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A New Analytical Evaluation Model For Kanban Controlled Systems With Fork/Join Synchronization Stations, Heedong Kim, Sarah M. Ryan 2019 Iowa State University

A New Analytical Evaluation Model For Kanban Controlled Systems With Fork/Join Synchronization Stations, Heedong Kim, Sarah M. Ryan

Sarah M. Ryan

A nonlinear programming model is developed for analyzing the queuing model of a kanban controlled system with fork/join synchronization stations. The model finds the minimum number of kanbans for a given throughput requirement or the maximum throughput for a given number of kanbans, where servers have different exponential service times. Furthermore, it aids understanding of kanban systems.


Integrated Curriculum To Improve Engineering Problem Solving, John K. Jackman, Sigurdur Olafsson, Frank E. Peters, Sarah M. Ryan 2019 Iowa State University

Integrated Curriculum To Improve Engineering Problem Solving, John K. Jackman, Sigurdur Olafsson, Frank E. Peters, Sarah M. Ryan

Sarah M. Ryan

A series of modules based on realistic problems are being developed for our industrial engineering curriculum. These modules require students to use a variety of information technology skills to access, screen and analyze the data available to them. The modules are also designed to help students build relationships among the courses, which they traditionally treat as isolated bodies of knowledge. Students’ engineering problem solving will also be enhanced by the challenge presented by more realistic open-ended problems that are incorporated into the modules. This paper details the results of the latest module used in a Manufacturing Systems Engineering course.


Applying Alternative Decision-Making Approaches To A Complex Supplier Selection Problem, Paul J. Componation, Michael C. Dorneich, Guiping Hu, Gillian M. Nicholls 2019 Iowa State University

Applying Alternative Decision-Making Approaches To A Complex Supplier Selection Problem, Paul J. Componation, Michael C. Dorneich, Guiping Hu, Gillian M. Nicholls

Michael C. Dorneich

Prior work has been completed on understanding how an organization’s decision-making approach can influence the selection of alternative vendors when setting up a supply chain system. Teams using different decision-making approaches on identical performance data did end with different vendor recommendations. One possible explanation of this result was that the data set on vendor performance was limited to five vendors and four variables; however the decision-making approaches had significantly different cognitive requirements. The team members preferred cognitively simple approaches such as Weighted Sum and to a lesser degree SMART with this relatively limited data set. The more cognitively complex ...


A New Metric For Evaluating Machinability Of A Design, Jocelyn Chay, John K. Jackman, Matthew C. Frank, Frank E. Peters 2019 Iowa State University

A New Metric For Evaluating Machinability Of A Design, Jocelyn Chay, John K. Jackman, Matthew C. Frank, Frank E. Peters

Matthew C. Frank

With the increasing complexity of part model designs and the pressure to reduce time to market, evaluating the manufacturability of conceptual designs can help design engineers avoid part features that create downstream manufacturing problems. For machining processes, reachability of a part surface with a cutting tool plays a major role in determining the machinability of a design. This paper describes a new method to quantify reachability at different locations on the surface of a part model. A mesh representation (STL file) is generated for a part model and a slicing algorithm is used to estimate the reachability for each model ...


The Use Of Sacrificial Support Structures In A Rapid Machining Process, Wutthigrai Boonsuk, Matthew C. Frank 2019 Iowa State University

The Use Of Sacrificial Support Structures In A Rapid Machining Process, Wutthigrai Boonsuk, Matthew C. Frank

Matthew C. Frank

Rapid prototyping techniques for CNC machining have been developed in an effort to produce functional prototypes in appropriate materials. One of the major challenges is to develop an automatic fixturing system for the part during the milling process. The current proposed method, sacrificial support fixturing, is similar to the support structures used in existing rapid processes, such as Stereolithography. During the machining process, the sacrificial supports emerge incrementally and, at the end of the process, are the only entities connecting the part to the stock material. In this paper, we propose methodologies for the design of sacrificial support structures for ...


Visibility From A Slice File For Rapid Cnc Machining, Matthew C. Frank, Richard A. Wysk, Sanjay B. Joshi 2019 Iowa State University

Visibility From A Slice File For Rapid Cnc Machining, Matthew C. Frank, Richard A. Wysk, Sanjay B. Joshi

Matthew C. Frank

A methodology for using CNC machining as a rapid prototyping process is being developed. The method involves cutting complex parts using layer-based machining operations from a plurality of orientations about one axis of rotation. A critical step is to determine the number of and location of those orientations. This paper presents an approach to mapping the visibility of a model about an axis of rotation using a set of model slices taken orthogonal to the axis of rotation.


Probabilistic Methods For Long-Term Demand Forecasting For Aviation Production Planning, Minxiang Zhang, Cameron A. MacKenzie, Caroline Krejci, John K. Jackman, Guiping Hu, Charles Y. Hu, Gabriel A. Burnett, Adam A. Graunke 2019 Iowa State University

Probabilistic Methods For Long-Term Demand Forecasting For Aviation Production Planning, Minxiang Zhang, Cameron A. Mackenzie, Caroline Krejci, John K. Jackman, Guiping Hu, Charles Y. Hu, Gabriel A. Burnett, Adam A. Graunke

Guiping Hu

The aviation industry represents a complex system with low-volume high-value manufacturing, long lead times, large capital investments, and highly variable demand. Making important decisions with intensive capital investments requires accurate forecasting of future demand. However, this can be challenging because of significant variability in future scenarios. The use of probabilistic methods such as Brownian motion in forecasting has been well studied especially in the financial industry. Applying these probabilistic methods to forecast demand in the aerospace industry can be problematic because of the independence assumptions and no consideration of production system in these models. We used two forecasting models based ...


Capacity Planning And Production Scheduling For Aircraft Painting Operations, Xiangzhen Li, Caroline Krejci, Cameron A. MacKenzie, John K. Jackman, Guiping Hu, Charles Y. Hu, Adam A. Graunke, Gabriel A. Bumett 2019 Iowa State University

Capacity Planning And Production Scheduling For Aircraft Painting Operations, Xiangzhen Li, Caroline Krejci, Cameron A. Mackenzie, John K. Jackman, Guiping Hu, Charles Y. Hu, Adam A. Graunke, Gabriel A. Bumett

Guiping Hu

Long-term capacity planning and production scheduling present significant challenges for the aviation industry. Our research has integrated three different modeling methodologies to effectively forecast future demand for aircraft painting and then assess and manage the capacity that is needed to meet these requirements. First, an innovative forecasting approach was developed in which stochastic processes were used to model aircraft demand over a selected time interval. These demand forecasts were used as inputs to an integer programming model, which was used to find optimal monthly aircraft painting schedules. This approach supports for resource allocation that is based on optimal scheduling, rather ...


Applying Alternative Decision-Making Approaches To A Complex Supplier Selection Problem, Paul J. Componation, Michael C. Dorneich, Guiping Hu, Gillian M. Nicholls 2019 Iowa State University

Applying Alternative Decision-Making Approaches To A Complex Supplier Selection Problem, Paul J. Componation, Michael C. Dorneich, Guiping Hu, Gillian M. Nicholls

Guiping Hu

Prior work has been completed on understanding how an organization’s decision-making approach can influence the selection of alternative vendors when setting up a supply chain system. Teams using different decision-making approaches on identical performance data did end with different vendor recommendations. One possible explanation of this result was that the data set on vendor performance was limited to five vendors and four variables; however the decision-making approaches had significantly different cognitive requirements. The team members preferred cognitively simple approaches such as Weighted Sum and to a lesser degree SMART with this relatively limited data set. The more cognitively complex ...


Data Mining For Production Scheduling, Sigurdur Olafsson 2019 Iowa State University

Data Mining For Production Scheduling, Sigurdur Olafsson

Sigurdur Olafsson

Data mining is a fast growing field and many industrial engineering applications generate large amounts of data to which data mining techniques can be applied. In this paper we develop a data mining framework for production scheduling. This involves preprocessing of historic schedules into an appropriate data file, discovery of key scheduling concepts, and representation of the data mining results in a way that enables its use for job scheduling.


Developing And Testing Of An Upper Limb Exoskeleton For Stroke Patients, Drew Dudley, David Salazar 2019 University of Nebraska at Omaha

Developing And Testing Of An Upper Limb Exoskeleton For Stroke Patients, Drew Dudley, David Salazar

Student Research and Creative Activity Fair

Objective: The main objective of this study was to determine functional and neuromuscular outcomes of stroke patients using their non-preferred hand with and without a 3D printed passive exoskeleton compared to controls using their non-preferred hand with and without the passive exoskeleton. Methods: Adults at least six months post stroke (Stroke, n = 5) and age- and sex- matched healthy controls (Control, n = 5) performed nine trials of a gross motor task while having their brain activity measured. The Fugl-Meyer and “Box and Block” test was used to measure the gross dexterity of the subjects with and without the exoskeleton. Strength ...


Decreasing Technology Design Costs By Using Youtube Video To Evaluate User Acceptance, Tom Chappelear 2019 University of Nebraska at Omaha

Decreasing Technology Design Costs By Using Youtube Video To Evaluate User Acceptance, Tom Chappelear

Student Research and Creative Activity Fair

User acceptance is a measure that contributes to technology feasibility which is a decision point that entrepreneurs use to help make better investment decisions (Hoffer, 2011). User acceptance testing is part of a design strategy where the system designer attempts to minimize risks and provide design information that an entrepreneur can use to make better investment decisions (Hoffer, 2011). A user acceptance testing instruments can range from a low-cost coffeeshop review to expensive lab-based user testing (Shneiderman, 2017). This study builds upon the User Acceptance of Information Technology (UTAUT) model to measure user acceptance for the system being evaluated (Venkatesh ...


Efficacy Of Assistive Devices Produced With Additive Manufacturing, James Pierce 2019 University of Nebraska at Omaha

Efficacy Of Assistive Devices Produced With Additive Manufacturing, James Pierce

Student Research and Creative Activity Fair

Despite the frequency of musculoskeletal injuries such as sprains, broken bones and torn ligaments1, treatment options are often costly, time-consuming and ill-fitted.2,3 Additive manufacturing (“3D-printing) allows for the production of highly-customized and inexpensive assistive devices4, which suggests potential efficacy in the prescription of splints and casts for musculoskeletal injury.3 In the present study, a parametric, customizable splint/cast was created using a computer-aided design (CAD) package (Fusion 360, Autodesk, San Rafael, CA, USA) and produced with low-cost, desktop 3D printing (Ultimaker 2+ Extended, Ultimaker, Geldermalsen, Netherlands). Fitting of the devices was performed on five healthy ...


Visual Contributions To Balance Control During Gait, Kyle Brozek 2019 University of Nebraska at Omaha

Visual Contributions To Balance Control During Gait, Kyle Brozek

Student Research and Creative Activity Fair

We propose to isolate the contributions of continuous OF to the orthogonal relationship between balance and gait control during treadmill walking using a series of conditions. Manipulating the direction of OF using a CAREN (Motek Medical, Amsterdam, Netherlands) virtual reality treadmill environment will isolate these visual contributions in human subjects as they walk. We plan to tease out the effect of OF direction on the relationship between gait and balance control by having healthy young adults perform a series of treadmill walking trials while immersed in a VR environment. This will be done by manipulating the direction of walking and ...


Intensity And Pattern Of Daily Physical Activity Of Claudicating Patients, Cody Anderson 2019 University of Nebraska at Omaha

Intensity And Pattern Of Daily Physical Activity Of Claudicating Patients, Cody Anderson

Student Research and Creative Activity Fair

file:///C:/Users/codya/Desktop/Cody%20et%20al_2019_Human%20Movement%20Variability%20Conference.pdf


Gait Alterations After Anterior Cruciate Ligament Injury And Implications For Return-To-Play Testing, Lindsey Remski 2019 University of Nebraska at Omaha

Gait Alterations After Anterior Cruciate Ligament Injury And Implications For Return-To-Play Testing, Lindsey Remski

Student Research and Creative Activity Fair

Introduction: Reoccurring injury to the anterior cruciate ligament (ACL) is a major problem for individuals who undergo ACL reconstructive surgery despite them meeting current requirements for return-to-play. Previous studies have found alterations in gait kinetics and kinematics of ACL deficient and ACL reconstruction patients. It is unknown if gait parameters, such as peak joint angles and moments, provide different information about patient function from what is provided by return-to-play outcomes. Purpose: To assess the relationships between peak joint angles, peak joint moments, and return-to-play outcomes for individuals with ACL injury. Methods: 6 subjects (3 ACL reconstruction, 3 ACL deficient) performed ...


Determining The Relationship Between Walking Activity And Inter-Day Patterns In Stroke Survivors, Sydney Andreasen 2019 University of Nebraska at Omaha

Determining The Relationship Between Walking Activity And Inter-Day Patterns In Stroke Survivors, Sydney Andreasen

Student Research and Creative Activity Fair

Populations that have suffered from stroke are generally less active than people of otherwise similar demographics and are more susceptible to further health problems, such as another stroke. This study seeks to assess the validity of a treatment that encourages stroke survivors to walk more steps each day, in order to improve their active abilities and become less idle by establishing motivation for activity and therefore, also establishing patterns in the distribution of that activity throughout a stroke survivor’s day. 172 subjects (6 months post-stroke) have participated in a step activity monitoring program to record steps taken using wearable ...


Effects Of A Passive Dynamic Lower-Leg Exoskeleton During Walking, Blake Beier 2019 University of Nebraska at Omaha

Effects Of A Passive Dynamic Lower-Leg Exoskeleton During Walking, Blake Beier

Student Research and Creative Activity Fair

The ankle joint is one of the most important joints during walking. If the muscles surrounding the ankle are weak, there are reductions in the ability to generate appropriate torques and powers at the ankle. This leads to slower self-selected walking speeds, which correlate with poor physical functioning, more disabilities, increased hospitalization visits and costs, and even mortality. Because of this, many orthotic and exoskeletal devices have been created to restore proper ankle function by promoting ankle plantar flexion. Utilizing 3D printing and an extension spring, we created an easily accessible, reproducible, and modifiable exoskeleton that has the potential to ...


A Correlation Network Model For Managing Safety And Performance Issues In Bridges And Civil Infrastructures, Prasad Chetti 2019 University of Nebraska at Omaha

A Correlation Network Model For Managing Safety And Performance Issues In Bridges And Civil Infrastructures, Prasad Chetti

Student Research and Creative Activity Fair

Many recent studies have shown that a large percentage of bridges in many parts of the world have low safety rating. National Bridge Inventory (NBI) database contains the information of more than 600,000 bridges, where each bridge has 116 parameters. Current safety inspections require bridge inspectors to manually inspect each bridge every few years. Manpower and budget constraints limit such approach from inspecting the bridges more frequently. Clearly, more efficient approaches need to be developed to improve the process of bridge inspection and increase the overall safety of bridges and civil infrastructures. In this study, we propose a Correlation ...


A Voice Activated Prosthetic Mode Of Control, Will Picken 2019 University of Nebraska at Omaha

A Voice Activated Prosthetic Mode Of Control, Will Picken

Student Research and Creative Activity Fair

There are many options for a prosthetic mode of control. The most commonly created modes of control involve surface EMG (sEMG) and require that the user have well defined muscle activation in order to trigger the movement of the prosthetic. Unfortunately, many prosthetic users do not have the required muscle tone or strength to trigger these sensors, so the need for a control mechanism that doesn’t rely on sEMG is clear. This study focuses on the development of a low-cost, voice activated prosthetic mode of control compatible with the prosthetics developed by Dr. Zuniga and his research team.

The ...


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