7,016 research outputs found

    Rethinking High School: An Introduction to New York City's Experience

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    Provides a review of the small school movement in New York City and highlights the early successes achieved at Marble Hill School for International Studies, located in the Bronx

    Einstein's Equations with Asymptotically Stable Constraint Propagation

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    We introduce a proposal to modify Einstein's equations by embedding them in a larger symmetric hyperbolic system. The additional dynamical variables of the modified system are essentially first integrals of the original constraints. The extended system of equations reproduces the usual dynamics on the constraint surface of general relativity, and therefore naturally includes the solutions to Einstein gravity. The main feature of this extended system is that, at least for a linearized version of it, the constraint surface is an attractor of the time evolution. This feature suggests that this system may be a useful alternative to Einstein's equations when obtaining numerical solutions to full, non-linear gravity.Comment: 23 pages, submitted to JMP, added reference for section

    Workshop on Observations of Recent Comets (1990)

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    Potential interpretations are presented for observations of four comets: Brorsen-Metcalf (1989o), Okazaki-Levy-Rudenko (1989r), Aarseth-Brewington (1989a1), and Austin (1989o1). The relationship of minor species with each other and possible parents as well as with dust are being pursued in a number of investigations. Of particular interest are the abundance ratios of CH4 to CO and NH3 to N2. The need for closer collaboration betwen observing teams and modelers is examined. The need for dust size distribution as a function of cometocentric distance to be analyzed in closer collaboration between observers and modelers is discussed

    Analysis of the effects of baffles on combustion instability

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    An analytical model has been developed for predicting the effects of baffles on combustion instability. This model has been developed by coupling an acoustic analysis of the wave motion within baffled chambers with a model for the oscillatory combustion response of a propellant droplet developed by Heidmann. A computer program was developed for numerical solution of the resultant coupled equations. Diagnostic calculations were made to determine the reasons for the improper prediction. These calculations showed that the chosen method of representing the combustion response was a very poor approximation. At the end of the program, attempts were made to minimize this effect but the model still improperly predicts the stability trends. Therefore, it is recommended that additional analysis be done with an improved approximation

    An Archaeological Assessment (Phase I) of the West Salado Creek Outfall Project, Southeastern Bexar County

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    During August 1988, a cultural resources pedestrian survey was conducted within the West Salado Creek Outfall pipeline easement (two-mile long by 50-foot wide) in southeastern Bexar County, Texas. As a result of surface examination and limited subsurface shovel tests, one prehistoric site (41 BX 785) was recorded. Although some lithic debit age and burned rock fragments were found in the shovel tests at the prehistoric site, there was not enough information from the limited tests to determine if the site is intact. Further testing is recommended to determine if the site is potentially eligible to be nominated to the National Register of Historic Places or to be designated as a State Archeological Landmark

    Bodyspace at the pub: sexual orientations and organizational space

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    In this article we argue that sexuality is not only an undercurrent of service environments, but is integral to the way that these workspaces are experienced and negotiated. Through drawing on Sara Ahmed’s (2006a) ‘orientation’ thesis, we develop a concept of ‘bodyspace’ to suggest that individuals understand, shape and make meaning of work spaces through complex sexually-orientated negotiations. Presenting analysis from a study of UK pubs, we explore bodyspace in the lived experience of workplace sexuality through three elements of orientation: background; bodily dwelling; and lines of directionality. Our findings show how organizational spaces afford or mitigate possibilities for particular bodies, which simultaneously shape expectations and experiences of sexuality at work. Bodyspace therefore provides one way of exposing the connection between sexual ‘orientation’ and the lived experience of service sector work
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