Engineering Commons^™

Heuristic And Exact Algorithms For The Two-Machine Just In Time Job Shop Scheduling Problem, Mohammed Al Salem, Leonardo Bedoya-Valencia, Ghaith Rabadi

Engineering Management & Systems Engineering Faculty Publications

The problem addressed in this paper is the two-machine job shop scheduling problem when the objective is to minimize the total earliness and tardiness from a common due date (CDD) for a set of jobs when their weights equal 1 (unweighted problem). This objective became very significant after the introduction of the Just in Time manufacturing approach. A procedure to determine whether the CDD is restricted or unrestricted is developed and a semirestricted CDD is defined. Algorithms are introduced to find the optimal solution when the CDD is unrestricted and semirestricted. When the CDD is restricted, which is a much …

Panic That Spreads Sociobehavioral Contagion In Pedestrian Evacuations, Terra Elzie, Erika Frydenlund, Andrew J. Collins, R. Michael Robinson

VMASC Publications

Crowds are a part of everyday public life, from stadiums and arenas to school hallways. Occasionally, pushing within the crowd spontaneously escalates to crushing behavior, resulting in injuries and even death. The rarity and unpredictability of these incidents provides few options to collect data for research on the prediction and prevention of hazardous emergent behaviors in crowds. This study takes a close look at the way states of agitation, such as panic, can spread through crowds. Group composition—mainly family groups composed of members with differing mobility levels—plays an important role in the spread of agitation through the crowd, ultimately affecting …

Towards A Systems Theory-Based Curriculum For Complex Systems Governance, Polinpapilinho Katina, Joseph M. Bradley

Engineering Management & Systems Engineering Faculty Publications

The purpose of this paper is to explore challenges associated with the development of a curriculum for an emerging field of Complex System Governance (CSG) that could be used for instruction and teaching leaders, managers, and students interested in increasing their knowledge, skills, and abilities about CSG. CSG has been suggested as a means to (1) expose deep system issues impacting performance, (2) introduce practitioners to new thinking, technologies, tools, and methods to address these issues, and (3) institutionalize capabilities to continuously advance governance. As with all new approaches, a curriculum in an emerging field is an essential element for …

A Flexible Pet-Based Wearable Sensor For Arterial Pulse Waveform Measurement, Dan Wang, Dean Krusienski, Zhili Hao

Mechanical & Aerospace Engineering Faculty Publications

In light of the need of health monitoring, the paper presents a flexible polyethylene terephthalate (PET)-based wearable sensor for arterial pulse waveform measurement. The sensor encompasses a polydimethylsiloxane (PDMS) microstructure embedded with an electrolyte-enabled 5×1 transducer array, which spans 6mm and has a spatial resolution of 1.5mm. A pulse signal exerts a deflection on the microstructure and is recorded as a resistance change by a transducer at the site of the pulse. An untrained individual can easily align the sensor on a targeted artery with a negligible margin and then acquire the arterial pulse waveform continuously and non-invasively. This sensor …

Integrating Cobots In Engineering Technology Education, Ana M. Djuric, Vukica Jovanovic, Tatiana V. Goris, Otilia Popescu

Engineering Technology Faculty Publications

Collaborative robots or CoBots, unlike traditional robots, are safe and flexible enough to work harmoniously with humans. Exploiting the efficiency of automated operations and the flexibility of manual operations in one process can improve productivity and worker job satisfaction. CoBots technology has been experiencing strong growth in different areas such as ground transportation, food-processing industry, car manufacturing, and naval or aeronautical engineering. Current CoBots education and training opportunities are rare or non-existent in university environments. In response to this need, we developed several CoBots modules which will be integrated in the current robotics and mechatronics courses. In this paper we …

Modeling Of Reliability And Performance Assessment Of A Dissimilar Redundancy Actuation System With Failure Monitoring, Wang Shaoping, Cui Xiaoyu, Shi Jian, Mileta M. Tomovic, Jiao Zongxia

Engineering Technology Faculty Publications

Actuation system is a vital system in an aircraft, providing the force necessary to move flight control surfaces. The system has a significant influence on the overall aircraft performance and its safety. In order to further increase already high reliability and safety, Airbus has implemented a dissimilar redundancy actuation system (DRAS) in its aircraft. The DRAS consists of a hydraulic actuation system (HAS) and an electro-hydrostatic actuation system (EHAS), in which the HAS utilizes a hydraulic source (HS) to move the control surface and the EHAS utilizes an electrical supply (ES) to provide the motion force. This paper focuses on …

The Role Of 'Metasystem' In Engineering A System Of Systems, Polinpapilinho F. Katina, Charles B. Keating, Joseph M. Bradley

Engineering Management & Systems Engineering Faculty Publications

Fundamentally, a system of systems is characterized by operational independence, managerial independence, evolutionary development, emergent behavior, and geographical distribution. However, value-wise, a system of systems should provide greater capability beyond that which individual systems can provide. Enabling this greater capability has to be purposely designed for and managed. In this paper, we argue that this is the primary role of the metasystem structure and its execution. A metasystem is a governing structure that provides coordination and integration of multiple systems, brought together to achieve overarching missions and functions beyond those of the constituent systems. This paper articulates the differences between …

Integrating A Simple Traffic Incident Model For Rapid Evacuation Analysis, Andrew J. Collins, R. Michael Robinson, Peter Foytik, Craig Jordan, Barry C. Ezell

VMASC Publications

Road transportation networks are a segment of society's critical infrastructure particularly susceptible to service disruptions. Traffic incidents disrupt road networks by producing blockages and increasing travel times, creating significant impacts during emergency events such as evacuations. For this reason, it is extremely important to incorporate traffic incidents in evacuation planning models. Emergency managers and decision makers need tools that enable rapid assessment of multiple, varied scenarios. Many evacuation simulations require high-fidelity data input making them impractical for rapid deployment by practitioners. Since there is such variation in evacuation types and the method of disruption, evacuation models do not require the …

Comparing High School Students' And Adults' Perceptions Of Technology, Henry L. (Hal) Harrison Ii, Philip A. Reed

STEMPS Faculty Publications

This study compared high school student’s perceptions of technology and technological literacy to those perceptions of the general public. Additionally, individual student groups were compared statistically to determine significant differences between the groups. The ITEA/Gallup Poll instrument was used to survey high school student’s perceptions of technology in the study. The student population in question consisted of three subgroups: students enrolled in a standards-based technology education courses, students enrolled in a Project Lead the Way (PLTW) Principles of Engineering pre-engineering course, and students enrolled in a general education course (language arts, mathematics, or science). In addition, each student group’s perceptions …

Use Of Eportfolio As Integrated Learning Strategy In Computer Integrated Manufacturing Online Course, V. M. Jovanovic, Megan Mize, Rochelle Rodrigo, Alok K. Verma

Engineering Technology Faculty Publications

Integrated learning is a vital strategy for engaging undergraduate Engineering students in the higher levels of learning, as it encourages students to reflect on their learning processes and draw connections between course-work and "real-world" experiences. Specifically, ePortfolios encourage novice engineers to consider their learning processes over time, drawing connections between coursework and their intended profession, as well as cultivating an online identity that supports their efforts to pursue a career in Engineering. The use of ePortfolios is one method for fostering integrative learning, focusing on the application of digital communication and assessment and awareness of self-competence. By training students to …

Period Batch Control - A Production Planning System Applied To Virtual Manufacturing Cells, Z. Tesic, B. Stevanaov, V. Jovanovic, M. Tomic, C. Kafol

Engineering Technology Faculty Publications

Period Batch Control (PBC) system has been known for its implementation with the classical group technology (GT) cells, and it has been known for its simplicity. The main production planning decisions concern the choice of the period length and the stage number and contents. Also, in order to better integrate the production planning with the application of GT cells at the shop floor, the concept of virtual manufacturing cells has been applied. Since virtual cells configurations are changing periodically, a model for implementing the PBC system into virtual manufacturing cells environment is developed. The model enables alignment of the PBC …

Competencies Related To Marine Mechatronics Education, Vukica M. Jovanovic, Petros J. Katsioloudis, Mileta Tomovic, Thomas B. Stout

Engineering Technology Faculty Publications

Recent changes in the needs of the military have caused the U.S. Navy to spend more time out to sea. Longer deployments limit the time available for performing maintenance and for training their technicians. The Navy is also steadily reducing the number of sailors manning each vessel, therefore requiring more automated systems to keep the ships at sea and in total readiness. To meet this need, industrial automation systems are being investigated as replacements and upgrades for the military systems that have been used for years in warship designs. This will require ship repair partners, both military and civilian, to …

Pilot Programs For Veterans Transition To Engineering Fields, Vukica M. Jovanovic, Anthony W. Dean, Carol L. Considine, Karina Arcaute, Petros Katsioloudis, Mileta Tomovic, Thomas B. Stout, Connor Schwalm, Jennifer G. Michaeli, Yuzhong Shen

Engineering Technology Faculty Publications

Veterans, through their active service, frequently receive training in highly skilled technical areas. However, they may lack a theoretical background in underlying engineering principles. They also need additional support with the transition from a highly structured military environment to an environment with more ambiguous time constraints and different sorts of responsibilities. Moreover they are facing challenges which are specific for their student population. Therefore, enabling multiple mechanisms which would support them and provide them necessary guidance are especially important at universities with large veteran populations such as at Old Dominion University in Norfolk, Virginia. Hence, there is a need for …

An Asynchronous Course/Laboratory Development For Automation Controls, Cheng Y. Lin, Mileta Tomovic, Vukica M. Jovanovic

Engineering Technology Faculty Publications

The development of asynchronous courses is to help students who are restricted by work requirements, family responsibilities, geographical distance, disabilities, and combination of these factors. It also provides flexibilities to on-campus students. In this paper, the framework structure of an asynchronous course and laboratory development for an automation control is presented. The challenge in this development is to implement the hands-on laboratory experience to those distance learning students who may not be able to access the real equipment. Results of the implementation including opinion feedbacks and grade distributions show that students welcome the format of this development.

Teaching Robot Kinematics For Engineering Technology Students Using A Created Three-Dimensional Robot And Camera, Cheng Y. Lin, Yuzhong Shen

Engineering Technology Faculty Publications

Teaching robot kinematics is important to engineering technology students in the robot automation. The study can help students not only in the coordinate transformation principles from a joint to its following joint in a robot, but also in relating the coordinate systems between a robot and a machine vision system. While students can utilize math software to compute robot kinematic transformations, they have problems verifying their answers. In this paper, a three dimensional vertically articulated robot is created to help students visualize the location and orientation of the end effector. Students can check their robot kinematic answers based on the …

A Pilot Program For The Recruitment And Education Of Navy Veterans Based On System-Level Technical Expertise And Leadership Maturation Developed During Service, Anthony W. Dean, Connor Schwalm, Patrick S. Heaney, Linda Vahala, Yuzhong Shen, Jennifer G. Michaeli

Engineering Technology Faculty Publications

The project, Stern2STEM, aims to advance STEM (Science, Technology, Engineering, and Mathematics) education through the preparation of student veterans to pursue baccalaureate STEM degrees and support the re-employment of these veterans into the Department of Defense (DoD) and the wider defense support industry. The program builds on the training that veterans have received in highly skilled technical areas, both in the classroom and “on-the-job”, to develop system level expertise in their respective technical disciplines. Key components of the program include: (1) establishing a mechanism for outreach and recruitment; (2) providing leveling, tutoring, mentoring, and support for students; (3) teaching …

Quantitative Assessment Of Secondary Flows Of Single-Phase Fluid Through Pipe Bends, Z. Kaldy, O. Ayala

Engineering Technology Faculty Publications

Single-phase fluid flow was simulated passing through various three dimensional pipe elbows. The simulations varied by Reynolds number, curvature ratios, and sweep angles and were all conducted using the k-e model available in COMSOL Multiphysics 5.1. The intent of this research was to qualitatively assess the flow characteristics under several different conditions. Many similarities were seen especially when comparing curvature ratios, the vorticity location for the turbulent cases show near identical behavior at the elbow midsection. One of the variables quantified in this paper is the maximum secondary velocity module which shows increasing values until the midsection of the elbow.

Secondary Flow Of Liquid-Liquid Two-Phase Fluids In A Pipe Bend, M. Ayala, P. Santos, G. Hamester, O. Ayala

Engineering Technology Faculty Publications

A simulated study of oil and water in 90 degree bend was carried on COMSOL 5.1 to characterize flow pattern and analyze the secondary flow. The Euler-Euler k-e Reynolds Averaged Navier-Stokes model was used to represent the fluid motion. Changes in the Reynolds number, curvature ratio and direction of gravity were made to evaluate the effects in the intensity of the secondary flow. In the end, it was possible to see that the bend direction does not affect the formation of secondary flow for Reynolds above 100,000. It appears that the fluid behavior on the pipe bend is strongly related …

Applications Of Digital Manufacturing In Manufacturing Process Support, Vukica Jovanovic, Mihael Debevec, Niko Herakovic, Alok Verma, Mileta Tomovic

Engineering Technology Faculty Publications

In this study, the authors developed three new approaches and models for improvements related to manufacturing processes. The main focus was on planning in a digital environment before the actual manufacturing process is carried out. The first approach is digital manufacturing, which gives affords the opportunity for performing an entire manufacturing process in a virtual environment. In this way, engineers virtually define, plan, create, monitor, and control all production processes. The planning phase can be done simultaneously, while other manufacturing processes are already in place. In this way, processes can continue with no interruption. Various product lifecycle management tools have …

The Reconfigurable Machinery Efficient Workspace Analysis Based On The Twist Angles, Ana M. Djuric, Vukica Jovanovic, Mirjana Filipovic, Ljubinko Kevac

Engineering Technology Faculty Publications

A novel methodology for the calculation, visualisation and analysis of the Reconfigurable Machinery Efficient Workspace (RMEW), based on the twist angles, is presented in this paper. The machinery's kinematic parameters are used for calculating the workspace, while the efficient workspace is associated with the machinery's path and includes the end-effector position and orientation. To analyse and visualise many different machinery efficient workspaces at the same time, the calculation is based on the previously developed and validated complex reconfigurable machinery's kinematic structure named n-DOF Global Kinematic Model (n-GKM). An industrial robot is used as an example to demonstrate …

Impairment Of Continuous Insulin Delivery Therapy And Analysis From Graeco-Latin Square Design Model, Norou Diawara, Ayodeji Demuren, Eric Gyuricsko

Mathematics & Statistics Faculty Publications

The desire to deliver measured amount of insulin continuously to patients with type I diabetes, for glycemic control, has attracted a lot of attention. Continuous subcutaneous insulin infusion has seen some success in recent years. However, occlusion of insulin delivery may prevent the patient from receiving the prescribed dosage, with adverse consequence. An in vitro study of insulin delivery is performed, using different insulin pumps, insulin analogs and operating conditions. The aim is to identify incidences of occlusion due to bubble formation in the infusion line. A detailed statistical analysis was performed on the data collected to determine any significant …

Disaster Preparedness And Response: A Survey Of U.S. Dental Hygienists, Brenda T. Bradshaw, Ann P. Bruhn, Tara L. Newcomb, Bridget T. Giles, Kathryn Simms

Dental Hygiene Faculty Publications

Purpose: The purpose of this study was to assess dental hygienists’ interests, current involvement, formal education, views, comfort levels, and intentions for involvement with disaster preparedness and response.

Methods: Dental hygienists (n=400) were asked to respond to a 21-item online survey. Data was analyzed using descriptive statistics, chi-square goodness-of-fit tests, and a paired-samples t-test. Common themes were identified and categorized from open-ended questions.

Results: A response rate of 84% (n=334) was obtained. Most respondents (97%) reported no involvement with disaster preparedness and response; however, a majority (86%) reported interest. Of those who indicated an interest in disaster preparedness and response, …

Regression Analysis Of Pem Fuel Cell Transient Response, Russell L. Edwards, Ayodeji Demuren

Mechanical & Aerospace Engineering Faculty Publications

To develop operating strategies in polymer electrolyte membrane (PEM) fuel cell-powered applications, precise computationally efficient models of the fuel cell stack voltage are required. Models are needed for all operating conditions, including transients. In this work, transient evolutions of voltage, in response to load changes, are modeled with a sum of three exponential decay functions. Amplitude factors are correlated to steady-state operating data (temperature, humidity, average current, resistance, and voltage). The obtained time constants reflect known processes of the membrane heat/water transport. These model parameters can form the basis for the prediction of voltage overshoot/undershoot used in computational-based control systems, …

An Efficient Solution To The Mixed Shop Scheduling Problem Using A Modified Genetic Algorithm, V. Nguyen, H. P. Bao

Mechanical & Aerospace Engineering Faculty Publications

The mixed job shop scheduling problem is one in which some jobs have fixed machine orders and other jobs may be processed in arbitrary orders. In past literature, optimal solutions have been proposed based on adaptations of classical solutions such as by Johnson, Thompson and Giffler among many others, by pseudopolynomial algorithms, by simulation, and by Genetic Algorithms (GA). GA based solutions have been proposed for flexible Job shops. This paper proposes a GA algorithm for the mixed job shop scheduling problem. The paper starts with an analysis of the characteristics of the so-called mixed shop problem. Based on those …

Intracellular Ros Mediates Gas Plasma-Facilitated Cellular Transfection In 2d And 3d Cultures, Dehui Xu, Biqing Wang, Yujing Xu, Zeyu Chen, Qinjie Cui, Yanjie Yang, Hailan Chen, Michael G. Kong

Bioelectrics Publications

This study reports the potential of cold atmospheric plasma (CAP) as a versatile tool for delivering oligonucleotides into mammalian cells. Compared to lipofection and electroporation methods, plasma transfection showed a better uptake efficiency and less cell death in the transfection of oligonucleotides. We demonstrated that the level of extracellular aqueous reactive oxygen species (ROS) produced by gas plasma is correlated with the uptake efficiency and that this is achieved through an increase of intracellular ROS levels and the resulting increase in cell membrane permeability. This finding was supported by the use of ROS scavengers, which reduced CAP-based uptake efficiency. In …

Embedding Online Based Learning Strategies Into The Engineering Technology Curriculum, Vukica M. Jovanovic, Otilia Popescu, Orlando M. Ayala, Mileta Tomovic, Alok K. Verma

Engineering Technology Faculty Publications

Various blended learning strategies have been implemented at engineering technology programs to facilitate different learning styles and different time constraints given to faculty. Some of these efforts are related to the effective use of online tools such as online course management systems, ePortfolios, narrated presentations, web-based polling systems, tutorials and educational materials posted before the class and asynchronous learning methods. As technology changes, some of the online learning methods are getting more advanced which is enabling more innovative approaches and data compression. Various distance learning programs started with having access to videos of recorded lectures (on VHS tapes, or CDs) …

Machine Vision Identification Of Airport Runways With Visible And Infrared Videos, Andrew J. Moore, Matthew Schubert, Chester Dolph, Glenn Woodell

Electrical & Computer Engineering Faculty Publications

A widely used machine vision pipeline based on the Speeded-Up Robust Features feature detector was applied to the problem of identifying a runway from a universe of known runways, which was constructed using video records of 19 straight-in glidepath approaches to nine runways. The recordings studied included visible, short-wave infrared, and long-wave infrared videos in clear conditions, rain, and fog. Both daytime and nighttime runway approaches were used. High detection specificity (identification of the runway approached and rejection of the other runways in the universe) was observed in all conditions (greater than 90% Bayesian posterior probability). In the visible band, …

Use Of Dynamic Visualizations For Engineering Technology, Industrial Technology, And Science Education Students: Implications On Ability To Correctly Create A Sectional View Sketch, Petros J. Katsioloudis, Daniel Dickerson, Vukica Jovanovic, Mildred V. Jones

Engineering Technology Faculty Publications

Spatial abilities, specifically visualization, play a significant role in the achievement in a wide array of professions including, but not limited to, engineering, technical, mathematical, and scientific professions. However, there is little correlation between the advantages of spatial ability as measured through the creation of a sectional-view sketch between engineering technology, industrial technology, and science education students. A causal-comparative study was selected as a means to perform the comparative analysis of spatial visualization ability. This study was done to determine the existence of statistically significant difference between engineering technology, industrial technology, and science education students’ ability to correctly create a …

Introducing Writing Assignments In Engineering Technology Courses To Enhance Technical Writing Skills And Critical Thinking, Otilia Popescu, Vukica M. Jovanovic

Engineering Technology Faculty Publications

This study was prompted by the university wide initiative to improve students' technical writing skills across-the-curriculum by introducing low stakes writing assignments as early as in their freshman year. Effective written communication skills are important for engineering education, with critical thinking being one of the most important aspects of the learning process at the college level. However, the efforts in required core curriculum English and communication courses are not always further integrated into engineering curriculum. Introducing a technical paper writing assignment in lower division engineering courses had the purpose of helping students to be better prepared for major writing assignments …

Estimated Grass Grazing Removal Rate In A Semiarid Eurasian Steppe Watershed As Influenced By Climate, Xixi Wang, Shohreh Pedram, Tingxi Liu, Ruizhong Gao, Fengling Li, Yanyun Luo

Civil & Environmental Engineering Faculty Publications

Grazing removal rate of grasses needs to be determined for various climate conditions to address eco-environmental concerns (e.g., desertification) related to steppe grassland degradation. The conventional approach, which requires survey data on animal species and heads as well as grass consumption per individual animal, is too costly and time-consuming to be applied at a watershed scale. The objective of this study was to present a new approach that can be used to estimate grazing removal rate with no requirement of animal-related data. The application of this new approach was demonstrated in a Eurasian semiarid typical-steppe watershed for an analysis period …