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The purpose of this study was to examine the second language development of a native-speaker of Spanish learning English over a period of 15 months. More specifically, I explored the interaction of complexity (advanced forms of grammar and vocabulary), accuracy (grammatical and semantic), and fluency, commonly referred to as the CAF constructs. While findings in CAF literature tend to focus on one construct using experimental or cross-sectional studies (Bulté & Housen, 2012; Kormos & Dénes, 2004; Vyatkina, 2012), this case study investigated non-linear and interconnected CAF development, periods of fluctuation, and the effects of motivational factors on 14 variables. In order to explore the data as a system developing simultaneously, Complex Dynamic Systems Theory (CDST) (Larsen-Freeman, 1997; 2006) was applied as the theoretical framework. Through CDST’s theoretical lens and the tools developed for it (Verspoor, de Bot & Lowie, 2011), I found that knowledge variables (lexical diversity, accuracy, and elaboration) maintained consistent correlations, whereas their relationship with fluency variables (speed, repairs, and pauses) changed based on the cognitive strain the learner was experiencing at the time. I also found that the learner shifted his focus between the knowledge variables and that the complexity and accuracy variable on which he chose to focus appeared to be affected by changing motivational factors. / Applied Linguistics

<p> Software Evolution is unavoidable because software systems are subject to continuous change, continuing growth and increasing complexity. As software systems become mission-critical and large in size, the complexity in software development is now focused on software evolution rather than construction. In this work, we view a software system as an entity that is evolving throughout its lifetime, during development and maintenance. Based on a broad survey of software evolution approaches, we propose an architecture-based solution for software evolution, which is defined in terms of evolution specific operations on architectural elements, that is, adding, removing, replacing components and (or) connectors, transforming configurations according to the required changes. In our view of software architectures, connectors are more likely to change since they are the architectural elements which reflect business rules. This work is focused on the evolution of connectors in architectures describing detailed design. Coordination contracts are introduced by Fiadeiro et al. as a realization of connectors at this detailed architecture level, which enables a three-layer architecture to separate concerns of components, connectors and configuration during evolution. Furthermore, to constrain the evolution in a predictable direction, we have established a matching scheme for justifying behavioral relationships between coordination contracts by specification matching based on pre- and postconditions of contracts and methods. A number of specification matches, with various degrees of similarity between the evolved and evolving contracts, have been developed for system behaviors after evolution operations. Case studies are exhibited give a better understanding of these matches.</p> / Thesis / Master of Science (MSc)

As part of an on-going process of centralizing control of government science and technology (S&T) after World War II, in 1966 the Navy went through a major reorganization that was intended to centralize the strategic management of the Navy laboratory system. This centralization was to be accomplished by placing the major Navy research and development activities in a single systems command - the Naval Material Command - and establishing the position of Director of Navy Laboratories. Organizational studies and reorganizations continued for the next 25 years until the Naval Material Command and the Director of Navy Laboratories were disestablished in 1985 and 1991, respectively. This dissertation is, in part, an historical study of the Navy from 1946 to 1966 that focuses on the bureaus and laboratories. It summarizes the organizational changes related to strategic management and planning of science and technology. The 1966 reorganization was a critical event because it created the first formal Navy laboratory system. It is proposed that the 1966 reorganization was not successful in centralizing the strategic management of the Navy laboratory system. Classical organization theory offers an explanation of this failure. What can complexity theory add? The overarching contribution is in recognizing that a "Navy Laboratory System" existed before one was formally established in 1966. This argument is developed by considering two specific aspects of complexity theory. First, there is the notion that strategic management of the laboratory system resulted from the complex interactions of the smaller units that comprise the system (rather than the result of organization and process choices by senior leadership). Second, there is the theory that an organization will exhibit different behaviors at different times or in different parts of the organization at the same time. This translates into the idea that at particular times and places, the formal structure was dominant in strategic management, but at other times the "emergent" organization was dominant. In fact, if power law theory is applicable, then the periods of stability (where the formal structure was dominant) ought to be more prevalent than the turbulent periods where the emergent organization was dominant in strategic management. This case is made by describing agent-based models of the Navy laboratory system at two points in time and using them to identify the expected performance characteristics of the system. Historical and organizational artifacts are then used to make the case that the postulated system existed. / Ph. D.

Within the current national atmosphere of accountability and high-stakes testing, many teachers are changing their instruction to return to more traditional strategies that emphasize rote memorization. As a result, classroom curriculum and student learning are narrowing. This study sought to explore the potential of graphic organizers as an instructional strategy to expand student content knowledge beyond rote memorization to include more organized, complex, meaningful learning. For the purpose of this study, graphic organizers are described as visual displays of concepts, their component parts, and the relationships among their parts. This study was conducted over a six week period in a third grade classroom in a rural elementary school in Virginia. Ten focus students were identified for in-depth data collection on their learning process as recorded during science instruction. Although existing research strongly supports graphic organizer effectiveness as an instructional strategy toward general student achievement, little is known about the type of learning they support or the process by which students' knowledge develops. Thus, this research utilized qualitative methodological strategies in order to investigate this process. Data collection methods included field notes, student artifacts, and participant interviews. Constant comparative methodology was employed to analyze data. The theoretical framework of constructivism, espousing that newly acquired information is connected to prior knowledge forming complex, organized networks of conceptual understanding, guided this qualitative study. Findings resulted in emergent themes including student motivation, simplicity, efficiency, visual hierarchical organization, reconstructing knowledge, and cooperative socialization. Documentation of the learning process as opposed to a comparison of pre/post measurements clearly indicated that student thinking gradually became more complex and organized in nature. As students worked with graphic organizers, and participated in study activities, their knowledge moved from a form of listing facts to resemble more complex, interconnected networks. Implications of this study for practice include appropriate instruction and practice for students with graphic organizers as a strategy and a tool, value as an assessment tool, and potential for use with complex classroom populations. Suggestions for future research are given for teacher training on how to use graphic organizers effectively, interdisciplinary use of graphic organizers within one context, potential benefit for struggling and diverse learners, a continuing focus on process as opposed to product, and an examination of the connection between graphic organizer activities and sorting. / Ph. D.

Bacteriophages, or phages, have historically been distinguished by their small sizes and relatively simple genomes compared to cellular life. Discoveries over recent decades, however, have uncovered remarkably large phages, called jumbo phages, which are defined by having genomes over 200 kilobases and contain virion sizes comparable to small bacteria. These exceptionally large phages prompt questions on how such complexity emerges and persists in the virosphere, when being simple is so successful with shorter replication times and larger burst sizes. This dissertation aims to address these knowledge gaps by examining the evolutionary and ecological contexts of genomic and community-level complexity of phages using a variety of metagenomic datasets, namely from marine environments. Toward understanding the coexistence of jumbo phages among smaller phages, Chapter 1 provides a literature review on jumbo phage diversity, associated fitness tradeoffs of largeness, and predictions on which environments or ecological conditions may be enriched in jumbo phages. Chapter 2 assesses the evolutionary context giving rise to complex phages, by examining a group of phages that encode a multi-subunit DNA-dependent RNA polymerase homologous to that of cells. This gene fortuitously enabled phylogenetic analyses of phages with cellular life and revealed that these phages likely emerged prior to the divergence of bacteria and archaea, rather than acquiring the gene from their hosts more recently. Chapter 3 examines the biogeography of genomic complexity in the ocean by identifying and comparing groups of jumbo phages in seawater metagenomes of the global ocean. This work revealed that jumbo phages with distinct replication machinery also have distinct distributions, with some groups more common in surface waters than deeper waters and vice versa. Chapter 4 compares drivers of phage complexity at the community level (based on diversity) with the drivers of prokaryotic community diversity by examining seawater metagenomes from contrasting ecosystems off the coasts of the Isthmus of Panama. Despite phages' requiring their hosts to replicate, the results show that factors increasing phage and prokaryotic diversity do not always align. This discrepancy highlights the role the environment also plays in governing virus-host interactions, such as impacting dispersal ranges and adsorption efficiency. Collectively, this dissertation addresses how, what, and where complexity in the virosphere occurs using culture-independent methods and contributes to our growing understanding of the breadth of viral diversity and ecology. / Doctor of Philosophy / While many viruses cause disease and threaten animal and plant health, most viruses on Earth infect microbes, which are tiny, single-celled organisms like bacteria. These viruses can be used to kill harmful bacteria, like certain Escherichia coli (E. coli), and they impact the movement of nutrients in ecosystems because microbes like algae form the basis of food webs in the sea. While most known viruses are very tiny, larger viruses have been recently discovered over recent decades. Being a big virus can be very costly, as it takes more resources for these viruses to replicate or reproduce. Despite these costs, big viruses can be found in many environments around the world, such as the human intestine and the deep sea, which suggests that being large as a virus might be useful in some circumstances. This dissertation aims to uncover how, why, and where being large as a virus is most successful. This research specifically focuses on a group of viruses called phages, which are viruses that infect microbes called bacteria and archaea. Larger phages, those with genomes four times the size of most other phages and twenty times the size of the COVID19 virus, are called jumbo phages. Chapter 1describes the diversity of jumbo phages, what advantages they may have over smaller phages and which environments these advantages may be most helpful. Chapter 2 examines how complex phages evolved by analyzing a group of phages that have a special gene that is also found in all cellular life (microbes, plants, and animals). The evolutionary history of this gene suggests that phages possessed this gene prior to the emergence of major cellular groups (bacteria, archaea, and eukarya), rather than stealing this gene from their host more recently. Chapter 3 uncovers where different types of jumbo phages are most prevalent in the ocean; some are more common in surface waters, and some are more common in deeper waters. Finally, Chapter 4 aims to understand the complexity of phage communities in terms of where phages are most diverse. We found they are more diverse in habitats where bacterial diversity is lower, which is unexpected but shows that the environment plays a major role in virus-host interactions. Overall, this dissertation uncovers the diversity, distribution, and origins of complexity in phages and phage communities, so that we can better understand how they impact the environment and affect microbes that power ecosystems.

No / The rise of networked social movements contesting neo-liberal globalization and protesting the summits of global finance and governance organizations has posed an analytical challenge to social movement theorists and called into question the applicability to this global milieu of the familiar concepts and heuristics utilized in social movement studies. In this article, we argue that the self-defining alter-globalization movement(s) might instead be engaged with as an expression and effect of global complexity, and we draw upon a `minor¿ literature in social movement studies that includes Gregory Bateson, Gilles Deleuze and Alberto Melucci to illustrate our claims. This article uses a Deleuzian reading of complexity to describe the phase space of the `movement of movements¿, and its perturbation of global civil society through the iteration of sense-making processes (reflexive framing) and the exploration of singularities inhering in social movement `plateaux¿. Those transnational gatherings, protests and social forums facilitated by computer-mediated communications and the advent of unprecedented mobility which constitute a `shadow realm¿ that remains largely invisible to political exchange theories operating within the conceptual confines of the nation-state.

Systems engineering has many subdisciplines which would be useful to study in terms of complex system behavior. However, it is the interactions between a complex system and its operating environment which drive the motivation for this analysis. Specifically, this work introduces a new approach to assessing these interactions called "boundary resilience." While classical resilience theory measures a system's internal reaction to adverse event, boundary resilience evaluates the impacts such an event may have on the surrounding environment. As the scope of this analysis is quite large, it was deemed appropriate to conduct a case study to determine the fundamental tenants of boundary resilience. SpaceX's satellite Internet mega-constellation (StarLink) was chosen due to its large potential to impact the space environment as well as its size and complexity. This study produced two boundary resilience measures, one for local boundary resilience of a single component and one for the global boundary behavior of the entire system. The local metric measures the likelihood of an adverse event occurring at that boundary location as well as its potential to impact the surrounding environment. The global boundary resilience metric reflects a nonlinear relationship among the system components. / Doctor of Philosophy / It is no secret that the world and the systems which enable it to function have become increasingly complex in recent decades. This complexity has the potential to create both innovative uses as well as unplanned and unexpected behaviors in these systems. As they interact with their environment, complex systems can produce equally complex and unpredictable behaviors which have potential to have a negative impact on their environment. This work seeks to study one component of this behavior: resilience. Resilience usually measures a system's ability to continue providing a service in the event of a disruption, or to recover the ability to provide the service after some amount of time. Boundary resilience, on the other hand, takes the perspective of potential environmental damage caused by an adverse event, rather than damage to the system's functionality. This study uses a case study of the StarLink satellite constellation to examine this phenomenon. The outcome of the analysis shows that the size of a complex system negatively impacts its potential to cause damage to the surrounding environment, but increasingly mature components can mitigate this degradation.

A building is designed from a set of initial intended needs and uses. Yet, a building is a construction of its time and values that will stand for future generations long after the client and architect have faded. Therefore, an architectural intervention has a responsibility to the greater whole, the city. The subject of the thesis is the design of a house in Wilmington, North Carolina. The concern of the design is not the building as an object. The design is a proposal in architectural terms of what is necessary to render concrete the possibilities of a specific location that will serve our ever-changing daily needs, uses and desires with dignity. The proposal is based on an investigation of the fabric of place into which the building will be woven. That fabric consists of the natural landscape and the human interventions that have transformed it throughout its history. / Master of Architecture

In all past research, iconic memory shows a significant benefit over visual working memory for storage capacity of visual items. However, this effect has only been studied on simple items such as colors and letters. The goal of this thesis was to determine whether an iconic benefit also exists for visual stimuli with higher visual complexity, such as shapes and faces. Five experiments tested iconic and working memory capacity for complex face stimuli, intermediate-complexity shape stimuli, and simple color stimuli, as well as examining feature binding of objects in iconic memory. Results from these five experiments indicated that increased visual complexity of stimuli negatively impacts the iconic capacity benefit. High- and intermediate-complexity items had little to no iconic benefit, unlike all previously tested simple stimuli. Iconic memory may only be able to represent simple features, or may not be able to transfer complex information into visual working memory as quickly as simple information. Additionally, results showed that feature representations in iconic memory were sometimes bound into complex objects. The results of these five experiments challenge the traditional characterization of visual sensory memory as a precise snapshot; this early memory store may be more complex than a simple visual icon.