Engineering Commons^™

A Novel Dataset-Similarity-Aware Approach For Evaluating Stability Of Software Metric Selection Techniques, Taghi M. Khoshgoftaar, Huanjing Wang, Randall Wald, Amri Napolitano

Computer Science Faculty Publications

Software metric (feature) selection is an important preprocessing step before building software defect prediction models. Although much research has been done analyzing the classification performance of feature selection methods, fewer works have focused on their stability (robustness). Stability is important because feature selection methods which reliably produce the same results despite changes to the data are more trustworthy. Of the papers studying stability, most either compare the features chosen from different random subsamples of the dataset or compare each random subsample with the original dataset. These either result in an unknown degree of overlap between the subsamples, or comparing datasets …

A Laboratory-Based Course In Real-Time Digital Signal Processing Using The Tms320c40, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

No abstract provided.

Commissioning Of The Asta Laser Lab With Uv Pulse Length Characterization, Daniel Kelley, Jeff Corbett

STAR Program Research Presentations

The Linac Coherent Light Source (LCLS) at SLAC depends on a photocathode electron gun to provide the linear accelerator with the raw material – electrons – used for making X-ray laser pulses. The photocathode used in the LCLS Injector is a clean copper plate in high vacuum. When the cathode is struck with high energy UV light, electrons are liberated from its surface and then accelerated down the linac with radio-frequency electric fields. These fast-moving bunches of electrons are directed through an undulator magnet to radiate X-ray light.

Although scientists have been using photocathode techniques at SLAC for 25 years, …

Two-Stage, High-Altitude Rocket With Internal Skeleton Design Entered In Advance Category Of 7th Esra Irec, Samuel S. Bowman, Kevin J. Byrne, Allen Capatina, Aliki S. Loper-Leddy, Joshua A. Van Schoyck

Aerospace Engineering

A high-altitude, two-stage rocket was designed, built, and entered in the advanced category of the 7^th Annual Experimental Sounding Rocket Association (ESRA) Intercollegiate Rocketry Engineering Competition (IREC). The rocket, called AJAKS, featured an internal skeleton made of carbon fiber rods, and a combination of plywood, carbon, and aluminum bulkheads. Loads were driven through the internal structure, with an outer skin tube providing an aerodynamic surface. A unique separation device was developed to ensure proper stage separation. The competition required the rocket to carry a 10-lb payload, which was chosen by the team to consist of an IMU and data …

Effects Of Sprinkler, Partial Sprinkler/Drip, And Drip Only Irrigation On Strawberry Transplants 2011-2012, Stuart Styles

BioResource and Agricultural Engineering

The Cal Poly Irrigation Training and Research Center (ITRC), in collaboration with academic, water district, and industry partners, proposes to evaluate new strategies for drip irrigation on strawberries to minimize runoff during transplant establishment.

The most common method used for irrigating strawberries is a mix of sprinkler irrigation and drip. Growers use sprinkler irrigation for bed preparation and salinity control, then eventually switch to drip irrigation after transplanting, but continue to use sprinkler irrigation as an insurance policy (for bonding between plant roots and soil bonding, washing off the leaves, controlling salinity, and frost). However, field observations have shown that …

Investigation Of Spillover Effect To Enhance Hydrogen Storage, Sarah C. Corrigan, Lin Simpson, Thomas Gennett

STAR Program Research Presentations

Hydrogen is an attractive energy option because of its low
environmental impact, but a critical problem is its low energy
density, which makes it difficult to store. For example, the US
Department of Energy (DOE) hydrogen plan for fuel cell powered
vehicles requires a gravimetric density of 6.5 wt%. There are several
existing hydrogen storage methods, including compressed gas,
liquefaction, metal hydrides, and physisorption, but at present, none
of these technologies comes close to achieving the targets set by the
DOE. Although chemical storage methods have been claimed to be the
most promising hydrogen storage technology, and activated carbons the …

Cad Vs. Sketching: An Exploratory Case Study, David Veisz, Essam Z. Namouz, Shraddha Joshi, Joshua D. Summers

All CEDAR Publications

This paper presents a preliminary comparison between the role of computer-aided design (CAD) and sketching in engineering through a case study of a senior design project and interviews with industry and academia. The design team consisted of four senior level mechanical engineering students each with less than 1 year of professional experience are observed while completing an industry sponsored mechanical engineering capstone design project across a 17 week semester. Factors investigated include what CAD tools are used, when in the design process they are implemented, the justification for their use from the students' perspectives, the actual knowledge gained from their …

Analyzing The Non-Functional Requirements In The Desharnais Dataset For Software Effort Estimation, Ali Bou Nassif, Luiz Fernando Capretz, Danny Ho

Electrical and Computer Engineering Publications

Studying the quality requirements (aka Non-Functional Requirements (NFR)) of a system is crucial in Requirements Engineering. Many software projects fail because of neglecting or failing to incorporate the NFR during the software life development cycle. This paper focuses on analyzing the importance of the quality requirements attributes in software effort estimation models based on the Desharnais dataset. The Desharnais dataset is a collection of eighty one software projects of twelve attributes developed by a Canadian software house. The analysis includes studying the influence of each of the quality requirements attributes, as well as the influence of all quality requirements attributes …

A Laboratory Study Of Levee Scour From Overtopping Storm Waves And Protection For Robust Desgins, Earnest Johnson

All Theses

Levee failure due to scouring has been a prominent occurrence among intense storm surges and waves, giving rise to the implementation of various scour protection measures over the years. Several experiments were performed on a model levee on either bare levee soil or with a scour protection measure covering the soil. The purpose of this study is to breakdown the dynamics of levee scour due to overtopping waves and suggest efficient methods in reducing the amount of scour. The levee soil was made up of a sand-clay mixture and placed in a laboratory wave tank that created a constant wave …

Risk Analysis And Reliability Improvement Of Mechanistic-Empirical Pavement Design, Xingqiang Danny Xiao

Graduate Theses and Dissertations

Reliability used in the Mechanistic Empirical Pavement Design Guide (MEPDG) is a congregated indicator defined as the probability that each of the key distress types and smoothness will be less than a selected critical level over the design period. For such a complex system as the MEPDG which does not have closed-form design equations, classic reliability methods are not applicable. A robust reliability analysis can rely on Monte Carlo Simulation (MCS). The ultimate goal of this study was to improve the reliability model of the MEPDG using surrogate modeling techniques and Monte Carlo simulation.

To achieve this goal, four tasks …

Effects Of Testing Time On Anaerobic Toxicity Assessment, Omolola Atinuke Akintomide

Graduate Theses and Dissertations

Anaerobic digestion has been widely used for wastewater treatment for decades. Several Anaerobic Toxicity tests have been developed to screen wastewater for toxicity and assess the treatability of such toxicants. However, past research and reviews on Biochemical Methane Potential (BMP) test and Anaerobic Toxicity Assay (ATA) were considered in this study.

The experimental tests included ammonium-nitrogen and sodium chloride toxicity tests with varied concentration and solid retention time. These tests were designed to demonstrate the impact of ammonia- nitrogen and sodium chloride on the biological degradation process. The anaerobic test set-up includes bench-scale test reactors and respirometers used for measuring …

Magnitude And Frequency Of Floods For Rural, Unregulated Streams Of Tennessee By L-Moments Method, Hongxiang Yan

Graduate Theses and Dissertations

This study presents a regional frequency analysis of Tennessee using the well-known Bulletin-17B method standardly used in the United States and the relatively new and developing L-Moments methods. Flood frequency characteristics were defined for 416 gaging stations located primarily in rural and lightly developed areas of Tennessee. All the gaging stations have 10 or more years of record through 2006. Using the L-Moments method, the generalized extreme value distribution was identified as the most robust distribution for each of four hydrologic areas. Multiple regression equations were also calculated for estimating the flood frequency of ungaged, unregulated, rural streams in each …

The Development Of A High Performance Concrete To Store Thermal Energy For Concentrating Solar Power Plants, Emerson Esmond John

Graduate Theses and Dissertations

In recent years, due to rising energy costs as well as an increased awareness of the environmental effects of greenhouse gas emissions produced through traditional forms of energy production, there is great interest in developing alternative sources of energy. One of the most viable alternative energy sources is solar energy. In particular, concentrating solar power (CSP) technologies have been identified as an option for meeting utility needs in the U.S. Southwest. These systems are required to produce electricity not only during periods of high solar radiation but also during times of reduced radiation due to cloud cover, and even extend …

Investigating The Bond Of Prestressing Strands In Lightweight Self-Consolidating Concrete, Royce Woodrow Floyd

Graduate Theses and Dissertations

Lightweight self-consolidating concrete (LWSCC) is a relatively recent advancement in concrete technology. The reduced dead load from lightweight concrete is beneficial for precast elements and for elements where dead load is a significant portion of the total load, such as prestressed bridge girders. Self-consolidating concrete (SCC) is a specially proportioned concrete mixture that consolidates under its own weight without the need for vibration. The combination of lightweight concrete and self-consolidating behavior provides the benefits of both. Bond of prestressing steel has been a much debated topic since the 1950s. Limited data are available on the transfer and development length of …

Improved Protocols For Automated Wheelpath Crack Detection In Pavements, Daniel Patrick Byram

Graduate Theses and Dissertations

Roadway pavement distress evaluations are vital to understanding the mechanics of pavement stability, determining the distribution of rehabilitation costs, and knowing the appropriate rehabilitation strategies. Advancements in technology over the past two decades have changed the way these surveys have been performed by means of automated data collection and interpretation. More and more state agencies have invested in automated road analyzing vehicles that are able to collect high resolution images of the pavement. Fewer have adopted automated data processing software with the ability to interpret road distresses due to the common discrepancies in distress classification algorithms.

In addition to automated …

New Insights Into Disinfection Byproduct Formation And Control: Assessing Dissolved Organic Matter Diffusivity And Chemical Functionality, Ashley Pifer

Graduate Theses and Dissertations

Methods were developed for application of asymmetric flow field-flow fractionation (AF4) and fluorescence parallel factor (PARAFAC) analysis to raw and treated samples from drinking water sources to improve characterizations of dissolved organic matter (DOM) and discover DOM properties correlated to disinfection byproduct (DBP) formation potential (FP). Raw water samples were collected from a reservoir, adjusted to pH 6, 7, and 8 and subjected to (1) jar tests using aluminum sulfate (alum) and (2) treatment with magnetic ion exchange (MIEX^®) resin. Both treatments were followed by DBPFP tests at pH 7. AF4 was used to size DOM in raw …

Wheel Path Wandering Based On Field Data, Wenting Luo

Graduate Theses and Dissertations

The position and width of wheel path on a pavement lane is an important consideration in conducting pavement distress survey, especially for distinguishing longitudinal cracking from fatigue cracking. Currently, the widely used wheel path definition is derived from the LTPP distress manual with fixed width and position, in which the influence of traffic wander on wheel path was overlooked. This thesis attempts to develop a new wheel path definition based on the lateral placement investigation of heavy vehicles' wandering in the field. Generally, the factors influencing vehicle lateral placement can be divided into seven categories, but only four factors are …

Fabrication And Characterization Of Biocomposites From Polylactic Acid And Bamboo Fibers, Sarah E. Royse

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Environmental concerns have been motivating research in the field of biodegradable materials, especially those from biological sources. Polylactic acid (PLA) is one biopolymer with the potential to replace some standard synthetic polymers. PLA is currently used for fibers, medical sutures, and some packaging, but is still used very little compared with synthetic polymers. One thing that can be done to expand the potential applications of PLA is to add fibers to create composite materials. Bamboo is a good choice for these fibers because it is abundant in many parts of the world, grows very quickly, and is widely unused. Composites …

A Model For Optimizing The Allocation Of Ethanol Production In The U.S., Anali Huggins

Department of Industrial and Management Systems Engineering: Dissertations, Theses, and Student Research

In the last five years, fuel prices have fluctuated from 2.86$/gallon to 3.87$/gallon which represents an increase of 35%. This situation has collocated the ethanol manufacturing in an advantageous situation. However, a major problem that is faced by the ethanol producers is the high cost of transportation. The objective of this thesis study is to determine the optimal allocation of ethanol production in the U.S. in 2009 that minimizes the transportation cost. This thesis is based on the application of a linear programing model. The thesis is focused on two questions. The first is the optimal allocation of ethanol between …

Magnetic Properties Study Of The Mn-Al System With Additions Of B Or C And Mechanical Milling Techniques, Timothy E. Prost

Department of Engineering Mechanics: Dissertations, Theses, and Student Research

Recently a shift in the focus of permanent magnetic research has moved from Rare Earth (RE)-based alloys to those made from more readily available elements. Because of their relatively large magnetocrystalline anisotropy, L1₀ compounds have the potential for use as permanent magnet materials. One particular alloy that is readily available and inexpensive is near equi-atomic manganese and aluminum (Mn₅₀-Al₅₀). First characterized in 1958, it did not receive much attention until more recently when RE supply chain issues made the alloy more attractive for commercial and research applications. The ferromagnetic (FM) τ-phase (L1₀) is …

Fabrication And Characterization Of Thermomechanically Processed Sulfur And Boron Doped Amorphous Carbon Films, Lonnie Carlson

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Small scale, high power density, reliable, and long-life power supplies would be useful or even critical for space missions or the growing number of microdetectors, microsensors, and miniature vehicles. Alpha or beta particle voltaic devices could satisfy these requirements but have been shown to degrade quickly due to radiation damage. Amorphous carbon (a-C) PN junctions or PIN devices could provide radiation hardness and sufficiently high efficiency. As the range of alpha and beta particles in a-C is ~20-120μm, much thicker films than are typical are needed to maximize collection of the particle energy.

In this work, the fabrication of thermomechanically …

Assessing Anaerobic Bio-Oxidation Of Vinyl Chloride And Ethene, Ademola Bakenne

All Theses

Perchloroethene (PCE) and trichloroethene (TCE) are two of the most commonly used chlorinated solvents around the world. These compounds and their dechlorination daughter products have become the most prevalent organic contaminants found in a majority of hazardous waste sites in the United States. Since implementation of traditional remediation methods would cost hundreds of billions of dollars, there has been tremendous interest in bioremediation as a low cost alternative to achieving remedial goals. Anaerobic reductive dechlorination is the most prevalent form of bioremediation in most locations. The ultimate daughter products from reductive dechlorination of PCE and TCE are ethene and ethane, …

Development Of A Ripple Rejection Controller For Dc Commutated Motors, Spencer M. Atkin

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The requirement of modern systems to be quiet and run smoothly increases production costs. The manufacture and purchase of high quality motors that meet these demands becomes increasingly costly. By using the ever increasing computer power available in micro-controllers, at the same costs, it is possible to use current sensing to develop control adjustments which decrease power ripples caused by the commutators of basic DC commutated motors. These ripples if left unmitigated propagate through to torque ripples which then increase the acoustic noise level present.

Load Sensor In An Elastomer Suspension Element, Jazmin Ley

Theses and Dissertations - UTB/UTPA

Knowledge of the loading applied to railcar suspension elements is necessary for improved rail safety, efficiency, and for monitoring bearing health. An economical, reliable system for keeping track of both dynamic and static loads on a rail car bearing offers potential for many improvements in rail service. The difficulties of implementing such a system are considerable because the sensor must be in the bearing load path and is thus subject to all the stressors of that environment including high impact, high load, high temperature, and corrosion. This thesis describes an attempt to incorporate a load measurement system in a polyurethane …

Auto-Fluorescence Lifetime And Light Reflectance Spectroscopy For Breast Cancer Diagnosis: Potential Tools For Intraoperative Margin Detection, Vikrant Sharma, Shivaranjani Shivalingaiah, Yan Peng, David Euhus, Zygmunt Gryczynski, Hanli Liu

Bioengineering Faculty Publications - Archive

This study investigates the use of two spectroscopic techniques, auto-fluorescence lifetime measurement (AFLM) and light reflectance spectroscopy (LRS), for detecting invasive ductal carcinoma (IDC) in human ex vivo breast specimens. AFLM used excitation at 447 nm with multiple emission wavelengths (532, 562, 632, and 644 nm), at which autofluorescence lifetimes and their weight factors were analyzed using a double exponent model. LRS measured reflectance spectra in the range of 500-840 nm and analyzed the spectral slopes empirically at several distinct spectral regions. Our preliminary results based on 93 measured locations (i.e., 34 IDC, 31 benign fibrous, 28 adipose) from 6 …

Optical Mode Study Of Galium Nitride Based Laser Diodes, Douglas Cattarusa

Electrical Engineering

This paper focuses on the optical mode analysis of laser diodes to improve light emission. Under the mode analysis, we compare the optical confinement factor (OCF) percentage of the emitting light from the LDs. There are two structures which we analyze: a basic GaN waveguide structure and an InGaN waveguide structure. The second structure has additional InGaN waveguides and is analyzed under two additional design variations: the concentration of Indium and the thickness of the top waveguide layer. The results of this study indicate introducing InGaN waveguide layers correlates with lower order modes (zero and first order) and increase the …

Absorber Geometry Optimization For A New Wave Energy Converter, Rachel A. Durren

Masters Theses

Alternative energy technologies are on the forefront of research due to the rising costs of oil and natural gas. One relatively under development source of energy is ocean waves. In order to make the use of ocean waves economically viable, the amount of energy absorbed by wave energy converters (WEC) must be optimized. The research within presents a new conceptual design, "Aqua Fly", for a WEC with emphasis on maximizing the amount of energy absorbed. The energy absorption component of the "Aqua Fly" was isolated and a small scale 2-D study of energy absorption. First, the amount of energy in …

Statistical And Numerical Integrated Approach For Detecting Onset Of Prefabricated Bridge Component Connection Deterioration, Cem Mansiz

Masters Theses

Bridges are the substantial part of the transportation infrastructure. Most recent report shows that of the 605,086 bridges in the United States, 67,526 (11%) are deemed structurally deficient, and 76,363 (13%) are declared functionally obsolete (FHWA, 2011). Deck is the shelter of a bridge that is subjected to severe loads due to exposure and traffic. Importance of detecting deck deterioration is further highlighted with the introduction of accelerated bridge construction (ABC) where prefabricated components are brought to the site, assembled, and connected using field cast joints. However, durability performance of field cast connections is not encouraging. Hence, continuous monitoring of …

The Reduction Of Glycerol Flow In A Porous Medium Through A Barrier Coating Application, Thomas Tran

Masters Theses

Coatings for paper are categorized into two groups: pigmented or functional. Functional coatings provide functionality in addition to the normal coating properties. Functional coatings can be used for friction control, release properties, abrasion resistance, and barrier properties. A coating that is designed to control barrier properties can be categorized into a sub-group of functional coatings called barrier coatings.

Barrier coatings can retard or eliminate the flow of fluids thru a coated substrate. The barrier can be effective in repelling or resisting the transmission rate of numerous fluids including moisture, oil, oxygen, grease, and glycerol. Barrier coatings have many useful applications …

The Effect Of Granular Activated Carbon Pretreatment And Sand Pretreatment On Microfiltration Of Greywater, David Christopher

All Theses

Around the world, water scarcity is driving people to practice water reuse. One form of water reuse is the recycling of greywater, which is household wastewater excluding toilet waste. With adequate treatment, greywater may be recycled onsite for applications that do not require potable water, such as irrigation or toilet flushing. Membrane filtration (including microfiltration (MF)) is one option for greywater treatment. The small footprint, modular nature, and predictable performance of MF make it an attractive option. However, direct MF of greywater can lead to rapid membrane fouling. This thesis investigated two possible pretreatments for reducing membrane fouling and improving …