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Play dates are inclusive opportunities outside of school for young children to practice skills with their playmates. Children with autism spectrum disorders (ASD), however, have challenges socially interacting with typically developing playmates. Previous research supports that parents hold great promise as facilitators to support their children with ASD in social areas. This survey aimed to obtain perspectives of parents of young children with and without autism on their experiences with play dates. Specific areas examined were parent, child, and playmate characteristics, play characteristics, perceived barriers and benefits, and parent willingness to facilitate play dates and receive training. Results revealed that parents of children with ASD had a significantly lower frequency of play dates than the parents of children without ASD. There was not a significant difference in reported number of playmates between the two groups of parents. There was a statistically significant difference in perceived barriers between the two groups; parents of children with ASD scored significantly higher on barriers. However, there was no statistically significant difference between the parent groups on perceived benefits. The results showed that the majority of parents are interested in having a child with ASD as a playmate. Based on their open-ended responses, most indicated that they would not mind any characteristics or differences as long as parents communicate with one another, and children get along well and have fun. Some parents also mentioned every child is different and their responses were not autism specific, rather child specific. The majority of parents mentioned concerns about safety of the children and potential aggressive behaviors as well as concerns about differences in social-communication, language skills and empathy. The results also showed that parents of children without ASD were less likely to be willing to facilitate if they have other children at home. White parents and parents who have other children at home to care for were more willing to receive training. Disruptive, disconnection and interaction behaviors were significantly correlated with parent status. The autism group was more likely to be associated with disruptive and disconnection behaviors while interaction behaviors were more likely to be associated with parents of children without ASD. There was a significant relationship between disconnection behaviors and frequency of play dates. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

In this dissertation, I explore how top executives’ and directors’ embeddedness in corporate elite networks within and between organizations’ boards of directors influence organizational strategy and policy. In the first study, I conduct a comprehensive review of the governance literature using both a traditional narrative approach as well as a bibliometric main path analysis, which traces the development and diffusion of scholarly knowledge on corporate elite networks. In the second study, drawing from network theory and behavioral governance research, I introduce a methodology that allows researchers to model intraboard networks by measuring the strength of ties among members of boards of directors based on objective formative indicators of the constructs of social similarity, social status, social exchange, and social history. Next, I use this technique to explore the antecedents and consequences of intraorganizational network characteristics of boards. Finally, in the third study, I examine the joint influence of interlocking directorates and intraorganizational networks of boards of directors on interorganizational imitation of corporate strategic activity. Results show that directors’ centrality within a focal organization’s board and those of its alters are important predictors of interorganizational imitation of corporate strategic activity. I contribute to the strategic management and organization theory literatures by advancing our understanding of the relationship of corporate elite networks with organizational strategy and policy, and by introducing a new approach to modeling directors’ networks in corporate governance research.

When a premixed flame front spreads in a narrow pipe, wall friction continuously distorts the flame shape. As a result, the flame front acquires a larger surface area, consumes more fuel per unit time and, thereby, propagates faster. While this mechanism of flame acceleration due to wall friction has widely been studied, especially within the last decade, the analytical and computational studies were mostly devoted to equidiffusive flames, where the Lewis number, defined as the thermal to mass diffusivity ratio, is unity, Le = 1. However, in reality thermal and mass diffusion are typically not balanced, especially in rich and lean mixtures. Hence, the micro-scale, diffusional-thermal effects may appear comparable with macro-scale phenomena such as wall friction. The present work sheds the light on the dynamics and morphology of Le ≠ 1 flames in channels. Specifically, it studies, by means of computational and analytical endeavors, how the interplay of finite flame thickness, stretch effect and the thermal-molecular diffusion influence the overall flame acceleration scenario. It is shown that Le > 1 flames accelerate slower, due to an effective thickening of the flame front. In contrast, Le < 1 flames exhibit faster acceleration due to effective flame channeling and other morphological deformations resembling the diffusional-thermal (DT) instability. The analysis also incorporates the internal transport flame properties into the theory of flame acceleration due to wall friction, by means of the Markstein number, Mk, that characterizes the flame response to curvature and stretch. Being a positive or negative function of thermal-chemical combustion parameters, such as the thermal expansion ratio and the Lewis and Zel'dovich numbers, the Markstein number either restrains or promotes the flame acceleration. While Mk may substantially facilitate the flame acceleration in narrow channels, this effects diminishes with the increase in the channel width. The analysis is accompanied by extensive numerical simulations of the Navier-Stokes and combustion equations, which clarify the impact of the Lewis number on the flame acceleration. It is obtained that, for Le lower than a certain critical value, at the initial stage of flame acceleration, globally-convex flame fronts split into two or more "fingers", accompanied by a drastic increase in the flame surface area and associated enhancement of the flame acceleration. Later, however, the flame fingers meet, promptly consuming the troughs, which rapidly diminishes the flame surface area and moderates the acceleration. Eventually, this results in a single, globally-convex flame front that keeps accelerating. Overall, the thermal-diffusive effects facilitate the flame acceleration scenario, thereby advancing a potential deflagration-to-detonation transition.