Engineering Commons^™

Distributed Knowledge Discovery For Diverse Data, Hossein Hamooni

Computer Science ETDs

In the era of new technologies, computer scientists deal with massive data of size hundreds of terabytes. Smart cities, social networks, health care systems, large sensor networks, etc. are constantly generating new data. It is non-trivial to extract knowledge from big datasets because traditional data mining algorithms run impractically on such big datasets. However, distributed systems have come to aid this problem while introducing new challenges in designing scalable algorithms. The transition from traditional algorithms to the ones that can be run on a distributed platform should be done carefully. Researchers should design the modern distributed algorithms based on the …

Ion Size Effects On The Properties Of Charge Regulating Electric Double Layers, Divya Jyoti Prakash

Nanoscience and Microsystems ETDs

The behavior of charged interfaces formed in various systems like colloidal solution, fuel cells, battery, electro-deposition, catalysis is governed by the properties of electrical double layer(EDL). Civilized model with charge regulation boundary condition determined by thermodynamic equilibrium at the interface has been used to model electrical double layer and shows that size of the solvent plays a critical role in characterizing the properties of EDL using classical density functional theory.This thesis investigates the impact of ion size in electrolyte solutions on the electrical double layer formed at the interface using a similar model. It is found that ion size greatly …

Identification Of Developmental Stage And Anatomical Fraction Contributions To Cell Wall Recalcitrance In Switchgrass, Jacob D. Crowe, Nicholas Feringa, Sivakumar Pattathil, Brian Merritt, Cliff Foster, Dayna Dines, Rebecca Ong, David B. Hodge

Department of Chemical Engineering Publications

Background

Heterogeneity within herbaceous biomass can present important challenges for processing feedstocks to cellulosic biofuels. Alterations to cell wall composition and organization during plant growth represent major contributions to heterogeneity within a single species or cultivar. To address this challenge, the focus of this study was to characterize the relationship between composition and properties of the plant cell wall and cell wall response to deconstruction by NaOH pretreatment and enzymatic hydrolysis for anatomical fractions (stem internodes, leaf sheaths, and leaf blades) within switchgrass at various tissue maturities as assessed by differing internode.

Results

Substantial differences in both cell wall composition …

A Thermodynamic Study Of Binary Real Gas Mixtures Undergoing Normal Shocks, Josiah M. Bigelow

Mechanical Engineering ETDs

We investigate the difference between Amagat and Dalton mixing laws for gaseous equations of state (EOS) using planar traveling shocks. Numerical modeling was performed in the Sandia National Laboratories hydrocode CTH utilizing tabular EOS in the SESAME format. Numerical results were compared to experimental work from the University of New Mexico Shock Tube Laboratory. Latin hypercube samples were used to assess model sensitivities to Amagat and Dalton EOS. We find that the Amagat mixing law agrees best with the experimental results and that significant difference exist between the predictions of the Amagat and Dalton mixing methods.

Development Of Epitaxial Strategies Towards The Growth Of Novel Semiconductor Saturable Absorber Mirrors (Sesams) For Passively Mode-Locked Optically Pumped Vertical-External-Cavity Surface-Emitting Lasers (Vecsels), Sadhvikas J. Addamane

Electrical and Computer Engineering ETDs

Mode-locked VECSEL systems using SESAMs are a relatively less complex and cost-effective alternative to state-of-the-art ultrafast lasers based on solid-state or fiber lasers. This system has seen considerable progress in device performance in terms of pulse width and peak power in the recent years. However, these device characteristics still have to be improved greatly and this system has to become more reliable to become commercially relevant. The realization of femtosecond pulses over long periods of time is non-trivial due to the high sensitivity of SESAM characteristics to minor drifts in growth or cavity conditions. This work focuses on developing novel …

The Fate Of Fecal Indicator Bacteria In Passive Nitrogen Reduction Systems, Michelle B. Henderson

USF Tampa Graduate Theses and Dissertations

The sustainability of water resources is an international and national concern. With increased human activity, water distribution on a global, regional, and local scale has been negatively impacted. Managing water resources also includes managing wastewater. A promising solution to the issues of water scarcity and distribution in the environment is the reuse of wastewater. Wastewater is produced from various sources (domestic, industrial, and commercial); however, if this water is able to be reused closer to the source of generation it could positively impact water distribution. In the United States, approximately 25% of domestic wastewater is treated in onsite wastewater treatment …

Copper Electrodeposition In Mesoscale Through-Silicon-Vias, Lyle Alexander Menk

Nanoscience and Microsystems ETDs

Copper (Cu) electrodeposition (ECD) in through-silicon-vias (TSVs) is an essential technique required for high-density 3-D integration of complex semiconductor devices. The importance of Cu ECD in damascene interconnects has led to a natural development towards copper electrodeposition in TSVs. Cu ECD is preferred over alternative approaches like the chemical vapor deposition (CVD) of tungsten (W) or aluminum (Al) because Cu ECD films have lower film stress, lower processing temperatures, and more optimal thermal and electrical properties as compared with CVD W or Al.

Via filling with electroplated Cu on substrates that have undergone atomic layer deposition of a conformal platinum …

Graphite And Graphene-Oxide Based Pgm-Free Model Catalysts For The Oxygen Reduction Reaction, Joseph Henry Dumont

Nanoscience and Microsystems ETDs

The world currently relies heavily on fossil fuels such as coal, oil, and natural gas for its energy. Fossil fuels are non-renewable, that is, they draw on finite resources that will eventually dwindle, becoming too expensive or too environmentally damaging to retrieve. One alternative source of energy are fuel cells, electrochemical devices that convert chemical energy to cleanly and efficiently produce electricity. They can be used in a wide range of applications, including transportation, stationary, portable and emergency power sources. Their development has been slowed by the high cost of PGM electrocatalysts needed at both electrodes as well as sluggish …

Singularity Formation In The Geometry Of Perturbed Shocks Of General Mach Number, Wouter Mostert, Dale I. Pullin, Ravi Samtaney, Vincent Wheatley

Mechanical and Aerospace Engineering Faculty Research & Creative Works

While planar shock waves are known to be stable to small perturbations in the sense that the perturbation amplitude decays over time, it has also been suggested that plane propagating shocks can develop singularities in some derivative of their geometry (Whitham (1974) Linear and nonlinear waves. Wiley, New York) in a nonlinear, wave reinforcement process. We present a spectral-based analysis of the equations of geometrical shock dynamics that predicts the time to singularity formation in the profile of an initially perturbed planar shock for general shock Mach number. We find that following an initially sinusoidal perturbation, the shock shape remains …

Custom 3d Printer And Resin For 18 Μm × 20 Μm Mi- Crofluidic Flow Channels, Hua Gong, Bryce P. Bickham, Adam T. Woolley, Gregory P. Nordin

Faculty Publications

While there is great interest in 3D printing for microfluidic device fabrication, to-date the achieved feature sizes have not been in the truly microfluidic regime (μm). In this paper we demonstrate that a custom Digital Light Processor stereolithographic (DLP-SLA) 3D printer and a specifically-designed, low cost, custom resin can readily achieve flow channel cross sections as small as 18 μm × 20 μm. Our 3D printer has a projected image plane resolution of 7.6 μm and uses a 385 nm LED, which dramatically increases the available selection of UV absorbers for resin formulation compared to 3D printers with 405 nm …

Examination Of The Impact Of Condensed Biofeedback Training On Acute Stress Responses, Meredith Carroll, Brent Winslow

Aeronautics Faculty Publications

The objective of this study was to measure the effects of a condensed 90 minute Biofeedback Training (BFT) method on stress response and decision making performance under stress. Forty one novice male participants received either BFT training, which incorporated diaphragmatic breathing with Stress Inoculation Training (SIT), or a control training task. Participants completed pre- and post-training assessments which incorporated a socio evaluative stress induction method followed immediately by performance of a simulation- based decision making under stress scenario. Stress was assessed using real-time physiological measures of the Autonomic Nervous System (ANS) response and cortisol measures of the Hypothalamic-Pituitary-Adrenal (HPA) axis …

Examination Of Color Center Formation In Caf2 Crystals When Exposed To Gamma And Mixed Neutron/Gamma Fields, Sara M. Pelka

Nuclear Engineering ETDs

Color centers in CaF₂ were studied in this work, in parallel with examinations of changes in the refractive index of the crystals by the larger research group, after they were subjected to radiation. Color centers induced by gamma rays and in mixed neutron-gamma fields were studied in CaF₂ and LiF using transmittance and absorbance spectra. The goals were to examine both neutron and neutron-gamma mixed field irradiations to be able to isolate neutron only effects and to correlate these color center effects with refractive index effects studied by our larger collaboration. Irradiation sources include ¹³⁷Cs, DD and …

A New Fiber Reinforced Polymer Composite For Infrastructure Applications Using Recycled Carbon Fibers, Mojgan Maadandar

Civil Engineering ETDs

Abstract

Carbon fiber reinforced polymer (CFRP) composites have been attractive materials for many civil and mechanical applications. However, the high cost of carbon fibers has hindered its wide spread in many civil and structural applications. Furthermore, CFRP composites have been mostly disposed of in landfills after their end of service life, creating environmental concerns and potential release of toxic byproducts. A significant interest in recycling composites has appeared in the last decade for obtaining recycled carbon fiber. A process based on wet chemical degradation and thermal treatments of FRP composites showed the ability to produce recycled carbon fibers with 99% …

Waveguide-Coupled Avalanche Photodiodes For A Cmos Compatible Tranceiver Package, Nick Martinez

Nanoscience and Microsystems ETDs

Optical signal detection is most readily done with classical sources emitting signals

which undergo very little attenuation. Detection of signals with these power levels

benets from classical photodetectors, where the photon induced electronic signal is

discernible above the background noise. In other instances, where the optical signal

may start from an attenuated source, or in cases where the optical signal is severely

attenuated in transit, a detector which exhibits gain converts a weak optical signal

into a measurable electrical one. Detectors which convert a weak photo-generated

electrical pulse into a strong one do so through a process known as carrier …

Incorporating Census Data Into A Geospatial Student Database, Edwin Agbenyega

Electrical and Computer Engineering ETDs

The University of New Mexico(UNM) stores data on students, faculty, and staff at the University. The data is used to generate reports and fill surveys for several local, statewide and nationwide reporting entities. The reports convey statistical and analytical information such as the graduation rates, retention, performance, ethnicity, age, and gender of students. Furthermore, the Institute of Design and Innovation (IDI), and the Office of Institutional Analytics (OIA) at UNM use the data provided for various predictive studies aimed at improving student outcomes.

This thesis proposes geospatial data as an additional layer of information for the data repository. The paper …

Voices: Conference On Teaching Stem With Music, September 27-28, 2017, Gregory J. Crowther

Journal of Humanistic Mathematics

This first-of-its-kind, online-only conference will explore the use of music to teach STEM (science, technology, engineering, and mathematics) at the college level (including AP courses). Presentations will be live-streamed from the conference website, https://www.causeweb.org/voices. Online registrations (for only $10 apiece!) will be accepted at the conference website until the conclusion of the conference on September 28, 2017.

Performance Study On Evacuated Tubular Collector Coupled Solar Still In West Texas Climate, Roy Issa, Byungik Chang

Civil Engineering Faculty Publications

Experimental study was performed on a single basin active solar distillation system augmented with a solar collector using evacuated solar tubes. Field tests were conducted over several days under the climatic conditions of West Texas to evaluate the effect evacuated solar tubes have on the daily distillate yield rate. To investigate the feasibility of the solar tubes, active and passive solar stills with and without exterior insulation were examined. The maximum daily production rate for the active distillation system using evacuated solar tubes and the passive distillation system was 3.6 and 1.4 kg/m²day, respectively. The results showed the …

Role Of Vapor Phase Processes On The Sintering Of Diesel Oxidation Catalysts, Cristhian Carrillo

Nanoscience and Microsystems ETDs

This work provides a fundamental understanding on the vapor phase processes that govern the sintering of supported nanoparticles in relation to the diesel oxidation catalyst (DOC). Sintering is a deactivation process that affects this catalyst significantly, and many other catalyst systems. Therefore, it is important to understand the sintering mechanisms in order to improve the long term catalytic reactivity.

Pt is an active catalyst in the DOC but it sinters via Ostwald ripening to form large particles under the accelerated aging conditions (800 ^oC) recommended by the Department of Energy (DOE). At 800 ^oC in the presence of …

Bringing Space To The Classroom Through Stem Education Providing Extreme Low Earth Orbit Missions Using Thinsats, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

An article written by Bob Twiggs and associates titled "Bringing Space to the Classroom Through STEM Education Providing Extreme Low Earth Orbit Missions Using ThinSats" from July 10, 2017.

Novel Durable Antimicrobial Ceramic With Embedded Copper Sub-Microparticles For A Steady-State Release Of Copper Ions, Adam J. Drelich, Jessie Miller, Robert Donofrio, Jaroslaw Drelich

Michigan Tech Publications, Part 1

Using pottery clay, porous ceramic stones were molded and then decorated with copper sub-microparticles inside the pores. Copper added antimicrobial functionality to the clay-based ceramic and showed ability in disinfecting water. Populations of both Staphylococcus aureus and Klebsiella pneumoniae in contaminated water were reduced by >99.9% in 3 h when exposed to an antimicrobial stone. This antimicrobial performance is attributed to a slow release of copper into water at both room and elevated temperatures. Copper is leached by water to produce ion concentrations in water at a level of 0.05–0.20 ppm after 24 to 72 h immersion tests. This concentration …

Investigation Of Mimo Channel Characteristics In A Twosection Tunnel At 1.4725 Ghz, Rongchen Sun, David W. Matolak, Cheng Tao, Liu Liu, Zhenhui Tan, Tao Zhou

Faculty Publications

This paper presents results from a wide band single-input–single-output (SISO) and 16 16 virtual multiple-input–multiple-output (MIMO) measurement campaign at a center frequency of 1.4725 GHz in a 100-meter long tunnel laboratory which is terminated by a vertical wall with a metallic door. The path loss, root-mean-square delay spread (RMS-DS) characteristics, and power delay profiles (PDPs) are described. In addition, we provide results for the MIMO channel amplitude matrix, which offers a new perspective in understanding MIMO characteristics in tunnel scenarios. Our measurement results are analyzed and compared to ray tracing simulations. The relationships among the angle spread, channel matrix singular …

Design And Experimental Investigation Of 500kv Current Transformer Seismic Retrofit Utilizing Structure Rocking And Supplemental Damping With Self-Centering, Ilya S. Palnikov

Dissertations and Theses

Electrical substations perform a key role in electrical transmission and distribution; the ability for a substation to remain functional during and after a seismic event contributes significantly to the resilience of the clients supplied. Many legacy components currently installed in the main grid substations were designed with minimal consideration of lateral loads and are not qualified per IEEE693. One of the more critical high-voltage substation components that are vulnerable to earthquake damage is the 500kV freestanding current transformer (CT). The CT is particularly vulnerable due to the slenderness and mass distribution of the component. Current transformers are typically constructed from …

Statistical Topological Approach Using Wave-Chaos For Electromagnetic Effects (Stuwee), Ghadeh M. Hadi

Electrical and Computer Engineering ETDs

Predicting the nature of the scattering of short wavelength waves in random interconnected networks of large complicated enclosures is routinely encountered in diverse fields such as acoustics, wireless communications, and electromagnetic compatibility engineering. The Random Coupling Model (RCM), based on wave-chaos, is a statistical model describing the scattering of short wavelength electromagnetic waves in large complicated (chaotic) enclosures. The Baum-Liu-Tesche (BLT) electromagnetic topology formulation is a hierarchical framework based on the multiconductor transmission line (MTL) model for describing the flow of energy between different nodes on a network of MTL segments, originally developed to study the coupling of electromagnetic waves …

Uhf Rfid Antenna Impedance Matching Techniques, Kamron Sockolov, Dean Arakaki

Electrical Engineering

The modified T-match network uses planar inductive strips for conjugate matching Radio Frequency Identification (RFID) Integrated Circuits (RFICs). Narrow and broadband matching techniques and electromagnetic simulations are applied in [1] for specific designs. This paper extends these efforts through antenna element parameterization and design trade-off analysis. Narrow and broadband designs are fabricated; antenna input impedance and tag range tests confirm predictions.

Students Are The Engine Of Swbec | Sustainable Waste-To-Bioproducts Engineering Center, Usu College Of Engineering

College of Engineering News

More than 10 projects for 2017 include 20 students total with 6 graduate students and 14 undergraduate students.

Maximizing Operating Room Performance Using Portfolio Selection, Vivek Reddy Gunna, Amin Abedini, Wei Li

Mechanical Engineering Faculty Publications

The operating room (OR) is responsible for most hospital admissions and is one of the most cost and work intensive areas in the hospital. From recent trends, we observe an ironic parallel increase among expenditure and waiting time. Therefore, improving OR scheduling has become obligatory, particularly in terms of patient flow and benefit. Most of the hospitals rely on average patient arrivals and processing times in OR planning. But in practice, variations in arrivals and processing times causes high instability in OR performance. Our model of optimization provides OR schedules maximizing patient flow and benefit at a fixed level of …

An Optimization Model For Operating Room Scheduling To Reduce Blocking Across The Perioperative Process, Amin Abedini, Wei Li, Honghan Ye

Mechanical Engineering Faculty Publications

Operating room (OR) scheduling is important. Because of increasing demand for surgical services, hospitals must provide high quality care more efficiently with limited resources. When constructing the OR schedule, it is necessary to consider the availability of downstream resources, such as intensive care unit (ICU) and post anaesthesia care unit (PACU). The unavailability of downstream resources causes blockings between every two consecutive stages. In this paper we address the master surgical schedule (MSS) problem in order to minimize blockings between two consecutive stages. First, we present a blocking minimization (BM) model for the MSS by using integer programming, based on …

Effect Of Austempering Time On The Microstructure And Carbon Partitioning Of Ultrahigh Strength Steel 56nicrmov7, Quanshun Luo, Matthew Kitchen, Shahriar Abubakri

Henry M. Rowan College of Engineering Departmental Research

Ultrahigh strength steel 56NiCrMoV7 was austempered at 270 °C for different durations in order to investigate the microstructure evolution, carbon partitioning behaviour and hardness property. Detailed microstructure has been characterised using optical microscopy and field emission gun scanning electron microscopy. A newly developed X-ray diffraction method has been employed to dissolve the bainitic/martensitic ferrite phase as two sub-phases of different tetragonal ratios, which provides quantitative analyses of the carbon partitioning between the resultant ferrites and the retained austenite. The results show that, a short-term austempering treatment was in the incubation period of the bainite transformation, which resulted in maximum hardness …

Meniscus-Assisted Solution Printing Of Largegrained Perovskite Films For High-Efficiency Solar Cells, Ming He, Bo Li, Xun Cui, Beibei Jiang, Yanjie He, Yihuang Chen, Daniel O'Neil, Paul Szymanski, Mostafa A. El-Sayed, Jinsong Huang, Zhiqun Lin

Department of Mechanical and Materials Engineering: Faculty Publications

Control over morphology and crystallinity of metal halide perovskite films is of key importance to enable high-performance optoelectronics. However, this remains particularly challenging for solution-printed devices due to the complex crystallization kinetics of semiconductor materials within dynamic flow of inks. Here we report a simple yet effective meniscus-assisted solution printing (MASP) strategy to yield large-grained dense perovskite film with good crystallization and preferred orientation. Intriguingly, the outward convective flow triggered by fast solvent evaporation at the edge of the meniscus ink imparts the transport of perovskite solutes, thus facilitating the growth of micrometre-scale perovskite grains. The growth kinetics of perovskite …

A Multiscale Modeling Study Of The Mammary Gland, Joseph D. Butner

Biomedical Engineering ETDs

Multiscale, hybrid computer modeling has emerged as a valuable tool in the fields of computational systems biology and mathematical oncology. In this work, we present an overview of the motivations for, and development and implementation of, three hybrid multiscale models of the mammary gland system and early stage ductal carcinoma in situ (DCIS) in the gland. Pubertal mammary gland development was described first using a two-dimensional, lattice-based hybrid agent-based model description of the mammary terminal end bud (TEB), and then with a three-dimensional lattice-free TEB model. Both models implement a discrete, agent-based description of the cell scale, and a continuum, …