Engineering Commons^™

Impact Of Chain Architecture On The Thickness Dependence Of Physical Aging Rate Of Thin Polystyrene Films, Gregory Brown, Elizabeth Lewis, Bryan D. Vogt

Williams Honors College, Honors Research Projects

The dynamics of polymer thin films have been demonstrated to be significantly altered from the bulk, but the origins of such differences are not well defined. In this work, we seek to understand the differences in the structural dynamics (or physical aging) of polystyrene (PS) through branching and other well defined architectures (comb and centipede). The aging dynamics of ultrathin films (< 30 nm) differ from relatively thick films (100-150nm) with linear PS thin films aging more rapidly than the relatively “bulk-like” thick films. Ellipsometric measurements are used to characterize the physical aging rate of the films. The change in film thickness and refractive index as the films are held below the glass transition temperature (T_g) provides a simple measure of the physical aging. In this study, four different architectures (linear, comb, 4 arm star, and centipede) will be investigated. For each PS architecture, the aging rate will be determined for film thickness ranging ...

Stability Analysis Of A More General Class Of Systems With Delay-Dependent Coefficients, Chi Jin, Keqin Gu, Islam Boussaada, Silviu-Iulian Niculescu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper presents a systematic method to analyse the stability of systems with single delay in which the coefficient polynomials of the characteristic equation depend on the delay. Such systems often arise in, for example, life science and engineering systems. A method to analyze such systems was presented by Beretta and Kuang in a 2002 paper, but with some very restrictive assumptions. This work extends their results to the general case with the exception of some degenerate cases. It is found that a much richer behavior is possible when the restrictive assumptions are removed. The interval of interest for the ...

Development And Testing Of Additively Manufactured Aerospike Nozzles For Small Satellite Propulsion, Isaac W. Armstrong

All Graduate Theses and Dissertations

Automatic altitude compensation has been a holy grail of rocket propulsion for decades. Current state-of-the-art bell nozzles see large performance decreases at low altitudes, limiting rocket designs, shrinking payloads, and overall increasing costs. Aerospike nozzles are an old idea from the 1960’s that provide superior altitude-compensating performance and enhanced performance in vacuum, but have survivability issues that have stopped their application in satellite propulsion systems. A growing need for CubeSat propulsion systems provides the impetus to study aerospike nozzles in this application. This study built two aerospike nozzles using modern 3D metal printing techniques to test aerospikes at a ...

Comparison Of Induced And Parasitic Drag On Wings With Minimum Induced Drag, Sarah A. Abdel-Motaleb

All Graduate Plan B and other Reports

Minimizing the induced drag for steady level flight is a variational problem that requires solving for the optimum lift distribution given a set of design constraints. From lifting-line theory, minimizing the induced drag is, in part, achieved by varying the Fourier coefficients used to describe the section lift. The elliptic lift distribution minimizes the induced drag for a wing with fixed weight and wingspan by setting all but the first coefficient to zero. If wingspan is allowed to vary, a negative third Fourier coefficient is utilized to reach an optimum lift distribution that further reduces the induced drag for stress-limited ...

Investigation Of Thermoplastic Polymers And Their Blends For Use In Hybrid Rocket Combustion, Spencer D. Mathias

All Graduate Theses and Dissertations

This thesis set out to find a blend of thermoplastics that had better combustion properties than the current ABS (acrylonitrile butadiene styrene) plastic or “Lego ^TM plastic” used by Utah State University. The current work is in an effort to eliminate toxic propellants from small space applications. High and low density polyethylene plastics were used because they are common plastic waste items. In this way rocket fuel can be made from these items to reduce the waste found in landfills. Three plastics were considered for replacement and as mixture components with the ABS plastic, namely low and high density polyethylene ...

Hydrodeoxygenation Of Pinyon-Juniper Catalytic Pyrolysis Oil, Hossein Jahromi

All Graduate Theses and Dissertations

Catalytic hydrodeoxygenation (HDO), is an effective process to convert oxygenated compounds to hydrocarbons. This process is widely used for improving the negative properties of biomass-derived pyrolysis oils (bio-oils) such as high acidity, poor stability, and low heating value. During this process oxygen is removed from the bio-oil in the form of water, thus the liquid product of HDO process consists of aqueous phase and hydrocarbon phase that can be easily separated. Synthesis of efficient HDO catalyst has been a major challenge in the field of bio-oil upgrading. Red mud, which is an alkaline waste from alumina industry was used to ...

Pressure Loss Coefficients For Large Mitered Elbows With Diameters Ranging From 36-Inches To 144-Inches, Hayden J. Coombs

All Graduate Theses and Dissertations

When designing a pipeline system, it is important to understand the pressure losses that will occur within the system. One common source of pressure loss is from elbow pipe fittings. There is extensive research available for pressure loss coefficients of elbow pipe fittings, but the research is derived from elbows with relatively smaller pipe diameters. The purpose of this research is to investigate pressure losses associated with larger diameter mitered elbows (36-inches to 144-inches). The dimensions for all mitered elbows considered in this research follow ANSI/AWWA C208-17 recommendations (AWWA 2017).

Due to the large size of the mitered elbows ...

Sensor Intrusion Detection In Control Systems Using Estimation Theory, Jiayi Su

Master's Theses (2009 -)

In this thesis, two different approaches to sensor intrusion detection are presented. In the first approach, an estimation algorithm using a bank of Kalman Filters is designed that is capable of estimating the intrusion signal when sensors are affected in control systems. The mathematical models of the control system will be estabilished and the system measurement will be shown and after that, various false signals, such as constant-type and ramp-type signal, will be selected as the intrusion signal to affect the system output mentioned above. The system measurement will be tested based on a bank of Kalman Filters. The probabilities ...

Synopsis Of Engineers Without Borders (Ewb) Trip, Guatemala January 5 To January 12, 2019, Willis Weight

Engineers Without Borders

The Carroll Guatemala Engineers Without Borders (EWB) team assembled at a variety of locations from around the western USA before traveling together as a group into Guatemala City from a flight from Los Angeles. The flight from Los Angeles on Saturday morning departed about 11:00 AM local time. Two of us departed about 6:00 am from the Missoula airport (Willis Weight and Kennedy Bahm) and the following students: Ian Kirby, Josiah Groux, Amelia Schuver, Ericka Seehafer, Mary Van Dyke (health and safety officer), and Amber Pickering (project leader) came in from Portland, Seattle, and SLC). Professional mentor Ryan ...

Passive Compliance Control Of Redundant Serial Manipulators, Jacob J. Rice

Dissertations (2009 -)

Current industrial robotic manipulators, and even state of the art robotic manipulators, are slower and less reliable than humans at executing constrained manipulation tasks, tasks where motion is constrained in some direction (e.g., opening a door, turning a crank, polishing a surface, or assembling parts). Many constrained manipulation tasks are still performed by people because robots do not have the manipulation ability to reliably interact with a stiff environment, for which even small commanded position error yields very high contact forces in the constrained directions. Contact forces can be regulated using compliance control, in which the multi-directional elastic behavior ...

Detection And Characterization Of Actuator Attacks Using Kalman Filter Estimation, Yuqin Weng

Master's Theses (2009 -)

In this thesis, two discrete-time control systems subject to noise, are modeled, analyzed and estimated. These systems are then subjected to attack by false signals such as constant and ramp signals. In order to find out how and when the control systems are being attacked by the false signals, several detection algorithms are applied to the systems. This work focuses on actuator attack detection. To detect the presence of false actuator signals, a bank of Kalman filters is set up which uses adaptive estimation and conditional probability density functions for detecting the false signals. The individual Kalman filters are each ...

Automotive Intrusion Detection Based On Constant Can Message Frequencies Across Vehicle Driving Modes, Clinton Young, Habeeb Olufowobi, Gedare Bloom, Joseph Zambreno

Electrical and Computer Engineering Conference Papers, Posters and Presentations

The modern automobile relies on numerous electronic control units communicating over the de facto standard of the controller area network (CAN) bus. This communication network was not developed with cybersecurity in mind. Many methods based on constant time intervals between messages have been proposed to address this lack of security issue with the CAN bus. However, these existing methods may struggle to handle variable time intervals between messages during transitions of vehicle driving modes. This paper proposes a simple and cost-effective method to ensure the security of the CAN bus that is based on constant message frequencies across vehicle driving ...

Anomaly Detection Approach Using Adaptive Cumulative Sum Algorithm For Controller Area Network, Habeeb Olufowobi, Uchenna Ezeobi, Eric Muhati, Gaylon Robinson, Clinton Young, Joseph Zambreno, Gedare Bloom

Electrical and Computer Engineering Conference Papers, Posters and Presentations

The modern vehicle has transformed from a purely mechanical system to a system that embeds several electronic devices. These devices communicate through the in-vehicle network for enhanced safety and comfort but are vulnerable to cyber-physical risks and attacks. A well-known technique of detecting these attacks and unusual events is by using intrusion detection systems. Anomalies in the network occur at unknown points and produce abrupt changes in the statistical features of the message stream. In this paper, we propose an anomaly-based intrusion detection approach using the cumulative sum (CUSUM) change-point detection algorithm to detect data injection attacks on the controller ...

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Motion-Based Design Approach For A Novel Variable Friction Cladding Connection Used In Wind Hazard Mitigation, Yongqiang Gong, Liang Cao, Simon Laflamme, James Ricles, Spencer Quiel, Douglas Taylor

Civil, Construction and Environmental Engineering Publications

Cladding systems typically serve architectural purposes and protect occupants against the external environment. It is possible to leverage these systems to enhance structural resiliency. A common application is the use of blast resistant panels for enhanced protection against man-made hazards, whereas energy is dissipated through sacrificial elements. However, because these protection systems are passive, their mitigation capabilities are bandwidth limited, therefore targeting single types of hazards. The authors have recently proposed a novel variable friction cladding connection (VFCC), which enables the leveraging of cladding inertia for mitigating blast, wind, and seismic hazards. The variation in the friction force is generated ...

Download Bmp Trains 2020 Newest Version, Martin Wanielista

BMP Trains

BMP Trains 2020 is an improvement from all previous versions – most notably because of the departure from the Microsoft Excel platform to being programmed and compiled using the C++ programming language. The entire user interface and much of the internal function has been completely overhauled, while still preserving the essential goal of quantifying pre- and post-development average annual nutrient loadings (Nitrogen and Phosphorus) and determining the average annual effectiveness of a wide variety of Best Management Practices (BMPs) for the nutrients’ removal. The research by Dr. Harvey Harper, Dr. Marty Wanielista, Dr. Mike Hardin, Eric Livingston, and others in computing ...

Visualising The Complex Features Of Source Code, Ivan Bacher

Doctoral

Software development is a complex undertaking composed of several activities that include reading, writing, and modifying source code. Indeed, previous studies have shown that the majority of the effort invested in software development is dedicated to understanding code. This includes understanding the static structure, dynamic behaviour, and evolution of the code. Given these particular characteristics, as well as the high complexity of source code, it is reasonable to consider how visualisation can facilitate source code understanding. This work proposes to extend existing software development tools with visualisations that can be used to encode the various complex features within a source ...

Optimization Of Processing Parameters Of Nanocomposite Film For Fresh Sliced Okra Packaging, Adeshina Fadeyibi Phd, Zinash Delebo Osunde Phd, Professor, Mohammed Gana Yisa Professor

Journal of Applied Packaging Research

Nanocomposite film can be regarded as an active packaging material which is capable of curtailing microbial growth and keeping food for an extended life. In this research, the optimum processing parameters of cassava starch-zinc nanocomposite film was determined for packaging fresh-sliced okra. Samples of the films, with thickness ranging between 15– 17µm, were developed from the blends of 24g of cassava starch, 0–2 % zinc nanoparticles (NP) and 45–55 % glycerol in 600 ml distilled water. The ideal film was determined by optimizing the film processing parameters using Box-Behnken Design in Surface Response Methodology. It was subsequently used to package ...

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