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OPTIMAL STRATEGIES FOR ENHANCING AND MAINTAINING CRITICAL INFRASTRUCTURE CAPACITY IN DISASTERS
Get PDFCritical societal services such as health care, education, law enforcement, and emergency response, are key to community well-being impacting the health of population, society economics and safety of the community. These services are at risk of failure from disasters either directly through damage to the buildings or indirectly as a result of disruption to lifelines that support these services. This dissertation aims to find optimal strategies and identification of targeted actions for enhancing and maintaining critical infrastructures (CIs) and CI system capacity and capability post-disaster in times of recovery. More specifically, this dissertation proposes mathematical models and solution algorithms as well as simulation-based methods to provide broader insights that will benefit decision- and policy-makers in preparation for emergency response. This dissertation contributes to the body of literature in obtaining optimal strategies through following: (1) Expanding a Discrete-Event Simulation model of a generic 200-bed urban U.S. tertiary hospital, simultaneously caring for pandemic and routine emergency patients to provide generalizable insights into how hospital functionality may be affected by the care of pandemic patients as well as estimating a maximum regional capacity to serve pandemic patients requiring hospital services during a surge before requesting external sources. (2) Proposing a multi-stage stochastic program with decision-dependent uncertainty to jointly devising post-disaster inspection and restoration actions with the goal to minimize roadway downtime and maximize opportunities for timely completion of repairs to other lifelines (e.g. power) over the recovery period (3) Developing a mathematical formulation for the problem of prioritizing critical societal services given their reliance on multiple interdependent lifelines and proposing an exact algorithmic approach for its solution. Investigating two developed acceleration approaches for use in realistic settings, where efficiency and scalability are important. (4) Providing a mathematical formulation for the problem of restoration scheduling of lifelines given their dependencies on hard and soft infrastructure with implementing an exact solution framework to recognizing the role of people in multiple interdependent infrastructure system recovery. In summary, these analytical tools provide modeling capabilities and broader insights for stakeholders to better respond to disaster and be able to enhance the capacity of CIs and CI system that the community greatly rely on
Placemaking and Identity: An Examination of Men-Who-Have-Sex-With-Men in Public
Get PDFIn the United States, public life is regulated and dominated by heteronormativity, which in turns pushes out and oppresses individuals that live non-heterosexual lives. One such marginalized group is Men-Who-Have-Sex-With-Men (MSM) who are, often, heterosexual men who engage in same-sex relations. MSM can engage in homosexual acts with one another without questioning their heterosexual identity. In this thesis, I explore this seeming contradiction by analyzing Seeker.com, a website utilized by MSM to find others with whom to engage in public sex. I offer possible explanations for these men's ability to engage non-heteronormative acts while also maintaining their position in the heterosexists public. I then show the ways MSM, through their use of public space, reframe logics passed to them through the heteronormative experience to create a counter public space. My hope is that by examining MSM's unique positionality, we may see the multitude of ways that groups and individuals reframe themselves in public places while also challenging heteronormative social spaces
Exploration of the multilevel and temporal intricacies of emergent states in multiteam systems
No full textThis work is embargoed by the author and will not be publicly available until May 2028.A growing body of research has established multiteam systems (MTSs) as having a distinct organizational structure that pose unique collaboration challenges and thus are worthy of scholarly pursuit. While highlighted as an integral component of addressing these collaboration challenges, few MTS studies have explored how multilevel emergent states -- constructs that arise from lower-level entities and change over time -- form and evolve within component teams and across the system. This research poses several research questions to abductively explore how multilevel emergent states form and evolve in MTSs. Study 1 assessed multilevel emergent states in three sail training squadron MTSs over their lifespan. Based on Study 1’s findings a set of propositions were developed and used to inform the development of an agent-based model of MTS emergent states. Several virtual experiments were conducted to examine underlying generative mechanisms proposed to explain the patterns of emergent states found in MTSs. This paper concludes with a discussion that focuses on implications of the MTS emergent state theory by offering refined propositions that can be used to spark future MTS research.2028-05-1
Undermining Motivations in Reading: An Exploratory Study with High School Students
Get PDFThe focus of this study was the construct of undermining motivation, specifically for reading. Because motivation plays an important role in a student’s academic performance, it is important for schools and teachers to be aware of the experiences of students experiencing undermining motivations. Research has not only shown that many actions spurred by undermining motivations can be detrimental to student academic achievement, but also that motivation is important to student learning. However, comparatively little of the research on motivation has been done at the high school level even though motivation, specifically a student’s sense of autonomy, competence and belonging, can impact their classroom experiences; fewer still are the studies that directly feature student voices. This qualitative study solicited student voices to examine undermining motivations for reading in public high school students. The student participants completed an informational questionnaire, which asked students to select a pseudonym of their choice and to share their initial ideas about reading and undermining motivations. Subsequently we discussed their experiences. Finally, they crafted their own stories in the genre of their choice inspired by their brainstorming. We also reflected upon those stories. Data were coded and analyzed using MAXQDA software. Students shared their appraisals of structural demotivators, relational demotivators, and of self. The results were used to refine a model of undermining motivation which demonstrated the interactions of undermining motivations with student actions and perceptions. I also crafted a proposed definition of the construct undermining motivation: “The emotions, actions, and structures that influence or interfere with the instigation and sustainment of goal-directed activities.
CORROSION OF ADDITIVE MANUFACTURED STAINLESS STEEL 304L
Get PDFThis work is embargoed by the author and will not be publicly available until December 2025.Additive manufacturing (AM), as one of the notable methods in manufacturing of metal parts, yields some unique microstructural and defect features which may alter the metal’s corrosion behavior. Although there have been major strides in understanding the impact of AM process on mechanical properties such as tensile and fatigue, the understanding of the corrosion properties of AM metals and alloys remains in its infancy. Due to complexity of interaction between corrosion and microstructure and defects in AM metals, there exist numerous knowledge gaps in understanding such interactions and there is the need for significant future works to realize the full potential of AM technologies in real world applications. In this research, multiscale corrosion testing and evaluation techniques are used to understand the interplay of materials microstructure and defects with corrosion properties of AM stainless steel 304L. Further, the interplay of stress and corrosion triggers an electro-chemo-mechanical interaction, influencing corrosion mechanisms thermodynamically and kinetically. Localized strains significantly impact surface reactivity, passivity breakdown, and repassivation in AM stainless steel 304L under monotonic and fatigue loading. This research highlights new findings of the effects of monotonic and fatigue loading on corrosion in wrought stainless steel 304L. The results of this research offer new and exciting research in the field of corrosion of AM metals for the years to come.2025-12-1
Sobre la vergüenza en nuestros tiempos: conciencia, interdependencia y trascendencia en la historia de la humanidad
No full textEsta sesión busca hablar sobre la construcción histórica y cultural del sentimiento de vergüenza, así como de los significados que ésta ha tenido en diferentes momentos y circunstancias históricas. Habla, también, de las diferencias entre la culpa y la vergüenza, así como de la relación entre emoción, cuerpo y experiencia
#COVID-19 Searching for a Relationship between Twitter Sentiment and Infectious Disease
Get PDFDigital health data such as social media data has shown potential for identifying outbreaks faster than official records of disease incidence. The objective of this thesis 1 is to examine the relationship between COVID-19-related Tweet sentiment and COVID-19 cases over space and time and assess the extent to which Twitter-derived sentiment can be used for local COVID-19 surveillance in the United States. To our knowledge, there is no existing study that examines the relationship between Tweet sentiment and infectious disease cases at a spatially local level. The sentiment is computed using 56,755,894 Tweets from the TBCOV dataset for US counties over time. Tweet sentiment is examined with COVID-19 cases for each county globally, over time, and space using Pearson's R correlation. A negative association was observed between COVID-19 cases and the sentiment polarity of COVID- 19 tweets, but only in some regions of the US and only for some duration of the period of study. Further research is needed to understand the cause of the spatial and temporal non-stationary correlations between Twitter sentiment and COVID-19 cases. This would allow for the identification of when and where Twitter sentiment could be used as a signal for early disease outbreak warning
(Dys)functional Academies: Social Accessibility in Higher Education
Get PDFA mixed-methods, two-part study was deployed exploring experiences of students with disabilities at George Mason University. The first part of the study involved a quantitative survey of student attitudes towards persons with disabilities and a series of fairness questions targeting how fair students felt their disabled peers' accommodations were. The second part of the study involved structured, written interviews centering the experiences of students with disabilities. The hypothesis of the quantitative study was that there would be a correlation between more negative attitudes towards persons with disabilities and increased perception of accommodations being unfair. This hypothesis was partially supported. The qualitative portion of the study was more exploratory in nature, analyzed for trends across six domains—background and general experiences with disability, positive experiences, negative experiences, disclosure, academic effects, and general quality improvement questions regarding use of services offered by Office of Disability Services
Digital Twin-Based Optimization with Predictive Simulation Learning
Get PDFAcross domains and practices, computer simulations are a common tool that engineers, economists, decision makers, and others utilize to project real world impacts we might realize from controllable systems interacting with users and their environments. Simulations are preferable over other quantitative modelling methods when the relationship between systems, users, environments, and measurable outcomes is extremely complex, which almost always involves some aspect of randomness. While simulations give us the capability to quantitatively model these complex interactions, running these models requires a large amount of computational overhead. In fact, simulations may be precluded from use because this overhead is too large, where “too large” implies that the level of certainty in the observed model output required cannot be achieved in the time allotted for the given decision using the physical resources available. When the time constraints of the user cannot be accommodated by the simulation to execute enough replications to yield a solution that is at the precision required, the simulation cannot be effectively leveraged for decision making. The research presented in this dissertation seeks to find ways to reduce the computational overhead required by simulations to achieve a given level of output precision. A general class of algorithms referred to as simulation optimization algorithms addresses these issues, and the primary contribution of this research is the introduction of three novel simulation optimization algorithms; the Sequential Allocation using Machine-learning Predictions as Light-weight Estimates (SAMPLE) algorithm, the Robust Optimal Sampling (ROS) algorithm, and the Epsilon Optimal Sampling (EOS) algorithm. The algorithms introduce new ways to achieve better computational results when running simulations by integrating low-fidelity machine learning estimates with on-line simulation observations
Creative Dissolution: A Sociology of Self Undoing
Get PDFThis work is embargoed by the author and will not be publicly available until May 15, 2025.Typically described in mainstream narratives as an expanding “mental health crisis”, this study locates emergent, historically specific patterns of inner disturbance within the social landscape of the ongoing knowledge regime. Recognition of the epistemic blinders of scientific materialism enables diagnosis of what appears to be a globally dispersed social problem of psychic dimensions. Based in ethnographic and interview-centered data, research findings indicate that a historic ‘crisis of consciousness’ is afoot. This analysis positions ayahuasca as a medicine for these times, focusing on the social phenomena underlying resurgent interest in the therapeutic utility of psychedelic treatment protocols. The diasporic expansion of ceremonial ayahuasca practices can be understood as, in part, due to the plants’ efficacy in intervening in a contemporary psycho-spiritual dilemma. The plant medicine is observed in its unique capacity to mitigate inner distortion effects brought about by scientific materialism’s tendency to normalize the psychic disposition of a mechanistic worldview. With the assistance of a plant intelligence, the social subject of the prevailing episteme is enabled to obtain relief in the act of ‘seeing’ beyond its former state of rationalistically-conditioned perception limitation. This analysis thus places ayahuasca’s medicinal value in direct relation to its capacity to initiate an inner paradigm shift, as well as to assist the contemporary subject in reconfiguration of its relationship to the concept of knowledge itself. The study is not about ayahuasca, per se. Rather, it is about what ayahuasca can reveal about the limitations which have been placed upon human consciousness in these times.2025-05-1