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Articles 1 - 30 of 31

Full-Text Articles in Systems Engineering

Toilet Alarms: A Novel Application Of Latrine Sensors And Machine Learning For Optimizing Sanitation Services In Informal Settlements, Phillip Nicholas Turman-Bryant, Taylor Sharpe, Corey L. Nagel, Lauren Stover, Evan A. Thomas Jan 2020

Toilet Alarms: A Novel Application Of Latrine Sensors And Machine Learning For Optimizing Sanitation Services In Informal Settlements, Phillip Nicholas Turman-Bryant, Taylor Sharpe, Corey L. Nagel, Lauren Stover, Evan A. Thomas

Systems Engineering Faculty Publications and Presentations

The cost-effectiveness and reliability of waste collection services in informal settlements can be difficult to optimize given the geospatial and temporal variability of latrine use. Daily servicing to avoid overflow events is inefficient, but dynamic scheduling of latrine servicing could reduce costs by providing just-in-time servicing for latrines. This study used cellular-connected motion sensors and machine learning to dynamically predict when daily latrine servicing could be skipped with a low risk of overflow. Sensors monitored daily latrine activity, and enumerators collected solid and liquid waste weight data. Given the complex relationship between latrine use and the need for servicing, an …


Managing Healthcare Data Assets As A Complex Adaptive System, Katie Clifton Mar 2019

Managing Healthcare Data Assets As A Complex Adaptive System, Katie Clifton

Systems Science Friday Noon Seminar Series

A major project is underway to develop a shared platform for data and analytics in a highly federated healthcare delivery organization. In the status quo data environment, analysts have integrated information from various domains — medical records, claims, membership — to produce a multitude of reports and analysis. Duplicative, mis-aligned, and siloed datasets were created as an unintended consequence.

One objective of the project is to produce outcomes (reports, analysis) that are more standardized and efficient than the status quo without sacrificing adaptability. Standards and practices are being intentionally developed as a mechanism for this emerging system to achieve more …


Iot And Digitization Will Reconnect System Engineering And Science, John Blyler Feb 2019

Iot And Digitization Will Reconnect System Engineering And Science, John Blyler

Systems Science Friday Noon Seminar Series

The fully connected world is quickly becoming a reality. Architects and developers of this new world must understand both the hardware and software basics of IoT and IIoT systems as well as the proven way to deal with the complexities of the integration of sensors, processors, wireless connectivity, edge to cloud networks, data partitioning and processing, AI, machine language, digital threads and twins, and much more. Such complexity can only be handled with a systems-of-systems (SoS) engineering approach.

But while systems engineering may hold many of the solutions to IoT challenges, systems engineering must evolve from its traditional role. Some …


Teen Driver System Modeling: A Tool For Policy Analysis, Celestin Missikpode, Corrine Peek-Asa, Daniel V. Mcgehee, James Torner, Wayne Wakeland, Robert Wallace Dec 2018

Teen Driver System Modeling: A Tool For Policy Analysis, Celestin Missikpode, Corrine Peek-Asa, Daniel V. Mcgehee, James Torner, Wayne Wakeland, Robert Wallace

Systems Science Faculty Publications and Presentations

Background: Motor vehicle crashes remain the leading cause of teen deaths in spite of preventive efforts. Prevention strategies could be advanced through new analytic approaches that allow us to better conceptualize the complex processes underlying teen crash risk. This may help policymakers design appropriate interventions and evaluate their impacts.

Methods: System Dynamics methodology was used as a new way of representing factors involved in the underlying process of teen crash risk. Systems dynamics modeling is relatively new to public health analytics and is a promising tool to examine relative influence of multiple interacting factors in predicting a health …


Reflections On Teaching System Dynamics Modeling To Secondary School Students For Over 20 Years, Diana Fisher Jan 2018

Reflections On Teaching System Dynamics Modeling To Secondary School Students For Over 20 Years, Diana Fisher

Systems Science Faculty Publications and Presentations

This paper contains the description of a successful system dynamics (SD) modeling approach used for almost a quarter-century in secondary schools, both in algebra classes and in a year-long SD modeling course. Secondary school students have demonstrated an ability to build original models from the news, write technical papers explaining their models, and present a newfound understanding of dynamic feedback behavior to an audience. The educational learning theory and instructional methods used for both the algebra and modeling courses are detailed, with examples. Successful student SD modeling experiences suggest the SD approach can expand the sophistication of topics that secondary …


On Valuing Biopharmaceutical Product Pipelines: An Effectuation Model And Evidence, Mark J. Ahn, Anne S. York, Wei Wu, Yulianto Suharto, Tugrul Unsal Daim Dec 2015

On Valuing Biopharmaceutical Product Pipelines: An Effectuation Model And Evidence, Mark J. Ahn, Anne S. York, Wei Wu, Yulianto Suharto, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

New creative approaches are needed to manage emerging biotechnology innovations, regulations, and payor environments to enhance product pipeline productivity, valuation, and risk management. Biopharmaceutical firms must make dynamic resource allocation decisions on their relative levels of internal R&D and external strategic alliances in furthering their pipelines. As the predominant method of using discounted cash flow (DCF) methodologies may lead to chronic underinvestment and performance, we evaluated the integration of traditional DCF with an effectuation model of analysis. Unlike traditional financial models that begin with the end goal of assumed known cash flows and recursively solve for portfolio optimization, the effectuation …


The Prediction Predicament, William "Ike" Eisenhauer Dec 2015

The Prediction Predicament, William "Ike" Eisenhauer

Engineering and Technology Management Faculty Publications and Presentations

The article focuses on the prediction of predicament in terms of forecasting at industrial engineering level. Topics discussed include business optimize resources via forecasting; audience who cannot comprehend the methodology used for forecasting in healthcare operations; and use of forecasting for performance measurement.


The Time Has Come For Nursing Engineering, William "Ike" Eisenhauer Aug 2015

The Time Has Come For Nursing Engineering, William "Ike" Eisenhauer

Engineering and Technology Management Faculty Publications and Presentations

The article discusses the need for healthcare and educational organizations to create nursing engineering program. Topics discussed include successes in healthcare systems as engineers and healthcare professionals, integration of industrial engineering or lean and Six Sigma courses into nursing programs of the University of Alabama and modern healthcare system and modern healthcare participants that can be addressed by the new profession.


Don't Go Chasing Big Waterfalls, William "Ike" Eisenhauer Jun 2015

Don't Go Chasing Big Waterfalls, William "Ike" Eisenhauer

Engineering and Technology Management Faculty Publications and Presentations

The article focuses on the importance of simpler health systems in the U.S. Topics discussed include success of simple systems as they are well-understood, improvement of simple systems by coupling them together, handling more patient cases by larger systems by the medical laboratory technicians giving complicated results and designing simple systems by health system engineers to deal with fewer problematic cases of patients with more efficacy.


Modeling The Impact Of Simulated Educational Interventions On The Use And Abuse Of Pharmaceutical Opioids In The United States: A Report On Initial Efforts, Wayne Wakeland, Alexandra E. Nielsen, Teresa D. Schmidt, Dennis Mccarty, Lynn Webster, John Fitzgerald, J. David Haddox Oct 2013

Modeling The Impact Of Simulated Educational Interventions On The Use And Abuse Of Pharmaceutical Opioids In The United States: A Report On Initial Efforts, Wayne Wakeland, Alexandra E. Nielsen, Teresa D. Schmidt, Dennis Mccarty, Lynn Webster, John Fitzgerald, J. David Haddox

Systems Science Faculty Publications and Presentations

Three educational interventions were simulated in a system dynamics model of the medical use, trafficking, and nonmedical use of pharmaceutical opioids. The study relied on secondary data obtained in the literature for the period of 1995 to 2008 as well as expert panel recommendations regarding model parameters and structure. The behavior of the resulting systems-level model was tested for fit against reference behavior data. After the base model was tested, logic to represent three educational interventions was added and the impact of each intervention on simulated overdose deaths was evaluated over a 7-year evaluation period, 2008 to 2015. Principal findings …


Cytoskeletal Strains In Modeled Optohydrodynamically Stressed Healthy And Diseased Biological Cells, Sean S. Kohles, Yu Liang, Asit K. Saha Dec 2012

Cytoskeletal Strains In Modeled Optohydrodynamically Stressed Healthy And Diseased Biological Cells, Sean S. Kohles, Yu Liang, Asit K. Saha

Mechanical and Materials Engineering Faculty Publications and Presentations

Controlled external chemomechanical stimuli have been shown to influence cellular and tissue regeneration/degeneration, especially with regards to distinct disease sequelae or health maintenance. Recently, a unique three-dimensional stress state was mathematically derived to describe the experimental stresses applied to isolated living cells suspended in an optohydrodynamic trap (optical tweezers combined with microfluidics). These formulae were previously developed in two and three dimensions from the fundamental equations describing creeping flows past a suspended sphere. The objective of the current study is to determine the full-field cellular strain response due to the applied three-dimensional stress environment through a multiphysics computational simulation. In …


Leveraging Carbon Financing To Enable Accountable Water Treatment Programs, Evan A. Thomas Oct 2012

Leveraging Carbon Financing To Enable Accountable Water Treatment Programs, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

This article outlines the technical premise and policy considerations surrounding the first program to generate carbon finance for drinking water treatment.


Measuring Sustainability, Evan A. Thomas Aug 2012

Measuring Sustainability, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

The World Health Organization estimates that 884 million people do not have access to safe sources of drinking water. Meanwhile, about half of the world's population continues to use unsustainable, biomassbased energy sources for indoor fuel, leading to extensive deforestation, harmful indoor air emissions, and in many cases upper respiratory disease and high commodity costs for impoverished families. Exacerbating these problems are the international effects of climate change, expected to significantly impact developing countries by changing water and energy quality and availability. International development organizations work tirelessly to address these challenges. However, many efforts struggle with achieving long-term sustainability; many …


Bring Your Own Water Treatment System: United States Patent, Evan A. Thomas, Maximilian Gold Aug 2011

Bring Your Own Water Treatment System: United States Patent, Evan A. Thomas, Maximilian Gold

Mechanical and Materials Engineering Faculty Publications and Presentations

A method and apparatus for filtering a fluid is presented. In one embodiment, the apparatus converts contaminated water into water having a lower turbidity and bacterial contamination level than the contaminated water. The apparatus includes a settling unit for at least partially settling a portion of the water; a filter unit having a filtration media; wherein the filtration media comprises sand, anthracite coal, burnt rice husks, diatomaceous earth, gravel, pumice gravel, or combinations thereof; a sanitation unit; wherein the sanitation unit is an ultraviolet disinfection unit; a backwash unit; wherein the settling unit is in fluid communications with the filter …


Social Innovation Concepts At Nasa: Integrating International Development Challenges And Hands-On Prototyping With Spacecraft Design Training, Leonard Yowell, Evan A. Thomas Jul 2011

Social Innovation Concepts At Nasa: Integrating International Development Challenges And Hands-On Prototyping With Spacecraft Design Training, Leonard Yowell, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

The NASA Johnson Space Center Social Innovation program has been designed to encourage innovation within the NASA community that benefits both NASA's core mission as well as human needs domestically and internationally. By encouraging internal and external collaboration and providing resources including the new Johnson Space Center "Sandbox" design shop, new innovations are anticipated. Technologies developed for the human exploration of space share similar requirements with appropriate technology for the developing world. The technology goals of keeping people alive in a difficult environment involve addressing requirements for low maintenance and robustness and often include using renewable energy sources. Technologies developed …


Sustainable Oxygen: A Low Power Approach For Providing Emergency Medical Oxygen For Spacecraft And Hospitals In Developing Countries, Anndee L. Huff, Evan Rhead, Zdenek Zumr, Evan A. Thomas Jul 2011

Sustainable Oxygen: A Low Power Approach For Providing Emergency Medical Oxygen For Spacecraft And Hospitals In Developing Countries, Anndee L. Huff, Evan Rhead, Zdenek Zumr, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

An oxygen concentrator targeting an 80% reduction in power demand over commercial systems is being developed using a pressure swing adsorption process. This system is targeted for a service interval five times longer than commercial systems, and is tolerant to high humidity environments- the leading cause of device failure in developing countries. This system could provide emergency medical oxygen in a spacecraft without increasing oxygen concentration in the vehicle. Flight surgeons seek this capability, but presently, there is no system that meets power, size, and delivery rate requirements. This type of system is also well suited for medical oxygen in …


Systems Ideas For The Scientific And Societal Imperatives Of The Coastal Ocean: Case Of The Bp Oil Gusher In The Gulf Of Mexico, Spring & Summer 2010, Christopher Mooers May 2011

Systems Ideas For The Scientific And Societal Imperatives Of The Coastal Ocean: Case Of The Bp Oil Gusher In The Gulf Of Mexico, Spring & Summer 2010, Christopher Mooers

Systems Science Friday Noon Seminar Series

In recent decades, great progress has been made in advancing the scientific understanding of the coastal ocean (i.e., the 200 nautical mile Exclusive Economic Zone (EEZ)) across a broad set of disciplines. Simultaneously, the societal use of the coastal ocean has skyrocketed through, for example, increased shipping & boating, sports & commercial fishing, and exploitation of non-living resources, such as, oil & gas extraction and sand & gravel mining. International law and national policy assign coastal nations the responsibility for stewardship (i.e., wise management) of their respective EEZs. The scope of the stewardship and applications can be summarized as (1) …


Proving Sustainability: The International Development Monitoring Initiative, Evan A. Thomas, Zdenek Zumr Jan 2011

Proving Sustainability: The International Development Monitoring Initiative, Evan A. Thomas, Zdenek Zumr

Mechanical and Materials Engineering Faculty Publications and Presentations

Nearly a billion people in the world lack access to safe drinking water, two billion have inadequate sanitation facilities, three billion use biomass for their daily energy needs and nearly half the world's population live in rural isolation, lacking access to the most basic human services. Combined, these limitations are a leading cause of the perpetuating cycle of poverty and political insecurity. Meanwhile, the majority of international development agencies are responsible for self-reporting project outcomes. At best, expert spot-checks are conducted in the field occasionally. These results tend to show individual project success, while meta- surveys indicate on-going challenges in …


Presentation: Proving Sustainability: The International Development Monitoring Initiative, Evan A. Thomas Jan 2011

Presentation: Proving Sustainability: The International Development Monitoring Initiative, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

Presentation detailing the activities and products of the Sustainable Water, Energy and Environmental Technologies Laboratory at Portland State University (SWEETLab). The lab also works to develop standards to help evaluate and compare projects and outcomes around the world. Water treatment and sanitation practices, as well as newly designed cookstoves, are highlighted.


How A Systems Engineer Starts..., Herman Migliore Oct 2010

How A Systems Engineer Starts..., Herman Migliore

Systems Science Friday Noon Seminar Series

Dr. Migliore will review systems engineering as a process for developing products, processes, and services and suggest views that encourage systems thinking. As an example, he will focus on the beginning of the development process, the fuzzy front end, and discuss a method, ConOps, for getting started using examples from PSU's masters program.


Developing Sustainable Life Support System Concepts, Evan A. Thomas Jul 2010

Developing Sustainable Life Support System Concepts, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

Sustainable spacecraft life support concepts may allow the development of more reliable technologies for long-duration space missions. Currently, life support technologies at different levels of development are not well evaluated against each other, and evaluation methods do not account for long-term reliability and sustainability of the hardware. This paper presents point-of-departure Sustainable System Mass (SSM) evaluation criteria for life support systems that may allow more robust technology development, testing, and comparison. An example sustainable water recovery system concept is presented.


Second-Generation International Space Station Total Organic Carbon Analyzer Verification Testing And On-Orbit Performance Results, Nicole L. Bentley, Evan A. Thomas, Michael Van Wie, Chad Morrison Jul 2010

Second-Generation International Space Station Total Organic Carbon Analyzer Verification Testing And On-Orbit Performance Results, Nicole L. Bentley, Evan A. Thomas, Michael Van Wie, Chad Morrison

Mechanical and Materials Engineering Faculty Publications and Presentations

The International Space Station (ISS) total organic carbon analyzer (TOCA) is designed to autonomously assess recovered water quality by providing an indication of total organic carbon (TOC). The current TOCA has been on the ISS since November 2008. Functional checkout and operations revealed complex operating considerations. Specifically, failure of the hydrogen (H2) catalyst resulted in development of an innovative oxidation analysis method. This method reduces activation time and limits the H2 produced during analysis, while retaining the ability to indicate TOC concentrations within 25% accuracy. Subsequent testing and comparison to archived samples returned from the station and tested on the …


Development Of A Contingency Capillary Wastewater Management Device, Evan A. Thomas Jan 2010

Development Of A Contingency Capillary Wastewater Management Device, Evan A. Thomas

Mechanical and Materials Engineering Faculty Publications and Presentations

The personal body-attached liquid liquidator (PBALL) is conceived as a passive, capillary-driven, contingency wastewater disposal device. In this contingency scenario, the airflow system on the NASA crew exploration vehicle is assumed to have failed, leaving only passive hardware and vacuum vent to dispose of wastewater. To meet these needs, the PBALL was conceived to rely on capillary action and urine wetting conditions from 0° < θadv ∼ 90°, be adaptable for both male and female use, collect and retain up to 1 L of urine, minimize splash-back, and allow continuous draining of the wastewater to vacuum while minimizing cabin air loss. A subscale PBALL test article, which was tested on NASA's reduced-gravity aircraft in April 2010, successfully demonstrated key components of this design.


A Model For Sustainable Humanitarian Engineering Projects, Evan A. Thomas, Bernard Amadei, Robyn Sandekian Nov 2009

A Model For Sustainable Humanitarian Engineering Projects, Evan A. Thomas, Bernard Amadei, Robyn Sandekian

Mechanical and Materials Engineering Faculty Publications and Presentations

The engineering profession should embrace a new mission statement?to contribute to the building of a more sustainable, stable, and equitable world. Recently, engineering students and professionals in the United States have shown strong interest in directly addressing the needs of developing communities worldwide. That interest has taken the form of short-and medium-term international trips through Engineers Without Borders?USA and similar organizations. There are also several instances where this kind of outreach work has been integrated into engineering education at various US institutions such as the University of Colorado at Boulder. This paper addresses the challenges and opportunities associated with balancing …


Optical Acquisition And Polar Decomposition Of The Full-Field Deformation Gradient Tensor Within A Fracture Callus, Wangdo Kim, Sean S. Kohles Sep 2009

Optical Acquisition And Polar Decomposition Of The Full-Field Deformation Gradient Tensor Within A Fracture Callus, Wangdo Kim, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Tracking tissue deformation is often hampered by material inhomogeneity, so local measurements tend to be insufficient thus lending to the necessity of full-field optical measurements. This study presents a novel approach to factoring heterogeneous deformation of soft and hard tissues in a fracture callus by introducing an anisotropic metric derived from the deformation gradient tensor (F). The deformation gradient tensor contains all the information available in a Green-Lagrange strain tensor, plus the rigid-body rotational components. A recent study [Bottlang et al., J. Biomech. 41(3), 2008] produced full-field strains within ovine fracture calluses acquired through the application of electronic speckle pattern …


Developing Sustainable Spacecraft Water Management Systems, Evan A. Thomas, David M. Klaus Jan 2009

Developing Sustainable Spacecraft Water Management Systems, Evan A. Thomas, David M. Klaus

Mechanical and Materials Engineering Faculty Publications and Presentations

It is well recognized that water handling systems used in a spacecraft are prone to failure caused by biofouling and mineral scaling, which can clog mechanical systems and degrade the performance of capillary-based technologies. Long duration spaceflight applications, such as extended stays at a Lunar Outpost or during a Mars transit mission, will increasingly benefit from hardware that is generally more robust and operationally sustainable overtime. This paper presents potential design and testing considerations for improving the reliability of water handling technologies for exploration spacecraft. Our application of interest is to devise a spacecraft wastewater management system wherein fouling can …


Using Agent Based Simulation And Game Theory Analysis To Study Information Sharing In Organizations – The Infoscape, Richard Donald Jolly, Wayne W. Wakeland Jan 2008

Using Agent Based Simulation And Game Theory Analysis To Study Information Sharing In Organizations – The Infoscape, Richard Donald Jolly, Wayne W. Wakeland

Systems Science Faculty Publications and Presentations

Information sharing in organizations, especially the impact of sharing freely versus not sharing, was studied using game theory and agent based simulation. A game theoretic analysis was performed, and Netlogo simulations were carried out wherein some agents hoarded information while others shared information. As expected, sharing was found to greatly increase the overall amount of information within the organization. Unexpectedly, agents who share acquire more information than hoarders. This is due to the synergy that develops between groups of agents who are sharing with each other. The density of the agents is important-as the density increases, the probability increases that …


Emergence Of Networks In Distance-Constrained Trade, Kumar Venkat, Wayne W. Wakeland Jan 2008

Emergence Of Networks In Distance-Constrained Trade, Kumar Venkat, Wayne W. Wakeland

Systems Science Faculty Publications and Presentations

Long-distance trade has been rapidly increasing in recent years. As traders from around the world exchange goods, they form networks with traders as nodes and transactions as links. We use an agent-based model of a simple artificial economy to examine the emergence of trade networks when the distance between traders matters. Distance can become an issue if fuel for transportation becomes expensive or if greenhouse gas emissions from transportation become a major concern. We model the distance constraint as a transaction cost proportional to the amount of goods traded and the distance that those goods must be transported. We find …


Development And Implementation Of The Bring Your Own Water Treatment System In Dense, Rural, And Mountainous Rwandan Communities, Maximilian Gold, Evan A. Thomas, Richard L. Byyny, Jean Pierre Habanabakize Jan 2007

Development And Implementation Of The Bring Your Own Water Treatment System In Dense, Rural, And Mountainous Rwandan Communities, Maximilian Gold, Evan A. Thomas, Richard L. Byyny, Jean Pierre Habanabakize

Mechanical and Materials Engineering Faculty Publications and Presentations

Over a billion people in the world lack access to safe drinking water1. While numerous technological, medical, and educational solutions have been implemented for the benefit of disadvantaged communities, there is no 'magic bullet'. Instead, development agencies must partner directly with these communities to address their public health needs through appropriate technology solutions, backed up by education and assessment. The "Bring Your Own Water (BYOW) Treatment System" developed by the Engineers Without Borders-USA chapters at the University of Colorado at Boulder Chapter (EWB-CU) and the Johnson Space Center (EWB-JSC) is uniquely designed to address the water treatment requirements of two …


Engineering Education Through Service-Learning In Developing Communities: Two Case Studies, Evan A. Thomas, Andrew Azman Jan 2006

Engineering Education Through Service-Learning In Developing Communities: Two Case Studies, Evan A. Thomas, Andrew Azman

Mechanical and Materials Engineering Faculty Publications and Presentations

This paper provides case studies of two service learning projects that University of Colorado at Boulder (CU-Boulder) students are integrating into their academic experience. The projects focus on developing communities and are managed under the auspices of Engineers Without Borders-USA (EWB-USA), a group founded by Dr. Bernard Amadei, Professor of Civil Engineering at CU-Boulder. These projects expand students? understanding of the social value of their chosen profession, and expose them to a type of engineering significantly different than what is presented in most of their classes. Specifically, focusing on developing communities provides students with the opportunity to design solutions to …