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Full-Text Articles in Engineering

Analysis And Reinforcement Measures For Unconventional Cracks In Gravity U‐Type Abutment, Cheng Kun, Du Yinguang, Liu Zhang May 2023

Analysis And Reinforcement Measures For Unconventional Cracks In Gravity U‐Type Abutment, Cheng Kun, Du Yinguang, Liu Zhang

Journal of China & Foreign Highway

Horizontal cracking at the foundation level is uncommon in gravity U-type abutments. This paper investigates the causes and reinforcement measures for unconventional horizontal cracks in the foundation and vertical cracks in the abutment wall of a gravity U-type abutment on a highway bridge. Survey and analysis results show that the vertical cracks in the abutment wall are structural cracks caused by excessive reaction forces from permanent loads combined with the impact loads from vehicles at expansion joints. The horizontal foundation cracks result from the presence of filler interlayers at the foundation, which softened over time due to water exposure, leading …

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Analysis On Vehicle‐Bridge Interaction Of High‐Pier Continuous Rigid Frame Bridge, Liu Huaquan, Yang Dehai, Cai Chengqi, Huang Zhenming, Chen Zhouqi May 2023

Analysis On Vehicle‐Bridge Interaction Of High‐Pier Continuous Rigid Frame Bridge, Liu Huaquan, Yang Dehai, Cai Chengqi, Huang Zhenming, Chen Zhouqi

Journal of China & Foreign Highway

To study the dynamic response characteristics of the vehicle-bridge system under moving vehicle loads, a three-span high-pier continuous rigid frame bridge was selected as the research object. A 2-axle, 7-degree-of-freedom vehicle model was applied to explore the effects of vehicle speed, number of vehicles, and vehicle load on the dynamic response of the vehicle-bridge system. The results show that vehicle speed has minimal impact on the peak displacement response of the bridge. However, when vehicles travel at the same speed, the peak displacement response differs across bridge spans, with resonance occurring at a vehicle speed of 40 km/h. As the …

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Research On Application Of Equivalent Stiffened Plate Elements In Local Stability Calculation Of U‐Shaped Stiffened Plates, Chen Xiangjun May 2023

Research On Application Of Equivalent Stiffened Plate Elements In Local Stability Calculation Of U‐Shaped Stiffened Plates, Chen Xiangjun

Journal of China & Foreign Highway

To address the issue of excessively large computational models in the numerical simulation of U-shaped stiffened plates in large-span flat steel box girder main girders, this paper proposes a finite element calculation theory using equivalent stiffened plate elements and a simplified method for U-shaped stiffened plates. By simplifying the U-shaped small box ribs in U-shaped stiffened plates into equivalent stiffening strips, the transverse stiffness of the cover plate is redistributed, and the effect of equivalent stiffeners on the stress of the plates is calculated. Stability analysis was conducted using Fortran language developed on the Ansys platform, and the results were …

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Optimization Research Of Laying Method And Material Type Selection Of Thermal Insulation Layer For Tunnels In Cold Region, Wu Tao, Liu Zhichun, Liu Xuejiao, Zhang Hongfei May 2023

Optimization Research Of Laying Method And Material Type Selection Of Thermal Insulation Layer For Tunnels In Cold Region, Wu Tao, Liu Zhichun, Liu Xuejiao, Zhang Hongfei

Journal of China & Foreign Highway

To address the issue of frost damage in tunnels in cold regions, research on thermal insulation and frost prevention is crucial. This paper utilizes an improved analytic hierarchy process combined with grey relational analysis to identify optimal insulation materials suitable for different laying methods that provide effective insulation. Numerical simulation methods were then used to calculate and analyze the tunnel temperature field under various combinations of insulation materials and laying methods. Based on the “composite temperature field” comparison results, the optimal insulation scheme was determined. The results show that the “off-wall laying + Furritek insulation board” combination is the optimal …

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Experimental Study On Influence Of Phosphorus Slag Powder On Pervious Concrete, Lou Jianxin, Yang Jianyong, Zhang Yuxian, Li Jun, Wang Jie, Liu Jian May 2023

Experimental Study On Influence Of Phosphorus Slag Powder On Pervious Concrete, Lou Jianxin, Yang Jianyong, Zhang Yuxian, Li Jun, Wang Jie, Liu Jian

Journal of China & Foreign Highway

This paper investigates the effects of replacing cement with phosphorus slag powder on the mechanical properties, permeability, and pavement performance of pervious concrete. The results show that incorporating a certain amount of phosphorus slag powder as a partial replacement for cement in pervious concrete is feasible. When the replacement ratio of phosphorus slag powder is within 10%, it enhances the strength of pervious concrete. The optimal replacement ratio of phosphorus slag powder is 8%, achieving a compressive strength of 24.18 MPa, a void ratio of 15.37%, and a permeability coefficient of 2.45 mm/s, which meet the requirements for fully permeable …

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Dynamic Load Response Analysis Of Rubber Powder Modified Asphalt Mixture, Yang Sanqiang, Sun Shuang, Li Qian, Liu Xinlei, Qin Lusheng May 2023

Dynamic Load Response Analysis Of Rubber Powder Modified Asphalt Mixture, Yang Sanqiang, Sun Shuang, Li Qian, Liu Xinlei, Qin Lusheng

Journal of China & Foreign Highway

To investigate the mechanical response of rubber powder modified asphalt pavement under dynamic loads, this paper, based on the “Full-Scale Accelerated Pavement Loading Testing” project, designed experimental schemes for asphalt mixtures with varying rubber powder contents. The paper employed accelerated loading test equipment to evaluate the stress and deformation of pavement structures, obtaining dynamic strain response data to analyze the strain response patterns of various structural layers. Combining finite element numerical simulations and a custom loading program, the paper examined the dynamic responses of rubber powder modified asphalt pavements under variable temperature conditions. The results show that through microscopic testing, …

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Aging Asphalt Concrete Cracking Performance Under Different Cyclic Loading Frequencies, Yan Jingchen, Ma Yanpei, Yan Junjie May 2023

Aging Asphalt Concrete Cracking Performance Under Different Cyclic Loading Frequencies, Yan Jingchen, Ma Yanpei, Yan Junjie

Journal of China & Foreign Highway

Using digital speckle technology, this paper examines the crack propagation behavior of asphalt concrete under repeated loading, analyzing the crack propagation mechanism from macro- and micro-perspectives under different aging conditions and loading frequencies for four types of asphalt concrete. The results show that the basalt fiber-reinforced asphalt concrete beam specimens delay the onset of the unstable crack propagation phase, thus extending the service life of the asphalt concrete. Aging accelerates the progression of asphalt concrete to the unstable crack propagation point, advancing this stage by 4%-5%. Under repeated loading frequencies of 5 Hz, 10 Hz, and 15 Hz, the damage …

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Design And Development Of Two And Three Dimensional Integration System For Highway Based On Webgis, Che Defu, Zhou Huajun May 2023

Design And Development Of Two And Three Dimensional Integration System For Highway Based On Webgis, Che Defu, Zhou Huajun

Journal of China & Foreign Highway

To address the inefficiencies, lengthy cycles, and high resource demands in the process of determining the annual project database for highway maintenance quotas in Liaoning Province, a 2D and 3D integration system for highways based on WebGIS was designed and developed. This system not only provides a macroscopic view of the geographic distribution and overall characteristics of highways but also offers a detailed and intuitive representation of the spatial relationships and conditions of roadbeds and pavement damage. The system meets the needs of modern highway management and can serve as a reference for other highway maintenance quota tasks.

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Study On Relationship Of Solar Radiation Temperature And Pier‐Top Displacement Of Ultra‐High Thin‐Walled Hollow Pier, Liu Zhishen, Zhang Yifei, Song Fei, Su Jufeng, Ren Xiang May 2023

Study On Relationship Of Solar Radiation Temperature And Pier‐Top Displacement Of Ultra‐High Thin‐Walled Hollow Pier, Liu Zhishen, Zhang Yifei, Song Fei, Su Jufeng, Ren Xiang

Journal of China & Foreign Highway

Thin-walled hollow piers are widely used in high-pier and long-span continuous rigid-frame bridges. Solar radiation-induced displacements at the tops of ultra-high thin-walled hollow piers can negatively affect the structural alignment and stress during construction and post-construction phases. Based on a 180 m high thin-walled hollow pier of a large bridge in Shaanxi Province, this paper analyzes the temperature field and pier-top displacement using data collected during two 24-hour periods: August 28-29 and October 11-12. The temperature field and pier-top displacement patterns over time were studied using finite element analysis. The results show that the temperature difference between the north and …

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Model Test Study On Mechanical Characteristics Of Spherical Joints In Multi‐Point Support Swivel System, Zeng Lifei May 2023

Model Test Study On Mechanical Characteristics Of Spherical Joints In Multi‐Point Support Swivel System, Zeng Lifei

Journal of China & Foreign Highway

As a critical load-bearing component in bridge swivel systems, the mechanical behavior of spherical joints is essential for the safety of bridge swiveling operations. This study focuses on the spherical joints of a multi-point support swivel system for the bridge over the Xiangyang North Marshalling Yard. Model tests were conducted to analyze the effects of the number of supporting legs, swivel speed, track smoothness, and wind load on the stress of spherical joints. The stress variation patterns of spherical joints under different working conditions were investigated. The results show that increasing the number of supporting legs improves the uniformity of …

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Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng May 2023

Selection Of Phase Change Materials For Asphalt Pavement Based On Molecular Dynamics Simulation, Liu Fujun, Tian Xin, Liang Meichen, Guo Meng

Journal of China & Foreign Highway

Phase change materials (PCMs) have significant application potential in temperature regulation for asphalt pavements. To select suitable PCMs for road applications, this paper utilizes molecular dynamics simulation to analyze the molecular behaviors of lauric acid and polyethylene glycol (PEG). Experimental studies were conducted to validate the simulation results. The results show that molecular dynamics simulation provides an efficient and convenient method for comparing the performance of PCMs. PEG outperforms lauric acid in terms of molecular density, cohesive energy density, solubility parameters, and thermal conductivity, making it more suitable as a phase change material for asphalt pavements.

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Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang May 2023

Study On Alkali Excitation Mechanism Of Large Dosage Slag Fine Powder, Mei Yang

Journal of China & Foreign Highway

To reveal the alkali excitation mechanism of high-dosage slag, this paper combines a three-factor, three-level orthogonal design with macro- and micro-performance tests and microstructure analysis. The effects of different activators, including Ca(OH)2, Na2SiO3, Na2SO4, and CaSO4, in single and dual combinations on the initial and final setting times, pore solution pH, and strength of concrete were explored. The results show that the impact on the strength of hardened paste of composite cementitious materials is ranked as: activator type > dosage > dual-mix ratio. The optimal dual-mix dosage is 4%, with the best combination being Ca(OH)2 and Na2SiO3 at a ratio of 5:1. …

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Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng May 2023

Study On Microstructure Of Asphalt Modified By Oil‐Coal Blend, Guo Pengfei, Zhou Xinfeng

Journal of China & Foreign Highway

To investigate the microstructure and modification mechanism of asphalt modified with oil-coal blend, SK-90# asphalt was mixed with 5%, 10%, 15%, 20%, and 25% (external blending method) oil-coal blend to produce modified asphalt. The performance and microstructural changes of the modified asphalt were analyzed using contact angle testing, infrared spectroscopy, cross-sectional SEM, and X-ray photoelectron spectroscopy. The results show that the oil-coal blend exhibits good compatibility with asphalt. During the modification process, esterification reactions occurred, resulting in a decrease in hydroxyl-containing aromatic compounds and an increase in carbonyl-containing aromatic compounds. Macroscopically, the oil-coal blend-modified asphalt demonstrated excellent high-temperature performance.

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Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan May 2023

Analysis Of Expressway Routine Maintenance Performance Management Based On Dea, Li Yuhuan, Shi Xiaoli, Gao Nan

Journal of China & Foreign Highway

To allocate maintenance resources efficiently and improve management levels, this paper examines the maintenance performance and improvement strategies of routine maintenance projects for 23 expressways in Shaanxi Province using 2018 operational maintenance data and data envelopment analysis. The results show that for some inefficient subsidiaries, traditional radial- and slack-based performance improvement methods are challenging and impractical in the short term. Therefore, a scenario-dependent model-based long-term incremental improvement strategy is proposed. By leveraging relative improvement values, this strategy enables phased improvements for inefficient subsidiaries. It provides a feasible approach for subsidiaries to set lower short-term performance improvement targets while achieving gradual …

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Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols May 2023

Du Undergraduate Showcase: Research, Scholarship, And Creative Works, Caitlyn Aldersea, Justin Bravo, Sam Allen, Anna Block, Connor Block, Emma Buechler, Maria De Los Angeles Bustillos, Arianna Carlson, William Christensen, Olivia Kachulis, Noah Craver, Kate Dillon, Muskan Fatima, Angel Fernandes, Emma Finch, Colleen Cassidy, Amy Fishman, Andrea Francis, Stacia Fritz, Simran Gill, Emma Gries, Rylie Hansen, Shannon Powers, Jacqueline Martinez, Zachary Harker, Ashley Hasty, Mykaela Tanino-Springsteen, Kathleen Hopps, Adelaide Kerenick, Colin Kleckner, Ci Koehring, Elijah Kruger, Braden Krumholz, Maddie Leake, Lyneé Alves, Seraphina Loukas, Yatzari Lozano Vazquez, Haley Maki, Emily Martinez, Sierra Mckinney, Audrey Mitchell, Kipling Newman, Audrey Ng, Megan Lucyshyn, Andrew Nguyen, Stevie Ostman, Casandra Pearson, Alexandra Penney, Julia Gielczynski, Tyler Ball, Anna Rini, Christina Rorres, Simon Ruland, Helayna Schafer, Emma Sellers, Sarah Schuller, Claire Shaver, Kevin Summers, Isabella Shaw, Madison Sinar, Claudia Pena, Apshara Siwakoti, Carter Sorensen, Madi Sousa, Anna Sparling, Alexandra Revier, Brandon Thierry, Dylan Tyree, Maggie Williams, Lauren Wols

DU Undergraduate Research Journal Archive

DU Undergraduate Showcase: Research, Scholarship, and Creative Works

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When Ai Moves Downstream, Frances S. Grodzinsky, Keith W. Miller, Marty J. Wolf May 2023

When Ai Moves Downstream, Frances S. Grodzinsky, Keith W. Miller, Marty J. Wolf

School of Computer Science & Engineering Faculty Publications

After computing professionals design, develop, and deploy software, what is their responsibility for subsequent uses of that software “downstream” by others? Furthermore, does it matter ethically if the software in question is considered to be artificial intelligent (AI)? The authors have previously developed a model to explore downstream accountability, called the Software Responsibility Attribution System (SRAS). In this paper, we explore three recent publications relevant to downstream accountability, and focus particularly on examples of AI software. Based on our understanding of the three papers, we suggest refinements of SRAS.

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Leveraging Neutrosophic Uncertainty Theory Toward Choosing Biodegradable Dynamic Plastic Product In Various Arenas, Mona Mohamed, Karam M. Sallam May 2023

Leveraging Neutrosophic Uncertainty Theory Toward Choosing Biodegradable Dynamic Plastic Product In Various Arenas, Mona Mohamed, Karam M. Sallam

Neutrosophic Systems with Applications

Numerous studies in recent years have documented the negative effects of plastic waste on the environment and human wellness. Due to their widespread usage in daily life, particularly in packaging, and their rising direct or indirect discharge into the environment, plastics are recognized as an emerging environmental hazard. Thus, this point is considered the first problem in this study. As a result, efforts to replace traditional plastics with bioplastics have intensified. However, studies regarding the effects of conventional and bioplastics (BioPs) are also important. Hence, biodegradable polymers for industrial and commercial usage are essential in the present day as an …

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Leveraging Neutrosophic Uncertainty Theory Toward Choosing Biodegradable Dynamic Plastic Product In Various Arenas, Mona Mohamed, Karam M. Sallam May 2023

Leveraging Neutrosophic Uncertainty Theory Toward Choosing Biodegradable Dynamic Plastic Product In Various Arenas, Mona Mohamed, Karam M. Sallam

Neutrosophic Systems with Applications

Numerous studies in recent years have documented the negative effects of plastic waste on the environment and human wellness. Due to their widespread usage in daily life, particularly in packaging, and their rising direct or indirect discharge into the environment, plastics are recognized as an emerging environmental hazard. Thus, this point is considered the first problem in this study. As a result, efforts to replace traditional plastics with bioplastics have intensified. However, studies regarding the effects of conventional and bioplastics (BioPs) are also important. Hence, biodegradable polymers for industrial and commercial usage are essential in the present day as an …

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Spectral Fits Of Brown Dwarfs: Discovering Trends Across The Spectral Type Sequence, Savanah Turner, Denise Stephens, Conner Scoresby May 2023

Spectral Fits Of Brown Dwarfs: Discovering Trends Across The Spectral Type Sequence, Savanah Turner, Denise Stephens, Conner Scoresby

Utah Space Grant Consortium

Brown dwarfs are substellar objects that form like stars but never achieve the core temperatures and pressures needed to ignite hydrogen fusion. These "failed stars" have been shown to exhibit complex atmospheres similar to those of planets, making them useful analogs for exoplanets. As a brown dwarf cools over time, different cloud species condense or fall below the surface of the atmosphere, causing changes in the resulting spectrum of the object. Comparison of theoretical atmospheric models to real brown dwarf spectra can provide insight into the physical and chemical processes occurring in the atmosphere of the object. We have fit …

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Comparing A 3-D Printed Hemispherical-Head And Rankine Body Probe Shapes For Very Low Speed Air Data Measurements, Stephen A. Whitmore, Zheng Qi C. Case May 2023

Comparing A 3-D Printed Hemispherical-Head And Rankine Body Probe Shapes For Very Low Speed Air Data Measurements, Stephen A. Whitmore, Zheng Qi C. Case

Utah Space Grant Consortium

This study investigates the feasibility of using Flush Air Data Sensing (FADS) System technology for air data measurements at the very low-airspeeds, where many Unmanned Aerial Vehicles (UAVs) operate. FADS is a non-intrusive alternative to pitot probes, where the vehicle nosecone, wing leading edge, or other aerodynamic surface is configured with multiple pressure-ports distributed along the windward surface. Although FADS technology has been used for a variety of high-speed aircraft, FADS has never been applied to very low-airspeed flight regimes. This study reports on wind tunnel tests of two 3-D printed shapes: 1) a cylindrical body with a hemispherical head, …

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Continuous-Time Trajectory Estimation For Differentially Flat Systems, Jacob C. Johnson, Joshua G. Mangelson, Randal W. Beard May 2023

Continuous-Time Trajectory Estimation For Differentially Flat Systems, Jacob C. Johnson, Joshua G. Mangelson, Randal W. Beard

Utah Space Grant Consortium

Continuous-time estimation using splines on Lie groups has been gaining traction in the literature in recent years due to their ability to incorporate high-frequency sensor data without introducing new optimization parameters. However, evaluating time derivatives and Jacobians of Lie group splines is computationally expensive, limiting their use mainly to offline applications. Motivated by the trajectory planning literature, we develop a new estimation technique that leverages the differential flatness property of many dynamic systems to define the spline in the system's flat output space, which is often Euclidean, and show an example of its use with the unicycle dynamic model. We …

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One-Dimensional Radial Turbomachinery Modeling, Chase Oliphant May 2023

One-Dimensional Radial Turbomachinery Modeling, Chase Oliphant

Utah Space Grant Consortium

Centrifugal flow impellers are commonly used in a wide variety of industrial machines. Predicting the performance of these impellers over the entire operating range is key to the system development during the early design stages. The two element in series (TEIS) and two-zone model can be used to accurately predict impeller performance based on flow physics and empirical correlations. Correlations were made with linear regression on a database of 50 pumps and 75 impellers. These correlations were later found to only apply to designs that are similar to those in the database. This paper proposes a new method to generate …

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A Preliminary Review And Discussion Of Metrics For Origami-Based Deployable Arrays, Katie Varela, Spencer P. Magleby May 2023

A Preliminary Review And Discussion Of Metrics For Origami-Based Deployable Arrays, Katie Varela, Spencer P. Magleby

Utah Space Grant Consortium

When designing deployable structures, there are many things to consider that help the deployment method integrate with the system. Preliminary metrics are proposed to help rate the deployment systems to determine the best methods for each application. The top four metrics that apply to most space applications are mass, usable area, volume, and energy. Additional considerations that are less quantifiable are included for the value they contribute to the system. Trade-offs may be necessary for different applications.

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Experimental Characterization Of Internal Wave Generation By Multiple Peak Topographies, Natasha Wilson, Julie Crockett May 2023

Experimental Characterization Of Internal Wave Generation By Multiple Peak Topographies, Natasha Wilson, Julie Crockett

Utah Space Grant Consortium

Internal waves are generated in the oceans and atmosphere and play an important role in their energy budgets. The semidiurnal oscillation of the tides over topography in the oceans combined with the density stratification can create internal waves that radiate away from their source. The effect multiple peaks on a single topography has on internal wave generation is explored. Three and four topography peaks create three and four crests respectively in the internal wave beams. Five and six peak topographies generate internal wave beams characterized by two bounding crests and several smaller crests in the middle of the beam. In …

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Development, Modeling And Performance Analysis Of An Electric Vtol Aircraft With Tiltable Rotors, Clayton Spencer, Samantha Burton, Tianyi He May 2023

Development, Modeling And Performance Analysis Of An Electric Vtol Aircraft With Tiltable Rotors, Clayton Spencer, Samantha Burton, Tianyi He

Utah Space Grant Consortium

In this paper, the development and modeling of an electric Vertical-Take-Off-and Landing (eVTOL) aircraft with tiltable rotors. The front two rotors have tilting capability for transition flight from vertical take-off to forward-direction level flight. This paper focuses on the design and analysis of an eVTOL aircraft platform. The study includes layout and system architecture, the selections and optimization of components, such as electric motors, batteries, and controllers, as well as the integration of these components into the overall aircraft system. In addition, the dynamical model is derived as a nonlinear differential equation. Afterwards, a linearization-based model and Linear Parameter-Varying (LPV) …

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Fabrication Of Metallic Far-Infrared Filters, Jared E. Payne, Joseph Eddy, Hunter R.J. Stevenson, Brad Ferguson, Ryan T. Beazer, Gregory N. Nielson, Stephen M. Shultz May 2023

Fabrication Of Metallic Far-Infrared Filters, Jared E. Payne, Joseph Eddy, Hunter R.J. Stevenson, Brad Ferguson, Ryan T. Beazer, Gregory N. Nielson, Stephen M. Shultz

Utah Space Grant Consortium

A far-infrared filter is fabricated by creating metallic squares on a dielectric substrate. This capacitive metallic filter is fabricated using direct write laser ablation consisting of a femtosecond laser in combination with a high numerical aperture objective. A representative capacitive filter is fabricated on soda-lime glass substrate with a period of 100 µm and separation width of 30 µm. A capacitive filter was also fabricated on a thin film polypropylene substrate with similar dimensions. The filter was tested and the frequency response is discussed.

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Facilitation Of Deployable Antennas Using A Panel Structure Optimization Framework, Nathan Coleman May 2023

Facilitation Of Deployable Antennas Using A Panel Structure Optimization Framework, Nathan Coleman

Utah Space Grant Consortium

Origami has become a popular method for beginning mechanical design due to its ability to stow compactly and deploy to a large area. One common origami pattern is the Flasher, which has a roughly circular shape and aspect ratio, centers around a polygon which can be grounded, and is easily extensible. Because of these advantages, the Flasher is a candidate for many deployable applications, including space-based optical telescopes, LiDaR telescopes, solar arrays, and reflectarray antennas. One of the primary difficulties when implementing the Flasher pattern is that it is not rigid-foldable and is subject to panel interference at high-degree vertices. …

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Optimizing Nitrogen Use For Continuous Recycling In Closed Life Support Systems, Noah J. Langenfeld, Bruce Bugbee May 2023

Optimizing Nitrogen Use For Continuous Recycling In Closed Life Support Systems, Noah J. Langenfeld, Bruce Bugbee

Utah Space Grant Consortium

Nitrogen (N) is needed by plants in the highest amount among root-zone-derived nutrients. Closed life-support systems for space missions will rely on in-situ food production for long-term sustainability, but high resupply and N fixation costs necessitate N recycling to support human nutrition for extended mission durations. We studied combinations of four N forms [ammonium, nitrate, urea, and N-fixing bacteria (protein)] for their use as an optimal N source for lettuce (Lactuca sativa) grown in peat moss in two container sizes (1.7 L and 8 L). Plants grown with ammonium nitrate consistently had the highest mass. When ammonium, urea, or microbial …

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Lasso (L1) Regularization For The Development Of Sparse Remote Sensing Models Of Water Quality, Anna C. Cardall, Riley C. Hales, Kaylee B. Tanner, Gustavious P. Williams, Kel N. Markert May 2023

Lasso (L1) Regularization For The Development Of Sparse Remote Sensing Models Of Water Quality, Anna C. Cardall, Riley C. Hales, Kaylee B. Tanner, Gustavious P. Williams, Kel N. Markert

Utah Space Grant Consortium

Remote sensing data (data contained in satellite imagery) are used extensively to monitor waterquality parameters such as clarity, temperature, and chlorophyll-a (chl-a). This is generally done bycollecting in situ data coincident with satellite data collections, then creating empirical water qualitymodels using approaches such as multi-linear regression or step-wise linear regression. Theseapproaches, which require modelers to select model parameters, may not be well-suited for opticallycomplex waters, where interference from suspended solids, dissolved organic matter, or otherconstituents may act as “confusers”. For these waters, it may be useful to include non-standard terms,which might not be considered using traditional methods. Recent machine learning …

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Measuring The Period Of Variable Stars In Ngc 188, Molly Christensen, Connor Smith, Christian Draper May 2023

Measuring The Period Of Variable Stars In Ngc 188, Molly Christensen, Connor Smith, Christian Draper

Utah Space Grant Consortium

Galactic cluster NGC 188 is 1.93 kpc away located in the constellation Cepheus. This cluster is one of the oldest clusters that contain W UMa stars W UMa variables are a type of eclipsing binary butare unique because they share an envelope of materia laround two stars. According to Simbad there are 741 interacting binaries in NGC 188. 70 of these are eclipsing binaries. We chose NGC 188 because it is an ideal place to study the evolution of W UMa stars because it is one of the oldest galactic clusters with this type of star. Despite the overabundance of …

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