1,668 research outputs found

    High Specification Offshore Blades: Work Package: 1B: Blades Design

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    This report outlines the current state of the art in offshore wind turbine blade aerodynamic design, along with the key technical limitations and possible technologies which may improve the aerodynamic design of blades and turbine rotors in the future. It is suggested that there are three principal areas in which aerodynamic improvements can be made to the design of offshore wind turbine systems: improved rotor system and blade tip design for operation at higher tip speeds, optimisation of wind farm design to alleviate aerodynamic interactions between individual turbines, and the aerodynamic feasibility of using structural mode coupling to achieve pitch and/or stall control of the loads on blades

    Parental influences on high school student achievement and goals

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    The present study examined parental influences on educational and career goals of high school students. Data on educational and career goals from the Perceived Life Chances Interview were derived from 124 rural adolescents. One hundred of their mothers and 36 of their fathers completed the Inventory of Parental Influence which consists of five subscales of Parental Involvement/Help, Psychological Support, Parental Pressure, Pressure for Intellectual Development, and Time Management/Monitoring. Responses from the Perceived Life Chances Interview were qualitatively analyzed in order to derive categories that reflected the varying responses from participants. These categories served as dependent variables in a series of discriminant function and regression analyses that included the five subscales of the Inventory of Parental Influence, race, and gender as the predictor variables. It was evident from present and prior research that parental influences were found to be associated with adolescent achievement and career goals

    Hyperbolicity and Constrained Evolution in Linearized Gravity

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    Solving the 4-d Einstein equations as evolution in time requires solving equations of two types: the four elliptic initial data (constraint) equations, followed by the six second order evolution equations. Analytically the constraint equations remain solved under the action of the evolution, and one approach is to simply monitor them ({\it unconstrained} evolution). Since computational solution of differential equations introduces almost inevitable errors, it is clearly "more correct" to introduce a scheme which actively maintains the constraints by solution ({\it constrained} evolution). This has shown promise in computational settings, but the analysis of the resulting mixed elliptic hyperbolic method has not been completely carried out. We present such an analysis for one method of constrained evolution, applied to a simple vacuum system, linearized gravitational waves. We begin with a study of the hyperbolicity of the unconstrained Einstein equations. (Because the study of hyperbolicity deals only with the highest derivative order in the equations, linearization loses no essential details.) We then give explicit analytical construction of the effect of initial data setting and constrained evolution for linearized gravitational waves. While this is clearly a toy model with regard to constrained evolution, certain interesting features are found which have relevance to the full nonlinear Einstein equations.Comment: 18 page

    The effect of color in the Rorschach test and in selected intellectual tasks.

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    Thesis (Ph.D.)--Boston UniversityAn important theoretical basis of the Rorschach test is the assumption that the subject's reactions to specific stimulus qualities of the ink blots, such as form and color, relate to specific personality variables. Our verified knowledge of the function of these various stimuli in perception has been limited. This may be due partly to the adequacy of validation studies which focus on overall interpretations of test results and partly to experimental difficulties in dealing with single variables out of their complex context. The purpose of this study was to provide an experimental examination of the influence of color in the Rorschach test and in independent performance tasks. [TRUNCATED

    Review of \u3cem\u3eThe Fukushima Dai-Ichi Accident\u3c/em\u3e. Peter Bernard Ladkin, Christoph Goeker, and Bernd Sieker (Eds.). Reviewed by Richard York

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    Peter Bernard Ladkin, Christoph Goeker, and Bernd Sieker (Eds.), The Fukushima Dai-Ichi Accident. Lit Verlag (2013). $59.95 (paperback), 291 pages

    A search for 'creative' 'partnerships' : constructing pedagogies for artists and educators working together

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    This thesis examines what constitutes a 'creative' 'partnership' and whether theoretical frameworks and models can be articulated which produce 'creative partnerships'. The thesis derives from an ethnographic study of Fichte Nursery School and artists and educators working within Creative Partnerships programmes in Hull, based upon qualitative research and narrative enquiry.The thesis presents an historical perspective of creativity and cultural education in English schools and suggests that, as a result of performativity discourses within education, contemporary discourses of creativity are determined by social relationships based in Gesellschaft as opposed to Gemeinschaft, and are heavily prescribed by political agendas which strive for economic growth and thus become supersaturated with meaning and desire.A Deleuzian philosophy of creativity is proposed as a suitable philosophical basis for this research, as the concept of heterogenesis allows for the possibility of the development of an alternative discourse of creativity in which social relationships are more closely aligned to conditions of gemeinschaft.The thesis identifies discourses upon which pedagogies for artists and educators might be established and argues that pedagogies are ambiguous and contingent architextures which define learning spaces. The Nursery School is seen as an example of a complex, heterogenetic Deleuzian city and it is presented as the site for the empirical research. The thesis examines the manifestation of creativity in the school, the manifestation of creativity by artists in schools and the role of 'outsiders' in participating in creative relationships.Six structural features are presented which form the architexture of the pedagogies of artists and educators, conceived as six interconnected Zones: a Zone of Scrap, of Disguise, of Infectivity, of Intimacy, of Surprise and a Zone of Grace. A new methodological tool is proposed, to observe classroom practice: that of the Classroom Gaze. Implications for policy, practice and practitioners are discussed

    Super-Extremal Spinning Black Holes via Accretion

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    A Kerr black hole with mass MM and angular momentum JJ satisfies the extremality inequality ∣J∣≤M2|J| \le M^2. In the presence of matter and/or gravitational radiation, this bound needs to be reformulated in terms of local measurements of the mass and the angular momentum directly associated with the black hole. The isolated and dynamical horizon framework provides such quasi-local characterization of black hole mass and angular momentum. With this framework, it is possible in axisymmetry to reformulate the extremality limit as ∣J∣≤2 MH2|J| \le 2\,M_H^2, with MHM_H the irreducible mass of the black hole computed from its apparent horizon area and JJ obtained using approximate rotational Killing vectors on the apparent horizon. The ∣J∣≤2 MH2|J| \le 2\,M_H^2 condition is also equivalent to requiring a non-negative black hole surface gravity. We present numerical experiments of an accreting black hole that temporarily violates this extremality inequality. The initial configuration consists of a single, rotating black hole surrounded by a thick, shell cloud of negative energy density. For these numerical experiments, we introduce a new matter-without-matter evolution method.Comment: 11 pages, 10 figure

    Potential Legal Facilitation or Impediment of Wind Energy Conversion System Siting

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    The purpose of this article is to broadly identify competing interests at stake in wind energy conversion systems (WECS) development and the potential constraints of local, state, and federal regulation and common law principles on the siting of WECS. First, the article addresses common law and regulatory means of facilitating wind energy development by protecting the WECS developer\u27s interest in unobstructed wind flow. Second, it examines the potential restriction of WECS development by common law and regulatory responses to the demands of neighbors and the general public whose interests may be detrimentally affected by wind turbine operation
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