Boundary Layer Flow In Streamwise Concave Corners

Laminar boundary-layer theory has been correctly developed for streamwise corners using singular perturbation techniques. Theoretical predictions, however, do not compare well with experimental measurements due to the observed breakdown of flow stability and similarity. Both of these properties appear as basic assumptions of the boundary-layer theory, thereby providing needed simplification as well as imposing limitations upon the mathematical model.;Any theoretical investigation of similarity breakdown would require knowledge of the similar solution not only as an initial condition, but also for insight into how to proceed. Examination of the cross-flow behavior, which affects the onset of similarity breakdown, may suggest ways of formulating the problem without abandoning entirely the simplifying assumption of similarity.;The formulation of boundary-layer equations is reviewed beginning with time-independent Navier-Stokes equations. Tensor analysis is used so that the resulting equations are generally applicable to any similar flow configuration. A non-orthogonal Cartesian coordinate system is chosen to deal with streamwise concave corners (i.e. with corner angles less than 180(DEGREES)). Coordinate and flow-variable transforms are then used to define bounded quantities.;The computational procedures for obtaining the boundary conditions and solving the main equations are described briefly, noting some pitfalls that would hinder numerical computation. Results characterizing the mainstream flow and the secondary cross-flow are displayed and discussed for corners with angles of 30(DEGREES), 60(DEGREES), 90(DEGREES), 120(DEGREES) and 150(DEGREES). Ways to proceed with further investigation, while keeping the mathematical model simple, are then suggested

Mobilising recipiency: child participation and 'rights to speak' in multi-party family interaction

This paper discusses a child's participation in multi-party family interaction. Drawing from video-recordings of a family Christmas event, we examine instances where a child produces an initiating action that is unsuccessful at first in gaining the recipiency of the addressee(s). We show how for the child a regular issue might be not simply pursuing a response, but more generally mobilising the adult addressee's recipiency and engagement. The analysis describes the methods by which the child attempts to mobilise recipiency, how these attempts are responded to by the adults in the interaction, and how the child pursues recipiency when it is not gained in the first instance. Drawing on these empirical findings we examine the notion of children's ‘rights to speak’ in interaction, in particular reconceptualising it the along the lines of ‘rights to engage’. The paper contributes to understandings about children's communicative competence, as well as identifying more generic aspects of the management of multi-party interaction

Investigations of a combustible inertial launch design

The paper develops a subject of a combustible inertial (self-feeding) launch vehicle for nano and pico satellites. A part of the paper considers a flight of the rocket using ballistic, aerodynamic and thermal calculations. Another part describes experimental investigations of a laboratory-scale model of the rocket engine. Plans for future work and prospects of the self-feeding technology combined with pulse engine mode for microlaunchers and small satellite micro propulsion concludes the paper

Taking turns : bridging the gap between human and animal communication

Funding: a Sofja Kovalevskaja-Award of the Alexander von Humboldt-Foundation awarded to S.P. generously supported the project, as did a Max Planck Institute for Psycholinguistics Levelt Innovation Award awarded to K.H.K. and S.C.V., and a Max Planck Research Group awarded to S.C.V.Language, humans' most distinctive trait, still remains a 'mystery' for evolutionary theory. It is underpinned by a universal infrastructure-cooperative turn-taking-which has been suggested as an ancient mechanism bridging the existing gap between the articulate human species and their inarticulate primate cousins. However, we know remarkably little about turn-taking systems of non-human animals, and methodological confounds have often prevented meaningful cross-species comparisons. Thus, the extent to which cooperative turn-taking is uniquely human or represents a homologous and/or analogous trait is currently unknown. The present paper draws attention to this promising research avenue by providing an overview of the state of the art of turn-taking in four animal taxa-birds, mammals, insects and anurans. It concludes with a new comparative framework to spur more research into this research domain and to test which elements of the human turn-taking system are shared across species and taxa.Publisher PDFPeer reviewe

Interview with David McLellan July 2018

David McLellan, interviewed here, is a Fellow of Goldsmiths College, University of London and Emeritus Professor of Political Theory, University of Kent. Since the 1970s he has been one of the leading biographers, translators and commentators on Marx in the English-speaking world. He is the author of several books on Marx and Marxism, including The Young Hegelians and Karl Marx; Karl Marx: His Life and Thought; Karl Marx: Selected Writings; Marx before Marxism; and Marxism and Religion. He has also published a biography of Simone Weil, books on the political implications of Christianity, and a lengthy article on contract law and marriage. He lectures widely around the world on these topics, frequently in China, and in 2018 addressed a conference in Nairobi on religion and world peace. In this interview, or conversation, with Larry Ray and Iain Wilkinson, in July 2018, David discusses the origins of his interest in Marx, the development Marx’s thought and his critique of the Hegelians, Marx’s critical method, Marx and religion, Marx on Russia, the role of violence in social change, the relevance of Marx’s work today, and offers comments on some recent biographies. David has spent much of his intellectual career engaging with the meaning and legacy of Marxism and these reflections should generate reflection and debate on the significance of Marx and the possibilities of radical political change today

Interview with David McLellan July 2018

David McLellan, interviewed here, is a Fellow of Goldsmiths College, University of London and Emeritus Professor of Political Theory, University of Kent. Since the 1970s he has been one of the leading biographers, translators and commentators on Marx in the English-speaking world. He is the author of several books on Marx and Marxism, including The Young Hegelians and Karl Marx; Karl Marx: His Life and Thought; Karl Marx: Selected Writings; Marx before Marxism; and Marxism and Religion. He has also published a biography of Simone Weil, books on the political implications of Christianity, and a lengthy article on contract law and marriage. He lectures widely around the world on these topics, frequently in China, and in 2018 addressed a conference in Nairobi on religion and world peace. In this interview, or conversation, with Larry Ray and Iain Wilkinson, in July 2018, David discusses the origins of his interest in Marx, the development Marx’s thought and his critique of the Hegelians, Marx’s critical method, Marx and religion, Marx on Russia, the role of violence in social change, the relevance of Marx’s work today, and offers comments on some recent biographies. David has spent much of his intellectual career engaging with the meaning and legacy of Marxism and these reflections should generate reflection and debate on the significance of Marx and the possibilities of radical political change today

Exploring the conversation of speakers with agrammatic aphasia: some rehabilitative implications

This presentation applies Conversation Analysis (CA) to the phenomenon of agrammatic aphasia. Although mainstream research has done much to characterise the nature of the underlying disorder in agrammatism, most studies have analysed elicited, task-based data by applying the theoretical concepts of a standard grammar. As a result, little is known about the grammar that people with agrammatism use in everyday interaction with habitual conversational partners. There is evidence in the CA literature to suggest that conversational grammar may not mirror the grammar of elicited language samples (Heeschen & Schegloff, 2003). This presentation will investigate the notion that conversation and task-based data do not necessarily reveal the same grammatical phenomena, and will explore the implications for rehabilitation

Infinite Hierarchy of Exact Equations in the Bak-Sneppen Model

We derive an infinite hierarchy of exact equations for the Bak-Sneppen model in arbitrary dimensions. These equations relate different moments of temporal duration and spatial size of avalanches. We prove that the exponents of the BS model are the same above and below the critical point and express the universal amplitude ratio of the avalanche spatial size in terms of the critical exponents. The equations uniquely determine the shape of the scaling function of the avalanche distribution. It is suggested that in the BS model there is only one independent critical exponent.Comment: Submitted to PRL, 4 two-column pages (revtex), 1 ps figure included with epsf, g-zipped, uuencode

The Citizen Nurse: An Educational Innovation for Change

Background: Nursing education needs to provide the necessary tools for students to develop leadership skills and to practice civic agency to create meaningful change in the shifting health care field. This article focuses on facilitating a student\u27s role in becoming a citizen nurse through curricular modifications. Method: Through an ongoing partnership, nursing faculty and community organizers implemented a year-long pilot project to discover the deeper insights into the role of a citizen nurse and to analyze the skills students need to be effective agents of change. Pilot lectures and workshops were held throughout the academic year, and curricular changes were implemented. Results: Based on input from pilot class experiences, student reflections, and faculty workshop feedback, the decision to implement ongoing curricular changes was made by the department. Conclusion: The development of citizen nurses in nursing education will pave the way for praxis embedded in meaningful work with just solutions, enhancing the agency of all involved in promoting health and well-being. [J Nurs Educ. 2017;56(4):247–250.