Error analysis of velocity and direction measurements of plane waves using thick large‐aperture arrays

1973 ◽  
Vol 53 (4) ◽  
pp. 1161-1166 ◽  
Author(s):  
C. S. Clay ◽  
M. J. Hinich ◽  
P. Shaman
Keyword(s):  
Error Analysis ◽  
Plane Waves ◽  
Large Aperture ◽  
Aperture Arrays

Flat-stitching error analysis of large-aperture photon sieves

2013 ◽  
Vol 53 (1) ◽  
pp. 90 ◽  
Author(s):  
Guang Jin ◽  
Junliang Yan ◽  
Hua Liu ◽  
Xing Zhong ◽  
Yong Yan
Keyword(s):  
Error Analysis ◽  
Large Aperture ◽  
Photon Sieves

System Architecture Of Mmic-Based Large Aperture Arrays For Space Applications

1987 ◽  
Author(s):  
P. R. Herczfeld ◽  
M. Kam ◽  
R. R. Kunath ◽  
K. B. Bhasin ◽  
Nick L. Prade
Keyword(s):  
System Architecture ◽  
Space Applications ◽  
Large Aperture ◽  
Aperture Arrays

scholarly journals Sensitivity of large-aperture scintillometer measurements of area-average heat fluxes to uncertainties in topographic heights

2014 ◽  
Vol 7 (1) ◽  
pp. 33-68
Author(s):  
M. A. Gruber ◽  
G. J. Fochesatto ◽  
O. K. Hartogensis
Keyword(s):  
Error Analysis ◽  
Sensitivity Function ◽  
Heat Fluxes ◽  
Index Structure ◽  
Real Field ◽  
Computational Error ◽  
One Dimensional ◽  
Coupled Equations ◽  
Large Aperture ◽  
Beam Height

Abstract. Scintillometer measurements allow for estimations of the refractive index structure parameter Cn2 over large areas in the atmospheric surface layer. Turbulent fluxes of heat and momentum are inferred through coupled sets of equations derived from the Monin–Obukhov similarity hypothesis. One-dimensional sensitivity functions have been produced that relate the sensitivity of heat fluxes to uncertainties in single values of beam height over homogeneous and flat terrain. However, real field sites include variable topography and heterogeneous surfaces. We develop here the first analysis of the sensitivity of scintillometer derived sensible heat fluxes to uncertainties in spatially distributed topographic measurements. For large-aperture scintillometers and independent friction velocity u* measurements, sensitivity is shown to be concentrated in areas near the center of the beam path and where the underlying topography is closest to the beam height. Uncertainty may be greatly reduced by focusing precise topographic measurements in these areas. A new two-dimensional variable terrain sensitivity function is developed for quantitative error analysis. This function is compared with the previous one-dimensional sensitivity function for the same measurement strategy over flat and homogeneous terrain. Additionally, a new method of solution to the set of coupled equations is produced that eliminates computational error. The results are produced using a new methodology for error analysis involving distributed parameters that may be applied in other disciplines.

Used in Acoustic Projects Calculation of Reflection Coefficient for End Opening of Channel without Flange

2017 ◽  
Vol 6 (3) ◽  
pp. 34-41
Author(s):  
Владимир Тупов ◽  
Vladimir Tupov ◽  
А. Миронова ◽  
A. Mironova
Keyword(s):  
Reflection Coefficient ◽  
Error Analysis ◽  
Plane Waves ◽  
Computational Error ◽  
Sound Waves ◽  
Computer Approach ◽  
Coefficient Of Reflection ◽  
Plane Sound ◽  
Opening Channel

The computational error analysis for coefficient of reflection of plane sound waves at the end of opening channel without flange performed by means of formulas commonly used in practice has demonstrated their unacceptability for accurate acoustic calculations, and limitations of the Helmholtz numbers’ range, where these formulas are applicable. In this work have been proposed calculated dependences, convenient for practical usage and enabling more accurately calculate by computer approach the considered quantity’s values in a whole range of existence of the plane waves in the channel.

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