Demonstration Of Coherent Optical Phase-Shift Keying With A Watt-Class 1550 Nm Tapered Diode Laser Amplifier For Free-Space Optical Communication Applications,
2026
Utah State University Space Dynamics Laboratory
Demonstration Of Coherent Optical Phase-Shift Keying With A Watt-Class 1550 Nm Tapered Diode Laser Amplifier For Free-Space Optical Communication Applications, Charlotte K. Duda, Aaron Cross, Chadwick Lindstrom, Julie Smith
Space Dynamics Laboratory Publications
High-power semiconductor optical amplifiers (SOAs) are a promising alternative to erbium-doped fiber amplifiers (EDFAs), which typically amplify the weak signals used in free-space optical (FSO) communications. In this work, we demonstrate that an Aura TM SOA operating with 1 W output power can be used to transmit phase-shift key (PSK) protocols required of next-generation FSO communication networks. Firstly, we demonstrate successful transmission of binary phase-shift keying (BPSK) for bit rates up to 50 Gbps. Secondly, we demonstrate successful transmission of quadrature phase-shift keying (QPSK) for bit rates up to 100 Gbps. For both PSK protocols, we demonstrate comparable constellation error-vector …
Investigation Of Material Properties Of Thermoplastic And Thermoset Polymer Materials At Cryogenic Temperatures Using Molecular Dynamics,
2026
Michigan Technological University
Investigation Of Material Properties Of Thermoplastic And Thermoset Polymer Materials At Cryogenic Temperatures Using Molecular Dynamics, Swapnil S. Bamane, Sagar Patil, Khatereh Kashmari, Benjamin D. Jensen, Brett A. Bednarcyk, Evan J. Pineda, Jeffery Hinkley, Ozgur Keles, Jin Ho Kang, Gregory Odegard
Michigan Tech Publications
Cryogenic fluids, such as liquid hydrogen and liquid oxygen, are critical for space operations as rocket fuel and life support. The fluids need to be contained in tanks that can withstand the effects of cyclic thermal and pressure loading throughout their lifecycle. Polymer matrix composites (PMCs) are prime candidates for these tanks because of their low mass, which is important for fuel savings. Although advanced PMC systems have been developed for a wide range of engineering applications, insight is still needed to identify optimal polymer matrix materials for cryogenic structural applications. The objective of this study is to use molecular …
Applying Direct Numerical Simulations To Investigate Wave Forcing Against A Vertical Wall,
2026
Missouri University of Science and Technology
Applying Direct Numerical Simulations To Investigate Wave Forcing Against A Vertical Wall, Hunter Boswell, Frank D. Han, Gaurav Savant, Guirong Yan, Wouter Mostert
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Current engineering standards lack the ability to predict the peak impact forces of breaking waves impinging directly upon coastal structures. In this study solitary waves impacting vertical and tapered walls are investigated. To capture the detailed physics of the wave profile that impacts the wall, two-dimensional direct numerical simulations are applied to model the wave traveling over a simplified bathymetry consisting of an initially uniform depth, followed by a uniform beach ramp and then terminating in a uniform depth inshore region and vertical wall. Such an approach can simulate wave runup on land and then the impact with the vertical …
A Scalable Iteration Of The Horizon Simulation Framework Using Multithreading Techniques,
2026
California Polytechnic State University, San Luis Obispo
A Scalable Iteration Of The Horizon Simulation Framework Using Multithreading Techniques, Jason E. Beals
Master's Theses
The Horizon Simulation Framework (HSF) occupies a unique space in the modern aerospace modeling landscape, enabling flexible, modular modeling of mission-level agent behavior through an object-oriented, hierarchical design. HSF's hallmark breadth-first search scheduling algorithm explores a "multiverse" of possible mission execution pathways, enabling exhaustive evaluation of schedule combinations against user-defined heuristics.
As aerospace systems become increasingly complex, HSF faces critical challenges in establishing verifiable, deterministic behavior. The framework's core scheduling algorithm had not undergone systematic validation, leaving questions about temporal consistency, state management correctness, and reproducibility across different program executions. Furthermore, the exponential growth of schedule combinations creates computational bottlenecks …
Informing Consumer Product Sound Quality Analysis Using Generative Adversarial Networks,
2026
Michigan Technological University
Informing Consumer Product Sound Quality Analysis Using Generative Adversarial Networks, Daniel Jeffery Lesko, Vinh Nguyen
Michigan Tech Publications
Sound quality attributes have been proven important predictors of customer satisfaction with consumer goods and appliances. The results of several studies indicate that level-based, tonal, and temporal aspects of sound influence the perceived quality of consumer products. The current state-of-the-art of inferring consumer satisfaction with sound attributes is based on the jury test methodology. However, product engineers often find the models generated from these studies incomplete, resulting in products that fail to meet consumer expectations. Therefore, this study aims to utilize generative data-driven approaches to create a range of acceptable sound quality attributes given consumer satisfaction requirements. A baseline sound …
Evaluating Regularized Logistic Regression And K-Nn On Mnist Under Increasing Random Missingness,
2026
University of Central Florida
Evaluating Regularized Logistic Regression And K-Nn On Mnist Under Increasing Random Missingness, Daniel Markwei
Data Science and Data Mining
This paper investigates the effect of random missingness on the performance of regularized multinomial logistic regression and the k-nearest neighbors (k-NN) classifier for handwritten digit recognition on the MNIST dataset. In particular, we study L1-regularized (LASSO) logistic regression and L2-regularized (Ridge) logistic regression alongside k-NN. Varying percentages of random missingness were introduced into the original dataset, and each model was evaluated in terms of its classification performance. The results show that random missingness degrades the performance of all three classifiers. Overall, k-NN consistently achieves higher accuracy than both L1- and L2-regularized logistic regression across all missingness levels; however, its performance …
A Pathfinder Lunar Construction Mission Concept Using Regolith Filled Bags,
2026
MDA Space Ltd.
A Pathfinder Lunar Construction Mission Concept Using Regolith Filled Bags, Cameron S. Dickinson, Fu Nan Shi, Ketan Vasudeva, Rudranarayan M. Mukherjee, Joshua Blanchard, Steve Dubrule, Paul Van Susante, Et Al.
Michigan Tech Publications
Two challenges that have a permanent presence on the Moon are solar and cosmic radiation, as well as the large surface temperature variation between lunar day and night. To address these problems, we propose a lunar pathfinder mission concept that uses robotic systems to investigate whether regolith-filled bags can be used as a versatile construction medium for lunar surface structures and sensors to obtain data on the lunar regolith. The primary objectives of this mission are as follows: evaluation of the surface and subsurface regolith as fill material, lunar excavation using a robotic manipulator equipped with a bucket scoop, bag …
Rapid-Response Reconnaissance Architecture Design For Planetary Defense With Nested Trajectory Optimization,
2026
University of Colorado, Boulder
Rapid-Response Reconnaissance Architecture Design For Planetary Defense With Nested Trajectory Optimization, Adam P. Wilmer, Justin A. Atchison, Marcus J. Holzinger, Robert A. Bettinger
Faculty Publications
Reconnaissance is a vital component in a comprehensive planetary defense mitigation strategy—aimed at preventing or reducing the impact threat posed by celestial objects on close-approach trajectories to Earth. It provides decision-makers with critical information on the physical and orbital properties of a near-Earth object (NEO), enabling better assessment of size, composition, and trajectory. This study investigates how to optimally pre-position a fleet of reconnaissance spacecraft prior to the discovery of a specific hazardous NEO. It evaluates response timelines and mission success rates for combinations of spacecraft launched from Earth and those maneuvering from pre-deployed locations within the Sun-Earth system. A …
Mae Enewsbrief Oct-Dec 2025,
2026
Michigan Technological University
Mae Enewsbrief Oct-Dec 2025, Department Of Mechanical And Aerospace Engineering, Michigan Technological University
Department of Mechanical and Aerospace Engineering eNewsBrief
No abstract provided.
Discovery Of Dynamical Structures Mapping Chaotic Transport Pathways In The Earth–Moon Cr3bp,
2026
Air Force Institute of Technology
Discovery Of Dynamical Structures Mapping Chaotic Transport Pathways In The Earth–Moon Cr3bp, Tyler J. Kapolka, Christina E. Paljug, Robert A. Bettinger, Rachel Oliver, Bruce A. Cox, Jeremiah A. Specht
Faculty Publications
Chaos; Deterministic chaos; Earth–Moon system; Poincaré map; Quasi-chaotic; Surface of section /// For the Circular Restricted 3-Body Problem (CR3BP), the topologies present within a Poincaré map enable the extraction of useful information regarding periodic, quasi-periodic, and chaotic trajectory behavior. Aside from the prominent topologies that follow distinct concentric patterns around fixed points, indicative of the periodic and quasi-periodic motion that is often the central focus of CR3BP research, there are also many “dusty” regions on the Poincaré map that appear random without an apparent structure and are indicative of chaotic motion. This paper, for the first time in literature, identifies …
Flow Over A Cylinder With A Small Triangular Bump,
2026
Minnesota State University, Mankato
Flow Over A Cylinder With A Small Triangular Bump, Jack Elliott, Alex Nielson, Barton L. Smith
Integrated Engineering Department Publications
The surface pressure distribution over a circular cylinder with a small, full-span, triangular bump is examined. The geometry of the bump is an isosceles triangle, the height of which is varied from 1.33 % to 5.33 % of the diameter of the cylinder and positioned between 60° and 120°. The Reynolds number (Re=V∞ D/ν, where V∞ is the velocity of the freestream, D is the diameter of the cylinder and ν is the kinematic viscosity) is varied between 1.1×105 and 1.8×105. The lift and drag are estimated through the surface integral of pressure over the cylinder. The results show that …
Flexible Fault-Tolerant Multi-Die Fpga-Based Architectures For Varying Space Environments,
2026
The American University in Cairo AUC
Flexible Fault-Tolerant Multi-Die Fpga-Based Architectures For Varying Space Environments, Yosof Ali Seif El Din Ali Maklad
Theses and Dissertations
It is well-known fact that spacecraft’s electronic components operate in an extreme harsh and varying space environments, beside changing orbit or passing through Van Allan Belts during orbital course results of radiation levels change. This thesis focuses on SRAM-based FPGA systems on-board of such spacecrafts, that are commonly utilized in space applications’ critical applications due to their capabilities and flexibility to reconfigure, since these systems are vulnerable to frequent negative impacts of ionizing radiation, thus inducing soft and hard errors leading to disastrous failures that could jeopardize the entire spacecraft. The soft errors’ effects are frequent yet can be mitigated, …
Polar Reconnaissance & Imagining Survey (Polaris),
2026
Embry-Riddle Aeronautical University
Polar Reconnaissance & Imagining Survey (Polaris), Max Brooks, Zion Carpenter, Isabel La Coss
Student Research Symposium (SRS)
In preparation for the permanent human presence on the lunar south pole as part of the ARTEMIS Accords, planned human excursions will conduct science on regions of interest to locate resources for sustained habitation. The objective of the Polar Reconnaissance & Imaging Survey simulation is to take a predetermined region sized image of a planned astronaut excursion site to identify terrain features and threats. This shall be a satellite mission control (MCC) simulation with four Earth-based satellite console operators, and one moon-based EVA encompassing.
Uav-Deployable Open-Source Sensor Nodes For Spatial And Temporal In Situ Water Quality Monitoring And Mapping,
2026
University of South Carolina
Uav-Deployable Open-Source Sensor Nodes For Spatial And Temporal In Situ Water Quality Monitoring And Mapping, Matthew Burnett, Mohamed Abdelwahab, Joud N. Satme, Austin Downey, Gabriel Barahona Smith, Antonio Fonce, Jasim Imran
Faculty Publications
Cost efficient, spatially resolved water quality monitoring is essential for managing pollution and protecting aquatic ecosystems. This study presents a low-cost (approximately USD 200), open-source, unmanned aerial vehicle (UAV)-deployable in situ sensor node for real-time assessment of surface-water conditions. The system integrates sensors for pH, turbidity, temperature, and total dissolved solids (TDSs), with onboard data logging and real-time clock (RTC) synchronization. Bench validation of the sensor package yielded mean absolute percentage errors of 1.34% for pH, 5.23% for TDS, and 0.81% for temperature, and the device operated continuously for 42 h. Field deployment demonstrated its ability to resolve spatial gradients, …
Bulk Absorber Acoustic Characterization Via The Two-Cavity Impedance Tube Methoda),
2026
Michigan Technological University
Bulk Absorber Acoustic Characterization Via The Two-Cavity Impedance Tube Methoda), Anthony Ciletti, Janith Godakawela, Martha Brown, Bhisham Sharma
Michigan Tech Publications
The primary goal of this study is to investigate and refine the two-cavity impedance tube method for acoustic characterization of bulk porous materials, specifically addressing previously unexplained inaccuracies in the prediction of surface impedance and absorption coefficients. Unlike the conventional two-thickness approach, the two-cavity method requires only one sample thickness and involves conducting measurements at various air cavity depths behind the sample. The initial analyses revealed previously unidentified numerical instabilities, resulting in anomalous predictions of sound absorption at specific frequencies. Through systematic investigation and use of calculated data, the numerical origins of these anomalies are uncovered and a practical solution, …
Generative Artificial Intelligence In Aircraft Design Optimization,
2026
Missouri University of Science and Technology
Generative Artificial Intelligence In Aircraft Design Optimization, Xiaosong Du
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Aircraft design optimization is essential for improving aircraft performance (such as reduced fuel consumption and lowered noise), which leads to more efficient, sustainable, and affordable aircraft. Conventional aircraft design adopts physics-based simulation models, but iteratively evaluating simulation models is computationally intensive, or even practically impossible. Meanwhile, artificial intelligence (AI) emerges as a revolutionary game changer in the modern engineering industry, including aircraft design optimization. Generative AI (genAI), one of the groundbreaking AI methods, has been advancing aircraft design optimization from various aspects, including intelligent parameterization, predictive modeling, training facilitation, and constraints handling. However, there is a lack of a review …
A Closer Look At Shielding Gas In Laser Powder Bed Fusion: A Review,
2026
Utah State University
A Closer Look At Shielding Gas In Laser Powder Bed Fusion: A Review, Tasrif Ul Anwar, Nadia Kouraytem
Mechanical and Aerospace Engineering Student Publications and Presentations
The ongoing advancement of additive manufacturing (AM) techniques, particularly in laser powder bed fusion (LPBF), is effectively bridging the knowledge gap between AM and conventional manufacturing methods. At present, most of the research is focused on optimizing key process parameters such as laser power, laser speed, hatch spacing, layer thickness, scan pattern, powder size distribution, and so on. These studies help improve the part density and refine the microstructure of LPBF components, thereby enhancing the mechanical properties. Despite these advancements, an area in LPBF that is receiving comparatively less attention is the shielding gas: its flow during the printing process, …
Statistical Analysis Of Log Transformation Effectiveness In Air Traffic Movement Forecasting During Covid-19 In South Africa,
2026
University of the Free State
Statistical Analysis Of Log Transformation Effectiveness In Air Traffic Movement Forecasting During Covid-19 In South Africa, John Lehlaka Masekoameng
Journal of Aviation Technology and Engineering
This study evaluates the effectiveness of log transformation in enhancing multiple regression models used to forecast air traffic movements (ATMs) in South Africa during the COVID-19 pandemic. Using 60 monthly observations from October 2016 to September 2021, the analysis incorporates variables such as revenue, lockdown levels, COVID-19 metrics, exchange rates, gross domestic product, and population. Two models are compared: one using raw ATMs and another with log-transformed ATMs as the dependent variable.
While the untransformed model shows stronger explanatory power (R² = 0.904, adjusted R² = 0.891) compared to the log-transformed model (R² = 0.772, adjusted R² = 0.741), the …
Spline-Based Factor-Graph Optimization With High-Grade Inertial Sensors,
2026
Autonomy and Navigation Technology Center, Air Force Institute of Technology
Spline-Based Factor-Graph Optimization With High-Grade Inertial Sensors, Kyle Leland, Clark N. Taylor, David Woodburn, Randal Beard
Faculty Publications
Inertial measurement units (IMUs) are central to global navigation satellite system-based and alternative navigation solutions. This paper combines three lines of research to explore a novel methodology for using inertial sensors: factor graphs, spline-based trajectory estimation, and high-grade inertial sensing. Spline-based factor-graph trajectory estimation is increasingly used in the literature, especially for asynchronous or high-rate sensors. However, prior models neglect the impact of the Earth’s rotation, which is significant for high-grade IMUs. We extend spline-based factor graphs to incorporate accelerometer and gyroscope models that account for the Earth’s rotation. We apply this approach to simulated data from high-grade inertial sensors …
Improved Performance Of Wave Energy Converters And Arrays For Wave-To-Onshore Power Grid Integration,
2026
University of Michigan, Ann Arbor
Improved Performance Of Wave Energy Converters And Arrays For Wave-To-Onshore Power Grid Integration, Madelyn Veurink, David Wilson, Rush Robinett, Wayne Weaver
Michigan Tech Publications
This paper focuses on power grid integration of wave energy converter (WEC) arrays that minimize added energy storage for maximizing power capture as well as smoothing the oscillatory power inputs into the grid. In particular, a linear right circular cylinder WEC array that implements complex conjugate control is compared and contrasted to a nonlinear WEC array that implements an hourglass buoy shape while both are integrated into the grid utilizing phase control (i.e., relative spacing of the WEC array) on the input powers to the grid. The Hamiltonians of the two WEC systems are derived, enabling a direct comparison of …
