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Full-Text Articles in Engineering

Effective Systems For Insider Threat Detection, Muhanned Qasim Jabbar Alslaiman Jan 2023

Effective Systems For Insider Threat Detection, Muhanned Qasim Jabbar Alslaiman

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Insider threats to information security have become a burden for organizations. Understanding insider activities leads to an effective improvement in identifying insider attacks and limits their threats. This dissertation presents three systems to detect insider threats effectively. The aim is to reduce the false negative rate (FNR), provide better dataset use, and reduce dimensionality and zero padding effects. The systems developed utilize deep learning techniques and are evaluated using the CERT 4.2 dataset. The dataset is analyzed and reformed so that each row represents a variable length sample of user activities. Two data representations are implemented to model extracted features …

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Fuzzing Php Interpreters By Automatically Generating Samples, Jacob S. Baumgarte Jan 2023

Fuzzing Php Interpreters By Automatically Generating Samples, Jacob S. Baumgarte

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Modern web development has grown increasingly reliant on scripting languages such as PHP. The complexities of an interpreted language means it is very difficult to account for every use case as unusual interactions can cause unintended side effects. Automatically generating test input to detect bugs or fuzzing, has proven to be an effective technique for JavaScript engines. By extending this concept to PHP, existing vulnerabilities that have since gone undetected can be brought to light. While PHP fuzzers exist, they are limited to testing a small quantity of test seeds per second. In this thesis, we propose a solution for …

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Modeling, Simulation, And Hardware Testing Of A Noise-Canceller Adc Architecture, Ethan R. Rando Jan 2023

Modeling, Simulation, And Hardware Testing Of A Noise-Canceller Adc Architecture, Ethan R. Rando

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Analog-to-Digital Converters (ADCs) are essential elements of most complex electronic devices. ADCs allow for an analog signal to be converted into the digital domain, and thus interpreted by a digital circuit or model. While ADCs are extremely common, they are not immune from common tradeoffs when being designed and implemented. The most prominent tradeoff when selecting or designing an ADC is whether to pursue a high conversion rate or a high resolution on the digital output. There are some ADC designs that allow for relatively high resolution while maintaining a respectable conversion rate, however these designs often come at the …

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Calpains In The Peripheral Nerve And During Demyelination And Degeneration In Rodents, John A. Miller Jan 2023

Calpains In The Peripheral Nerve And During Demyelination And Degeneration In Rodents, John A. Miller

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Myelin formed around axons ensures rapid and efficient action potential propagation. Disruption of myelinated axons in the peripheral nervous system (PNS) often causes nerve conduction failure, neurological symptoms and can lead to long-term disability. Calpains are calcium dependent cysteine proteases that play many roles during both normal physiology and pathogenesis. Calpain-1 (CAPN1) and calpain-2 (CAPN2) are key calpain paralogs found in the nervous system and potentially have opposing roles, with CAPN2 having a more neurodegenerative function. In the central nervous system (CNS), calpains have a role in developmental myelination as well as in the pathological demyelination of multiple sclerosis and …

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Frostflex, Isaac Edmondson, Caleb Edmondson, Joey Esker, Nadine Salem Jan 2023

Frostflex, Isaac Edmondson, Caleb Edmondson, Joey Esker, Nadine Salem

Williams Honors College, Honors Research Projects

Research has shown that the majority of heat lost during physical exercise leaves the body through the hands, feet, and the face. Our design project seeks to develop cooling glove technology to increase the rate at which heat leaves the body during recovery from physical exertion. The goal of this project was to investigate different ways in which heat absorption through various mediums can be manipulated and scaled into an adaptable, flexible design in which athletes of all levels, from recreational to professional, can improve their physical performance with the use of our gloves. Deliverables include a functional prototype, product …

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Unsupervised-Based Distributed Machine Learning For Efficient Data Clustering And Prediction, Vishnu Vardhan Baligodugula Jan 2023

Unsupervised-Based Distributed Machine Learning For Efficient Data Clustering And Prediction, Vishnu Vardhan Baligodugula

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Machine learning techniques utilize training data samples to help understand, predict, classify, and make valuable decisions for different applications such as medicine, email filtering, speech recognition, agriculture, and computer vision, where it is challenging or unfeasible to produce traditional algorithms to accomplish the needed tasks. Unsupervised ML-based approaches have emerged for building groups of data samples known as data clusters for driving necessary decisions about these data samples and helping solve challenges in critical applications. Data clustering is used in multiple fields, including health, finance, social networks, education, and science. Sequential processing of clustering algorithms, like the K-Means, Minibatch K-Means, …

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Experimental And Numerical Studies On The Projective Dye Visualization Velocimetry In A Squared Vertical Tube, Mark Bradley Johnson Jan 2023

Experimental And Numerical Studies On The Projective Dye Visualization Velocimetry In A Squared Vertical Tube, Mark Bradley Johnson

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In fluid flow experiments, there have been numerous techniques developed over the years to measure velocity. Most popular techniques are non-intrusive such as particle image velocimetry (PIV), but these techniques are not suitable for all applications. For instance, PIV cannot be used in examining in-vivo measurements since the laser is not able to penetrate through the patient, which is why medical applications typically use X-rays. However, the images obtained from X-rays, in particular digital subtraction angiography, are projective images which compress 3D flow features onto a 2D image. Therefore, when intensity techniques, such as optical flow method (OFM), are applied …

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Effects Of Elastic Anisotropy On Residual Stress Measurements Performed Using The Hole-Drilling Technique, Joshua T. Ward Jan 2023

Effects Of Elastic Anisotropy On Residual Stress Measurements Performed Using The Hole-Drilling Technique, Joshua T. Ward

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In the present work, the variation in through-thickness residual stress profiles driven by elastic anisotropy is investigated using the incremental hole-drilling method. The standardized hole-drilling technique allows for the calculation of in-plane stresses based on measured surface strains, however, these calculations assume elastic isotropy. The assumption of elastic isotropy allows for the material constants to be reduced down to two values, however, this assumption is invalid for many materials used in aerospace design. These materials are often times elastically anisotropic, which leads to inaccuracy and uncertainty in measured stress profiles. An interference fit ring and plug sample was designed, using …

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Effect Of Size And Shape Parameters On Microstructure Of Additively Manufactured Inconel 718, Showmik Ahsan Jan 2023

Effect Of Size And Shape Parameters On Microstructure Of Additively Manufactured Inconel 718, Showmik Ahsan

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Additive Manufacturing (AM) methods are promising in applications where complex part geometries, exotic materials and small lot sizes are required. Aerospace manufacturing stands to use AM methods extensively in the future, and frequently requires temperature- and corrosion-resistant alloy materials such as Inconel 718. However, the microstructural evolution of Inconel 718 during additive manufacturing is poorly understood and depends on part size and shape. We studied the microstructure of Inconel 718 parts manufactured by Laser Powder Bed Fusion in order to further elucidate these dependencies. Microstructural analysis, SEM imaging, EBSD scans and Microhardness testing were performed.

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Rankine Cycle Investigation On Meeting Power And Thermal Requirements Of High-Speed Aircraft, Jacob J. Spark Jan 2023

Rankine Cycle Investigation On Meeting Power And Thermal Requirements Of High-Speed Aircraft, Jacob J. Spark

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This work is investigating a dual mode Rankine cycle for aircraft applications, specifically meeting vehicle thermal and power requirements. This multiconfigurational approach allows the Thermal Management System (TMS) to be controlled based on aircraft needs. In this design, waste heat is removed from critical areas of the aircraft (e.g., propulsion, structure, subsystems) using the fuel as a heat sink. Hot fuel is then forced through a heat exchanger actively boiling water. The vapor byproduct is fed to a turbine coupled to a generator, providing power. The low-pressure steam is then condensed using cold fuel drawn from its tank; however, when …

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Multi-Variable Phase And Gain Calibration For Multi-Channel Transmit Signals, Ryan C. Ball Jan 2023

Multi-Variable Phase And Gain Calibration For Multi-Channel Transmit Signals, Ryan C. Ball

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A method for software-defined radio array calibration is presented. The method implements a matched filter approach to calculate the phase shift between channels. The temporal stability of the system and calibration coefficients are shown through the standard deviation over the course of four weeks. The standard deviation of the phase correction was shown to be less than 2 deg. for most channels in the array and within 8 deg. for the most extreme case. The standard deviation in amplitude scaling was calculated to be less than 0.06 for all channels in the array. The performance of the calibration is evaluated …

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Anomaly Detection In Multi-Seasonal Time Series Data, Ashton Taylor Williams Jan 2023

Anomaly Detection In Multi-Seasonal Time Series Data, Ashton Taylor Williams

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Most of today’s time series data contain anomalies and multiple seasonalities, and accurate anomaly detection in these data is critical to almost any type of business. However, most mainstream forecasting models used for anomaly detection can only incorporate one or no seasonal component into their forecasts and cannot capture every known seasonal pattern in time series data. In this thesis, we propose a new multi-seasonal forecasting model for anomaly detection in time series data that extends the popular Seasonal Autoregressive Integrated Moving Average (SARIMA) model. Our model, named multi-SARIMA, utilizes a time series dataset’s multiple pre-determined seasonal trends to increase …

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Comparative Study Of Mof's In Phosphate Adsorption, Eniya Karunamurthy Jan 2023

Comparative Study Of Mof's In Phosphate Adsorption, Eniya Karunamurthy

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High concentrations of phosphate are known to adversely affect the environment. Excess phosphate can lead to eutrophication that eventually fosters uncontrollable growth of aquatic plants and algae. This can result in depletion of oxygen content which adversely impacts underwater organism’s survival rates. Metal organic frameworks (MOFs) consist of organic linkers in conjunction with metal ions or clusters arranged within a crystalline structure. They are highly porous and have larger surface area due to their ability to possess extensive void spaces while remaining bulky in nature. MOFs can absorb phosphate from aqueous solutions. We have investigated the use of commercially available …

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Path-Safe: Enabling Dynamic Mandatory Access Controls Using Security Tokens, James P. Maclennan Jan 2023

Path-Safe: Enabling Dynamic Mandatory Access Controls Using Security Tokens, James P. Maclennan

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Deploying Mandatory Access Controls (MAC) is a popular way to provide host protection against malware. Unfortunately, current implementations lack the flexibility to adapt to emergent malware threats and are known for being difficult to configure. A core tenet of MAC security systems is that the policies they are deployed with are immutable from the host while they are active. This work looks at deploying a MAC system that leverages using encrypted security tokens to allow for redeploying policy configurations in real-time without the need to stop a running process. This is instrumental in developing an adaptive framework for security systems …

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Characterization Of Aerosol Jet Printed Silver Thin Films Sintered By A Scanning Laser, William A. Metzger Jan 2023

Characterization Of Aerosol Jet Printed Silver Thin Films Sintered By A Scanning Laser, William A. Metzger

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Direct write printing, which is part of additive manufacturing (AM) technology, offers unique capabilities that can complement traditional methods of electronics fabrication. Printing of electrical interconnects via aerosolization is one of the areas in AM that is very important in electronics fabrication. Post-print sintering is a critical step in printed electrical interconnects because it strongly influences the electrical resistivity of the interconnects. Interconnects require the lowest possible resistivity to achieve better performance. Thermal sintering is the most common technique employed in printed interconnects. However, it is limited to substrates that can handle the high temperature requirement for sintering. For polymers …

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Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green Jan 2023

Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green

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Simultaneous Localization and Mapping (SLAM) is the process of using distance measurements to points in the surrounding environment to build a digital map and perform localization. It has been observed that featureless environments like tunnels or straight hallways will cause positioning faults in SLAM. This research investigates the fault diagnosis and accommodation problem for a laser-rangefinder-based SLAM systems on a quadrotor. A potential solution of using optical flow as velocity estimate and an extended Kalman filter (EKF) to perform position estimation is proposed. A fault diagnosis method for detecting faults in positional SLAM data or optical flow velocity data is …

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Digital Beamforming Array Phase Calibration Techniques For Multi-Pass Interferometric Sar, Kelly Cheung Jan 2023

Digital Beamforming Array Phase Calibration Techniques For Multi-Pass Interferometric Sar, Kelly Cheung

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Calibration plays a critical role in the optimal performance of algorithms in digital beamforming arrays. Phase incoherency between elements results in poor beamforming with decreased gain and higher sidelobes, leading to a decrease in accuracy and sensitivity of measurements. A similar problem exists in performing multi-pass interferometric SAR (IFSAR) processing of SAR data stacks to generate topological maps of the scene, where phase errors translate to height errors. By treating each SAR image in the data stack like an element of a uniform linear array, this thesis explores several phase calibration techniques that can be used to calibrate digital beamforming …

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A Machine Learning Framework For Hypersonic Vehicle Design Exploration, Atticus Beachy Jan 2023

A Machine Learning Framework For Hypersonic Vehicle Design Exploration, Atticus Beachy

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The design of Hypersonic Vehicles (HVs) requires meeting multiple unconventional and often conflicting design requirements in a hostile, high-energy environment. The most fundamental difference between ordinary aerospace design and hypersonic flight is that the extreme conditions of hypersonic flight require parts to perform multiple functions and be tightly integrated, resulting in significant coupled effects. Critical couplings among the disciplines of aerodynamics, structures, propulsion, and thermodynamics must be investigated in the early stages of design exploration to reduce the risk of requiring major design changes and cost overruns later. In addition, due to a lack of validated test data within the …

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Data-Driven Strategies For Disease Management In Patients Admitted For Heart Failure, Ankita Agarwal Jan 2023

Data-Driven Strategies For Disease Management In Patients Admitted For Heart Failure, Ankita Agarwal

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Heart failure is a syndrome which effects a patient’s quality of life adversely. It can be caused by different underlying conditions or abnormalities and involves both cardiovascular and non-cardiovascular comorbidities. Heart failure cannot be cured but a patient’s quality of life can be improved by effective treatment through medicines and surgery, and lifestyle management. As effective treatment of heart failure incurs cost for the patients and resource allocation for the hospitals, predicting length of stay of these patients during each hospitalization becomes important. Heart failure can be classified into two types: left sided heart failure and right sided heart failure. …

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Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal Jan 2023

Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal

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Since their invention in 1958, Integrated Circuits (ICs) have become increasingly more complex, sophisticated, and useful. As a result, they have worked their way into every aspect of our lives, for example: personal electronic devices, wearable electronics, biomedical sensors, autonomous driving cars, military and defense applications, and artificial intelligence, to name some areas of applications. These examples represent both collectively, and sometimes individually, multi-trillion-dollar markets. However, further development of ICs has been predicted to encounter a performance bottleneck as the mainstream silicon industry, approaches its physical limits. The state-of-the-art of today’s ICs technology will be soon below 3nm. At such …

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Investigation Of Surface Roughness Effects On Additively Manufactured Metals Under Dynamic Loading, Rachel Elizabeth Tullis Jan 2023

Investigation Of Surface Roughness Effects On Additively Manufactured Metals Under Dynamic Loading, Rachel Elizabeth Tullis

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The as-printed surfaces of parts produced through laser powder bed fusion are significantly rougher than surfaces produced through traditional manufacturing processes. This increased roughness can have a significant impact on mechanical properties, with perhaps the most notable detriment in the fatigue life of the part. Therefore, the as-printed surface roughness in additively manufactured materials must be studied more extensively to determine its impact on fatigue performance. This work investigates the surface roughness of additively manufactured specimens through the investigation of processing parameters and their effects on surface roughness in metal additive manufacturing. Furthermore, the relationships between as-printed surface roughness and …

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Kv2.1 Dysfunction Underlies The Onset Of Symptoms In Sod1-G93a Mouse Model Of Als, Andrew J. Deutsch Jan 2023

Kv2.1 Dysfunction Underlies The Onset Of Symptoms In Sod1-G93a Mouse Model Of Als, Andrew J. Deutsch

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Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease which targets motoneurons (MNs), yet underlying disease mechanisms are not well understood. Evaluating the intrinsic excitability of MNs in ALS could lead to a better understanding of mechanisms causing neurodegeneration. The SOD1-G93A (SOD) model is the most commonly studied animal model of ALS. However, past studies have shown highly conflicting results on SOD MN excitability. Interestingly, I show that depending on the level of membrane depolarization, SOD MNs show opposite results of both hyper- and hypo-excitability. This reveals that differences in the methodology of measuring excitability can heavily impact the study results. …

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Lipin1 Improves Membrane Integrity In Dystrophic Muscles Of Mdx Mice, Abdulrahman Jama Jan 2023

Lipin1 Improves Membrane Integrity In Dystrophic Muscles Of Mdx Mice, Abdulrahman Jama

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Duchenne muscular dystrophy (DMD) is an X-linked genetic disorder that affects 1 in 3500 male births worldwide. It is characterized by mutations in the dystrophin gene that results in the loss of functional dystrophin. Dystrophin deficiency leads to instability of the sarcolemma alongside increased inflammation, necrosis and fibrosis resulting in membrane rupture and eventual muscle fiber death. There are currently no effective treatments for DMD. Here we show that Lipin1 expression is significantly downregulated at the mRNA and protein levels in gastrocnemius muscle of mdx mice, the DMD mouse model. Lipin1 has a dual function as a phosphatidic acid phosphatase …

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Dna Instability At (Attct) Microsatellites In Human Cells, Venicia Alhawach Jan 2023

Dna Instability At (Attct) Microsatellites In Human Cells, Venicia Alhawach

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Microsatellites are short tandem repeats of DNA (1-9 nucleotides) that are unstable in the genome. They can expand and contract which leads to mutations and rearrangements that jeopardize genomic integrity. When encountered by a replication fork, repeats of these microsatellites can form non-B DNA structures which cause replication forks to stall and collapse eventually leading to double stranded breaks (DSBs) and replication stress. One form of repair of replication dependent DSBs happens via break induced replication (BIR), a highly mutagenic repair pathway. The main objective of this study is to understand how ATTCT pentanucleotide repeats affect replication and chromosomal instability …

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Understanding And Enhancing The Efficiency And Efficacy Of Machine Learning-Assisted Software Vulnerability Detection, Daniel J. Grahn Jan 2023

Understanding And Enhancing The Efficiency And Efficacy Of Machine Learning-Assisted Software Vulnerability Detection, Daniel J. Grahn

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As our world has become dependent upon software for nearly every aspect of modern society, software security has followed as an essential feature. The first line of defense against vulnerabilities is secure coding. While today’s programmers are carefully taught secure coding best practices, they can make mistakes or intentionally introduce vulnerable code. The traditional backstop to human errors and insider threats is the adoption of automated security analysis tools. These analysis tools have limitations. Static analysis suffers from high false positive rates that may cause annoyance and complacency among developers. Dynamic analysis can be difficult to set up and very …

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Microsatellite Induced Genomic Instability And Mutagenesis Through Break Induced Replication, Rujuta Yashodhan Gadgil Jan 2023

Microsatellite Induced Genomic Instability And Mutagenesis Through Break Induced Replication, Rujuta Yashodhan Gadgil

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Faithful DNA replication is essential to maintain genomic integrity. Compromises in this process are among the prime causes of cancer and other genetic disorders. Among several factors that can interfere with error-free DNA replication, the formation of non-B DNA structures by microsatellite sequences is critical. Microsatellites are 1-9 bp long tandem repetitive regions that can form secondary structures like hairpins, triplex, Gquadruplex etc. and undergo expansions due to replication fork stalling to cause several diseases. Hairpin forming microsatellites have been shown to induce DNA DSBs and lead to genetic instability and mutagenesis. The goal of this study is to understand …

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Simplified Mass And Inertial Estimates For Aircraft With Components Of Constant Density, Benjamin C. Moulton, Douglas F. Hunsaker Jan 2023

Simplified Mass And Inertial Estimates For Aircraft With Components Of Constant Density, Benjamin C. Moulton, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

Aircraft mass and inertial properties are required for predicting the dynamics and handling qualities of aircraft. However, such properties can be difficult to estimate since these depend on the external shape and internal structure, systems, and mass distributions within the airframe. Mass and inertial properties of aircraft are often predicted using computer-aided design software, or measured using various experimental techniques. The present paper presents a method for quickly predicting the mass and inertial properties of complete aircraft consisting of components of constant density. Although the assumption of constant density may appear limiting, the method presented in this paper can be …

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Winter Dynamics Of Storm Water Management Ponds And Winter Tolerance In Three Aquatic Plant Species, Patrick Strzalkowski Jan 2023

Winter Dynamics Of Storm Water Management Ponds And Winter Tolerance In Three Aquatic Plant Species, Patrick Strzalkowski

Theses and Dissertations (Comprehensive)

The vast majority of the research into the performance of stormwater management ponds (SWMPs) has been performed in warm regions or during the warmer seasons in temperate regions. It is presumed that SWMPs are inactive in the winter as any potential stormwater is trapped in snow and ice. The main goal of this thesis was to test this presumption and to study the dynamics and performance of three SWMPs during the winter. Remote water level loggers were installed into the three SWMPs and daily grab samples from the influents and effluents were taken and analyzed for total phosphorus (TP), chloride, …

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Recruiting More U.S. Women Into Engineering Based On Stories From Morocco: A Qualitative Study, Soundouss Sassi Dec 2022

Recruiting More U.S. Women Into Engineering Based On Stories From Morocco: A Qualitative Study, Soundouss Sassi

Theses and Dissertations

The objective of this project is to examine the differences between Moroccan and American students with regards to the cultural influences that led them to pursue an engineering degree. Annually since 2015, a partnership between a university in Morocco and MSU allows senior engineering Moroccan students to study at MSU to obtain their graduate degree in aerospace or mechanical engineering. The roughly equal gender representation in most Moroccan cohorts prompted our research question: “How do students from Morocco and the United States describe the cultural reasons that factored into their choice to pursue an engineering degree?” This exploratory qualitative study …

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2022 Fall Engr333 Project Section A Final Report, Dat Cao, Sam Hoover, Sawyer Masselink, Ian Vanderkooi, Matthew Carlson, Jacob Heeres, Anthony Nykamp, Jacob Wyngarden, Nate Anderson, Anna Giboney, Gia Mien Le, Jonathan Washburn, Jess Camp, Aubree Peters, Alin Stoica, Drew Stoneburner, Claire Sheppard, Alayna Spiering, Reid Veneman, James Viel Dec 2022

2022 Fall Engr333 Project Section A Final Report, Dat Cao, Sam Hoover, Sawyer Masselink, Ian Vanderkooi, Matthew Carlson, Jacob Heeres, Anthony Nykamp, Jacob Wyngarden, Nate Anderson, Anna Giboney, Gia Mien Le, Jonathan Washburn, Jess Camp, Aubree Peters, Alin Stoica, Drew Stoneburner, Claire Sheppard, Alayna Spiering, Reid Veneman, James Viel

ENGR 333

Calvin University has committed to being carbon neutral by 2057. This entails removing all the natural gas consumption for heating, converting to electrical heating options, and then making carbon free electricity. This project looked into four different options: air source heat pumps, ground source heat pumps, renewable natural gas, and the efficiency of current equipment. Each option was examined throughout the course of the semester to determine feasibility of each solution, and which ones would be best to implement. As a class, section A decided ground source heat pumps along with thermostatic valves and the implementation of double pane windows …

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