A Hardware-In-The-Loop Star Tracker Test Bed,
2024
California Polytechnic State University, San Luis Obispo
A Hardware-In-The-Loop Star Tracker Test Bed, Ashley Haraguchi
Master's Theses
As the use of small satellites for advanced space missions continues to grow, the importance of low mass and cost three-axis attitude stabilization systems increases as well, with these systems requiring high accuracy attitude knowledge. Star trackers provide the most accurate attitude knowledge of any type of attitude sensor, but the high cost, size, and weight of commercial star trackers can be prohibitive to small satellite missions. Many simple star trackers have been developed using commercial off-the-shelf camera sensors and processing hardware, but the challenge remains in testing and characterizing these devices. A common solution is night sky tests, in …
Preliminary Analysis Of A 12u Astronomy Cubesat,
2024
California Polytechnic State University, San Luis Obispo
Preliminary Analysis Of A 12u Astronomy Cubesat, Charles Van Steenwyk
Master's Theses
The explosion of exoplanet astronomy has led to thousands of new discoveries and opportunities to be explored. The ability to capture images and perform meaningful science has resulted in an abundance of follow-on missions, surveys, and fostered a community of amateur astronomers in the last ten years. This success mirrors the development of CubeSats, which have proved an immensely popular way for students of all levels to access space and collect data. Multiple CubeSats have been developed to observe and characterize single exoplanet tran- sits, showing that this class of mission is possible. However, there is currently no mission designed …
The Effect Of Atomic Oxygen On Additively Manufactured Materials,
2024
California Polytechnic State University, San Luis Obispo
The Effect Of Atomic Oxygen On Additively Manufactured Materials, Ryan Grogan
Master's Theses
Additive manufacturing (AM) is a rapidly developing manufacturing method utilized in fields such as the aerospace industry. In-space AM is a technology of interest for the future of spaceflight, including on-orbit manufacturing. However, AM materials are subject to defects that may impact their performance in space-based applications. How these defects change the material’s reaction to the space environment, specifically atomic oxygen (AO), has only recently been explored. AO is a highly corrosive, dominant constituent in low Earth orbit that causes continuous erosion of spacecraft surfaces. The effect of AO on various AM materials is investigated in this thesis. Stainless steel, …
Pkt-Sin: A Secure Communication Protocol For Space Information Networks With Periodic K-Time Anonymous Authentication,
2024
Fuzhou University
Pkt-Sin: A Secure Communication Protocol For Space Information Networks With Periodic K-Time Anonymous Authentication, Yang Yang, Wenyi Xue, Jianfei Sun, Guomin Yang, Yingjiu Li, Hwee Hwa Pang, Robert H. Deng
Research Collection School Of Computing and Information Systems
Space Information Network (SIN) enables universal Internet connectivity for any object, even in remote and extreme environments where deploying a cellular network is difficult. Access authentication is crucial for ensuring user access control in SIN and preventing unauthorized entities from gaining access to network services. However, due to the complex communication environment in SIN, including exposed links and higher signal delay, designing a secure and efficient authentication scheme presents a significant challenge. In this paper, we propose a secure communication protocol for SIN with periodic k-time anonymous authentication (named PkT-SIN) that allows satellite users to anonymously authenticate to ground stations …
Disposal And Earth-Moon Escape From Cislunar Orbits Using Non-Linear Programming Techniques,
2024
Air Force Institute of Technology
Disposal And Earth-Moon Escape From Cislunar Orbits Using Non-Linear Programming Techniques, Sam T. Loeffler
Theses and Dissertations
This thesis involves theoretical and numerical analysis of trajectories off of cislunar orbits to determine the reachability and escape of various impulsive Δ→v. The research will propagate trajectories using three body dynamics from various orbit families around the Earth-Moon Lagrange points and find low energy transfers that escape the Earth-Moon system. In order to achieve this, various different nonlinear programming solvers in MATLAB will be used to explore low energy impulsive escape transfers from common cislunar orbit families given long periods of computation time. After many points on cislunar orbits are analyzed, the data will be analyzed to …
Heat Sink With Fins And Phase Change Material For Cooling Of High-Power Electronic Devices,
2024
United Arab Emirates University
Heat Sink With Fins And Phase Change Material For Cooling Of High-Power Electronic Devices, Farooq Fakher Mahmoud
Theses
Electronics are integral to modern life, present in everything from household appliances to advanced computers. The performance and reliability of these devices are closely tied to their operating temperatures. High-power operations can lead to significant heating, necessitating effective thermal management to enhance functionality and prevent failure. This requirement drives the demand for efficient heat sinks, which dissipate the heat generated by these devices. Phase change material (PCM)-based heat sinks have become a popular passive cooling solution, increasingly replacing traditional heat sinks.
This research investigates finned PCM-based heat sinks using numerical simulations validated by existing literature and experimental data. Gallium is …
Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge,
2024
New Jersey Institute of Technology
Interaction Of Particles With Plasma And Shock Produced By Pulsed Spark Discharge, Shomik Mukhopadhyay
Dissertations
Interactions of powders with high-temperature plasma and shockwaves occur in diverse scenarios, such as nuclear blasts, accidental industrial dust explosions, solid propellant combustion in explosive charges and when removing contaminants from surfaces. Electrostatic Discharge (ESD), known for generating shock and plasma, is a promising lab-scale technique for simulating these interactions. Studies with ESD involved placing powders near a spark-producing gap between electrodes and observing mechanical and chemical processes like particle motion and ignition. A limited range of spark conditions and material properties have been tested, which facilitated the development and validation of preliminary computational models describing this system. Significant gaps …
Reproducible Fluid Structure Interaction For Complex Flows In Engineered Systems,
2024
New Jersey Institute of Technology
Reproducible Fluid Structure Interaction For Complex Flows In Engineered Systems, Allen Prasad Varghese
Dissertations
This dissertation focuses on the application of numerical models to study Fluid Structure Interaction (FSI) in the industrial context. The emphasis is on a series of case studies belonging to practical applications in design and manufacturing and that are solved by a synergistic use of theoretical and computational models. The first study looks into the hydrodynamic actions experienced by vibrating slender structures immersed in viscous fluids near the free surface. This study case is relevant to applications such as, for example, marine propulsion, micro-electro-mechanical systems, and atomic force microscopy. The hydrodynamic problem is governed by three parameters, namely the frequency, …
Consequences Of Spatial Heterogeneity For Turbulent Wake Development,
2024
Portland State University
Consequences Of Spatial Heterogeneity For Turbulent Wake Development, Ryan Scott
Dissertations and Theses
Spatial heterogeneity is an fundamental property of natural systems. In fluid dynamics subtle variations in fluid motion give rise to chaotic turbulent flows. When a fluid passes an object it retains an imprint of the object as a momentum deficit known as a wake. The resulting spatial structure of the wake is intrinsically linked to the object responsible for its creation. The coupling between geometric complexity in wake producing entities and turbulent wake evolution is considered in terms of spatial heterogeneity from individual wakes through turbulent canopy flows. First a novel Lacunarity-based method is developed for quantifying spatial heterogeneity in …
Raditation Test Report: Characterization Of Fairchild Imaging Cis2521 Cmos Focal Plane Array,
2024
Utah State University
Raditation Test Report: Characterization Of Fairchild Imaging Cis2521 Cmos Focal Plane Array, Space Dynamics Laboratory
Space Dynamics Laboratory Publications
This report documents the results of radiation testing of Fairchild CIS2521 CMOS imaging sensor. Proton radiation measurements (both transient and total ionizing dose) were performed at the Crocker Nuclear Laboratory (CNL) of the University of California, Davis (UC Davis). Latchup characterization using Heavy Ion radiation was performed at the Texas A&M University Cyclotron Institute, Radiation Effects Facility.
Infrared Phase-Change Chiral Metasurfaces With Tunable Circular Dichroism,
2024
Missouri University of Science and Technology
Infrared Phase-Change Chiral Metasurfaces With Tunable Circular Dichroism, Haotian Tang, Liliana Stan, David A. Czaplewski, Xiaodong Yang, Jie Gao
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Integrating Phase-Change Materials in Meta surfaces Has Emerged as a Powerful Strategy to Realize Optical Devices with Tunable Electromagnetic Responses. Here, Phase-Change Chiral Meta surfaces based on GST-225 Material with the Designed Trapezoid-Shaped Resonators Are Demonstrated to Achieve Tunable Circular Dichroism (CD) Responses in the Infrared Regime. the Asymmetric Trapezoid-Shaped Resonators Are Designed to Support Two Chiral Plasmonic Resonances with OppositeCDresponses for Realizing SwitchableCDbetween Negative and Positive Values using the GST Phase Change from Amorphous to Crystalline. the Electromagnetic Field Distributions of the Chiral Plasmonic Resonant Modes Are Analyzed to Understand the Chiroptical Responses of the Meta surface. Furthermore, the …
Experimental Investigation On Downstream Characteristics Of S809 Airfoil With And Without Passive Flow Control Device,
2024
SASTRA Deemed to be University
Experimental Investigation On Downstream Characteristics Of S809 Airfoil With And Without Passive Flow Control Device, Mano S
Theses and Dissertations
The wake behaviour of extended flat plate (EFP) and serration in the trailing edge of S809 airfoil is presented in this experimental study using wind tunnel testing for several freestream turbulence intensities (TI). The clustering wind turbines in wind parks has recently been an important problem, as it involves determining the number of wind turbines to be installed to increase the power output.
The downstream wake characteristics are one of the most significantparameter that influence the performance of subsequent wind turbines.These wind turbine blades are made up of airfoil cross sections and need to be studied in detail. A series …
New Frontier In Race For Deep Space Exploration: Lunar Water Resources,
2024
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China
New Frontier In Race For Deep Space Exploration: Lunar Water Resources, Yong Wei, Honglei Lin, Fei He, Hui Zhang
Bulletin of Chinese Academy of Sciences (Chinese Version)
Deep space exploration has become the commanding heights of science and technology competition. Since the beginning of the 21st century, China has successfully completed the lunar exploration missions of “orbiting, landing, and returning” in just twenty years, and upgraded to a new roadmap of “survey, construction, and utilization”. Meanwhile, lunar exploration worldwide has shown a trend towards normalization and commercialization. The research on lunar water resources has sparked widespread interest and intense competition among countries and space agencies, marking a new focus in human’s deep space exploration. The exploration of lunar water can help reveal crucial processes in the formation …
Winning Battle For Key And Core Technologies In Emerging Fields—Inspiration Based On 863 Program Related Projects,
2024
Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
Winning Battle For Key And Core Technologies In Emerging Fields—Inspiration Based On 863 Program Related Projects, Guangzu Bai, Li Li, Hongfei Meng, Qiang Wang, Xiaoyang Cao, Anrong Liu, Bo Cheng, Mimi Zhan, Jing Li, Leiei Cui, Xiangwan Du
Bulletin of Chinese Academy of Sciences (Chinese Version)
Emerging technology fields have become the main battleground for strategic competition among major powers today, with key and core technologies serving as crucial approach in shaping a nation’s international competitive advantage. This study, from the perspective of national strategy, profoundly understands the significant importance of winning the key and core technology battle in emerging fields. Based on this understanding, it starts with a comparison between the implementation background of the 863 Program and the current reality. It systematically summarizes valuable experiences from projects aimed at advancing key and core technologies in emerging fields, and puts forward reflections and suggestions for …
Redeveloping System Noise Temperature Test Capabilities For Dss-17 Using The Moon As A Noise Source,
2024
Morehead State University
Redeveloping System Noise Temperature Test Capabilities For Dss-17 Using The Moon As A Noise Source, Emily R. Walter
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Science and Engineering at Morehead State University in partial fulfillment of the requirements for the Degree Master of Science by Emily R. Walter on May 16, 2024.
Development, Numerical Simulation And Turbulence Modeling Of A Sustainable Transonic Truss-Braced Wing Aircraft Using Liquid Hydrogen Fuel And Active Flow Control,
2024
Washington University in St. Louis
Development, Numerical Simulation And Turbulence Modeling Of A Sustainable Transonic Truss-Braced Wing Aircraft Using Liquid Hydrogen Fuel And Active Flow Control, Bryce Zachary Thomas
McKelvey School of Engineering Graduate Student Theses & Dissertations
There is pressing need for emissions reduction and an increase in efficiency for the next generation of commercial aircraft in order to reduce the environmental impact of the aviation sector and combat global climate change. The implementation of alternative fuels as well as new engine and wing designs are actively being explored as methods to reduce emissions. This thesis analyzes the implementation of hydrogen fuel, a transonic truss braced wing and active flow controls as means to improve the performance of a medium range commercial airliner. The widespread adoption of cryogenic liquid hydrogen (LH2) fuel as a green alternative to …
Regular Algorythms For Synthesis Of Optimal Control Systems For Dynamic Objects,
2024
Tashkent State Technical University, Tashkent city, Republic of Uzbekistan, DSc, professor, academician, [email protected], https://orcid.org/0000-0003-3047-526;
Regular Algorythms For Synthesis Of Optimal Control Systems For Dynamic Objects, Igamberdiyev Husan, Uktam Farkhodovich Mamirov, Xankeldiyeva Zebiniso
Technical science and innovation
The article presents algorithms for the synthesis of an optimal control system for dynamic objects. As a model, we consider a differential equation of a continuous one-dimensional system in the form of a state space, which has the properties of controllability and observability. The paper shows the need to use an observation device in order to assess how the properties of the controlled system change with the slightest change in the parameters of the control object, to assess the sensitivity of the system to these changes. When finding a solution to the equation formulated to find the parameters of the …
Heat Sink Integrating Phase Change Materials For Cooling High Power Electronic Devices,
2024
United Arab Emirates University
Heat Sink Integrating Phase Change Materials For Cooling High Power Electronic Devices, Mohammad Sameer Qasem
Thesis/ Dissertation Defenses
This research explores the numerical analysis of phase change materials (PCMs) heat sinks, focusing on high heat flux dissipation applications, e.g. electronics cooling. Both 2D and 3D numerical models using gallium and paraffin RT31 as PCMs are considered within a heat sink design framework featuring a rectangular cavity and dual opposing vertical copper walls serving as fins to dissipate heat from the hot sink base that receives heat from the heat source. The inclusion of a Triply Periodic Minimal Surface (TPMS) ‘Primitive’ structure as an in-fill thermal conductivity enhancer (TCE) in the case of the gallium heat sink, and a …
The Conceptual Design, Analysis And Optimization Of A Hydrogen Combustion And A Hydrogen Fuel-Cell Powered Aircraft,
2024
Washington University in St. Louis
The Conceptual Design, Analysis And Optimization Of A Hydrogen Combustion And A Hydrogen Fuel-Cell Powered Aircraft, Michael Kiely
McKelvey School of Engineering Graduate Student Theses & Dissertations
In the effort to combat climate change worldwide, the aviation industry faces particularly complex design challenges in designing new, emission free vehicles. One potential solution to this problem is the use of hydrogen fuel as a means of propulsion. Hydrogen fuel has many benefits over traditional jet fuel such as a higher gravimetric energy density; however, it requires the aircraft to carry large, pressurized, cryogenic fuel tanks. This thesis examines the design challenges, potential solutions, and the analysis methods for the design of a short to medium range hydrogen powered commercial airliner. To accomplish this goal, a comprehensive conceptual design …
Emulsion Stability, Rheological Properties, And Combustion Characteristics Of Waterjojoba Biofuel Emulsion,
2024
United Arab Emirates University
Emulsion Stability, Rheological Properties, And Combustion Characteristics Of Waterjojoba Biofuel Emulsion, Ihab Mohamed Ayad
Thesis/ Dissertation Defenses
This thesis comprehensively investigates the stability, rheological properties, and engine performance implications of water in jojoba biodiesel (WJBD) emulsion. The research delves into multiple aspects, including the influence of diverse surfactants and water concentrations on emulsion stability. It also yields valuable insights into the development of stable water in jojoba biodiesel emulsions, specifically tailored for diesel engines. These insights contribute significantly to the body of knowledge of positioning emulsion fuels as viable alternative to traditional diesel fuels. The anticipated benefits include notable reductions in emissions. Importantly, this study underscores the critical importance of considering emulsion stability, both during storage and …
