1,349 research outputs found
Cosmic censorship of smooth structures
It is observed that on many 4-manifolds there is a unique smooth structure
underlying a globally hyperbolic Lorentz metric. For instance, every
contractible smooth 4-manifold admitting a globally hyperbolic Lorentz metric
is diffeomorphic to the standard . Similarly, a smooth 4-manifold
homeomorphic to the product of a closed oriented 3-manifold and and
admitting a globally hyperbolic Lorentz metric is in fact diffeomorphic to
. Thus one may speak of a censorship imposed by the global
hyperbolicty assumption on the possible smooth structures on
-dimensional spacetimes.Comment: 5 pages; V.2 - title changed, minor edits, references adde
The hornich topology for schlicht functions
In this work the results of Hornich and some of the results of Cima and Pfaltzgraff are presented. These results are primarily concerned with the characterization of the interior of the closed set S, with connectivity of schlicht and of non-schlicht funtions, and with the local structure of the space H
A study of prediction methods for the high angle-of-attack aerodynamics of straight wings and fighter aircraft
Work is described dealing with two areas which are dominated by the nonlinear effects of vortex flows. The first area concerns the stall/spin characteristics of a general aviation wing with a modified leading edge. The second area concerns the high-angle-of-attack characteristics of high performance military aircraft. For each area, the governing phenomena are described as identified with the aid of existing experimental data. Existing analytical methods are reviewed, and the most promising method for each area used to perform some preliminary calculations. Based on these results, the strengths and weaknesses of the methods are defined, and research programs recommended to improve the methods as a result of better understanding of the flow mechanisms involved
Evaluation of LANDSAT-2 data for selected hydrologic applications
There are no author-identified significant results in this report
The National COPD Audit – what you need to know
The secondary care work stream of the National COPD Audit Programme aims to improve care and outcomes for patients with exacerbation of chronic obstructive pulmonary disease (COPD) wherever and whenever they are admitted to hospital. To achieve this, prospective audit is combined with real-time feedback of data to individual units, together with support for quality improvement and high-level change levers. COPD exacerbations comprise a large proportion of the acute take. Only by working collaboratively across emergency, acute and general medicine, respiratory, geriatric and other teams can individual trusts deliver optimal care. This review provides background to the national COPD audit programme, relevant to all those caring for people with COPD exacerbations in secondary care
Evaluation of LANDSAT-2 data for selected hydrologic applications
There are no author-identified significant results in this report
Short Range Ising Spin Glasses: a critical exponent study
The critical properties of short-range Ising spin-glass models, defined on a
diamond hierarchical lattice of graph fractal dimension , 3, and 4,
and scaling factor 2 are studied via a method based on the Migdal-Kadanoff
renormalization-group scheme. The order parameter critical exponent is
directly estimated from the data of the local Edwards- Anderson (EA) order
parameter, obtained through an exact recursion procedure. The scaling of the EA
order parameter, leading to estimates of the exponent of the correlation
length is also performed. Four distinct initial distributions of the quenched
coupling constants (Gaussian, bimodal, uniform and exponential) are considered.
Deviations from a universal behaviour are observed and analysed in the
framework of the renormalized flow in a two dimensional appropriate parameter
space.Comment: 9 pages, 01 figure (ps
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