Engineering Commons^™

Radiological Assay Of Burrowing Animals, James F. Pierce Mr, Jolyne Worthy Ms, Kip Wheeler Mrs, Evan Godbehere Mr

Chancellor’s Honors Program Projects

No abstract provided.

Utilization Of Caputo Fractional Derivative In Mhd Nanofluid Flow With Soret And Thermal Radiation Effects, Harshad Patel, Gopal Nanda

Applications and Applied Mathematics: An International Journal (AAM)

In existence of heat diffusion and thermal radiation, an analytical equation is found for unsteady MHD flow past an exponentially accelerating vertical plate in optically thick water based nanofluid. The governing equations are made dimensionless by similarity transformation. A definition of Caputo fractional derivative is applied to generalize governing system of partial differential equations. Laplace transform techniques are applied and obtained the analytical solutions of proposed problems. For a physical point of view, numerical results are obtained using MATLAB software and presented via graphs. From the results, it is concluded that magnetic fields tend to reduce velocity. It is also …

Remote Laboratory For Nuclear Security Education, Anthony R. Galindo, Craig Marianno

International Journal of Nuclear Security

Laboratory experiences for online students are very limited. To fill this gap, educators in the Department of Nuclear Engineering at Texas A&M University developed a series of radiation detection experiments for their remote students. Radiation detection is only one piece of nuclear security. The objective of the current research is to describe the development and execution of three online laboratories that investigate the basic application of physical security sensors that use light, ultrasonics, and heat to detect adversaries. This laboratory complements lecture material from the department’s Nuclear Security System and Design course. Using the Remote Desktop Application, students connect to …

Trumpet Directivity From A Rotating Semicircular Array, Samuel D. Bellows, Joseph E. Avila, Timothy W. Leishman

Directivity

The directivity function of a played musical instrument describes the angular dependence of its acoustic radiation and diffraction about the instrument, musician, and musician’s chair. Directivity influences sound in rehearsal, performance, and recording environments and signals in audio systems. Because high-resolution, spherically comprehensive measurements of played musical instruments have been unavailable in the past, the authors have undertaken research to produce and share such data for studies of musical instruments, simulations of acoustical environments, optimizations of microphone placements, and other applications. The authors acquired the data from repeated chromatic scales produced by a trumpet played at mezzo-forte in an anechoic …

Interaction Of Natural Convection And Real Gas Radiation Over A Vertical Flat Plate, Nathan Hale

Theses and Dissertations

This study explores natural convection heat transfer and fluid flow from a vertical plate in a radiating gas accounting for real gas spectral behavior. Finite volume techniques are used to solve the coupled nonlinear partial differential equations for mass, momentum, and energy conservation, while radiation transfer is modeled using the Discrete Ordinates finite volume finite angle method. Real gas spectral behavior is accounted for using the Rank Correlated Spectral Line Weighted-sum-of-gray-gases method. It is found that gas temperature and velocity are higher in the boundary layer, thickening the thermal and hydrodynamic boundary layers compared to the limiting case of pure …

Design And Simulation Of A Utility Oilfield Flare In Iraq/Kurdistan Region Using Cfd And Api-521 Methodology, Ahmed A. Maaroof, Joseph D. Smith, Mohammed H.S. Zangana

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper aims at reviewing and analyzing the operation and design of a utility flare in an oilfield in the Iraq/Kurdistan region. The flare supports a gas separation unit that separates 100 MMSCFD of natural gas from other liquid compounds in petroleum refining. The actual flare dimensions are 50 m high and 0.6 m diameter and works in summer where the crosswind speed is 9 m/s and a flow of 1.2 MMSCFD of treated natural gas is flaring through it. At the beginning, the flare design was performed using the API-521 recommended approach based on full operating capacity of the …

Fabrication, Measurements, And Modeling Of Semiconductor Radiation Detectors For Imaging And Detector Response Functions, Corey David Ahl

Doctoral Dissertations

In the first part of this dissertation, we cover the development of a diamond semiconductor alpha-tagging sensor for associated particle imaging to solve challenges with currently employed scintillators. The alpha-tagging sensor is a double-sided strip detector made from polycrystalline CVD diamond. The performance goals of the alpha-tagging sensor are 700-picosecond timing resolution and 0.5 mm spatial resolution. A literature review summarizes the methodology, goals, and challenges in associated particle imaging. The history and current state of alpha-tagging sensors, followed by the properties of diamond semiconductors are discussed to close the literature review. The materials and methods used to calibrate the …

Gamelan Gong Directivity Dataset, Samuel D. Bellows, Dallin T. Harwood, Kent L. Gee, Micah R. Shepherd

Directivity

No abstract provided.

Computational Tools For Modeling And Simulation Of Sooting Turbulent Non-Premixed Flames, Victoria B. Stephens

Theses and Dissertations

Turbulent combustion systems are physically complex processes that involve many interdependent phenomena---including turbulent fluid dynamics, multi-component mass transfer, convective and radiative heat transfer, and multiphase flow---that occur over a wide range of length and time scales. Modeling and simulation studies complement experimental work by implementing and validating models and providing predictive capabilities, but current software tools are often limited by a lack of standardization and best practices, non-robust implementation, or over-specialization. Some topics in combustion CFD research, notably radiative heat transfer and soot modeling, are critically underrepresented in simulation studies as a result of software limitations. This project establishes and …

Color Resolved Cherenkov Imaging Allows For Differential Signal Detection In Blood And Melanin Content, Vihan A. Wickramasinghe

Dartmouth College Master’s Theses

Cherenkov imaging in radiation therapy allows a video display of the irradiation beam on the patient’s tissue, for visualization of the treatment. High energy radiation from a linear accelerator (Linac) results in the production of spectrally-continuous broadband light inside tissue due to the Cherenkov effect; this light is then attenuated by tissue features from transport and exits from the delivery site. Progress with the development of color Cherenkov imaging has opened the possibility for some level of spectroscopic imaging of the light-tissue interaction and interpretation of the specific nature of the tissue being irradiated. Generally, there is a linear relationship …

Computational Models To Detect Radiation In Urban Environments: An Application Of Signal Processing Techniques And Neural Networks To Radiation Data Analysis, Jose Nicolas Gachancipa

Beyond: Undergraduate Research Journal

Radioactive sources, such as uranium-235, are nuclides that emit ionizing radiation, and which can be used to build nuclear weapons. In public areas, the presence of a radioactive nuclide can present a risk to the population, and therefore, it is imperative that threats are identified by radiological search and response teams in a timely and effective manner. In urban environments, such as densely populated cities, radioactive sources may be more difficult to detect, since background radiation produced by surrounding objects and structures (e.g., buildings, cars) can hinder the effective detection of unnatural radioactive material. This article presents a computational model …

Understanding The Radiation Effects On Fiber Optic Sensors, Sohel Rana

Boise State University Theses and Dissertations

In this dissertation, the effects of radiation (gamma, neutron or mixed gamma and neutron) on optical fiber sensors are studied and new techniques for real-time measurement of radiation-induced macroscopic changes in optical fibers are presented. It is crucial among the research and development efforts in the nuclear energy field to conduct experiments in Advanced Test Reactor (ATR) to support lifetime extension, novel fuels and materials development, better fuel management, and enhanced safety of existing as well as future nuclear power plants (NPP). Due to their unparalleled and unique advantages over traditional sensors, optical fiber sensors are deemed potential candidates for …

Near-Earth Ion Irradiation Effects On Functional Ceramic Materials: A Combined Experimental-Monte Carlo Approach, William J. Sands

All Theses

The near-Earth space radiation environment is a complex system that creates a harmful environment for materials to operate in. Motivated by the search for using optical defects as an indicator of radiation damage, five single-crystal functional ceramic materials were selected to undergo ion irradiation at conditions found in the near-Earth space environment. Due to the complex nature of ion irradiation effects in ceramic materials, a host of calculations and experimental characterization methods were used. Calculations using the 2013 SRIM code were used to evaluate the ion projected range and the type and number of defects (vacancies) created by ion irradiation. …

Partial Circuit Replication For Masking And Detecting Soft Errors In Sram-Based Fpgas, Andrew Mark Keller

Theses and Dissertations

Partial circuit replication is a soft error mitigation technique that uses redundant copies of a circuit to mask or detect the effects of soft errors. By masking or detecting the effect of soft errors on SRAM-based FPGAs, implemented circuits can be made more reliable. The technique is applied selectively, to only a portion of the components within a circuit. Partial application lowers the cost of implementation. The objective of partial circuit replication is to provide maximal benefit at limited or minimized cost. The greatest challenge of partial circuit replication is selecting which components within a circuit to replicate. This dissertation …

A Fault-Tolerant Optimal Message Routing Methodology For Cube-Nnected- Les Parallel Computers, Gene Eu Jan, Cheng-Hung Li, Yung-Yuan Chen, Shao-Wei Leu

Journal of Marine Science and Technology

A cube-connected-cycles (CCC) is a regular graph, suitable for constructing the interconnection network of parallel or multi-node computer systems. The CCC network possesses the features of symmetry, regularity, fault tolerance, and fixed degree of the network. Message delivery through an interconnection network sometimes fails due to processing node and/or link faults or simply because some processors are too busy to handle message transfer. To make a CCC-based parallel computer more resilient to node/link faults, this paper proposes an optimal routing method that guarantees to find a shortest path between the source and the destination nodes within a faulty CCC-based network …

A Computational Study Of Radiation Damage In Bilayer Silicon-Gold Structures, Cameron Hopper

Graduate Theses and Dissertations

Irradiation from sources such as nuclear reactors bombard materials with neutrons and heavy ions. The primary consequence of this irradiation is the displacement of atoms from their atomic structure. As the structure becomes damaged, the mechanical properties can change. Eventually, this can result in a failure due to embrittlement. This type of damage is hard to detect and can result in sudden, unexpected failure. Therefore, focusing on managing the consequences of irradiation has been a heavily researched topic. To manage irradiation, the focus is primarily to manage the voids and interstitials that appear during irradiation. Grain boundaries and amorphous regions …

Effects Of Memristive Synapse Radiation Interactions On Learning In Spiking Neural Networks, Sumedha Gandharava Dahl, Robert C. Ivans, Kurtis D. Cantley

Electrical and Computer Engineering Faculty Publications and Presentations

This study uses advanced modeling and simulation to explore the effects of external events such as radiation interactions on the synaptic devices in an electronic spiking neural network. Specifically, the networks are trained using the spike-timing-dependent plasticity (STDP) learning rule to recognize spatio-temporal patterns (STPs) representing 25 and 100-pixel characters. Memristive synapses based on a TiO₂ non-linear drift model designed in Verilog-A are utilized, with STDP learning behavior achieved through bi-phasic pre- and post-synaptic action potentials. The models are modified to include experimentally observed state-altering and ionizing radiation effects on the device. It is found that radiation interactions tend …

The Effects Of Ultraviolet Radiation On Aircraft Crewmember Health, Erin Johnston

Theses and Dissertations

Ultraviolet (UV) radiation and its effects on crewmember health will be evaluated by examining the variables that impact the intensity of UV radiation and the health concerns associated with this exposure. The purpose of this study was to (a) identify how Ultraviolet A (UVA) exposure is different in an aircraft cockpit when compared to the exposure at sea-level and (b) expose the adverse health impacts associated with an increased exposure of UVA radiation. This was accomplished through an examination of UV radiation and the variables that impact its effectiveness. After this analysis, the adverse health impacts experienced from UV radiation …

K-Wire Differentiation, Oluwadamilola Oluwadara, Lillian Maresco, Eunjung Lee, Michelle De Leon

Honors Theses

Kirschner Pins, known as K-wires, are smooth sharp stainless steel pins used in the field of orthopedics to stabilize bone fracture fragments in their correct position until they have fully healed. K-wires are most commonly used for comminuted metaphyseal fractures of the long bones, and fractures of smaller bones such as the phalanges. The wires are inserted into bone via a drill and the ends of the wire are bent and left outside of the body for easy removal once the bone has healed. The surgeon uses x-ray images to guide K-wire insertion, ensure proper internal alignment, and determine if …

Accuracy And Computational Cost Assessment Of Radiation Solvers For Combustion Simulations, Chloe David

Master's Theses (2009 -)

High-fidelity combustion simulations necessitate the accurate and efficient calculation of radiative heat transfer. A successful radiation calculation requires the use of a spectral model, which describes the variation of radiative properties across the entire electromagnetic spectrum, and a radiative transfer equation (RTE) solver, which solves the governing equation for radiation transport. Three primary categories of RTE solvers are the discrete ordinates method (DOM), the spherical harmonics method (SHM), and the photon Monte Carlo (PMC) method. The accuracy and computational cost of each type of RTE solver is compared in detail in this work. The PMC RTE solver is considered the …

Comparing Radiation Shielding Potential Of Liquid Propellants To Water For Application In Space, John Czaplewski

Master's Theses

The radiation environment in space is a threat that engineers and astronauts need to mitigate as exploration into the solar system expands. Passive shielding involves placing as much material between critical components and the radiation environment as possible. However, with mass and size budgets, it is important to select efficient materials to provide shielding. Currently, NASA and other space agencies plan on using water as a shield against radiation since it is already necessary for human missions. Water has been tested thoroughly and has been proven to be effective. Liquid propellants are needed for every mission and also share similar …

Electromagnetic Pollution Alert: Microwave Radiation And Absorption In Human Organs And Tissues, Nantakan Wongkasem

Electrical and Computer Engineering Faculty Publications and Presentations

Electromagnetic radiation from communication and electronic devices, networks, systems and base stations has drawn concern due to excessive global usage with increasing power and operating frequency level. Numerous previous researches only focus on how the radiation from certain frequency ranges of particular devices could harm specific human organs and tissues, resulting in distinct symptoms. In this research, electromagnetic propagation and properties in fourteen human organs and tissues were analyzed and investigated based on the organs and tissues’ electromagnetic and mechanical parameters, and chemical composition. Counting the organs and tissues as electromagnetic materials, their permittivity and conductivity, computed by a 4-Cole-Cole …

Using Ai For Management Of Field Emission In Srf Linacs, A. Carpenter, P. Degtiarenko, R. Suleiman, C. Tennant, D. Turner, L. S. Vidyaratne, Khan Iftekharuddin, Md. Monibor Rahman

Electrical & Computer Engineering Faculty Publications

Field emission control, mitigation, and reduction is critical for reliable operation of high gradient superconducting radio-frequency (SRF) accelerators. With the SRF cavities at high gradients, the field emission of electrons from cavity walls can occur and will impact the operational gradient, radiological environment via activated components, and reliability of CEBAF’s two linacs. A new effort has started to minimize field emission in the CEBAF linacs by re-distributing cavity gradients. To measure radiation levels, newly designed neutron and gamma radiation dose rate monitors have been installed in both linacs. Artificial intelligence (AI) techniques will be used to identify cavities with high …

The Energy And Exergy Of Light With Application To Societal Exergy Analysis.Pdf, Matthew K. Heun, Zeke Marshall, Emmanuel Aramendia, Paul E. Brockway

University Faculty Publications and Creative Works

Lighting provides an indispensable energy service, illumination. The field of societal exergy analysis considers light (andmany other energy products) to be enablers of economic growth, and lighting contributes a non-negligible proportion of total useful exergy supplied to modern economies. In societal exergy analysis, the exergetic efficiency of electric lamps is central to determining the exergy contribution of lighting to an economy. Conventionally, societal exergy practitioners estimate the exergetic efficiency of lamps by an energy efficiency, causing confusion and, sometimes, overestimation of exergetic efficiency by a factor as large as 3. In response, we use recent results from the fields of …

A Simple, Realistic Walled Phantom For Intravascular And Intracardiac Applications., Hareem Nisar, John Moore, Roberta Piazza, Efthymios Maneas, Elvis C S Chen, Terry M Peters

Robarts Imaging Publications

PURPOSE: This work aims to develop a simple, anatomically and haptically realistic vascular phantom, compatible with intravascular and intracardiac ultrasound. The low-cost, dual-layered phantom bridges the gap between traditional wall-only and wall-less phantoms by showing both the vessel wall and surrounding tissue in ultrasound imaging. This phantom can better assist clinical tool training, testing of intravascular devices, blood flow studies, and validation of algorithms for intravascular and intracardiac surgical systems.

METHODS: Polyvinyl alcohol cryogel (PVA-c) incorporating a scattering agent was used to obtain vessel and tissue-mimicking materials. Our specific design targeted the inferior vena cava and renal bifurcations which were …

Introducing The Journal Of Nuclear Engineering: An Interdisciplinary Open Access Journal Dedicated To Publishing Research In Nuclear And Radiation Sciences And Applications, Dan Gabriel Cacuci

Faculty Publications

Note: In lieu of an abstract, this is an excerpt from the first page.

In 1938, Strassmann, Hahn and Meitner discovered neutron-induced nuclear fission in uranium, forever changing our world and opening multiple paths to developing nuclear energy, nuclear medicine, instrumentation, space propulsion, environmental monitoring, remediation and nuclear security [...]

Simulation And Verification Of Phase Change Materials For Thermal Energy Storage, Marwan Mosubah Belaed

USF Tampa Graduate Theses and Dissertations

Greenhouse gas (GHG) emissions have a global impact on world economies and the ecosystem. Scientific assessment of GHG emissions is an issue that requires immediate action from key decision-makers and influencers. A comprehensive review of the impact of climate change and its dire consequences on daily life is illustrated in this dissertation. The most common technique to lower GHG emissions in the atmosphere is by switching GHG emission sources to zero-emission sources such as solar energy, wind energy, bioenergy, and geothermal power. Recently, all these technologies have made significant progress in lowering capital operation costs and their cycle efficiencies. This …

Kinetics Of Radiation-Stimulated Processes On The Surface Of Oxide Materials, T. Tusseyev

Eurasian Journal of Physics and Functional Materials

The analysis of the experimental data shows that the processes of gas adsorption and radiation defects accumulation in metal oxides correlate with each other and most likely can be described in terms of equivalent kinetic equations. Given this circumstance, the kinetics of accumulation of radiation defects in oxides of di erent metals was analyzed. The obtained equations were used to analyze: a) the kinetics of accumulation of radiation defects in di erent oxide compounds; b) the data on the destruction of radiationinduced defects in the atmosphere of di erent gases, and on the kinetics of absorption by oxides of oxygen, …

A Quasi-Monte Carlo Solver For Thermal Radiation In Participating Media, Joseph Farmer, Somesh Roy

Mechanical Engineering Faculty Research and Publications

The Monte Carlo (MC) method is the most accurate method for resolving radiative heat transfer in participating media. However, it is also computationally prohibitive in large-scale simulations. To alleviate this, this study proposes a quasi-Monte Carlo (QMC) method for thermal radiation in participating media with a focus on combustion-related problems. The QMC method employs low-discrepancy sequences (LDS) in place of the traditional random numbers. Three different low-discrepancy sequences – Sobol, Halton, and Niederreiter – were examined as part of this work. The developed QMC method was first validated against analytical solutions of radiative heat transfer in several one-dimensional configurations. Then …

Comparison Of Pyrolysis Of Live Wildland Fuels Heated By Radiation Vs. Convection, Mohammad-Saeed Safdari, Elham Amini, David R. Weise, Thomas H. Fletcher

Faculty Publications

During wildland fires, which include both planned (prescribed fire) and unplanned (wildfire) fires, live and dead plants may be subject to both radiative and convective heat transfer mechanisms. In this study, the pyrolysis of 14 live plant species native to the forests of the southern United States was investigated using a flat-flame burner (FFB) apparatus under three heating modes in order to mimic pyrolysis of plants during wildland fires. The heating modes were: (1) radiation-only, where the plants were pyrolyzed under a moderate heating rate of 4 °C s−1 (radiative flux of 50 kW m−2); (2) convection-only, where the FFB …