Engineering Commons^™

Inactivation Of Bacterial Opportunistic Skin Pathogens By Nonthermal Dc-Operated Afterglow Atmospheric Plasma, L. C. Heller, C. M. Edelblute, A. M. Mattson, X. Hao, J. F. Kolb

Bioelectrics Publications

AIMS: Multidrug-resistant opportunistic pathogens are clinically significant and require the development of new antimicrobial methods. In this study, Acinetobacter baumannii, Pseudomonas aeruginosa and Staphylococcus aureus cells were exposed to atmospheric plasma on agar plates and in vitro on porcine skin for the purpose of testing bacterial inactivation.

METHODS AND RESULTS: Microbial inactivation at varying exposure durations was tested using a nonthermal plasma jet generated with a DC voltage from ambient air. The observed reduction in colony forming units was quantified as log₁₀ reductions.

CONCLUSIONS: Direct plasma exposure significantly inactivated seeded bacterial cells by approx. 6 log_{10 …}

Future Critical Issues And Problems Facing Technology And Engineering Education In The Commonwealth Of Virginia, Petros Katsioloudis, Johnny J. Moye

STEMPS Faculty Publications

The purpose of this research was to determine the future critical issues and problems facing the K-12 technology and engineering education profession in the Commonwealth of Virginia. This study was based on the Wicklein nationwide studies (1993a, 2005). Even though this study did not exactly replicate the Wicklein studies--since it was limited to the Commonwealth of Virginia--the method and questions used were identical. The modified Delphi research design was used to draw consensus among technology and engineering education experts in the Commonwealth of Virginia. Seventy-five percent of the participants agreed with one another concerning the top five critical problems and …

A Comparative Analysis Of Preferred Learning And Teaching Styles For Engineering, Industrial, And Technology Education Students And Faculty, Petros Katsioloudis, Todd D. Fantz

STEMPS Faculty Publications

No abstract provided.

A System Dynamics Model For Simulating Ambulatory Health Care Demands, Rafael Diaz, Joshua G. Behr, Mandar Tulpule

VMASC Publications

Introduction: This article demonstrates the utility of the system dynamics approach to model and simulate US demand for ambulatory health care service both for the general population and for specific cohort subpopulations over the 5-year period, from 2003 to 2008. A system dynamics approach that is shown to meaningfully project demand for services has implications for health resource planning and for generating knowledge that is critical to assessing interventions.

Methods: The study uses a cohort-component method in combination with structural modeling to simulate ambulatory health care utilization. Data are drawn from the National Ambulatory Medical Care Survey and the National …

The Value Of Modeling And Simulation Standards, Andrew J. Collins, David Meyr, Solomon Sherfey, Andreas Tolk, Mikel Petty

VMASC Publications

In the current economic climate, there is a requirement to justify all government spending by demonstrating the added-value that the expenditure gives. Modeling and Simulation (M&S) community is not exempted from this rule. This paper focuses on attempts to value standards and demonstrates that even though a myriad of different standards exist in the United States today, no one has "cracked the nut" on determining their value. This does not mean that standards are without value. The paper highlights their importance to our society and human development as a whole. Thus if we cannot give a value to M&S standards, …

Enhanced Killing Effect Of Nanosecond Pulse Electric Fields On Panc1 And Jurkat Cell Lines In The Presence Of Tween 80, Gaurav Basu, Bhargava Subhash Kalluri, Ahmet Can Sabuncu, Christopher J. Osgood, Michael W. Stacey

Bioelectrics Publications

We investigated the effects of nanosecond pulse electric fields (nsPEFs) on Jurkat and PANC1 cells, which are human carcinoma cell lines, in the presence of Tween 80 (T80) at a concentration of 0.18% and demonstarted an enhanced killing effect. We used two biological assays to determine cell viability after exposing cells to nsPEFs in the presence of T80 and observed a significant increase in the killing effect of nsPEFs. We did not see a toxic effect of T80 when cells were exposed to surfactant alone. However, we saw a synergistic effect when cells exposed to T80 were combined with the …

On Critical Infrastructure Interdependency, Polinpapilinho F. Katina, C. Ariel Pinto

Engineering Management & Systems Engineering Faculty Publications

Developing effective protection, mitigation, and recovery measures for critical infrastructure (CI) systems is paramount in the wake of increasing natural and manmade hazards, risks, and threats. Influencing protection, rescue, and recovery measures are interplays (i.e., interdependencies) among infrastructure systems. Understanding interdependencies plays an essential role in minimizing and reducing cascading failures among complex interdependent infrastructure systems. This paper asserts that deployment of protection, mitigation, and recovery solutions can have little effect on infrastructure management if infrastructure operators and policymakers have partial understanding of infrastructure interdependencies. Using narrative research, authors illustrate that effective coordination and response for protection, mitigation, and recovery …

System Of Systems Perspective On Risk: Towards A Unified Concept, C. Ariel Pinto, Michael K. Mcshane, Ipek Bozkurt

Finance Faculty Publications

Many systems and projects that concern systems engineers, engineering managers, and business managers today can be defined as system of systems (SoS), which are described as ambiguous, uncertain and dynamic, among others. In addition to the traditional view on risk identification, analysis and management, the concept of risk should be considered with respect to these systems of systems. The purpose of this paper is to analyse both fundamental concepts and recent publications in system of systems, business and engineering management, as well as risk analysis, modelling, and management for the purpose of better describing the concept of risk with respect …

Identification And Implementation Of Patterns Towards A Model Of Environmental Sustainability, S. Jimmy Gandhi, Santiago Perez, Danial Rushton, Robert Cloutier, Ipek Bozkurt, C. Ariel Pinto

Engineering Management & Systems Engineering Faculty Publications

Much like the Quality Revolution did in the 1980's, corporate sustainability has the potential to drive significant changes in the processes and structure of various organizations in the coming decade. With a rapidly growing global population and an ever increasing global demand for resources (Population-Resource-Center, 2012). Sustainability has emerged as one of the primary challenges that organizations will have to deal with in the 21st century. An increasing realization among business executives that profitability by itself is not enough as a measure of success is also driving the increased adoption of sustainable practices in the corporate world (Lowitt and Grimsley, …

Simulation Visualization Rhetoric And It's Practical Implications, D'An Knowles Ball, Andrew J. Collins

Engineering Management & Systems Engineering Faculty Publications

Modeling and simulation has moved far beyond simple data representation into the world of visual communication over the past 15 years; ultimately, the acceptance of M&S within mainstream science and society will depend on the results that are produced visually. A simulation’s function is of primary importance to its end result, but it cannot be denied that the discipline of M&S now prizes fancy graphics to communicate. Rhetorical methodological decisions have the greatest impact on the end user, and considerations that bring visual rhetoric to modeling and simulation should be examined as a necessity to application. This paper will expose …

Anchoring Of Drifting Spiral And Scroll Waves To Impermeable Inclusions In Excitable Media, Christian W. Zemlin, Arkady M. Pertsov

Bioelectrics Publications

Anchoring of spiral and scroll waves in excitable media has attracted considerable interest in the context of cardiac arrhythmias. Here, by bombarding inclusions with drifting spiral and scroll waves, we explore the forces exerted by inclusions onto an approaching spiral and derive the equations of motion governing spiral dynamics in the vicinity of inclusion. We demonstrate that these forces nonmonotonically depend on distance and can lead to complex behavior: (a) anchoring to small but circumnavigating larger inclusions; (b) chirality-dependent anchoring.

Alignment And Composition Of Laminin-Polycaprolactone Nanofiber Blends Enhance Peripheral Nerve Regeneration, Rebekah A. Neal, Sunil S. Tholpady, Patricia L. Foley, Nathan Swami, Roy C. Ogle, Edward A. Botchwey

Medical Diagnostics & Translational Sciences Faculty Publications

Peripheral nerve transection occurs commonly in traumatic injury, causing deficits distal to the injury site. Conduits for repair currently on the market are hollow tubes; however, they often fail due to slow regeneration over long gaps. To facilitate increased regeneration speed and functional recovery, the ideal conduit should provide biochemically relevant signals and physical guidance cues, thus playing an active role in regeneration. To that end, laminin and lamininpolycaprolactone (PCL) blend nanofibers were fabricated to mimic peripheral nerve basement membrane. In vitro assays established 10% (wt) laminin content is sufficient to retain neurite-promoting effects of laminin. In addition, modified collector …

Fusion Of Visual And Thermal Images Using Genetic Algorithms, Sertan Erkanli, Jiang Li, Ender Oguslu, Shangce Gao (Ed.)

Electrical & Computer Engineering Faculty Publications

No abstract provided.

Real-Time Anomaly Detection In Full Motion Video, Glenn Konowicz,, Jiang Li, Donnie Self (Ed.)

Electrical & Computer Engineering Faculty Publications

Improvement in sensor technology such as charge-coupled devices (CCD) as well as constant incremental improvements in storage space has enabled the recording and storage of video more prevalent and lower cost than ever before. However, the improvements in the ability to capture and store a wide array of video have required additional manpower to translate these raw data sources into useful information. We propose an algorithm for automatically detecting anomalous movement patterns within full motion video thus reducing the amount of human intervention required to make use of these new data sources. The proposed algorithm tracks all of the objects …

A Radar-Enabled Collaborative Sensor Networking Integrating Cots Technology For Surveillance And Tracking, Robert Kozma, Lan Wang, Khan Iftekharuddin, Ernest Mccracken, Muhammad Khan, Khandakar Islam, Sushil R. Bhurtel, R. Murat Demirer

Electrical & Computer Engineering Faculty Publications

The feasibility of using Commercial Off-The-Shelf (COTS) sensor nodes is studied in a distributed network, aiming at dynamic surveillance and tracking of ground targets. Data acquisition by low-cost (<$50 US) miniature low-power radar through a wireless mote is described. We demonstrate the detection, ranging and velocity estimation, classification and tracking capabilities of the mini-radar, and compare results to simulations and manual measurements. Furthermore, we supplement the radar output with other sensor modalities, such as acoustic and vibration sensors. This method provides innovative solutions for detecting, identifying, and tracking vehicles and dismounts over a wide area in noisy conditions. This study presents a step towards distributed intelligent decision support and demonstrates effectiveness of small cheap sensors, which can complement advanced technologies in certain real-life scenarios.

Oxidative Effects Of Nanosecond Pulsed Electric Field Exposure In Cells And Cell-Free Media, Olga N. Pakhomova, Vera A. Khorokhorina, Angela M. Bowman, Raminta Rodaitė-Riševičienė, Gintautas Saulis, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Nanosecond pulsed electric field (nsPEF) is a novel modality for permeabilization of membranous structures and intracellular delivery of xenobiotics. We hypothesized that oxidative effects of nsPEF could be a separate primary mechanism responsible for bioeffects. ROS production in cultured cells and media exposed to 300-ns PEF (1–13 kV/cm) was assessed by oxidation of 2′, 7′-dichlorodihydrofluoresein (H₂DCF), dihidroethidium (DHE), or Amplex Red. When a suspension of H₂DCF-loaded cells was subjected to nsPEF, the yield of fluorescent 2′,7′dichlorofluorescein (DCF) increased proportionally to the pulse number and cell density. DCF emission increased with time after exposure in nsPEF-sensitive Jurkat …

Automation Laboratory Development Focusing On Industrial Hands-On Experience, Simulation Software, And Application Research Projects, Cheng Y. Lin, John R. Hackworth

Engineering Technology Faculty Publications

This paper describes the development of an Automation Control Lab in the Department of Engineering Technology at the University. The lab facility includes pneumatic actuators/sensors, electrical relays/switches, and Programmable Logic Controllers (PLC). The major goal of the development is to help students gain hands-on industrial experience by conducting simple projects during the lecture hours and more advanced projects during the lab hours. Simulation software is also applied to reduce implementation time when developing complicated pneumatic circuits and PLC programs. In addition, three examples of industrial automation projects using PLC from the Technology Application Center (TAC) are also introduced to students …

Cell Permeabilization And Inhibition Of Voltage-Gated Ca²+ And Na+ Channel Currents By Nanosecond Pulsed Electric Fields, Vasyl Nesin, Angela M. Bowman, Shu Xiao, Andrei G. Pakhomov

Bioelectrics Publications

Previous studies have found that nanosecond pulsed electric field (nsPEF) exposure causes long-term permeabilization of the cell plasma membrane. In this study, we utilized the whole-cell patch-clamp method to study the nsPEF effect on currents of voltage-gated (VG) Ca²⁺ and Na⁺ channels (I_Ca and I_Na) in cultured GH3 and NG108 cells. We found that a single 300 or 600 ns pulse at or above 1.5-2 kV/cm caused prolonged inhibition of I_Ca and I_Na. Concurrently, nsPEF increased a non-inactivating leak current (I_leak), presumably due to the formation of nanoelectropores or larger …

Economics, Innovations, Technology, And Engineering Education: The Connections, John M. Ritz, P. Scott Bevins

STEMPS Faculty Publications

Throughout history the success of economies around the world has in large part been influenced by technological growth and innovations. Along with such growth and innovations came higher living standards and an improved quality of life for citizens residing and participating in those economies. However, not all countries were able to grow and develop at the same rate, resulting in considerable differences in economic welfare across populations. As nations around the world address the 21st century, economic growth and prosperity for some nations will depend upon how well their citizens are equipped and motivated to seek new technological discoveries and …

Electrokinetic Flow In Polyelectrolyte–Modified Nanopores, L. H. Yeh, M. Zhang, Shizhi Qian, J. P. Hsu, S. W. Joo

Mechanical & Aerospace Engineering Faculty Publications

No abstract provided.

In Situ And Ex Situ Studies Of Molybdenum Thin Films Deposited By Rf And Dc Magnetron Sputtering As A Back Contact For Cigs Solar Cells, K. P. Aryal, H. Khatri, R. W. Collins, S. Marsillac

Electrical & Computer Engineering Faculty Publications

Molybdenum thin films were deposited by rf and dc magnetron sputtering and their properties analyzed with regards to their potential application as a back contact for CIGS solar cells. It is shown that both types of films tend to transition from tensile to compressive strain when the deposition pressure increases, while the conductivity and the grain size decreas. The nucleation of the films characterized by in situ and real time spectroscopic ellipsometry shows that both films follow a Volmer-Weber growth, with a higher surface roughness and lower deposition rate for the rf deposited films. The electronic relaxation time was then …

Electric-Field-Induced Interfacial Instabilities Of A Soft Elastic Membrane Confined Between Viscous Layers, Mohar Dey, Dipankar Bandyopadhyay, Ashutosh Sharma, Shizhi Qian, Sang Woo Joo

Mechanical & Aerospace Engineering Faculty Publications

We explore the electric-field-induced interfacial instabilities of a trilayer composed of a thin elastic film confined between two viscous layers. A linear stability analysis (LSA) is performed to uncover the growth rate and length scale of the different unstable modes. Application of a normal external electric field on such a configuration can deform the two coupled elastic-viscous interfaces either by an in-phase bending or an antiphase squeezing mode. The bending mode has a long-wave nature, and is present even at a vanishingly small destabilizing field. In contrast, the squeezing mode has finite wave-number characteristics and originates only beyond a threshold …

Microfluidic Separation Of Live And Dead Yeast Cells Using Reservoir-Based Dielectrophoresis, Saurin Patel, Daniel Showers, Pallavi Vedantam, Tzuen-Rong Tzeng, Shizhi Qian, Xiangchun Xuan

Mechanical & Aerospace Engineering Faculty Publications

Separating live and dead cells is critical to the diagnosis of early stage diseases and to the efficacy test of drug screening, etc. This work demonstrates a novel microfluidic approach to dielectrophoretic separation of yeast cells by viability. It exploits the cell dielectrophoresis that is induced by the inherent electric field gradient at the reservoir-microchannel junction to selectively trap dead yeast cells and continuously separate them from live ones right inside the reservoir. This approach is therefore termed reservoir-based dielectrophoresis (rDEP). It has unique advantages as compared to existing dielectrophoretic approaches such as the occupation of zero channel space and …

Heat Transfer Enhancement In A Straight Channel Via A Rotationally Oscillating Adiabatic Cylinder, Ali Beskok, Mehrdad Raisee, Bayram Celik, Bedri Yagiz, Mohsen Cheraghi

Mechanical & Aerospace Engineering Faculty Publications

Heat convection from the uniformly heated walls of a straight channel in presence of a rotationally oscillating cylinder (ROC) is simulated at Re = 100. Heat transfer enhancement due to vortex shedding from the ROC is investigated. Systematic studies are performed to explore the rotation angle and frequency influences on heat transfer by varying the latter in range of the lock-in regime and the former from 0 to 2 π/3. All simulation results are based on the numerical solutions of two-dimensional, unsteady, incompressible Navier-Stokes and energy equations using an h/p type finite element algorithm. Considering time periodicity of the resulting …

Implementation And Assessment Of A Virtual Reality Experiment In The Undergraduate Themo-Fluids Laboratory, Sushil Chaturvedi, Jaewan Yoon, Rick Mckenzie, Petros J. Katsioloudis, Hector M. Garcia, Shuo Ren

Mechanical & Aerospace Engineering Faculty Publications

Results are presented from an NSF supported project that is geared towards advancing the development and use of virtual reality (VR) laboratories, designed to emulate the learning environment of physical laboratories. As part of this project, an experiment in the undergraduate thermo-fluids laboratory course titled "Jet Impact Force" was transformed into a 3-D virtual reality experiment using the widely used MAYA R and VIRTOOLS R software. In order to facilitate students' interactions with the newly created 3-D interactive, immersive and stereoscopic virtual laboratory environment, the human computer interfaces (HCI) were programmed and incorporated in the simulation software. Two immersion levels …

Editorial: International Journal Of Critical Infrastructures, Holly Ann Heine Handley, C. Ariel Pinto, Adrian V. Gheorghe

Engineering Management & Systems Engineering Faculty Publications

(First paragraph) This special issue of the International Journal of Critical Infrastructures is a compilation of the papers presented at the Fourth Annual Conference on Next Generation Infrastructures held in Virginia Beach, Virginia, in November, 2011. This conference was sponsored by Old Dominion University, Norfolk, Virginia, USA and by the Next Generation Infrastructures Foundation, Delft, The Netherlands. The participants travelled from around the globe to converse about ideas that address both concerns for the present and optimism for the future of critical infrastructures. The conference, held in the USA for the first time, provided a platform for vibrant discussions on …

A Human View Model For Socio-Technical Interactions, Holly A. H. Handley, Andreas Tolk

Engineering Management & Systems Engineering Faculty Publications

The Human View was developed as an additional architectural viewpoint to focus on the human part of a system. The Human View can be used to collect and organize data in order to understand how human operators interact and impact the other elements of a system. This framework can also be used to develop a model to describe how humans interact with each other in network enabled systems. These socio-technical interactions form the foundation of the emerging area of Human Interoperability. Human Interoperability strives to understand the relationships required between human operators that impact collaboration across networked environments, including the …

An Analysis Of Factors Affecting The Effective Use Of Knowledge Management In Counter Improvised Explosive Device (C-Ied) Operations, Umit Gencer, Rafael E. Landaeta, Resit Unal, C. Ariel Pinto, Gokay Sursal

Engineering Management & Systems Engineering Faculty Publications

Improvised Explosive Device (IED) is a weapon of choice and is likely to remain a major component of the Global War on Terrorism. It is critical that gaps in knowledge transfer are quickly addressed in order to more effectively equip personnel to counter IED (C-IED) threat. Therefore, the military must analyze the current Knowledge Management (KM) programs in C-IED arena in order to maximize transfer of knowledge derived from experience and skill to staffs and finally to commanders. This study investigates the factors that influence effective use of KM in C-IED operations in the military. The study suggests that effective …

Modeling And Evaluating Role And Team Work Processes Using The Improved Performance Research And Integration Tool, Holly A. H. Handley, Pilar Pazos

Engineering Management & Systems Engineering Faculty Publications

The Human View architecture was designed to capture the human requirements of a system and to answer questions about the interactions between humans and systems. Data captured in the Human View can be used to populate a simulation model to evaluate the performance of the humans interacting in a work process. The work process model can be used to investigate different types of human system analyses, at both the role and team levels, and to identify the appropriate metrics to evaluate the results. This study examined individual role performance using the metrics readily available in the simulation tool, and then …

Factors Impacting Technology Transfer: The Maquiladora Industry In Yucatan, Mexico, Ana Maria Canto, Carlos Blanco, Pilar Pazos

Engineering Management & Systems Engineering Faculty Publications

Technology transfer and knowledge transfer are the building blocks for innovation, efficiency and increased competitiveness. The topic of technology transfer in the context of multinational companies has been the focus of technology management researchers for well over two decades. Developing countries housing twin plans have been exposed to technology transfer from very diverse countries with different approaches to the technology transfer process and different levels of success. This cultural and national diversity adds an additional level of complexity to the technology transfer domain that has been largely unexplored. This paper will explore critical factors that had an impact in successful …