Stander Symposium: School of Engineering

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  3.6 MVA Electric Aircraft Powertrain Development

  Xiaoyan Liu, Vafa Marzang, Haoran Meng

  An electric aircraft powertrain includes four parts: fuel cell power sources, DC-DC converters, DC-AC inverters, and loads. In this poster, the fuel cell provides 3.6 MVA (2.5MW) electricity energy, which is converted to the required electric energy form of the load using DC-DC and DC-AC converters. The fuel cell offers 600-900 volt DC voltage, which converts to a fixed 1000VDC, and subsequently, the DC form converts to the AC electricity form using the DC-AC inverter. The DC-AC inverter's design, including power module selection, is described based on power loss and thermal analysis. The power losses, including conduction and switching losses, are derived to find the inverter efficiency and the junction temperature. The junction temperature of the power module is analyzed based on the derived power losses and thermal resistance among the ambient temperature at the junction of the power module. Furthermore, thermal analysis is performed to assess the power module's temperature distribution and thermal management requirements under different operating conditions. The simulation results, obtained using MATLAB and PLECS software, validate the mathematical analysis and provide a comprehensive understanding of the system's behavior.

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  Advancing Sickle Cell Disease Management: Introducing a High-Throughput Test for Irreversibly Sickled Cells

  John-Paul Stefano Bugada

  Sickle cell disease is an inherited red blood cell disorder caused by abnormal hemoglobin in the cells. This hemoglobin causes the cells to temporarily become rigid and shaped like a “C” or sickle. Sickle cells can get stuck and block blood flow leading to pain, infections, and other serious complications. The percentage of irreversibly sickled cells (ISCs) is an indication of how patients are managing their sickle cell disease. Currently, the best way to quantify ISCs is to use a microscope to count the normal red blood cells and ISCs and then manually calculate a percentage. This method is both time-consuming and subjective, and as a result, it is not being used even though it can help doctors better understand how patients are managing their disease. Through my research at Cincinnati Children’s Hospital, we developed a high-throughput ISC test that is faster, more efficient, and more consistent than the current method. This new method uses machine learning analysis software to sort through tens of thousands of pictures of cells from a patient and determine the percentage of ISCs. The new test correlates with the current method without having to train people to recognize sickle cells or manually count them. We believe that this test will provide more accessible, accurate, and consistent monitoring of sickle cell disease while reducing subjectivity, costs, and time.

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  Analysis and Design of High-Efficiency Modular Multilevel Resonant DC-DC Converter

  Haoran Meng

  This paper demonstrates a high-efficiency modular multilevel resonant DC-DC converter(MMRC) with zero-voltage switching (ZVS) capability. In order to minimize the conduction loss in theconverter, optimizing the root-mean-square (RMS) current flowing through switching devices is consideredan effective approach. The analysis of circuit configuration and operating principle show that the RMSvalue of the current flowing through switching devices is closely related to the factors such as the resonanttank parameters, switching frequency, converter output voltage and current, etc. A quantitative analysis thatconsiders all these factors has been performed to evaluate the RMS current of all the components in thecircuit. When the circuit parameters are carefully designed, the switch current waveform can be close tothe square waveform, which has a low RMS value and results in low conduction loss. And a design examplebased on the theoretical analysis is presented to show the design procedures of the presented converter. A 600W48 V-to-12 V prototype is built with the parameters obtained from the design example section. Simulationand experiments have been performed to verify the high-efficiency feature of the designed converter. Themeasured converter peak efficiency reaches 99.55% when it operates at 200 kHz. And its power density canbe as high as 795 W/in3.

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  Analysis of benefits in consolidation for vehicle routing problems with time windows

  Nikesh Chithambaram

  Vehicle routing is a complex optimization problem with different variations. In this study, we focus on evaluating the advantages of consolidation for vehicle routing problems with time windows. With the help of Google OR tools and deep reinforcement learning solutions, we aim to analyze and compare the benefits of consolidation under different parameters and evaluate the performance of both for increasing number of orders and customers. Our approach involves consolidating orders within specified windows as customers place multiple orders if they fall within a consolidation window based on next day delivery plan. Through this research, we seek to provide insights into the optimal methods for managing vehicle routing logistics in scenarios where consolidation plays a pivotal role.

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  Analysis of Power System Resilience Subject to Extreme Events

  Adedayo Joshua Aruwajoye

  This study aims to increase the understanding of power system resilience through pattern recognition of disaster induced system disruption. This study consists of analyzing power system failure and recovery patterns in a post extreme event environment to determine relevant pattern characteristics relating to power system resilience in statistical terms. Specifically, the methodology of this progressive study consists of (1) collecting and processing data from power system failures induced by natural disasters categorized by power companies, states, counties, and natural disaster occurrence, (2) developing failure and recovery curves for the collected data, (3) investigating and establishing a distribution model that correlates to the goodness of fit for plotted curves best characterizing the system behavior for each extreme external occurrence, and (4) creating an algorithm for specifying the resilience of such engineered systems. This study will then explore the resultant algorithm in modelling and answering questions about the resiliency of power systems subjected to some extreme events first, opening extensions to other kinds of natural disasters in the future. Since modern society relies extensively on power systems to survive, this increased insight into power system resilience will provide better situational awareness for stakeholders during future decision-making discussions regarding power system construction.

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  A Numerical Study on the Effects of Varying Types and Spacing of Reinforcement Elements in Mechanically Stabilized Earth Walls (MSEW)

  Jonathan Lawrence Gardner

  Mechanically stabilized earth walls (MSEWs) are an increasingly popular type of retention structure being constructed in the United States. According to the Federal Highway Association, it is estimated that over 9,000,000 square feet of MSEWs are constructed in the United States each year. These types of structures make use of a reinforced soil mass to support the retained soil or backfill. There are two primary categories of reinforcement used in mechanically stabilized earth walls: inextensible and extensible reinforcement. However, in each of these categories there are various types of reinforcement that can be utilized in the design. With all the available options for different kinds of reinforcement, it can be difficult for an engineer to determine the best type of reinforcement for a given project. The primary objectives of this project include: analyzing the effects of using various types of reinforcement on computing the required length to satisfy internal stability requirements in MSE walls, studying the effects of changing the spacing of reinforcement elements when performing internal stability analysis, studying the effects of total wall height when performing internal stability analysis, and evaluating the potential for over-design and under-design along the height of the wall when using the initial design assumption that L=0.7H.

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  A Topology Optimization Results Spaceframe Interpreter for the Design of Lightweight Aircraft Structures

  Jack Anthony Studnicka

  This poster presents the methodology and theoretical foundation of topology optimization (TO) Results Spaceframe Interpreter, an automatic TO results interpreter that generates a closely associated space frame consisting of welded structural tubing or rectangular bars. TO is a computational technique that uses a finite element (FE) formulation to identify the most weight-efficient structure within a design domain. Density-based TO results in structures that take organic forms and is usually a tedious and cumbersome process to generate a computer-aided-design (CAD) model to manufacture through conventional techniques. The optimal topology frequentlyresembles a space frame, which is well-known as being a rigid, lightweight structure. The methodology of the TO results interpreter leverages several techniques from volumetric image processing and has four primary processes. First, the results are obtained from commercial FE/TO software and mapped into a cubic grid of voxels. Second, junction locations are extracted and member connectivity that represents a frame is identified. Third, a sizing optimization is incorporated to determine appropriate sectional dimensions of the circular or rectangular space frame members. Fourth, the optimized space frame geometry is imported into a CAD design tool to automatically create a design model. The automated TO interpreter is designed to interact with commercial FE analysis and CAD systems. The interpreter is demonstrated on various spatial examples including aerospace and automotive applications. In each case, the welded space frame closely resembles the TO result, with nearly equivalent stiffness and mass.

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  Beyond Technology: Social Predictors of Energy Efficiency in Industrial Facilities

  Garret B. Cowdery

  Energy is the lifeblood of the industrialized world with electrical energy expected by the National Renewable Energy Laboratory (NREL) to increase 25% between 2016 to 2050 in the United States. Combined with the ever-present climate crisis, energy-efficient buildings are becoming increasingly important to conserve resources and alleviate strain on aging energy systems. The Industrial Assessment Center (IAC) program through the US Department of Energy aims to reduce the consumption of large, single-site energy users, industrial and commercial buildings, through comprehensive energy audits. Such investigations find that energy-efficient structures are a technological challenge as much as social. The mentality of building occupants towards energy use strongly impacts the efficiency of the building with the energy conscientiousness of the inhabitants being a key factor in maximizing theoretical performance. Not in My Backyard (NIMBY) is a social phenomenon where communities rise in opposition to controversial facilities that serve to upset community wellbeing. These are generally energy-intensive projects that may detract from the natural beauty or environmental health of an area. The negative reaction originates from difficult-to-measure factors such as personal attitudes and trust between involved parties but can be loosely predicted by specific demographic quantities. This investigation aimed to primarily analyze the quantity, scale, and quality of community energy systems at the county level of Ohio in conjunction with collected IAC data and NIMBY demographics to identify potential external predictors for industrial energy intensity based on NIMBY sensitivity. Ultimately, only a weak correlation is found between industrial facility energy usage and the listed attributes, but the investigation paints a vivid demography of people, energy resources, and industrial agglomeration while emphasizing and supporting the need for continual research into the social functions that drive technical success.

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  Characterizing the Broadband Frequency Response of Pressure-Sensitive Paint

  Charles Jerome Strunc

  Pressure-Sensitive Paint (PSP) is an exceptional tool used to gather the pressure distribution on a model during a wind tunnel test (or other similar methods of testing) in the form of a high-resolution image. In order to use the PSP effectively, however, an intimate understanding of the paint being employed must first be established and the reaction time of the paint being developed must be pushed to the limit. These goals in my work are accomplished by sending various novel PSP creations through a resonance tube that was designed, constructed, and applied here on campus. The resonant qualities of an air column in the tube are exploited to increase the magnitude of the rapid pressure fluctuations coming from a speaker system. The pressure readings from the paint inside the tube will be compared to the more exact results from a pressure transducer to determine the frequency response time of the paint, thus allowing the testing of novel PSP at any desired frequency range between 0 and 60 kHz.

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  Designing Spherical Mechanisms, from Wrist Orthotics to Mechanical Novelties

  John Gordon Hoover, Franklin Alexander McClimans

  This research explores a spherical mechanism designed as a component in a wrist orthotic. A spherical mechanism, a little used class of mechanical device, allows the limitations commonly associated with conventional wrist orthoses to be effectively addressed. With a theoretical model of the wrist orthotic and its component spherical mechanism developed in previous work, several questions remain. These questions include addressing the mechanical design issues to realize a working orthotic prototype, and exploring the spherical mechanism fundamental to the orthotic to explore its unique properties. The spherical mechanism is classified as a drag-link device, meaning it is capable of large motions of many of its component links. To take advantage of these large motions, several design considerations need to be addressed by this work.

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  Design of Smart Magnetic Beads for Water Purification

  Adam J. Jones, Levente Istvan Karetka

  New technologies are needed to advance current state-of-the-art water purification processes. Sodium alginate, a bio-based polymer made from brown seaweed, is a promising material for this application. Current studies using this biopolymer include applications in water treatment, drug delivery, and food engineering. Over the last two semesters, undergraduate students have explored this polymer along with magnetic nanomaterials in the Nanoscale Engineered Materials Laboratory (NEMLab) at UD as part of their Ethos R&D course. The students not only performed technical research but also participated in outreach activities, including in-person and video demonstrations with the Boonshoft Museum of Discovery. In the NEMLab, students are actively participating in research involving the preparation of magnetic sodium alginate gels and beads, performing viscosity and rheological studies of various concentrations and dispersions.

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  Design Space Exploration for a Novel Self-Healing Elastomer, Informed by Bayesian Optimization

  Robert M. Drexler

  Self-healing elastomers are an emerging class of materials capable of mitigating vulnerability to externally-induced damage. Recent advancements in polymer chemistry have led to self-healing elastomers that are 3D-printable, exhibit real-time self-healing in the absence of external stimuli (e.g., heat, light), and use commercially available (COTS) precursors to enable production at scale. However, at present, the trade-offs between virgin mechanical properties and self-healing efficiency are not well known. To address this research opportunity, this talk presents an experimental program – informed by a Bayesian optimization platform – to (a) facilitate design space exploration and (b) investigate the interplay between virgin mechanical properties (i.e., hardness and toughness) and self-healing efficiency (e.g., ratio of healed toughness to virgin toughness) as chemical composition is varied. The material of interest is BeckOHflex, a new acrylate/thiol-ene elastomer that exhibits real-time, autonomous self-healing and is exclusively prepared from COTS precursors. The experimental design was conducted by varying the crosslinker and thiol components from 0-10% by volume while holding the molar ratio of acrylate and photoinitiator constant. Test samples were cast in custom silicone molds and cured using an external UV lamp. Hardness data was obtained using an analog Shore OO durometer, and mechanical property data was collected through uniaxial tension testing. Informed by previous-iteration experimental inputs (chemical composition) and the resulting outputs from mechanical testing (virgin hardness, virgin toughness, and self-healing efficiency), a Bayesian optimization platform (EBDO+) was used to suggest next-iteration experimental inputs. Through this iterative process of synthesizing, testing, and analyzing different compositions throughout the experimental campaign, a well-defined Pareto frontier will be determined to bound the design space, allowing for a fundamental, quantitative understanding of tradeoffs between virgin mechanical properties and self-healing efficiency. It is expected that the Pareto frontier will be determined after tens of experiments out of a possible 2,000+ discrete input parameter combinations.

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  Development of a Machine Learning-Based Program to Measure Cell Proliferation

  Adam J. Jones

  Many tools have emerged to investigate the functioning of biological systems, especially when in contact with foreign substances. In vitro procedures are often used due to their cost effectiveness and suitability for high-throughput experiments. These procedures collect basic measurements, such as toxicity and biocompatibility, that provide insight into the compatibility and safety of a substance.In vitro toxicity tests are favored for their expediency, affordability, and consistent outcomes. Quantitative methodologies, like colorimetric and fluorometric assays, offer objectivity and high-throughput analysis. However, they require lengthy incubation times and only provide a single metric. Microscopy-based methods provide more information in terms of cell morphology and localization, and can be captured quickly without the need for reagents and incubation. Yet, this method requires specialized expertise and is prone to subjective biases and variations based on the region-of-interest.Given the limitations of microscopy-based approaches, there is a growing interest in leveraging machine learning (ML) to streamline and enhance cell analysis. This study aims to develop an ML-based approach to evaluate cell count and confluency from microscope images and compare its performance to the colorimetric assay, CCK8. The CCK8 assay, which releases a dye when metabolized by live cells, served as the benchmark for comparison. The ML-based method, developed using Ilastik, CellProfiler, and Python, segments microscopy images into cell and background regions, followed by erosion for cell boundary enhancement. CellProfiler subsequently quantifies the cell count and confluency from the processed images.This novel ML-based approach offers expedited analysis, while mitigating the inherent subjectivity and error associated with conventional techniques. This approach also eliminates the need for excess reagents and waste associated with quantitative assays. In conclusion, this technique presents an alternative in scenarios where traditional assays are impractical, such as with low cell counts or when cells must be reused.

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  Development of an optical technique for microplastic detection in water

  Geoffrey Scott Campman

  In the last ten years, microplastic pollution has become a very salient problem in large bodies of water such as lakes or oceans. Therefore, study of pollution of that sort has become an area of interest for oceanographers and physicists alike. Present-day collection, detection, quantification, and analysis techniques are time-intensive, complex, and lack standardized procedures. One of the main drawbacks is that the water sample is collected and taken back to the lab for further processing and analysis, often using a form of microscopy. This all makes it difficult to observe the temporal behavior of the amount of microplastics present at a certain location. The use of laser beam propagation in the ocean for detection purposes has been studied in recent years. A novel pollution detection method for microplastics has been developed, which records laser-light scattering induced by said microplastics at multiple angles. A camera is added to the setup, which will be able to give an estimate of the size and shape of the microplastics. Measurements were performed in a laboratory setting using two types of microplastics; PET and PLA. The results showed that correlations between outlier scattering readings and average power of scattering can be used to determine the composition of plastic in a body of water. Furthermore, we believe that this method of detection has the added advantage of providing temporal measurements, as it can be performed in-situ and over a long(er) period of time. This could provide a more accurate understanding of the temporal behavior of the concentration of microplastics in a body of water.

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  Doors, Trikes and Folding Wings: Advancing Concepts for Machines Using MotionGen

  Andrew William Gasser, Veronica Michele Hatfield, Brian Andrew Piper, Brock Robert Smith

  MotionGen, a kinematic analysis and synthesis tool, helps to readily develop working kinematic models of mechanisms, planar robotic systems, and heavy machinery like backhoes and bulldozers. By using MotionGen, these systems can be readily synthesized and animated. A team of DIMLab (Design of Innovative Machines Lab) students has been busy this semester learning MotionGen and using it to create novel yet practical designs. We have utilized MotionGen to model recumbent tricycles for people with disabilities who pedal with FES, to investigate novel architectures for mechanical presses, to ideate on a novel swinging door, and to assess the motion of a foldable airplane wing.

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  Effect of Si/Al Ratio on the Transport Behavior of Zeolitic Nanotubes.

  Muhammad Rizwan

  Carbon nanotubes are the poster child of 1-dimensional nanomaterials, but in recent years attention has spread to other chemistries such as boron-nitride and molybdenum-disulfide. The first nanotubes with zeolitic walls were recently synthesized. This new structure presents both nanoscale pores in the nanotube wall and a mesoscopic channel along the tube axis. These molecular structures have the potential to be impactful in several applications, but a fundamental understanding of how their new structure affects their adsorption and transport properties is critical to realizing their widespread use. We use molecular dynamics simulations to investigate the effect of Si/Al ratio and the associated charge defects on the adsorption and transport of different liquids within the multiscale features of the zeolite nanotube.

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  Enhancing Deep Collaboration through Experiential Learning: The Impact of the Stitt Scholars Program

  Avery Lorraine Baltrus, Trent Edward Borgmann, Anna Isabella Carollo, Lauren E. Carr, Austin M. Ebbing, Brooke Elisabeth Hunstad, Brian Nicholas LeCocq, Loring L. Leitzel, Lucianna T. Nice, Kevin Louis Nudo, John Protz, Yadiel Yomar Roque, Raegan Mae Rowland, Catherine Sayeedi, Erin O. Wagner, Jack Vincent Waters

  Collaboration in higher education has significantly improved, with programs increasingly incorporating collaborative elements in their curricula. Despite these advances, there is a pressing need to further enhance interdisciplinary collaborations through experiential learning. The Stitt Scholars Program exemplifies this by offering students from the School of Engineering, the College of Arts and Sciences, and the School of Business Administration opportunities to work with startup companies at the HUB, supported by PNC Bank. Students commit ten hours weekly to their projects and engage in lectures on innovation and entrepreneurship. The program's success has attracted further investment, enabling its expansion and continued contribution to interdisciplinary education and community engagement.

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  Ethos Guatemala Breakout - Aquaponic Systems

  Adam Robert Cartwright, Franklin Alexander McClimans, Sarah Jane McDonald, Keagan G. McDonough, Jacob D. Pentasuglio

  A team of undergraduate engineering students developed and installed an aquaponic system at a school for children from low income families in Zaragoza, Guatemala. The students used a systems thinking approach as part of a design thinking process for this project. During a 10-day immersion in Guatemala, they learned from and worked with local aquaponic experts and members of the community to install a system that is sustainable and appropriate for the school. This project is part of the Ethos Center within the UD School of Engineering.

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  Ethos Guatemala Breakout - Photovoltaic Systems

  Leah Michelle Dalton, Sophia Marie Dugan, Adriana Lucia Garcia, Amanda Metzler, Cameron A. Pierson

  A team of undergraduate engineering students developed and installed photovoltaic systems for low income families in El Jocotillo, Guatemala who did not have access to electricity. The students used a systems thinking approach as part of a design thinking process for this project. During a 10-day immersion in Guatemala, they learned from and worked with local photovoltaic experts and members of the community to install photovoltaic systems that are sustainable and appropriate for the families. This project is part of the Ethos Center within the UD School of Engineering.

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  Experimental Investigation of a Novel Morphing Wing Design

  Julian Alejandro Pabon

  The aerodynamic performance of a novel Fishbone Skin-Actuated-Camber (SAC) morphing wing design, which actuates its skin to change its effective camber, was studied both experimentally and numerically. Force-based experiments were conducted at the University of Dayton Low Speed Wind Tunnel (UD-LSWT) to compare the performance of four morphing wing designs with different hinge locations, two ideal trailing edge flap wings, and one conventional trailing edge flap wing. All test articles have an Eppler 479 airfoil, an effective aspect ratio of four, and were tested within an angle of attack range of -15° and 15 °. The novel design achieved effective camber change without any buckling, maintaining comparable aerodynamic performance to ideal flap wings at a Reynolds number of 270,000. At a Reynolds number of 400,000, the morphing shows a lower drag than the ideal flap wing. Simulations from FlightStream®, a numerical solver correlated well with experimental lift data, with the morphing wing's pressure contours indicating reduced flow separation and gradual pressure change on the upper surface when deflected.

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  Failure modes of silver versus gallium-alloy conductive traces at flex-to-stretch interfaces

  Josafat Jimenez

  Traces made from a conductive liquid-metal ink are blade coated onto a Thermoplastic Polyurethane (TPU) substrate for flexible and stretchable applications. The same process is used for a silver flake composite ink to compare with liquid-metal samples. Uniaxial strain is applied to the samples to test resistance response of 2 mm-wide traces for both inks to investigate electrical loss and failure modes. Results show 10x increase from initial resistance at strains of 15% for silver composite inks and 140% for liquid-metal inks on average. The failure mode of the silver composite is attributed to intrinsic material loss under strain while failure for liquid-metal inks is due to localized strain at the interface between TPU and polyimide. Bilayer traces with both inks exhibit both positive ink qualities, showing silver-like initial resistance and liquid-metal-like strain tolerance. Finally, using a softer substrate of styrene-ethylene-butylene-styrene (SEBS) demonstrates higher straintolerance than TPU, without plastic deformation and lower resting state resistance creep after cycling.

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  Fatigue Limiting Behavior of LPBF Parts (AM Process Improvement)

  Luke Lowell Weston

  This study investigates the fatigue limiting behavior in aerospace alloys, focusing on the role of Critical Resolved Shear Stress (CRSS) in determining fatigue limits. Initially targeting Ti-6Al-4V (Ti64) for four-point bending fatigue bars using Laser Powder Bed Fusion (LPBF), challenges with contaminated Ti64 powder led to a shift to martensitic 17-4PH stainless steel (17-4 stainless). The research explores the impact of CRSS on fatigue limits, emphasizing its importance over slip systems per Mlikota's findings. Surface roughness analysis of the 17-4 stainless bars revealed a consistently higher average roughness, sharpness of peaks and valleys, and most importantly depth of valleys on the as-built side compared to the cut side. xCT scanning showed a 99.02% density obtained from the “high quality” parameter set, which would be suitable for many structural applications. However, the ordered networks of pores along the hatching suggest that material from this parameter set could never be considered airworthy due to the high surface area to volume ratio/surface energy. The manufacturers "normal" parameter set yielded 99.99% dense bars as measured by xCT, which is better than most castings.This research contributes to the understanding of the importance of CRSS in aerospace structural design and the fatigue limiting behavior of aerospace-relevant alloys. The findings emphasize the need for further investigation into the relationship between CRSS, slip systems, and the design of materials with infinite fatigue lives. With a proper understanding of the influence of CRSS on fatigue limiting behavior, it may be possible to develop aerospace alloys with infinite fatigue lives, greatly lowering maintenance costs.

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  Fixed Wavelength Interferometer Sensors for Low-Cost Chem-Bio Sensing Applications

  Jianhao Shen

  We experimentally demonstrated slow wave enhanced phase and spectral sensitivity in asymmetric Michelson interferometer sensors with a phase sensitivity of 277,750 rad/RIU-cm and theoretical phase sensitivity as high as 461,810 rad/RIU-cm. In the context of low-cost chip integrated photonic packaged sensors, in this paper we will experimentally demonstrate a method for active tuning of interferometer fringes using phase change materials that will potentially overcome fabrication-induced variation of interference fringe wavelengths, thus allowing sensor chip packaging with a fixed wavelength laser and available integrated photodetectors.

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  Flight Test Validation of Tandem Propeller Performance with Vertical and Horizontal Offset

  Jessica Caitlyn DeMoor, Michael Ryan Foster

  Tandem propellers in forward flight experience an increase in power consumption when compared to the combined output of two standalone propellers. The increment in power is a function of horizontal and vertical displacement between the propellers (including overlap), the advance ratio based on the front rotor, and the inclination angle of the rotors. This functional relationship was quantified in our previous study through experimental investigations in the University of Dayton Low Speed Wind Tunnel using two KDE propellers. All tests were conducted under trim conditions, where the pitching moment of the two propellers was balanced by increasing the RPM of the rear rotor. To validate some of the functional dependencies identified from the wind tunnel investigations, a custom quad-rotor platform was designed and fabricated to conduct a series of flight tests with various propeller configurations that replicate the parameter space explored in the earlier experimental campaign. The quad-rotor platform will utilize an 8-inch propeller to assess the flight performance at three different horizontal and vertical distances between the propellers. For each test-flight, global positioning data, motor rpm, and motor power consumption will be recorded and compared against each propeller configuration. Comparisons between the flight test data and the wind tunnel experiment results will be made.

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  From Blue-Gray to Blue-Green: Facilitating the Transition to Non-Plastic, Natural Material Use within the Coastal Zone Economy

  David Albrecht, Caleb Luke Frank, Adin Allen Stoller

  Funded by NOAA and in collaboration with the Baruch Marine Field Institute, this project addresses the environmental impact of non-biodegradable plastics in coastal South Carolina. It explores the mechanical and economic viability of natural materials like coir, jute, and hemp to replace plastics in critical coastal sectors that experience harsh environmental conditions. The first class of products studied was natural fiber geotextiles due to their current prominence in coastal environments. Before studying the impacts of weathering on mechanical properties, the virgin, unweathered properties must be measured and the impact of water absorption on the mechanical properties must be understood. An Instron 3365 in the UD BAMS laboratory was utilized to perform tensile testing on virgin samples according to ASTM 6818 to assess key properties including strain, Young's modulus, and tensile strength, to determine how these materials will initially behave in harsh coastal environments. Additionally, qualitative observations of the materials’ mechanical response and failure were recorded to discuss and assess material viability with environmental engineering stakeholders in South Carolina. In conjunction with this testing, samples with different relative water absorption levels were tested to understand the impact of water content on the materials’ mechanical properties. An analysis of variance (ANOVA) was used to determine the effects of water content on mechanical properties. Future studies will examine how coastal weathering affects mechanical, chemical, and structural properties of these materials to qualify them for use in coastal sectors. This project, merging traditional ecological knowledge and modern engineering techniques, underscores the potential for a significant paradigm shift towards sustainable material usage in coastal ecosystems, aligning with broader objectives of environmental stewardship and culturalpreservation.