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Full-Text Articles in Systems Science

An Innovative Hdm Model For Assessing Renewable Heat Energy Resources In Utility Energy Systems, Mark Alan Ryan Dec 2025

An Innovative Hdm Model For Assessing Renewable Heat Energy Resources In Utility Energy Systems, Mark Alan Ryan

Dissertations and Theses

Renewable Heat Energy projects exhibit numerous unique, complex, and often conflicting characteristics, including varying project sizes, diverse energy resources, stakeholder demands, and significant challenges in energy conversion applications. Traditionally, cash flow analysis and return on investment are the most widely recognized metrics for evaluating remote energy projects. However, numerous quantitative and qualitative factors influence the overall performance and success of Renewable Heat Energy System (RHES) projects. A comprehensive approach using advanced tools is essential for assessing the factors and criteria that significantly impact these projects.

This research investigates the key quantitative and qualitative factors that contribute to the successful implementation …


From Model To Behavior: Methodological Challenges In Using Fuzzy Cognitive Maps To Represent Mental Models, Catherine Elizabeth Moore Sep 2025

From Model To Behavior: Methodological Challenges In Using Fuzzy Cognitive Maps To Represent Mental Models, Catherine Elizabeth Moore

Dissertations and Theses

This dissertation examines the use of Fuzzy cognitive maps (FCMs) as representations of mental models and how these representations connect to individual behavior. Fuzzy cognitive maps (FCMs) are semi-quantitative models that encode cause-and-effect structures as directed graphs. They are frequently used to represent individuals' knowledge structures/mental models and should in theory correlate to actions and decisions of individuals; however, this correlation has yet to be explored in a systematic manner. This dissertation represents the first step in experimental research on the connection between FCMs and individual behavior. It examines two theories of how humans use mental models, one based on …


Emergence Of Norms In The Presence Of Social Network Structure In A Stochastic Evolutionary Game Theory Model, Parker Foresman Aug 2025

Emergence Of Norms In The Presence Of Social Network Structure In A Stochastic Evolutionary Game Theory Model, Parker Foresman

Dissertations and Theses

In their 2000 paper, The Emergence of Classes in a Multi-Agent Bargaining Model, Axtell, Epstein, and Young introduced an agent-based bargaining model to study how social norms can emerge and persist from the decentralized, asynchronous interactions of individual agents in the presence of noise, even when these agents have no predefined preferences or advantages. This thesis extends their model by incorporating structured interaction networks, allowing us to investigate how the topology of agent interactions influences long-run dynamics and norm formation. Using a custom simulation package built in the Julia programming language, we replicate the original results under a complete …


Five Pivotal Practices For Leaders To Cultivate Empathy Within Virtual Scrum Teams, Dahm Mongkol Hongchai, Charles M. Weber Aug 2024

Five Pivotal Practices For Leaders To Cultivate Empathy Within Virtual Scrum Teams, Dahm Mongkol Hongchai, Charles M. Weber

Engineering and Technology Management Faculty Publications and Presentations

In the digital and global economy, business leaders need more than just business and technology competencies; they also require empathy. However, there is a notable scarcity of research on empathy in Scrum for product development. This study aims to uncover critical insights into how leaders can foster empathy within virtual Scrum teams. Accordingly, this paper proposes five pivotal themes leaders can employ: Scrum fundamentals, meditation, self- and other-analysis, healthy interactions, and informal connections. These vital strategies offer actionable methods for leaders seeking to enhance empathy within their virtual Scrum teams.


Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Andrew Harris Feb 2023

Graphical Models In Reconstructability Analysis And Bayesian Networks, Marcus Andrew Harris

Dissertations and Theses

This research focuses on the investigation of two machine learning methodologies, Reconstructability Analysis (RA) and Bayesian Networks (BN). Both methods are probabilistic graphical modeling (PGM) methodologies. RA was developed in the systems community and has applications including time-series analysis, classification, decomposition, compression, pattern recognition, prediction, control, and decision analysis. BNs have origins in path models and have applications similar to those of RA. BNs are another graphical modeling approach for data modeling that is closely related to RA; where BN overlaps RA the two methods are equivalent, but RA and BN each has distinctive features absent in the other methodology. …


Systems Thinking Activities Used In K-12 For Up To Two Decades, Diana Fisher, Systems Thinking Association Feb 2023

Systems Thinking Activities Used In K-12 For Up To Two Decades, Diana Fisher, Systems Thinking Association

Complex Systems Faculty Publications and Presentations

Infusing systems thinking activities in pre-college education (grades K-12) means updating precollege education so it includes a study of many systemic behavior patterns that are ubiquitous in the real world. Systems thinking tools include those using both paper and pencil and the computer and enhance learning in the classroom making it more student-centered, more active, and allowing students to analyze problems that have been heretofore beyond the scope of K-12 classrooms. Students in primary school have used behavior over time graphs to demonstrate dynamics described in story books, like the Lorax, and created stock-flow diagrams to describe what was needed …


System Dynamics Modeling For Traumatic Brain Injury: Mini-Review Of Applications, Erin S. Kenzie, Elle L. Parks, Nancy Carney, Wayne Wakeland Aug 2022

System Dynamics Modeling For Traumatic Brain Injury: Mini-Review Of Applications, Erin S. Kenzie, Elle L. Parks, Nancy Carney, Wayne Wakeland

Complex Systems Faculty Publications and Presentations

Traumatic brain injury (TBI) is a highly complex phenomenon involving a cascade of disruptions across biomechanical, neurochemical, neurological, cognitive, emotional, and social systems. Researchers and clinicians urgently need a rigorous conceptualization of brain injury that encompasses nonlinear and mutually causal relations among the factors involved, as well as sources of individual variation in recovery trajectories. System dynamics, an approach from systems science, has been used for decades in fields such as management and ecology to model nonlinear feedback dynamics in complex systems. In this mini-review, we summarize some recent uses of this approach to better understand acute injury mechanisms, recovery …


Reducing Opioid Use Disorder And Overdose Deaths In The United States: A Dynamic Modeling Analysis, Erin J. Stringfellow, Tse Yang Lim, Keith Humphreys, Catherine Digennero, Celia Stafford, Elizabeth Beaulieu, Jack Homer, Wayne Wakeland, Multiple Additional Authors Jun 2022

Reducing Opioid Use Disorder And Overdose Deaths In The United States: A Dynamic Modeling Analysis, Erin J. Stringfellow, Tse Yang Lim, Keith Humphreys, Catherine Digennero, Celia Stafford, Elizabeth Beaulieu, Jack Homer, Wayne Wakeland, Multiple Additional Authors

Complex Systems Faculty Publications and Presentations

Opioid overdose deaths remain a major public health crisis. We used a system dynamics simulation model of the U.S. opioid-using population age 12 and older to explore the impacts of 11 strategies on the prevalence of opioid use disorder (OUD) and fatal opioid overdoses from 2022 to 2032. These strategies spanned opioid misuse and OUD prevention, buprenorphine capacity, recovery support, and overdose harm reduction. By 2032, three strategies saved the most lives: (i) reducing the risk of opioid overdose involving fentanyl use, which may be achieved through fentanyl-focused harm reduction services; (ii) increasing naloxone distribution to people who use opioids; …


Augmentative And Alternative Communication Use, Service Delivery Experiences, And Communicative Participation For People With Amyotrophic Lateral Sclerosis, Betts Peters Jun 2022

Augmentative And Alternative Communication Use, Service Delivery Experiences, And Communicative Participation For People With Amyotrophic Lateral Sclerosis, Betts Peters

Dissertations and Theses

People with amyotrophic lateral sclerosis (ALS) often experience changes to their speech, and may use augmentative and alternative communication (AAC) devices and techniques to maintain the ability to communicate. The use of AAC may facilitate the participation of people with ALS in various life situations involving communication. There is limited data in the literature about the AAC approaches currently used by people with ALS, the professional services they receive to support communication, or the effects of AAC on their communicative participation. This dissertation involved a nationwide online survey of people with ALS, and comprises three papers intended to add to …


The Role Of Feedback In The Assimilation Of Information In Prediction Markets, Richard Donald Jolly Jan 2011

The Role Of Feedback In The Assimilation Of Information In Prediction Markets, Richard Donald Jolly

Dissertations and Theses

Leveraging the knowledge of an organization is an ongoing challenge that has given rise to the field of knowledge management. Yet, despite spending enormous sums of organizational resources on Information Technology (IT) systems, executives recognize there is much more knowledge to harvest. Prediction markets are emerging as one tool to help extract this tacit knowledge and make it operational. Yet, prediction markets, like other markets, are subject to pathologies (e.g., bubbles and crashes) which compromise their accuracy and may discourage organizational use.

The techniques of experimental economics were used to study the characteristics of prediction markets. Empirical data was gathered …


Hardiness, Well-Being, And Health: A Meta-Analytic Summary Of Three Decades Of Research, Celina Marie Oliver Jul 2009

Hardiness, Well-Being, And Health: A Meta-Analytic Summary Of Three Decades Of Research, Celina Marie Oliver

Dissertations and Theses

In recent decades, as scientific understanding regarding the effects of stress on health and well-being has grown, researchers have shown increasing interest in personal factors such as hardiness that may enhance one's ability to remain resilient under stressful conditions. Hardiness is a complex trait composed of three components (commitment, control, and challenge) that combine synergistically to increase stress tolerance. Over time, a large and complex body of research has accumulated, and while many qualitative reviews have been conducted, quantitative summaries remain rare. This study provides an empirical synthesis of research findings examining the relationships between hardiness and correlates related to …


Modeling Subprime Mortgage Delinquency, Default, Prepayment And Loss, Olgay Cangur Apr 2009

Modeling Subprime Mortgage Delinquency, Default, Prepayment And Loss, Olgay Cangur

Dissertations and Theses

The current financial environment presents significant challenges for the mortgage industry. Declining house prices have surfaced the importance of delinquency, loan default and loss predictions. Simple models of prepayment behavior are no longer applicable. Investors, originators, servicers and regulators are in need of more accurate predictions for their portfolios of interest.

This dissertation focuses on two topics relevant to modeling residential mortgages. The first topic provides a framework for modeling delinquencies, prepayments, defaults and losses that represents an enhancement over previous studies. A total of nine loan payment statuses are used (current, thirty-days delinquent, sixty-days delinquent, ninety-days delinquent, early foreclosure, …


Determinants Of Cross Organizational Software Project Success, And Ozbay Feb 2009

Determinants Of Cross Organizational Software Project Success, And Ozbay

Dissertations and Theses

The importance of software development (SWD) has been rapidly increasing over the past few decades. As this industry has grown, there has been an increasing deployment of cross organizational (C/O) SWD (also called distributed development or global software development) projects. These C/O SWD projects have adversely impacted the already low success rates of SWD projects. Methods to address problems of C/O SWD projects are not available to SWD managers primarily because challenges that underlie C/O SWD are incompletely understood.

This dissertation explored the problems associated with C/O SWD in real-life contexts. Inductive case study research methods and grounded theory were …


More Than Screening Tools? : An Examination Of Preliminary Applicant Evaluation Methods, Matthew Eric Paronto Nov 2008

More Than Screening Tools? : An Examination Of Preliminary Applicant Evaluation Methods, Matthew Eric Paronto

Dissertations and Theses

The increased prevalence of technology in organizations has had significant impacts on the recruiting, screening, and hiring processes. However, little is known regarding whether preliminary applicant evaluation methods provide meaningful candidate information beyond possession of minimum qualifications. To address this gap in the literature, two preliminary applicant evaluation procedures used at a major utility company were examined across two separate studies.

Study 1 examined online applicant prescreening protocols across three positions. Archival prescreening data from 5,619 applicants were analyzed in terms of item characteristics that distinguished candidates at different points in the score distribution (high vs. low; highest vs. high), …


Role Of Food Neophobia, Food Attitudes And Written Information On The Acceptance Of Novel Fish Products : A Cross-Cultural Study, Koei Kudo Aug 2008

Role Of Food Neophobia, Food Attitudes And Written Information On The Acceptance Of Novel Fish Products : A Cross-Cultural Study, Koei Kudo

Dissertations and Theses

The present research used an integrative and multi-disciplinary approach to investigate the relations among food attitudes, food neophobia and acceptance of novel and familiar albacore tuna dishes for Japanese and U.S. consumers.

A pilot study selected seasonings and cooking methods that were familiar or novel to each culture, and identified the most relevant health benefits of omega-3 fatty acids (FA).

The main study employed a self-reported, web-based questionnaire where back-translation maximized the cross-cultural equivalency of US and Japanese versions. Scales of food neophobia (Crystallized Neophobia Scale, or CNS) and attitudes towards foods (Health-, Pleasure- and Convenience-Oriented Food Attitudes Scale, or …


Developing A Sense Of Academic Ownership : A Longitudinal Analysis, Gwen Catherine Marchand Jul 2008

Developing A Sense Of Academic Ownership : A Longitudinal Analysis, Gwen Catherine Marchand

Dissertations and Theses

Student responsibility has emerged as a key developmental task, particularly during the transition to middle school. A developmental and motivational perspective was taken for the present study that emphasized agency, ownership, and engagement as key parts of the development of student responsibility. Self-determination Theory (SDT) was selected as the overarching framework for the present investigation due to the theory's emphasis on autonomy, which refers to the experience of oneself as the authentic origin of one's own actions (Deci & Ryan, 1985). In SDT, the construct of autonomy is used to integrate views of intrinsic and extrinsic motivation and to differentiate …


Intimate Partner Violence, Supervisor Support And Work Outcomes For Low-Wage Workers, Nanette Lucia Yragui Jun 2008

Intimate Partner Violence, Supervisor Support And Work Outcomes For Low-Wage Workers, Nanette Lucia Yragui

Dissertations and Theses

The workplace is a setting where women in abusive relationships can potentially access information and support to resolve the violence in their lives. This study addresses a critical need for data-based knowledge about how supervisors can effectively support employees experiencing intimate partner violence. The dissertation study examines supervisor support congruency (i.e., the match between support wanted and received) and work outcomes for Latina and non-Latina, abused women. Specifically, I examine which supervisor support measures best predict work outcomes for abused, low-wage, employees. In addition, I evaluate the criterion validity and reliability of a behavioral measure of wanted and received supervisor …


A Grounded Agent Model Of The Consumer Technology Adoption Process, Brent Alan Zenobia Jun 2008

A Grounded Agent Model Of The Consumer Technology Adoption Process, Brent Alan Zenobia

Dissertations and Theses

Adoption is one of the most important concepts in the diffusion of innovations (DOI) literature, yet certain aspects of it are poorly understood. In particular, causal adoption process theory (CAPT) has been stagnant for decades and seldom subjected to critical scrutiny. In consequence, DOI research is unstable – different studies identify different factors as important.

This dissertation introduces grounded agent modeling, a hybrid methodology drawing on existing software engineering and social science techniques to construct a step-by-step explanation of how consumers make technology adoption decisions. Inductive case studies, grounded theory, and sequence analysis are used to investigate transportation mode adoption …


Moving Up The Cmmi Capability And Maturity Levels Using Simulation, David Raffo, Wayne Wakeland Jan 2008

Moving Up The Cmmi Capability And Maturity Levels Using Simulation, David Raffo, Wayne Wakeland

Complex Systems Faculty Publications and Presentations

Process Simulation Modeling (PSIM) can be used to evaluate issues related to process strategy, process improvement, technology and tool adoption, project management and control, and process design. It is a flexible tool and can aid in quantitatively testing ideas about how to configure a process or how to configure a software acquisition supply chain (consisting of contractors and sub-contractors) that would be too expensive or too risky to construct and evaluate in any other manner.

Recent developments in PSIM tools have drastically cut the costs of developing models to evaluate process issues. Moreover, new models and more systematic and repeatable …


Prediction Of Traditional Chinese Medicine Diagnosis From Psychosocial Questionnaires, Scott David Mist Oct 2007

Prediction Of Traditional Chinese Medicine Diagnosis From Psychosocial Questionnaires, Scott David Mist

Dissertations and Theses

Astonishingly, most Traditional Chinese Medicine (CM) research in the West proceeds without CM diagnoses, perhaps because CM diagnosis is time consuming or not considered relevant. One way to improve the feasibility of incorporating CM diagnosis would be to prescreen participants using questionnaires. This would allow cost savings in recruitment, and balancing of treatments by CM diagnosis. Consequently, the hypothesis of this research was that pre-treatment questionnaires can predict CM diagnosis.

Baseline questionnaires from 195 participants with temporomandibular joint disorder (TMD) were examined to test the hypothesis. Two methods, logistic regression (LR) and reconstructability analysis (RA), were used in conjunction to …


Shift Work In The Long-Termcare Industry : An Examination Of Organizational And Individual Factors That Influence Employee Outcomes, Kristin Elizabeth Charles Aug 2007

Shift Work In The Long-Termcare Industry : An Examination Of Organizational And Individual Factors That Influence Employee Outcomes, Kristin Elizabeth Charles

Dissertations and Theses

The long-term care (LTC) industry provides medical and social services in facility-based settings to the elderly, chronically ill, and disabled. With the aging of the United States population, the need for LTC workers is expected to drastically increase in the next decade. However, the industry faces a significant staffing shortage. One potential cause of staffing problems in LTC is working non-standard work schedules. Because of the need to provide around the clock care, LTC employees often work non-standard shifts, long hours, night work, and over weekends and holidays. Although many studies have examined health and sleep-related outcomes associated with non-standard …


Sensitivity Analysis For Hierarchical Decision Models, Hongyi Chen Jun 2007

Sensitivity Analysis For Hierarchical Decision Models, Hongyi Chen

Dissertations and Theses

In this dissertation, a comprehensive algorithm is developed to analyze the sensitivity of hierarchical decision models (HDM), which include the well-known analytic hierarchy process (AHP) and its variants, to single and multiple changes in the local contribution matrices at any level of the decision hierarchy. The algorithm is applicable to all HDM that use an additive function to derive the overall contribution vector. It is independent of pairwise comparison scales, judgment quantification techniques and group opinion combining methods. The direct impact of changes to a local contribution value on decision alternatives' overall contributions, allowable range/region of perturbations, contribution tolerance, operating …


Improving Monitoring And Diagnosis For Process Control Using Independent Component Analysis, Thaddeus Taylor Shannon May 2007

Improving Monitoring And Diagnosis For Process Control Using Independent Component Analysis, Thaddeus Taylor Shannon

Dissertations and Theses

Statistical Process Control (SPC) is the general field concerned with monitoring the operation and performance of systems. SPC consists of a collection of techniques for characterizing the operation of a system using a probability distribution consistent with the system's inputs and outputs. Classical SPC monitors a single variable to characterize the operation of a single machine tool or process step using tools such as Shewart charts. The traditional approach works well for simple small to medium size processes. For more complex processes a number of multivariate SPC techniques have been developed in recent decades. These advanced methods suffer from several …


A Multilevel Analysis Of Individual And Organizational-Level Effects On Staff Attitudes Towards Use Of Medication In Substance Abuse Treatment, John Patrick Fitzgerald Apr 2007

A Multilevel Analysis Of Individual And Organizational-Level Effects On Staff Attitudes Towards Use Of Medication In Substance Abuse Treatment, John Patrick Fitzgerald

Dissertations and Theses

Studies consistently indicate a general lack of support for use of medications in the treatment of substance abuse disorders by clinicians, patients, and other stakeholders involved in treatment. Both individual and organizational factors have been shown to influence attitudes towards medications, but the relative contribution of each of these factors remains unclear. Whereas previous studies, by their very design, have generated multilevel data structures, they nevertheless have employed analytic strategies that ignore the multilevel dependencies inherent in such data sets.

To address these limitations, this study took a multilevel approach to investigate the influence of individual and organizational factors on …


A Market-Based Framework For Semiconductor Industry Growth The Reduced Ecological Impart, Dawood Sulieman Abugharbieh Jun 2006

A Market-Based Framework For Semiconductor Industry Growth The Reduced Ecological Impart, Dawood Sulieman Abugharbieh

Dissertations and Theses

Reducing the ecological impact of industrial development is an emerging trend that affords companies the opportunity to gain competitive advantage. Semiconductor manufacturers have specifically identified ecological impact as a strategic variable that presents a long-term challenge. The socioeconomic nature of the ecological impact construct increases decision-making complexity in a manner that is not typical in business-to-business contexts. To account for social and economic aspects, this study utilized a cognitive structure-based model. Such models have been successfully utilized in consumer and industrial markets as adaptable frameworks that can encompass social and economic constructs.

This research focuses on linking two ecological constructs …


Early Moral Sense : Behavioral Self-Regulation, Temperament, And Prosocial Behavior In Young Children In Child-Centered Classrooms, Elizabeth Alliene Vale May 2006

Early Moral Sense : Behavioral Self-Regulation, Temperament, And Prosocial Behavior In Young Children In Child-Centered Classrooms, Elizabeth Alliene Vale

Dissertations and Theses

Development of moral sense is a fundamental part of human development and the earliest manifestations of moral sense are of particular interest because it may be important to foster these behaviors early in life. However, despite many important discoveries about these moral sense behaviors over the last several decades, no consensus exists as to how these behaviors emerge and differ as a function of age.

The primary goal of the current research was to explore the development of multiple behaviors that reflect moral sense in very young children, aged 4 to 36 months. More specifically, the goals were: (1) to …


Job Insecurity And Work-Family Conflict: The Organizational, Situational, And Individual Influences On The Job Strain Process, Khatera Sahibzada May 2006

Job Insecurity And Work-Family Conflict: The Organizational, Situational, And Individual Influences On The Job Strain Process, Khatera Sahibzada

Dissertations and Theses

Globalization, new technologies, downsizing, and a shift from manufacturing to service-based economies have led to an increase in job insecurity, resulting in deleterious effects on employee work attitudes and behaviors. However, the literature has failed to examine the impact of job insecurity on work-family outcomes. Therefore, the purpose of the present study was to examine the relationship between job insecurity and work-family conflict. The specific research questions addressed were: (a) does job strain mediate the relationship between job insecurity and work-family conflict? and (b) is the relationship between job insecurity and work-family conflict moderated by individual, situational and organizational perceptions? …


First Impressions : A Study Of The Relationship Between Presenting Problems And Clinical Perception, Holly Elizabeth Fussell May 2006

First Impressions : A Study Of The Relationship Between Presenting Problems And Clinical Perception, Holly Elizabeth Fussell

Dissertations and Theses

Processes involved in clinical perception typically result in tangible outcomes of interest to clients and practitioners (e.g., diagnoses). In developing an overall impression of clients, practitioners integrate information related to target problems clients present. Substance abuse counselors, in particular, are increasingly being asked to assess clients for co-occurring problems. Domestic violence has been identified as a particularly salient co-occurring problem associated with substance abuse.

This dissertation draws on theory by Solomon Asch (1946, 1952) to examine how presenting problems such as domestic violence shape clinical outcomes and processes in substance abuse assessment interviews. Most clinical interactions occur, however, under confidential …


Interpersonal Sensitivity And Information Sharing During Layoffs: Implications For Job Seekers, Rainer Seitz Apr 2006

Interpersonal Sensitivity And Information Sharing During Layoffs: Implications For Job Seekers, Rainer Seitz

Dissertations and Theses

Layoffs have become an increasingly common cost reduction strategy implemented by organizations. In addition to affecting those who lose their jobs or remain with the organization after a reduction, layoffs may also affect individuals outside the organization. A systems perspective on layoffs takes into account the various stakeholders who are affected by such an action beyond those traditionally studied. Job applicants are one group of stakeholders for which research on the implications of layoffs is lacking. The purpose of this dissertation was to examine the specific organizational justice factors of interpersonal sensitivity and information sharing in a layoff and their …


A Decision Model For Technology Assessment To Reduce The Internal Digital Divide In Emerging Economies (Case: Costa Rica), Audrey MaríA Alvear BáEz Apr 2005

A Decision Model For Technology Assessment To Reduce The Internal Digital Divide In Emerging Economies (Case: Costa Rica), Audrey MaríA Alvear BáEz

Dissertations and Theses

Information and Communication Technologies (ICTs) such as Wireless, the Internet, and e-commerce software are profoundly impacting how business and government are conducted. Digital divide (DD) refers to the gap that opens up between those who have access to, benefit and interact with ICTs and those who can not. ICTs can either accelerate change and thereby increase the DD in developing countries, or, if deployed carefully can be a tool to reduce the DD within a country. This study presents a systematic approach for doing the latter by identifying the ICTs, technology applications and key sectors that most impact the internal …