11,231 research outputs found
Properties of various silicon oxide phases in thin films
Layers of SiO2 with reproducible properties can be manufactured relatively easily today. In the case of SiO and Si2O3 layers, it is necessary to carefully check all of the manufacturing parameters for producing layers with reproducible properties. The properties of the layers in the case of SiO2 do conform to expectations. In the case of Si2O3 and SiO, they can be understood at least qualitatively. Additional interesting models are available for a quantitative understanding
A proof-theoretic analysis of the classical propositional matrix method
The matrix method, due to Bibel and Andrews, is a proof procedure designed for automated theorem-proving. We show that underlying this method is a fully structured combinatorial model of conventional classical proof theory. © 2012 The Author, 2012. Published by Oxford University Press
A fast and portable Re-Implementation of Piskunov and Valenti's Optimal-Extraction Algorithm with improved Cosmic-Ray Removal and Optimal Sky Subtraction
We present a fast and portable re-implementation of Piskunov and Valenti's
optimal-extraction algorithm (Piskunov & Valenti, 2002} in C/C++ together with
full uncertainty propagation, improved cosmic-ray removal, and an optimal
background-subtraction algorithm. This re-implementation can be used with IRAF
and most existing data-reduction packages and leads to signal-to-noise ratios
close to the Poisson limit. The algorithm is very stable, operates on spectra
from a wide range of instruments (slit spectra and fibre feeds), and has been
extensively tested for VLT/UVES, ESO/CES, ESO/FEROS, NTT/EMMI, NOT/ALFOSC,
STELLA/SES, SSO/WiFeS, and finally, P60/SEDM-IFU data.Comment: 23 pages, 12 figure
Effect of the NACA Injection Impeller on the Mixture Distribution of a Double-Row Radial Aircraft Engine
The NACA injection impeller was developed to improve the mixture distribution of aircraft engines by discharging the fuel from a centrifugal supercharger impeller, thus promoting a thorough mixing of fuel and charge air. Tests with a double-row radial aircraft engine indicated that for the normal range of engine power the NACA injection impeller provided marked improvement in mixture distribution over the standard spray-bar injection system used in the same engine. The mixture distribution at cruising conditions was excellent; at 1200, 15OO, and 1700 brake horsepower, the differences between the fuel-air ratios of the richest and the leanest cylinders were reduced to approximately one-third their former values. The maximum cylinder temperatures were reduced about 30 [degrees] F and the temperature distribution was improved by approximately the
degree expected from the improvement in mixture distribution. Because the mixture distribution of the engine tested improves slightly at engine powers exceeding 1500 brake horsepower and because the effectiveness of the particular impeller diminished slightly at high rates of fuel flow, the improvement in mixture distribution at
rated power and rich mixtures was less than that for other conditions.
The difference between the fuel-air ratios of the richest and the leanest cylinders of the engine using the standard spray bar was so great that the fuel-air ratios of several cylinders were well below the chemically correct mixture, whereas other cylinders were operating at rich mixtures. Consequently, enrichment to improve engine cooling actually increascd some of the critical temperatures. The uniform mixture distribution providod by the injection impeller restored the normal response of cylinder temperatures to mixture enrichnent
An analytical model for bore-driven run-up
We use a hodograph transformation and a boundary integral method to derive a new analytical solution to the shallow-water equations describing bore-generated run-up on a plane beach. This analytical solution differs from the classical Shen-Meyer runup solution in giving significantly deeper and less asymmetric swash flows, and also by predicting the inception of a secondary bore in both the backwash and the uprush in long surf. We suggest that this solution provides a significantly improved model for flows including swash events and the run-up following breaking tsunamis
Place-Based Chaplaincy: An Interfaith Approach to Chaplaincy Training.
M.A. Thesis. University of Hawaiʻi at Mānoa 2018
Investigation of topographical stability of the concave and convex Self-Organizing Map variant
We investigate, by a systematic numerical study, the parameter dependence of
the stability of the Kohonen Self-Organizing Map and the Zheng and Greenleaf
concave and convex learning with respect to different input distributions,
input and output dimensions
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