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Rotordynamic Analysis Of Theoretical Models And Experimental Systems, Cameron R. Naugle, Cameron Rex Naugle 2018 California Polytechnic State University - San Luis Obispo

Rotordynamic Analysis Of Theoretical Models And Experimental Systems, Cameron R. Naugle, Cameron Rex Naugle

Master's Theses and Project Reports

This thesis is intended to provide fundamental information for the construction and

analysis of rotordynamic theoretical models, and their comparison the experimental

systems. Finite Element Method (FEM) is used to construct models using Timoshenko

beam elements with viscous and hysteretic internal damping. Eigenvalues

and eigenvectors of state space equations are used to perform stability analysis, produce

critical speed maps, and visualize mode shapes. Frequency domain analysis

of theoretical models is used to provide Bode diagrams and in experimental data

full spectrum cascade plots. Experimental and theoretical model analyses are used

to optimize the control algorithm for an Active Magnetic Bearing ...


Applying Neural Networks For Tire Pressure Monitoring Systems, Alex Kost 2018 California Polytechnic State University, San Luis Obispo

Applying Neural Networks For Tire Pressure Monitoring Systems, Alex Kost

Master's Theses and Project Reports

A proof-of-concept indirect tire-pressure monitoring system is developed using neural net- works to identify the tire pressure of a vehicle tire. A quarter-car model was developed with Matlab and Simulink to generate simulated accelerometer output data. Simulation data are used to train and evaluate a recurrent neural network with long short-term memory blocks (RNN-LSTM) and a convolutional neural network (CNN) developed in Python with Tensorflow. Bayesian Optimization via SigOpt was used to optimize training and model parameters. The predictive accuracy and training speed of the two models with various parameters are compared. Finally, future work and improvements are discussed.


Turbulence Closure Models For Computational Fluid Dynamics, Paul A. Durbin 2018 Iowa State University

Turbulence Closure Models For Computational Fluid Dynamics, Paul A. Durbin

Aerospace Engineering Publications

The formulation of analytical turbulence closure models for use in computational fluid mechanics is described. The subject of this chapter is the types of models that are used to predict the statistically averaged flow field – commonly known as Reynolds‐averaged Navier–Stokes equations (RANS) modeling. A variety of models are reviewed: these include two‐equation, eddy viscosity transport, and second moment closures. How they are formulated is not the main theme; it enters the discussion but the models are presented largely at an operational level. Several issues related to numerical implementation are discussed. Relative merits of the various formulations are ...


Image-Based Modeling Of Flow Through Porous Media: Development Of Multiscale Techniques For The Pore Level, Timothy Wayne Thibodeaux 2018 Louisiana State University and Agricultural and Mechanical College

Image-Based Modeling Of Flow Through Porous Media: Development Of Multiscale Techniques For The Pore Level, Timothy Wayne Thibodeaux

LSU Doctoral Dissertations

Increasingly, imaging technology allows porous media problems to be modeled at microscopic and sub-microscopic levels with finer resolution. However, the physical domain size required to be representative of the media prohibits comprehensive micro-scale simulation. A hybrid or multiscale approach is necessary to overcome this challenge. In this work, a technique was developed for determining the characteristic scales of porous materials, and a multiscale modeling methodology was developed to better understand the interaction/dependence of phenomena occurring at different microscopic scales. The multiscale method couples microscopic simulations at the pore and sub-pore scales. Network modeling is a common pore-scale technique which ...


Master Of Science In Information Technology, Nova Southeastern University 2018 Nova Southeastern University

Master Of Science In Information Technology, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.


Improving Table Scans For Trie Indexed Databases, Ethan Toney 2018 University of Kentucky

Improving Table Scans For Trie Indexed Databases, Ethan Toney

Theses and Dissertations--Computer Science

We consider a class of problems characterized by the need for a string based identifier that reflect the ontology of the application domain. We present rules for string-based identifier schemas that facilitate fast filtering in databases used for this class of problems. We provide runtime analysis of our schema and experimentally compare it with another solution. We also discuss performance in our solution to a game engine. The string-based identifier schema can be used in addition scenarios such as cloud computing. An identifier schema adds metadata about an element. So the solution hinges on additional memory but as long as ...


Pressure Measurements Inside Multiple Cavities Of A Torque Converter And Cfd Correlation, Edward De Jesus Rivera 2018 Michigan Technological University

Pressure Measurements Inside Multiple Cavities Of A Torque Converter And Cfd Correlation, Edward De Jesus Rivera

Dissertations, Master's Theses and Master's Reports

A torque converter was instrumented with 29 pressure transducers. The pressure transducers were located in multiple cavities. The instrumented cavities included, four transducers mounted on the impeller shell, on the channel between blades. Six transducers mounted on the pressure and suction sides on the middle streamline of a turbine blade. Another seven transducers mounted on the pressure and suction sides of the core, middle and shell streamlines of a stator blade. Seven transducers mounted on the torque converter clutch cavity. Finally, five on the cavity between the pressure plate and the turbine shell. The torque converter was part of a ...


Tracking Pose Using Common Mobile Phone Sensors, Andrew Lee Carlson 2018 Bard College

Tracking Pose Using Common Mobile Phone Sensors, Andrew Lee Carlson

Senior Projects Spring 2018

The original goal of this project was to develop an accurate ”tape measure” application for Android based mobile phones. The main challenge for such applications is to construct one method that ensures a given Android device can, with accuracy and precision, estimate its own position and movement.

The author developed an application in the Unity 3D game environment in order to understand the challenges of such estimation. This required translation of accelerometer and gyroscope data to the Unity platform. Efficient computation required easy translation from right-handed coordinates to left-handed coordinates. Moreover, it is necessary to design and implement calibration procedures ...


Dynamics Of Crowded And Active Biological Systems, Michael W. Stefferson 2018 University of Colorado at Boulder

Dynamics Of Crowded And Active Biological Systems, Michael W. Stefferson

Physics Graduate Theses & Dissertations

Interactions between particles and their environment can alter the dynamics of biological systems. In crowded media like the cell, interactions with obstacles can introduce anomalous subdiffusion. Active matter systems, e.g., bacterial swarms, are nonequilibrium fluids where interparticle interactions and activity cause collective motion and dynamical phases. In this thesis, I discuss my advances in the fields of crowded media and active matter. For crowded media, I studied the effects of soft obstacles and bound mobility on tracer diffusion using a lattice Monte Carlo model. I characterized how bound motion can minimize the effects of hindered anomalous diffusion and obstacle ...


Beyond The Standard Model With Composite Particles: A Lattice Study Based On Su(4), William I. Jay 2018 University of Colorado at Boulder

Beyond The Standard Model With Composite Particles: A Lattice Study Based On Su(4), William I. Jay

Physics Graduate Theses & Dissertations

This thesis is about numerical simulations of a strongly coupled quantum field theory. The quantum field theory is a gauge theory based on the group SU(4) and contains fermionic matter charged under two different representations of the gauge group. The motivation for studying this theory is twofold. First, this theory is closely related to a theory of physics beyond the Standard Model which was recently proposed in the literature. In this model, the Higgs boson is a composite particle, and the top quark is a partially composite particle. Second, theories of this sort represent a new direction in the ...


Numerical Coupling Of Fracture And Fluid Pressure Using A Phase-Field Model With Applications In Geomechanics, David B. Culp 2018 University of Colorado at Boulder

Numerical Coupling Of Fracture And Fluid Pressure Using A Phase-Field Model With Applications In Geomechanics, David B. Culp

Civil Engineering Graduate Theses & Dissertations

The application of fracture mechanics is an increasingly important topic in fields including geophysics, geomechanics, materials engineering, structural mechanics and engineering design. The initiation and evolution of fractures in porous media often gives rise to discontinuous fields within computational problems. We compute the crack's aperture, or crack opening, by making use of the gradient of the phase-field in the damaged area. This is useful for determining the material's fluid-mechanical properties, such as the estimation of Poiseuille-type flow that occurs within a sufficiently damaged medium. Using this approach, it can be shown that the evolution of such fractures in ...


Modeling The Impacts Of Sea Level Rise On Storm Surge Inundation In Flood-Prone Urban Areas Of Hampton Roads, Virginia, Luca Castrucci, Navid Tahvildari 2018 Old Dominion University

Modeling The Impacts Of Sea Level Rise On Storm Surge Inundation In Flood-Prone Urban Areas Of Hampton Roads, Virginia, Luca Castrucci, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

Hampton Roads is a populated area in the United States Mid-Atlantic region that is highly affected by sea level rise (SLR). The transportation infrastructure in the region is increasingly disrupted by storm surge and even minor flooding events. The purpose of this study is to improve our understanding of SLR impacts on storm surge flooding in the region. We develop a hydrodynamic model to study the vulnerability of several critical flood-prone neighborhoods to storm surge flooding under several SLR projections. The hydrodynamic model is validated for tide prediction, and its performance in storm surge simulation is validated with the water ...


Quantitative Fine-Grained Human Evaluation Of Machine Translation Systems: A Case Study On English To Croatian, Filip Klubicka, Antonio Toral, Victor Manuel Sanchez-Cartagena 2018 University of Groningen

Quantitative Fine-Grained Human Evaluation Of Machine Translation Systems: A Case Study On English To Croatian, Filip Klubicka, Antonio Toral, Victor Manuel Sanchez-Cartagena

Articles

This paper presents a quantitative fine-grained manual evaluation approach to comparing the performance of different machine translation (MT) systems. We build upon the well-established Multidimensional Quality Metrics (MQM) error taxonomy and implement a novel method that assesses whether the differences in performance for MQM error types between different MT systems are statistically significant. We conduct a case study for English-to- Croatian, a language direction that involves translating into a morphologically rich language, for which we compare three MT systems belonging to different paradigms: pure phrase-based, factored phrase-based and neural. First, we design an MQM-compliant error taxonomy tailored to the relevant ...


Design Of Event-Triggered Fault-Tolerant Control For Stochastic Systems With Time-Delays, Yi Gao, YunJi Li, Li Peng, Junyu Liu 2018 Engineering Research Center of Internet of Things Technology Applications of Education, Jiangnan University, Wuxi, China

Design Of Event-Triggered Fault-Tolerant Control For Stochastic Systems With Time-Delays, Yi Gao, Yunji Li, Li Peng, Junyu Liu

Articles

This paper proposes two novel, event-triggered fault-tolerant control strategies for a class of stochastic systems with state delays. The plant is disturbed by a Gaussian process, actuator faults, and unknown disturbances. First, a special case about fault signals that are coupled to the unknown disturbances is discussed, and then a fault-tolerant strategy is designed based on an event condition on system states. Subsequently, a send-on-delta transmission framework is established to deal with the problem of fault-tolerant control strategy against fault signals separated from the external disturbances. Two criteria are provided to design feedback controllers in order to guarantee that the ...


Energy Efficient Hybrid Routing Protocol Based On The Artificial Fish Swarm Algorithm And Ant Colony Optimisation For Wsns, Xinlu Li, Brian Keegan, Fredrick Mtenzi 2018 Department of Computer Science, Hefei University, Hefei, China

Energy Efficient Hybrid Routing Protocol Based On The Artificial Fish Swarm Algorithm And Ant Colony Optimisation For Wsns, Xinlu Li, Brian Keegan, Fredrick Mtenzi

Articles

Wireless Sensor Networks (WSNs) are a particular type of distributed self-managed network with limited energy supply and communication ability. The most significant challenge of a routing protocol is the energy consumption and the extension of the network lifetime. Many energy-efficient routing algorithms were inspired by the development of Ant Colony Optimisation (ACO). However, due to the inborn defects, ACO-based routing algorithms have a slow convergence behaviour and are prone to premature, stagnation phenomenon, which hinders further route discovery, especially in a large-scale network. This paper proposes a hybrid routing algorithm by combining the Artificial Fish Swarm Algorithm (AFSA) and ACO ...


Is It Worth It? Budget-Related Evaluation Metrics For Model Selection, Filip Klubicka, Giancarlo Salton, John Kelleher 2018 Dublin Institute of Technology

Is It Worth It? Budget-Related Evaluation Metrics For Model Selection, Filip Klubicka, Giancarlo Salton, John Kelleher

Conference papers

Projects that set out to create a linguistic resource often do so by using a machine learning model that pre-annotates or filters the content that goes through to a human annotator, before going into the final version of the resource. However, available budgets are often limited, and the amount of data that is available exceeds the amount of annotation that can be done. Thus, in order to optimize the benefit from the invested human work, we argue that the decision on which predictive model one should employ depends not only on generalized evaluation metrics, such as accuracy and F-score, but ...


Adapt At Semeval-2018 Task 9: Skip-Gram Word Embeddings For Unsupervised Hypernym Discovery In Specialised Corpora, Alfredo Maldonado, Filip Klubicka 2018 Trinity College Dublin, Ireland

Adapt At Semeval-2018 Task 9: Skip-Gram Word Embeddings For Unsupervised Hypernym Discovery In Specialised Corpora, Alfredo Maldonado, Filip Klubicka

Other resources

This paper describes a simple but competitive unsupervised system for hypernym discovery. The system uses skip-gram word embeddings with negative sampling, trained on specialised corpora. Candidate hypernyms for an input word are predicted based on cosine similar- ity scores. Two sets of word embedding mod- els were trained separately on two specialised corpora: a medical corpus and a music indus- try corpus. Our system scored highest in the medical domain among the competing unsu- pervised systems but performed poorly on the music industry domain. Our approach does not depend on any external data other than raw specialised corpora.


Assessment Of The Accuracy Of Cable Sheath Fault Location Device And Enhancement Of Its Performance, Niall Kennedy, Joseph Kearney, Tom Looby, Ciaran O'Leary 2018 Dublin Institute of Technology

Assessment Of The Accuracy Of Cable Sheath Fault Location Device And Enhancement Of Its Performance, Niall Kennedy, Joseph Kearney, Tom Looby, Ciaran O'Leary

Conference papers

As power system networks are being constantly upgraded and extended, there is a greater importance in the reliable transmission of electrical power and fault finding techniques, especially for cables installed underground. Damage to a cable’s protective sheath can damage a cables life span and also lead to disruption of system operation and loss of supply. This study includes research into the literature and techniques used to locate these faults accurately. Bridge resistance and volt drop measurement techniques are the main methods used by sheath fault location devices to locate faults accurately. This task is made more difficult because such ...


Investigating Smoke Exposure And Chronic Obstructive Pulmonary Disease (Copd) With A Calibrated Agent Based Model (Abm) Of In Vitro Fibroblast Wound Healing., James A. Ratti 2018 Virginia Commonwealth University

Investigating Smoke Exposure And Chronic Obstructive Pulmonary Disease (Copd) With A Calibrated Agent Based Model (Abm) Of In Vitro Fibroblast Wound Healing., James A. Ratti

Theses and Dissertations

COPD is characterized by tissue inflammation and impaired remodeling that suggests fibroblast maintenance of structural homeostasis is dysregulated. Thus, we performed in vitro wound healing experiments on normal and diseased human lung fibroblasts and developed an ABM of fibroblasts closing a scratched monolayer using NetLogo to evaluate differences due to COPD or cigarette smoke condensate exposure. This ABM consists of a rule-set governing the healing response, accounting for cell migration, proliferation, death, activation and senescence rates; along with the effects of heterogeneous activation, phenotypic changes, serum deprivation and exposure to cigarette smoke condensate or bFGF. Simulations were performed to calibrate ...


Navigational Heads-Up Display, Alex Walenchok, Nicholas Seifert, Joshua Reed, Joshua Humphrey 2018 The University of Akron

Navigational Heads-Up Display, Alex Walenchok, Nicholas Seifert, Joshua Reed, Joshua Humphrey

Williams Honors College, Honors Research Projects

One problem drivers face is distraction from looking at their mobile device while navigating rather than watching the road. This problem can be solved with a heads-up display placed directly on the driver’s windshield. By using a mobile device with a custom GPS application, the following design will be able to send GPS data to a device that will display navigational information on a car windshield. The design includes two primary components, a mobile device and a System Unit, where the System Unit is composed of a portable power supply, a single board computer, and a display. For the ...


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