Systems Engineering Commons^™

Long-Term Functionality Of Rural Water Services In Developing Countries: A System Dynamics Approach To Understanding The Dynamic Interaction Of Causal Factors, Jeffrey P. Walters, Amy N. Javernick-Will

Faculty Publications - Biomedical, Mechanical, and Civil Engineering

Research has shown that sustainability of rural water infrastructure in developing countries is largely affected by the dynamic and systemic interactions of technical, social, financial, institutional, and environmental factors that can lead to premature water system failure. This research employs systems dynamic modeling, which uses feedback mechanisms to understand how these factors interact dynamically to influence long-term rural water system functionality. To do this, the research first identified and aggregated key factors from literature, then asked water sector experts to indicate the polarity and strength between factors through Delphi and cross impact survey questionnaires, and finally used system dynamics modeling …

Warrior Information Network- Tactical Human View Models & Analysis, Holly A. H. Handley, Cansu Kandemir, Elnaz Dario

Engineering Management & Systems Engineering Faculty Publications

The Human View collects and categorizes data to provide information and analyses on the human component of a system. This organization of human system data helps to understand what the impact of the technology on human performance may be. The first phase of this project completed exploratory work on different Human View techniques in the context of the Warrior Information Network - Tactical (WIN-T) system. This included creating a high-level diagram to provide a conceptual realization of a General Purpose User (GPU) interacting with the WIN-T system, creating engineering diagrams using the System Modeling Language (SysML) to render the Human …

Alternate Models For Natural Gas Transportation System Performance Optimization, Gnana Shekaran Arumugam

Theses and Dissertations--Manufacturing Systems Engineering

The Natural Gas market in the U.S is growing rapidly with evidence that the nation has enough shale reserves to power the country for the next century. To ensure continued economic benefits through the use of this environmentally desired energy source, it becomes important to optimize the transportation network system design. Transportation through pipelines is one of the most common methods used to distribute Natural Gas from source to destination. This transportation system, consisting of pipelines, compressors and other supporting equipment, must be optimized, considering all relevant parameters to minimize cost and increase profit. The research presented here improves on …

Analyzing Stakeholders Using Fuzzy Cognitive Mapping, Patrick T. Hester

Engineering Management & Systems Engineering Faculty Publications

Stakeholder analysis was first explored as a methodology to assist business leaders with their strategic management functions. Stakeholder analysis has since expanded beyond the corporate arena. Stakeholders are a vital element in all complex systems problems; they are the customers, users, clients, suppliers, employees, regulators, and team members of a system. They fund a system, design it, build it, operate it, maintain it, and dispose of it. Each stakeholder contributes their own value-added perspective, as described by the systems principle known as complementarity. While many approaches exist for classifying and determining their attitudes, these approaches stop short of evaluating stakeholders …

Reducing Uncertainty In Technology Selection For Long Life Cycle Engineering Designs, Halil I. Ozdemir, C. Ariel Pinto, Resit Unal, Charles B. Keating, Colin Britcher, Sila Çetinkaya (Ed.), J. K. Ryan (Ed.)

Engineering Management & Systems Engineering Faculty Publications

The best capabilities are usually achieved by having the latest technologies in defense systems. However, including the new, usually immature, technologies in a system design does not always easily result in achieving the capabilities at the right level, at an affordable cost, and in a timely manner. Many programs have suffered from immature technologies as cost overruns, late or no deliveries, and poor performance levels. Another impact of technology selection appears as obsolescence after the deployment of systems, or even before the deployment of the system. As the technologies of a system become obsolete, the cost of maintaining the system …

Challenges For Developing Complex System Governance, Charles B. Keating, Polinpaplinho F. Katina, Joseph M. Bradley, Sila Çetinkaya (Ed.), J. K. Ryan (Ed.)

Engineering Management & Systems Engineering Faculty Publications

This paper examines the challenges and practice implications for Complex System Governance (CSG). CSG is presented as an emerging field focused on the design, execution, and evolution of the higher order (metasystem) functions necessary to provide control, communication, coordination, and integration of a complex system. This paper is focused on three primary objectives. First, we introduce the complex system problem domain that the CSG field is being designed to address. The pervasiveness of this problem domain is demonstrated by a short examination of the water utilities sector. Second, we expound the nature of CSG and an emerging reference model …

Learning By Doing - Energy Systems Management, Nima Shahriari, Adrian V. Gheorghe

Engineering Management & Systems Engineering Faculty Publications

Climate change concerns have confronted energy policy makers by unprecedented challenges in the 21st century. Revolution of renewable energy technologies, as well as more efficient energy systems, has been promising in the context of global warming. However, these technologies are not maturing and chaning. Consequently planning for development of these resources requires dealing with various multidisciplinary research questions such as financial feasibility of renewable energy projects. Nevertheless, there is considerable lack of education programs offering multidisciplinary approach for addressing the current energy challenges. Based on the 21st evolving energy landscape, an interdisciplinary graduate certificate course work was designed at Old …

How System Errors Affect Aircrew Resource Management (Crm), Justin Y. Adkins, Kevin Macg. Adams, Patrick T. Hester

Engineering Management & Systems Engineering Faculty Publications

System errors, both mechanical and human in nature, can have a grave effect on aircrew judgement in flight. The effects of these errors can be massively compounded during emergency situations. Crew Resource Management (CRM) is an important process aircrews can utilize to minimize risks and enhance assessments. The employment of this technique can be validated by aviation mishaps over the last three decades and how system errors increased the probability of the incident occurring. Suggestions can be made to further prevent similar accidents from occurring in the future utilizing historical aeronautical records. This paper outlines an approach by which systems …

A Framework For Sustainable Material Selection For Multi-Generational Components, Ryan T. Bradley

Theses and Dissertations--Mechanical and Aerospace Engineering

The early stages of a product’s design are a critical time for decisions that impact the entire life-cycle cost. Product designers have mastered the first generation; however, they currently do not have the ability to know the impact of their decisions on the multi-generational view. This thesis aims at closing the gap between total life-cycle information and the traditional design process in order to harbor sustainable value creation among all stakeholders involved. A framework is presented that uses a combination of a life-cycle costing methodology and an evolutionary algorithm in order to achieve a sustainability assessment for a true multi-generational …

Systems Approach To Producing Electrospun Polyvinylidene Difluoride Fiber Webs With Controlled Fiber Structure And Functionality, Brian D. Bell

USF Tampa Graduate Theses and Dissertations

Polyvinylidene difluoride (PVDF) is a functional polymeric material that can be used for a wide variety of applications. There are many new future applications that were recently suggested for electrospun PVDF fibers. Electrospinning is a process capable of producing nano to micro sized PVDF fibers in a web. It is important to control the structure of the web during electrospinning because by controlling the structure of the web it is possible for the PVDF fiber web to have increased performance in comparison to other common forms of PVDF.

While past scientific literature focused on applications of PVDF fibers, little was …

Modeling Supply Chain Interdependent Critical Infrastructure Systems, Varun Ramachandran

Doctoral Dissertations

"While strategies for emergency response to large-scale disasters have been extensively studied, little has been done to map medium- to long-term strategies capable of restoring supply chain infrastructure systems and reconnecting such systems from a local urban area to national supply chain systems. This is, in part, because no comprehensive, data-driven model of supply chain networks exists. Without such models communities cannot re-establish the level of connectivity required for timely restoration of goods and services. This dissertation builds a model of supply chain interdependent critical infrastructure (SCICI) as a complex adaptive systems problem. It defines model elements, data needs/element, the …

An Agent Based Approach For Simulating Demo Enterprise Models, Mamadou Seck, Joseph Barjis

Engineering Management & Systems Engineering Faculty Publications

DEMO (design and engineering methodology for organization) is a theoretically grounded methodology for rigorous enterprise modeling. It provides relevant concepts from a construction perspective. As the methodology gains a wider audience, there is a growing interest in simulating DEMO models. Most attempts to develop a simulation approach for enterprise models in general, and the DEMO methodology in particular, are based on process oriented conceptualizations that are typically implementation in a discrete event paradigm. In this paper, we propose a conceptual framework for the translation of DEMO models into an agent based simulation. We will describe the DEMO methodology in some …

Bus Rapid Transit (Brt) Toolbox: Brt Person Throughput-Vehicle Congestion Tradeoffs, Li Jingquan, H.-S. Jacob Tsao, Ching-Yao Chan, Kun Zhou, Wei-Bin Zhang

Faculty Publications

This report documents a research effort to understand the current practice and issues associated with Bus Rapid Transit (BRT) planning and deployment. It reviewed the design options incorporated into existing BRT deployments across California and the nation. The project team interviewed practitioners of California Department of Transportation (Caltrans) Districts and transit agencies to understand the BRT project approval decision-making process, the impacts of BRT implementation and the Measures of Effectiveness (MOEs) for transit and non-transit system performance. The studies revealed that though Caltrans and transit agencies do use a similar set of MOEs for the evaluation of BRT projects, the …

A General Intuitive Design Pattern For Optimally Sequencing Treatment Combinations In 2k Factorial Experiment And A Simple Estimation Algorithm, H.-S. Jacob Tsao, Minnie Patel

Faculty Publications

The number of model parameters of a 2k factorial design grows exponentially. When the number of factors is large, numerous higher-order interactions constitute a vast majority of the model parameters while many of them do not exist or are insignificant. The classic methods of fractional factorial designs, Plackett–Burman designs, Taguchi designs, etc. seek an already developed and often cataloged design that fits exactly the problem being tackled or select a design that fits it the most. Most, if not all, of these designs were developed in absence of convenient computation tools and enjoy computational simplicity. The necessary number of treatment …

Safety Culture Monitoring: A Management Approach For Assessing Nuclear Safety Culture Health Performance Utilizing Multiple-Criteria Decision Analysis, James Harold Warren Jr.

Engineering Management & Systems Engineering Theses & Dissertations

Nuclear power plants are among the most technologically complex of all energy facilities. This complexity reflects the precision needed in design, maintenance and operations to harness the energy of the atom safely, reliably and economically. Nuclear energy thus requires consistent, high levels of organizational performance by the highly skilled professionals who operate and maintain nuclear power plants (Nuclear Energy Institute [NEI], 2014, p. 1).

A key element for achieving consistent, high levels of performance in a nuclear organization is its safety culture. Nuclear safety culture is for an organization what character and personality is for an individual: a feature that …

A Framework And System For A Multi-Model Decision Aid For Sustainable Farming Practices, Kasi Bharath Vegesana

Computational Modeling & Simulation Engineering Theses & Dissertations

Decision support systems (DSS) for farmers address the need for modeling multiple processes and scenarios that affect farmer decision making. Existing DSS have various drawbacks that stop them from being deployed as decision support tools. This research proposes a multi-model simulation framework that can be used to analyze farm management practices at the crop level, individual farm level and at the community level to show the impact and alternatives for smallholder farming practices. A generic crop growth model is proposed, based on existing equations. We run sensitivity analysis on the model to identify important variables. The outputs from the crop …

Quantum Inspired Algorithms For Learning And Control Of Stochastic Systems, Karthikeyan Rajagopal

Doctoral Dissertations

"Motivated by the limitations of the current reinforcement learning and optimal control techniques, this dissertation proposes quantum theory inspired algorithms for learning and control of both single-agent and multi-agent stochastic systems.

A common problem encountered in traditional reinforcement learning techniques is the exploration-exploitation trade-off. To address the above issue an action selection procedure inspired by a quantum search algorithm called Grover's iteration is developed. This procedure does not require an explicit design parameter to specify the relative frequency of explorative/exploitative actions.

The second part of this dissertation extends the powerful adaptive critic design methodology to solve finite horizon stochastic optimal …

Computational Intelligence Based Complex Adaptive System-Of-Systems Architecture Evolution Strategy, Siddharth Agarwal

Doctoral Dissertations

The dynamic planning for a system-of-systems (SoS) is a challenging endeavor. Large scale organizations and operations constantly face challenges to incorporate new systems and upgrade existing systems over a period of time under threats, constrained budget and uncertainty. It is therefore necessary for the program managers to be able to look at the future scenarios and critically assess the impact of technology and stakeholder changes. Managers and engineers are always looking for options that signify affordable acquisition selections and lessen the cycle time for early acquisition and new technology addition. This research helps in analyzing sequential decisions in an evolving …

Exploring Individual Differences In Workload Assessment, Danielle K. Boeke

Theses and Dissertations

Air Force missions continue to increase in complexity often imposing higher levels of task load from cognitive tasks on the operators. This increased task load manifests itself in increased cognitive workload and potentially derogated performance. While cognitive workload has been studied for decades, recent advances in objective workload models and physiology monitoring have the potential to provide a more robust understanding of workload, potentially allowing systems to adaptively employ automation to maintain operator peak performance. The current research sought to provide insight into the relationship between subjective workload, task performance, objective workload, and select physiology measures. Analysis of an existing …

A Decision Analysis Framework For Evaluation Of Helmet Mounted Display Alternatives For Fighter Aircraft, Matthew R. Dansereau

Theses and Dissertations

The promise of providing an intuitive and efficient information interface, while allowing the warfighter to perform other critical tasks such as targeting or aircraft control, has led to the growing popularity of Helmet Mounted Displays (HMDs) across the military landscape, especially combat aircraft. Though design and selection of competing systems is critical to optimized performance and safety, structured methods for the evaluation of HMDs are not often used in the acquisition community, leaving selection among alternative designs to the judgment of subject matter experts. However, technical decision-making has been shown to be flawed without the use of a structured decision …