A Numerical Study In Prediction Of Pressure On High-Speed Planing Craft During Slamming Events,
2018
University of New Orleans
A Numerical Study In Prediction Of Pressure On High-Speed Planing Craft During Slamming Events, Shivank Srivastava
University of New Orleans Theses and Dissertations
This thesis is an attempt to create a computer based tool that can be used academically and later industrially by naval architects in analysis and development of efficient planing hull forms. The work contained here is based on the theory created by Vorus (1996) which falls between empirical asymptotic solutions and intractable non-linear boundary value problem in the time-domain. The computer code developed predicts pressures on the bottom of high-speed planing craft during slamming events. The code is validated with available numerical data as a benchmark case. An aluminum wedge is dropped from various heights resulting in unsteady pressure distributions ...
User's Manual For Tardigrade Risk Assessment,
2018
University of New Orleans
User's Manual For Tardigrade Risk Assessment, Alexis M. Shook
University of New Orleans Theses and Dissertations
This user-guide provides instructions for operating Tardigrade 1.1.3, a cybersecurity software for Nollysoft, LLC. This guide instructs users step-by-step on how to set security controls, risk assessments, and administrative maintenance. Tardigrade 1.1.3 is a Risk Assessment Enterprise that evaluates the risk level of corporations and offers solutions to any security gaps within an organization. Tardigrade 1.1.3 is a role-based software that operates through three modules, Cybersecurity Assessment, Internal Control, and Security Requirement Traceability Matrix.
Remote Monitoring Of Cherry Wetness Using A Leaf Wetness Sensor And A Wireless Sensor Network,
2018
University of New Orleans
Remote Monitoring Of Cherry Wetness Using A Leaf Wetness Sensor And A Wireless Sensor Network, Shyla Clark
University of New Orleans Theses and Dissertations
To get the best prices, sweet cherry growers must supply blemish-free fruit. Unfortunately, mature cherries have a fragile composition, rendering them susceptible to damage from heat, wind, birds, and rain. Rain is particularly devastating, because cherries split when they absorb too much water. Since rainstorms are common in the otherwise arid regions where most cherries are grown, growers must have a system for quickly deploying rain removal methods. The current industry solution relies on human observation and implementation, which is error-prone and costly. This project proposes an automated cherry wetness system using a Decagon Devices leaf wetness sensor (LWS) and ...
Computational Fluid Dynamics Analysis Of Arteriovenous Graft Configurations,
2018
Washington University in St. Louis
Computational Fluid Dynamics Analysis Of Arteriovenous Graft Configurations, Dillon Williams
Engineering and Applied Science Theses & Dissertations
Hemodialysis is a process of external blood filtration that becomes necessary in the event of end stage renal disease. The most common method of the treatment is the creation of an arteriovenous fistula, which is a surgically created connection between a vein and an artery. For patients who are unable to have an arteriovenous fistula, an arteriovenous graft is required. This graft serves to provide an access site for the removal on unfiltered blood and the return of filtered blood. The design and placement of this graft has not yet been optimized based upon mechanical principles. The aim of this ...
An Evaluation Of Proposed And Current Cardiovascular Stent Design Approaches To Aortoiliac Occlusive Disease,
2018
Washington University in St. Louis
An Evaluation Of Proposed And Current Cardiovascular Stent Design Approaches To Aortoiliac Occlusive Disease, Alexander Wirtz
Engineering and Applied Science Theses & Dissertations
Aortoiliac occlusive disease is a subsequent disease of atherosclerosis involving the accumulation of plaque on the lining of the artery wall causing the artery lumen to narrow at the site of the aortic bifurcation. To prevent foreseeable embolization threats or ischemia, revascularization of the aortic bifurcation is commonly treated by arterial stenting. The most common practice of arterial stenting of aortoiliac occlusive disease is using balloon expandable stents. Traditionally, in order to prevent encroachment and/or occlusion of one iliac system by the stenting of the other, two balloon expandable stents are placed in the aortic bifurcation adjacently (kissing) at ...
Modeling Of Swimming Cells From Nano-Scale To Micro-Scale,
2018
Washinton University in St. Louis
Modeling Of Swimming Cells From Nano-Scale To Micro-Scale, Yicheng Zhao
Engineering and Applied Science Theses & Dissertations
Certain human genetic diseases -- primary ciliary dyskinesia, infertility, and hydrocephalus -- are characterized by changes in beat frequency and waveform of cilia and flagella. Chlamydomonas reinhardtii, which is a single-cell green alga about ten micrometers in diameter that swims with two flagella, serves as an excellent biological model because its flagella share the same structure and genetic background as mammalian cilia and flagella. This study uses the finite element method to investigate the behavior of C. reinhardtii swimming from nano-scale to micro-scale. At the device-level, micro-scale modeling indicates that well-designed acoustic microfluidic devices can be used to trap groups of C ...
Inferring Intent From Interaction With Visualization,
2018
Washington University in St. Louis
Inferring Intent From Interaction With Visualization, Ran Wan
Engineering and Applied Science Theses & Dissertations
Today's state-of-the-art analysis tools combine the human visual system and domain knowledge, with the machine's computational power. The human performs the reasoning, deduction, hypothesis generation, and judgment. The entire burden of learning from the data usually rests squarely on the human user's shoulders. This model, while successful in simple scenarios, is neither scalable nor generalizable. In this thesis, we propose a system that integrates advancements from artificial intelligence within a visualization system to detect the user's goals. At a high level, we use hidden unobservable states to represent goals/intentions of users. We automatically infer these ...
Completing Cooperative Task By Utilizing Eeg-Based Brain Computer Interface,
2018
Washington University in St. Louis
Completing Cooperative Task By Utilizing Eeg-Based Brain Computer Interface, Jongwoon Kim
Engineering and Applied Science Theses & Dissertations
We sought to design a cooperative brain computer interface (BCI), wherein multiple users contribute brain activities that are decoded towards a common goal. We used a base design involving collection of electroencephalographic (EEG) brain activity from a low-cost consumer system (the Muse Headband), then classified the ensuing signals into different mental states as either relaxed or focused. The goal of the cooperative BCI was to have two subjects drive a cursor on the screen to some acceptance range given a prescribed path. Each subject was responsible for controlling either the direction or the displacement of the ball. EEG patterns for ...
Exploiting Click-Chemistry And Microfluidics To Map The Neuronal Itinerary Of App Processing And Amyloid-Beta Generation,
2018
Washington University in St. Louis
Exploiting Click-Chemistry And Microfluidics To Map The Neuronal Itinerary Of App Processing And Amyloid-Beta Generation, Namratha Srinivas
Engineering and Applied Science Theses & Dissertations
Alzheimer’s disease (AD) is a chronic neurodegenerative disease and is the sixth leading cause of death in the United States with approximately 5.5 million Americans diagnosed with it. The neuropathological hallmark includes extracellular senile plaques and intraneuronal neurofibrillary tangles. Recent GWAS studies have identified genes associated with AD, and have revealed several classes of genes implicated in disease pathogenesis. In particular, three general pathways associated with an increased risk of AD included: 1) cholesterol metabolism, innate immune system, and the membrane trafficking. Our lab has focused on intracellular trafficking as it relates to the processing of amyloid precursor ...
Optimization Of Gpu-Accelerated Iterative Ct Reconstruction Algorithm For Clinical Use,
2018
Washington University in St. Louis
Optimization Of Gpu-Accelerated Iterative Ct Reconstruction Algorithm For Clinical Use, Tao Ge
Engineering and Applied Science Theses & Dissertations
In order to transition the GPU-accelerated CT reconstruction algorithm to a more clinical environment, a graphical user interface is implemented. Some optimization methods on the implementation are presented. We describe the alternating minimization (AM) algorithm as the updating algorithm, and the branchless distance-driven method for the system forward operator. We introduce a version of the Feldkamp-Davis-Kress algorithm to generate the initial image for our alternating minimization algorithm and compare it to a choice of a constant initial image. For the sake of better rate of convergence, we introduce the ordered-subsets method, find the optimal number of ordered subsets, and discuss ...
Interdigital Capacitance Local Non-Destructive Examination Of Nuclear Power Plant Cable For Aging Management Programs,
2018
Pacific Northwest National Laboratory
Interdigital Capacitance Local Non-Destructive Examination Of Nuclear Power Plant Cable For Aging Management Programs, S. W. Glass, L. S. Fifield, Nicola Bowler, Aishwarya Sriraman, W. C. Palmer
Materials Science and Engineering Publications
This Pacific Northwest National Laboratory milestone report describes progress to date on the investigation of non-destructive test methods focusing on local cable insulation and jacket testing using an interdigital capacitance (IDC) approach. Earlier studies have assessed a number of non-destructive examination (NDE) methods for bulk, distributed, and local cable tests. A typical test strategy is to perform bulk assessments of the cable response using dielectric spectroscopy, Tan , or partial discharge followed by distributed tests like time domain reflectometry or frequency domain reflectometry to identify the most likely defect location followed by a local test that can include visual inspection, indenter ...
High Consequence Scenarios For North Korean Atmospheric Nuclear Tests With Policy Recommendations For The U.S. Government,
2018
James Madison University
High Consequence Scenarios For North Korean Atmospheric Nuclear Tests With Policy Recommendations For The U.S. Government, Thomas S. Popik, Jordan T. Kearns, George H. Baker Iii, Henry F. Cooper, William R. Harris
George H Baker
The government of North Korea has declared high-altitude EMP-capability to be a “strategic goal” and has also threatened an atmospheric test of a hydrogen bomb. Atmospheric nuclear tests have the potential to cripple satellites and the undersea cable networks critical to communication, and navigation necessary for trans-Pacific trade among the U.S., China, and other nations. When a nuclear warhead is detonated at high altitude, a series of electromagnetic pulses radiate downward within the line of sight of the blast. These pulses can disable equipment with miniature electronics and long conductors. Electric grid controls and transmission systems are especially vulnerable ...
Solar Irradiance Forecasting Using Deep Neural Networks,
2018
Missouri University of Science and Technology
Solar Irradiance Forecasting Using Deep Neural Networks, Ahmad Alzahrani, Pourya Shamsi, Cihan H. Dagli, Mehdi Ferdowsi
Pourya Shamsi
Predicting solar irradiance has been an important topic in renewable energy generation. Prediction improves the planning and operation of photovoltaic systems and yields many economic advantages for electric utilities. The irradiance can be predicted using statistical methods such as artificial neural networks (ANN), support vector machines (SVM), or autoregressive moving average (ARMA). However, they either lack accuracy because they cannot capture long-term dependency or cannot be used with big data because of the scalability. This paper presents a method to predict the solar irradiance using deep neural networks. Deep recurrent neural networks (DRNNs) add complexity to the model without specifying ...
Modeling And Simulation Of Microgrid,
2018
Missouri University of Science and Technology
Modeling And Simulation Of Microgrid, Ahmad Alzahrani, Mehdi Ferdowsi, Pourya Shamsi, Cihan H. Dagli
Pourya Shamsi
Complex computer systems and electric power grids share many properties of how they behave and how they are structured. A microgrid is a smaller electric grid that contains several homes, energy storage units, and distributed generators. The main idea behind microgrids is the ability to work even if the main grid is not supplying power. That is, the energy storage unit and distributed generation will supply power in that case, and if there is excess in power production from renewable energy sources, it will go to the energy storage unit. Therefore, the electric grid becomes decentralized in terms of control ...
Chaotic Behavior In High-Gain Interleaved Dc-Dc Converters,
2018
Missouri University of Science and Technology
Chaotic Behavior In High-Gain Interleaved Dc-Dc Converters, Ahmad Alzahrani, Pourya Shamsi, Mehdi Ferdowsi, Cihan H. Dagli
Pourya Shamsi
In this paper, chaotic behavior in high gain dc-dc converters with current mode control is explored. The dc-dc converters exhibit some chaotic behavior because they contain switches. Moreover, in power electronics (circuits with more passive elements), the dynamics become rich in nonlinearity and become difficult to capture with linear analytical models. Therefore, studying modeling approaches and analysis methods is required. Most of the high-gain dc-dc boost converters cannot be controlled with only voltage mode control due to the presence of right half plane zero that narrows down the stability region. Therefore, the need of current mode control is necessary to ...
Singular Perturbation Theory For Dc-Dc Converters And Application To Pfc Converters,
2018
Missouri University of Science and Technology
Singular Perturbation Theory For Dc-Dc Converters And Application To Pfc Converters, Jonathan W. Kimball, Philip T. Krein
Jonathan W. Kimball
Many control schemes for dc-dc converters begin with the assertion that inductor currents are "fast" states and capacitor voltages are "slow" states. This assertion must be true for power factor correction (PFC) converters to allow independent control of current and voltage. In the present work, singular perturbation theory is applied to boost converters to provide rigorous justification of the time scale separation. Krylov-Bogoliubov-Mitropolsky (KBM) averaging is used to include switching ripple effects. A relationship between inductance, capacitance, load resistance, and loss resistances derives from an analysis of an approximate model. Similar results hold for buck and buck-boost converters. An experimental ...
Series-Parallel Approaches And Clamp Methods For Extreme Dynamic Response With Advanced Digital Loads,
2018
Missouri University of Science and Technology
Series-Parallel Approaches And Clamp Methods For Extreme Dynamic Response With Advanced Digital Loads, Philip T. Krein, Jonathan W. Kimball
Jonathan W. Kimball
The series-input parallel-output dc-dc converter combination provides inherent sharing among the converters. With conventional controls, however, this sharing is unstable. Recent literature work proposes complicated feedback loops to correct the problem, at the cost of dynamic performance. This paper shows that a simple sensorless current mode control stabilizes sharing with fast dynamics suitable for advanced digital loads. With this control in place, a "super-matched" current sharing control emerges. Sharing occurs through transients, limited only by the energy limits of the converters. The control approach has considerable promise for high-performance voltage regulator modules. For even faster response, clamping techniques are proposed.
Reducing Common-Mode Voltage In Three-Phase Sine-Triangle Pwm With Interleaved Carriers,
2018
Missouri University of Science and Technology
Reducing Common-Mode Voltage In Three-Phase Sine-Triangle Pwm With Interleaved Carriers, Jonathan W. Kimball, Maciej Jan Zawodniok
Jonathan W. Kimball
Interleaving PWM waveforms is a proven method to reduce ripple in dc-dc converters. The present work explores interleaving for three-phase motor drives. Fourier analysis shows that interleaving the carriers in conventional uniform PWM significantly reduces the common-mode voltage. New DSP hardware supports interleaving directly with changes to just two registers at setup time, so no additional computation time is needed during operation. The common-mode voltage reduction ranges from 36% at full modulation to 67% when idling with zero modulation. Third harmonic injection slightly reduces the advantage (to 26% at full modulation). However, the maximum RMS common-mode voltage is still less ...
Predicting Solar Irradiance Using Time Series Neural Networks,
2018
Missouri University of Science and Technology
Predicting Solar Irradiance Using Time Series Neural Networks, Ahmad Alzahrani, Jonathan W. Kimball, Cihan H. Dagli
Jonathan W. Kimball
Increasing the accuracy of prediction improves the performance of photovoltaic systems and alleviates the effects of intermittence on the systems stability. A Nonlinear Autoregressive Network with Exogenous Inputs (NARX) approach was applied to the Vichy-Rolla National Airport's photovoltaic station. The proposed model uses several inputs (e.g. time, day of the year, sky cover, pressure, and wind speed) to predict hourly solar irradiance. Data obtained from the National Solar Radiation Database (NSRDB) was used to conduct simulation experiments. These simulations validate the use of the proposed model for short-term predictions. Results show that the NARX neural network notably outperformed ...
Modern Laboratory-Based Education For Power Electronics And Electric Machines,
2018
Missouri University of Science and Technology
Modern Laboratory-Based Education For Power Electronics And Electric Machines, Robert S. Balog, Zakdy Sorchini, Jonathan W. Kimball, Patrick L. Chapman, Philip T. Krein
Jonathan W. Kimball
The study of modern energy conversion draws upon a broad range of knowledge and often requires a fair amount of experience. This suggests that laboratory instruction should be an integral component of a power electronics and electric machines curriculum. However, before a single watt can be processed in a realistic way, the student must understand not only the operation of conversion systems but also more advanced concepts such as control theory, speed and position sensing, switching signal generation, gate drive isolation, circuit layout, and other critical issues. Our approach is to use a blue-box module where these details are pre-built ...
