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Software Health Management With Bayesian Networks, Johann Schumann, Timmy Mbaya, Ole J. Mengshoel, Knot Pipatsrisawat, Ashok Srivastava, Arthur Choi, Adnan Darwiche 2013 Carnegie Mellon University

Software Health Management With Bayesian Networks, Johann Schumann, Timmy Mbaya, Ole J. Mengshoel, Knot Pipatsrisawat, Ashok Srivastava, Arthur Choi, Adnan Darwiche

Ole J Mengshoel

Software Health Management (SWHM) is an emerging field which addresses the critical need to detect, diagnose, predict, and mitigate adverse events due to software faults and failures. These faults could arise for numerous reasons including coding errors, unanticipated faults or failures in hardware, or problematic interactions with the external environment. This paper demonstrates a novel approach to software health management based on a rigorous Bayesian formulation that monitors the behavior of software and operating system, performs probabilistic diagnosis, and provides information about the most likely root causes of a failure or software problem. Translation of the Bayesian network model into …


Open And Openorbiter: A Needs-Responsive Solution For The Small Satellite Community, Jeremy Straub, Atif Mohammad 2013 SelectedWorks

Open And Openorbiter: A Needs-Responsive Solution For The Small Satellite Community, Jeremy Straub, Atif Mohammad

Jeremy Straub

The Open Prototype for Educational NanoSats (OPEN) is an initiative launched at the University of North Dakota, as a public service to the nation and the world. The OPEN team is working to create a design, set of implementation instructions and a testing plan for a 1-U CubeSat (which can also serve as a basis for a 2-U or 3-U CubeSat with limited modifications). These will be made publically available to facilitate the low-cost implementation of CubeSat programs at other institutions. The target of the designs is to allow fabrication with a parts budget of approximately $5,000. This is, thus, …


Stemsat: An Iss Cubesat Program Based On Spare Parts, Anders Nervold, Josh Berk, Jeremy Straub 2013 SelectedWorks

Stemsat: An Iss Cubesat Program Based On Spare Parts, Anders Nervold, Josh Berk, Jeremy Straub

Jeremy Straub

With the national government’s focus on driving STEM-education, it is important to provide hands-on ave-nues where students can engage with, and accumulate ex-perience working directly with projects within their fields of interest. The Student Technology Emersion Satellite (STEMSat), provides an avenue for students to become in-volved in CubeSat design and development with only mi-nor hardware and monetary resources, and without being dependent on a launch.

STEMSats are CubeSat satellites that are created from spare parts, residual tools and equipment, obsolete mate-rials, and other types of trash aboard the ISS. A list of all the excess items available for such a …


Enabling Rapid Conceptual Design Using Geometry-Based Multi-Fidelity Models In Vsp, Joel Brian Belben 2013 California Polytechnic State University, San Luis Obispo

Enabling Rapid Conceptual Design Using Geometry-Based Multi-Fidelity Models In Vsp, Joel Brian Belben

Master's Theses

The purpose of this work is to help bridge the gap between aircraft conceptual design and analysis. Much work is needed, but distilling essential characteristics from a design and collecting them in an easily accessible format that is amenable to use by inexpensive analysis tools is a significant contribution to this goal. Toward that end, four types of reduced-fidelity or degenerate geometric representations have been defined and implemented in VSP, a parametric geometry modeler. The four types are degenerate surface, degenerate plate, degenerate stick, and degenerate point, corresponding to three-, two-, one-, and zero- dimensional representations of underlying geometry, respectively. …


Pseudolite Architecture And Performance Analysis For The Faa's Nextgen Airspace, Joseph A . Czabaranek 2013 Air Force Institute of Technology

Pseudolite Architecture And Performance Analysis For The Faa's Nextgen Airspace, Joseph A . Czabaranek

Theses and Dissertations

By 2025 the FAA plans to have fully implemented its NextGen Airspace design. NextGen takes advantage of modern positioning technologies as well as automation, data sharing, and display technologies that will allow more efficient use of our ever busier National Airspace (NAS). A key element of NextGen is the transition from surveillance RADAR providing aircraft separation and navigation to the use of the GPS and Automatic Dependent Surveillance Broadcast (ADS-B). ADS-B couples the precision of the GPS with networked ground and airborne receivers to provide precise situational awareness to pilots and controllers. The result is increased safety, capacity, and access …


Effects Of Stereoscopic 3d Digital Radar Displays On Air Traffic Controller Performance, Jason G. Russi 2013 Air Force Institute of Technology

Effects Of Stereoscopic 3d Digital Radar Displays On Air Traffic Controller Performance, Jason G. Russi

Theses and Dissertations

Air traffic controllers are responsible for directing air traffic based upon decisions made from traffic activity depicted on 2Dimensional (2D) radar displays. Controllers must identify aircraft and detect potential conflicts while simultaneously developing and executing plans of action to ensure safe separation is maintained. With a nearly 100% increase in traffic expected within the next decade (FAA, 2012a), controllers' abilities to rapidly interpret spacing and maintain awareness for longer durations with increased workload will become increasingly imperative to safety. The current display design spatially depicts an aircraft's position relative to the controller's airspace as well as speed, altitude, and direction …


Supplementary Computer Generated Cueing To Enhance Air Traffic Controller Efficiency, Laurienne Cibelle Rodrigues de Assis Santana 2013 Air Force Institute of Technology

Supplementary Computer Generated Cueing To Enhance Air Traffic Controller Efficiency, Laurienne Cibelle Rodrigues De Assis Santana

Theses and Dissertations

Air traffic controllers are often required to simultaneously communicate with several aircraft over multiple radio frequencies. As a result, during peak loading, it is common for the controller to receive multiple concurrent communications, each from a different aircraft, making it difficult to discern audio messages received from multiple pilots simultaneously. To address this problem, a modified air traffic control (ATC) interface was prototyped with the goal of increasing controller-to-pilot communication efficiency. This prototype included supplementary text cueing which was provided by a hypothetical automated text to speech system in an on-screen text box for controller reference in the event of …


Development Of Autonomous Optimal Cooperative Control In Relay Rover Configured Small Unmanned Aerial Systems, Timothy J. Shuck 2013 Air Force Institute of Technology

Development Of Autonomous Optimal Cooperative Control In Relay Rover Configured Small Unmanned Aerial Systems, Timothy J. Shuck

Theses and Dissertations

This thesis documents the research effort to develop, integrate and implement the system hardware and the software necessary to validate the Air Force Institute of Technology's theoretical advances in small unmanned aerial systems (SUAS) cooperative control. The end state objective of the research effort was to flight test an autonomous control algorithm on a communication relay unmanned aerial vehicle (UAV) that was actively relaying data to and from a rover UAV. The relay UAV is one part of a SUAS designed to utilize cooperative control to extend the effective line-of-sight operating range for a rover UAV. An algorithm is integrated …


Finite Element Simulation Of Wind Turbine Aerodynamics: Validation Study Using Nrel Phase Vi Experiment, Ming-Chen Hsu, Ido Akkerman, Yuri Bazilevs 2013 University of California, San Diego

Finite Element Simulation Of Wind Turbine Aerodynamics: Validation Study Using Nrel Phase Vi Experiment, Ming-Chen Hsu, Ido Akkerman, Yuri Bazilevs

Ming-Chen Hsu

A validation study using the National Renewable Energy Laboratory (NREL) Phase VI wind turbine is presented. The aerodynamics simulations are performed using the finite element arbitrary Lagrangian–Eulerian–variational multiscale formulation augmented with weakly enforced essential boundary conditions. In all cases, the rotor is assumed to be rigid and its rotation is prescribed. The rotor-only simulations are performed for a wide range of wind conditions, and the computational results compare favorably with the experimental findings in all cases. The sliding-interface method is adopted for the simulation of the full wind turbine configuration. The full-wind-turbine simulations capture the blade–tower interaction effect, and the …


Exposing Multiple User-Specific Data Denominated Products From A Single Small Satellite Data Stream, Atif F. Mohammad,, Emanuel Grant, Jeremy Straub, Ronald Marsh, Scott Kerlin 2013 SelectedWorks

Exposing Multiple User-Specific Data Denominated Products From A Single Small Satellite Data Stream, Atif F. Mohammad,, Emanuel Grant, Jeremy Straub, Ronald Marsh, Scott Kerlin

Jeremy Straub

This paper presents a research work on small satellite data stream and related distribution to associated stakeholders, which is a field that needs to get explored in more detail. The algorithm that is presented to extract USDDP (User-Specific Data Denominated Products) is a self managing body, which will be within as Open Space Box environment or OSBE as a novel idea. It contains an individual stream transmitted by the small satellite, which later is to be converted into USDDP. The context defined here deals with area in detail. Contexts are vitally important because they control, influence and affect everything within …


The Open Prototype For Educational Nanosats: Fixing The Other Side Of The Small Satellite Cost Equation, Josh Berk, Jeremy Straub, David Whalen 2013 SelectedWorks

The Open Prototype For Educational Nanosats: Fixing The Other Side Of The Small Satellite Cost Equation, Josh Berk, Jeremy Straub, David Whalen

Jeremy Straub

Government supported nano-satellite launch programs and emerging commercial small satellite launch services are reducing the cost of access to space for educational and other CubeSat projects. The cost and complexity of designing and building these satellites remains a vexing complication for many would be CubeSat aspirants. The Open Prototype for Educational NanoSats (OPEN), a proposed nano-satellite development platform, is described in this paper. OPEN endeavors to reduce the costs and risks associated with educational, government and commercial nano-satellite development. OPEN provides free and publicly available plans for building, testing and operating a versatile, low-cost satellite, based on the standardized CubeSat …


Smore Revision: Ignition And User Interface, Arash Mehrparvar 2013 California Polytechnic State University, San Luis Obispo

Smore Revision: Ignition And User Interface, Arash Mehrparvar

Aerospace Engineering

The Static Methanol Oxygen Rocket Engine (SMORE) has undergone several revisions since its inception. This latest revision aimed to increase startup reliability and user safety in the operation of the rocket. The implementation of maintenance procedures, safeguards in the ignition system, as well as construction of a new control box and redesign of the igniter itself have accomplished these goals while keeping costs down and without modifying the current rocket setup. Startup reliability has increased drastically, so long as all other rocket setup procedures are followed properly. 250 subsequent firings of the rocket have proven an igniter reliability of more …


The International Trafficking In Arms Regulations: Precluding Innovation In Academic Spacecraft Engineering — Or Are They?, Jeremy Straub, Joe Vacek 2013 SelectedWorks

The International Trafficking In Arms Regulations: Precluding Innovation In Academic Spacecraft Engineering — Or Are They?, Jeremy Straub, Joe Vacek

Jeremy Straub

Government regulations and uncertainty about their enforcement can be a significant barrier to innovation. In business, it is undesirable to consume time and other resources developing a product that cannot be sold or which requires navigating significant bureaucracy for each sale. In academ-ia, where limited funding is available prior to the submission of a grant pro-posal and receipt of an award, proposal-stage compliance costs can derail a project long before it begins. This paper reviews the International Traffick-ing in Arms Regulations (ITAR) and their impact on spacecraft research in academia, private research labs and industry. It reviews the exemptions available, …


Numerical Modeling And Characterization Of Vertically Aligned Carbon Nanotube Arrays, Johnson Joseph 2013 University of Kentucky

Numerical Modeling And Characterization Of Vertically Aligned Carbon Nanotube Arrays, Johnson Joseph

Theses and Dissertations--Mechanical Engineering

Since their discoveries, carbon nanotubes have been widely studied, but mostly in the forms of 1D individual carbon nanotube (CNT). From practical application point of view, it is highly desirable to produce carbon nanotubes in large scales. This has resulted in a new class of carbon nanotube material, called the vertically aligned carbon nanotube arrays (VA-CNTs). To date, our ability to design and model this complex material is still limited. The classical molecular mechanics methods used to model individual CNTs are not applicable to the modeling of VA-CNT structures due to the significant computational efforts required. This research is to …


Risk Analysis & Management In Student-Centered Spacecraft Development Projects, Jeremy Straub, Ronald Fevig, James Casler, Om Yadav 2013 SelectedWorks

Risk Analysis & Management In Student-Centered Spacecraft Development Projects, Jeremy Straub, Ronald Fevig, James Casler, Om Yadav

Jeremy Straub

Student involvement in any engineering project introduces an element of risk. This risk is particularly pronounced with small spacecraft projects, as a failure of the spacecraft on-orbit can result in a complete failure of the mission. However, student involvement in these projects is critical to allow research aims to be accomplished, in a university setting, and to train the next generation of spacecraft engineering professionals. The nature of risks posed by student involvement is discussed and a framework for assessing and mitigating these risks presented.


Trajectory Generation For Stair Ascent Walking Using Rayleigh Oscillator, T. Afzal, Andrew B. Wright, Kamran Iqbal 2013 University of Arkansas at Little Rock

Trajectory Generation For Stair Ascent Walking Using Rayleigh Oscillator, T. Afzal, Andrew B. Wright, Kamran Iqbal

Journal of the Arkansas Academy of Science

This paper describes a trajectory generation technique for stair-ascent walking. The knee, hip and ankle joint trajectory during stair ascent are generated using mutually coupled, nonlinear oscillators. The parameters of the oscillators are tuned using the harmonic balance method, which converts the nonlinear differential equations to a set of algebraic equations. Fourier analysis of data generated by stair-ascent walking is performed to extract the amplitude and the phase of the dominant frequency components for each joint trajectory. The solution for the oscillator is assumed to be a sinusoidal wave and then by harmonic balance method the parameters of the oscillator …


Isogeometric Fluid–Structure Interaction Analysis With Emphasis On Non-Matching Discretizations, And With Application To Wind Turbines, Y. Bazilevs, Ming-Chen Hsu, M. A. Scott 2012 University of California, San Diego

Isogeometric Fluid–Structure Interaction Analysis With Emphasis On Non-Matching Discretizations, And With Application To Wind Turbines, Y. Bazilevs, Ming-Chen Hsu, M. A. Scott

Ming-Chen Hsu

In this paper we develop a framework for fluid–structure interaction (FSI) modeling and simulation with emphasis on isogeometric analysis (IGA) and non-matching fluid–structure interface discretizations. We take the augmented Lagrangian approach to FSI as a point of departure. Here the Lagrange multiplier field is defined on the fluid–structure interface and is responsible for coupling of the two subsystems. Thus the FSI formulation does not rely on the continuity of the underlying function spaces across the fluid–structure interface in order to produce the correct coupling conditions between the fluid and structural subdomains. However, in deriving the final FSI formulation the interface …


Space Vehicle Testing, Charlotte Ann Belsick 2012 California Polytechnic State University, San Luis Obispo

Space Vehicle Testing, Charlotte Ann Belsick

Master's Theses

Requirement verification and validation is a critical component of building and delivering space vehicles with testing as the preferred method. This Master’s Project presents the space vehicle test process from planning through test design and execution. It starts with an overview of the requirements, validation, and verification. The four different verification methods are explained including examples as to what can go wrong if the verification is done incorrectly. Since the focus of this project is on test, test verification is emphasized. The philosophy behind testing, including the “why” and the methods, is presented. The different levels of testing, the test …


Stochastic Optimal Control In Nonlinear Systems, Celestin Nkundineza 2012 University of Nebraska - Lincoln

Stochastic Optimal Control In Nonlinear Systems, Celestin Nkundineza

Celestin Nkundineza

Stochastic control is an important area of research in engineering systems that undergo disturbances. Controlling individual states in such systems is critical. The present investigation is concerned with the application of the stochastic optimal control strategy developed by To (2010) and its implementation as well as providing computed results of linear and nonlinear systems under stationary and nonstationary random excitations. In the strategy the feedback matrix is designed based on the achievement of the objectives for individual states in the system through the application of the Lyapunov equation for the system. Each diagonal element in the gain or associated gain …


Microgravity Stowage System–A Random Access System For Deep Space Habitat Implementation, Clint Deerman, Drew Deerman 2012 University of Alabama in Huntsville

Microgravity Stowage System–A Random Access System For Deep Space Habitat Implementation, Clint Deerman, Drew Deerman

Von Braun Symposium Student Posters

No abstract provided.


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