Engineering Commons^™

Array Of Surface-Confined Glow Discharges In Atmospheric Pressure Helium: Modes And Dynamics, D. Li, D. X. Liu, Q. Y. Nie, H. P. Li, H. L. Chen, M. G. Kong

Bioelectrics Publications

Array of atmospheric pressure surface discharges confined by a two-dimensional hexagon electrode mesh is studied for its discharge modes and temporal evolution so as to a theoretical underpinning to their growing applications in medicine, aerodynamic control, and environmental remediation. Helium plasma surface-confined by one hexagon-shaped rim electrode is shown to evolve from a Townsend mode to a normal and abnormal glow mode, and its evolution develops from the rim electrodes as six individual microdischarges merging in the middle of the hexagon mesh element. Within one hexagon element, microdischarges remain largely static with the mesh electrode being the instantaneous cathode, but …

Enhancing Agility Of Supply Chains Using Stochastic, Discrete Event And Physical Simulation Models, Alok K. Verma

Engineering Technology Faculty Publications

Managing supply chains in today’s distributed manufacturing environment has become more complex. To remain competitive in today’s global marketplace, organizations must streamline their supply chains. The practice of coordinating the design, procurement, flow of goods, services, information and finances, from raw material flows to parts supplier to manufacturer to distributor to retailer and finally to consumer requires synchronized planning and execution. Efficient and effective supply chain management assists an organization in getting the right goods and services to the place needed at the right time, in the proper quantity and at acceptable cost. Managing this process involves developing and overseeing …

Intelligent Sensing Based On Low Cost Unmanned Aerial Vehicles (Uav) For Bridge Condition Assessment, Theodore Teates, Austin Boyd, Chung-Hao Chen

Electrical & Computer Engineering Faculty Publications

The eventual completion of this project envisions the use of an Unmanned Aerial Vehicle (UAV) to inspect bridge infrastructure. This project may also be expanded to encompass general object detection and inspection in order to unburden this technology so that it may reach its fullest potential. The project requires research and development in three distinct areas of image processing, control structures, and integration of systems. Initial undergraduate research sets the base knowledge for the overall project, explores the areas of concentration that are desired to expand upon in the future project, and provides a base UAV model that new researchers …

Mathematical Methods Applied To Digital Image Processing, Yi-Hung Liu, Chung Hao Chen, Paul C.P. Chao

Electrical & Computer Engineering Faculty Publications

Introduction: Digital image processing (DIP) is an important research area since it spans a variety of applications. Although over the past few decades there has been a rapid rise in this field, there still remain issues to address. Examples include image coding, image restoration, 3D image processing, feature extraction and analysis, moving object detection, and face recognition. To deal with these issues, the use of sophisticated and robust mathematical algorithms plays a crucial role. The aim of this special issue is to provide an opportunity for researchers to publish their latest theoretical and technological achievements in mathematical methods and their …

Stability Of High Band Gap P3ht: Pcbm Organic Solar Cells Using Tiox Interfacial Layer, Kurniawan Foe, Gon Namkoong, Matthew Samson, Enas M. Younes, Ilho Nam, Tarek M. Abdel-Fattah

Electrical & Computer Engineering Faculty Publications

We fabricated a poly [3-hexylthiophene] (P3HT) and [6,6] -phenyl-C61-butyric acid methyl ester (PC₆₁BM with the TiO_x layer. We found that a solution based TiO_x coated at a spin speed of 3000 rpm improved the photon absorption of the active layer. An optimized TiO_x layer was also used as the interfacial layer to investigate the stability of P3HT: PC₆₁BM OPC. After 70 days of storage, we observed that the short-circuit current density (J_SC) dropped by 16.2%, fill factor (FF) dropped by 10.6%, and power conversion efficiency (PCE) dropped approximately by 25%, while …

Lessons In On-Campus And Distance Learning Delivery Of An Introductory Naval Architecture Course, Jennifer G. Michaeli

Engineering Technology Faculty Publications

This paper describes the author’s experiences in multi-mode (face-to-face and online) delivery of an introductory-level course on the topic of Naval Architecture geared towards anaudience of engineering and engineering technology undergraduate students with no previousmaritime background. The goal of this course is to expose talented undergraduate engineering students to the marine industry and to prepare those interested in pursing a career in this field with an introductory understanding of the complex nature of designing and building ships and other marine vessels. This course was offered in Spring 2013 and Fall 2013 to a group of engineering and engineering technology students. …

Hydrothermal Processing Of Biomass For Biofuels, Sandeep Kumar

Civil & Environmental Engineering Faculty Publications

[First paragraph] In recent years, significant research interests have been placed on the conversion of non-food biomass resources such as lignocellulosic biomass (terrestrial) and algae (aquatic) to biofuels. Among all the alternative or renewable energy options, biomass is the only resource which is carbon neutral and can potentially replace part of fossil fuels use as liquid transportation fuels as well as contribute to electricity generation. Therefore, it can play a significant role in partially replacing oil, natural gas, and coal utilization for heat and energy generation. However, high moisture content of fresh biomass or algae is one of the major …

Generator Polynomial Formulation For Parallel Counters With Applications, Lee A. Belfore Ii

Electrical & Computer Engineering Faculty Publications

Parallel counters have been studied for several decades as a component in high speed multipliers and multi-operand adder circuits. Using a generator polynomial as a formalism for describing parallel counters in the general case, parallel counter properties can be derived and inferred. Furthermore, the structure and decomposition of the generator polynomial can suggest different implementation strategies. These include simple implementations of (7,3) and (15,4) parallel counters. By grouping factors, the design of a fast (7,3) parallel counter is presented. Finally, the generator polynomial is extended to permit factors of different weights. This extension provides a means for describing the design …

Identifiability Of Additive Actuator And Sensor Faults By State Augmentation, Suresh M. Joshi, Oscar R. Gonzalez, Jason M. Upchurch

Electrical & Computer Engineering Faculty Publications

A class of FDI (fault detection and identification) methods for bias-type actuator and sensor faults was explored from the point of view of fault identifiability. The methods use banks of Kalman-Bucy filters (KBFs) to detect faults, determine the fault pattern, and estimate the fault values. A complete characterization of conditions for identifiability of bias-type actuator faults, sensor faults, and simultaneous actuator and sensor faults was presented. It was shown that FDI of simultaneous actuator and sensor faults is not possible using these methods when all sensors have unknown biases. The fault identifiability conditions were demonstrated via numerical examples. The analytical …

Atomic Layer Deposition Of Nanolaminate Structures Of Alternating Pbte And Pbse Thermoelectric Films, K. Zhang, A. D. Ramalingom Pillai, K. Bollenbach, D. Nminibapiel, W. Cao, H. Baumgart

Electrical & Computer Engineering Faculty Publications

For this study PbTe and PbSe thin film nanolaminates have been prepared on silicon substrates with native oxide by Atomic Layer Deposition (ALD) using lead(II)bis(2,2,6,6-tetramethyl-3,5-heptanedionato) (Pb(C₁₁H₁₉O₂)(₂), (trimethylsilyl) telluride ((Me₃Si)₂Te) and bis-(triethyl silyl) selane ((Et₃Si)₂Se) as ALD precursors for lead, tellurium and selenium. The experimental evidence revealed the ALD growth of lead telluride and lead selenide followed the Vollmer-Weber island growth mode. We found a strong dependence of the nucleation process on the temperature. In this paper, we present the optimized conditions for growing PbTe …

Physical Analysis Of Vo2 Films Grown By Atomic Layer Deposition And Rf Magnetron Sputtering, Madhavi Tangirala, Kai Zhang, David Nminibapiel, Venkateswara Pallem, Christian Dussarrat, Wei Cao, Thomas N. Adam, Corbet S. Johnson, Hani E. Elsayed-Ali, Helmut Baumgart

Electrical & Computer Engineering Faculty Publications

Among the many vanadium suboxides and different stoichiometries, VO₂ has received considerable attention due to its remarkable metal-insulator transition (MIT) behavior, which causes a significant reversible change in its electrical and optical properties occurring across the phase transition at 67°C. The initially amorphous VO₂ thin films were fabricated by the emerging, Atomic Layer Deposition (ALD) technique with (tetrakis[ethylmethylamino]vanadium) {V(NEtMe)₄} as precursor and H₂O vapor as oxidation agent. For benchmarking we have also used the RF Magnetron Sputtering technique to deposit metallic vanadium thin films, which were later oxidized during furnace annealing. Post annealing of …

Numerical Study Of Lipid Translocation Driven By Nanoporation Due To Multiple High-Intensity, Ultrashort Electrical Pulses, Viswanadham Sridhara, Ravindra P. Joshi

Electrical & Computer Engineering Faculty Publications

The dynamical translocation of lipids from one leaflet to another due to membrane permeabilization driven by nanosecond, high-intensity (>100 kV/cm) electrical pulses has been probed. Our simulations show that lipid molecules can translocate by diffusion through water-filled nanopores which form following high voltage application. Our focus is on multiple pulsing, and such simulations are relevant to gauge the time duration over which nanopores might remain open, and facilitate continued lipid translocations and membrane transport. Our results are indicative of a N^1/2 scaling with pulse number for the pore radius. These results bode well for the use of pulse …

Plasma Processes And Polymers Special Issue On: Plasma And Cancer, Mounir Laroussi, Michael Keidar

Electrical & Computer Engineering Faculty Publications

During the last two decades, research efforts on the application of low temperature plasmas in biology and medicine have positioned nonequilibrium lowtemperature plasmas as a technology that has the potential of revolutionizing healthcare.[1,2] Low temperature plasmas can be applied in direct contact with living tissues to inactivate bacteria,[3] to disinfect wounds and accelerate wound healing,[4] and to induce damage in some cancer cells.[5–11]

Optical Characterization Of Nanomaterials, Mun S. Jeong, Gon Namkoong, Clare C. Byeon, Jong Su Kim, Hong S. Lee

Electrical & Computer Engineering Faculty Publications

No abstract provided.

A Nonrigid Registration Method For Correcting Brain Deformation Induced By Tumor Resection, Yixun Liu, Chengjun Yao, Fotis Drakopoulos, Jinsong Wu, Liangfu Zhou, Nikos Chrisochoides

Computer Science Faculty Publications

Purpose: This paper presents a nonrigid registration method to align preoperative MRI with intraoperative MRI to compensate for brain deformation during tumor resection. This method extends traditional point-based nonrigid registration in two aspects: (1) allow the input data to be incomplete and (2) simulate the underlying deformation with a heterogeneous biomechanical model.

Methods: The method formulates the registration as a three-variable (point correspondence, deformation field, and resection region) functional minimization problem, in which point correspondence is represented by a fuzzy assign matrix; Deformation field is represented by a piecewise linear function regularized by the strain energy of a heterogeneous biomechanical …

Naval Aviation Squadron Risk Analysis Predictive Bayesian Network Modeling Using Maintenance Climate Assessment Survey Results, Harry Michael Robinson

Computational Modeling & Simulation Engineering Theses & Dissertations

Associated risks in flying have resulted in injury or death to aircrew and passengers, and damage or destruction of the aircraft and its surroundings. Although the Naval Aviation's flight mishap rate declined over the past 60 years, the proportion of human error causal factors has stayed relatively constant at about 80%. Efforts to reduce human errors have focused attention on understanding the aircrew and maintenance actions occurring in complex systems.

One such tool has been the Naval Aviation squadrons' regular participation in survey questionnaires deigned to measure respondent ratings related to personal judgments or perceptions of organizational climate for meeting …

Human Capital Management Within The Federal Government Utilizing Generational Stratification With A Focus On Generation Y, Ian Nathaniel Barford

Engineering Management & Systems Engineering Theses & Dissertations

With many individuals in the Baby Boomer generation eligible to retire, many open positions will need to be filled by other Baby Boomers, or those from Generation X or Generation Y. Private industry has taken note of this and has been exploring workplace differences between Generation Y, Generation X, and Baby Boomers. Unfortunately for the federal government, data shows Generation Y is also separating; specifically quitting for unknown reasons. Understanding this apparent dichotomy between Generation Y and Generation X and Baby Boomer federal government employees is a current knowledge gap within the federal government's strategic human capital management focus.

From …

Electrotransfer Of Single-Stranded Or Double-Stranded Dna Induces Complete Regression Of Palpable B16.F10 Mouse Melanomas, Loree Heller, Vesba Todorovic, Maja Cemazar

Bioelectrics Publications

Enhanced tumor delivery of plasmid DNA with electric pulses in vivo has been confirmed in many preclinical models. Intratumor electrotransfer of plasmids encoding therapeutic molecules has reached Phase II clinical trials. In multiple preclinical studies, a reduction in tumor growth, increased survival or complete tumor regression have been observed in control groups in which vector or backbone plasmid DNA electrotransfer was performed. This study explores factors that could produce this antitumor effect. The specific electrotransfer pulse protocol employed significantly potentiated the regression. Tumor regression was observed after delivery of single-stranded or double-stranded DNA with or without CpG motifs in both …

Quantifying Risks Of Climate Change And Sea Level Rise To Naval Station Norfolk (Serdp Rc-1701), Kelly Burks-Copes

October 2, 2013: Quantifying Risks and Moving Forward

No abstract provided.

Dimensionless Criteria For Selecting Tidally-Influenced Advective-Dispersive Desalination Brine Mixing Plume Characterization Models, Alireza Shahvari

Civil & Environmental Engineering Theses & Dissertations

The very nature of requirements for implementing a desalination process is highly spatial due to the need to secure both a source for the operation and sink for brine dilution. Thus, the applicable coastal location is bound to natural tidal mixing characteristics and subjected to a near- or a far-field availability for source and sink. Mixing characteristics of coastal waters are very different from one point to another due to the spatiotemporal tidal characteristic in loco in a manner that it can vary from being highly advective to completely dispersive dominant. Once a location is identified, estimation of corresponding water …

Control System Of An Atomic Layer Deposition (Ald) Machine, Nitin Vishnu Hegde

Electrical & Computer Engineering Theses & Dissertations

Atomic Layer Deposition is one of the most efficient deposition processes for obtaining ultrathin films. The deposition by this process happens one atomic layer at a time. ALD is known for its precision and ability to develop quality films with great thickness control. ALD machines simultaneously control DC and AC currents, low pressure operations, temperature control and heating (up to 500'C), precision flow control, precision timing intervals for deposition (milli-second intervals) and constantly monitor temperature. Such a high control comes at a high price. Furthermore, at the university level, the capacity to modify or enhance a machine is critical but …

Synthesis And Optimization Of Vo₂ Thin Films For Phase Transition Applications By Atomic Layer Deposition And Rf Magnetron Sputtering, Madhavi Tangirala

Electrical & Computer Engineering Theses & Dissertations

Among many Vanadium oxides and suboxides, VO₂ has received considerable attention due to its remarkable metal-insulator transition (MIT) or semiconductor-metal transition (SMT) behavior, a reversible change in its electrical and optical properties that occurs due to a phase transition near a temperature of 68°C. Electrically, the resistivity of VO₂ can be changed as large as 4-5 orders of magnitude. Optically, the transmittance drops dramatically above the transition temperature in the metallic state where the VO₂ film becomes highly reflective in the infrared region. All these properties result in structural phase transformation from a low temperature monoclinic to …

Operation And Modification Of A B-Stage For Efficient Nitrogen Removal In An A/B Process Pilot Study, Ryder Bunce

Civil & Environmental Engineering Theses & Dissertations

Hampton Roads Sanitation District's Chesapeake-Elizabeth Wastewater Treatment Plant is a High-Rate Activated Sludge (HRAS) plant with no primary clarifiers. The plant operates at an SRT of 1.5 - 2 days and does not perform biological nitrogen removal (BNR). By 2021 HRSD anticipates the plant will be included in a bubble permit, resulting in a total nitrogen (TN) effluent target of approximately 5-8 mg/L. Converting the plant to a conventional BNR process would require a significant increase in reactor volume. Capital costs for the upgrade are estimated at 125 -150 million dollars, with a dramatic increase in operating costs as well. …

Use Of Immersive Visualization For The Control Of Dental Anxiety During Dental Hygiene Treatment, Carmelo Padrino-Barrios

Dental Hygiene Theses & Dissertations

Purpose: The purpose of this study was to determine the effectiveness of immersive visualization (IV) therapy, a technique that provides visual and stereoscopic display through the use of eyewear, in anxious patients during an oral prophylaxis. Methods: A convenience sample of thirty adults was enrolled. A split mouth design was utilized. Subjects were randomly divided into two groups: group A (use of IV for the right side of the mouth), and group B (use of IV for the left side of the mouth). Subjects received a full mouth oral prophylaxis (removal of supra and subgingival calculus and selective polishing), always …

Denitrification And Biological Phosphorus Removal Using Focused, Pulse-Treated, Thickened Waste Activated Sludge As An Internal Carbon Source, Holly Anne Hillard

Civil & Environmental Engineering Theses & Dissertations

Recent research shows that an internal carbon source, derived from the treatment of waste activated sludge (WAS), could be used as an alternative to external carbon sources for denitrification in biological wastewater treatment processes. In this study, a thickened waste activated sludge (TWAS) treatment technology, developed by the company OpenCEL, was used to treat TWAS with pulsed electric fields (PEF) to transform it into an organic substrate for heterotrophic denitrification in a biological nutrient removal (BNR) system. If effective, this technique could significantly reduce the external carbon source demand.

To determine the utility of OpenCEL-treated TWAS as an internal carbon …

Theory Of Constraints Project Management In A Manufacturing Environment, Shihching Kraft

Mechanical & Aerospace Engineering Theses & Dissertations

The following thesis covers the concepts of Theory of Constraints (TOC) Project Management. Introduced by Eliyahu M. Goldratt in I 984, TOC is a management philosophy that focuses on the use of critical chain project management to prioritize everyday tasks in a company. In TOC Project Management, there is always at least one resource constraint that limits the speed at which projects are completed. TOC management philosophy also recognizes that most projects in the manufacturing industry face unknown schedule delays that could cause projects to be completed late or over the planned budget. During project plan creation, plans are developed …

New Test Capabilities For The 0.3-Meter Transonic Cryogenic Wind Tunnel, Ben D. Phillips

Mechanical & Aerospace Engineering Theses & Dissertations

The small-scale, cryogenic, and high pressure characteristics of the 0.3-Meter Transonic Cryogenic Tunnel provide a unique, high-Reynolds number research capability. However, the facility is currently restricted by its reliance on a two-dimensional adaptive wall test section coupled with an inadequate facility control system. Access to the test section is restricted, the walls require excess time for convergence and are mechanically constrained by a wall jacking system that degrades under cyclic cryogenic operations, and the tunnel requires excessive time to reach the set point, particularly at low Mach numbers. As a result, productivity and operational efficiency are limited, leading to expensive …

Examination Of Micromotion-Induced Transient Effects Of Brain Tissue Interfaced With A Neural Probe, Michael A. Polanco

Mechanical & Aerospace Engineering Theses & Dissertations

Neural probes are utilized to obtain information regarding the activity of brain cells for neural stimulation. The functional longevity of a probe is dependent upon its ability to minimize injury risk during insertion and the recording period in vivo, which could be related to micromotion-related strain between the probe and surrounding tissue. A series of finite element analyses were conducted using the nonlinear transient dynamic code LSDYNA (LSTC, Livermore, CA) to study the strain induced within the brain in an area around a neural probe. A variety of displacement pulses were input into the brain, first where a high magnitude, …

An Investigation Of Unsteady, In-Cylinder Flows Of A Mock-Up Internal Combustion Engine Using Particle Image Velocimetry, David Schleeper

Mechanical & Aerospace Engineering Theses & Dissertations

Particle Image Velocimetry is frequently used in fluid mechanics and aerodynamics research to provide accurate, quantitative information on the instantaneous structure of a variety of flow fields. This technique provides a nonintrusive means of capturing vital, whole-field details of internal and external flows, such as vortex size and strength, not usually possible through other flow investigation techniques. Due to practical difficulties, the utilization of this method for the study of combustion chamber flow within an internal combustion engine is still relatively uncommon. This study used a TSI Particle Image Velocimetry system to identify two-dimensional flow patterns and velocities on a …

Photovoltaic Tracker Optimization With Unique Fault Detection And Enhanced Combiner System, Caitlin Nicole Conway

Electrical & Computer Engineering Theses & Dissertations

Renewable energy resources are rapidly becoming extremely important as the world's energy consumption continues to rise. The most popular of these resources is solar energy and more specifically photovoltaic energy. Currently, solar modules on the market are still not highly efficient. In order to increase the productivity of solar energy systems, larger fixed-panel photovoltaic systems or tracking photovoltaic systems are utilized. The major disadvantage of larger photovoltaic systems is the increased space requirements. Therefore, tracking photovoltaic systems are the best alternative to achieve higher solar energy yields.

To date, the only method of monitoring tracking photovoltaic systems is with the …