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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 ...


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.


Enhancing Suborbital Science Through Better Understanding Of Wind Effects, Pedro Llanos, Diane Howard 2019 Embry-Riddle Aeronautical University - Daytona Beach

Enhancing Suborbital Science Through Better Understanding Of Wind Effects, Pedro Llanos, Diane Howard

Space Traffic Management Conference

This paper highlights the importance of understanding some key factors, such as winds effects, trajectory and vehicle parameters variations in order to streamline the space vehicle operations and enhance science in the upper mesosphere at about 85 km. Understanding these effects is crucial to refine current space operations and establish more robust procedures. These procedures will involve training new space operators to conduct and coordinate space operations in class E above FL600 airspace within the Air Traffic Organization (ATO).

Space vehicles such as Space Ship Two can spend up to 6 minutes in class E airspace above FL600 after launch ...


A Statistical Approach For Commercial Space Vehicle Integration Into The National Airspace System, Christopher Hays, Daniel Chu, Pedro Llanos 2019 Embry-Riddle Aeronautical University

A Statistical Approach For Commercial Space Vehicle Integration Into The National Airspace System, Christopher Hays, Daniel Chu, Pedro Llanos

Space Traffic Management Conference

This paper explores commercial space vehicle (CSV) suborbital flight trajectories in the temporal and spatial domains for CSV integration into the National Airspace System. The research data was collected via the Suborbital Space Flight Simulator (SSFS) housed in the College of Aviation at Embry-Riddle Aeronautical University - Daytona Beach campus, and analyzed using an original MATLAB data analytics tool. This study primarily focuses on statistical trends observed in previously simulated flights supported by three Project PoSSUM (Polar Suborbital Science in the Upper Mesosphere) campaigns comprised of 34 flights and 19 control flights, and to identify relevant milestones in the CSV flight ...


Decision Science For Community Development And Social Change, Michael P. Johnson Jr. 2019 University of Massachusetts - Boston

Decision Science For Community Development And Social Change, Michael P. Johnson Jr.

Michael P. Johnson

Operations research, also known as management science or decision science, is a mathematics-based discipline that draws from engineering, information systems, management, public policy and planning. OR enables individuals and organizations to make better decisions regarding manufacturing and logistics, service provision and strategy design. My particular interest in OR focuses on the needs of mission-driven and resource-constrained organizations that serve urban communities. In my talk I will describe how OR can use qualitative and quantitative analysis through meaningful engagement of communities to enable creative identification, formulation and solution of complex problems for local impact and social justice. Specific applications I'm ...


Self-Leadership To Servant Leadership: A Metatheoretical Antecedent To Positive Social, Allen Lloyd Carn 2019 Walden University

Self-Leadership To Servant Leadership: A Metatheoretical Antecedent To Positive Social, Allen Lloyd Carn

Walden Dissertations and Doctoral Studies

A majority of current leadership programs are failing to deliver a comprehensive approach to leadership development by not providing middle and frontline managers the skills to enhance their potential to develop others. In failing to generate a comprehensive system, animosity towards all types of leadership has been festering for over 40 years as first identified by Greenleaf in 1977. The purpose of the study was to establish a link between the theoretical paradigms of servant leadership and self-leadership using the lens of emotional intelligence to generate an integral leadership development framework. The conceptual framework used Goleman et al.'s version ...


A Game-Theoretic Approach To Share The Costs Of Cooperating Healthcare Networks, Jay M. Lightfoot 2019 University of Northern Colorado

A Game-Theoretic Approach To Share The Costs Of Cooperating Healthcare Networks, Jay M. Lightfoot

Journal of International Technology and Information Management

The growing demand for healthcare services combined with the disarray in the health insurance market in the United States has created a situation where rival health networks are aggressively competing by building duplicate health facilities and providing redundant services in localized geographic regions. Unfortunately, this strategy can reduce the quality of patient care and decrease profits (Kaissi & Charland, 2013). A solution to this problem is for health networks to cooperate and share healthcare equipment, facilities, and personnel. Toward that end, this paper presents a game-theoretic method that can share these costs in a fair, efficient, and repeatable manner.


A Systematic Review Of Process Modelling Methods And Its Application For Personalised Adaptive Learning Systems, Kingsley Okoye 2019 University of East London

A Systematic Review Of Process Modelling Methods And Its Application For Personalised Adaptive Learning Systems, Kingsley Okoye

Journal of International Technology and Information Management

This systematic review work investigates current literature and methods that are related to the application of process mining and modelling in real-time particularly as it concerns personalisation of learning systems, or yet still, e-content development. The work compares available studies based on the domain area of study, the scope of the study, methods used, and the scientific contribution of the papers and results. Consequently, the findings of the identified papers were systematically evaluated in order to point out potential confounding variables or flaws that might have been overlooked or missing in the current literature. In turn, a critical structured analysis ...


Crude Oil Prices Forecasting: Time Series Vs. Svr Models, Xin James He 2018 Fairfield University

Crude Oil Prices Forecasting: Time Series Vs. Svr Models, Xin James He

Journal of International Technology and Information Management

This research explores the weekly crude oil price data from U.S. Energy Information Administration over the time period 2009 - 2017 to test the forecasting accuracy by comparing time series models such as simple exponential smoothing (SES), moving average (MA), and autoregressive integrated moving average (ARIMA) against machine learning support vector regression (SVR) models. The main purpose of this research is to determine which model provides the best forecasting results for crude oil prices in light of the importance of crude oil price forecasting and its implications to the economy. While SVR is often considered the best forecasting model in ...


Table Of Contents Jitim Vol 27 Issue 3, 2018, 2018 California State University, San Bernardino

Table Of Contents Jitim Vol 27 Issue 3, 2018

Journal of International Technology and Information Management

Table of Contents


Cost Benefit Analysis Of Led Vs Florescent Lighting, Kurtis Clark, Phillip Humphrey 2018 Southwestern Oklahoma State University

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 ...


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

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 ...


A Mathematical Framework On Machine Learning: Theory And Application, Bin Shi 2018 Florida International University

A Mathematical Framework On Machine Learning: Theory And Application, Bin Shi

FIU Electronic Theses and Dissertations

The dissertation addresses the research topics of machine learning outlined below. We developed the theory about traditional first-order algorithms from convex opti- mization and provide new insights in nonconvex objective functions from machine learning. Based on the theory analysis, we designed and developed new algorithms to overcome the difficulty of nonconvex objective and to accelerate the speed to obtain the desired result. In this thesis, we answer the two questions: (1) How to design a step size for gradient descent with random initialization? (2) Can we accelerate the current convex optimization algorithms and improve them into nonconvex objective? For application ...


Maximizing Financial Benefit Of Lean Six Sigma Projects Through Optimized Selection Criteria, Colin Wasiloff 2018 Southern Methodist University

Maximizing Financial Benefit Of Lean Six Sigma Projects Through Optimized Selection Criteria, Colin Wasiloff

Engineering Management, Information, and Systems Research Theses and Dissertations

As evolving threats across the globe keep pace with increasing budget constraints, the US Army’s major subordinate commands and their sub-organizations are constantly challenged to do more with less. Resources such as human capital, information technology, facilities, and budgeted funding are stretched as thin as ever, while requirements to serve the Warfighter remain paramount. Each dollar of financial benefit gained through cost reduction efforts at the US Army can affect the Warfighter directly. Budgeted money saved or avoided is reprogrammed both locally and atop the hierarchy at the Department of Treasury to serve the Warfighter better.

Ordinal Logistic Regression ...


Developing An Optimized Ui For Traffic Incident Managers, Andrina Helgerson, Jamiahus Walton, Celia Loya, Christopher Kawell, Katherine Atwell, Quinn Monaghan, Lakshay Ahuja, Hesham Hassan, Stephen B. Gilbert, Anuj Sharma 2018 Iowa State University

Developing An Optimized Ui For Traffic Incident Managers, Andrina Helgerson, Jamiahus Walton, Celia Loya, Christopher Kawell, Katherine Atwell, Quinn Monaghan, Lakshay Ahuja, Hesham Hassan, Stephen B. Gilbert, Anuj Sharma

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Traffic Incident Managers (TIMs) coordinate first responders and help resolve traffic-related incidents. Currently, some use over fifteen different software applications with unique functionalities across three monitors to manage incidents, leading to redundant data entry, unnecessary task switching, and delayed responses. 40 hours of TIMs’ screens were recorded during their normal work hours at the Iowa Department of Transportation (DoT). The resulting task analysis from these videos greatly influenced the design of a simplified, web-based, user interface (UI) prototype. The new UI offers a 42.9% reduction in the steps required to manage an incident by combining the functionality of the ...


Vastus And Patellar Protection With Range Of Motion Pad – Advanced Personal Protective Equipment For The Lower Body, Richard T. Stone, Brandon Moeller, Thomas M. Schnieders, Ahmad Mumani 2018 Iowa State University

Vastus And Patellar Protection With Range Of Motion Pad – Advanced Personal Protective Equipment For The Lower Body, Richard T. Stone, Brandon Moeller, Thomas M. Schnieders, Ahmad Mumani

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

The standard knee pad is considered the most ineffective personal protective equipment in the American football player’s uniform. This study quantitatively and qualitatively assesses personal protective equipment for the lower body for U.S. football players against the VAPPR Pad (Vastus And Patellar Protection with Range of motion), the next iteration of lower body protection. The study consisted of player surveys, material drop testing, and Performance Drill testing including broad-jump, L-drill, pro-agility, and gait analysis with 138 participants in the initial survey and 25 men in the physical testing. Results of the Performance Drill Testing proved that unpadded players ...


Feedback Design Considerations For Intelligent Team Tutoring Systems, Jamiahus Walton, Alec Ostrander, Kaitlyn M. Ouverson, Stephen B. Gilbert, Michael C. Dorneich, Eliot H. Winer, Anne Sinatra 2018 Iowa State University

Feedback Design Considerations For Intelligent Team Tutoring Systems, Jamiahus Walton, Alec Ostrander, Kaitlyn M. Ouverson, Stephen B. Gilbert, Michael C. Dorneich, Eliot H. Winer, Anne Sinatra

Industrial and Manufacturing Systems Engineering Conference Proceedings and Posters

Challenges arise when developing a computer-based Intelligent Team Tutoring System (ITTS) that attempts to deliver feedback to teams as effectively as a human tutor. The purpose of this current work is to outline elements of feedback that should be considered when designing feedback for an ITTS. The authors present the results of a study that consisted of 32 participants grouped into 16 teams of two. Each team conducted a surveillance task where they received individual or team feedback. Feedback content was written using either the bald (direct feedback; no need for interpretation) or off-record (general feedback; interpretation needed) etiquette strategy ...


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