Doctor of Philosophy, The Ohio State University, 2007, Electrical Engineering

Flow control refers to the ability to manipulate fluid flow so as to achieve a desired change in its behavior, which offers many potential technological benefits, such as reducing fuel costs for vehicles and improving effectiveness of industrial processes. An interesting case of flow control is cavity flow control, which has been the motivation of this study: When air flow passes over a shallow cavity a strong resonance is produced by a natural feedback mechanism, scattering acoustic waves that propagate upstream and reach the shear layer, and developing flow structures. These cause many practical problems including damage and fatigue in landing gears and weapons bays in aircrafts. Presently there is a lack of sufficient mathematical analysis and control design tools for flow control problems. This includes mathematical models that are amenable to control design. Recently reduced-order modeling techniques, such as those based on proper orthogonal decomposition (POD) and Galerkin projection (GP), have come to interest. However, a main issue with these models is that the effect of boundary conditions, which is where the control input is, gets embedded into system coefficients. This results in a form quite different from what one deals with in standard control systems framework, which is a set of ordinary differential equations (ODE) where the input appears as an explicit term. Another issue with the standard POD/GP models is that they do not yield to systems that have any apparent structure in their coefficients. This leaves one with little choice other than to neglect the nonlinearities of the models and employ standard linear control theory based designs. The research presented in this thesis makes an effort at closing the gaps mentioned above by 1) presenting a reduced-order modeling method utilizing a novel technique for input separation on POD/GP models, 2) introducing a technique based on averaging theory and center manifold theory so as to reveal certain struct (open full item for complete abstract)

Committee: Andrea Serrani (Advisor) Subjects:

PhD, University of Cincinnati, 2024, Engineering and Applied Science: Electrical Engineering

Controller design for adversarial dynamic systems has applications in robotics, aerospace, economics, biology, and warfare. Oftentimes, an optimal control strategy for the agent of interest is calculated by assuming a control strategy for the adversary and optimizing against the assumed strategy. However, control strategies developed using this approach are only viable if the adversary adheres to its assumed control strategy. To develop more robust control strategies, the adversarial scenario can be posed as a differential game. Differential game theory is a mathematical framework to simultaneously calculate equilibrium control strategies for both sides of an optimization problem. While differential game theory is a powerful tool, equilibrium control strategies can only be determined by calculating the global solution to the differential game, which often requires solving for singular surfaces. Singular surfaces occur in regions where the developed first-order equilibrium conditions breakdown. Solving for singular surfaces is a challenging, non-intuitive process that requires the development and utilization of analytical and numerical techniques. My research has primarily focused on developing numerical techniques to solve for singular surfaces within the global solutions of differential games. The developed techniques include a generalized coupled shooting method for determining non-linear dispersal surfaces; a non-linear programming problem to determine boundaries between singular surfaces; and the development of a multi-point boundary value problem to calculate solutions with regular and singular arcs. The developed methods are generalized for optimal control problems and differential games with various system complexities. In order to verify the validity and utility of these methods, equilibrium controllers for an automatic target recognition game are developed and numerically synthesized using the developed numerical methods. The numerical controller sy (open full item for complete abstract)

Committee: Zachariah Fuchs Ph.D. (Committee Chair); John Gallagher Ph.D. (Committee Member); Braham Himed Ph.D M.A B.A. (Committee Member); Dieter Vanderelst Ph.D. (Committee Member); Ali Minai Ph.D. (Committee Member) Subjects: Electrical Engineering

Master of Arts (MA), Bowling Green State University, 2024, Sociology

A recent report released by the Yale Program on Climate Change Communication and the George Mason University Center for Climate Change Communication found that only 61% of Americans believe that “global warming is mostly human-caused.” Moreover, a recent analysis from the Center for American Progress (2021) uncovered that 139 elected officials in the 117th Congress do not endorse or express concerns about the scientific validity of anthropogenic climate change. However, Powell (2017) examined 11,602 peer-reviewed articles examining anthropogenic climate change and found 100% consensus from the world's leading scientists. Few studies have applied a theoretical perspective rooted in criminology to quantitatively analyze why individuals deny anthropogenic climate change. To address this gap in the research, I apply Gottfredson and Hirschi's (1990) theory of self-control to anthropogenic climate change beliefs (ACCB). Additionally, I test whether education moderates the relationship between self-control and ACCB. This exploratory research employed original data collection by sampling respondents from CloudResearch's Connect platform in 2023 (n = 648). Results from the multivariate analyses show that self-control is not significantly associated with ACCB, nor does education moderate the relationship between self-control and ACCB. However, a significant association (p < .001) between Akers' (1998) social learning theory and ACCB was uncovered. Further research should analyze the four core elements (i.e., differential association, definitions, differential reinforcement, and imitation) of Akers' (1998) social learning theory to better understand the intricacies and drivers of these learned beliefs.

Committee: Thomas Mowen Ph.D. (Committee Chair); John Boman Ph.D. (Committee Member); Stephen Demuth Ph.D. (Committee Member) Subjects: Sociology

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2023, Sociology

While the field of criminology has focused on turning points that could shift individuals away from crime, little research has examined how criminal offending shapes sexual behaviors, adult relationships, and achieved fertility. Those involved in criminal activity arguably could face worse outcomes in these behaviors, largely due to considerations of labeling theory, where stigma could result in difficulty finding relationship partners. Certain types of crime may also be more stigmatizing than others, making one less desirable as a partner. This effect may be gendered in nature, such that certain types of crime may be more damaging for women as opposed to men. My project draws on criminology literature on labeling theory, the age-graded theory of social control, and social homogamy to predict numerous sexual, relationship, and fertility outcomes. Using Waves I, III, and IV of the National Study of Adolescent to Adult Health (Add Health), the following studies examine the impact of criminal activity on a variety of risky sexual behaviors, relationship type, and fertility outcomes. I find that both types of crime predict a younger age at first sex and more opposite-sex partners, though gender differences exist in how well the mechanisms included explain these relationships. While property crime initially decreases early union risk for women, this type of criminal behavior increases early union risk for men. Violent crime decreased early union risk for both gender groups, but the relationship only remained significant for women. Violent crime decreased the odds of Multiple-Partner Fertility (MPF), but only in reference to Single-Partner Fertility (SPF). Overall, linkages existed between the outcomes of all three studies.

Committee: Danielle Kuhl Ph.D. (Committee Chair); Lee Nickoson Ph.D. (Other); Karen Benjamin Guzzo Ph.D. (Committee Member); Stephen Demuth Ph.D. (Committee Member); Thomas Mowen Ph.D. (Committee Member) Subjects: Criminology; Sociology

Doctor of Philosophy, The Ohio State University, 2023, Mechanical Engineering

There has been increasing incorporation of connectivity and automation into systems that have been traditionally isolated and mechanical. In applications ranging from transportation to manufacturing, these large, interconnected systems are increasingly being tasked to perform several safety-critical functions. Considering the widespread implementation of these systems and increasing reliance on them, they have also become prime targets for malicious actors. In such scenarios, it is essential to develop and test systems to ensure safety and security right from the design stage of the product development cycle. This dissertation is an effort to develop tools and methodologies towards this goal. Given the scale of modern connected and autonomous systems, it is impossible to have a single solution for the entire system. To achieve the goals of this thesis, we split our study to target specific challenges seen at the network level, at the controller level, and in testing and validation. We draw from the fields of game theory, control theory, and optimization to address issues in network design, safe control synthesis, and safety validation of connected and autonomous vehicles. We begin by studying the problem of improving network level security when the network defender has a restricted budget for fortifying and protecting the network assets. We consider scenarios where the defender, in addition to making optimal decision on where to allocate the limited security budget, can also intervene and modify the design of the network to strengthen it against attacks. We first propose algorithms to decide on the optimal allocation of the security budget across large inter-connected networks, by first reducing them to equivalent networks of lower dimensionality, in a way that enables faster computation of defense decisions. We further study various network design interventions to improve network security, and showcase our proposed approaches by applying them on practical a (open full item for complete abstract)

Committee: Qadeer Ahmed (Advisor); Giorgio Rizzoni (Committee Member); Parinaz Naghizadeh (Committee Member) Subjects: Mechanical Engineering

Master of Arts (MA), Bowling Green State University, 2020, Mathematics

Control and estimation theory are branches of mathematics that involve using data and measurements to estimate the value of a parameter of interest, and how changing certain parameters effects this estimation. The Kalman filter is a fundamental result in control and estimation theory that was introduced by Rudolf E. Kalman in 1960. The Kalman filter is a set of equations that provides an optimal estimate of the state of a system in a least-squares sense. The filter is often sought for its recursive and noise-smoothing properties, and has been found useful across many disciplines and in real world systems. This thesis will contribute to the literature of control and estimation theory by providing an introduction to the principles of the filter. This introduction includes a brief history of the filter, a derivation of the filter equations, and simple examples of applications of the filter.

Committee: Kit Chan Dr. (Advisor); So-Hsiang Chou Dr. (Committee Member) Subjects: Mathematics

PhD, University of Cincinnati, 2019, Education, Criminal Justice, and Human Services: Criminal Justice

Based on Gottfredson and Hirschi's (1990) general theory of crime, research has shown that low self-control is a consistent and significant predictor of criminal behavior, with general effects across diverse contexts and populations. Starting with the path-breaking work of Schreck (1999), this perspective has been used to explain not only criminal involvement but also crime victimization. Research for two decades has revealed that low self-control has general effects on victimization across both domestic and international contexts. Extant international studies of the theory, however, have been undertaken in nations similar in culture and economy to the United States. To address this limitation, the current project tests the generality thesis of low self-control in the notoriously private and under-studied country of Saudi Arabia. Because its culture, values, and social structure vary greatly from those of the United States, demonstrating significant effects of low self-control in Saudi Arabia would speak strongly to the general effects of low self-control, regardless of social context. Notably, beyond the low self-control perspective, lifestyle-routine activity theory (L-RAT) has demonstrated significant predictive ability in explaining victimization. Given L-RAT's prominence, the current project also examines the effects of L-RAT measures on the victimization experiences of Saudi youths. These analyses thus assess the robustness of low self-control as a source of victimization while controlling for respondents' lifestyles. The data for this study are drawn from a secondary dataset from a collaborative study by American and Saudi scholars. The data were collected in Jeddah, Saudi Arabia, which is a city of 3 million residents. The sample includes 500 males and 500 females in grades 10th through 12th, who were surveyed across eight different schools. The survey collected responses on a range of behaviors and experiences, from delinquent involvement to (open full item for complete abstract)

Committee: John Wright Ph.D. (Committee Chair); Francis Cullen Ph.D. (Committee Member); Cheryl Lero Jonson Ph.D. (Committee Member); Pamela Wilcox Ph.D. (Committee Member) Subjects: Criminology

Master of Science in Electrical Engineering (MSEE), Wright State University, 2017, Electrical Engineering

The thesis is aimed at developing optimal defensive strategies that dissuade an attacker from engaging a defender while simultaneously persuading the attacker to retreat. A two-player Engage or Retreat differential game is developed in which one player represents a mobile attacker and the other player represents a mobile defender. Both players are modeled as massless particles moving with constant velocity. The choice to terminate the game in engagement or retreat lies with the attacker. The defender indirectly influences the choice of the attacker by manipulating the latter's utility function. In other words, the defender co-operates with the attacker so that retreat appears to be the best option available. The solution to the differential game is obtained by solving two related optimization problems namely the Game Of Engagement and Optimal Constrained Retreat. In the Game of Engagement, the attacker terminates the game by capturing the defender.In the Optimal Constrained Retreat, a value function constraint is imposed which deters the attacker's retreat trajectory from entering into a region where it may lead to engagement. Such regions where constrained retreat occurs are known as escort regions. The solutions to these two problems are used to construct the global equilibrium solutions to the Engage or Retreat differential game.The global equilibrium solution divides the admissible state space into two regions that contain qualitatively different equilibrium control strategies. Numerical solutions are included to support the theory presented.

Committee: Zachariah E. Fuchs Ph.D. (Advisor); Luther Palmer Ph.D. (Committee Member); Xiadong (Frank) Zhang Ph.D. (Committee Member) Subjects: Electrical Engineering

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2016, Psychology/Developmental

The present study examined the relations between Theory of Mind and moral development as they impact specific aggressive behaviors and prosociality in preschoolers. Social-Cognitive and Social-Cognitive Domain Theory suggest that behavior should be considered a function of personal factors and environment, whereby each of these three facets impact and interact with one another, especially during the development of moral understanding. The current conceptualized hypothesized that moral judgment would predict socio-moral cognition, and – separately – that inhibitory control would predict Theory of Mind; additionally, a moderation of socio-moral cognition was posed on the expected relation from Theory of Mind to social outcomes. One hundred seventy-six preschoolers (Ma=53.3 months) completed measures of inhibitory control, moral understanding, morally imbedded Theory of Mind, verbal skills, and a traditional Theory of Mind battery consisting of five tasks. In addition, teacher- and child self-report data were collected for four specific aspects of aggressive behavior, and prosociality. The proposed model was a good fit to the data using teacher-report data. Results indicate that for children high in mental state understanding, applied moral cognitive development influences teacher-rated prosociality, such that those who were better able to understand another's motive tended to be less prosocial—for those without motive understanding, there was no relation from ToM on prosocial behavior. Implications are discussed in regards to theoretical development and previous empirical findings.

Committee: Marie Tisak (Advisor); John Tisak (Committee Member); Carolyn Tompsett (Committee Member); Susannah Cleveland (Other) Subjects: Cognitive Psychology; Developmental Psychology; Early Childhood Education; Psychology; Social Psychology

Doctor of Philosophy, Case Western Reserve University, 2015, EECS - System and Control Engineering

This thesis consists of various studies in information theory, including its connection with control theory and the computational aspects of information measures. The first part of the research investigates the connection between control theory and information theory. This part extends previous results that mainly focused on this connection in the context of state estimation and feedback control. For linear systems, mutual information, along with the concepts of controllability and observability, is used to derive a tight connection between control theory and information theory. For nonlinear systems, a weaker statement of this connection is established. Some explicit calculations for linear systems and interesting observations about these calculations are presented. The second part investigates the computation of mutual information. An innovative method to compute the mutual information between two collections of time series data based on a Hidden Markov Model (HMM) is proposed. For continuous-valued data, a HMM with Gaussian emission is used to estimate the underlying dynamics of the original data. Mutual information is computed based on the approximate dynamics provided by the HMM. This work improves the estimation of the upper and lower bounds of entropy for Gaussian mixtures, which is one of the key components in this proposed method. This improvement of these bounds are shown to be robust compared to existing methods in all of the synthetic data experiments conducted. In addition, this research includes the study of the computation of Shannon mutual information in which the strong assumptions of independence and identical distribution (i.i.d.) are imposed. This research shows that even if this assumption is violated, the results process a meaningful interpretation. The study of the computation of Shannon mutual information for continuous-valued random variables is included in this research. Three coupled chaotic systems are used as exemplars to show that the c (open full item for complete abstract)

Committee: Kenneth Loparo (Advisor); Vira Chankong (Committee Member); Marc Buchner (Committee Member); Richard Kolacinski (Committee Member) Subjects: Engineering; Mathematics

Doctor of Philosophy (PhD), Ohio University, 2015, Clinical Psychology (Arts and Sciences)

The current study assessed and integrated theories for Unwanted Pursuit Behaviors (UPBs), including real-life UPBs (e.g., following, showing up in places unexpectedly), and cyber UPBs (e.g., sending threatening text messages, monitoring a person's Facebook account). Theories tested included: attachment theory, the investment model theory, relational goal pursuit theory, and coercive control theory, and included variables such as self-control and emotion regulation difficulties which are postulated to underlie these theories. Whereas models predicting individual forms of cyber and real-life stalking showed different correlates of each form, results of an integrated model demonstrated that, whereas the coercive control model best predicts threatening forms of real-life and cyber UPBs, relational goal pursuit variables, and indirectly, investment model variables, best predict real-life and cyber unwanted contact/checking UPBs. Whereas the predictors varied by type (unwanted contact compared to threatening UPBs), the predictors for each modality of UPB (real-life or cyber) were similar. This pattern suggests that threatening UPBs are motivated by anger and desire for power/control, whereas unwanted contact/checking UPBs are motivated by desperate desires to maintain or reclaim loving relationships. Longitudinal research is needed to replicate the integrated model with consideration of temporal sequence; however, the current results emphasize the need for intervention in dating violence to prevent threatening UPBs when violent relationships are terminated. In addition, greater attention should be given to individuals who are the recipient of break-ups, because even if they do not engage in threatening post-break-up behaviors, those who engage in excessive and unwanted contact as a result of commitment and rumination about former partners are engaging in behaviors that are likely not in line with their desired goal (i.e., of reuniting with their former partners), and like (open full item for complete abstract)

Committee: Christine Gidycz PhD (Advisor); Julie Suhr PhD (Committee Member); Timothy Anderson PhD (Committee Member); Brian Wymbs PhD (Committee Member); Thomas Vander Ven PhD (Committee Member) Subjects: Clinical Psychology; Psychology

PhD, University of Cincinnati, 2011, Education, Criminal Justice, and Human Services: Criminal Justice

This dissertation tests the ability of four rival criminological theories to explain adolescent substance use: differential association/social learning theory, social bond theory, self-control theory, and general strain theory. Special attention is paid to whether the theories are general, as the inventors of the theories claim, or gender-specific to males, as critics of the theories claim. To undertake this theoretical assessment, a secondary analysis was conducted using data from the Rural Substance abuse and Violence Project (RSVP). The respondents, drawn from grades 7 to 12, were pooled across four waves. The N for this study is 9,488. The empirical test revealed three main conclusions. First, measures of the components of differential association/social learning theory, social bond theory, self-control theory, and general strain theory were able to explain substance use among adolescents. Second, the theories had general effects across males and females and thus were not gender-specific. Third, because all perspectives earned some empirical support, they might best be seen not as theoretical rivals but as complementary theories that all contribute to our understanding of the sources of substance use among youths. However, given the modest amount of variation explained in the analyses, future research on substance use may benefit from two extensions. First, most studies, including this dissertation, operationalize only parts of theories. The next generation of empirical tests should seek to measure all components of the major theories, thus truly assessing the models' explanatory potential. Second, a truly complete theory of substance use must build upon but not be limited to the major perspectives. Therefore, a need exists to examine the causal impact of factors—such as those unique to women or biological traits that shape conduct from childhood onward—that lie outside the traditional theories of crime.

Committee: Francis Cullen PhD (Committee Chair); Cheryl Lero Jonson PhD (Committee Member); Paula Smith PhD (Committee Member); Pamela Wilcox PhD (Committee Member) Subjects: Criminology

Master of Science, The Ohio State University, 2007, Electrical Engineering

Optimal foraging theory explains adaptation via natural selection through quantitative models. Behaviors that are most likely to be favored by natural selection can be predicted by maximizing functions representing Darwinian fitness. Optimization has natural applications in engineering, and so this approach can also be used to design behaviors of engineered agents. In this thesis, we generalize ideas from optimal foraging theory to allow for its easy application to engineering design. By extending standard models and suggesting new value functions of interest, we enhance the analytical efficacy of optimal foraging theory and suggest possible optimality reasons for previously unexplained behaviors observed in nature. Finally, we develop a procedure for maximizing a class of optimization functions relevant to our general model. As designing strategies to maximize returns in a stochastic environment is effectively an optimal portfolio problem, our methods are influenced by results from modern and post-modern portfolio theory. We suggest that optimal foraging theory could benefit by injecting updated concepts from these economic areas.

Committee: Kevin Passino (Advisor) Subjects:

Master of Arts (MA), Ohio University, 2007, Sociology (Arts and Sciences)

Work on the social construction of identity has emerged concurrently from different areas, each attempting to explain the plethora of identities present in society. Two such attempts, identity control theory and social identity theory, each attend to different portions of the social identity dynamic. Integration of these two approaches has the potential to increase understanding of interpersonal judgments. Traditionally, work utilizing social identity theory has been examined using a distribution of resources model. For this research evaluations of blame between subjects are examined in order to determine if in-group favoritism and out-group denigration as found in resource distribution studies are present in a post behavior evaluative framework.

Committee: Robert Shelly (Advisor) Subjects:

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2010, Psychology/Clinical

A well-established link between anxiety and impaired cognitive performance exists. Researchers have put forth several theories to explain the mechanisms of this relationship. Two such explanations are Cognitive Interference Theory (CIT) and Attentional Control Theory(ACT). The present study used a sample of 97 undergraduate students to test hypotheses made by both theories. Participants completed a demographic questionnaire and measures of state anxiety, evaluation anxiety, cognitive interference, and attentional control. They were randomly assigned to either an anxiety or a non-anxiety instruction condition and were then administered various cognitive tasks, which included measures of phonological loop, central executive, and visuospatial sketchpad functioning. The central executive tasks completed included measures of inhibition, switching, and updating. Results indicate that many CIT hypotheses were supported. Most notably, those receiving anxiety-inducing instructions experienced greater levels of evaluation anxiety and made more negative self-statements on a measure of cognitive interference. The anxiety condition was also associated with worse performance on measures of phonological loop and central executive, but not visuospatial sketchpad, functioning. Negative self-statements mediated the relationship between anxiety condition and performance on central executive tasks, accounting for approximately 23% of the variance in the relationship. Negative self-statements did not mediate the relationship between anxiety condition and phonological loop functioning, and accounted for very little of the variance in the relationship. Partial support was found for ACT. Specifically, measures of attentional control did not predict performance on central executive tasks. This held true for both measures of task effectiveness (errors made on the tasks) and task efficiency (time taken to complete tasks). The results were interpreted within both the CIT and ACT contexts. I (open full item for complete abstract)

Committee: William O'Brien Ph.D. (Advisor); Margaret Brooks Ph.D. (Committee Member); Robert Carels Ph.D. (Committee Member); Steve Jex Ph.D. (Committee Member) Subjects: Psychological Tests; Psychology

Master of Science, The Ohio State University, 1970, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1971, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2006, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1971, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1970, Graduate School

Committee: Not Provided (Other) Subjects: