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Articles 1 - 30 of 293

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

Feasibility Of Electric Field Assisted Clogging Reduction In Cold Gas Spraying Nozzle, Hendric Tronsson Jun 2020

Feasibility Of Electric Field Assisted Clogging Reduction In Cold Gas Spraying Nozzle, Hendric Tronsson

ENGS 88 Honors Thesis (AB Students)

The relatively novel cold spraying process expands its range of applications constantly. In order to continue this trend, this process still has various hurdles that need to be overcome such as clogging. Clogging within the cold gas spraying process causes porous coatings with less material properties and lower durability; a solution is needed in order to reduce the clogging and so expand the cold gas spraying applications. This study aimed to explore the feasibility of using an electric field to reduce clogging. To do so a simplified channel was used to simulate charged particle trajectory shifts under the influence of ...


Similarity Evaluation Of Topography Measurement Results By Different Optical Metrology Technologies For Additive Manufactured Parts, Yi Zheng, Xiao Zhang, Shaodong Wang, Qing Li, Hantang Qin, Beiwen Li Mar 2020

Similarity Evaluation Of Topography Measurement Results By Different Optical Metrology Technologies For Additive Manufactured Parts, Yi Zheng, Xiao Zhang, Shaodong Wang, Qing Li, Hantang Qin, Beiwen Li

Industrial and Manufacturing Systems Engineering Publications

The surface topographic measurements can be used by the additive manufacturing (AM) industry for in-situ quality inspection. However, disagreements may arise when we use different technologies to measure the topography of the same sample surface due to noise, sampling or optical properties of the sample surface, which may cause miscommunications or confusions between manufacturers. Thus, proposing methods for rating the similarities to match surface topographic data measured by various optical techniques is of crucial importance. This research investigates similarity evaluation methods for three-dimensional point-cloud topography data acquired by different technologies. Two different optical techniques (focus variation microscopy and structured light ...


The Business Case For Industrial Safety: Revealing The Comprehensive Value Of Ergonomic Investments For Manufacturing Enterprises In Industry 4.0, Shane Stan Oct 2019

The Business Case For Industrial Safety: Revealing The Comprehensive Value Of Ergonomic Investments For Manufacturing Enterprises In Industry 4.0, Shane Stan

Honors Theses, University of Nebraska-Lincoln

How can today’s manufacturing enterprises construct, implement, and optimize modern safety initiatives in a manner that will present maximum return on investment and facilitate enterprise growth? Furthermore, how can these manufacturers assure individual ergonomic investments become part of a larger strategy to facilitate organizational change in safety? This work addresses these questions by placing industrial ergonomics in a business improvement context which comprehensively presents the financial returns and growth opportunities poised by modern safety initiatives. Additionally, to further strengthen the business case for industrial safety, an ergonomic action planning framework is established to guide the creation of holistic safety ...


Coronal Plane Spine Twisting Composes Shape To Adjust The Energy Landscape For Grounded Reorientation, J. Diego Caporale, Benjamin W. Mcinroe, Chenze Ning, Thomas Libby, Robert J. Full, Daniel E. Koditschek Sep 2019

Coronal Plane Spine Twisting Composes Shape To Adjust The Energy Landscape For Grounded Reorientation, J. Diego Caporale, Benjamin W. Mcinroe, Chenze Ning, Thomas Libby, Robert J. Full, Daniel E. Koditschek

Departmental Papers (ESE)

Despite substantial evidence for the crucial role played by an active backbone or spine in animal locomotion, its adoption in legged robots remains limited because the added mechanical complexity and resulting dynamical challenges pose daunting obstacles to characterizing even a partial range of potential performance benefits. This paper takes a next step toward such a characterization by exploring the quasistatic terrestrial self-righting mechanics of a model system with coronal plane spine twisting (CPST). Reduction from a full 3D kinematic model of CPST to a two parameter, two degree of freedom coronal plane representation of body shape affordance predicts a substantial ...


Action Recognition In Manufacturing Assembly Using Multimodal Sensor Fusion, Md. Al-Amin, Wenjin Tao, David Doell, Ravon Lingard, Zhaozheng Yin, Ming-Chuan Leu, Ruwen Qin Aug 2019

Action Recognition In Manufacturing Assembly Using Multimodal Sensor Fusion, Md. Al-Amin, Wenjin Tao, David Doell, Ravon Lingard, Zhaozheng Yin, Ming-Chuan Leu, Ruwen Qin

Computer Science Faculty Research & Creative Works

Production innovations are occurring faster than ever. Manufacturing workers thus need to frequently learn new methods and skills. In fast changing, largely uncertain production systems, manufacturers with the ability to comprehend workers' behavior and assess their operation performance in near real-time will achieve better performance than peers. Action recognition can serve this purpose. Despite that human action recognition has been an active field of study in machine learning, limited work has been done for recognizing worker actions in performing manufacturing tasks that involve complex, intricate operations. Using data captured by one sensor or a single type of sensor to recognize ...


Design And Validation Of A Modular Instrument To Measure Torque And Energy Consumption In Industrial Operations, Mary De La Cruz, Ramiro Gonzalez, Jesus A. Gomez, Atilano Mendoza, Javier A. Ortega Aug 2019

Design And Validation Of A Modular Instrument To Measure Torque And Energy Consumption In Industrial Operations, Mary De La Cruz, Ramiro Gonzalez, Jesus A. Gomez, Atilano Mendoza, Javier A. Ortega

Mechanical Engineering Faculty Publications and Presentations

A modular torque measuring instrument capable of performing tapping torque tests (TTT) according to the ASTM D-5619 standard was designed, developed, and validated. With this new instrument, the performance of different lubricants can be evaluated in terms of frictional torque and energy consumption during tapping processes. This instrument can adapt onto any conventional milling machine or CNC machine and operate under various machining operations such as tapping, drilling, and other processes. To validate the design and performance of this new device, three commercially available lubricants were evaluated. From the three tested conditions, the results showed good repeatability, with consistent results ...


Maquiladoras In Central America: An Analysis Of Workforce Schedule, Productivity And Fatigue., Jose L. Barahona Jul 2019

Maquiladoras In Central America: An Analysis Of Workforce Schedule, Productivity And Fatigue., Jose L. Barahona

Masters Theses & Specialist Projects

Textile factories or Maquiladoras are very abundant and predominant in Central American economies. However, they all do not have the same standardized work schedule or routines. Most of the Maquiladoras only follow schedules and regulations established by the current labor laws without taking into consideration many variables within their organization that could affect their overall performance. As a result, the purpose of the study is to analyze the current working structure of a textile Maquiladora and determine the most suitable schedule that will abide with the current working structure but also increase production levels, employee morale and decrease employee fatigue ...


Evaluation Of An Intelligent Team Tutoring System For A Collaborative Two-Person Problem: Surveillance, Alec Ostrander, Desmond Bonner, Jamiahus Walton, Anna Slavina, Kaitlyn M. Ouverson, Adam Kohl, Stephen Gilbert, Michael Dorneich, Anne Sinatra, Eliot H. Winer Jan 2019

Evaluation Of An Intelligent Team Tutoring System For A Collaborative Two-Person Problem: Surveillance, Alec Ostrander, Desmond Bonner, Jamiahus Walton, Anna Slavina, Kaitlyn M. Ouverson, Adam Kohl, Stephen Gilbert, Michael Dorneich, Anne Sinatra, Eliot H. Winer

Industrial and Manufacturing Systems Engineering Publications

This paper describes the development and evaluation of an Intelligent Team Tutoring System (ITTS) for pairs of learners working collaboratively to monitor an area. In the Surveillance Team Tutor (STT), learners performed a surveillance task in a virtual environment, communicating to track hostile moving soldiers. This collaborative problem solving task required significant communication to achieve the common goal of perfect surveillance. In a pilot evaluation, 16 two-person teams performed the task within one of three feedback conditions (Individual, Team, or None) across four trials each. The STT used a unique approach to filtering feedback so that teams in both individual ...


Application Of Artificial Neural Networks To Assess Student Happiness, Gokhan Egilmez, Nadiye O. Erdil, Omid Mohammadi Arani, Mana Vahid Jan 2019

Application Of Artificial Neural Networks To Assess Student Happiness, Gokhan Egilmez, Nadiye O. Erdil, Omid Mohammadi Arani, Mana Vahid

Mechanical and Industrial Engineering Faculty Publications

The purpose of this study is to develop an analytical assessment approach to identify the main factors that affect graduate students' happiness level. The two methods, multiple linear regression (MLR) and artificial neural networks (ANN), were employed for analytical modelling. A sample of 118 students at a small non-profit private university constituted the survey pool. Various factors including education, school facilities, health, social activities, and family were taken into consideration as a result of literature review in happiness assessment. A total of 32 inputs and one output variables were identified during survey design phase. The following survey conduction, data collection ...


An Energy Profile Model For Fused Deposition Modeling 3d Printing Process, Calvin Hawkins Jan 2019

An Energy Profile Model For Fused Deposition Modeling 3d Printing Process, Calvin Hawkins

ROEU 2018-19

This project develops a strategy to monitor and estimate the energy consumption of fused deposition modeling (FDM) additive manufacturing, which will benefit manufacturers and designers seeking to design and manufacture products with minimal energy consumption.


A Multi-Stage Optimization Model For Flexibility In Engineering Design, Ramin Giahi, Cameron A. Mackenzie, Chao Hu Jan 2019

A Multi-Stage Optimization Model For Flexibility In Engineering Design, Ramin Giahi, Cameron A. Mackenzie, Chao Hu

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Engineered systems often operate in uncertain environments. Understanding different environments under which a system will operate is important in engineering design. Thus, there is a need to design systems with the capability to respond to future changes. This research explores designing a hybrid renewable energy system while taking into account long-range uncertainties of 20 years. The objective is to minimize the expected cost of the hybrid renewable energy system over the next 20 years. A design solution may be flexible, which means that the design can be adapted or modified to meet different scenarios in the future. The value of ...


Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey Nov 2018

Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey

Student Research

Over the last few years, the state of Oklahoma has been looking at ways to reduce expenses to address concerns about a budget deficit. There have been efforts made to reduce expenses due to the use of energy. It has been said, when the lights are on, work is getting done. Running lights is therefore the cost of doing business. Our research examines the question, “is there a way to provide better lighting while operating at a lower cost.” This research examines the current lighting at Southwestern State University, primarily fluorescent lighting (FL), and a cost benefit analysis of switching ...


Evidence Of Problem Exploration In Creative Designs, Jaryn A. Studer, Shanna R. Daly, Seda Mckilligan, Colleen M. Seifert Nov 2018

Evidence Of Problem Exploration In Creative Designs, Jaryn A. Studer, Shanna R. Daly, Seda Mckilligan, Colleen M. Seifert

Industrial Design Publications

Design problems are often presented as structured briefs with detailed constraints and requirements, suggesting a fixed definition. However, past studies have identified the importance of exploring design problems for creative design outcomes. Previous protocol studies of designers has shown that problems can “co-evolve” with the development of solutions during the design process. But to date, little evidence has been provided about howdesigners systematically explore presented problems to create better solutions. In this study, we conducted a qualitative analysis of 252 design problems collected from publically available sources, including award-winning product designs and open-source design competitions. This database offers an independent ...


Statistical Reliability Of Wind Power Scenarios And Stochastic Unit Commitment Cost, Didem Sari, Sarah M. Ryan Nov 2018

Statistical Reliability Of Wind Power Scenarios And Stochastic Unit Commitment Cost, Didem Sari, Sarah M. Ryan

Industrial and Manufacturing Systems Engineering Publications

Probabilistic wind power scenarios constitute a crucial input for stochastic day-ahead unit commitment in power systems with deep penetration of wind generation. To minimize the cost of implemented solutions, the scenario time series of wind power amounts available should accurately represent the stochastic process for available wind power as it is estimated on the day ahead. The high computational demands of stochastic programming motivate a search for ways to evaluate scenarios without extensively simulating the stochastic unit commitment procedure. The statistical reliability of wind power scenario sets can be assessed by approaches extended from ensemble forecast verification. We examine the ...


Evaluating The Effect Of Shear Stress On Graft-To Zwitterionic Polycarboxybetaine Coating Stability Using A Flow Cell, Andrew Belanger, Andre Decarmine, Shaoyi Jiang, Keith Cook, Kagya Amoako Oct 2018

Evaluating The Effect Of Shear Stress On Graft-To Zwitterionic Polycarboxybetaine Coating Stability Using A Flow Cell, Andrew Belanger, Andre Decarmine, Shaoyi Jiang, Keith Cook, Kagya Amoako

Mechanical and Industrial Engineering Faculty Publications

The effect of surface coatings on the performance of antifouling activity under flow can be influenced by the flow/coating interactions. This study evaluates the effect of surface coatings on antifouling activity under different flows for the analyses of coating stability. This was done by exposing DOPA-PCB-300/dopamine coated polydimethylsiloxane (PDMS) to physiological shear stresses using a recirculation system which consisted of dual chamber acrylic flow cells, tygon tubing, flow probe and meter, and perfusion pumps. The effect of shear stress induced by phosphate buffered saline flow on coating stability was characterized with differences in fibrinogen adsorption between control (coated ...


In Vitro Cytocompatibility Of Antibacterial Levels Of Polymer Nitric Oxide Release, Rana Gbyli, Christina Zito, Kagya Amoako Jul 2018

In Vitro Cytocompatibility Of Antibacterial Levels Of Polymer Nitric Oxide Release, Rana Gbyli, Christina Zito, Kagya Amoako

Mechanical and Industrial Engineering Faculty Publications

Although the antibacterial property of nitric oxide (NO) has been well documented in gram positive and gram negative bacteria cultures, its cytotoxic effects are not completely clear. To limit potential in vivo cytotoxicity, our group recently investigated the effects of a range of NO fluxes on S. epidermidis and S. aureus to determine a minimum effective NO level. In this study, we report the antibacterial function of this minimum NO level also on gram negative Pseudomonas aeruginosa as well as its cytocompatibility effects on lung and kidney cells. Standardized bacterial cultures were treated with NO releasing PDMS substrates followed by ...


Factors Influencing Household Solar Adoption In Santiago, Chile, Jeffrey P. Walters, Jessica Kaminsky, Claudio Huepe Jun 2018

Factors Influencing Household Solar Adoption In Santiago, Chile, Jeffrey P. Walters, Jessica Kaminsky, Claudio Huepe

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

In Santiago, Chile, the market conditions are seemingly excellent for the household adoption of photovoltaic (PV) technology, yet the uptake is negligible. To explore this paradox, the authors conducted a Delphi study to solicit the knowledge of a panel of Chilean PV experts. These efforts yielded 26 factors—both motivations and barriers—impacting the diffusion of PV in Santiago. Of the 26, experts were in consensus on the relative importance of 21. The literature suggests that diffusion of PV technologies is influenced by complex technical, economic, and social factors. Similarly, the experts saw influence from financial, environmental, and energy supply ...


Optimizing Design For Resilience For Risk-Averse Firms Using Expected Utility And Value-At-Risk, Ramin Giahi, Cameron A. Mackenzie, Chao Hu May 2018

Optimizing Design For Resilience For Risk-Averse Firms Using Expected Utility And Value-At-Risk, Ramin Giahi, Cameron A. Mackenzie, Chao Hu

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Research Problem •Determine how resilience should be integrated into a firm’s design decisions •Optimize design for a risk-averse firm that incorporates resilience


Online Testing To Assess Performance Of Students In A Large Engineering Class, Vrishtee Rane, Cameron A. Mackenzie May 2018

Online Testing To Assess Performance Of Students In A Large Engineering Class, Vrishtee Rane, Cameron A. Mackenzie

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Fall 2017: Engineering Economic Analysis course •242 students: in-class and distance learning •New assessment procedure: Online testing modules •7 required online testing modules •2 bonus testing modules to earn an A •Semester grades determined completely by number of modules passed •Unlimited number of attempts for each testing module •Randomly chosen questions


Modeling Uncertainty In Rooftop Pv Investment, Anuj Mittal, Cameron A. Mackenzie, Caroline C. Krejci, Taylor B. Elkins May 2018

Modeling Uncertainty In Rooftop Pv Investment, Anuj Mittal, Cameron A. Mackenzie, Caroline C. Krejci, Taylor B. Elkins

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

No abstract provided.


Supply Chain Risk Analysis Using Dynamic Fault Tree, Xue Lei, Cameron A. Mackenzie May 2018

Supply Chain Risk Analysis Using Dynamic Fault Tree, Xue Lei, Cameron A. Mackenzie

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Outline: 1. Motivations 2. Main-backup supply chain 3. Mutual-assistance supply chain 4. Conclusions


Decision Making For Different Types Of Variation In A Manufacturing System, Xue Lei, Cameron A. Mackenzie, Caroline Krejci May 2018

Decision Making For Different Types Of Variation In A Manufacturing System, Xue Lei, Cameron A. Mackenzie, Caroline Krejci

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Common cause variation: Natural part of the process; Acting on process.

Special cause variation: From external sources; searching and mitigating causes.


Design Optimization Under Long-Range Uncertainty, Ramin Giahi, Cameron A. Mackenzie, Chao Hu May 2018

Design Optimization Under Long-Range Uncertainty, Ramin Giahi, Cameron A. Mackenzie, Chao Hu

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Flexibility in engineering system design: •Flexibility in system design and implications for aerospace systems (Saleh et.al 2003) •A flexible and robust approach for preliminary engineering design based on designer's preference (Nahmet.al, 2007) •A real options approach to hybrid electric vehicle architecture design for flexibility (Kang et.al 2016) •Our research: •Simulation optimization •Long range uncertainty •Add flexibility and robustness to design


A Multi-Stage Stochastic Programming For Lot-Sizing And Scheduling Under Demand Uncertainty, Zhengyang Hu, Guiping Hu May 2018

A Multi-Stage Stochastic Programming For Lot-Sizing And Scheduling Under Demand Uncertainty, Zhengyang Hu, Guiping Hu

Industrial and Manufacturing Systems Engineering Publications

A stochastic lot-sizing and scheduling problem with demand uncertainty is studied in this paper. Lot-sizing determines the batch size for each product and scheduling decides the sequence of production. A multi-stage stochastic programming model is developed to minimize overall system costs including production cost, setup cost, inventory cost and backlog cost. We aim to find the optimal production sequence and resource allocation decisions. Demand uncertainty is represented by scenario trees using moment matching technique. Scenario reduction is used to select scenarios with the best representation of original set. A case study based on a manufacturing company has been conducted to ...


Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed Jan 2018

Communication Based Control For Dc Microgrids, Mahmoud S. Saleh, Yusef Esa, Ahmed Mohamed

Publications and Research

Centralized communication-based control is one of the main methods that can be implemented to achieve autonomous advanced energy management capabilities in DC microgrids. However, its major limitation is the fact that communication bandwidth and computation resources are limited in practical applications. This can be often improved by avoiding redundant communications and complex computations. In this paper, an autonomous communication-based hybrid state/event driven control scheme is proposed. This control scheme is hierarchical and heuristic, such that on the primary control level, it encompasses state-driven local controllers, and on the secondary control level, an event-driven MG centralized controller (MGCC) is used ...


Benchmarking Environmental Efficiency Of Ports Using Data Mining And Rdea: The Case Of A U.S. Container Ports, Yong Shin Park, N. Muhammad Aslaam Mohamed Abdul Ghani, Fesseha Gebremikael, Gokhan Egilmez Jan 2018

Benchmarking Environmental Efficiency Of Ports Using Data Mining And Rdea: The Case Of A U.S. Container Ports, Yong Shin Park, N. Muhammad Aslaam Mohamed Abdul Ghani, Fesseha Gebremikael, Gokhan Egilmez

Mechanical and Industrial Engineering Faculty Publications

This study provides step-wise benchmarking practices of each port to enhance the environmental performance using a joint application of the data-mining technique referred to as Kohonen’s self-organizing map (KSOM) and recursive data envelopment analysis (RDEA) to address the limitation of the conventional data envelopment analysis. A sample of 20 container ports in the U.S.A. were selected, and data on input variables (number of quay crane, acres, berth and depth) and output variables (number of calls, throughput and deadweight tonnage, and CO2 emissions) are used for data analysis. Among the selected samples, eight container ports are found to ...


Application Of Bayesian Belief Network For Agile Kanban Backlog Estimation, Eric D. Weflen, Kevin Korniejczuk, Sharon Lau, Steven S. Kryk, Cameron A. Mackenzie, Iris V. Rivero Jan 2018

Application Of Bayesian Belief Network For Agile Kanban Backlog Estimation, Eric D. Weflen, Kevin Korniejczuk, Sharon Lau, Steven S. Kryk, Cameron A. Mackenzie, Iris V. Rivero

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

What is Agile Kanban?

  • Different from Kanban for JIT manufacturing!
  • Visualization of workflow
  • Limit work in process (WIP)


An Investigation On Selected Factors That Cause Variability In Additive Manufacturing, Anusha Velineni, Elif Elçin Günay, Kijung Park, Gül E. Okudan Kremer, Thomas M. Schnieders, Richard T. Stone Jan 2018

An Investigation On Selected Factors That Cause Variability In Additive Manufacturing, Anusha Velineni, Elif Elçin Günay, Kijung Park, Gül E. Okudan Kremer, Thomas M. Schnieders, Richard T. Stone

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Additive manufacturing (AM) brings significant freedom in design, yet it can get hard to produce the same part at identical dimensional tolerances; this is also known as the reproducibility problem. Reproducibility, the ability to produce the same part under similar conditions, is one of the major challenges in AM as reproducibility plays an important role in the replacement of worn-out or damaged parts in an assembly. The objective of this paper is to identify the impacts of two most common factors (i.e., layer thickness and printing speed) on the dimensional accuracy of additively manufactured parts through a designed experiment ...


A Design Framework For Additive Manufacturing Through The Synergistic Use Of Axiomatic Design Theory And Triz, Sarath C. Renjith, Gül E. Okudan Kremer, Kijung Park Jan 2018

A Design Framework For Additive Manufacturing Through The Synergistic Use Of Axiomatic Design Theory And Triz, Sarath C. Renjith, Gül E. Okudan Kremer, Kijung Park

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Additive manufacturing has emerged as an integral part of modern manufacturing because of its unique capabilities for rapid prototyping and the design flexibility. In order to take full advantage of additive manufacturing, Design for Additive Manufacturing (DfAM) has risen to provide design frameworks, methodologies, and a set of guidelines for effective product designs under additive manufacturing. However, the existing DfAM methods have limitations in that most methods rely on either too general or too specific design requirements and parameters for additive manufacturing; an effective design framework that can consider the capabilities and constraints of additive manufacturing at an early design ...


3d Perception-Based Collision-Free Robotic Leaf Probing For Automated Indoor Plant Phenotyping, Yin Bao, Dylan Shah, Lie Tang Jan 2018

3d Perception-Based Collision-Free Robotic Leaf Probing For Automated Indoor Plant Phenotyping, Yin Bao, Dylan Shah, Lie Tang

Agricultural and Biosystems Engineering Publications

Various instrumentation devices for plant physiology study such as spectrometer, chlorophyll fluorimeter, and Raman spectroscopy sensor require accurate placement of their sensor probes toward the leaf surface to meet specific requirements of probe-to-target distance and orientation. In this work, a Kinect V2 sensor, a high-precision 2D laser profilometer, and a six-axis robotic manipulator were used to automate the leaf probing task. The relatively wide field of view and high resolution of Kinect V2 allowed rapid capture of the full 3D environment in front of the robot. The location and size of each plant were estimated by k-means clustering where “k ...