Engineering Commons^™

Post-Polymerization Modification Of Kapton Using Electron Beam Irradiation, Luis A. Hernandez

Mechanical Engineering ETDs

In the present study, the feasibility of chemical modification of electron-irradiated Kapton is investigated. Characterization techniques determined the changes between a pristine, electron irradiated, and a chemically treated, i.e., fluorinated, sample of Kapton. Kapton is a common material in space application as it serves as the exterior surface for space vehicles. Highly aged Kapton have significant material property changes, making them prone to electro-static discharge (ESD) damage. Understanding how Kapton material behaves under space conditions and the possibility of improving its structure and properties is of utmost important. To this end, changes to the physical properties of the material were …

Evaluating Sustainable & Equitable Financing For Pedestrian Infrastructure Maintenance And How The Quality Of Pedestrian Infrastructure Affects The Choice To Walk, Alexis Corning Padilla

Civil Engineering ETDs

In many communities, pedestrian infrastructure is poorly maintained. One challenge is finding sustainable and equitable funding since many municipalities across the country require adjacent property to maintain and repair sidewalks adjacent to their property. These policies are difficult to enforce, may place a high cost on lower-income households, and may be partly responsible for the poor condition of many sidewalks. Therefore, in the first part of this research, we evaluated three alternatives for financing the maintenance of sidewalks in Albuquerque, New Mexico: increasing the gross receipts tax, the gasoline excise tax, or the property tax. We concluded that any of …

An Efficient Multiple-Place Foraging Algorithm For Scalable Robot Swarms, Qi Lu

Computer Science ETDs

Searching and collecting multiple resources from large unmapped environments is an important challenge. It is particularly difficult given limited time, a large search area and incomplete data about the environment. This search task is an abstraction of many real-world applications such as search and rescue, hazardous material clean-up, and space exploration. The collective foraging behavior of robot swarms is an effective approach for this task. In our work, individual robots have limited sensing and communication range (like ants), but they are organized and work together to complete foraging tasks collectively. An efficient foraging algorithm coordinates robots to search and collect …

Application Of Cation Exchange And Nanofiltration To Treat Flue Gas Desulfurization Wastewater, Ayush R. Shahi

Civil Engineering ETDs

Flue gas emitted from coal-fired power plants is one of the major sources of sulfur and nitrogen oxides emissions to the atmosphere in the world today. Although coal use has decreased, it is still a major contributor to such emissions. The Clean Air Act in the United States established regulations for coal-fired power plants to limit SO_x and NO_x emissions into the atmosphere. To meet regulatory requirements, power plants have been using scrubbers to limit their air emissions. Flue-gas desulfurization (FGD) is a pollution prevention method that is employed to limit sulfur dioxide emissions directly in the environment …

Identification Of The Corona Point In Point-To-Plane Geometries In Atmospheric Air, Leonardo Rossetti

Electrical and Computer Engineering ETDs

The minimum sustaining electric field for streamer propagation is directly correlated to the minimum electric field at the corona point. Corona is a product of non-uniform electric fields; the onset of corona occurs before electrical breakdown. As electric fields become increasingly uniform the required field strength to produce corona is increased as well. The field uniformity can be increased until a critical point in which electrical breakdown coincides with the onset of a positive corona, this is known as the corona point.

An experimental setup with a point to plane configuration allows precise changes in electric field uniformity, by gradually …

Design Of A Canine Inspired Quadruped Robot As A Platform For Synthetic Neural Network Control, Cody Warren Scharzenberger

Dissertations and Theses

Legged locomotion is a feat ubiquitous throughout the animal kingdom, but modern robots still fall far short of similar achievements. This paper presents the design of a canine-inspired quadruped robot named DoggyDeux as a platform for synthetic neural network (SNN) research that may be one avenue for robots to attain animal-like agility and adaptability. DoggyDeux features a fully 3D printed frame, 24 braided pneumatic actuators (BPAs) that drive four 3-DOF limbs in antagonistic extensor-flexor pairs, and an electrical system that allows it to respond to commands from a SNN comprised of central pattern generators (CPGs). Compared to the previous version …

Conference Program, Christina Chan, Mattheos Koffas, Steffen Schaffer, Rashmi Kshirsagar

Biochemical and Molecular Engineering XXI

No abstract provided.

Conference Program, Samiul Amin, Paolo Arosio, Miguel Rodrigues

Biological and Pharmaceutical Complex Fluids III: Protein Self-Assembly, Rheology and Interfacial Properties

No abstract provided.

Design And Fabrication Of Peel-Off And Stick Antennas, Jayakrishnan Vijayamohanan

Electrical and Computer Engineering ETDs

Antennas on multiple platforms with the capability to be reused is a novel concept in antenna technologies. This thesis explores the idea of such a flexible antenna that can be stuck on any surface using certain adhesives and be peeled off for reuse for a different purpose. This thesis specifically focuses on the application of being used on small Unmanned Aircraft Systems (sUAVs). Three basic designs are fabricated and investigated. One of them is a reconfigurable meandering monopole, consisting of a PIN diode which resonates at two different frequencies depending on the applied external voltage. A challenge that is addressed …

Development Of Threshold Levels And A Climate-Sensitivity Model Of The Hydrological Regime Of The High-Altitude Catchment Of The Western Himalayas, Pakistan, Muhammad Saifullah, Shiyin Liu, Adnan Ahmad Tahir, Muhammad Zaman, Sajjad Ahmad, Muhammad Adnan, Dianyu Chen, Muhammad Ashraf, Asif Mehmood

Civil and Environmental Engineering and Construction Faculty Research

Water shortages in Pakistan are among the most severe in the world, and its water resources are decreasing significantly due to the prevailing hydro-meteorological conditions. We assessed variations in meteorological and hydrological variables using innovative trend analysis (ITA) and traditional trend analysis methods at a practical significance level, which is also of practical interest. We developed threshold levels of hydrological variables and developed a non-parametric climate-sensitivity model of the high-altitude catchment of the western Himalayas. The runoff of Zone I decreased, while the temperature increased and the precipitation increased significantly. In Zone II, the runoff and temperature increased but the …

Comparative Analysis Of Small Unmanned Aircraft Systems Operations Manuals, Stephen M. Cigal

Student Works

With over 100,000 remote pilots in the United States, individuals and companies are rapidly incorporating unmanned aircraft system technologies into their everyday life and businesses models. The companies that use these technologies must comply with federal and state regulations in order to maintain a safe environment to operate. These operations must also be accepted by the general public. Since the FAA regulations for small unmanned aircraft systems (sUAS) went into effect in 2016, supplemented by additional state and/or local requirements, some companies have generated operations manuals (OM) to ensure consistent, safe flight that meets these requirements. By analyzing the OM’s …

Guiding Principles For Integrally Christian Engineering Work In Industry, Justin R. Vander Werff

Faculty Work Comprehensive List

What is integrally Christian engineering? Or to ask it slightly differently, what does engineering look like if it is faithful and obedient to God’s will as revealed in His Word? I do not think we, as finite and creaturely Christ-followers, can expect to exhaustively determine God’s biblical directive for every facet of engineering and technology on this side eternity. However, if we truly believe that Christ is Lord of all of life and that He calls us to grateful service in everything we do, we need to continue to wrestle with these questions. One framework to help navigate these questions …

Modeling Thermal And Mechanical Cancellation Of Residual Stress From Hybrid Additive Manufacturing By Laser Peening, Guru Madireddy, Chao Li, Jingfu Liu, Michael P. Sealy

Department of Mechanical and Materials Engineering: Faculty Publications

Additive manufacturing (AM) of metals often results in parts with unfavorable mechanical properties. Laser peening (LP) is a high strain rate mechanical surface treatment that hammers a workpiece and induces favorable mechanical properties. Peening strain hardens a surface and imparts compressive residual stresses improving the mechanical properties of a material. This work investigates the role of LP on layer-by-layer processing of 3D printed metals using finite element analysis. The objective is to understand temporal and spatial residual stress development after thermal and mechanical cancellation caused by cyclically coupling printing and peening. Results indicate layer peening frequency is a critical process …

The Importance Of The Instantaneous Phase In Detecting Faces With Convolutional Neural Networks, Luis Armando Sanchez Tapia

Electrical and Computer Engineering ETDs

Convolutional Neural Networks (CNN) have provided new and accurate methods for processing digital images and videos. Yet, training CNNs is extremely demanding in terms of computational resources. Also, for simple applications, the standard use of transfer learning also tends to require far more resources than what may be needed. Furthermore, the final systems tend to operate as black boxes that are difficult to interpret.

The current thesis considers the problem of detecting faces from the AOLME video dataset. The AOLME dataset consists of a large video collection of group interactions that are recorded in unconstrained classroom environments. For the thesis, …

Stamina: Stochastic Approximate Model-Checker For Infinite-State Analysis, Thackur Neupane, Chris J. Myers, Curtis Madsen, Hao Zheng, Zhen Zhang

Electrical and Computer Engineering Faculty Publications

Stochastic model checking is a technique for analyzing systems that possess probabilistic characteristics. However, its scalability is limited as probabilistic models of real-world applications typically have very large or infinite state space. This paper presents a new infinite state CTMC model checker, STAMINA, with improved scalability. It uses a novel state space approximation method to reduce large and possibly infinite state CTMC models to finite state representations that are amenable to existing stochastic model checkers. It is integrated with a new property-guided state expansion approach that improves the analysis accuracy. Demonstration of the tool on several benchmark examples shows promising …

High Octane Number Gasoline-Ether Blend, Hany A. Elazab Dr

Chemical Engineering

Gasoline produced in Egypt is a low-grade gasoline that contains high concentration of harmful components that are having a toll on our environment. In addition, those pollutants cause countless diseases and deaths annually to the Egyptian population. This paper targets two main sectors in the production of commercial gasoline. The improvement engine efficiency through the upgrading of octane number is first experimented by using a blendstock that ranges from gasoline fractions and Isomerates. An optimum was then chosen depending on the results obtained from different tests. Through those experiments, it was determined which samples obeyed the EU regulation for transportation …

Physico-Chemical Characteristics Of Ethanol–Diesel Blend Fuel, Tarek M. Aboul-Fotouh, Eslam Alaa, M. A. Sadek, Hany A. Elazab Dr

Chemical Engineering

In this research we are discussing the physicochemical characteristics of sweet diesel after desulphurization alone and also these characteristics are tested with the adding of high purity HPLC ethanol (99.9%). Those fuel properties of ethanol blended with diesel were experimentally determined to find their stability and to increase their properties and efficiency in the diesel engines. First we made 4 blends of diesel with ethanol and the fifth sample was pure diesel. The samples were 0% ethanol and 100 % diesel, the second sample was 5% ethanol and 95 % diesel, the third sample was 10 % ethanol and 90% …

Evaluation Of The Cracking Performance Of Geogrid-Reinforced Hot-Mix Asphalt For Airfield Applications, Daniel Offenbacker

Theses and Dissertations

The objective of this study was to evaluate the fatigue cracking performance of geogrid-reinforced Hot-Mix Asphalt (HMA) for use in airfield runways. An airfield HMA mixture with four different geogrid types were selected for this study. The geogrids varied in tensile strength, coating type, opening size, thickness, and fiber material. Several different laboratory performance tests were conducted (Dynamic Complex Modulus, DCM, Overlay Test, OT, and Indirect Tensile Strength, ITS) and the fatigue and/or cracking performance was evaluated. Additionally, different approaches were adopted or developed for the modeling of geogrids in HMA using Finite Element Modeling (FEM). Finally, a Life-Cycle Cost …

Computational Investigation Of The Interactions Between Bioactive Compounds And Biological Assemblies, Tye D. Martin

Biomedical Engineering ETDs

Small, biologically active molecules with unique properties and applications are potential solutions to a wide range of threats to global health including infectious agents and neurodegenerative disease. Experimental studies on a class of oligomeric p-phenylene ethynylenes (OPEs) have shown potential both as bioactive antimicrobials and fluorescent sensing agents for tracking amyloid-β (Aβ) aggregates found in Alzheimer’s Disease (AD). A second type of small molecule with potential applications in AD therapy, curcumin, has been found to interfere with Aβ fibril growth. Curcumin also attenuates Aβ-membrane interactions and Aβ toxicity. Our goal has been to use computational techniques to better understand the …

Quantifying Thermal Refugia Connectivity By Combining Temperature Modeling, Distributed Temperature Sensing, And Thermal Infrared Imaging, Jessica R. Dzara, Bethany T. Neilson, Sarah E. Null

Civil and Environmental Engineering Faculty Publications

Watershed-scale stream temperature models are often one-dimensional because they require fewer data and are more computationally efficient than two- or three-dimensional models. However, one-dimensional models assume completely mixed reaches and ignore small-scale spatial temperature variability, which may create temperature barriers or refugia for cold-water aquatic species. Fine spatial- and temporal-resolution stream temperature monitoring provides information to identify river features with increased thermal variability. We used distributed temperature sensing (DTS) to observe small-scale stream temperature variability, measured as a temperature range through space and time, within two 400 m reaches in summer 2015 in Nevada's East Walker and main stem Walker …

Interactions Of Bacteria With Monolithic Lateral Silicon Nanospikes Inside A Microfluidic Channel, Lei Li, Feng Tian, Hao Chang, Jie Zhang, Cheng Wang, Wei Rao, Huan Hu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents a new strategy of integrating lateral silicon nanospikes using metal-assisted chemical etching (MacEtch) on the sidewall of micropillars for on-chip bacterial study. Silicon nanospikes have been reported to be able to kill bacteria without using chemicals and offer a new route to kill bacteria and can prevent the overuse of antibiotics to reduce bacteria. We demonstrated a new methodology to fabricate a chip with integrated silicon nanospikes onto the sidewalls of micropillars inside the microfluidic channel and attested its interactions with the representative gram-negative bacteria Escherichia coli. The results of colony-forming unit (CFU) calculation showed that 80% …

City Of New Smyrna Beach Solar Feasibility Assessment - City Hall Annex, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

This review and solar assessment is organized by component with brief description of intended details, challenges and recommendations.

Building: City of New Smyrna Beach, City Hall Annex (Renovation of a portion of the Historic First Baptist Church of New Smyrna Beach) Year of Construction: 1920's[1] Building Use: Renovation will create spaces for City workers and a new City Council Chambers Conditioned area: 1^st floor = 7856 ft² 2^nd floor = 3,967 ft² Total = 11,823 ft²[2]

[1] New Smyrna Beach Property Appraiser's website states 1920, historic marker states circa 1929. [2] New Smyrna …

Verification Of Stochastic Reach-Avoid Using Rkhs Embeddings, Adam J. Thorpe

Electrical and Computer Engineering ETDs

A solution to the terminal-hitting and first-hitting stochastic reach-avoid problem for a Markov control process is presented. This solution takes advantage of a nonparametric representation of the stochastic kernel as a conditional distribution embedding within a reproducing kernel Hilbert space (RKHS). Because the disturbance is modeled as a data-driven stochastic process, this representation avoids intractable integrals in the dynamic recursion of the reach-avoid problem since the expectations can be calculated as an inner product within the RKHS. An example using a high-dimensional chain of integrators is presented, as well as for Clohessy-Wiltshire-Hill (CWH) dynamics.

Method For Fabrication Of A Soft-Matter Printed Circuit Board, Carmel Majidi, Tong Lu, Eric J. Markvicka

Department of Mechanical and Materials Engineering: Faculty Publications

A fabrication process for soft - matter printed circuit boards is disclosed in which traces of liquid - phase Ga - In eutectic ( eGaIn ) are patterned with UV laser micromachining ( UVLM ) . The terminals of the elastomer - sealed LM circuit connect to the surface mounted chips through vertically aligned columns of eGaIn - coated ferromagnetic micro spheres that are embedded within an interfacial elastomer layer .

Is Transportation Planning Effective? A Critical Review Of Long-Range Regional Transportation Planning In The United States, Razieh Nadafianshahamabadi

Civil Engineering ETDs

The Federal-Aid Highway Act requires urban areas with a population greater than 50,000 to create Metropolitan Planning Organizations (MPOs) to ensure that funding for transportation projects and programs are based on a continuing, cooperative, and comprehensive planning process. A major responsibility of each MPO is the creation of a long-range transportation plan (LRTP) that addresses the transportation needs of a metropolitan region over the next twenty years or more. While long-range regional transportation planning goals have grown to include a wide range of concerns and technical methods for evaluating planning scenarios have advanced substantially over the past 50 years, there …

Resolving Intravoxel White Matter Structures In The Human Brain Using Regularized Regression And Clustering, Andrea Hart, Brianna Smith, Sean Smith, Elijah Sales, Jacqueline Hernandez-Camargo, Yarlin Mayor Garcia, Felix Zhan, Lori Griswold, Brian Dunkelberger, Michael R. Schwob, Sharang Chaudhry, Justin Zhan, Laxmi Gewali, Paul Oh

Computer Science Faculty Research

The human brain is a complex system of neural tissue that varies significantly between individuals. Although the technology that delineates these neural pathways does not currently exist, medical imaging modalities, such as diffusion magnetic resonance imaging (dMRI), can be leveraged for mathematical identification. The purpose of this work is to develop a novel method employing machine learning techniques to determine intravoxel nerve number and direction from dMRI data. The method was tested on multiple synthetic datasets and showed promising estimation accuracy and robustness for multi-nerve systems under a variety of conditions, including highly noisy data and imprecision in parameter assumptions.

Non-Conventional Mechanism Of Ferroelectric Fatigue Via Cation Migration, Anton Ievlev, Santosh Kc, Rama Vasudevan, Yunseok Kim, Xiaoli Lu, Marin Alexe, Valentino Cooper, Sergei Kalinin, Olga Ovchinnikova

Faculty Publications

The unique properties of ferroelectric materials enable a plethora of applications, which are hindered by the phenomenon known as ferroelectric fatigue that leads to the degradation of ferroelectric properties with polarization cycling. Multiple microscopic models explaining fatigue have been suggested; however, the chemical origins remain poorly understood. Here, we utilize multimodal chemical imaging that combines atomic force microscopy with time-of-flight secondary mass spectrometry to explore the chemical phenomena associated with fatigue in PbZr0.2Ti0.8O3 (PZT) thin films. Investigations reveal that the degradation of ferroelectric properties is correlated with a local chemical change and migration of electrode ions into the PZT structure. …

Iii-V Nbn Focal Plane Arrays: Radiometric Characteristics As A Function Of Detector Cutoff Wavelength, Victor Darie Pepel

Electrical and Computer Engineering ETDs

Summarized here are the measured radiometric characteristics of three Infrared III-V InAsSb/AlAsSb/InAsSb-based nBn focal plane arrays (FPAs) in the SWIR to MWIR range with cutoff wavelengths of 2.85 µm, 3.3 µm and 4.2 µm at the nominal operating temperature of 150 K. Herein referred to by their respective cutoff wavelengths, the nBn detectors are characterized across the temperature range of 130 K to 180 K. The optical response and noise characteristics are examined as a function of cutoff wavelength, and a comparison of dark current density is made to HgTeCd photodiodes using the Rule ‘07 heuristic.

The 2.85 µm, 3.3 …

Introducing Cornerstone Courses Into Electrical And Computer Engineering Curriculum, Branimir Pejcinovic

Electrical and Computer Engineering Faculty Publications and Presentations

Almost all engineering programs have some form of final, culminating design experience, which is typically taught as a senior year capstone design course. Due to ABET requirements these are team and project based. Many programs will also have projects interspersed among required and elective courses, but these tend to be overrepresented in freshman year. We have recently introduced a set of courses during sophomore year that mimic our approach to capstone courses and provide authentic engineering design experience. These so-called cornerstone courses provide scaffolding by introducing all of the components of teamwork and design process but in a less formal …

Control Of Rigid Robots With Large Uncertainties Using The Function Approximation Technique, Donald Ebeigbe

ETD Archive

This dissertation focuses on the control of rigid robots that cannot easily be modeled due to complexity and large uncertainties. The function approximation technique (FAT), which represents uncertainties as finite linear combinations of orthonormal basis functions, provides an alternate form of robot control - in situations where the dynamic equation cannot easily be modeled - with no dependency on the use of model information or training data. This dissertation has four aims - using the FAT - to improve controller efficiency and robustness in scenarios where reliable mathematical models cannot easily be derived or are otherwise unavailable. The first aim …