This is a summary report on some existing results and methods regarding the problem of determining the basins of attraction of dynamical systems (in particular, two-dimensional diffeomorphisms) when there is a coexistence of attractors. Based on the work of Helena Nusse and James Yorke, it presents existence and characterization results for a certain kind of basin boundaries (namely, the Wada boundaries). The key feature of their approach is to redefine the idea of a basin boundary by introducing the notion of a `basin cell', which bypasses the problem of exactly locating the attractor of a system, which is often either not well-defined or hard to locate in practice. Moreover, the basin cells and their boundaries are characterized by utilizing the stable and unstable manifolds of the system, which are easier to locate by numerical methods, and thus their method provides both numerically verifiable characteristics and algorithms for computation. / text

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We investigate the role of boundary layer forcing and surface heterogeneities on the intensity and spectral distribution of the convective circulations of an idealized convective system. Our ultimate goal is to further the understanding of atmospheric convection. However, we depart from realistic atmospheric convection and study an idealized convective system known as the Rayleigh-Benard model in two dimensions. We extended the classical Rayleigh-Benard model to include the effects of boundary heterogeneities. These effects are included, inparticular through a sinusoidally variable surface temperature. In this idealized model, the Rayleigh number plays the role of convective available potential energy (CAPE) in atmospheric convection, while the boundary heterogeneities in the temperatureplay the role of boundary layer forcing. In particular, we study the effects of boundary forcing on the intensity and spectral distribution of convective circulations in great detail.We consider the problem in the linear and weakly nonlinear regimes. In the linear regime, we find an analytical solution for Rayleigh-Benard convection with boundary forcing. We show that the inclusion of periodic boundary forcing causes discontinuities in the linear solution when critical conditions are approached. In the nonlinear regime, we find the solution by direct numerical simulation. The nonlinearities not only remove the discontinuities, but also lead to the appearance of non-trivial modes in the solution.The classical modes appear when the Rayleigh number issupercritical and the amplitude of the boundary forcing is small. Modes governed by boundary forcing dominate when its amplitude is large. Non-trivial modes with wavenumbers different from either the classical or the boundary modes appear only for intermediate values of the boundary forcing. The transitions between regions dominated by the classical Rayleigh forcing, mixed forcing, andboundary forcing depend on the Rayleigh number and the wavenumber of the boundary forcing. We conclude that boundary forcing has non-trivial effects on convective circulations. This result might have important implications for atmosphericconvection. Indeed, it suggests that atmospheric convection over the relatively homogeneous oceans would have different spectral distribution compared to that over heterogeneous land surfaces. This result is consistent with observations.

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Steps on surfaces have long been explored for their own sake, and exploited as growth mediators. However, another type of linear surface defect - the domain boundary - has been largely neglected. Here we introduce domain boundaries of the 5x5 dimer-adatom-stacking fault reconstruction, explore their properties and demonstrate that they too can be used to mediate growth in a useful manner. When a thin layer of Ge is grown on Si(111) lattice strain induces the overlayer to reconstruct as Ge5x5. Using solid phase epitaxy, many domains of 5x5 can be grown. The domain interiors have excellent order, and with careful annealing, the boundaries that separate them are straight and uniform. Well-ordered boundaries propagate along the two high symmetry directions <1 -1> or <1 1> and are called A-type or B-type respectively. Boundaries of the second type are unique to Ge5x5. Registration with the substrate restricts the misfit between domains to discrete possibilities which are labeled according to a modified version of the system used for domain boundaries of Si(111)7x7. The distribution of observed boundary types is strongly peaked and reflects the relative energies of boundaries of different character. The expanded labeling scheme can be used to sketch the kinetic processes which lead to the distribution peaks. The dominant boundary by far is the one known as B[-2 2], which accounts for almost half of all observed boundaries. The atomic structure for this type of boundary has been established as a truncated 7x7 unit cell. Thus, these boundaries are linear arrays of quasi-7x7 embedded in a sea of 5x5. On the Si(111)7x7 surface the Group 13 elements, when deposited at sub-ML coverages and low temperatures, form magic clusters. The perfect uniformity and precise registration that earns them the moniker ‘magic’ make these clusters unusual among self-organized atomic scale objects. The clusters that form on 5x5 lack the uniformity of their counterparts on 7x7. However, with many domains, deposited In or Ga segregate to the quasi-7x7 B[-2 2] boundaries and there form magic clusters. The boundary thus acts as a template for growing straight lines of precisely spaced, atomically identical, nanoscale clusters. / Thesis (Ph.D, Physics, Engineering Physics and Astronomy) -- Queen's University, 2009-07-29 08:50:16.874

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When accidents occur, citizens often are the real first responders. This has been acknowledged and studied from an international perspective, particularly in relation to large crises and disasters, but remains relatively unstudied from a Swedish perspective. This thesis takes its point of departure from people who have been emergency callers or witnesses to traffic accidents, studying their actions and interactions at the scene of an accident in terms of boundaries, positioning and emergence. The aim of this thesis is to study how people’s actions in a specific situation are affected by their interactions with both real and imagined others and how their actions are affected by the spatial context. The thesis consists of four individual studies that relate differently to the main aim of the thesis. The first study focuses on first responders’ options to act in a place that simultaneously is the workplace of emergency personnel: the incident site. This study shows how first responders’ options to act are governed in large part by their interaction with emergency personnel and their boundary practices at the incident site. In this study, we apply theories of boundary practices from Nippert-Eng and the concept of boundary work from Gieryn to explain how emergency personnel control their place of work through boundary practices and through that process control those first responders who are present at the site. In other words, people’s actions at the incident site are affected by both the social and the spatial context. The second study focuses on a limited selection of first responders: those who have placed emergency calls. Through interviews with callers and transcriptions of their emergency calls, this study explores how the callers frame their decision to stop and place the call through different presentations of self. These presentations are constructed through moral positioning, in which the callers position themselves and their actions in relation to both real and imagined others. Thus, the callers also construct normative accounts of what is considered a “preferable” and “non-preferable” way to act at the scene of an accident. The third study takes its point of departure from theories and previous research on emergence because they have been used by disaster sociologists to explain how citizens are the real first responders to crises and disasters. Through the concepts of emergent behavior and emergent norms, papers in this research field have argued that people in these situations act according to “new and not-yet-institutionalized behavior guidelines”. In this study, I argue that emergence, in other words, citizens as the real first responders, is also present in everyday emergencies. Through the narratives of citizen first responders, I explore how they frame their actions through different normative narratives. These normative narratives are not necessarily emergent, however. Rather, the interviewees use past experience and presentations of self to justify their actions at the scene of an accident. The fourth study is an ethnographic reflection of the researcher’s place-bounded identity in a field study that revolves around several different places. Rather than focusing on a story of first responders, this study focuses on the researcher’s, i.e., my own, story from the scene of an accident, the fire truck and the fire station. What I have been able to study through these different studies are stories of actions rather than “actual” actions or behaviors. In these stories, it becomes clear that first responders relate to both a social and spatial context as they provide accounts of their actions at the scene of an accident. They relate to a social context because they frame their actions through their interactions with different actors and position themselves in relation to those actors—and in relation to a spatial context. That is, they perform their actions in a place that is someone else’s place of work, with jurisdictional claims of both legitimacy and control. In summary, this thesis contributes a deeper knowledge of how citizen first responders interpret, understand and tell the story of their actions at the scene of an accident. The contribution considers the fact that citizen first responders are something of a “blind spot”, not only in the field of emergency research but also for emergency personnel who do not always acknowledge the experience of first responders at the scene of accidents.

This study traces spatial and temporal disturbances in the modem short story structure. Edgar Allan Poe's "indefinitiveness" and Kenneth Burke's "actualization" serve as historical foundations for this investigation, which leads to contemporary frameworks proposed by such theorists as Gerard Genette, Umberto Eco, Wolfgang Iser, Paul Ricoeur, Peter Brooks, James Phelan, and Susan Sniader Lanser. In particular, I explore how effect operates as a predominant concern of short fiction. Short fiction is a rhetorical interaction encumbered by spatial and temporal constraints, and its narrative teleology is necessarily disrupted by rhetorical techniques. Narrative's boundaries are purposefully violated, its tempo twisted and contorted, exposing a purposeful tension in the rhetorical engagement of author, text and reader. Instabilities crafted within the text disrupt time-space expectations of readers.Importantly, effect is perceived as a rhetorical device within short fiction, and so in this study the text serves as a site of transference privileging equally writer and reader. Conditions of possibility and understanding are invested in the text by the author through techniques of spatial disruption and temporal discontinuity, and then reinvested in the reader by the narrative through the text's generation of uncertainty. Short fiction serves as an invitation by the author for the reader to construct explanations; devices work to disrupt the time-space constraints of the genre, establishing as they do a narrative contract between author and reader that is resolved in and from the text.Burke considers this to be shaping prose fiction to the author's purposes, an act which "involves desires and their appeasements" - and one which purposefully aims for a particular effect. But what are the limits of purposefulness in short fiction? I examine both textual effect and reader affect, relying particularly on Iser and Eco, and turn to Brooks in conclusion to summarize the role of desire in and from the text, and to Phelan to critique the place of rhetoric in establishing and maintaining that desire. My analysis discloses that time-space disruption, employed as a rhetorical strategy by short story writers, serves to heighten rather than threaten the mediated engagement of writer/text/reader in short fiction, producing a measured effect. / Department of English

Individuals, communities, non-government organizations and governments are in constant pursuit of intelligent responses to the complex socio-environmental challenges they encounter. The capacity to respond effectively to these contemporary challenges is deeply dependent on the presence of effective governance processes. Governance scholarship has typically been limited to individual elements such as frameworks (hierarchical or market or network), tools (e.g., regulation) or actors (e.g., government). The goal of this thesis is to characterize and explain transformations in water governance in order to offer insight into how more effective governance processes can be created. Transformations in governance speak to the dynamic nature of governing, and highlight the consistent push and pull between, and amongst, the various components at play. Components include actors, formal and informal structures, and the social, economic and environmental contexts in which governance is embedded. Critically each of these components also exists and has influence at multiple levels, adding to the complex and dynamic nature of governance. This research argues that the core elements (frameworks, tools, actors) should be examined individually, as well as collectively, and within context of the various components in order to obtain a holistic perspective on governance process. This holistic perspective is necessary if we are to garner a true understanding of how governance is ultimately designed, contested and transformed. The research focuses on a large-scale water governance case in southern Ontario that is governed by its own provincial legislation ??? the first of its kind in Canada. The research examines governance frameworks as situated within the broader architecture, tools, and actor dynamics in the Lake Simcoe watershed and how they evolved over a 30-year period. Interviews, archival research, surveys and social network analyses were utilized in a mixed methods approach. The first governance element examined in this thesis is the architecture of the entire system over the 30 year time period. Rather than conduct a narrow analysis of an individual governance framework in a select period of time, the research takes a high level perspective to identify the transitions between governance frameworks, and the social, economic, and environmental tensions and drivers that initiated change. Particular value is offered by the use of social network analysis to visually identify the structure and statistically evaluate the governance framework at multiple phases in the research period. The second element of governance, tools, is then assessed. Specifically, the utility of a watershed boundary for water governance is examined. The thesis argues that the watershed boundary has value, but should be applied in limited and focus ways, and greater attention should be given to governance processes that transcend the watershed boundary. The final element examined is actors. Early in the thesis, focus is given to the role of government, but in the final section particular attention is given to the role of non-government actors. The research describes how the role and activities of non-government actors has advanced beyond late 20th century approaches, where recent trends display more innovative and entrepreneurial characteristics. The research offers nine important insights for theory and practice in water governance. (1) Governance processes have the potential to be flexible, adaptive and responsive. (2) A reduced presence of government does not always hold back processes of governance. (3) Existing tools can be re-imagined for new processes. (4) Non-government actors have agency (5) Give attention to individual knowledge and capacity through a distributed governance approach (6) Give attention to time and the building of scientific knowledge (7) Give attention to need for effectively facilitated processes (8) Give attention to emerging opportunity (9) Permits space for creative destruction. Collectively, the findings from this research further develop scholarship on the individual elements of governance, as well as speak to the transformations in water governance as a whole.

This qualitative study explores how roles are constructed within interprofessional health care teams. It focuses on elucidating the different types of role boundaries, the influences on role construction and the implications for professionals and patients. A comparative case study was conducted with two interprofessional primary health care teams. The data collection included a total of 26 interviews (13 with each team) and non-participant observations of team meetings (2-3 meetings at each site). Thematic analysis was used to analyze the data and a model was developed to represent the emergent findings. The role boundaries are organized around interprofessional interactions (autonomous-collaborative boundaries) and the distribution of tasks (interchangeable-differentiated boundaries). Salient influences are categorized as structural, interpersonal and individual dynamics. The implications of role construction include professional satisfaction and more favourable wait times for patients. The elements in this conceptual model may be transferable to other interprofessional primary health care teams. It may benefit these teams by raising awareness of the potential impact of various within-team influences on role construction.