rise (SLR) increasingly threatens coastal communities around the world. However, not all coastal communities are equally threatened, and realistic estimation of hazard is difficult. Understanding SLR impacts on extreme sea level is challenging due to interactions between multiple tidal and non-tidal flood drivers. We here use global hourly tidal data to show how and why tides and surges interact with mean sea level (MSL) fluctuations. At most locations around the world, the amplitude of at least one tidal constituent and/or amplitude of non-tidal residual have changed in response to MSL variation over the past few decades. In 37% of …

Spatiotemporal Dispersion Compensation For A 200-Thz Noncollinear Optical Parametric Amplifier, William P. Carbery, Laurie A. Bizimana, Matthew S. Barclay, Nicholas D. Wright, Paul H. Davis, William B. Knowlton, Ryan D. Pensack, Paul C. Arpin, Daniel B. Turner

Materials Science and Engineering Faculty Publications and Presentations

A noncollinear optical parametric amplifier (NOPA) can produce few-cycle femtosecond laser pulses that are ideally suited for time-resolved optical spectroscopy measurements. However, the nonlinear-optical process giving rise to ultrabroadband pulses is susceptible to spatiotemporal dispersion problems. Here, we detail refinements, including chirped-pulse amplification (CPA) and pulse-front matching (PFM), that minimize spatiotemporal dispersion and thereby improve the properties of ultrabroadband pulses produced by a NOPA. The description includes a rationale behind the choices of optical and optomechanical components, as well as assessment protocols. We demonstrate these techniques using a 1 kHz, second-harmonic Ti:sapphire pump configuration, which produces ∼5-fs duration pulses that …

Layered Mantle Flow Field Associated With Plate Kinematics And Slab Modulation Underneath The Horseshoe-Shaped Banda Arc-Islands, Sijia Li, Fansheng Kong, Kelly H. Liu, Stephen S. Gao

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The Banda Arc-Continent Collision Zone Signifies One Of The Most Seismically Active And Tectonically Intricate Zones. The High Convergence Rate Across The Region, Coupled With The Exceptionally Arcuate Arc And Subducted Slab, Makes It An Ideal Locale For Investigating Interactions Between Plate (Slab) Kinematics And Plastic Flow In The Asthenosphere, Which Can Be Diagnosed By Seismic Anisotropy From Shear Wave Splitting Analyses. In Total, 206 Pairs Of Splitting Measurements Using Teleseismic SKS, SKKS, And PKS, Along With 43 Pairs Using Local S Phases, Are Obtained By Utilizing Broadband Seismic Data From Five Permanent Seismic Stations. To Reduce The Ambiguity In …

Neonatal Respiratory Therapy Interface, Kennedy Austin, Evan Manley, Parker Murray, Harrison Oen

Biomedical Engineering

This Final Report reviews and outlines the scope, objectives, and deliverables for the BCPAP Interface Redesign project, aimed at enhancing the functionality, usability, and patient experience of the existing BCPAP interface. It also includes detailed testing results and manufacturing plans for the device prototype. The current system has challenges in universal usability, time constraints, and patient comfort, which this project intends to address effectively. The goal of this project is to reevaluate and redesign the interface of the bubble continuous positive air pressure (BCPAP) machine’s attachment site with the infant. Due to the millions of premature neonates and thousands of …