Engineering Commons^™

An Algorithm To Recognize Multi-Stable Behavior From An Ensemble Of Stochastic Simulation Runs, Eduardo Monzon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic biological designers are demanding tools to help with the design and verification process of new biological models. Some of the most common tools available aggregate multiple simulation results into one “clean” trajectory that hopefully is representative of the system’s behavior. However, for systems exhibiting multiple stable states, these techniques fail to show all the possible trajectories of the system. This work introduces a method capable of detecting the presence of more than one “typical” trajectory in a system, which can also be integrated with other available simulation tools.

Enhancing Gan Led Efficiency Through Nano-Gratings And Standing Wave Analysis, Gabriel M. Halpin

Master's Theses

Improving energy efficient lighting is a necessary step in reducing energy consumption.Lighting currently consumes 17% of all U.S. residential and commercial electricity, but a report from the U.S. Office of Energy Efficiency and Renewable Energy projects that switching to LED lighting over the next 20 years will save 46% of electricity used in lighting.GaN LEDs are used for their efficient conversion of electricity to light, but improving GaN efficiency requires optically engineering the chip to extract more light.Total internal reflection limits GaN LED performance since light must approach the chip surface within 23.6° of normal to escape into air.This thesis …

Simulation Of Vertical Axis Wind Turbines With Variable Pitch Foils, L. Damon Woods, John F. Gardner, Kurt S. Myers

Mechanical and Biomedical Engineering Faculty Publications and Presentations

A dynamic computer model of a turbine was developed in MATLAB in order to study the behavior of vertical axis wind turbines (VAWTs) with variable pitch (articulating) foils. The simulation results corroborated the findings of several empirical studies on VAWTs. The model was used to analyze theories of pitch articulation and to inform the discussion on turbine design. Simulations of various models showed that pitch articulation allowed Darrieus-style vertical axis wind turbines to start from rest. Once in motion, the rotor was found to accelerate rapidly to very high rotational velocities. The simulations revealed a plateau region of high efficiency …

Computational Aspects Of The Three-Dimensional Feature-Scale Simulation Of Silicon-Nanowire Field-Effect Sesnsors For Dna Detection, Clemens Heitzinger, Gerhard Klimeck

Gerhard Klimeck

In recent years DNA-sensors, and generally biosensors, with semiconducting transducers were fabricated and characterized. Although the concept of so-called BioFETs was proposed already two decades ago, its realization has become feasible only recently due to advances in process technology. In this paper a comprehensive and rigorous approach to the simulation of silicon-nanowire DNAFETs at the feature-scale is presented. It allows to investigate the feasibility of single-molecule detectors and is used to elucidate the performance that can be expected from sensors with nanowire diameters in the deca-nanometer range. Finally the computational challenges for the simulation of silicon-nanowire DNAsensors are discussed.

Nanohub - Crystal Viewer 2.0, Kevin Margatan, Gerhard Klimeck

Gerhard Klimeck

nanoHUB is an online compilation of tools for simulations. Equipped with 3-D simulations and a capability to solve very complex calculations, nanoHUB provides its users worldwide with various tools to help them finish their assignments. One of the tools available is called a Crystal Viewer Tool, an advanced crystal visualization tool. This tool allows users to generate various crystal types including their every single detail. Currently, a newer version, called Crystal Viewer 2.0, is being tested prior to its release. However, this tool is lacking some important features and a GUI that is not as user friendly as expected. The …

Developing A Crystal Viewer Tool For Nanohub, Osiris V. Ntarugera, Gerhard Klimeck

Gerhard Klimeck

Most materials found in nature have their atoms arranged in a regular and repeated pattern known as crystalline structure; this is particularly true for metals. It is very important to understand the crystal structure of materials in order to predict their properties such as the electric conductivity, heat transfer, and more. Particularly, students and scholars in the field of material science need a way to visualize the different crystal structures. Atomic structures of elements are not visible to the naked eye. In that context, a computer based tool can be used to simulate and to visualize the crystal structures of …

Next Generation Crystal Viewing Tool, Zach Schaffter, Gerhard Klimeck

Gerhard Klimeck

The science and engineering community is limited when it comes to crystal viewing software tools. Each tool lacks in a different area such as customization of structures or visual output. Crystal Viewer 2.0 was created to have all of these features in one program. This one tool simulates virtually any crystal structure with any possible material. The vtkvis widget offers users advanced visual options not seen in any other crystal viewing software. In addition, the powerful engine behind Crystal Viewer 2.0, nanoelectronic modeling 5 or (NEMO5), performs intensive atomic calculations depending on user input. A graphical user interface, or GUI, …

Simulation Of Impulsive Loading On Column Using Inflatable Airbag Technique, Alexander Remennikov, J Y Richard Liew, Kong Sih Ying, K W. Kang

Alex Remennikov

The purpose of this study was to simulate impulsive loading on columns by an innovative lab-based experimental technique that utilises inflatable airbags. Mild and stainless steel hollow sectioin columns with effective lengths of 955mm and under simply supported condition were used in this study.

Simulation Of The Reinforced Concrete Slabs Under Impact Loading, Faham Tahmasebinia, Alexander Remennikov

Alex Remennikov

Many older structures were designed for static loads but more recently there has been a growing awareness that some must be designed to resist both dynamic impact and static loads. An accidental impact load can be caused by mishaps in industry as well as accidents stemming from transportation or man-made disasters. There are number of ways of predicting how an impact load will affect a concrete slab, some of which may be impractical or expensive but because there have been significant developments in technology, numerical techniques rather than experimental approaches have become popular methods for developing detailed responses Therefore, to …

Next Generation Crystal Viewing Tool, Zach Schaffter, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

The science and engineering community is limited when it comes to crystal viewing software tools. Each tool lacks in a different area such as customization of structures or visual output. Crystal Viewer 2.0 was created to have all of these features in one program. This one tool simulates virtually any crystal structure with any possible material. The vtkvis widget offers users advanced visual options not seen in any other crystal viewing software. In addition, the powerful engine behind Crystal Viewer 2.0, nanoelectronic modeling 5 or (NEMO5), performs intensive atomic calculations depending on user input. A graphical user interface, or GUI, …

Thin Electrical Double Layer Simulation Of Micro-Electrochemical Supercapacitors, Kaitlyn Fisher, Guoping Xiong, Timothy S. Fisher

The Summer Undergraduate Research Fellowship (SURF) Symposium

The deteriorating state of the environment has drawn many people to hybrid electric vehicles. Electrochemical micro-supercapacitors are of interest in this field because of their high power density relative to other micro-power sources. However, little is known about how the properties of the electrolyte used affect the performance of such devices. The first step of this investigation was to use thermoreflectance microscopy to measure the temperature change of the electrodes while charging and discharging supercapacitor samples. The components of these samples were graphitic petal electrodes with a Ti/Au covering (for enhanced light reflectance) on a SiO₂ base, with a …

Nanohub - Crystal Viewer 2.0, Kevin Margatan, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

nanoHUB is an online compilation of tools for simulations. Equipped with 3-D simulations and a capability to solve very complex calculations, nanoHUB provides its users worldwide with various tools to help them finish their assignments. One of the tools available is called a Crystal Viewer Tool, an advanced crystal visualization tool. This tool allows users to generate various crystal types including their every single detail. Currently, a newer version, called Crystal Viewer 2.0, is being tested prior to its release. However, this tool is lacking some important features and a GUI that is not as user friendly as expected. The …

Mems Lab Simulation Tool, Oluwatosin D. Adeosun, Sambit Palit, Ankit Jain, Muhammad A. Alam

The Summer Undergraduate Research Fellowship (SURF) Symposium

MEMS actuators have multiple design applications. Understanding their behavior as well as the ability to predict their actuation characteristics and voltage response is important when designing these actuators. In order to know these devices will behave, designers have to solve multiple analytical equations and experiments that can be very time consuming. Over the course of the summer a tool was created on nanoHUB that will allow users to enter information about a MEMS actuator and provide the voltage response of the actuator. To create the tool, scaling equations were first provided for various geometry configurations and the equations were next …

Simulation Of Beam Dynamics For Mems Devices, Saagar Unadkat, Devon Parkos, Alina Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

Microelectromechanical Systems (MEMS) are systems made up of small components to complete a bigger goal. Some of these components can be modeled as small beams, which are anchored at both sides, or as cantilever beams. These beams can be subjected to various forces such as Knudsen Forces, Electrostatic Forces as well as G-loading. These devices have many applications such as sensors, actuators and even as accelerometers for airbags, smart phones and game controllers. Modeling the dynamics of these beams is an important task for the MEMS community, consisting of researchers, fabricators, and designers working on one of the many applications …

Kinetic Monte Carlo Simulations, Jingyuan Liang, R. Edwin García, Ding-Wen (Tony) Chung, David Ely

The Summer Undergraduate Research Fellowship (SURF) Symposium

Kinetic Monte Carlo (kMC) is a set of scientific libraries designed to deploy kMC simulations intended to simulate the time evolution of some processes occurring in nature. kMC is currently allows the user to intuitively generate single component crystal lattices to simulate, post process, and visualize the kinetic Monte Carlo-based atomistic evolution of materials. kMC provides an interface to the Stochastic Parallel PARticle Kinetic Simulator (SPPARKS) [1] and is specifically designed to simulate individual atomic deposition (condensation) and dissolution (evaporation) events, while simultaneously tracking the surface and bulk crystallographic anisotropic diffusion. The main goal of this project is to create …

Thermophotovoltaic System Efficiency Simulation, Qingshuang Chen, Roman Shugayev, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermophotovoltaic (TPV) power systems, which convert heat into electricity using a photovoltaic diode to collect thermal radiation, have attracted increasing attention in recent work. It has recently been proposed that new optical structures such as photonic crystals can significantly improve the efficiency of these devices in two ways. First, the electronic bandgap of the TPV diode should match the photonic bandgap of the emitter, in order to ensure that the majority of emitted photons can be converted. Second, a photonic crystal short-pass optical filter can be added to the front of the TPV diode to send long wavelength photons back …

The Stability And Control Of The Single Track Vehicles, Shyngys Karimov, Martin Corless

The Summer Undergraduate Research Fellowship (SURF) Symposium

Bicycles, motorcycles and scooters are all examples of the single track vehicles. The dynamics of the single track vehicle involve many degrees of freedom and various modes which govern its performance, making a complicated and interesting research topic. Motorcycle in motion can roll, yaw, and steer about the steering axis. It has three main modes which determine the motion and stability of it, they are weave, capsize, and wobble. The motorcycle performance is limited by the behavior of its modes, and if even one of the modes becomes unstable, the vehicle will roll over, and crash. The goal of this …

Developing A Crystal Viewer Tool For Nanohub, Osiris V. Ntarugera, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

Most materials found in nature have their atoms arranged in a regular and repeated pattern known as crystalline structure; this is particularly true for metals. It is very important to understand the crystal structure of materials in order to predict their properties such as the electric conductivity, heat transfer, and more. Particularly, students and scholars in the field of material science need a way to visualize the different crystal structures. Atomic structures of elements are not visible to the naked eye. In that context, a computer based tool can be used to simulate and to visualize the crystal structures of …

Direct Simulation Monte Carlo Simulation Toolkit For Equilibrium (0d) And Planar Couette Flow (1d), Austin I. Saragih, Alina A. Alexeenko

The Summer Undergraduate Research Fellowship (SURF) Symposium

Visualized simulation tool of Direct Simulation Monte Carlo (DSMC) is essential in aeronautical engineering and gas dynamics, by presenting information that can educate engineers and scientists to preliminarily understand the molecular gas dynamics and direct simulation of gas flows. Two educational tools and models are described for rarified gas flows and simulated particle collisions. A 0-Dimensional DSMC in approach to translational equilibrium was developed to simulate the speed distribution over time and the comparison between the final distribution and the Maxwell-Boltzmann distribution. A 1-Dimensional DSMC for Planar Couette flow was also developed to calculate the number of strikes of the …

Python-Based Simulation Tool For Kinetic Monte Carlo, Zaiwei Zhang, R. Edwin García

The Summer Undergraduate Research Fellowship (SURF) Symposium

Simulation tools are highly needed for testing or designing nanotechnology in university research projects.The problem in the current simulation tool used in our research, which is conducted by Prof.Garcia in MSE department at Purdue, is that users cannot observe the changing numbers of diffusivities during Vacancy Diffusion simulations between different materials. Also, there is no Graphic User Interface for the simulation tools.To solve the problem, the Virtual Kinetics of Materials Laboratory program is used to create the Graphic User Interface. Also, GTK+ toolkit has been used to create a pop-up window displaying updated diffusivities during the simulation. For user purpose, …

Developing A Framework For Determining The Contribution Of Transportation Project To Sustainable Development, Karim Ahmed Abdel Warith

Open Access Dissertations

In the past few years, stakeholders in the transportation industry have been concerned with sustainability. However, transportation decision makers have had difficulty incorporating sustainability into transportation infrastructure decisions. This is mainly attributed to the vagueness of the term. Incorporating sustainability into transportation decision making has been a desire put forth by engineers for that past 10 years. However, with no apparent method of defining sustainability, designers and decision makers have not been able to fulfill this desire.

This investigation attempts to define sustainability in a comprehensive and quantitative manner. The research proposes a new methodology that relies on the objective …

Technical Subtopic 2.1: Modeling Variable Refrigerant Flow Heat Pump And Heat Recovery Equipment In Energyplus, Florida Solar Energy Center, Richard Raustad

FSEC Energy Research Center®

The University of Central Florida/Florida Solar Energy Center, in cooperation with the Electric Power Research Institute and several variable-refrigerant-flow air conditioning (VRF AC) manufacturers, provided a detailed computer model for a VRF AC system in the United States Department of Energy's (U.S. DOE) EnergyPlus' building energy simulation tool. No other simulation tool currently has the capability to accurately model this state-of-the-art VRF heating, ventilating, and air conditioning (HVAC) equipment. Detailed laboratory testing and field demonstrations were performed to measure equipment performance and compare this performance with that predicted by the use of this new model through computer simulation.

This project …

Computational Modeling And Experimental Study On Optical Microresonators Using Optimal Spherical Structure For Chemical Sensing, Hanzheng Wang, Lei Yuan, Jie Huang, Xinwei Lan, Cheol-Woon Kim, Lan Jiang, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Chemical sensors based on optical microresonators have been demonstrated highly sensitive by monitoring the refractive index (RI) changes in the surrounding area near the resonator surface. In an optical resonator, the Whispering Gallery Modes (WGMs) with high quality (Q) factor supported by the spherical symmetric structure interacts with the contiguous background through evanescent field. Highly sensitive detection can be realized because of the long lifetime of the photons. The computational models of solid glass microspheres and hollow glass spheres with porous wall (PW-HGM) were established. These two types of microresonators were studied through simulations. The PWHGM resonator was proved as …

Aspen Plus Simulation Of Biomass Gasification In A Steam Blown Dual Fluidised Bed, Wayne Doherty, Anthony Reynolds, David Kennedy

Book/Book Chapters

The efficient utilisation of biomass resources is of utmost importance. Biomass gasification offers much higher efficiencies than combustion. Gasification is a process in which a fuel is converted to a combustible gas (syngas). A dual fluidised bed gasifier known as the fast internally circulating fluidised bed (FICFB) was selected. It has been demonstrated at industrial scale and data is readily available for model validation. An Aspen Plus model was developed to simulate the FICFB gasifier. The model is based on Gibbs free energy minimisation and the restricted equilibrium method was used to calibrate it. The model has been validated and …

Real-Time Visualization Of Finite Element Models Using Surrogate Modeling Methods, Ryan C. Heap

Theses and Dissertations

Finite element analysis (FEA) software is used to obtain linear and non-linear solutions to one, two, and three-dimensional (3-D) geometric problems that will see a particular load and constraint case when put into service. Parametric FEA models are commonly used in iterative design processes in order to obtain an optimum model given a set of loads, constraints, objectives, and design parameters to vary. In some instances it is desirable for a designer to obtain some intuition about how changes in design parameters can affect the FEA solution of interest, before simply sending the model through the optimization loop. This could …

Using Real-Time Location Systems & Simulation Modeling To Improve Healthcare, Colby Thomas Mattie

Masters Theses

In the healthcare industry, facility managers often find themselves with limited resources, lack of timely data, and unexpected crises that they have to respond too. Their options are based on hastily made assumptions and a limited understanding of all implications of the problems at hand. This scenario has become a concerning issue for the healthcare industry where problems can arise at any time and every minute counts. The healthcare industry is also littered with wasteful processes and regulations that increase the cost for physicians and facility operators and decrease the overall care for the patients. This is very evident in …

A Methodology For Designing Airports For Enhanced Security Using Simulation, Oliver Nwofia, Christopher A. Chung

Journal of Aviation Technology and Engineering

With the advent of the new security measures, today’s airports have become increasingly complex and congested. Air and passenger traffic continues to increase; consequently, the need for intelligent design concepts is required. Unlike all other existing airport designs that focused exclusively on operational performance, this study focused on the development of a new airport terminal design methodology that takes a proactive approach to minimizing the effects of security disruptions while simultaneously maximizing operational performance and passenger flow. The study addressed the impact of security operations on both the design of airport facilities and passenger flows, and discussed options and scenarios …

Dynamics And Dislodgment From Pore Constrictions Of A Trapped Nonwetting Droplet Stimulated By Seismic Waves, Wen Deng, M. Bayani Cardenas

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Seismic waves affect fluid flow and transport processes in porous media. Therefore, quantitative understanding of the role of seismic waves in subsurface hydrodynamics is important for the development of practical applications and prediction of natural phenomena. We present a theoretical fluid dynamics model to describe how low-frequency elastic waves mobilize isolated droplets trapped in pores by capillary resistance. The ability of the theoretical model to predict the critical mobilization amplitudes (A_c) and the displacement dynamics of the nonwetting droplet are validated against computational fluid dynamics (CFD) simulations. Our theory has the advantage of rapid calculation of A_{c …}

The Effects Of Mismatches And Probe Tethering Configurations On The Stability Of Dna Duplexes On Surfaces, Kyle Evan Pratt

Theses and Dissertations

DNA microarrays are chip-based, analysis tools which can perform hundreds of thousands of parallel assays to determine the identity of genes or gene expression levels present in a sample. They have been identified as a key technology in genomic sciences and emergent medical techniques; however, despite their abundant use in research laboratories, microarrays have not been used in the clinical setting to the fullest potential due to the difficulty of obtaining reproducible results. Microarrays work on the principle of DNA hybridization, and can only be as accurate as this process is robust. Fundamental, molecular-level understanding of hybridization on surfaces is …

Using Discrete Event Simulation To Improve The Patient Care Process In The Emergency Department Of A Rural Kentucky Hospital., Molly Cassaro Jones

Electronic Theses and Dissertations

The patient care process of a rural Kentucky hospital is a complex process that must be flexible in order to deal with a large variety of patient needs and a fluctuating patient volume where all patients are unscheduled. A simulation model of an average month in the emergency department was built using the Arena Simulation package. Methods for creating a simulation using Arena are included in this work. Statistics were generated from a number of different sources to create an accurate representation of the model. The Hospital reporting shows a need to improve on two quality measures being tracked, the …