Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 52561 - 52590 of 197100

Full-Text Articles in Engineering

Shale Wettability: Data Sets, Challenges, And Outlook, Muhammad Arif, Yihuai Zhang, Stefan Iglauer Jan 2021

Shale Wettability: Data Sets, Challenges, And Outlook, Muhammad Arif, Yihuai Zhang, Stefan Iglauer

Research outputs 2014 to 2021

© 2021 American Chemical Society. The wetting characteristics of shale rocks at representative subsurface conditions remain an area of active debate. A precise characterization of shale wettability is essential for enhanced oil and gas recovery, containment security during CO2 geo-storage, and flow back efficiency during hydraulic fracturing. While several methods were utilized in the literature to evaluate shale wettability (e.g., contact angle measurements, spontaneous imbibition method,and NMR method), we here review the recently published data sets on shale contact angle measurements. The objectives of this review are to (a) develop a repository of the recent shale wettability data sets using …


Graphene Nanoplatelets Suspended In Different Basefluids Based Solar Collector: An Experimental And Analytical Study, Omer A. Alawi, Haslinda Mohamed Kamar, Abdul Rahman Mallah, Hussein A. Mohammed, Mohd Aizad Sazrul Sabrudin, Omar A. Hussein, Salim Newaz Kazi, Gholamhassan Najafi Jan 2021

Graphene Nanoplatelets Suspended In Different Basefluids Based Solar Collector: An Experimental And Analytical Study, Omer A. Alawi, Haslinda Mohamed Kamar, Abdul Rahman Mallah, Hussein A. Mohammed, Mohd Aizad Sazrul Sabrudin, Omar A. Hussein, Salim Newaz Kazi, Gholamhassan Najafi

Research outputs 2014 to 2021

© 2021 by the authors. Licensee MDPI, Basel, Switzerland. A flat plate solar collector (FPSC) was analytically studied, with functionalized graphene nanoplatelets (f-GNPs) as its working fluid. Four samples (wt % nanofluids) were prepared in different base fluids such as ethylene glycol (EG), distilled water (DW):EG (70:30), and DW:EG (50:50). Experimental results (via DW) were used to verify the effectiveness of the analytical model. Some of the operating conditions were taken into account in this research, including temperatures, power, and mass flow rates. Experimental techniques were used to elucidate the modified nanofluids’ physicochemical properties, such as its particle sizes, stability, …


Characterization And Analysis Of Naturally Fractured Gas Reservoirs Based On Stimulated Reservoir Volume And Petro-Physical Parameters, Ali Al-Rubaye, Ahmed Al-Yaseri, Muhammad Ali, Hisham Ben Mahmud Jan 2021

Characterization And Analysis Of Naturally Fractured Gas Reservoirs Based On Stimulated Reservoir Volume And Petro-Physical Parameters, Ali Al-Rubaye, Ahmed Al-Yaseri, Muhammad Ali, Hisham Ben Mahmud

Research outputs 2014 to 2021

© 2021, The Author(s). Fracture is one of the most important geological phenomena that affect the production of hydrocarbon compounds in broken carbonate reservoirs. However, fracture controlling factors must be combined with well data to achieve accurate fracture modeling. Therefore, structural data, drilling data, well flow diagrams, cores data, wells production data, and dynamic reservoir data have been considered here. Finally, by combining the above-mentioned information and through statistical and mathematical methods, the mechanism of fracture creation, general trends, and dominant fracture patterns are determined. These patterns are directly related to the tectonic regime and the stresses governing the region. …


Experimental Study On Repeatedly Loaded Foundation Soil Strengthened By Wraparound Geosynthetic Reinforcement Technique, Muhammad Nouman Amjad Raja, Sanjay K. Shukla Jan 2021

Experimental Study On Repeatedly Loaded Foundation Soil Strengthened By Wraparound Geosynthetic Reinforcement Technique, Muhammad Nouman Amjad Raja, Sanjay K. Shukla

Research outputs 2014 to 2021

In the recent past, the potential benefits of wraparound geosynthetic reinforcement technique for constructing the reinforced soil foundations have been reported. This paper presents the experimental study on the behaviour of model strip footing resting on sandy soil bed reinforced with geosynthetic in wraparound and planar forms under monotonic and repeated loadings. The geosynthetic layers were laid according to the reinforcement ratio to minimise the scale effect. It is found that for the same amount of reinforcement material, the wraparound reinforced model resulted in less settlement in comparison to planar reinforced models. The efficiency of wraparound reinforced model increased with …


Performance Of Fft-Ofdm Versus Dwt-Ofdm Under Compressive Sensing, Zainab Hdeib Al-Shably, Zahir M. Hussain Jan 2021

Performance Of Fft-Ofdm Versus Dwt-Ofdm Under Compressive Sensing, Zainab Hdeib Al-Shably, Zahir M. Hussain

Research outputs 2014 to 2021

In this work, we present a comparative study on the performance of Fourier-based OFDM (FFT-OFDM) and wavelet-based OFDM (DWT-OFDM) under compressive sensing (CS). Transmission over FFT-OFDM and DWT-OFDM, which has been made under different baseband modulation schemes such as Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Key (QPSK), Quadrature amplitude modulation (16QAM) and (64QAM) has been considered. From numerical simulation results, it is observed that the Wavelet-based OFDM system outperforms Fourier based OFDM when the Quadrature Amplitude Modulation is 16QAM and 64QAM within the signal to noise ratios range 30 to 40 dB. Although CS is more efficient in …


Editorial: Hexagonal Close-Packed Metals And Alloys: Processing, Microstructure And Properties, Liang-Yu Chen, Linjiang Chai, Lai-Chang Zhang Jan 2021

Editorial: Hexagonal Close-Packed Metals And Alloys: Processing, Microstructure And Properties, Liang-Yu Chen, Linjiang Chai, Lai-Chang Zhang

Research outputs 2014 to 2021

In comparison with face-centered cubic (FCC) and body-centered cubic (BCC) metals and alloys, hexagonal close-packed (HCP) metals and alloys show distinct characteristics, such as atomic site occupation, anisotropic microstructure, and fewer slip systems, owing to their HCP lattice structure. Therefore, HCP metals and alloys have distinguished processing, microstructure, and properties. Several types of HCP metals and alloys, involving titanium, zirconium, magnesium, and so on, are extensively used in a variety of industrial and military sectors. Up to date, an increased requirement is still needed to improve the understanding of the relationships among processing, microstructures, and the resultant properties of HCP …


Quantifying The Benefits Of In-Time And In-Place Responses To Remediate Acute Lnapl Release Incidents, Kaveh S. Lari, Andrew King, John L. Rayner, Greg B. Davis Jan 2021

Quantifying The Benefits Of In-Time And In-Place Responses To Remediate Acute Lnapl Release Incidents, Kaveh S. Lari, Andrew King, John L. Rayner, Greg B. Davis

Research outputs 2014 to 2021

Acute large volume spills from storage tanks of petroleum hydrocarbons as light non aqueous phase liquids (LNAPLs) can contaminate soil and groundwater and may have the potential to pose explosive and other risks. In consideration of an acute LNAPL release scenario, we explore the value of a rapid remediation response, and the value of installing remediation infrastructure in close proximity to the spill location, in effecting greater recovery of LNAPL mass from the subsurface. For the first time, a verified three-dimensional multi-phase numerical framework and supercomputing resources was applied to explore the significance of in-time and in-place remediation actions. A …


Towards Predicting Dnapl Source Zone Formation To Improve Plume Assessment: Using Robust Laboratory And Numerical Experiments To Evaluate The Relevance Of Retention Curve Characteristics, Christian Engelmann, Kaveh Sookhak Lari, Luisa Schmidt, Charles J. Werth, Marc Walther Jan 2021

Towards Predicting Dnapl Source Zone Formation To Improve Plume Assessment: Using Robust Laboratory And Numerical Experiments To Evaluate The Relevance Of Retention Curve Characteristics, Christian Engelmann, Kaveh Sookhak Lari, Luisa Schmidt, Charles J. Werth, Marc Walther

Research outputs 2014 to 2021

© 2020 The Authors We conducted multiple laboratory trials in a robust and repeatable experimental layout to study dense non-aqueous phase liquid (DNAPL) source zone formation. We extended an image processing and analysis framework to derive DNAPL saturation distributions from reflective optical imaging data, with volume balance deviations < 5.07%. We used a multiphase flow model to simulate source zone formation in a Monte Carlo approach, where the parameter space was defined by the variation of retention curve parameters. Integral and geometric measures were used to characterize the source zones and implemented into a multi-criteria objective function. The latter showed good agreement between observation data and simulation results for effective DNAPL saturation values > 0.04, especially for early stages of DNAPL migration. The common hypothesis that parameters defining the DNAPL-water retention curves are constant over time was not confirmed. Once DNAPL pooling started, the optimal fit in the parameter space was significantly different compared to the earlier DNAPL migration stages. We suspect more complex processes (e.g., …


Recent Progress Trend On Abrasive Waterjet Cutting Of Metallic Materials: A Review, Jennifer Milaor Llanto, Majid Tolouei-Rad, Ana Vafadar, Muhammad Aamir Jan 2021

Recent Progress Trend On Abrasive Waterjet Cutting Of Metallic Materials: A Review, Jennifer Milaor Llanto, Majid Tolouei-Rad, Ana Vafadar, Muhammad Aamir

Research outputs 2014 to 2021

Abrasive water jet machining has been extensively used for cutting various materials. In particular, it has been applied for difficult-to-cut materials, mostly metals, which are used in various manufacturing processes in the fabrication industry. Due to its vast applications, in-depth comprehension of the systems behind its cutting process is required to determine its effective usage. This paper presents a review of the progress in the recent trends regarding abrasive waterjet cutting application to extend the understanding of the significance of cutting process parameters. This review aims to append a substantial understanding of the recent improvement of abrasive waterjet machine process …


Experimental Investigation And Comparison Of The Thermal Performance Of Additively And Conventionally Manufactured Heat Exchangers, Ana Vafadar, Ferdinando Guzzomi, Kevin Hayward Jan 2021

Experimental Investigation And Comparison Of The Thermal Performance Of Additively And Conventionally Manufactured Heat Exchangers, Ana Vafadar, Ferdinando Guzzomi, Kevin Hayward

Research outputs 2014 to 2021

Air heat exchangers (HXs) are applicable in many industrial sectors because they offer a simple, reliable, and cost-effective cooling system. Additive manufacturing (AM) systems have sig-nificant potential in the construction of high-efficiency, lightweight HXs; however, HXs still mainly rely on conventional manufacturing (CM) systems such as milling, and brazing. This is due to the fact that little is known regarding the effects of AM on the performance of AM fabricated HXs. In this research, three air HXs comprising of a single fin fabricated from stainless steel 316 L using AM and CM methods—i.e., the HXs were fabricated by both direct …


Evaluation Of The Surface Defects And Dimensional Tolerances In Multi-Hole Drilling Of Aa5083, Aa6061, And Aa2024, Muhammad Aamir, Majid Tolouei Rad, Khaled Giasin, Ana Vafadar, Ugur Koklu, William Keeble Jan 2021

Evaluation Of The Surface Defects And Dimensional Tolerances In Multi-Hole Drilling Of Aa5083, Aa6061, And Aa2024, Muhammad Aamir, Majid Tolouei Rad, Khaled Giasin, Ana Vafadar, Ugur Koklu, William Keeble

Research outputs 2014 to 2021

Drilling is one of the most performed machining operations for riveting and assembly operations in many industrial sectors. The accuracy of the drilled holes and their surface finish play a vital role in the longevity and performance of the machined components, which, in turn, increase productivity. Therefore, this study investigated the effect of the multi-spindle drilling process on dimensional hole tolerances, such as hole size, circularity, cylindricity, and perpendicularity. In addition, the surface defects formed in the holes were examined using scanning electron microscopy. Three aluminium alloys, AA2024, AA6061, and AA5083, which are commonly used in the aerospace, automotive, and …


Hybrid Mamdani Fuzzy Rules And Convolutional Neural Networks For Analysis And Identification Of Animal Images, Hind R. Mohammed, Zahir M. Hussain Jan 2021

Hybrid Mamdani Fuzzy Rules And Convolutional Neural Networks For Analysis And Identification Of Animal Images, Hind R. Mohammed, Zahir M. Hussain

Research outputs 2014 to 2021

Accurate, fast, and automatic detection and classification of animal images is challenging, but it is much needed for many real-life applications. This paper presents a hybrid model of Mamdani Type-2 fuzzy rules and convolutional neural networks (CNNs) applied to identify and distinguish various animals using different datasets consisting of about 27,307 images. The proposed system utilizes fuzzy rules to detect the image and then apply the CNN model for the object’s predicate category. The CNN model was trained and tested based on more than 21,846 pictures of animals. The experiments’ results of the proposed method offered high speed and efficiency, …


Deep Learning Versus Spectral Techniques For Frequency Estimation Of Single Tones: Reduced Complexity For Software-Defined Radio And Iot Sensor Communications, Hind R. Almayyali, Zahir M. Hussain Jan 2021

Deep Learning Versus Spectral Techniques For Frequency Estimation Of Single Tones: Reduced Complexity For Software-Defined Radio And Iot Sensor Communications, Hind R. Almayyali, Zahir M. Hussain

Research outputs 2014 to 2021

Despite the increasing role of machine learning in various fields, very few works considered artificial intelligence for frequency estimation (FE). This work presents comprehensive analysis of a deep-learning (DL) approach for frequency estimation of single tones. A DL network with two layers having a few nodes can estimate frequency more accurately than well-known classical techniques can. While filling the gap in the existing literature, the study is comprehensive, analyzing errors under different signal-to-noise ratios (SNRs), numbers of nodes, and numbers of input samples under missing SNR information. DL-based FE is not significantly affected by SNR bias or number of nodes. …


Revised Draft Final Butte Reclaimed Areas Maintenance And Monitoring (M&M) Plan In Accordance With Butte Reclamation Evaluation System (Bres), Pioneer Technical Services, Inc. Jan 2021

Revised Draft Final Butte Reclaimed Areas Maintenance And Monitoring (M&M) Plan In Accordance With Butte Reclamation Evaluation System (Bres), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Identifying Interconnectivities Between Modular Construction Decision-Making Factors Using Clustering And Network Analysis, Mohamad Abdul Nabi, Islam H. El-Adaway Jan 2021

Identifying Interconnectivities Between Modular Construction Decision-Making Factors Using Clustering And Network Analysis, Mohamad Abdul Nabi, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Understanding the complex and unique requirements of modular construction methods has become crucial given the ongoing increase in popularity of such construction methods. In fact, studying the various modular construction factors and their interconnections to attain successful project performance is perceived to help practitioners choose the modularization strategies that are more suitable for their specific context. To this end, there is a need to better understand the interconnectivities among the various modular construction decision-making factors. As such, the paper aims to enhance the knowledge of the interactions and interdependencies among the various modular construction decision-making factors. To achieve that, the …


Smart And Emerging Technologies: Shaping The Future Of The Industry And Offsite Construction, Rayan H. Assaad, Islam H. El-Adaway, Makarand Hastak, Kim La Scola Needy Jan 2021

Smart And Emerging Technologies: Shaping The Future Of The Industry And Offsite Construction, Rayan H. Assaad, Islam H. El-Adaway, Makarand Hastak, Kim La Scola Needy

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The interest in smart, emerging technologies and offsite construction methods continues to grow. While previous studies investigated different offsite construction aspects, there is still lack of research work that explored the current and future use of smart and emerging technologies, especially those used in offsite construction. This study addresses this knowledge gap through a multi-step research methodology. First, a list of 24 technologies was identified. Second, a survey was distributed to study the current use and the experts' future perceptions of the identified technologies in offsite construction. Third, descriptive statistics and computational clustering analysis were used to quantify and classify …


Using Machine Learning To Identify The Most Critical Factors Affecting Maintenance Of Tunnels, Muaz O. Ahmed, Ramy Khalef, Gasser G. Ali, Islam H. El-Adaway Jan 2021

Using Machine Learning To Identify The Most Critical Factors Affecting Maintenance Of Tunnels, Muaz O. Ahmed, Ramy Khalef, Gasser G. Ali, Islam H. El-Adaway

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Having well-maintained transportation infrastructure systems, including tunnels, is essential for the functioning and growth of the US economy. As such, monitoring the condition of tunnels through structural evaluation and inspections is essential to maintain their level of service. However, there is a lack of research that utilizes data from previous formal inspections to model and understand the condition of tunnels in the US. Being the case, this paper tackles this research need by developing a tunnel condition rating model that identifies the most critical factors affecting maintenance of tunnels. To this end, the authors utilize random forest (RF), which is …


Electrospun Fiber Scaffolds For Engineering Glial Cell Behavior To Promote Neural Regeneration, Devan L. Puhl, Jessica L. Funnell, Derek W. Nelson, Manoj K. Gottipati, Ryan J. Gilbert Jan 2021

Electrospun Fiber Scaffolds For Engineering Glial Cell Behavior To Promote Neural Regeneration, Devan L. Puhl, Jessica L. Funnell, Derek W. Nelson, Manoj K. Gottipati, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Electrospinning is a fabrication technique used to produce nano-or micro-diameter fibers to generate biocompatible, biodegradable scaffolds for tissue engineering applications. Electro spun fiber scaffolds are advantageous for neural regeneration because they mimic the structure of the nervous system extracellular matrix and provide contact guidance for regenerating axons. Glia are non-neuronal regulatory cells that maintain homeostasis in the healthy nervous system and regulate regeneration in the injured nervous system. Electro spun fiber scaffolds offer a wide range of characteristics, such as fiber alignment, diameter, surface nano topography, and surface chemistry that can be engineered to achieve a desired glial cell response …


In-Situ Process Monitoring For Metal Additive Manufacturing (Am) Through Acoustic Technique, Md Shahjahan Hossain Jan 2021

In-Situ Process Monitoring For Metal Additive Manufacturing (Am) Through Acoustic Technique, Md Shahjahan Hossain

College of Graduate Studies: Theses & Dissertations

Additive Manufacturing (AM) is currently a widely used technology in different industries such as aerospace, medical, and consumer products. Previously it was mainly used for prototyping of the products, but now it is equally valuable for commercial product manufacturing. More profound understanding is still needed to track and identify defects during the AM process to ensure higher quality products with less material waste. Nondestructive testing becomes an essential form of testing for AM parts, where AE is one of the most used methods for in situ process monitoring. The Acoustic Emission (AE) approach has gained a reputation in nondestructive testing …


Unobtrusive Assessment Of Student Engagement Levels In Online Classroom Environment Using Emotion Analysis, Sasirekha Anbusegaran Jan 2021

Unobtrusive Assessment Of Student Engagement Levels In Online Classroom Environment Using Emotion Analysis, Sasirekha Anbusegaran

College of Graduate Studies: Theses & Dissertations

Measuring student engagement has emerged as a significant factor in the process of learning and a good indicator of the knowledge retention capacity of the student. As synchronous online classes have become more prevalent in recent years, gauging a student's attention level is more critical in validating the progress of every student in an online classroom environment. This paper details the study on profiling the student attentiveness to different gradients of engagement level using multiple machine learning models. Results from the high accuracy model and the confidence score obtained from the cloud-based computer vision platform - Amazon Rekognition were then …


Impact Of Blended Salt Anti-Icers/Deicers On Properties Of Asphalt Binders, Nurudeen A. Abidoye Jan 2021

Impact Of Blended Salt Anti-Icers/Deicers On Properties Of Asphalt Binders, Nurudeen A. Abidoye

College of Graduate Studies: Theses & Dissertations

Anyone who has ever attempted to remove a layer of ice from a roadway or sidewalk by plowing or shoveling knows it is no easy task when the ice is firmly bonded to the asphalt/concrete surface. Winter anti-icing/deicing operations are moral choices that mankind has made to combat winter storms. This research is aimed at evaluating the macro and nano structural impacts of (anti-icing/de-icing) salt on aged and unaged asphalt binders. The macro structural impacts focused on the rheological and creep properties, and the nano structural impacts focused on the surface topography, adhesion force, and modulus of asphalt binders. Rheological …


New Longitudinal Error Balancing Approaches For Closed Traverses, Jose L. Manzano Jan 2021

New Longitudinal Error Balancing Approaches For Closed Traverses, Jose L. Manzano

College of Graduate Studies: Theses & Dissertations

This study presents two novel approaches to balance the horizontal longitudinal error of closure, EC, in closed polygonal traverses. The standard procedure to balance EC is the Compass Rule. This technique reduces EC to zero by applying corrections in the lengths of all traverse sides. Those corrections are proportional to the corresponding side lengths. That is, this approach is not an error-correcting approach, but an error-balancing procedure.

The proposed new techniques are based on sensitivity analysis of EC with respect to small variations, Δi, in the lengths of all sides i = 1, …


Analysis Of Miniaturized, Circularly Polarized Antennas For Bidirectional Propagation, Mason C. Moore Jan 2021

Analysis Of Miniaturized, Circularly Polarized Antennas For Bidirectional Propagation, Mason C. Moore

College of Graduate Studies: Theses & Dissertations

Size reduction is necessary to fit the recent demand for small sized communication systems in consumer electronics. Wireless communication systems rely on antennas for long range transmission of signals, so size reduced antennas have been sought after in recent years. Also, not many antennas are designed for use in bidirectional scenarios like subways, tunnels, bridges, etc. Three sized reduced antennas with circular polarization are presented for use in bidirectional communication systems. An electrically small pattern reconfigurable array, an electrically small two-sided printed cross dipole, and a size reduced printed wideband antenna are introduced within this thesis. All antennas’ results are …


A Semi-Active Vibration Isolator For 3d Printing On Shipboard, Mohammad Z. Shahabuddin Jan 2021

A Semi-Active Vibration Isolator For 3d Printing On Shipboard, Mohammad Z. Shahabuddin

College of Graduate Studies: Theses & Dissertations

In the recent years, additive manufacturing (AM) (aka 3D printing)-has become a viable alternative to traditional manufacturing due to its unique advantages, such as enabling the fabrication of complex geometries at reduced weight and costs as well as allowing on-site fabrication for maintenance and repair. One specific application area of the AM is the navy vessels. During extended voyages, the navy vessels likely require the convenience of on-site fabrication of the malfunctioned parts. However, the shipboard equipment suffers from a broad range of external excitations arising not only from the waves but also from the vessel’s engines, which …


Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu Jan 2021

Quality Assurance Of Lightweight Structures Via Phase-Based Motion Estimation, Ikenna E. Ifekaonwu

College of Graduate Studies: Theses & Dissertations

In recent years, lightweight structures have become mature and adopted in various applications. The importance of quality assurance cannot be overemphasized hence extensive research has been conducted to assess the quality of lightweight structures. This study investigates a novel process that exploits motion magnification to investigate the damage characteristics of lightweight mission-critical parts. The goal is to assure the structural integrity of 3D printed structures and composite structures by determining the inherent defects present in the part by exploiting their vibration characteristics. The minuscule vibration of the structure was recorded with the aid of a high-speed digital camera, and the …


The Development Of A Holistic Quality Score Using In-Situ Monitoring Of Laser Powder Bed Fusion, Ryan Daigneault Jan 2021

The Development Of A Holistic Quality Score Using In-Situ Monitoring Of Laser Powder Bed Fusion, Ryan Daigneault

College of Graduate Studies: Theses & Dissertations

Additive manufacturing processes allow for a great degree of flexibility in terms of part production. The process is autonomous once the part has started printing in that the operator generally does not need to intervene until the part is finished. One issue that this introduces, however, is an inability to determine part quality during the printing process. Once a part has started printing, the operator must either wait until the part is finished or regularly check on the part during the print to determine the part quality. Using data gathered from multiple sensors, a quality score can be used to …


Experimental And Numerical Investigation Of Naca Airfoil Wing With Winglets, Courtney Danielle Bachmann Jan 2021

Experimental And Numerical Investigation Of Naca Airfoil Wing With Winglets, Courtney Danielle Bachmann

College of Graduate Studies: Theses & Dissertations

This research was performed in order to study wingtip devices and, in particular, winglets. Winglets are attached to commercial aircraft for the purpose of reducing induced drag caused by wake vortices on the wingtip. A winglet device can save an aircraft anywhere from 3-7% in fuel consumption. Over the course of a year, this can add up to hundreds of thousands of dollars saved. This research consisted of two parts: one part experiment and one part equipment design. The latter phase of this research examined various methods of testing in a subsonic wind tunnel laboratory setting. Experimental results found with …


Reclamation Of Fused Silica From Investment Shells Used For Casting Steel, Samuel L. Holt Jan 2021

Reclamation Of Fused Silica From Investment Shells Used For Casting Steel, Samuel L. Holt

College of Graduate Studies: Theses & Dissertations

Fused silica is widely used for investment casting shell molds. Fused silica shells are discarded after being used for casting one time. This is due to the transformation of fused silica to beta cristobalite above 1652℉ (900℃). To reduce cost and waste of investment casting foundries, this study is exploring a method to inhibit transformation of fused silica and reclaim it from high temperature investment casting shells. This research has employed firing to minimalize fused silica transformation to cristobalite. The phase transformation is minimalized due to sintering and coarsening of the particles during firing. Coarsening reduces surface area to volume …


Design And Development Of Soft Earthworm Robot Driven By Fibrous Artificial Muscles, Beau Ragland Jan 2021

Design And Development Of Soft Earthworm Robot Driven By Fibrous Artificial Muscles, Beau Ragland

College of Graduate Studies: Theses & Dissertations

Earthworm robots have proven their viability in the fields of medicine, reconnaissance, search and rescue, and infrastructure inspection. These robots are traditionally typically hard-shelled and must be tethered to whatever drives their locomotion. For this reason, truly autonomous capabilities are not yet feasible. The goal of this thesis is to introduce a robot that not only sets the groundwork for autonomous locomotion, but also is safe for human-robot interaction. This was done by ensuring that the actuation principle utilized by the robot is safe around humans and can work in an untethered design. Artificial muscle actuation allowed for these prerequisites …


Development Of A Mathematical Model For Galvanic Cells, Joshua C. Johnson Jan 2021

Development Of A Mathematical Model For Galvanic Cells, Joshua C. Johnson

College of Graduate Studies: Theses & Dissertations

It is possible to utilize principles of equilibrium thermodynamics to model the voltage a battery renders as it powers a load in time and discharges. Similarly, consideration of the internal chemistry inside a battery, or galvanic cell, enables modeling thereof. This paper builds upon these principles and presents a derivation of the Nernst equation that utilizes this result to model discharge curves in time for different types of batteries. The Nernst equation relates chemical activity of the reagents inside a battery to the open circuit voltage rendered by the system. By combining the Nernst equation with Faraday's laws of electrolysis, …