Engineering Commons^™

Impact-Acoustic Evaluation Method Of Internal Crack In Rubber Composite Structure, Qin Shen

All Dissertations

The main objective of this work is to investigate the impact acoustic method as a means of nondestructive testing (NDT) for internal cracks in a rubber composite structure, such as that found in a tire. As demonstrated in this dissertation, this approach is an effective and economical alternative to the current NDT methods for tires casing integrity inspection. There are two separate aspects of the impact acoustic signals considered in this work: the impact force signal and the resultant acoustic signal. First, a contact dynamics model is developed based on the Hertz’s impact theory and modified for rubber composite materials. …

Design And Implementation Of Wireless Point-Of-Care Health Monitoring Systems: Diagnosis For Sleep Disorders And Cardiovascular Diseases, Se Chang Oh

Graduate Theses and Dissertations

Chronic sleep disorders are present in 40 million people in the United States. More than 25 million people remain undiagnosed and untreated, which accounts for over $22 billion in unnecessary healthcare costs. In addition, another major chronic disease is the heart diseases which cause 23.8% of the deaths in the United States. Thus, there is a need for a low cost, reliable, and ubiquitous patient monitoring system. A remote point-of-care system can satisfy this need by providing real time monitoring of the patient's health condition at remote places. However, the currently available POC systems have some drawbacks; the fixed number …

A Novel Batch-Processing Method For Accurate Crystallographic Axis Alignment, Jun Hyun Han, Shankar Radhakrishnan, Chung-Hoon Lee

Electrical and Computer Engineering Faculty Research and Publications

A new method for the accurate alignment of lithographically-defined patterns to the crystallographic axes of substrates is presented. We provide a lower (worst-case) limit of the achievable high aspect ratio using anisotropic wet chemical silicon etch for deep trenches. The method uses the fact that the intensity of light reflected from two sets of gratings, one on the photomask and the other on the substrate, is a sharp function of their relative angular misalignment. By using pre-etched gratings on the substrate formed by wet anisotropic etching, alignment accuracies better than 50 millidegrees with respect to silicon crystallographic axes have been …

Influence Of Microstructure On Thermoelastic Wave Propagation, Arkadi Berezovski, Mihhail Berezovski

Publications

Numerical simulations of the thermoelastic response of a microstructured material on a thermal loading are performed in the one-dimensional setting to examine the influence of temperature gradient effects at the microstructure level predicted by the thermoelastic description of microstructured solids (Berezovski et al. in J. Therm. Stress. 34:413–430, 2011). The system of equations consisting of a hyperbolic equation of motion, a parabolic macroscopic heat conduction equation, and a hyperbolic evolution equation for the microtemperature is solved by a finite-volume numerical scheme. Effects of microtemperature gradients exhibit themselves on the macrolevel due to the coupling of equations of the macromotion …

Determining Appropriate Heating And Cooling Thermostat Set Points For Building Energy Simulations For Residential Buildings In North America, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Existing building energy simulation tools have a purported tendency to over-predict heating use and, in some cases, to under-predict cooling use, an outcome often attributed to inappropriate assumptions about thermostat management. As a result, a systematic review was conducted for the purposes of determining typical heating and cooling set points for single-family houses in North America. The preliminary consensus results provide an empirical basis for establishing typical inputs for building energy simulation models, increasing prediction accuracy of heating and cooling loads. The results of this review have been applied as default values in the Lawrence Berkeley National Laboratory's Home Energy …

Electrical Characterization Of Gold Functionalized Dna Origami Nanotubes, Christopher Vinhtroung Buu

Boise State University Theses and Dissertations

Conductivity types (i.e., insulator, semiconductor, and conductor) can be tuned by varying the size of metallic nanoparticles. DNA origami, a molecular self-assembly technique, has promise to programmatically self-assemble nanoparticles (NPs) with nanometer precision. The work presented here demonstrates the programmatic self-assembly of AuNPs on DNA origami nanotubes (NTs). DNA origami NTs were also functionalized with positively charged Au clusters. DNA origami NTs, both bare and functionalized with Au, were electrically characterized using DC current-voltage (DC-IV) measurements. The measurements showed that bare, undecorated DNA NTs behaved as an insulator, whereas linear, ohmic conductivity was observed for Au enhanced Au decorated NTs. …

Simulation Of Vawt And Hydrokinetic Turbines With Variable Pitch Foils, Lindsay Damon Woods

Boise State University Theses and Dissertations

A dynamic computer model of a turbine was developed in MATLAB in order to study the behavior of vertical axis wind and hydrokinetic turbines with articulating foils. The simulation results corroborated the findings of several empirical studies on various turbines in both wind and water currents. The model was used to analyze theories of pitch articulation and to inform the discussion on turbine design. Several new patents and proposed configurations were tested. Simulation results showed that pitch articulation allowed Darrieus-style vertical axis wind turbines to start from rest. The tip speed ratio was found to increase rapidly, carrying the turbine …

A Memristor-Based Neuromorphic Computing Application, Adrian Rothenbuhler

Boise State University Theses and Dissertations

Artificial neural networks have recently received renewed interest because of the discovery of the memristor. The memristor is the fourth basic circuit element, hypothesized to exist by Leon Chua in 1971 and physically realized in 2008. The two-terminal device acts like a resistor with memory and is therefore of great interest for use as a synapse in hardware ANNs. Recent advances in memristor technology allowed these devices to migrate from the experimental stage to the application stage.

This Master's thesis presents the development of a threshold logic gate (TLG), which is a special case of an ANN, implemented with discrete …

The Design, Fabrication, And Pressure Testing Of A Low-Temperature Co-Fired Ceramic Electric Propulsion Thruster, Derek J. Reis

Boise State University Theses and Dissertations

Electric thrusters have been used for many years for orbital station-keeping and propulsion. As technology advances, smaller satellites are possible that require less thrust. The resulting miniature electric thrusters need low-weight and compact designs. This thesis specifies the design, fabrication, and testing of a thruster and its fluid delivery system designed for use with a micro-satellite weighing less than fifty kilograms.

The advent of Micro-Electro-Mechanical Systems (MEMS) has sparked a new market with incredibly small scale designs. Using this technology with Low-Temperature Co-fired Ceramic (LTCC) materials has spawned the new distinction of Ceramic Micro-Electro-Mechanical Systems (C-MEMS). The thruster body is …

Toward Characterization Of Diseased Vascular Structures Using Noncontact Photoacoustic And Laser-Ultrasound Imaging: A Phantom Study, Jami Lynne Johnson

Boise State University Theses and Dissertations

Visualizing and characterizing atherosclerotic plaques is important in determining the vulnerability of a plaque to rupture. To evaluate rupture risk, several compositional factors should be evaluated, including inflammation, the presence and size of lipid pools, thickness of the fibrous cap, and calcification. Currently, a need exists for an imaging modality that can detect each of these factors in a safe, noninvasive manner with high resolution and contrast at clinically relevant depths. Photoacoustic imaging is a growing field that has the potential to improve plaque diagnosis. Spectroscopic methods have shown promise toward detection of constituents of plaque with unique optical absorption …

Communication Artifacts And Interaction Evaluation For Requirements Engineering, Miloslava Plachkinova

UNLV Theses, Dissertations, Professional Papers, and Capstones

This paper aims to answer an important question regarding the development of new information systems (IS): "What is the predominant factor for the selection of communication artifacts for requirements engineering (RE)?". Many researchers have focused on the RE and communication as separate disciplines, but little or no research addressed the RE communication issues. These problems are important because they often lead to misunderstanding and misinterpretation of the gathered requirements. We develop expectations about the RE communication process based on prior literature from both disciplines and we test them through several case studies. Our methodology consists of analysis of six case …

Investigation Of Crashes And Identifying The Best Practices For Setting Up Speed Zones In Towns Along Rural Highways In Nevada, Krishna Prasad Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

In 2010, 51,664 crashes occurred in Nevada. Only about 9% of those crashes occurred in rural areas of the state. However, if only fatal crashes are considered, 41% of those fatal crashes occurred in rural areas. Generally, speed zones are provided in towns along rural highways to reduce speed-related crashes. However, a guideline is necessary for a consistent procedure to setup speed zones throughout the state. The main objectives of this study are to determine factors associated with crashes and to identify the best practices for setting up speed zones in towns along rural highways.

Eleven towns along rural highways …

Highly Sensitive Method For Detecting And Separating Pathogens Using Paramagnetic Particles And A Micro-Fluidic System, William Ryan

Biomedical Engineering Undergraduate Honors Theses

Water is one of the most important compounds on Earth. If a water supply is contaminated with a pathogen, it can have devastating results to an individual or a community. This research is directed at constructing an easily reproducible procedure that could increase the sensitivity of detecting and separating bacteria from the current limits of about 100 cells to 10-20 cells per sample with a ultimate goal of a single cell detection. Here, we report a micro-fluidic system to magnetically capture pathogenic bacteria in water followed by rapid impedance detection using Escherichia coli K-12 as a model bacterium. Paramagnetic beads …

Comparing Decellularized Muscle Tissue With An Engineered Muscle Biomaterial, Katelin Cherry

Biomedical Engineering Undergraduate Honors Theses

Decellularized tissues composed of extracellular matrix are commonly used for tissue transplantations but this method has many limitations. An alternative approach is to create an extracellular matrix by seeding degradable foams with cells, culturing these foams to allow extracellular matrix to be secreted from the cells, then washing away the degradable foam to collect the material that is produced. This study was interested in comparing decellularized skeletal muscle tissue to an engineered biomaterial that was seeded with skeletal muscle myoblast cells. Collagen content of decellularized tissue and engineered biomaterial were quantified using a hydroxyproline assay to compare the two samples. …

Rapid Detection And Quantification Of Mycobacterium Tuberculosis Using Single-Based Extension And Capillary Electrophoresis, Anh Vu

Biomedical Engineering Undergraduate Honors Theses

In 1993, the World Health Organization (WHO) has declared tuberculosis (TB) a global emergency. Since then, more than 30 million lives have been claimed by that world-wide epidemic. In 2011, 8.7 million people “felt ill” because of TB and not all TB cases were reported to clinicians. Therefore, it is important to accurately identify TB patients by developing a diagnostic method that is sensitive, fast, and cost-effective. However, conventional methods have not met those criteria because they either require lengthy procedures or may misdiagnose TB cases. Hence, the automated Xpert MTB/RIF, endorsed by WHO in 2010, was developed and so …

Gesture Based Home Automation For The Physically Disabled, Alexander Hugh Nelson

Graduate Theses and Dissertations

Paralysis and motor-impairments can greatly reduce the autonomy and quality of life of a patient while presenting a major recurring cost in home-healthcare. Augmented with a non-invasive wearable sensor system and home-automation equipment, the patient can regain a level of autonomy at a fraction of the cost of home nurses. A system which utilizes sensor fusion, low-power digital components, and smartphone cellular capabilities can extend the usefulness of such a system to allow greater adaptivity for patients with various needs. This thesis develops such a system as a Bluetooth enabled glove device which communicates with a remote web server to …

Cost Distribution Analysis Of Remote Monitoring System Use In The Treatment Of Chronic Diseases, Adeola Yusuf

Industrial Engineering Undergraduate Honors Theses

The cost of the treatment of chronic diseases is very high and this has a huge impact on the health-care system. Several factors contribute to this high cost. Some of these include the direct costs of treatment and the costs of several potential complications that arise as a result of the presence of other diseases. The goal of this study is to evaluate a cost-effective way of managing some of the common chronic diseases by analyzing the potential cost savings of utilizing remote monitoring systems (RMS) as opposed to the use of the traditional bundle (which includes regular visits to …

New Effects Of Aging And Lattice Intercalation On Surface Properties Of Titanate Nanobelts, Roger Williams

Graduate Theses and Dissertations

Titanate nanobelts (NBs) have structural characteristics beyond that of clays. Due to a negatively charged lattice matrix of edge-shared TiO6-octahedra, the location of intercalated cations within the interlayer space may dictate the charge-conductions. This environment may in turn govern the lattice-framework's stability and surface properties, based upon our preliminary

data.

On that basis, these nanomaterials have been found in our lab to possess superb biological compatibility that is closely related to the types of the intercalated cations. In addition, a prolonged agitation was proven to enable us to manipulate the titanate NBs' length. In a parallel study, a ripening was …

Design, Layout, And Testing Of A Silicon Carbide-Based Under Voltage Lock-Out Circuit, Michael Dalan Glover

Graduate Theses and Dissertations

Silicon carbide-based power devices play an increasingly important role in modern power conversion systems. Finding a means to reduce the size and complexity of these systems by even incremental amounts can have a significant impact on cost and reliability. One approach to achieving this goal is the die-level integration of gate driver circuitry with the SiC power devices. Aside from cost reductions, there are significant advantages to the integration of the gate driver circuits with the power devices. By integrating the gate driver circuitry with the power devices, the parasitic inductances traditionally seen between the gate driver and the switching …

Directed Percolation And The Abstract Tile Assembly Model, Tyler Garrett Moore

Graduate Theses and Dissertations

Self-assembly is a process by which simple components build complex structures through local interactions. Directed percolation is a statistical physical model for describing competitive spreading processes on lattices. The author describes an algorithm which can transform a tile assembly system in the abstract Tile Assembly Model into a directed percolation problem, and then shows simulations of the aTAM which support this algorithm. The author also investigates two new constructs designed for Erik Winfree's abstract Tile Assembly Model called the NULL tile and temperature 1.5. These constructs aid the translation between self-assembly and directed percolation and may assist self-assembly researchers in …

Design And Fundamental Understanding Of Minimum Quantity Lubrication (Mql) Assisted Grinding Using Advanced Nanolubricants, Parash Kalita

Graduate Theses and Dissertations

Abrasive grinding is widely used across manufacturing industry for finishing parts and components requiring smooth superficial textures and precise dimensional tolerances and accuracy. Unlike any other machining operations, the complex thermo-mechanical processes during grinding produce excessive friction-induced energy consumption, heat, and intense contact seizures. Lubrication and cooling from grinding fluids is crucial in minimizing the deleterious effects of friction and heat to maximize the output part quality and process efficiency. The conventional flood grinding approach of an uneconomical application of large quantities of chemically active fluids has been found ineffective to provide sufficient lubrication and produces waste streams and pollutants …

Computational Tire Models And Their Effectiveness, Andrew Wheeler

Mechanical Engineering Undergraduate Honors Theses

This paper describes the advantages, disadvantages, and complications that arise during the modeling, simulation, and analysis of tire models using MSC’s Adams/Car software. Due to the complexity of the testing, this paper was limited to a handful of tests. This included putting a template Formula SAE vehicle through simulations on a constant radius skidpad, performing a high stress longitudinal acceleration, a fish-hook maneuver, and a step-steer maneuver. These tests were analyzed and compared to current understandings of the model’s accuracy and validity. Of the six different models tested, the FTire model proved to be the best performing. The main Pacejka …

Design And Construction Of An Experiment For The Investigation Of The Effects Of Gust On Flapping Wing Micro Air Vehicle Power Consumption, Brett Hiller

Mechanical Engineering Undergraduate Honors Theses

In recent years, the promising nature of flapping wing flight has led researchers to investigate the wing morphology and unsteady wing aerodynamics found in insects to aid in the design of modern micro air vehicles (MAVs). A high-fidelity flapping wing MAV could achieve high mobility, hovering stability, increased stealth, and efficient flight at low speeds. These characteristics offer a viable solution to the operational requirements for the typical hazardous and dynamic environments encountered during flight. While the kinematics and morphology of flapping wings are well-understood, significant research has yet to be completed with respect to the control and power requirements …

Optimization Of Automated Temperature Measurement System For Formed Meat Products, Tyler Norman

Mechanical Engineering Undergraduate Honors Theses

The Federal Safety and Inspection Services in accordance with United States Department of Agriculture require that formed meat products be cooked to a specified minimum internal temperature in order to eliminate the possible presence of harmful bacteria. The current system of verifying the internal temperatures of formed meat products consists of manually inserting a temperature probe into the selected sample as it exits the oven. Creating an automated system that measures and records the internal temperatures of formed meat samples as they exit the oven along a meat processing line has been the topic of an ongoing research. The most …

Exploration Into Properties Of Molybdenum Disulfide Using Atomistic Simulation, Joseph Simpson

Mechanical Engineering Undergraduate Honors Theses

Molybdenum disulfide (MoS2) has a lamellar crystal structure, which makes it ideal for use as a solid lubricant. Transmission electron microscope (TEM) images have shown that line defects exist within the lattice of mechanically deformed MoS2, but the physical mechanisms which lead to the formation of these defects are unknown. The two central objectives of this research are to use molecular dynamics simulations to study the effects of tensile deformation on both single layer and bulk MoS2 and explore the properties of line defects in an otherwise perfect lattice of MoS2. Under tensile loading, molecular dynamics simulations show a multi-stage …

A Polarizable Reactive Force Field For Water To Enable Molecular Dynamics Simulations Of Proton Transport, Abhishek Asthana, Dean R. Wheeler

Faculty Publications

A new polarizable water model is developed for molecular dynamics (MD) simulations of the proton transport process. The interatomic potential model has three important submodels corresponding to electrostatic interactions, making and breaking of covalent bonds, and treatment of electron exchange and correlation through a van der Waals potential. A polarizable diffuse charge density function was used to describe Coulombic interactions between atoms. Most of the model parameters were obtained from ab initio data for a lone water molecule. Molecules respond realistically to their electrochemical environment by the use of coupled fluctuating charge and fluctuating dipole dynamics, which controlled the charge …

Relative Navigation Approach For Vision-Based Aerial Gps-Denied Navigation, Robert C. Leishman, Timothy Mclain, Randal W. Beard

Faculty Publications

GPS-denied aerial flight is a popular research topic. The problem is challenging and requires knowledge of complex elements from many distinct disciplines. Additionally, aerial vehicles can present challenging constraints such as stringent payload limitations and fast vehicle dynamics. In this paper we propose a new architecture to simplify some of the challenges that constrain GPS-denied aerial flight. At the core, the approach combines visual graph-SLAM with a multiplicative extended Kalman filter. More importantly, for the front end we depart from the common practice of estimating global states and instead keep the position and yaw states of the MEKF relative to …

Tesla: An Energy-Saving Agent That Leverages Schedule Flexibility, Jun Young Kwak, Pradeep Varakantham, Rajiv Maheswaran, Burcin Becerik-Gerber, Milind Tambe

Research Collection School Of Computing and Information Systems

This innovative application paper presents TESLA, an agent-based application for optimizing the energy use in commercial buildings. TESLA’s key insight is that adding flexibility to event/meeting schedules can lead to significant energy savings. TESLA provides three key contributions: (i) three online scheduling algorithms that consider flexibility of people’s preferences for energyefficient scheduling of incrementally/dynamically arriving meetings and events; (ii) an algorithm to effectively identify key meetings that lead to significant energy savings by adjusting their flexibility; and (iii) surveys of real users that indicate that TESLA’s assumptions exist in practice. TESLA was evaluated on data of over 110,000 meetings held …

Anonymous Authentication Of Visitors For Mobile Crowd Sensing At Amusement Parks, Divyan Konidala, Robert H. Deng, Yingjiu Li, Hoong Chuin Lau, Stephen Fienberg

Research Collection School Of Computing and Information Systems

In this paper we focus on authentication and privacy aspects of an application scenario that utilizes mobile crowd sensing for the benefit of amusement park operators and their visitors. The scenario involves a mobile app that gathers visitors’ demographic details, preferences, and current location coordinates, and sends them to the park’s sever for various analyses. These analyses assist the park operators to efficiently deploy their resources, estimate waiting times and queue lengths, and understand the behavior of individual visitors and groups. The app server also offers visitors optimal recommendations on routes and attractions for an improved dynamic experience and minimized …

The Geometry And Sensitivity Of Ion-Beam Sculpted Nanopores For Single Molecule Dna Analysis, Ryan Connor Rollings

Graduate Theses and Dissertations

In this dissertation, the relationship between the geometry of ion-beam sculpted solid-state nanopores and their ability to analyze single DNA molecules using resistive pulse sensing is investigated. To accomplish this, the three dimensional shape of the nanopore is determined using energy filtered and tomographic transmission electron microscopy. It is shown that this information enables the prediction of the ionic current passing through a voltage biased nanopore and improves the prediction of the magnitude of current drop signals when the nanopore interacts with single DNA molecules. The dimensional stability of nanopores in solution is monitored using this information and is improved …