11,521 research outputs found
On Nilcompactifications of Prime Spectra of Commutative Rings
Given a ring R and S one of its ideals, we obtain a compactification of the
prime spectrum of S through a mainly algebraic process. We name it the
R-nilcompactification of SpecS. We study some categorical properties of this
construction.Comment: 12 pages, 8 Tikz figure
Imaging Fourier Transform Spectroscopy of the Boundary Layer Plume from Laser Irradiated Polymers and Carbon Materials
Emissive plumes from laser irradiated fiberglass reinforced polymers (FRP), poly(methyl methacrylate) (PMMA) and porous graphite targets were investigated primarily using a mid wave infrared (MWIR) imaging Fourier transform infrared (FTIR) spectrometer. Polymer and graphite targets were irradiated with a 1.064 micrometer Nd:YAG and a 1.07 micrometer ytterbium continuous wave (CW) fiber lasers respectively. Data was acquired with a spectral resolution of 2 cm-1 and spatial resolution as high as 0.52 mm2 per pixel. Strong emissions from H2O, CO, CO2 and hydrocarbons were observed in the MWIR between 1900 cm-1 and 4000 cm- 1. A single-layer radiative transfer model was developed to estimate spatial maps of temperature and column densities of CO and CO2 from the hyperspectral imagery of the boundary layer plume of irradiated FRP and porous graphite targets. The spectral model was used to compute the absorption cross sections of CO and CO2 using spectral line parameters from the high temperature extension of the HITRAN. Also, spatial maps of plume temperature and methyl methacrylate (MMA) column density were developed for laser irradiated black PMMA
Characterization of Lift and Drag on Two Dimensional Airfoils with and without Sinusoidal Leading Edges
An experimental investigation was taken on a 63-021 NACA airfoil, to characterize lift and drag and how the effects of sinusoidal leading edges affect the aerodynamic properties. A theoretical model is also purposed by implementing a perturbation on thin-airfoil theory.
Two sets of airfoils were machined and tested inside a low-speed open circuit wind tunnel. Data from a pressure scanner and particle image velocity will give an insight of how the modified leading edges affect the aerodynamic properties. A Fourier series expansion was used to solve for the lifting-line model, by use of thin-airfoil theory and complex number theory
Impact pathway analysis for research planning: the case of aquatic resources research in the WorldFish Center
In line with its mandate of poverty reduction and sustainable development, the WorldFish Center is orienting its research towards high impact scientific activity. Identifying such activities is the task of prospective impact assessment, in turn based on impact pathway analysis. The paper describes a framework for analyzing benefits from aquatic resources research, the relevant research categories, pathways to impact by category, and indicators along each pathway that can be estimated in order to quantify probable research impact
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