Toward a theory of cultural transparency : elements of a social discourse of the visible and the invisible

This dissertation develops a number of analytical categories for investigating what people know about the world in which they live. It is an attempt to open up a universe of discourse about learning that does justice to the social character of human life. The argument of the dissertation is developed in the context of an ethnographic study of a claim processing center in a large insurance company.The basic argument is that knowledge does not exist by itself in the form of information, but that it is part of the practice of specific sociocultural communities, called here "communities of practice." Learning then is a matter of gaining a form of membership in these communities: this is achieved by a process of increasing participation, which is called here "legitimate peripheral participation." Learning thus is tantamount to becoming a certain kind of person.Visible objects such as artifacts, symbols, language, gestures, also belong to the practice of these communities. Therefore, seeing the cultural significance of these objects, something I call "cultural transparency," requires access to the practices to which they belong. This in turn requires membership in the relevant communities. The relation between artifacts and persons, which one may describe as understanding or not understanding, is therefore never a direct relation between them, but one that is mediated by a person's specific forms of membership in specific communities and by an object's being part of the social practices of some communities, which may or may not be the same. To the extent that these communities are different, such an object can be called a "boundary object" that mediates the articulation of these communities. This dissertation investigates the nature of one such object and analyzes both the relations that it can mediate and the forms of knowledge and senses of self that can result.The availability of an analytical discourse such as the one explored here is important because technological advances and the division of labor imply that we deal more and more with objects that do not primarily belong to our communities of practice. This is especially relevant to the design of computer systems

Exploring the episodic structure of algebra story problem solving

This paper analyzes the quantitative and situational structure of algebra story problems, uses these materials to propose an interpretive framework for written problem-solving protocols, and then presents an exploratory study of the episodic structure of algebra story problem solving in a sizable group of mathematically competent subjects. Analyses of written protocols compare the strategic, tactical, and conceptual content of solution attampts, looking within these attempts at the interplay between problem comprehension and solution. Comprehension and solution of algebra story problems are complimentary activities, giving rise to a succession of problem solving episodes. While direct algebraic problem solving is sometimes effective, results suggest that the algebraic formalism may be of little help in comprehending the quantitative constraints posed in a problem text. Instead, competent problem solvers often reason within the situational context presented by a story problem, using various forms of "model-based reasoning" to identify, pursue, and verify quantitative constraints required for solution. The paper concludes by discussing the implications of these findings for acquiring mathematical concepts (e.g., related linear functions) and for supporting their acquisition through instruction

The effect of multiple knowledge sources on learning and teaching

Current paradigms for machine-based learning and teaching tend to perform their task in isolation from a rich context of existing knowledge. In contrast, the research project presented here takes the view that bringing multiple sources of knowledge to bear is of central importance to learning in complex domains. As a consequence teaching must both take advantage of and beware of interactions between new and existing knowledge. The central process which connects learning to its context is reasoning by analogy, a primary concern of this research. In teaching, the connection is provided by the explicit use of a learning model to reason about the choice of teaching actions. In this learning paradigm, new concepts are incrementally refined and integrated into a body of expertise, rather than being evaluated against a static notion of correctness. The domain chosen for this experimentation is that of learning to solve "algebra story problems." A model of acquiring problem solving skills in this domain is described, including: representational structures for background knowledge, a problem solving architecture, learning mechanisms, and the role of analogies in applying existing problem solving abilities to novel problems. Examples of learning are given for representative instances of algebra story problems. After relating our views to the psychological literature, we outline the design of a teaching system. Finally, we insist on the interdependence of learning and teaching and on the synergistic effects of conducting both research efforts in parallel

Systems Convening: A Crucial Form of Leadership for the 21st Century

Social learning across complex landscapes requires a certain kind of leadership, which we have called systems convening. Many people do this kind of work without any label, often unrecognized, and sometimes not even particularly aware that they are doing it. A systems convener or systems convening team sets up spaces for new types of conversations between people who often live on different sides of a boundary. For example, a geographic, cultural, disciplinary, political, class, social boundary. These conveners see a social landscape with all its separate and related practices through a wide-angle lens: they spot opportunities for creating new learning spaces and partnership that will bring different and often unlikely people together to engage in learning across boundaries. A systems convener takes a “landscape view” of wherever they are and what they need to do to increase the learning capability of that entire landscape – rather than simply the capability of the space they are standing in. Importantly, a systems convener is someone who has enough legitimacy in different worlds to be able to convene people in those different worlds into a joint conversation. This book draws on interviews with 40 systems conveners who are using this approach around the world, working on diverse issues ranging from improving government transparency to enhancing cancer care

Boundaries and boundary objects:An evaluation framework for mixed methods research

While mixed methods research is increasingly established as a methodological approach,researchers still struggle with boundaries arising from commitments to different methods and paradigms, and from attention to social justice. Combining two lines of work - social learning theory and the Imagine Program at the University of Brighton - we present an evaluation framework that was used to integrate the perspectives of multiple stakeholders in the program's social interventions. We explore how this ‘‘value-creation framework'' acts as a boundary object across ‘‘boundaries of practice,'' specifically across quantitative and qualitative methods, philosophical paradigms, and participant perspectives. We argue that the framework's focus on cycles of value creation provided the Imagine Program with a shared language for negotiating interpretation and action across those boundaries

Panchromatic engineering for dye-sensitized solar cells

The dye-sensitized mesoscopic solar cell has been intensively investigated as a promising photovoltaic cell. Its ecological and economical fabrication processes make it attractive and credible alternative to conventional photovoltaic systems. In contrast to the latter design, the DSC approach separates tasks of light absorption and charge transport. The primary step of light absorption is performed by a sensitizer anchored to the surface of a wide band gap semiconductor. In order to reach a high conversion efficiency, the first requirement is that the sensitizer should absorb as much as possible of the incoming sunlight. Strategies for achieving panchromatic response in dye-sensitized mesoscopic solar cells are discussed