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Full-Text Articles in Engineering

Nanosecond Pulsed Platelet-Rich Plasma (Nsprp) Improves Mechanical And Electrial Cardiac Function Following Myocardial Reperfusion Injury, Barbara Y. Hargrave, Frency Varghese, Nektarios Barabutis, John Catravas, Christian Zemlin Jan 2016

Nanosecond Pulsed Platelet-Rich Plasma (Nsprp) Improves Mechanical And Electrial Cardiac Function Following Myocardial Reperfusion Injury, Barbara Y. Hargrave, Frency Varghese, Nektarios Barabutis, John Catravas, Christian Zemlin

School of Medical Diagnostics & Translational Sciences Publications

Ischemia and reperfusion (I/R) of the heart is associated with biochemical and ionic changes that result in cardiac contractile and electrical dysfunction. In rabbits, platelet-rich plasma activated using nanosecond pulsed electric fields (nsPRP) has been shown to improve left ventricular pumping. Here, we demonstrate that nsPRP causes a similar improvement in mouse left ventricular function. We also show that nsPRP injection recovers electrical activity even before reperfusion begins. To uncover the mechanism of nsPRP action, we studied whether the enhanced left ventricular function in nsPRP rabbit and mouse hearts was associated with increased expression of heat-shock proteins and altered mitochondrial …


Modeling Early Stage Bone Regeneration With Biomimetic Electrospun Fibrinogen Nanofibers And Adipose-Derived Mesenchymal Stem Cells, Michael P. Francis, Yas M. Moghaddam-White, Patrick C. Sachs, Matthew J. Beckman, Stephen M. Chen, Gary L. Bowlin, Lynne W. Elmore, Shawn E. Holt Jan 2016

Modeling Early Stage Bone Regeneration With Biomimetic Electrospun Fibrinogen Nanofibers And Adipose-Derived Mesenchymal Stem Cells, Michael P. Francis, Yas M. Moghaddam-White, Patrick C. Sachs, Matthew J. Beckman, Stephen M. Chen, Gary L. Bowlin, Lynne W. Elmore, Shawn E. Holt

School of Medical Diagnostics & Translational Sciences Publications

The key events of the earliest stages of bone regeneration have been described in vivo although not yet modeled in an in vitro environment, where mechanistic cell-matrix-growth factor interactions can be more effectively studied. Here, we explore an early-stage bone regeneration model where the ability of electrospun fibrinogen (Fg) nanofibers to regulate osteoblastogenesis between distinct mesenchymal stem cells populations is assessed. Electrospun scaffolds of Fg, polydioxanone (PDO), and a Fg:PDO blend were seeded with adipose-derived mesenchymal stem cells (ASCs) and grown for 7-21 days in osteogenic differentiation media or control growth media. Scaffolds were analyzed weekly for histologic and molecular …


Accessible Bioprinting: Adaptation Of A Low-Cost 3d-Printer For Precise Cell Placement And Stem Cell Differentiation, John A. Reid, Peter A. Mollica, Garett D. Johnson, Roy C. Ogle, Robert D. Bruno, Patrick C. Sachs Jan 2016

Accessible Bioprinting: Adaptation Of A Low-Cost 3d-Printer For Precise Cell Placement And Stem Cell Differentiation, John A. Reid, Peter A. Mollica, Garett D. Johnson, Roy C. Ogle, Robert D. Bruno, Patrick C. Sachs

School of Medical Diagnostics & Translational Sciences Publications

The precision and repeatability offered by computer-aided design and computer-numerically controlled techniques in biofabrication processes is quickly becoming an industry standard. However, many hurdles still exist before these techniques can be used in research laboratories for cellular and molecular biology applications. Extrusion-based bioprinting systems have been characterized by high development costs, injector clogging, difficulty achieving small cell number deposits, decreased cell viability, and altered cell function post-printing. To circumvent the high-price barrier to entry of conventional bioprinters, we designed and 3D printed components for the adaptation of an inexpensive 'off-the-shelf' commercially available 3D printer. We also demonstrate via goal based …


Categorizing Fetal Heart Rate Variability With And Without Visual Aids, Amanda J. Ashdown, Mark W. Scerbo, Lee A. Belfore Ii, Stephen S. Davis, Alfred Z. Abuhamad Jan 2016

Categorizing Fetal Heart Rate Variability With And Without Visual Aids, Amanda J. Ashdown, Mark W. Scerbo, Lee A. Belfore Ii, Stephen S. Davis, Alfred Z. Abuhamad

Psychology Faculty Publications

Objective This study examined the ability of clinicians to correctly categorize images of fetal heart rate (FHR) variability with and without the use of exemplars.

Study Design A sample of 33 labor and delivery clinicians inspected static FHR images and categorized them into one of four categories defined by the National Institute of Child Health and Human Development (NICHD) based on the amount of variability within absent, minimal, moderate, or marked ranges. Participants took part in three conditions: two in which they used exemplars representing FHR variability near the center or near the boundaries of each range, and a third …


The Influence Of A Crosshair Visual Aid On Observer Detection Of Simulated Fetal Heart Rate Signals, Rebecca A. Kennedy, Mark W. Scerbo, Brittany L. Anderson-Montoya, Lee A. Belfore Ii, Alfred Z. Abuhamad, Stephen S. Davis Jan 2016

The Influence Of A Crosshair Visual Aid On Observer Detection Of Simulated Fetal Heart Rate Signals, Rebecca A. Kennedy, Mark W. Scerbo, Brittany L. Anderson-Montoya, Lee A. Belfore Ii, Alfred Z. Abuhamad, Stephen S. Davis

Psychology Faculty Publications

Objective To determine whether a visual aid overlaid on fetal heart rate (FHR) tracings increases detection of critical signals relative to images with no visual aid.

Study Design In an experimental study, 21 undergraduate students viewed 240 images of simulated FHR tracings twice, once with the visual aids and once without aids. Performance was examined for images containing three different types of FHR signals (early deceleration, late deceleration, and acceleration) and four different FHR signal-to-noise ratios corresponding to FHR variability types (absent, minimal, moderate, and marked) identified by the National Institute of Child Health and Human Development (2008). Performance was …


Age-Related Differences In Vehicle Control And Eye Movement Patterns At Intersections: Older And Middle-Aged Drivers, Yusuke Yamani, William J. Horrey, Yulan Liang, Donald L. Fisher Jan 2016

Age-Related Differences In Vehicle Control And Eye Movement Patterns At Intersections: Older And Middle-Aged Drivers, Yusuke Yamani, William J. Horrey, Yulan Liang, Donald L. Fisher

Psychology Faculty Publications

Older drivers are at increased risk of intersection crashes. Previous work found that older drivers execute less frequent glances for detecting potential threats at intersections than middle-aged drivers. Yet, earlier work has also shown that an active training program doubled the frequency of these glances among older drivers, suggesting that these effects are not necessarily due to age-related functional declines. In light of findings, the current study sought to explore the ability of older drivers to coordinate their head and eye movements while simultaneously steering the vehicle as well as their glance behavior at intersections. In a driving simulator, older …


An Efficient Method For Optimizing Segmentation Parameters, Jacob D' Avy, Wei-Wen Hsu, Chung-Hao Chen, Andreas F. Koschan, Mongi Abidi Jan 2016

An Efficient Method For Optimizing Segmentation Parameters, Jacob D' Avy, Wei-Wen Hsu, Chung-Hao Chen, Andreas F. Koschan, Mongi Abidi

Electrical & Computer Engineering Faculty Publications

Segmenting an image into meaningful regions is an important step in many computer vision applications such as facial recognition, target tracking and medical image analysis. Because image segmentation is an ill-posed problem, parameters are needed to constrain the solution to one that is suitable for a given application. For a user, setting parameter values is often unintuitive. We present a method for automating segmentation parameter selection using an efficient search method to optimize a segmentation objective function. Efficiency is improved by utilizing prior knowledge about the relationship between a segmentation parameter and the objective function terms. An adaptive sampling of …


Java Based Visualization And Animation For Teaching The Dijkstra Shortest Path Algorithm In Transportation Networks, Ivan Makohon, Duc T. Nguyen, Masha Sosonkina, Yuzhong Shen, Manwo Ng Jan 2016

Java Based Visualization And Animation For Teaching The Dijkstra Shortest Path Algorithm In Transportation Networks, Ivan Makohon, Duc T. Nguyen, Masha Sosonkina, Yuzhong Shen, Manwo Ng

Civil & Environmental Engineering Faculty Publications

Shortest path (SP) algorithms, such as the popular Dijkstra algorithm has been considered as the "basic building blocks" for many advanced transportation network models. Dijkstra algorithm will find the shortest time (ST) and the corresponding SP to travel from a source node to a destination node. Applications of SP algorithms include real-time GPS and the Frank-Wolfe network equilibrium.

For transportation engineering students, the Dijkstra algorithm is not easily understood. This paper discusses the design and development of a software that will help the students to fully understand the key components involved in the Dijkstra SP algorithm. The software presents an …


Expanding The Class Of Globally Convergent Fliess Operators, Irina M. Winter-Arboleda, W. Steven Gray, Luis A. Duffaut Espinosa Jan 2016

Expanding The Class Of Globally Convergent Fliess Operators, Irina M. Winter-Arboleda, W. Steven Gray, Luis A. Duffaut Espinosa

Electrical & Computer Engineering Faculty Publications

A common representation of an input-output system in nonlinear control theory is the Chen-Fliess functional series or fliess operator. Such a functional series is said to be globally convergent when there is no a priori upper bound on both the L₁-norm of an admissible input and the length of time over which the corresponding output is well defined. It is known that every Fliess operator having a generating series with Gevrey order 0 ≤ s < 1 is globally convergent. In this paper it is shown that there exists a subset of series with Gevrey order s = 1 which also exhibit global convergence. In particular, the example of Ferfera, which arises in the context of system interconnections, is shown to be one such example.


Nonrecursively Interconnected Fliess Operators Preserve Global Convergence: An Expanded View, Irina M. Winter-Arboleda, Luis A. Duffaut Espinosa, W. Steven Gray Jan 2016

Nonrecursively Interconnected Fliess Operators Preserve Global Convergence: An Expanded View, Irina M. Winter-Arboleda, Luis A. Duffaut Espinosa, W. Steven Gray

Electrical & Computer Engineering Faculty Publications

A common representation of an input-output system in nonlinear control theory is the Chen-Fliess functional series or Fliess operator. Such a functional series is said to be globally convergent when there is a no a priori upper bound on both the L₁-norm of an admissible input and the length of time over which the corresponding output is well defined. Recent developments have expanded the class of globally convergent Fliess operators. The goal of this paper is to show that the global convergence property is preserved for nonrecursive inter-connections (i.e., the parallel, product and cascade connections) involving this largest known class …


An Improved Smote Algorithm Based On Genetic Algorithm For Imbalanced Data Collection, Qiong Gu, Xian-Ming Wang, Zhao Wu, Bing Ning, Chun-Sheng Xin Jan 2016

An Improved Smote Algorithm Based On Genetic Algorithm For Imbalanced Data Collection, Qiong Gu, Xian-Ming Wang, Zhao Wu, Bing Ning, Chun-Sheng Xin

Electrical & Computer Engineering Faculty Publications

Classification of imbalanced data has been recognized as a crucial problem in machine learning and data mining. In an imbalanced dataset, minority class instances are likely to be misclassified. When the synthetic minority over-sampling technique (SMOTE) is applied in imbalanced dataset classification, the same sampling rate is set for all samples of the minority class in the process of synthesizing new samples, this scenario involves blindness. To overcome this problem, an improved SMOTE algorithm based on genetic algorithm (GA), namely, GASMOTE was proposed. First, GASMOTE set different sampling rates for different minority class samples. A combination of the sampling rates …


Ultra-Compact Raman Spectrometer For Planetary Explorations, Derek Davis, James Hornef, John Lucas, Hani Elsayed-Ali, M. Nural Abedin Jan 2016

Ultra-Compact Raman Spectrometer For Planetary Explorations, Derek Davis, James Hornef, John Lucas, Hani Elsayed-Ali, M. Nural Abedin

Electrical & Computer Engineering Faculty Publications

To develop a compact Raman spectroscopy system with features that will make it suitable for future space missions which require surface landing. Specifically, this system will be appropriate for any mission in which planetary surface samples need to be measured and analyzed.


Developing A Student Learning Strategy To Bridge Virtual Learning And Hands-On Activity, Gon Namkoong, Hargsoon Yoon, Yonghee Suh Jan 2016

Developing A Student Learning Strategy To Bridge Virtual Learning And Hands-On Activity, Gon Namkoong, Hargsoon Yoon, Yonghee Suh

Electrical & Computer Engineering Faculty Publications

This paper addresses the effectiveness of combined virtual and physical hands-on activities in students’ learning which was infused in the capstone senior design project. Senior design projects are open-ended and are similar to the research that scientists perform toward a more comprehensive understanding of nature or new scientific knowledge. As a reinforced learning methodology to greatly assist students’ reasoning and problem-solving skills, virtual learning was first integrated at the planning stage of their projects. This approach is in contrast with the typical senior design courses where only limited resources are available for planning experiments. Using virtual learning, students are able …


Rapid And Accurate C-V Measurements, Ji-Hong Kim, Pragya R. Shrestha, Jason P. Campbell, Jason T. Ryan, David Nminibapiel, Joseph J. Kopanski Jan 2016

Rapid And Accurate C-V Measurements, Ji-Hong Kim, Pragya R. Shrestha, Jason P. Campbell, Jason T. Ryan, David Nminibapiel, Joseph J. Kopanski

Electrical & Computer Engineering Faculty Publications

We report a new technique for the rapid measurement of full capacitance-voltage (C-V) characteristic curves. The displacement current from a 100-MHz applied sine wave, which swings from accumulation to strong inversion, is digitized directly using an oscilloscope from the MOS capacitor under test. A C-V curve can be constructed directly from this data but is severely distorted due to nonideal behavior of real measurement systems. The key advance of this paper is to extract the system response function using the same measurement setup and a known MOS capacitor. The system response correction to the measured C-V curve of the unknown …


Java Computer Animation For Effective Learning Of The Cholesky Algorithm With Transportation Engineering Applications, Ivan Makohon, Duc T. Nguyen, Mecit Cetin Jan 2016

Java Computer Animation For Effective Learning Of The Cholesky Algorithm With Transportation Engineering Applications, Ivan Makohon, Duc T. Nguyen, Mecit Cetin

Civil & Environmental Engineering Faculty Publications

In this paper, the well-known Cholesky Algorithm (for solving simultaneous linear equations, or SLE) is re-visited, with the ultimate goal of developing a simple, user-friendly, attractive, and useful Java Visualization and Animation Graphical User Inter-face (GUI) software as an additional teaching tool for students to learn the Cholesky factorization in a step-by-step fashion with computer voice and animation. A demo video of the Cholesky Decomposition (or factorization) animation and result can be viewed online from the website: http://www.lions.odu.edu/~imako001/cholesky/demo/index.html. The software tool developed from this work can be used for both students and their instructors not only to master this technical …


Flexc: Protein Flexibility Prediction Using Context-Based Statistics, Predicted Structural Features, And Sequence Information, Ashraf Yaseen, Mais Nijim, Brandon Williams, Lei Qian, Min Li, Jianxin Wang, Yaohang Li Jan 2016

Flexc: Protein Flexibility Prediction Using Context-Based Statistics, Predicted Structural Features, And Sequence Information, Ashraf Yaseen, Mais Nijim, Brandon Williams, Lei Qian, Min Li, Jianxin Wang, Yaohang Li

Computer Science Faculty Publications

The fluctuation of atoms around their average positions in protein structures provides important information regarding protein dynamics. This flexibility of protein structures is associated with various biological processes. Predicting flexibility of residues from protein sequences is significant for analyzing the dynamic properties of proteins which will be helpful in predicting their functions.


Leveraging Heritrix And The Wayback Machine On A Corporate Intranet: A Case Study On Improving Corporate Archives, Justin F. Brunelle, Krista Ferrante, Eliot Wilczek, Michele C. Weigle, Michael L. Nelson Jan 2016

Leveraging Heritrix And The Wayback Machine On A Corporate Intranet: A Case Study On Improving Corporate Archives, Justin F. Brunelle, Krista Ferrante, Eliot Wilczek, Michele C. Weigle, Michael L. Nelson

Computer Science Faculty Publications

In this work, we present a case study in which we investigate using open-source, web-scale web archiving tools (i.e., Heritrix and the Wayback Machine installed on the MITRE Intranet) to automatically archive a corporate Intranet. We use this case study to outline the challenges of Intranet web archiving, identify situations in which the open source tools are not well suited for the needs of the corporate archivists, and make recommendations for future corporate archivists wishing to use such tools. We performed a crawl of 143,268 URIs (125 GB and 25 hours) to demonstrate that the crawlers are easy to set …


Analyses Of 476 Mhz And 952 Mhz Crab Cavities For Jlab Electron Ion Collider, Hyekyoung Park, A. Castilla, J. R. Delayen, S. U. De Silva, V. Morozov Jan 2016

Analyses Of 476 Mhz And 952 Mhz Crab Cavities For Jlab Electron Ion Collider, Hyekyoung Park, A. Castilla, J. R. Delayen, S. U. De Silva, V. Morozov

Physics Faculty Publications

Center for Accelerator Science at ODU has designed, fabricated and successfully tested a crab cavity for MEIC at Jefferson Lab*. This proof of principle cavity was based on the earlier MEIC design which used 748.5 MHz RF system. The updated MEIC design** utilizes the components from PEP-II. It results in the change on the bunch repetition rate of stored beam to 476.3 MHz. The ion ring collider will eventually require 952.6 MHz crab cavity. This paper will present the analyses of crab cavities of both 476 MHz and 952 MHz options. It compares advantages and disadvantages of the options which …


College Students' Perceptions Of Sustainability: A Regional Survey, Michael Myung Jeong, Younghan Jung, Dan Daehyun Koo Dec 2015

College Students' Perceptions Of Sustainability: A Regional Survey, Michael Myung Jeong, Younghan Jung, Dan Daehyun Koo

Engineering Technology Faculty Publications

Understanding college students’ perception of sustainability is paramount as today’s students will soon be driving our economy and taking on the responsibility of maintaining a sustainable society. This study conducted a survey of college students attending two regional universities in the United States to capture their current experience levels, expectations, and perceptions with regard to various aspects of sustainability utilizing a questionnaire consisting of structured questions about sustainability knowledge/familiarity levels, green product purchase behavior, attitude-behavior relationship, and sustainability education. The results reveal useful insights into the students’ views on these topics and the demographic data collected were further analyzed to …


Energy-Efficient Computational Chemistry: Comparison Of X86 And Arm Systems, Kristopher Keipert, Gaurav Mitra, Vaibhav Sunriyal, Sarom S. Leang, Masha Sosonkina, Alistair P. Rendell, Mark S. Gordon Nov 2015

Energy-Efficient Computational Chemistry: Comparison Of X86 And Arm Systems, Kristopher Keipert, Gaurav Mitra, Vaibhav Sunriyal, Sarom S. Leang, Masha Sosonkina, Alistair P. Rendell, Mark S. Gordon

Computational Modeling & Simulation Engineering Faculty Publications

The computational efficiency and energy-to-solution of several applications using the GAMESS quantum chemistry suite of codes is evaluated for 32-bit and 64-bit ARM-based computers, and compared to an x86 machine. The x86 system completes all benchmark computations more quickly than either ARM system and is the best choice to minimize time to solution. The ARM64 and ARM32 computational performances are similar to each other for Hartree-Fock and density functional theory energy calculations. However, for memory-intensive second-order perturbation theory energy and gradient computations the lower ARM32 read/write memory bandwidth results in computation times as much as 86% longer than on the …


Corps Efforts On Sea Level Rise In Hampton Roads, Greg Steele Oct 2015

Corps Efforts On Sea Level Rise In Hampton Roads, Greg Steele

October 30, 2015: Beyond Toolkits: Adaptation Strategies and Lessons

No abstract provided.


Panel Presentation: Regional Working Group, Regional Working Group Oct 2015

Panel Presentation: Regional Working Group, Regional Working Group

October 30, 2015: Beyond Toolkits: Adaptation Strategies and Lessons

No abstract provided.


Panel Presentation: Norfolk: Thriving With Water, Norfolk Working Group Oct 2015

Panel Presentation: Norfolk: Thriving With Water, Norfolk Working Group

October 30, 2015: Beyond Toolkits: Adaptation Strategies and Lessons

No abstract provided.


Designing A Resilient Building In The Coastal Zone, Don Kranbuehl, David Pryor Oct 2015

Designing A Resilient Building In The Coastal Zone, Don Kranbuehl, David Pryor

October 30, 2015: Beyond Toolkits: Adaptation Strategies and Lessons

No abstract provided.


Multiple Point Constraint (Mpc)-Based Variable Node Super-Element, Mohamad Eftekharjoo Oct 2015

Multiple Point Constraint (Mpc)-Based Variable Node Super-Element, Mohamad Eftekharjoo

Mechanical & Aerospace Engineering Theses & Dissertations

The multiple point constraint (MPC)-based variable node element is introduced in this study to handle mismatched meshes between sub-domains in finite element analysis. The MPC-variable node element is a collection of a group of elements. The compatibility condition along the interface boundary is imposed along the edge of these elements through Lagrange multipliers. The Elimination method is then used to remove the effects of the dependent nodes in these elements to produce a single MPC-based variable node element. The derived variable node elements are applied to solve two plane strain problems in order to validate the accuracy of the proposed …


Using Eye And Head Movements As A Control Mechanism For Tele-Operating A Ground-Based Robot And Its Payload, Kathryn C. Hicks Oct 2015

Using Eye And Head Movements As A Control Mechanism For Tele-Operating A Ground-Based Robot And Its Payload, Kathryn C. Hicks

Computational Modeling & Simulation Engineering Theses & Dissertations

To date, eye and head tracking has been used to indicate users' attention patterns while performing a task or as an aid for disabled persons, to allow hands-free interaction with a computer. The increasing accuracy and the reduced cost of eye- and head-tracking equipment make utilizing this technology feasible for explicit control tasks, especially in cases where there is confluence between the visual task and control.

The goal of this research was to investigate the use of eye-tracking as a more natural interface for the control of a camera-equipped, remotely operated robot in tasks that require the operator to simultaneously …


Synthesis, Characterisation, Electrochemical, And Spectroscopic Studies Of Cobaloximes: Unique Clues Of Cobalt(I) Species In Various Solvents, Michael John Celestine Oct 2015

Synthesis, Characterisation, Electrochemical, And Spectroscopic Studies Of Cobaloximes: Unique Clues Of Cobalt(I) Species In Various Solvents, Michael John Celestine

Chemistry & Biochemistry Theses & Dissertations

With the dwindling amount of fossil fuels in the world’s reserve is said to run out in the future. The use of alternative fuels such as hydrogen can be produced from renewable sources. One source is the use of first row transition metal complexes that can harness the power of the sun to reduce protons to hydrogen. In this thesis we investigated a well-known hydrogen evolution catalyst in a quest to understand the behavior of different oxidation states that occur during the catalytic cycle.

In an attempt to synthesize a binuclear ruthenium(II) complex, [{Ru(phen)2}2{µmes(1,4-phO-Izphen)3}](PF6)4, as a possible photosensitizer for the …


Techno-Economic Analysis Of Protein Concentrate Produced By Flash Hydrolysis Of Microalgae, Alexander Nana Yaw Asiedu Oct 2015

Techno-Economic Analysis Of Protein Concentrate Produced By Flash Hydrolysis Of Microalgae, Alexander Nana Yaw Asiedu

Civil & Environmental Engineering Theses & Dissertations

Process simulation and techno-economic analysis of 95wt.% protein concentrate from microalgae has been performed using SuperPro Designer v. 9.0. This work, first of its kind, is focused on the economic analysis of protein concentrate that includes processes such as microalgae cultivation, harvesting, protein extraction and drying steps. A baseline capacity of 160 MT/day protein concentrate production on commercial basis has been analyzed. This throughput requires 336 MT/day dry algae (54 wt.% protein). The amount of carbon dioxide required to grow this quantum of algae is estimated to be 648 MT/day, which is produced from an in situ 21 MW power …


Examining The Relationship Between Leadership Decision Making Styles And Personality Type Within The Department Of Defense, Antoine Lamont Prince Sr. Oct 2015

Examining The Relationship Between Leadership Decision Making Styles And Personality Type Within The Department Of Defense, Antoine Lamont Prince Sr.

Engineering Management & Systems Engineering Theses & Dissertations

Leadership is perhaps the single most important function within the Department of Defense. While the old cliché “everyone is a leader regardless of position” may hold moral meaning, personnel in leadership positions are key. Under the umbrella of leadership is decision making. What leadership is to an organization, decision making is to leadership. Yet, despite this knowledge, unsound decisions are readily conducted. There are various theories as to why this holds true, one of which is personality type. Research however, shows that there is a limited amount of relevant knowledge to determine if there is in fact a …


Numerical Studies And Optimization Of Magnetron With Diffraction Output (Mdo) Using Particle-In-Cell Simulations, Alireza Majzoobi Oct 2015

Numerical Studies And Optimization Of Magnetron With Diffraction Output (Mdo) Using Particle-In-Cell Simulations, Alireza Majzoobi

Electrical & Computer Engineering Theses & Dissertations

The first magnetron as a vacuum-tube device, capable of generating microwaves, was invented in 1913. This thesis research focuses on numerical simulation-based analysis of magnetron performance. The particle-in-cell (PIC) based MAGIC software tool has been utilized to study the A6 and the Rising-Sun magnetron structures, and to obtain the optimized geometry for optimizing the device performance. The A6 magnetron is the more traditional structure and has been studied more often. The Rising-Sun geometry, consists of two alternating groups of short and long vanes in angular orientation, and was created to achieve mode stability.

The effect of endcaps, changes in lengths …