4,457 research outputs found
The Business Model Canvas
Painel do The Business Model generationThe Business Model Canva
Second Symposium on Chemical Evolution and the Origin of Life
Recent findings by NASA Exobiology investigators are reported. Scientific papers are presented in the following areas: cosmic evolution of biogenic compounds, prebiotic evolution (planetary and molecular), early evolution of life (biological and geochemical), evolution of advanced life, solar system exploration, and the Search for Extraterrestrial Intelligence (SETI)
Evaluation and application of the Baldwin-Lomax turbulence model in two-dimensional, unsteady, compressible boundary layers with and without separation in engine inlets
There is a practical need to model high speed flows that exist in jet engine inlets. The boundary layers that form in these inlets may be turbulent or laminar and either separated or attached. Also, unsteady supersonic inlets may be subject to frequent changes in operating conditions. Some changes in the operating conditions of the inlets may include varying the inlet geometry, bleeds and bypasses, and rotating or translating the centerbody. In addition, the inlet may be either started or unstarted. Therefore, a CFD code, used to model these inlets, may have to run for several different cases. Also, since the flow conditions through an unsteady inlet may be continually fluctuating, the CFD code which models these flows may have to be run over many time steps. Therefore, it would be beneficial that the code run quickly. Many turbulence models, however, are cumbersome to implement and require a lot of computer time to run, since they add to the number of differential equations to be solved to model a flow. The Baldwin-Lomax turbulence model is a popular model. It is an algebraic, eddy viscosity model. The Baldwin-Lomax model is used in many CFD codes because it is quick and easy to implement. In this paper, we will discuss implementing the Baldwin-Lomax turbulence model for both steady and unsteady compressible flows. In addition, these flows may be either separated or attached. In order to apply this turbulence model to flows which may be subjected to these conditions, certain modifications should be made to the original Baldwin-Lomax model. We will discuss these modifications and determine whether the Baldwin-Lomax model is a viable turbulence model that produces reasonably accurate results for high speed flows that can be found in engine inlets
Competitive Individualism and the Persistence of Minority Disadvantage
http://deepblue.lib.umich.edu/bitstream/2027.42/51088/1/320.pd
BOSQUE, Ignacio, ed. (2006): Diccionario combinatorio práctico del español contemporáneo [Reseña]
[Resumen] Reseña de Bosque, Ignacio, ed. (2006): Diccionario combinatorio práctico del español contemporáneo, Madrid, SM
Finite temperature effects on the antikaon optical potential
By solving the Bethe-Goldstone equation, we have obtained the
optical potential from the effective interaction in nuclear matter
at T=0. We have extended the model by incorporating finite temperature effects
in order to adapt our calculations to the experimental conditions in heavy-ion
collisions. In the rank of densities (), the finite temperature
optical potential shows a smooth behaviour if we compare it to the
T=0 outcome. Our model has also been applied to the study of the ratio between
and produced at GSI with around 70 MeV. Our results point at
the necessity of introducing an attractive optical potential.Comment: 7 pages, 4 figures. Contribution to the proceedings of Mesons & Light
Nuclei '01 (2-6th July, Prague
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