Engineering Commons^™

Automated Device To Measure Slurry Properties In Drilled Shafts, Miles Patrick Mullins

USF Tampa Graduate Theses and Dissertations

Slurry is the fluid within a drilled excavation that is introduced when an excavation is deeper than the water table or where additional stability is needed for loose sandy dry soils. Although construction practices vary greatly throughout the country and the world, slurry levels should be maintained above the existing ground water level by a suitable margin. The most widely used slurry type is mineral slurry formed by mixing dry clay powder with water; either bentonite or attapulgite powder may be used (attapulgite being used in saline water conditions). Regardless of whether the slurry material is mineral, polymer or natural, …

Differential Association Of Vitronectin And Fibronectin With Glass And Electrospun Fibers Of A Poly (D-Lysine) /Poly (Acrylic Acid), Syed Muhammad Sohaib Zafar Zafar

USF Tampa Graduate Theses and Dissertations

Proteins represent major constituent of the extracellular matrix which plays an important role in the formation, maintenance and remodeling of tissues, this project focuses on adsorption of two specific serum proteins fibronectin (FN) and vitronectin (VTN) responsible for mediating cell matrix interaction through integrin binding, tripeptide Arg-Gly-Asp (RGD) sequence found in these protein features are recognized by αβV₃ integrin which ultimately helps in clot formation.

Flight Control And Hardware Design Of Multi-Rotor Systems, Nathan M. Zimmerman

Master's Theses (2009 -)

This thesis overviews crucial concepts involved in achieving quadcopter flight such as orientation estimation and control system implementation. This thesis also presents researchers with comprehensive hardware and software specifications for a quadcopter system. The primary application for this system would be for research with regards to the implementation of advance control techniques as well as data acquisition. Key constructs of this system include hardware software specifications for a flight controller, the radio system, and the sensorless brushless motor controllers. Firstly, the thesis starts by developing a reference frame and a mathematical model for the quadcotper system. Next, flight orientation estimation …

Examining Bridges Between Informal And Formal Learning Environments: A Sequential Mixed Method Design, Dagen L. Valentine

Department of Agricultural Leadership, Education, and Communication: Dissertations, Theses, and Student Research

The purpose of this sequential mixed method study was to identify schools implementing a technology-based engineering design intervention in a way that connects or bridges formal learning environments of the school-day to informal learning environments such as afterschool programs. Further, this study investigated educators’ decisions that enabled or facilitated bridging between formal and informal learning environments. This cooperation and/or linking between informal and formal learning time is bridging. Participants included public schools (n=16) in Eastern Nebraska that incorporated the Nebraska Wearables Technology (WearTec) program at their school, club or Out-of-School-Time program during the 2015-2016 school year. Three of the schools …

Impacts Of Water And Saline Brine Flow On Fractured Wellbore Cement, Joshua Robert Ellison

Civil Engineering ETDs

Fractures in wellbore cements can develop and provide pathways allowing fluids such as hydrocarbons or brines to communicate with freshwater aquifers and/or reach the surface. Once formed, these fractures can be altered by the stresses acting on them as well as reactions with the fluids moving through them. Previous studies, mostly with acidic brines flowing through a fracture, have shown dissolution/precipitation reactions cause permeability to decrease and mechanical properties to change as the acidic brine creates reaction fronts slowly propagate through the face of the fractures. This study investigated fractured cement reacted with de-ionized water and saline brine under varying …

Use Of Cycling Paths Along The Morogoro Brt Line, Ford Sanger

Independent Study Project (ISP) Collection

As the urban population continues to increase rapidly in Dar es Salaam it will become increasingly important to find sustainable means of urban transportation. With planned infrastructure improvements in the city to help alleviate traffic congestion, bicycles, which represent a largely underutilized form of urban transportation, have the potential to play a large role in the future of the city. Through background research, direct observations, community surveys, and interviews, both formal and informal, this study sought to understand the impact of the recent addition of bike lanes along the first phase of the Dar Bus Rapid Transit line. It was …

Characterization Of Consolidated Granular Salt, Melissa Marie Mills

Civil Engineering ETDs

Granular salt is likely to be used as backfill material and a seal system component within geologic salt formations serving as a repository for long-term isolation of nuclear waste. Pressure from closure of the surrounding salt formation will promote consolidation of granular salt, eventually resulting in properties comparable to native salt. Understanding the consolidation processes dependence on stress state, moisture availability, and temperature is important for demonstrating sealing functions and long-term repository performance. This study includes the characterization of laboratory-consolidated salt by means of microstructural observations, measurement of physical properties related to the pore structure, and quantification of pore sizes …

Experimental Modal Analysis And Seismic Mitigation Of Statue-Pedestal Systems, Christine E. Wittich, Tara C. Hutchinson

Department of Civil and Environmental Engineering: Faculty Publications

The seismic protection of cultural heritage, particularly statues, is a critical issue due to its high cultural significance, difficulty to repair or replace artifacts, and observed poor behavior during past earthquakes. Recent research has explored analysis techniques and methodologies for predicting the seismic response of statues; however, these studies typically assume the statue to be either freestanding or rigidly attached. The seismic response of statues with these different boundary conditions varies widely and therefore accurate characterization is critical. While modern mounting techniques aim to rigidly attach a statue to the floor or to a pedestal, the degree of rigidity of …

Fugitive Emissions, University Of North Dakota. Energy And Environmental Research Center

EERC Brochures and Fact Sheets

Fact sheet about fugitive emissions, their causes, and U.S. Environmental Protection Agency methods of detection and regulation. [This item is an outdated or superseded version and retained for historical purposes only. It may no longer reflect current information, policies, or practices.]

Computational Modeling Of Facial Response For Detecting Differential Traits In Autism Spectrum Disorders, Manar D. Samad

Electrical & Computer Engineering Theses & Dissertations

This dissertation proposes novel computational modeling and computer vision methods for the analysis and discovery of differential traits in subjects with Autism Spectrum Disorders (ASD) using video and three-dimensional (3D) images of face and facial expressions. ASD is a neurodevelopmental disorder that impairs an individual’s nonverbal communication skills. This work studies ASD from the pathophysiology of facial expressions which may manifest atypical responses in the face. State-of-the-art psychophysical studies mostly employ na¨ıve human raters to visually score atypical facial responses of individuals with ASD, which may be subjective, tedious, and error prone. A few quantitative studies use intrusive sensors on …

Microbubble Generation By Piezoelectric Transducers For Biomedical Studies, Mohammed Alkhazal

Electrical & Computer Engineering Theses & Dissertations

Bubbles induced by blast waves or shocks are speculated as the major cause of damage in biological cells in mild traumatic brain injuries (TBI). Microbubble collapse was found to induce noticeable cell detachment from the cell substrate, changes in focal adhesion, and biomechanics. To better understand the bubble mechanism, a system needs to be constructed which allows clear differentiation on the impact of bubbles from that of shocks. Such a generator needs to be low profile in order to place under a microscope. A piezoelectric transducer system was designed to meet the need. The system uses either a flat or …

Constrained-Energy Cross-Well Actuation Of Bistable Structures, Masoud Zarepoor

Mechanical & Aerospace Engineering Theses & Dissertations

Bistable structures have two stable equilibrium positions and can be utilized to maintain a specific static shape with no energy consumption. This dissertation focuses on the minimum required energy for performing snap-through of a bistable structure. Snap-through is the motion of a bistable structure from one stable equilibrium position to the other. This research uses the Duffing-Holmes equation as a one-degree-of-freedom representative model of a bistable structure, and this nonlinear equation is solved to calculate the required energy for cross-well oscillation. The research identifies several unique features of the response of a bistable system subjected to force and energy constraints. …

Detecting And Resolving Air Traffic Conflicts Using A Point Of Closest Approach Method, Marc S. Easton

Mechanical & Aerospace Engineering Theses & Dissertations

A geometrical point of closest approach method is used to solve air traffic conflict detection/resolution problems with a single conflict vehicle that is unaware or unable to aid in resolving the conflict. Nonlinear, three degree of freedom equations of motion for a point-mass vehicle are derived and formulated to allow commanded trajectories to steer the vehicle to a desired location. A dynamic model is developed to propagate the vehicle in three dimensions. A closed-loop model implementing a negative feedback controller using a Proportional-Integral-Derivative control scheme is used to drive the vehicle to match the commanded trajectories. A conflict detection/resolution algorithm …

Global Sensitivity Analysis Of Mat Foundation Behavior By Using Finite Element Modeling, Yang Zhao

Civil & Environmental Engineering Theses & Dissertations

Mat foundation is used mostly for high-rise buildings and, since the demand for high- rise buildings is growing, having extensive understanding of mat foundation behavior leads us into more efficient structural design. Mat foundation behaviors are affected mostly by soil’s materials properties, foundation size, and thickness and loading conditions. In this study, the sensitivity of mat foundation structural responses to some of the design parameters are evaluated. Sobol decomposition, which is a variance-based technique, is used to perform the global sensitivity analysis. In this study, Patran, a finite element-based software, is used for modeling and simulations.

Approximate flexible method is …

Methodologies For Estimating Traffic Flow On Freeways Using Probe Vehicle Trajectory Data, Khairul Azfi Anuar

Civil & Environmental Engineering Theses & Dissertations

Probe vehicle data are increasingly becoming the primary source of traffic data. As probe vehicle data become more widespread, it is imperative that methods are developed so that traffic state estimators such as flow, density, and speed can be derived from such data. In this dissertation three different methodologies are proposed for predicting traffic flow or volume on a freeway. All of the proposed methodologies exploit several different traffic flow theories in conjunction with probe vehicle data to predict traffic flow. The first methodology takes advantage of the fundamental diagram or speed-flow relationship. The relationship states that flow can be …

Passenger Obesity And Regional Aircraft Performance For The Most Corpulent States In The Usa, Douglas D. Boyd

Publications

Obesity affects over 25% of Americans; however, prescribed FAA standard passenger weights for US airlines are based on data compiled 15 years ago. Since increased passenger weight degrades aircraft performance and may lead to a loss of control, the hypothesis herein is that passenger weight under-estimation for states with high obesity rates could potentially lead to a runway overrun or the inability to out climb rising terrain. In terms of the employed methodology, current person weights for the ten most obese states were determined using nationwide data adjusted for state ethnicity. Performance degradation for regional aircraft was assessed by accelerate-stop …

Hydrothermal Synthesis And Characterisation Of Bioactive Glass-Ceramic Nanorods, Ehsan Zeimaran, Sara Pourshahrestani, Seyed Farid Seyed Shirazi, Belinda Pingguan-Murphy, Nahrizul Adib Kadri, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

In this study fabrication of rod-like bioactive glass-ceramics (BGCs) using hydrothermal treatment based on a sol-gel precursor is reported for the first time. BGCs with composition 58 wt% SiO₂, 33 wt% CaO and 9 wt% P₂O₅ were synthesized in different thermal conditions (200 and 220 °C) and characterised with regard to morphology, chemical composition and crystallinity. The bioactivity of the materials was assessed by immersion in simulated body fluid for up to 7 days. The results revealed that as the reaction temperature increased from 200 to 220 °C, the diameter of rods was reduced from …

Bioaugmentation And Correlating Anaerobic Digester Microbial Community To Process Function, Kaushik Venkiteshwaran

Dissertations (1934 -)

This dissertation describes two research projects on anaerobic digestion (AD) that investigated the relationship between microbial community structure and digester function. Both archaeal and bacterial communities were characterized using high-throughput (Illumina) sequencing technology with universal 16S rRNA gene primers. In the first project, bioaugmentation using a methanogenic, aerotolerant propionate enrichment culture was investigated as a possible method to increase digester methane production. Nine anaerobic digesters, seeded with different biomass, were operated identically and their quasi steady state function was compared. Before bioaugmentation, different seed biomass resulted in different quasi steady state function, with digesters clustering into high, medium or low …

Design Optimization Of Permanent Magnet Machines Over A Target Operating Cycle Using Computationally Efficient Techniques, Alireza Fatemi

Dissertations (1934 -)

The common practices of large-scale finite element (FE) model-based design optimization of permanent magnet synchronous machines (PMSMs) oftentimes aim at improving the machine performance at the rated operating conditions, thus overlooking the performance treatment over the entire range of operation in the constant torque and extended speed regions. This is mainly due to the computational complexities associated with several aspects of such large-scale design optimization problems, including the FE-based modeling techniques, large number of load operating points for load-cycle evaluation of the design candidates, and large number of function evaluations required for identification of the globally optimal design solutions. In …

"It's Such A Battle": A Phenomenological Account Of Raising A Child On The Autistic Spectrum - A Battle With Bureaucracy And Behaviour, Tara Vassallo

The Plymouth Student Scientist

A sharp rise in the prevalence of Autism Spectrum Disorder (ASD), has led to it becoming one of the most widely researched neurodevelopmental conditions. Although the predominant focus in autism research is child centred, research on parent outcomes has highlighted considerable impact, in terms of parent’s mental health and wellbeing. Previous studies have shown that parents of children with autism suffer extremes of distress, in excess of that of parents of children with other disabilities. However, why this is so is less understood. Interpretative phenomenological analysis was used to analyse data, gathered from semi-structured interviews of seven parents raising children …

Bs News July/August

Building Services Engineering

No abstract provided.

Carbon Deposition During Oxygen Production Using High Temperature Electrolysis And Mitigation Methods, Timothy Adam Bernadowski

Mechanical & Aerospace Engineering Theses & Dissertations

Carbon dioxide in the Martian atmosphere can be converted to oxygen during high temperature electrolysis for use in life-support and fuel systems on manned missions to the red planet. During electrolysis of carbon dioxide to produce oxygen, carbon can deposit on the electrolysis cell resulting in lower efficiency and possibly cell damage. This would be detrimental, especially when the oxygen product is used as the key element of a space life support system. In this thesis, a theoretical model was developed to predict hazardous carbon deposition conditions under various operating conditions within the Martian atmosphere. The model can be used …

Design Of Experiments Enhanced Statistical Process Control For Wind Tunnel Check Standard Testing, Ben D. Phillips

Mechanical & Aerospace Engineering Theses & Dissertations

The current wind tunnel check standard testing program at NASA Langley Research Center is focused on increasing data quality, uncertainty quantification and overall control and improvement of wind tunnel measurement processes. The statistical process control (SPC) methodology employed in the check standard testing program allows for the tracking of variations in measurements over time as well as an overall assessment of facility health. While the SPC approach can and does provide researchers with valuable information, it has certain limitations in the areas of process improvement and uncertainty quantification. It is thought by utilizing design of experiments methodology in conjunction with …

Extension Of The Gravity Model: A Risk Integrated Approach Towards The Impact Analysis Of Mega Sports Events On Inbound Tourist Arrivals, Abdul Sami Stanekzai

Engineering Management & Systems Engineering Theses & Dissertations

Mega sports events such as the Olympics and the FIFA World Cup are highly attended and countries compete ferociously to host such events due to their perceived long term positive effects. Inbound tourist forecasting is an important aspect of the hosting decision both for the organizing committees and the hosting nations. As a precaution against letting the event fall into incapable hands, which can lead into chaos and mismanagement, measures needs to be taken. Capacity evaluation of interested parties is possible, only by knowing the number of people who may attend the event. However, due to the infrequent occurrence of …

A Hybrid Tabu/Scatter Search Algorithm For Simulation-Based Optimization Of Multi-Objective Runway Operations Scheduling, Bulent Soykan

Engineering Management & Systems Engineering Theses & Dissertations

As air traffic continues to increase, air traffic flow management is becoming more challenging to effectively and efficiently utilize airport capacity without compromising safety, environmental and economic requirements. Since runways are often the primary limiting factor in airport capacity, runway operations scheduling emerge as an important problem to be solved to alleviate flight delays and air traffic congestion while reducing unnecessary fuel consumption and negative environmental impacts. However, even a moderately sized real-life runway operations scheduling problem tends to be too complex to be solved by analytical methods, where all mathematical models for this problem belong to the complexity class …

Robust And Resilient Control Design And Performance Analysis For Uncertain Systems With Finite Energy Disturbances, Fan Feng

Dissertations (1934 -)

This dissertation addresses the problem of robust and resilient control design with additional performance analysis for uncertain systems with finite energy disturbances. The control design is robust and resilient in the sense of maintaining certain performance criteria in the presence of perturbations in both system parameters and feedback gains. The performance analysis evaluates resilience properties of state feedback and dynamic (state estimate) feedback controllers. A resilient and robust state feedback controller is designed using linear matrix inequality (LMI) techniques for the characterization of solutions to the analysis and design problems posed in this work. Uncertainties are allowed in the linear …

Predicting Multiple Target Tracking Performance For Applications On Video Sequences, Juan Esteban Tapiero Bernal

Dissertations (1934 -)

This dissertation presents a framework to predict the performance of multiple target tracking (MTT) techniques. The framework is based on the mathematical descriptors of point processes, the probability generating functional (p.g.fl). It is shown that conceptually the p.g.fls of MTT techniques can be interpreted as a transform that can be marginalized to an expression that encodes all the information regarding the likelihood model as well as the underlying assumptions present in a given tracking technique. In order to use this approach for tracker performance prediction in video sequences, a framework that combines video quality assessment concepts and the marginalized transform …

Automated Code Extraction From Packed Android Applications., Abhishek Vasisht Bhaskar

Dissertations - ALL

Software packing is a method employed by malicious applications to hide their original intent. Extracting the original intent of an application from its application bundle, whether to perform a security analysis on it, to search for security flaws(or bugs) or simply for educational purposes is a key requirement for the security community. With the fluidity provided by the Android app store coupled with a complete application-framework based environment for a malicious user to employ as an attack space, it is of great importance to examine Android applications and extract their intent.

For basic applications, simple reverse engineering tools can be …

Engineering Xylose Utilization In Yarrowia Lipolytica By Understanding Its Cryptic Xylose Pathway, Gabriel M. Rodriguez, Murtaza Shabbir Hussain, Lauren Gambill, Difeng Gao, Allison Yaguchi, Mark Blenner

Publications

Background

The oleaginous yeast, Yarrowia lipolytica, has been utilized as an industrial host for about 60 years for various applications. Recently, the metabolic engineering of this host has become increasingly popular due to its ability to accumulate lipids as well as improvements made toward developing new genetic tools. Y. lipolytica can robustly metabolize glucose, glycerol, and even different lipid classes. However, little is known about its xylose metabolizing capability. Given the desirability of having a robust xylose utilizing strain of Y. lipolytica, we performed a comprehensive investigation and elucidation of the existing components of its xylose metabolic pathway. …

High-Throughput Screening Of Clinically Approved Drugs That Prime Polyethylenimine Transfection Reveals Modulation Of Mitochondria Dysfunction Response Improves Gene Transfer Efficiencies, Albert Nguyen, Jared P. Beyersdorf, Jean-Jack Riethoven, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Nonviral gene delivery methods are advantageous over viral vectors in terms of safety, cost, and flexibility in design and application, but suffer from lower gene transfer efficiency. In addition to modifications to nucleic acid design and nonviral carriers, new tools are sought to enhance transfection. Priming is the pharmacological modulation of transfection efficiency and transgene expression, and has demonstrated transfection increase in several compounds, for example, chloroquine and glucocorticoids. To develop a library of transfection priming compounds, a highthroughput screen was performed of the NIH Clinical Collection (NCC) to identify clinical compounds that prime polyethylenimine (PEI) transfection. HEK293T cells were …