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Missouri University of Science and Technology

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Articles 421 - 450 of 1155

Full-Text Articles in Aerospace Engineering

Characterization Of A Green Electric Solid Propellant For Electric Propulsion, Matthew Scott Glascock Jan 2019

Characterization Of A Green Electric Solid Propellant For Electric Propulsion, Matthew Scott Glascock

Doctoral Dissertations

"Electric solid propellants are advanced solid chemical rocket propellants that can be controlled (ignited, throttled and extinguished) through the application and removal of an electric current. These propellants are also being considered for use in ablative pulsed plasma thruster and multimode systems. In this work, the behavior and performance of a novel green electric solid propellant operating in an electrothermal ablation-fed pulsed plasma thruster was investigated. Using an inverted pendulum micro-Newton thrust stand, the impulse bit and specific impulse of the device using the electric solid propellant were measured for short-duration and long-duration runs to end-of-life, at energy levels of …

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Prediction Of Thermal Conductance At Liquid-Gas Interfaces Using Molecular Dynamics Simulations, James Gonzalez, Josue Ortega, Zhi Liang Nov 2018

Prediction Of Thermal Conductance At Liquid-Gas Interfaces Using Molecular Dynamics Simulations, James Gonzalez, Josue Ortega, Zhi Liang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Using Molecular Dynamics (MD) Simulations and Theoretical Calculations, We Study Heat Transfer Across Liquid-Gas Interfaces within a Planar Heat Pipe. to Determine the Thermal Conductance (Kapitza Conductance), GK, at the Interface, Two Heat Transfer Mechanisms, Namely, Conduction and Evaporation/condensation Are Considered. in the Case of Interfacial Heat Conduction, Gas Molecules, Particularly Non-Condensable Gas Molecules, Exchange Heat with Liquid Surfaces through Gas-Liquid Collisions, and the Theoretical Expression for GK is Derived from the Kinetic Theory of Gases. for Interfacial Heat Transfer by Evaporation or Condensation, the Theoretical Expression for GK is Derived from the Schrage Relationships. to Assess the Accuracies of …

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Evaluation Of The 20 L Dust Explosibility Testing Chamber And Comparison To A Modified 38 L Vessel For Underground Coal, Robert Quentin Eades, Kyle A. Perry, Catherine E. Johnson, Jacob Miller Nov 2018

Evaluation Of The 20 L Dust Explosibility Testing Chamber And Comparison To A Modified 38 L Vessel For Underground Coal, Robert Quentin Eades, Kyle A. Perry, Catherine E. Johnson, Jacob Miller

Mining Engineering Faculty Research & Creative Works

The phenomenon of combustible dust explosions is present within many industries. Tests for explosibility of dust clouds per ASTM E1226 use a 20 L explosive chamber that places the combustible dust directly below the dispersion nozzle which generates a thorough mixture for testing purposes. However, in the underground coal mining industry, there are a number of geologic, mining, and regulatory factors that change the deposition scheme of combustible coal dust. This causes the atmosphere of a coal mine to have a variable rock dust-coal dust mixture at the time of ignition. To investigate the impact of this variable atmosphere, a …

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Dielectrophoretic Nanoparticle Propellant Injection With Plasmonic Acceleration, Jaykob Maser, Joshua Rovey Oct 2018

Dielectrophoretic Nanoparticle Propellant Injection With Plasmonic Acceleration, Jaykob Maser, Joshua Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We describe the concept of a dielectrophoretic propellant injector and its inclusion in a plasmonic-based, small-satellite propulsion system. Thrust is achieved by applying a plasmon generated non-uniform electromagnetic field, and corresponding dielectrophoretic force, to net-neutral nanoparticles.

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Fast Uncertainty Propagation Of Ultrasonic Testing Simulations For Mapod And Sensitivity Analysis, Xiaosong Du, Leifur Leifsson, Praveen Gurrala, Jiming Song, Slawomir Koziel Oct 2018

Fast Uncertainty Propagation Of Ultrasonic Testing Simulations For Mapod And Sensitivity Analysis, Xiaosong Du, Leifur Leifsson, Praveen Gurrala, Jiming Song, Slawomir Koziel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Model-assisted probability of detection (MAPOD) and sensitivity analysis (SA) are widelyused for measuring the reliability of nondestructive testing (NDT) systems., such as ultrasonictesting (UT), and understanding the effects of uncertainty parameters. In this work, a stochastic expansion-based metamodel is used in lieu of the physics-based NDT simulation model for efficient uncertainty propagation while keeping satisfactory accuracy. The proposed stochasticmetamodeling approach is demonstrated for MAPOD and SA on a benchmark case for UT simulations on a fused quartz block with a spherically-void defect. The proposed approach is compared with direct Monte Carlo sampling (MCS), and MCS with Kriging metamodels. The results …

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Multifidelity Modeling Of Ultrasonic Testing Simulations With Cokriging, Leifur Leifsson, Xiaosong Du, Slawomir Koziel Oct 2018

Multifidelity Modeling Of Ultrasonic Testing Simulations With Cokriging, Leifur Leifsson, Xiaosong Du, Slawomir Koziel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Multifidelity methods are introduced to the nondestructive evaluation (NDE) of measurement systems. In particular, Cokriging interpolation metamodels of physics-based ultrasonic testing (UT) simulation responses are utilized to accelerate the uncertainty propagation in model-assisted NDE. The proposed approach is applied to a benchmark test case of UT simulations and compared with the current state-of-the-art techniques. The results show that Cokriging captures the physics of the problem well and is able to reduce the computational burden by over one order of magnitude compared to the state of the art. To the best of the author's knowledge, this the first time multifidelity methods …

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Impulsive Dynamics And Control Of The Inertia-Wheel Pendulum, Nilay Kant, Ranjan Mukherjee Oct 2018

Impulsive Dynamics And Control Of The Inertia-Wheel Pendulum, Nilay Kant, Ranjan Mukherjee

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The dynamics of the inertia-wheel pendulum, when subjected to impulsive inputs, can be described by algebraic equations. Optimal sequences of these inputs, that minimize their infinity norm, are designed for rest-to-rest maneuvers. The results are applied to the well-studied swing-up problem, and high-gain feedback is used for continuous approximation of the inputs and simulation of the impulsive dynamics. Analytical and simulation results establish a direct link between high wheel velocities during swing-up and control strategies that take the pendulum directly to the upright configuration. They also indicate that optimal trajectories resemble those of energy-based controllers and can be designed to …

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Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson Oct 2018

Explosive Dust Test Vessel Comparison Using Pulverized Pittsburgh Coal, Jacob Miller, Jay Schafler, Phillip R. Mulligan, Robert Eades, Kyle A. Perry, Catherine E. Johnson

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Explosions of coal dust are a major safety concern within the coal mining industry. The explosion and subsequent fires caused by coal dust can result in significant property damage, loss of life in underground coal mines and damage to coal processing facilities. The United States Bureau of Mines conducted research on coal dust explosions until 1996 when it was dissolved. In the following years, the American Society for Testing and Materials (ASTM) developed a test standard, ASTM E1226, to provide a standard test method characterizing the “explosibility” of particulate solids of combustible materials suspended in air. The research presented herein …

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Effects Of Nearwall Modeling In The Improved-Delayed-Detached-Eddy-Simulation (Iddes) Methodology, Rohit Saini, Nader Karimi, Lian Duan, Amsini Sadiki, Amirfarhang Mehdizadeh Oct 2018

Effects Of Nearwall Modeling In The Improved-Delayed-Detached-Eddy-Simulation (Iddes) Methodology, Rohit Saini, Nader Karimi, Lian Duan, Amsini Sadiki, Amirfarhang Mehdizadeh

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The present study aims to assess the effects of two different underlying RANS models on overall behavior of the IDDES methodology when applied to different flow configurations ranging from fully attached (plane channel flow) to separated flows (periodic hill flow). This includes investigating prediction accuracy of first and second order statistics, response to grid refinement, grey area dynamics and triggering mechanism. Further, several criteria have been investigated to assess reliability and quality of the methodology when operating in scale resolving mode. It turns out that irrespective of the near wall modeling strategy, the IDDES methodology does not satisfy all criteria …

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Command Governor-Based Adaptive Control For Dynamical Systems With Matched And Unmatched Uncertainties, Metehan Yayla, Ehsan Arabi, Ali Turker Kutay, Tansel Yucelen Aug 2018

Command Governor-Based Adaptive Control For Dynamical Systems With Matched And Unmatched Uncertainties, Metehan Yayla, Ehsan Arabi, Ali Turker Kutay, Tansel Yucelen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, we propose a command governor-based adaptive control architecture for stabilizing uncertain dynamical systems with not only matched but also unmatched uncertainties and achieving the desired command following performance of a user-defined subset of the accessible states. In our proposed solution, online least-squares solutions for the matched and unmatched parameters are obtained through integration method and they are employed in the adaptive control framework. Specifically, the matched uncertainty is identified and its effect upon the system behavior is entirely attenuated. Moreover, using the unmatched uncertainty approximation obtained through radial basis function neural networks, the command governor signal is …

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Fast Prediction Of Thermal Distortion In Metal Powder Bed Fusion Additive Manufacturing: Part 1, A Thermal Circuit Network Model, Hao Peng, Morteza Ghasri-Khouzani, Shan Gong, Ross Attardo, Pierre Ostiguy, Bernice Aboud Gatrell, Joseph Budzinski, Charles Tomonto, Joel Neidig, M. Ravi Shankar, Richard Billo, David B. Go, David Hoelzle Aug 2018

Fast Prediction Of Thermal Distortion In Metal Powder Bed Fusion Additive Manufacturing: Part 1, A Thermal Circuit Network Model, Hao Peng, Morteza Ghasri-Khouzani, Shan Gong, Ross Attardo, Pierre Ostiguy, Bernice Aboud Gatrell, Joseph Budzinski, Charles Tomonto, Joel Neidig, M. Ravi Shankar, Richard Billo, David B. Go, David Hoelzle

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The additive manufacturing (AM) process metal powder bed fusion (PBF) can quickly produce complex parts with mechanical properties comparable to wrought materials. However, thermal stress accumulated during PBF induces part distortion, potentially yielding parts out of specification and frequently process failure. This manuscript is the first of two companion manuscripts that introduce a computationally efficient distortion and stress prediction algorithm that is designed to drastically reduce compute time when integrated in to a process design optimization routine. In this first manuscript, we introduce a thermal circuit network (TCN) model to estimate the part temperature history during PBF, a major computational …

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Fast Prediction Of Thermal Distortion In Metal Powder Bed Fusion Additive Manufacturing: Part 2, A Quasi-Static Thermo-Mechanical Model, Hao Peng, Morteza Ghasri-Khouzani, Shan Gong, Ross Attardo, Pierre Ostiguy, Ronald B. Rogge, Bernice Aboud Gatrell, Joseph Budzinski, Charles Tomonto, Joel Neidig, M. Ravi Shankar, Richard Billo, David B. Go, David Hoelzle Aug 2018

Fast Prediction Of Thermal Distortion In Metal Powder Bed Fusion Additive Manufacturing: Part 2, A Quasi-Static Thermo-Mechanical Model, Hao Peng, Morteza Ghasri-Khouzani, Shan Gong, Ross Attardo, Pierre Ostiguy, Ronald B. Rogge, Bernice Aboud Gatrell, Joseph Budzinski, Charles Tomonto, Joel Neidig, M. Ravi Shankar, Richard Billo, David B. Go, David Hoelzle

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The additive manufacturing (AM) process metal powder bed fusion (PBF) can quickly produce complex parts with mechanical properties comparable to that of wrought materials. However, thermal stress accumulated during Metal PBF may induce part distortion and even cause failure of the entire process. This manuscript is the second part of two companion manuscripts that collectively present a part-scale simulation method for fast prediction of thermal distortion in Metal PBF. The first part provides a fast prediction of the temperature history in the part via a thermal circuit network (TCN) model. This second part uses the temperature history from the TCN …

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Molecular Dynamics Simulation Study On The Possible Factors Affecting Stability Of Ods Steel, M. Mustafa Azeem, Zhongyu Li, Qingyu Wang, Abid Hussian Jul 2018

Molecular Dynamics Simulation Study On The Possible Factors Affecting Stability Of Ods Steel, M. Mustafa Azeem, Zhongyu Li, Qingyu Wang, Abid Hussian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Oxide-dispersed-strengthened (ODS) steel has excellent mechanical, thermodynamic and radiation resistant properties, which makes it an important candidate material for high-Temperature reactors applications. Radiation stability of oxide is very important to study at the atomic level. In present case molecular dynamics (MD) simulation is used to study stabilities of Y2O3 particles in ODS steel as a function of particle sizes. The size dependence is obvious for particle sizes larger than 2.8 nm. Furthermore, the stabilities depend on charges of Y and O atoms.

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Tutorial: Determination Of Thermal Boundary Resistance By Molecular Dynamics Simulations, Zhi Liang, Ming Hu May 2018

Tutorial: Determination Of Thermal Boundary Resistance By Molecular Dynamics Simulations, Zhi Liang, Ming Hu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Due to the High Surface-To-Volume Ratio of Nanostructured Components in Microelectronics and Other Advanced Devices, the Thermal Resistance at Material Interfaces Can Strongly Affect the overall Thermal Behavior in These Devices. Therefore, the Thermal Boundary Resistance, R, Must Be Taken into Account in the Thermal Analysis of Nanoscale Structures and Devices. This Article is a Tutorial on the Determination of R and the Analysis of Interfacial Thermal Transport Via Molecular Dynamics (MD) Simulations. in Addition to Reviewing the Commonly Used Equilibrium and Non-Equilibrium MD Models for the Determination of R, We Also Discuss Several MD Simulation Methods Which Can Be …

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Research Of A Non-Linearity Control Algorithm For Uav Target Tracking Based On Fuzzy Logic Systems, Chaoying Pei, Jingjuan Zhang, Xueyun Wang, Qian Zhang May 2018

Research Of A Non-Linearity Control Algorithm For Uav Target Tracking Based On Fuzzy Logic Systems, Chaoying Pei, Jingjuan Zhang, Xueyun Wang, Qian Zhang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Target tracking is one of the most widely used applications of UAVs and visual based tracking is the main method for non-cooperative tracking. In non-cooperative tracking missions, the UAV circles around the target and the gimbal rotates to keep the optic axis of the onboard camera pointing to the target. Compared with the biaxial gimbal, the single-axis gimbal system consists of only one torque motor, forming a great lightweight sensor suite, which also increases the requirement of the control accuracy. In the process of tracking moving target using a UAV with single-axis gimbal, there are still several challenges: (1) The …

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Model-Assisted Probability Of Detection Of Flaws In Aluminum Blocks Using Polynomial Chaos Expansions, Xiaosong Du, Leifur Leifsson, Robert Grandin, William Meeker, Ronald Roberts, Jiming Song Apr 2018

Model-Assisted Probability Of Detection Of Flaws In Aluminum Blocks Using Polynomial Chaos Expansions, Xiaosong Du, Leifur Leifsson, Robert Grandin, William Meeker, Ronald Roberts, Jiming Song

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Probability of detection (POD) is widely used for measuring reliability of nondestructive testing (NDT) systems. Typically, POD is determined experimentally, while it can be enhanced by utilizing physics-based computational models in combination with model-assisted POD (MAPOD) methods. With the development of advanced physics-based methods, such as ultrasonic NDT testing, the empirical information, needed for POD methods, can be reduced. However, performing accurate numerical simulations can be prohibitively time-consuming, especially as part of stochastic analysis. In this work, stochastic surrogate models for computational physics-based measurement simulations are developed for cost savings of MAPOD methods while simultaneously ensuring sufficient accuracy. The stochastic …

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Direct Metal Laser-Sintered Stainless Steel: Comparison Of Microstructure And Hardness Between Different Planes, M. Ghasri-Khouzani, H. Peng, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar Apr 2018

Direct Metal Laser-Sintered Stainless Steel: Comparison Of Microstructure And Hardness Between Different Planes, M. Ghasri-Khouzani, H. Peng, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Microstructural analysis and micro-hardness measurements were performed on different planes of 316L stainless steel fabricated by direct metal laser sintering (DMLS) technique. A fine cellular network was observed within the steel microstructure, where morphology of most cells changed from columnar on XZ-plane (vertical section) to equiaxed on XY-plane (horizontal section). Correspondingly, morphology of most grains was found to alter from columnar for the XZ-plane to equiaxed in the case of the XY-plane. Moreover, X-ray diffraction (XRD) analysis revealed a fully austenitic structure for both the planes. The average micro-hardness value for the XZ-plane and XY-plane was insignificantly (≈ 3%) different, …

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Classical Molecular Dynamics Study For Defect Sink Behavior In Oxide Dispersed Strengthened Alloys, M. Mustafa Azeem, Zhongyu Li, Qingyu Wang, Qazi Muhammad Nouman Amjad, Muhammad Zubair, O. M.H. Ahmed Mar 2018

Classical Molecular Dynamics Study For Defect Sink Behavior In Oxide Dispersed Strengthened Alloys, M. Mustafa Azeem, Zhongyu Li, Qingyu Wang, Qazi Muhammad Nouman Amjad, Muhammad Zubair, O. M.H. Ahmed

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Oxide Dispersed Strengthened (ODS) alloys are considered as a potential candidate for future generation reactors and can even be graded as better radiation resistant materials than the ones already in use. Molecular dynamics (MD) simulation study for defect sinks properties of ODS alloys have been investigated at 700K using LAMMPS (Atomic/Molecular massively parallel simulator software. SRIM (stopping range of ions in matter) code was used to see the approximate range of the ions and damage cascade profile. It has been observed that the oxide particle attracts vacancies/interstitials produced in the base matrix near the interface. The modeled structure looked amorphous …

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Ultra-Broadband Infrared Absorption By Tapered Hyperbolic Multilayer Waveguides, Huixu Deng, Cherian J. Mathai, Shubhra Gangopadhyay, Jie Gao, Xiaodong Yang Mar 2018

Ultra-Broadband Infrared Absorption By Tapered Hyperbolic Multilayer Waveguides, Huixu Deng, Cherian J. Mathai, Shubhra Gangopadhyay, Jie Gao, Xiaodong Yang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Ultra-broadband strong absorption over 92% covering the infrared wavelength range of 1 ~ 6μm is demonstrated by using the tapered hyperbolic Au-SiO2 multilayer waveguides on glass substrates. Such broadband absorption is formed by the stop-light modes at various wavelengths located at different waveguide widths. A planar hyperbolic waveguide model is built to determine the stop-light modes by considering both forward and backward guided modes. The stop-light modes located inside the Au-SiO2 multilayer waveguide are simulated at the absorption peaks by reducing the Au loss. Tapered multilayer waveguides with varying top widths are further simulated, fabricated and measured, indicating …

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Wavelength-Selective Mid-Infrared Metamaterial Absorbers With Multiple Tungsten Cross Resonators, Zhigang Li, Liliana Stan, David A. Czaplewski, Xiaodong Yang, Jie Gao Mar 2018

Wavelength-Selective Mid-Infrared Metamaterial Absorbers With Multiple Tungsten Cross Resonators, Zhigang Li, Liliana Stan, David A. Czaplewski, Xiaodong Yang, Jie Gao

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Wavelength-selective metamaterial absorbers in the mid-infrared range are demonstrated by using multiple tungsten cross resonators. By adjusting the geometrical parameters of cross resonators in single-sized unit cells, near-perfect absorption with single absorption peak tunable from 3.5 µm to 5.5 µm is realized. The combination of two, three, or four cross resonators of different sizes in one unit cell enables broadband near-perfect absorption at mid-infrared range. The obtained absorption spectra exhibit omnidirectionality and weak dependence on incident polarization. The underlying mechanism of near-perfect absorption with cross resonators is further explained by the optical mode analysis, dispersion relation and equivalent RLC circuit …

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Numerical Study Of Lateral Migration Of Elliptical Magnetic Microparticles In Microchannels In Uniform Magnetic Fields, Jie Zhang, Cheng Wang Mar 2018

Numerical Study Of Lateral Migration Of Elliptical Magnetic Microparticles In Microchannels In Uniform Magnetic Fields, Jie Zhang, Cheng Wang

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This work reports numerical investigation of lateral migration of a paramagnetic microparticle of an elliptic shape in a plane Poiseuille flow of a Newtonian fluid under a uniform magnetic field by direct numerical simulation (DNS). A finite element method (FEM) based on the arbitrary Lagrangian–Eulerian (ALE) approach is used to study the effects of strength and direction of the magnetic field, particle–wall separation distance and particle shape on the lateral migration. The particle is shown to exhibit negligible lateral migration in the absence of a magnetic field. When the magnetic field is applied, the particle migrates laterally. The migration direction …

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Characterizing The Influence Of Matrix Ductility On Damage Phenomenology In Continuous Fiber-Reinforced Thermoplastic Laminates Undergoing Quasi-Static Indentation, A. Yudhanto, H. Wafai, G. Lubineau, R. Yaldiz, N. Verghese Feb 2018

Characterizing The Influence Of Matrix Ductility On Damage Phenomenology In Continuous Fiber-Reinforced Thermoplastic Laminates Undergoing Quasi-Static Indentation, A. Yudhanto, H. Wafai, G. Lubineau, R. Yaldiz, N. Verghese

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The use of thermoplastic matrix was known to improve the impact properties of laminated composites. However, different ductility levels can exist in a single family of thermoplastic matrix, and this may consequently modify the damage phenomenology of thermoplastic composites. This paper focuses on the effect of matrix ductility on the out-of-plane properties of thermoplastic composites, which was studied through quasi-static indentation (QSI) test that may represent impact problem albeit the speed difference. We evaluated continuous glass-fiber reinforced polypropylene thermoplastic composites (GFPP), and selected homopolymer PP and copolymer PP that represent ductile and less ductile matrices, respectively. Several cross-ply laminates were …

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Molecular Simulation Of Steady-State Evaporation And Condensation In The Presence Of A Non-Condensable Gas, Zhi Liang, Pawel Keblinski Feb 2018

Molecular Simulation Of Steady-State Evaporation And Condensation In The Presence Of A Non-Condensable Gas, Zhi Liang, Pawel Keblinski

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Using Molecular Dynamics Simulations, We Study Evaporation and Condensation of Fluid Ar in the Presence of a Non-Condensable Ne Gas in a Nanochannel. the Evaporation and Condensation Are Driven by the Temperature Difference, ΔTL, between the Evaporating and Condensing Liquid Surfaces. the Steady-State Evaporation and Condensation Fluxes (JMD) Are Also Affected by the Ne Concentration, ΡNe, and the Nanochannel Length. We Find that Across a Wide Range of ΔTL and ΡNe, JMD is in Good Agreement with the Prediction from Stefan's Law and from Schrage Relationships. Furthermore, for ΔTL Less Than ∼20% of the Absolute Average Temperature, We Find that …

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Nano-Graphene Oxide And Vitamin D Delivery, Reza Mahdavi, Mehran Solati-Hashjin, Meisam Omidi, Arash Khojasteh, Fateme Fayyazbakhsh Jan 2018

Nano-Graphene Oxide And Vitamin D Delivery, Reza Mahdavi, Mehran Solati-Hashjin, Meisam Omidi, Arash Khojasteh, Fateme Fayyazbakhsh

Mechanical and Aerospace Engineering Faculty Research & Creative Works

One of the Most Interesting and Recent Insights into Biomimetic Scaffold Nano-Biomaterial is Smart Scaffolding with Targeted Drug Delivery Ability. in Recent Decades, the Use of Graphene-Based Materials, Such as Nano-Graphene Oxide (NGO), as a Drug Carrier with Amphiphilic Properties, Has Attracted Considerable Attention of Scientists and Researchers in This Field. in Addition, One of the Important Global Problems is Increased Vitamin D Deficiency, Particularly in Pregnant and Postmenopausal Women. Therefore, in This Work, by Considering Hydrophobic Properties of Vitamin D, We Attempted to Examine its Loading and Release Both in the Presence of Surfactant and Surfactant-Free NGO-Aqueous Solution. at …

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Multitarget Tracking And Terrain-Aided Navigation Using Square-Root Consider Filters, James Samuel Mccabe Jan 2018

Multitarget Tracking And Terrain-Aided Navigation Using Square-Root Consider Filters, James Samuel Mccabe

Doctoral Dissertations

"Filtering is a term used to describe methods that estimate the values of partially observed states, such as the position, velocity, and attitude of a vehicle, using current observations that are corrupted due to various sources, such as measurement noise, transmission dropouts, and spurious information. The study of filtering has been an active focus of research for decades, and the resulting filters have been the cornerstone of many of humankind's greatest technological achievements. However, these achievements are enabled principally by the use of specialized techniques that seek to, in some way, combat the negative impacts that processor roundoff and truncation …

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Effects Of Terrain-Based Altimetry On Navigation Performance, Kenneth Michael Kratzer Jan 2018

Effects Of Terrain-Based Altimetry On Navigation Performance, Kenneth Michael Kratzer

Masters Theses

"Navigation filters used during an entry, descent, and landing scenario often receive measurements related to the terrain over which the vehicle is traversing. Models of the terrain can be presented in varying degrees of fidelity, providing increasingly realistic and accurate models of the surface. While it is ideal to provide the filter with the most realistic model possible, the performance is limited by the strict nature of the real time scenario. Therefore, it is of interest to determine what level of fidelity is necessary to achieve an accurate filtering solution. Determining how best to incorporate terrain-related data into navigation solutions …

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Quantifying On-Orbit Performance Of Cubesat Micropropulsion Systems By Observing Orbital Element Variations, Bradyn William Morton Jan 2018

Quantifying On-Orbit Performance Of Cubesat Micropropulsion Systems By Observing Orbital Element Variations, Bradyn William Morton

Masters Theses

"The Advanced Propulsion Experiment mission in development by the Missouri University of Science and Technology's satellite research team (M-SAT) is a technology demonstration mission of a multi-mode propulsion system. The true test of any satellite propulsion system is the on-orbit performance. The purpose of this research is to develop methods for quantifying the on-orbit performance of the multi-mode propulsion system. This performance can be determined by observing the small variations in the orbital element parameters and using a differential corrector with the Gauss Variation of Parameter equations. Furthermore, this research could be used to determine and quantify a propulsion system's …

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Developing Computational Models For Pulsed-Inductive Plasma Formation, Zachary Aaron Gill Jan 2018

Developing Computational Models For Pulsed-Inductive Plasma Formation, Zachary Aaron Gill

Masters Theses

"Pulsed-inductive discharges are a common method of producing a plasma. They provide a mechanism for quickly and efficiently generating a large volume of plasma for rapid use and are seen in applications including propulsion, fusion power, and high-power lasers. However, some common designs see a delayed response time due to the plasma forming when the magnitude of the magnetic field in the device is at a minimum. New designs are difficult to evaluate due to the amount of time needed to construct a new geometry and the high monetary cost of changing the power generation circuit. To more quickly evaluate …

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Square-Root Consider Filters With Hyperbolic Householder Reflections, James S. Mccabe, Kyle J. De Mars Jan 2018

Square-Root Consider Filters With Hyperbolic Householder Reflections, James S. Mccabe, Kyle J. De Mars

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Maintaining positive definiteness of a filter's error covariance estimate is of paramount importance to any stable and reliable estimation scheme. Two widely used methods for protecting a filter from loss of positive-definiteness are that of consider filtering and square-root filtering. Despite their widespread use in estimation applications, a filtering methodology that combines the two techniques has yet to be presented in a unified, streamlined architecture. This paper develops a new approach to square-root filtering using hyperbolic Householder reflections. A specialization of the method is considered to permit computationally efficient applications, and a numerical example pertaining to a ballistic reentry is …

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Set-Theoretic Model Reference Adaptive Control Of A Generic Transport Model, Ehsan Arabi, Tansel Yucelen, Nhan T. Nguyen Jan 2018

Set-Theoretic Model Reference Adaptive Control Of A Generic Transport Model, Ehsan Arabi, Tansel Yucelen, Nhan T. Nguyen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper illustrates an application of a recently developed set-theoretic model reference adaptive control architecture on a generic transport model developed by NASA. The set- theoretic model reference adaptive control allows the system error bound between the state of an uncertain dynamical system and the state of a given reference model to be less than a-priori, user-defined worst-case performance bound. Thus, it has the capability to enforce strict performance guarantees to the adaptively controlled uncertain dynamical systems. specifically, after designing set-theoretic adaptive controllers for both longitudinal and lateral-directional dynamics here, the efficacy of this architecture is illustrated on the NASA …

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