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Title: African American athletes, actors, singers, peformers, and the anti-apartheid movement, 1948-1994
Creator: Jackson, Ronald L., 1970-
Date: 2018
Collection: Electronic Theses & Dissertations
Description: “African American Athletes, Actors, Singers, Performers and the Anti-Apartheid Movement, 1948-1994” is the first study to explore the multiple roles African American artists and athletes in the global struggle against apartheid in South Africa. As a transnational study, this dissertation pays attention to the multiple trans-Atlantic dialogues that occurred for over a century between African American entertainers and the people of South Africa. Based on archival sources in the United States...
Show more“African American Athletes, Actors, Singers, Performers and the Anti-Apartheid Movement, 1948-1994” is the first study to explore the multiple roles African American artists and athletes in the global struggle against apartheid in South Africa. As a transnational study, this dissertation pays attention to the multiple trans-Atlantic dialogues that occurred for over a century between African American entertainers and the people of South Africa. Based on archival sources in the United States and South Africa, it argues that many Black Americans in the popular culture industry used their celebrity status to galvanize support for a free South Africa, while others chose paths of accommodation, and, in some cases, collaborated with the Pretoria regime. African American singers, actors, musicians, boxers, golfers, and tennis players were often motivated, both intrinsically and extrinsically, by pan-African connections forged by an empathetic sense of a shared history of racial oppression endured by blacks in both the United States and South Africa during similar time periods. This study addresses questions about the African Diaspora that have not fully been addressed in previous studies. What factors prompted black American entertainers to join the anti-apartheid movement? Did anti-apartheid activists in South Africa consider the support of black American entertainers an essential component of the struggle? Why did some black American entertainers elect to ignore the cultural boycott and tour South Africa?
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Title: Africana women stories : mothering in African centered educational leadership
Creator: Caesar, Tiffany D.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "The current dissertation examines the stories of black women leaders in African Centered Education (ACE) in South Africa and Detroit using 'mothering' as a core theoretical framework to examine Black women's leadership globally. Pan-Africanism, African Centeredness, and womanism are theories within the study that provide a further understanding of their interwoven narratives. By focusing on the context, emergent themes, and aesthetic whole within a portraiture methodology -- the study hopes...
Show more"The current dissertation examines the stories of black women leaders in African Centered Education (ACE) in South Africa and Detroit using 'mothering' as a core theoretical framework to examine Black women's leadership globally. Pan-Africanism, African Centeredness, and womanism are theories within the study that provide a further understanding of their interwoven narratives. By focusing on the context, emergent themes, and aesthetic whole within a portraiture methodology -- the study hopes to shed light on what it refers to as 'Africana' women's stories. Distinctively, the dissertation study expands on the existing narrative of black women educators presenting them as leaders and using mothering as praxis by adding two originally researched elements - the experiences of black women leaders in African Centered Education and the current racialized and gendered transnational dialogue occurring between women in Detroit, Michigan and South Africa. 'Mothering' as praxis is mentioned throughout the experiences of black women educators (Baylor)(Gumbs)(Msila)(T. Karenga) (Hill-Brisbane) (Johnson L) (Johnson)(Collins). The concept essentially "involves valuing and of itself a commitment to the survival and thriving of other bodies" (Oka, 52). The role of the mother includes the ability to nurture, teach, mold, pass down culture, mentor, and support spiritual regeneration of our ancestors (T. Karenga) (Dove, 520) (Godono). With the current dissertation; these activities extended to 'emancipatory organizations, institutions, and social movements as is reflected in the history of the mothers of the freedom movements in this country and throughout the pan-African world' (Karenga)."--Pages ii-iii.
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Title: Agency in context : a phenomenological study of Chinese college lLearners' intercultural engagement with expatriate instructors
Creator: Larson, Jay B.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "As China increasingly internationalizes its higher education system, growing numbers of Chinese learners and expatriate instructors meet in the classroom, engaging one another from their disparate cultural and pedagogical standpoints. Despite its widespread occurrence, the phenomenon of Chinese learners and Western instructors engaging one another in pedagogically and culturally Chinese institutions is largely neglected in research. Scholarly literature on Chinese learners is dominated by...
Show more"As China increasingly internationalizes its higher education system, growing numbers of Chinese learners and expatriate instructors meet in the classroom, engaging one another from their disparate cultural and pedagogical standpoints. Despite its widespread occurrence, the phenomenon of Chinese learners and Western instructors engaging one another in pedagogically and culturally Chinese institutions is largely neglected in research. Scholarly literature on Chinese learners is dominated by studies of their experiences as international students on Western campuses. In Chinese environments, authors most often examine perspectives of expatriate instructors on their cultural adjustments. The voice of the Chinese learner in China is rarely heard in research. In this study, I turned a phenomenological lens toward 17 Chinese learners' lived experiences of intercultural classroom engagement at China's Southwest University. Drawing on works of Hall (1997a, 1997b), Said (1978), and Simmel (1971), I devised a Progression Model of Intercultural Engagement to frame participants' evolving perceptions of expatriate instructors as culturally foreign Others. I focused my analysis of learners' perceptions through three overlapping areas of inquiry: (a) learners' sense-making processes and management of intercultural teaching and learning; (b) their perceptions of the expatriate instructor as a physical, social, and cultural presence; and, (c) perceptions of expatriate instructor's course design and teaching. I collected data over a two-month period at Southwest University through methods including classroom observations, Chinese language participant essays, and English language interviews. Findings revealed learners exercised ownership and agency in interpreting and managing intercultural engagement with their instructors. Participants expressed ownership of a perceived physically, linguistically, and academically Chinese environment. Within that environment, they initially characterized expatriate instructor by foreign-ness. Learners made further sense of intercultural experience by situating their instructors' foreign-ness in constructed social, pedagogical, linguistic, and cultural roles. These roles assigned purpose to the expatriate instructor's foreign presence, and framed the meanings learners constructed from intercultural engagement. Finally, participants interpreted their relationships with written and spoken English through engagement with expatriate instructors perceived as social, pedagogical, and cultural embodiments of language. In sum, findings indicate perceived cultural context of the environment, and senses of ownership and agency learners exercised in this environment. These findings contribute to the academic dialogue on intercultural teaching and learning, not only in Chinese institutional contexts, but anywhere knowledge construction must bridge cultural assumptions, epistemologies, and pedagogies. This study can inform further inquiry into international learners on Western campuses, multinational classes in education hubs, and Western learners studying abroad. I address these applications, and others, as I conclude this dissertation with recommendations for practice, and implications for research and theory."--Pages ii-iii.
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Title: Alignment Control for Optical Communication between Underwater Robots
Creator: Solanki, Pratap Bhanu
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Light-emitting diode (LED)-based optical communication is emerging as a promising low-power, low-cost, and high-data-rate alternative to acoustic communication for underwater applications. However, it requires a close-to-line-of-sight (LOS) link between the communicating parties.Achieving and maintaining the LOS is challenging due to the constant movement of underlying mobile platforms caused by propulsion and unwanted disturbances. In this dissertation, a novel, compact LED-based wireless...
Show moreLight-emitting diode (LED)-based optical communication is emerging as a promising low-power, low-cost, and high-data-rate alternative to acoustic communication for underwater applications. However, it requires a close-to-line-of-sight (LOS) link between the communicating parties.Achieving and maintaining the LOS is challenging due to the constant movement of underlying mobile platforms caused by propulsion and unwanted disturbances. In this dissertation, a novel, compact LED-based wireless communication system with active alignment control is presented that maintains the LOS despite the movement of the underlying platform. Multiple alignment control algorithms are developed for scenarios that range from a simple one-way two-dimensional (2D) setting to a practical three-dimensional (3D) bi-directional underwater setting. An extended Kalman filter (EKF)-based approach is first proposed to estimate the relative orientation between the heading angle and the LOS direction, which is subsequently used for alignment control. The EKF uses only the measurement of light intensity from a single photo-diode, where successive measurements are obtained via a scanning technique that ensures the full observability of the underlying system. The approach is first examined in a 2D setting, and then extended to the 3D scenario with improvements in both the hardware and the algorithm. The amplitude of the scanning is modulated according to the alignment performance to achieve a sound trade-off between estimation accuracy, signal strength, and energy consumption. The efficacy of the approach is tested and verified via simulation and on an experimental setup involving two robots with relative 3D motion. The EKF approach uses an assumption that the relative motion between the robots is small, and consequently, requires the communicating robots to take the scanning in an alternating fashion for the convergence of the estimator. An alternative approach, first explored in the 2D setting, is developed that allows simultaneous, bi-directional alignment control for both parties. Because of the convex nature of the measured intensity functions, model-free approaches, including both hill-climbing (HC) and extremum-seeking (ES), are explored. The hill-climbing approach is found to be superior to the ES approach in terms of convergence time and computational efficiency. Theoretical analysis is provided for the hill-climbing approach that guarantees finite time convergence to an $O(\delta)$ neighborhood of the LOS, for control step size $\delta$.Finally, a model-free approach for the 3D setting is proposed that maximizes light intensity based on three consecutive intensity measurements from an equilateral triangle configuration. The efficacy of the approach is demonstrated experimentally, first with an underwater robot controlled by a joystick via LED communication and then with two robots performing bi-directional communication and tracking in an underwater setting.
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Title: Alignment between intensity of risk and level of collaboration in partnered architecture, engineering and construction projects : a quantitative approach to test impacts on project performance outcomes
Creator: Kalbhor, Harshavardhan Vijay
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Risk is a typical characteristic of Architecture, Engineering, and Construction (AEC) projects due to their inherent complexities. The intensity of such risk is influenced by factors such as the dynamic nature of project elements (e.g., fragmented multi-disciplinary project teams), interactions among these elements, and lack of clear project goals. Project management theory and practice both endorse that as the intensity of risk in a project increases, a higher level of collaboration among...
Show moreRisk is a typical characteristic of Architecture, Engineering, and Construction (AEC) projects due to their inherent complexities. The intensity of such risk is influenced by factors such as the dynamic nature of project elements (e.g., fragmented multi-disciplinary project teams), interactions among these elements, and lack of clear project goals. Project management theory and practice both endorse that as the intensity of risk in a project increases, a higher level of collaboration among the multi-disciplinary project teams is desirable in order to achieve optimal project performance outcomes.To facilitate higher or improved level of collaboration among project teams, the AEC industry utilizes innovative project delivery methods (e.g., IPD), technologies (e.g., BIM), and practices (e.g., Lean Construction). Project Partnering is one such project delivery practice; adopting which, two or more organizations commit to harboring an environment of collaboration (e.g., effective communication, shared vision, goal alignment, trust) in a structured approach, with the intention of achieving optimum shared project performance goals (e.g., reduced costs, delays).Although both researchers and practitioners commonly recognize that collaboration is an effective risk management strategy, a theoretical gap exists in providing empirical reinforcement supporting this assertion. A part of this gap is due to the lack of a structured framework for investigating collaboration. Partnering fulfills this shortcoming and provides a structured framework to study collaboration analytically. Thus, partnered AEC projects are the focus and unit of analysis for this research.In addition, existing Partnering literature is largely qualitative and presents conceptual models, potential benefits to adopting Partnering, barriers to its adoption, critical success factors, and performance measurement and evaluation methods. Quantitative research in this domain is limited and has studied projects either coming largely from a single source of ownership (e.g., DOTs) or a particular project type (e.g., horizontal infrastructure projects) at a time. There is a need for evidence-based quantitative research that identifies specific factors linked to partnered-project success using data from a large and diversified sample of projects.Thus, the need for an empirical assessment of the association (denoted by the variable fit) between risk (specifically its intensity) and level of collaboration (via partnering practices in this study), and its impact on project performance prompted the undertaking of this study. Due to lack of pre-defined terminology to capture the association between risk intensity and partnering level, it was denoted in this study via an introduction of the variable 'fit'. The goal of the study is to investigate partnered AEC projects for the impact of the fit between their intensity of risk and adopted partnering level on their performance outcomes (e.g., cost, schedule). Accordingly, this study aims to answer the following research question: 'In partnered AEC projects, does the fit between risk intensity and level of partnering correlate with performance outcomes?' The hypothesis developed by the researcher is that 'In a partnered project, better the fit between the intensity of risk and adopted partnering level, better is its performance.' This study used an archival data-set containing details of 127 partnered projects from the United States completed between 2010 and 2018. Literature study followed by an exploratory data analysis was conducted to develop models to determine constructs of interest - risk intensity, partnering level and performance evaluation metrics, from AEC project characteristics. The models were validated via a survey; and are one of the outcomes of this study. Further, via content analysis, quantitative measures of these constructs were systematically coded from project details in the data set.The hypothesis of this study was tested separately for different performance outcome metrics (e.g., cost growth, schedule growth) via a quantitative approach of unsupervised statistical learning tests such as the Kruskal-Wallis test and the Dunn Test for comparison of performance metric data as samples across the fit categories. The deliverable of this study are tools or models for risk intensity assessment and simultaneous determination of recommended level of partnering. The study was able to contribute to the body of knowledge of risk management via collaboration by providing empirical reinforcement to the association or lack of thereof between risk, collaboration and performance. Lastly, this study provides guidelines for best practices in Partnering contributing to effective risk management on AEC projects.
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Title: Allied studies on total sythesis of cyclic tripeptide TMC-95 via an iridium catalyzed borylation/deborylation strategy and teaching organic chemistry in "words"
Creator: Shen, Fangyi
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Arylboronate esters are versatile synthetic building blocks. Iridium catalyzed C-H activation/borylation reactions are a green way of making such building blocks as these reactions often obviate the need for prior functionalization (e.g. halogenation), the use of pyrophoric reagents, cryogenic conditions, etc. Installation of multiple boron substituents about the starting arene and then Ir catalyzed selective deborylation of the individual borons can allow for the formation of an even greater...
Show moreArylboronate esters are versatile synthetic building blocks. Iridium catalyzed C-H activation/borylation reactions are a green way of making such building blocks as these reactions often obviate the need for prior functionalization (e.g. halogenation), the use of pyrophoric reagents, cryogenic conditions, etc. Installation of multiple boron substituents about the starting arene and then Ir catalyzed selective deborylation of the individual borons can allow for the formation of an even greater diversity of borylated building blocks.The regioselectivity of Ir-catalyzed borylation is usually driven by sterics, however heterocycles are known to borylated at positions that exhibit heightened C-H acidity through the influence of the heteroatom. The regioselective borylation attained with a tryptophan derivative has been utilized in the development of a novel convergent route to the TMC-95 core. While pursuing a model synthesis of this natural product, the ability of bismuth salts to catalyze deborylations was discovered. These bismuth salts mediated methods can be highly selective in the in the deborylation of di and triborylated indoles. Furthermore, bismuths compounds are safe and less expensive as compared to the Ir-catalysts that facilitated deborylation. Numerous screening experiments on both substrates and other metal salts afforded a better understanding of how these novel deborylations can be applied in various synthetic settings and provided insight into possible mechanisms.Also, while I was a teaching assistant and a fixed-term instructor during my graduate studies at Michigan State University, I gradually realized that teaching is my passion and I am prepared to start my independent career and be an independent thinking teacher for the organic chemistry area.Owing to the nature of the subject, organic chemistry can be very visually distracting, and the image can be overpowering during student's learning. Like it or not students will try memorization first, our hypothesis is that once they know the "organic transformation formula" in words, via memorization or any other method, then introducing them to the structures of these functional groups will come with added context, and once they make that jump from word to structure they will be in a better position to understand reaction mechanisms. More importantly, understanding those reaction mechanisms will enable the student to progress to more complex topics.By introducing functional group transformations without the "clutter" of structures, we predict that once structures are introduced students will prioritize what's important because they will have trained their minds to ask what is the functional group, not "where did I see that structure in my notes".In short, we aim to train students to focus their attention on the reactive functional group of an organic molecule by emphasizing the use of WORDS to describe functional group transformation and teach the organic chemistry as the second language.
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Title: Amandla : the time has come for us to plan action that will put a stop to detention
Creator: MEDU Art Ensemble (Gaborone, Botswana)
Date: 1981
Collection: Africana Posters Collection
Description: Silkscreen poster shows text "Amandla" in the center with a line underneath text. Both are white. Four thick red links in a box are in the upper right corner. Background is gray and white. Subtitle text in red and on the bottom.

Title: American mass shooters and suicide
Creator: Brown, Kylei Elizabeth
Date: 2018
Collection: Electronic Theses & Dissertations
Description: Mass shootings are traumatic events associated with highly publicized and often gruesome homicides that raise public alarm. Yet, researchers know relatively little about shooters and mass shooting events. Therefore, it is important to further extend the research of mass shootings to characterize different types of shooters and how they ultimately perpetrate their attacks. As such, the current study investigated the differences between American mass shooters who commit suicide after their...
Show moreMass shootings are traumatic events associated with highly publicized and often gruesome homicides that raise public alarm. Yet, researchers know relatively little about shooters and mass shooting events. Therefore, it is important to further extend the research of mass shootings to characterize different types of shooters and how they ultimately perpetrate their attacks. As such, the current study investigated the differences between American mass shooters who commit suicide after their attacks and mass shooters who do not. This study examined shooter vitality in 185 mass shootings in America perpetrated by 194 mass shooters between 2000 and 2016. Each shooter was categorized as having survived the attack or the manner in which they died; whether by self-inflicted suicide or being shot by another person. This revised data about how the mass shooters died was compared with thirty-three different independent variables that looked at the characteristics of the mass shooters as well as the characteristics of the mass shootings using both analysis of variance and binary logistic regression analytic techniques. At the same time, an original version of this dataset was tested alongside the revised dataset to look for similarities and comparisons in the results. The results of the revised dataset showed that mass shooters with a prior criminal record are more likely to survive their attacks and those who kill more victims are less likely to survive their attacks. These results are useful to inform both law enforcement personnel intervening in a mass shooting as well as lawmakers developing policies in an attempt to decrease the number of mass shootings in America.
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Title: An Experimental Study of the Steadily Plunging Airfoil in Uniform-Shear Flow
Creator: Albrecht, Mitchell Baxter
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Freestream shear may be found in many unsteady aerodynamic situations, such as the fighter jet landing through the air wake of an aircraft carrier and the micro air vehicle (MAV) navigating wind currents around buildings in urban environments. Despite the prevalence of shear in aeronautics, literature concerning its effects on unsteady airfoils is scarce. To address the need to understand the fundamental, complex aerodynamics of moving airfoils coupled with freestream shear, a novel...
Show moreFreestream shear may be found in many unsteady aerodynamic situations, such as the fighter jet landing through the air wake of an aircraft carrier and the micro air vehicle (MAV) navigating wind currents around buildings in urban environments. Despite the prevalence of shear in aeronautics, literature concerning its effects on unsteady airfoils is scarce. To address the need to understand the fundamental, complex aerodynamics of moving airfoils coupled with freestream shear, a novel experimental setup was implemented to investigate the case of the airfoil steadily plunging across a canonical uniform-shear approach flow in a water tunnel. The effect of unsteadiness on the NACA 0012 airfoil in shear is examined by using a servo motion system to plunge the airfoil from the high- to low-speed extremes of the shear zone and varying the steady plunge speed. The aerodynamic load (lift and drag coefficients), streamwise velocity component of the flow, separation and reattachment locations, and boundary layer thickness are characterized such that the flow measurements are correlated to the observed behavior of the load measurements. First, uniform flow measurements are performed that confirm the unique experimental setup reproduces the expected Galilean transformation between the stationary and steadily plunging airfoils. It is confirmed that minimal blockage, confinement, or other artifacts result from the airfoil traversing over a large fraction of the test section's width. Molecular tagging velocimetry is uniquely implemented such that tag lines are created over the entire airfoil surface, image pairs are formed with the entire airfoil in view, and flow measurements are enabled for the moving airfoil. The airfoil aerodynamics are characterized in uniform flow at the same Reynolds numbers of the shear flow at three primary cross-stream locations of interest to provide baselines for the measurements in shear. For Reynolds numbers 13,500 and 16,500, a multi-region behavior is observed in the slope of the lift coefficient curve where the observed rapid rise in lift is related to the flow switching from an open separation to a closed separation bubble. By contrast, a steady rise in lift is observed at Reynolds number 9,800 which correlates to only open separation being observed.Next, the basic effect of shear on the stationary airfoil is studied by placing the airfoil at the three primary cross-stream locations in the shear flow, which also provides baseline measurements for the plunging airfoil in shear. It is observed that the current study reproduces the negative lift at zero angle of attack that is opposite of inviscid theory but consistent with recent computational and experimental literature from our group. A common observation in the lift and drag coefficient curves for the stationary airfoil in shear is asymmetry, as exemplified by the different stall behavior between positive and negative angles of attack. A multi-region behavior is observed among the lift curves which is connected to the airfoil switching from open separation to a closed separation bubble, like for uniform flow. Except for the Reynolds number 13,500 case, there is no observed difference in the angle of attack at which the flow switches from open separation to a closed separation bubble in shear compared to uniform flow. For the highest shear, lowest Reynolds number case, only open separation is observed at positive angles of attack, like the corresponding results in uniform flow.Finally, the effect of the steadily plunging airfoil motion in shear is studied in comparison with its stationary airfoil counterpart. For the range of dimensionless shear rates (0.40-0.69) and chord Reynolds numbers (9,800-16,500) in this study, it is observed that the slope of the lift coefficient curve for the plunging airfoil begins to rapidly increase at lower effective angle of attack than for the stationary airfoil, which is found to be a result of the flow reattaching at a lower effective angle of attack for the former than for the latter. Near stall, the magnitude of the lift coefficient on the plunging airfoil is typically greater than that on the stationary airfoil, which is found to be related to the reattachment point occurring farther upstream for the former than for the latter. It is found that the airfoil must plunge as slowly as 1% of the freestream speed for the load on the plunging airfoil to be well-approximated by that on the stationary airfoil for the same effective angle of attack and freestream conditions.
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Title: An accurate, efficient, and robust fingerprint presentation attack detector
Creator: Chugh, Tarang
Date: 2020
Collection: Electronic Theses & Dissertations
Description: The individuality and persistence of fingerprints is being leveraged for a plethora of day-to-day automated person recognition applications, ranging from social benefits disbursements and unlocking smartphones to law enforcement and border security. While the primary purpose of a fingerprint recognition system is to ensure reliable and accurate user recognition, the security of the system itself can be jeopardized by the use of fingerprint presentation attacks (PAs). A fingerprint PA is...
Show moreThe individuality and persistence of fingerprints is being leveraged for a plethora of day-to-day automated person recognition applications, ranging from social benefits disbursements and unlocking smartphones to law enforcement and border security. While the primary purpose of a fingerprint recognition system is to ensure reliable and accurate user recognition, the security of the system itself can be jeopardized by the use of fingerprint presentation attacks (PAs). A fingerprint PA is defined as a presentation, of a spoof (fake), altered, or cadaver finger, to the data capture system (fingerprint reader) intended to interfere with the recording of the true fingerprint sample/identity, and thereby preventing correct user recognition.In this thesis, we present an automated, accurate, and reliable software-only fingerprint presentation attack detector (PAD), called Fingerprint Spoof Buster. Specifically, we propose a deep convolutional neural network (CNN) based approach utilizing local patches centered and aligned using fingerprint minutiae. The proposed PAD achieves state-of-the-art performance on publicly available liveness detection databases (LivDet) and large-scale government controlled tests as part of the IARPA ODIN program. Additionally, we present a graphical user interface that highlights local regions of the fingerprint image as bonafide or PA for visual examination. This offers significant advantage over existing PAD solutions that rely on a single spoof score for the entire fingerprint image.Deep learning-based solutions are infamously resource intensive (both memory and processing) and require special hardware such as graphical processing units (GPUs). With the goal of real-time inference in low-resource environments, such as smartphones and embedded devices, we propose a series of optimizations including simplifying the network architecture and quantizing model weights (for byte computations instead of floating point arithmetic). These optimizations enabled us to develop a light-weight version of the PAD, called Fingerprint Spoof Buster Lite, as an Android application, which can execute on a commodity smartphone (Samsung Galaxy S8) with a minimal drop in PAD performance (from TDR = 95.7% to 95.3% FDR = 0.2%) in under 100ms.Typically, deep learning-based solutions are considered as "black-box" systems due to the lack of interpretability of their decisions. One of the major limitations of the existing PAD solutions is their poor generalization against PA materials not seen during training. While it is observed that some materials are easier to detect (e.g. EcoFlex) compared to others (e.g. Silgum) when left out from training, the underlying reasons are unknown. We present a framework to understand and interpret the generalization (cross-material) performance of the proposed PAD by investigating the material properties and visualizing the bonafide and PA samples in the multidimensional feature space learned by deep networks. Furthermore, we present two different approaches to improve the generalization performance: (i) a style transfer-based wrapper, called Universal Material Generator (UMG), and (ii) a dynamic approach utilizing temporal analysis of a sequence of fingerprint image frames. The two proposed approaches are shown to significantly improve the generalization performance evaluated on large databases of bonafide and PA samples.Lastly, fingerprint readers based on conventional imaging technologies, such as optical, capacitive, and thermal, only image the 2D surface fingerprint making them an easy target for presentation attacks. In contrast, Optical Coherent Tomography (OCT) imaging technology provides rich depth information, including the internal fingerprint, eccrine (sweat) glands, as well as PA instruments (spoofs) placed over finger skin. As a final contribution, we present an automated PAD approach utilizing cross-sectional OCT depth profile scans which is shown to achieve a TDR of 99.73% FDR of 0.2% on a database of 3,413 bonafide and 357 PA OCT scans, fabricated using 8 different PA materials. We also identify the crucial regions in the OCT scans necessary for PA detection.
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Title: An agent model of vertical integration in telecommunications and content
Creator: Koning, Kendall Jay
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "This dissertation explores several important telecommunications policy issues in light of recent developments in the wireline broadband and online video markets." -- Abstract.

Title: An analysis of content knowledge and cognitive abilities as factors that are associated with algebra performance
Creator: McLean, Tamika Ann
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "The current study investigated college students' content knowledge and cognitive abilities as factors associated with their algebra performance, and examined how combinations of content knowledge and cognitive abilities related to their algebra performance. Specifically, the investigation examined the content knowledge factors of computational fluency, numeracy skills, fraction knowledge, understanding of equivalence, and algebraic reasoning skills, and the cognitive abilities of spatial...
Show more"The current study investigated college students' content knowledge and cognitive abilities as factors associated with their algebra performance, and examined how combinations of content knowledge and cognitive abilities related to their algebra performance. Specifically, the investigation examined the content knowledge factors of computational fluency, numeracy skills, fraction knowledge, understanding of equivalence, and algebraic reasoning skills, and the cognitive abilities of spatial visualization, crystallized intelligence, and fluid intelligence. A multiple regression analysis found that while controlling for gender, the highest math course taken, and the number of years since an algebra course, fraction knowledge and the spatial visualization ability of spatial imagery were statistically significant predictors of algebra performance along with the control variable identifying whether or not participants had taken at least one calculus course. In addition, cluster analysis identified six content knowledge and cognitive ability profiles, with varying levels of both content knowledge and cognitive abilities observed across the six clusters. The six profiles - characterized as Low All, Moderate-Low All, Moderate-High MASMI, Moderate-Low Spatial, Moderate-High All, and High Spatial - varied somewhat in terms of their algebra performance scores. In particular, the participants in the High Spatial cluster group and participants in the Moderate-High All cluster group had similarly high algebra performance scores, which were significantly higher than performances scores observed for participants in the other cluster groups. Additionally, the participants in the other cluster groups exhibited similar low algebra performance scores to each other except for participants in the in the Moderate-Low Spatial and Low All cluster groups. Participants in the Moderate-Low Spatial cluster group had significantly higher algebra performance scores than participants in the Low All cluster group. The differences in algebra performance scores among cluster groups suggested that the observation of higher algebra performance occurred when participants had strong spatial visualization skills, strong fluid intelligence skills, and high content knowledge or when participants had strong fraction knowledge, numeracy skills, algebraic reasoning skills, and spatial imagery skills."--Pages ii-iii.
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Title: An assessment of protective factors in predicting juvenile reoffending
Creator: Barnes, Ashlee R.
Date: 2017
Collection: Electronic Theses & Dissertations
Description: Juvenile court practitioners use risk assessment to evaluate level of risk and criminogenic areas of need to determine the most appropriate consequence for young offenders, and to determine goals for case planning. Recently, juvenile court practitioners and researchers have gained interest in evaluating young offenders' internal and external strengths, or protective factors. Some scholars assert that incorporating measures of protective factors into the risk assessment process can increase...
Show moreJuvenile court practitioners use risk assessment to evaluate level of risk and criminogenic areas of need to determine the most appropriate consequence for young offenders, and to determine goals for case planning. Recently, juvenile court practitioners and researchers have gained interest in evaluating young offenders' internal and external strengths, or protective factors. Some scholars assert that incorporating measures of protective factors into the risk assessment process can increase the accuracy of identifying young offenders' odds of recidivating. Relatively few juvenile risk assessment validation studies have evaluated the predictive validity of protective factor items. Moreover, protective factor items that are included in many existing risk assessment tools are narrow in scope, particularly within family-, school-, and community-level protective factor domains. The current study examined the relationship between protective factors and recidivism for 278 young probationers from a Midwestern juvenile county court. The study was conducted in two parts. First, a strengths-based measure of risk of recidivism (Protective Factors for Reducing Juvenile Reoffending, PFRJR) was created and its factor structure and reliability was evaluated. Second, the predictive validity, incremental validity, and differential predictive validity of the PFRJR were examined. In the first study, the author identified two factors, Individual/Community and Family/Social; both subscales demonstrated strong internal consistency. In the second study, the author found no significant differences in mean level composite protective factor scores across gender, however African American offenders had significantly lower protective factor scores than White offenders. The PFRJR significantly predicted recidivism and time-to-recidivism, and produced AUC effect sizes that ranged from small to large for the total sample and across young offender subgroups. The author did not find evidence of differential predictive validity across gender, however the author found differential predictive validity by race/ethnicity. Regarding the incremental validity of protective factor scores, the PFRJR composite scores did not increase the amount of variance explained in recidivism after accounting for the variance explained by composite risk factor scores (as measured by the Youth Level of Service/Case Management Inventory). Broadly, the current study highlights the feasibility of integrating a complementary strengths-based measure into traditional risk assessment procedures. Findings from the current study also contributed to the paucity of risk assessment validation studies that emphasized the predictive validity of protective factor scores.
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Title: An ecological exploration of sport specialization pathways
Creator: DiSanti, Justin S.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: Youth sport specialization has been a sustained area of interest in academic and practical settings. Though preliminary findings of the relationship between athletes' pathways of sport participation and their sport outcomes posit early specialization in a single sport as potentially harmful to an athlete's physical and psychological well-being, concern that athletes are specializing earlier, and to a greater degree, than ever before remains pervasive. In analyzing potential explanations for...
Show moreYouth sport specialization has been a sustained area of interest in academic and practical settings. Though preliminary findings of the relationship between athletes' pathways of sport participation and their sport outcomes posit early specialization in a single sport as potentially harmful to an athlete's physical and psychological well-being, concern that athletes are specializing earlier, and to a greater degree, than ever before remains pervasive. In analyzing potential explanations for this logical gap between recommendations and perceived behaviors, one notable gap of the literature is the lack of ecological, systems-based research that may better clarify what drives athletes to specialize in a single sport. In this study, a developmental, ecological, perception-based approach was used to explore youth athletes' pathways of sport participation (specifically, why they chose to specialize or play multiple sports) in relation to their ecological characteristics and subsequent sport experiences. To do so, a conceptual, ecological framework was developed to inform the design of this study, and the nature and strength of relationships between variables of this novel heuristic provided an initial understanding of the ecology of sport participation pathways. 132 current high school athletes participated in this study's testing battery, which surveyed elements of their sport participation, personal and contextual characteristics, their sport specialization behaviors and perceptions, and their expectations and subsequent experiences related to their chosen pathway. Results of this study highlighted several significant group differences and relationships between variables, and due to the exploratory nature of this study the non-significant findings also served as a hypothesis-generating mechanism for future research. Implications of these findings were explored in their relation to previous sport specialization literature and the study's guiding theoretical framework (i.e., the Developmental Model of Sport Participation and the Person-Process-Context-Time Ecological Model), and the results underscored the importance of accounting for the influence of context and competitive climate in understanding youth athletes' selected sport pathways and subsequent experiences.
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Title: An experimental parametric study on the efficiency of hybrid fastening system
Creator: Ramli, Salina
Date: 2020
Collection: Electronic Theses & Dissertations
Description: As the use of fiber-reinforced polymer composites in mass-produced structural components in all domains of industry has grown, appropriate advancements in joining systems are necessary. Bolted joints are a common method used due to the simplicity of the process. Drilling holes in composites for fastening results in delamination, creation of locations for the onset of failure, and can reduce load-carrying capacities. Hybrid fastening techniques and other approaches for joining composite...
Show moreAs the use of fiber-reinforced polymer composites in mass-produced structural components in all domains of industry has grown, appropriate advancements in joining systems are necessary. Bolted joints are a common method used due to the simplicity of the process. Drilling holes in composites for fastening results in delamination, creation of locations for the onset of failure, and can reduce load-carrying capacities. Hybrid fastening techniques and other approaches for joining composite materials have been developed as a way to address problems related to conventional bolted joints. One such technique is the hybrid fastening system in which a structural adhesive insert is placed in the bolt-hole clearance. This approach has been shown to eliminate bolt-adherend slip, reduce delamination, and increase load-bearing capacities. Nevertheless, the extant work on such a hybrid fastening system is limited. In this work, experimental characterizations of hybrid fastening systems comprised of glass fiber reinforced polymer (GFRP) composite substrates fastened using a fully threaded grade 5 steel bolts in 1/2" (12.5 mm.) diameter with varying bolt hole clearance and three structural insert materials were performed. The GFRP substrates were manufactured using the vacuum-assisted resin transfer molding (VARTM) process. The preload was maintained at 75% of the bolt yield strength for all joints. The objective of this work was to characterize/quantify the effect of: a) the adhesive insert and b) the bolt-hole clearances on the efficiency of the hybrid fastening system. For the first parameter, namely the effect of the adhesive insert, four configurations, namely the hybrid fastening system with three different structural insert materials and one control/conventional joint without any structural insert were studied. Adhesive insert materials used were PRO-SET epoxy resin, DEVCON epoxy carrying aluminum particles, and polyurethane. All resulting joints were cured at room temperature for 48h prior to testing. For the second parameter, namely the effect of bolt clearance, four different bolt-hole clearances: close fit (0.5mm), normal fit (1.0 mm.), loose fit (1.5 mm.), and extra loose fit (2.0 mm.) were studied for each of the insert materials along with the control/conventional joint without any structural insert. The resulting joints were tested in a tensile-shear configuration at a rate of 5 mm./min. Hybrid joints were found to have 7 to 9 times higher load carrying capacities relative to slip-loads for conventional joints. All hybrid fastening systems showed no bolt-adherend slip along with delayed onset of delamination relative to conventional joints. Most of the joints with close fit (0.5mm) clearance were found to experience a catastrophic failure which resulted in bolt shearing failure. All other joints experienced progressive delamination failure without any bolt-shear failures. Further, the results indicate that the failure mechanism changed with the changes of bolt-hole clearances. The larger the clearances, the more the bolt tilts/rotates and experiences a combination of bending and shear. For small clearances, such as close-fit, shear dominates and bolt-shear occurs leading to bolt fracture. The combination of slightly larger clearance along with a structural adhesive insert allows tailoring the bolt- joint performance, leading to 7-9 times better performance than conventional joints with similar clearances. Future work should focus on quantifying the stress-concentrations and its reductions due to the addition of structural inserts. Overall, this work is novel and the first to report on the effect on clearance and varying adhesive insert materials for hybrid mechanical joints.
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Title: An exploration of mid- to high-valent transition metal complexes for application to catalysis
Creator: Aldrich, Kelly E.
Date: 2019
Collection: Electronic Theses & Dissertations
Description: "The valency or oxidation state of a transition metal in a complex plays a large role in determining the reactivity of the complex. With transition metal chemistry, historically accessible chemistry has often focused on metals in a low oxidation state. However, transformations involving transition metals in high oxidation states are of equal importance in providing complex products for use in consumer products. Expanding the applications and understanding of transition metal complexes in high...
Show more"The valency or oxidation state of a transition metal in a complex plays a large role in determining the reactivity of the complex. With transition metal chemistry, historically accessible chemistry has often focused on metals in a low oxidation state. However, transformations involving transition metals in high oxidation states are of equal importance in providing complex products for use in consumer products. Expanding the applications and understanding of transition metal complexes in high oxidation states is the focus of the research presented in this dissertation. Fundamental studies of how ligands interact with high valent metals is presented in chapters 2 and 3, where a chromium(VI) model complex has been used to study bonding interactions between this d0 transition metal and phosphine ligands. Practical application of high valent titanium(IV) catalysts to C--N bond forming reactions is presented in chapters 4--6. Finally, chapters 7 and 8 focus on the changes in the character of M--N double bonds, with M=Fe and Ru, as the metal is forced to higher oxidation states. Collectively, these studies demonstrate different approaches to the same general problems and questions of how chemists can better understand and utilize high valent transitions metals to do catalytically-target desired transformations."--Page ii.
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Title: An individual differences approach to improving low target prevalence visual search performance
Creator: Peltier, Chad
Date: 2017
Collection: Electronic Theses & Dissertations
Description: "Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets that may only be present on as few as .3% of searches (Gur et al., 2004). When targets are rare, observers search for a shorter amount of time and miss targets more often than when targets are common, a phenomenon known as the low prevalence effect (LPE). Given the real-world importance of the detection of low prevalence targets, researchers have attempted to improve search...
Show more"Critical real-world visual search tasks such as radiology and baggage screening rely on the detection of rare targets that may only be present on as few as .3% of searches (Gur et al., 2004). When targets are rare, observers search for a shorter amount of time and miss targets more often than when targets are common, a phenomenon known as the low prevalence effect (LPE). Given the real-world importance of the detection of low prevalence targets, researchers have attempted to improve search performance. There have been several experimental attempts to reduce the LPE, but none have been wholly successful, as even the best methods have increased hits at the cost of more false alarms. As an alternative to improving visual search performance through experimental manipulations, researchers have recently started using an individual differences approach to predict those who would be best at rare target detection. The individual differences approach has shown that it is possible to predict low prevalence target detection using working memory capacity (WMC) (Peltier & Becker, 2016b; Schwark et al., 2012) and moderate prevalence target detection using a personality assessment (Biggs, Clark, & Mitroff, 2017) and vigilance (Adamo, Cain, & Mitroff, 2016). Experiment 1 expands on the previous research by predicting low prevalence visual search performance using measures of WMC, near transfer high prevalence visual search accuracy, vigilance, attentional control, and introversion. The regression using these predictors accounts for 52% of the variance in accuracy. Experiment 2 addresses practical and theoretical limitations of Experiment 1 by replicating the original finding, including new potential predictors of low prevalence search performance (fluid intelligence, task unrelated thought frequency, and far transfer search accuracy), using more realistic search stimuli to increase external validity, and using eye tracking to investigate how individual differences relate to specific components of performance. The results show that near transfer search, far transfer search, WMC, introversion, and fluid intelligence account for 53% of the variance in accuracy in a more realistic low prevalence search. Using the beta weights from Experiment 1's significant predictors and each observer's score on the corresponding measures in Experiment 2, I find that the old predictors account for 42% of the variance in a novel search task's accuracy. Finally, the eye-tracking results show that we can significantly predict quitting thresholds (the number of items inspected before terminating search), selection error rates (misses caused by never inspecting the target), identification error rates (misses caused by misidentifying an inspected target), item re-inspection rates, target decision times, and distractor decision times. I conclude that the individual differences approach has the potential to be a highly effective tool in selecting those who are most likely to perform at a high level in real-world searches."--Pages ii-iii.
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Title: An interactive knowledge-driven multi-objective optimization framework for achieving faster convergence
Creator: Ghosh, Abhiroop
Date: 2022
Collection: Electronic Theses & Dissertations
Description: Users interested in solving real-world optimization problems often have many years of experience. Their intuition or 'knowledge' is often overlooked in academic studies due to concerns regarding loss of generality. Such knowledge can be expressed as inter-variable relationships or functions, which can provide some initial guidance to a suitably-designed optimization algorithm. Alternatively, knowledge about variable interactions can also be extracted algorithmically during the optimization by...
Show moreUsers interested in solving real-world optimization problems often have many years of experience. Their intuition or 'knowledge' is often overlooked in academic studies due to concerns regarding loss of generality. Such knowledge can be expressed as inter-variable relationships or functions, which can provide some initial guidance to a suitably-designed optimization algorithm. Alternatively, knowledge about variable interactions can also be extracted algorithmically during the optimization by analyzing the better solutions progressively found over iterations - a process termed innovization. Any common pattern extracted from good solutions discovered during an optimization run can be used as a repair operator to modify candidate solutions, but the key aspect is to strike a balance between the relevance of the pattern identified and the extent of its use in the repair operator, lest the learned patterns turn out to be properties of unpromising search directions or 'blind alleys'. In this dissertation, we propose a framework combining both user-supplied and algorithmically-extracted knowledge to repair solutions during an optimization run in an online fashion. Such a framework is also interactive, allowing the user to provide inputs at any point during the optimization. We show the step-wise modifications required for an evolutionary multi-objective (EMO) framework to allow for: (a) initial user-provided knowledge, (b) automated knowledge extraction and application using innovization methods, and (c) allowing the user to interact with the framework at any point during the optimization run. The path to creating such a framework is systematically performed one step at a time, starting from creating an efficient method of representing problem knowledge, designing a suitable automated innovization procedure, and finally interleaving human-provided and machine-extracted knowledge. We show that such a framework can achieve faster convergence across a variety of practical optimization problems. Some future research directions are also discussed.
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Title: An investigation of cerebellar morphology in childhood stuttering
Creator: Johnson, Chelsea Anna
Date: 2022
Collection: Electronic Theses & Dissertations
Description: While many studies have connected structural and functional cerebellar differences to developmental stuttering, there are limited studies of cerebellar gray matter morphology in young children who stutter. These examinations include small sample sizes of children and use morphometry methods that might not be best suited for examining the cerebellum (e.g., Chang et al., 2008). This dissertation examines how the structure of specific cerebellar lobules differs in a larger cohort of children who...
Show moreWhile many studies have connected structural and functional cerebellar differences to developmental stuttering, there are limited studies of cerebellar gray matter morphology in young children who stutter. These examinations include small sample sizes of children and use morphometry methods that might not be best suited for examining the cerebellum (e.g., Chang et al., 2008). This dissertation examines how the structure of specific cerebellar lobules differs in a larger cohort of children who stutter and children who do not stutter as well as in persistent and recovered children who stutter. These data will provide evidence to better inform predictions of how the morphology of cerebellar areas are likely involved in aspects of speech motor control in developmental stuttering. In this study, gray matter morphology of the cerebellum was examined in children who do and do not stutter using voxel-based morphometry and a specialized toolbox and atlas for the cerebellum (Diedrichsen, 2006). Here we examined cerebellar gray matter volume (GMV) based on structural MRI data from children who stutter and children who do not stutter, 116 preschool-age children (stuttering N= 57) between the ages of 3-5 years, and a school-age cohort of 72 children (stuttering N=37) six years of age and up. This dissertation is the first study to examine cerebellar GMV in a large group of children who stutter using a specialized toolbox and atlas for the cerebellum. Results from this study showed that there were no overall significant group differences of lobular GMV between the stuttering and non-stuttering groups in any of the groups of children. There were significant age-related associations, however, that differentiated children who do and do not stutter in specific age ranges. In particular, the following cerebellar lobules differed significantly in GMV between children who do and do not stutter with age: 1) cerebellar lobule VII, which may correspond with cerebellar functions that support speech planning, 2) lobule VIII, which has been linked to various functions including corrections during perturbation studies, and 3) lobule IV which has been reported to be involved in feedforward control speech motor control processes. Notably, GMV of cerebellar lobule VI was associated negatively with Stuttering Severity Instrument (SSI) score in preschool-age persistent children who stutter. Associations between SSI score and GMV in cerebellar lobule VI may mean that feedforward control mechanisms are associated with the frequency of stuttering in children who stutter. In summary, significant findings of this investigation indicate that 1) children who do and do not stutter do not show an overall difference in cerebellar GMV, 2) GMV of the cerebellum is associated with SSI score, 3) age-related differences in GMV in the cerebellum differentiate children who do and do not stutter. The results from this study indicate that feedforward control is associated with disfluencies while age-related variations of cerebellar areas that may support both the feedback and feedforward control pathways are connected to aspects of stuttering, such as age.
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Title: Analysis of Positional Bias Within Multiple Stimulus Without Replacement Preference Assessments
Creator: Miranda, David Ray Gutierrez
Date: 2021
Collection: Electronic Theses & Dissertations
Description: Positional bias is a pattern of responding to a specific location that can be influenced by response effort and/or prior learning history. Within the contexts of preference assessments, positional bias create additional variables that make ascertaining true preferences within a preference assessment more difficult. Prior research on positional bias within preference assessments have focused primarily on its use in paired stimulus assessments due to the complex nature of the multiple-stimulus...
Show morePositional bias is a pattern of responding to a specific location that can be influenced by response effort and/or prior learning history. Within the contexts of preference assessments, positional bias create additional variables that make ascertaining true preferences within a preference assessment more difficult. Prior research on positional bias within preference assessments have focused primarily on its use in paired stimulus assessments due to the complex nature of the multiple-stimulus without replacement preference assessment. The present study is a secondary analysis that utilized four different methods to measure side bias and center bias for 19 young children with autism spectrum disorders. Results indicate that participants had varying degrees of biased responding but collectively engaged in little biased responding. Present study includes discussion of general patterns of responding, an analysis of the four methodologies, and general recommendations for the application of these methodologies.
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