Engineering Commons^™

Cavity-Coupled Plasmonic Systems For Enhanced Light-Matter Interactions, Abraham Vazquez-Guardado

Electronic Theses and Dissertations

Light-matter interaction is a pivotal effect that involves the synergetic interplay of electromag- netic fields with fundamental particles. In this regard localized surface plasmons (LSP) arise from coherent interaction of the electromagnetic field with the collective oscillation of free electrons in confined sub-wavelength environments. Their most attractive properties are strong field en- hancements at the near field, highly inhomogeneous, peculiar temporal and spatial distributions and unique polarization properties. LSP systems also offer a unique playground for fundamental electromagnetic physics where micro-scale systemic properties can be studied in the macro-scale. These important properties and opportunities are brought up in this work …

A Reliable Data Provenance And Privacy Preservation Architecture For Business-Driven Cyber-Physical Systems Using Blockchain, Xueping Liang, Sachin Shetty, Deepak K. Tosh, Juan Zhao, Danyi Li, Jihong Liu

VMASC Publications

Cyber-physical systems (CPS) including power systems, transportation, industrial control systems, etc. support both advanced control and communications among system components. Frequent data operations could introduce random failures and malicious attacks or even bring down the whole system. The dependency on a central authority increases the risk of single point of failure. To establish an immutable data provenance scheme for CPS, the authors adopt blockchain and propose a decentralized architecture to assure data integrity. In business-driven CPS, end users are required to share their personal information with multiple third parties. To prevent data leakage and preserve user privacy, the authors isolate …

Introduction: Metrics, Modeling And Simulation For Cyber Physical Systems, Barry Ezell, Luanne Burns

VMASC Publications

[Introduction] In recent years, there has been a massive increase in cyber crime. Cyber breeches have become ubiquitous. The US government is attempting to adapt through legislation and policy. For instance, business in the defense industrial base must be in compliance of NIST 80-71 by 31 December 2017. Insurance companies as well are beginning to build actuaries on cyber risk. Along with NIST, there are many cyber frameworks that exist, each with their own following. Recently, companies have sought mapping from one framework to another but this is imperfect solution because some frameworks are exclusively technical control measures with very …

Two Essays On Whole Farm Modeling And Crop Marketing In Western Kentucky, Benjamin A. Martin

Theses and Dissertations--Agricultural Economics

This thesis is composed of two essays that investigate whole farm planning and crop marketing in western Kentucky. In the first essay, contracting decisions between food corn producers and a mill are analyzed to observe factors affecting the bushel amount farmers contract. Unbalanced panel data containing seven years’ worth of pricing and contract information are used with a fixed-effects model to generate parameter estimates and quantify their effect on bushels contracted. It was found that contract attributes, market condition, and relationship-specific assets had a significant effect on producers’ food corn contracting decisions. The second essay utilizes mixed-integer programming to optimize …

Development Of A Capacitive Photocurrent Scanning Microscope With Carrier Depletion Super-Resolution., Austin Levi Carver

Electronic Theses and Dissertations

This dissertation discusses the development and refinement of a new two-dimensional imaging technique, funded in part through a NSF MRI equipment development grant. Capacitive-Photocurrent (CPC) spectroscopy allows for the probing of samples without the requirement of free-carrier collection. The CPC technique allows for the studying of various states within a material. With this electronic measurement technique, we developed a scanning technique, scanning-CPC, that provides two-dimensional material property images without requiring environments that must be high-vacuum, humidity-controlled, or temperature-controlled. This new technique also provides two-dimensional, electronic mapping without damaging samples. With this successful result, we then modified an existing resolution improving …

Effectiveness Of Drafting Models For Engineering Technology Students And Impacts On Spatial Visualization Ability: An Analysis And Consideration Of Critical Variables, Petros J. Katsioloudis, Jill E. Stefaniak

STEMPS Faculty Publications

Results from a number of studies indicate that the use of drafting models can positively influence the spatial visualization ability for engineering technology students. However, additional variables such as light, temperature, motion and color can play an important role but research provides inconsistent results. Considering this, a set of 5 quasi-experimental studies, was conducted to identify additional critical variables. According to the results, a dynamic, 3Dprinted drafting model, presented with a blue background under lighting conditions between 500–750 lux had the highest impact on spatial visualization ability of engineering technology students.

Investigation Of Ribbed Dome Including Tuned Mass Damper, Ali Parva

Civil & Environmental Engineering Master's Projects

This research report presents the outcome of an investigation of lightweight ribbed steel dome structure. The proposed ribbed dome structure is studied both numerically and experimentally under static, natural vibration, and base excitation conditions. The base excitation is considered in the form of a sinusoidal as well as seismic loading in the form of a scaled-down 1940 El Centro earthquake. A numerical study of the ribbed dome is also conducted including a tuned mass damper (TMD). The performance of the dome is also compared with that of a hexagonal vertical structure showing a superior response of the dome under seismic …

A Purification And In Vitro Activity Assay For A (P)Ppgpp Synthetase From Clostridium Difficile, Astha Pokhrel, Asia Poudel, Erin B. Purcell

Chemistry & Biochemistry Faculty Publications

Kinase and pyrophosphokinase enzymes transfer the gamma phosphate or the beta-gamma pyrophosphate moiety from nucleotide triphosphate precursors to substrates to create phosphorylated products. The use of γ-³²-P labeled NTP precursors allows simultaneous monitoring of substrate utilization and product formation by radiography. Thin layer chromatography (TLC) on cellulose plates allows rapid separation and sensitive quantification of substrate and product. We present a method for utilizing the thin-layer chromatography to assay the pyrophosphokinase activity of a purified (p)ppGpp synthetase. This method has previously been used to characterize the activity of cyclic nucleotide and dinucleotide synthetases and is broadly suitable for …

A Numerical Study On Surface Wave Evolution Over Viscoelastic Mud, Elham Sharifineyestani, Navid Tahvildari

Civil & Environmental Engineering Faculty Publications

A numerical modeling approach is applied to investigate the combined effect of wave-current-mud on the evolution of nonlinear waves. A frequency-domain phase-resolving wave-current model that solves nonlinear wave-wave interactions is used to solve wave evolution. A comparison between the results of numerical wave model and the laboratory experiments confirms the accuracy of the numerical model. The model is then applied to consider the effect of mud properties on nonlinear surface wave evolution. It is shown that resonance effect in viscoelastic mud creates a complex frequency-dependent dissipation pattern. In fact, due to the resonance effect, higher surface wave frequencies can experience …

Driving Factors On Runoff Change In The North Semiarid Rapidly Urbanization Watershed, Yong Bai, Rui-Zhong Gao, Xi-Xi Wang, Wei-Na Wang

Civil & Environmental Engineering Faculty Publications

The hydrological process of a watershed influences a lot on the local socioeconomic development. The analysis of runoff change caused by the rapid urbanization on the watershed is of important significance in the management and protection of the local water resource. In this study, based on the land use information from remotely sensed images, the hydrometeorological observation data and the social economy data from 1997 to 2015, the relationship between the influencing factors and the runoff trend in Wulanmulun River watershed was analyzed at different time scale using the improved Mann-Kendall Test and PCA (principal component analysis) method. The results …

A Constitutive Model For Entangled Polydisperse Linear Flexible Polymers With Entanglement Dynamics And A Configuration Dependent Friction Coefficient. Part I: Model Derivation, David W. Mead, Saman Monjezi, Joontaek Park

Chemical and Biochemical Engineering Faculty Research & Creative Works

A new polydisperse "toy" constitutive model is derived and developed from fundamental principles and ideas governing the nonlinear rheology of linear flexible polymers [Mead et al., J. Rheol. 59, 335-363 (2015)]. Specifically, the new model is comprised of four fundamental pieces. First, the model contains a simple differential description of the entanglement dynamics of discrete entanglement pairs. Second, the model contains a differential description of the ij entanglement pair orientation tensor dynamics. Third, following a similar development by Mead and Mishler [J. Non-Newtonian Fluid Mech. 197, 61-79 and 80-90 (2013).], a diluted stretch tube is constructed to describe the relative …

A Constitutive Model For Entangled Polydisperse Linear Flexible Polymers With Entanglement Dynamics And A Configuration Dependent Friction Coefficient. Part Ii. Modeling "Shear Modification" Following Cessation Of Fast Shear Flows, David W. Mead, Saman Monjezi, Joontaek Park

Chemical and Biochemical Engineering Faculty Research & Creative Works

The polydisperse Mead-Park (MP) "toy" molecular constitutive model developed in Paper I [Mead et al., J. Rheol. 62, 121-134 (2017)] as well as our previously published work [e.g., J. Rheol. 59, 335-363 (2015)] is used in the "forward" direction to study model polydisperse melts of entangled linear flexible polymers in severe, fast shear flows. The properties of our new model are elucidated by way of numerical simulation of a representative model polydisperse polymer melt in step shear rate and interrupted shear flow. In particular, we demonstrate how the MP model simulates the individual molecular weight distribution (MWD) component dynamics as …

Comparison Of Artificial Saliva Vs Saline Solution On Rate Of Suture Degradation In Oropharyngeal Surgery, Jenna W. Briddell, Luke Riexinger, Jove Graham, Donna M. Ebenstein

Faculty Journal Articles

IMPORTANCE Absorbable sutures are designed to degrade and lose strength over time. Manufacturers warn that exposure to various body fluids can change the estimated degradation rate of these sutures, but few studies have been conducted to quantify the degree of change associated with saliva.

OBJECTIVE To quantify the association of increased loss of strength of sutures over time after exposure to artificial saliva (hereinafter referred to as “saliva”).

DESIGN, SETTING, AND PARTICIPANTS This experimental in vitro study was conducted at Bucknell University (Lewisburg, Pennsylvania) from June 19, 2015, to July 4, 2015. No participants were involved. The loss of strength …

Special Issue: Neutrosophic Information Theory And Applications, Florentin Smarandache, Jun Ye

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophiclogic,symboliclogic,set,probability,statistics,etc.,are,respectively,generalizations of fuzzy and intuitionistic fuzzy logic and set, classical and imprecise probability, classical statistics, and so on. Neutrosophic logic, symbol logic, and set are gaining significant attention in solving many real-life problems that involve uncertainty, impreciseness, vagueness, incompleteness, inconsistency, and indeterminacy. A number of new neutrosophic theories have been proposed and have been applied in computational intelligence, multiple-attribute decision making, image processing, medical diagnosis, fault diagnosis, optimization design, etc. This Special Issue gathers original research papers that report on the state of the art, as well as on recent advancements in neutrosophic information theory in soft computing, artificial intelligence, …

Application For Position And Load Reference Generation Of A Simulated Mechatronic Chain, Florentin Smarandache, V. Vladareanu, S.B. Cononovici, M. Migdalovici, H. Wang, Y. Feng

Branch Mathematics and Statistics Faculty and Staff Publications

The paper presents the position and load reference generation for a motor stand simulating a mechatronic chain, in this case a three degree of freedom robot leg. The task is accomplished using three PLC controlled motors in position as the robot joint actuators coupled with three controlled in torque, simulating the load at each simulation time-step. The paper briefly discusses the mathematical model and presents the visual interface used in the simulation, which is then to be further integrated into a virtual environment robot control application.

Neutrosophic Computing With Sympy (Computación Neutrosófica Mediante Sympy ), Maykel Leyva-Vazquez, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

In this article the concept of neutrosophic number is presented. Jupyter through Google Colaboratory is introduced for calculations. The Sympy library is used to perform the process of neutrosophic computation. Systems of linear neutrosóficas equations are solved by means of the symbolic computation in python. A case study was developed for the determination of vehicular traffic with indeterminacy. As future works are the development of new applications in different areas of engineering and science.

Fundamentals Of Neutrosophic Logic And Sets And Their Role In Artificial Intelligence (Fundamentos De La Lógica Y Los Conjuntos Neutrosóficos Y Su Papel En La Inteligencia Artificial ), Florentin Smarandache, Maykel Leyva-Vazquez

Branch Mathematics and Statistics Faculty and Staff Publications

Neutrosophy is a new branch of philosophy which studies the origin, nature and scope of neutralities. This has formed the basis for a series of mathematical theories that generalize the classical and fuzzy theories such as the neutrosophic sets and the neutrosophic logic. In the paper, the fundamental concepts related to neutrosophy and its antecedents are presented. Additionally, fundamental concepts of artificial intelligence will be defined and how neutrosophy has come to strengthen this discipline.

Modelo De Recomendación Basado En Conocimiento Y Números Svn, Maykel Leyva-Vazquez, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

Recommendation models are useful in the decision-making process that allow the user a set of options that are expected to meet their expectations. Recommendation models are useful in the decision-making process that offer the user a set of options that are expected to meet their SVN expectations to express linguistic terms.

Neutrosophic Computing And Machine Learning, Vol. 1, Florentin Smarandache, Maikel Leyva-Vázquez

Branch Mathematics and Statistics Faculty and Staff Publications

La neutrosofía es una nueva rama de la filosofía la cual estudia el origen, naturaleza y alcance de las neutralidades, así como sus interacciones con diferentes espectros ideacionales: (A) es una idea, proposición, teoría, evento, concepto o entidad; anti (A) es el opuesto de (A); y (neut-A) significa ni (A) ni anti (A), es decir, la neutralidad entre los dos extremos. Etimológicamente neutron-sofía [Frances neutre < Latin neuter, neutral, y griego sophia, conocimiento] significa conocimiento de los pensamiento neutrales y comenzó en 1995. Su teoría fundamental afirma que toda idea < A > tiende a ser neutralizada, disminuida, balaceada por las ideas (no solo como Hegel planteó)- como un estado de equilibrio.

Plasma Medicine: A Brief Introduction, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

This mini review is to introduce the readers of Plasma to the field of plasma medicine. This is a multidisciplinary field of research at the intersection of physics, engineering, biology and medicine. Plasma medicine is only about two decades old, but the research community active in this emerging field has grown tremendously in the last few years. Today, research is being conducted on a number of applications including wound healing and cancer treatment. Although a lot of knowledge has been created and our understanding of the fundamental mechanisms that play important roles in the interaction between low temperature plasma and …

Novel Contact Materials For Improved Performance Cdte Solar Cells, Angus Rocket, Robert Collins, Sylvain Marsillac

Electrical & Computer Engineering Faculty Publications

This program has explored a number of novel materials for contacts to CdTe solar cells in order to reduce the back contact Schottky barrier to zero and produce an ohmic contact. The project tested a wide range of potential contact materials including TiN, ZrN, CuInSe₂:N, a-Si:H and alloys with C, and FeS₂. Improved contacts were achieved with FeS₂. As part of understanding the operation of the devices and controlling the deposition processes, a number of other important results were obtained. In the process of this project and following its conclusion it led to research …

New Dimensions For A Challenging Security Environment: Growing Exposure To Critical Space Infrastructure Disruption Risk, Adrian V. Gheorghe, Alexandru Georgescu, Olga Bucovetchi, Marilena Lazăr, Cezar Scarlat

Engineering Management & Systems Engineering Faculty Publications

Space systems have become a key enabler for a wide variety of applications that are vital to the functioning of advanced societies. The trend is one of quantitative and qualitative increase of this dependence, so much so that space systems have been described as a new example of critical infrastructure. This article argues that the existence of critical space infrastructures implies the emergence of a new category of disasters related to disruption risks. We inventory those risks and make policy recommendations for what is, ultimately, a resilience governance issue.

Engineers' Motivation To Influence Public Decision Making: A Grounded Theory Approach, Sarah Bouazzaoui, Charles B. Daniels

Engineering Management & Systems Engineering Faculty Publications

In the United States of America, public policies and public decision making associated with the engineering field are set by individuals who does not possess expertise and knowledge to carry out these tasks [1]. Most of decision makers are lawyers and social scientists, not engineers [2]. The purpose of this paper is to analyze the various factors which either encourage or inhibit engineers from influencing and participating in public policy. In this study, a grounded theory approach will be followed, data will be collected using semi-structured interviews and analyzed to develop a theory of research direct toward increasing the motivation …

A Framework For Miniaturized Mechanical Characterization Of Tensile, Creep, And Fatigue Properties Of Slm Alloys, Jonathan Torres-Caceres

Electronic Theses and Dissertations

With the heightened design complexity that may be achieved through additive manufacturing (AM) comes an equally complex set of distinct material characteristics. To properly characterize new materials for use in selective laser melting (SLM), extensive analysis is necessary. Traditional testing techniques, however, can be prohibitive in time and cost incurred. The small punch test (SPT) has been developed for such purposes, where material is scarce or costly. Although lacking standardization, SPT has been successfully employed with various materials to assess material properties such as the yield and ultimate strength and verified by traditional testing results. With the accompaniment of numerical …

Multi-Scale Fluid-Structure Interaction Model Analysis Of Patient-Specific Geometry For Optimization Of Lvad Outflow Graft Implantation: An Investigation Aimed At Reducing Stroke Risk, Ray Prather

Electronic Theses and Dissertations

A Left Ventricular Assist Device (LVAD), is a mechanical pump capable of providing circulatory myocardium relief when used as bridge-to-transplantation by reducing the workload of a failing heart, with the additional bonus of allowing for cardiac recovery when used as destination therapy. The newer generations of continuous flow VADs are essentially axial or radial flow pumps, and while these devices are capable their efficiency depends upon fluid composition and flow field patterns. The most devastating complication of VAD therapy is caused by embolization of thrombi formed within the LVAD or inside the heart into the brain leading to stroke. Anticoagulation …

Inspection Process Flow Development For A Warehouse, Pahalawaththage Perera

All Graduate Theses, Dissertations, and Other Capstone Projects

The project is based on a medical device outsourcing company in the US. In 2018 the company added a 44,000 sq ft new warehouse. With the scales of growth and market competition, it has come to a need to optimize production capacity to achieve 98% monthly on time delivery target. Optimizing production capacity comes with efficiently managing operations that impact overall product lead time. A primary factor that impacts the overall product lead time is production preparation time. Production preparation time is impacted by lead times of 3 operations managed by the new warehouse - Receiving Inspection, Incoming Inspection, and …

Effects Of Air-Fuel Ratio And Operating Conditions On Particle Emissions From A Small Diesel Engine, Odinmma John-Paul Ofili

Master’s Theses

Automotive engineers typically increase the air-fuel ratio (AFR) of an engine to control the amount of smoke emitted, but it not quite known how this process affects particulate number (PN). In the work presented, AFR was independently varied to study its effects on PN. It was found that increasing the AFR reduced the concentrations of larger particles from 10⁸ #/cm³ to 10⁶ #/cm³ which is an effect observable as a reduction in smoke. However, the same increases in AFR only resulted in an energy specific PN change from 10¹⁵ #/kWh to 10¹⁴ #/kWh. The …

Dynamics Of A Circular Cylinder In Close Proximity To A Wall, Yargo Teixeira Gomes De Melo

Master’s Theses

The effect of wall proximity on the mechanism of flow-induced vibration of a circular cylinder mounted in a wind tunnel and free to vibrate with two degrees-of-freedom near a rigid plane boundary were examined at a Reynolds number of 1.86 x 10⁵. Hot-wire anemometry and cylinder-mounted accelerometers were used to characterize the flow-induced vibration of the cylinder. In the near wall region (gap ratios, G/D< 0.4) the system was found to exhibit symptoms of movement-induced vibration resulting from the push-and-draw effect of the cylinder pushing into and out of the fluid immediately upstream and downstream of the cylinder. The variation of the width of the separated wake region with the cylinder motion produces a force in phase with the cylinder velocity, resulting in excitation of the cylinder motion. For G/D > 1.0, the alternate shedding of vortices (the Kármán vortex street) produces a fluctuating lift on the body. The lift force also has an associated drag fluctuation at twice the vortex shedding frequency For …

Experimental Study Of Hydraulic Conductivity Of A Soil-Bentonite Cutoff Wall, Landon Crawford Barlow

Master’s Theses

Soil-bentonite (SB) cutoff walls are commonly employed in the US to control groundwater flow and subsurface contaminant migration. In these applications, both the short-term (as built) integrity of the barrier and the potential for degradation in the integrity of the barrier over time are of critical importance. Although many laboratory studies have been conducted to investigate the performance of SB cutoff walls as hydraulic barriers and the various factors affecting this performance, field investigations are scarce. With support from the National Science Foundation, a 200 m long, 7 m deep, and 0.9 m wide SB cutoff wall has been designed, …

A Degradation Function Consistent With Cocks–Ashby Porosity Kinetics, John A. Moore

Mechanical Engineering Faculty Research and Publications

The load carrying capacity of ductile materials degrades as a function of porosity, stress state and strain-rate. The effect of these variables on porosity kinetics is captured by the Cocks–Ashby model; however, the Cocks–Ashby model does not account for material degradation directly. This work uses a yield criteria to form a degradation function that is consistent with Cocks–Ashby porosity kinetics and is a function of porosity, stress state and strain-rate dependence. Approximations of this degradation function for pure hydrostatic stress states are also explored.