enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Multispectral pattern recognition - Wikipedia

    en.wikipedia.org/wiki/Multispectral_pattern...

    Using the map, the analyst tries to assign or transform the spectral classes into thematic information of interest (i.e. forest, agriculture, urban). This process may not be easy because some spectral clusters represent mixed classes of surface materials and may not be useful. The analyst has to understand the spectral characteristics of the ...

  3. Advanced very-high-resolution radiometer - Wikipedia

    en.wikipedia.org/wiki/Advanced_very-high...

    An image of global sea surface temperatures acquired from the NOAA/ AVHRR satellite. The Advanced Very-High-Resolution Radiometer (AVHRR) instrument is a space-borne sensor that measures the reflectance of the Earth in five spectral bands that are relatively wide by today's standards.

  4. Hyperspectral imaging - Wikipedia

    en.wikipedia.org/wiki/Hyperspectral_imaging

    Top panel: Contour map of the time-averaged spectral radiance at 2078 cm −1 corresponding to a CO 2 emission line. Bottom panel: Contour map of the spectral radiance at 2580 cm −1 corresponding to continuum emission from particulates in the plume. The translucent gray rectangle indicates the position of the stack.

  5. Radiative flux - Wikipedia

    en.wikipedia.org/wiki/Radiative_flux

    Spectral exitance: M e,ν [nb 3] watt per square metre per hertz W⋅m −2 ⋅Hz −1: M⋅T −2: Radiant exitance of a surface per unit frequency or wavelength. The latter is commonly measured in W⋅m −2 ⋅nm −1. "Spectral emittance" is an old term for this quantity. This is sometimes also confusingly called "spectral intensity". M e ...

  6. Multispectral imaging - Wikipedia

    en.wikipedia.org/wiki/Multispectral_imaging

    Multispectral imaging combines two to five spectral imaging bands of relatively large bandwidth into a single optical system. A multispectral system usually provides a combination of visible (0.4 to 0.7 µm), near infrared (NIR; 0.7 to 1 µm), short-wave infrared (SWIR; 1 to 1.7 µm), mid-wave infrared (MWIR; 3.5 to 5 µm) or long-wave infrared ...

  7. Equivalent width - Wikipedia

    en.wikipedia.org/wiki/Equivalent_width

    The photons will be shifted away from the line center, thus rendering the height of the emission line a poor measure of its overall strength. The equivalent width, on the other hand, "measures the fraction of energy removed from the spectrum by the line," regardless of the broadening intrinsic to the line or a detector with poor resolution. [3]

  8. Optical depth - Wikipedia

    en.wikipedia.org/wiki/Optical_depth

    Spectral optical depth or spectral optical thickness is the natural logarithm of the ratio of incident to transmitted spectral radiant power through a material. [1] Optical depth is dimensionless , and in particular is not a length, though it is a monotonically increasing function of optical path length , and approaches zero as the path length ...

  9. Cygnus Loop - Wikipedia

    en.wikipedia.org/wiki/Cygnus_Loop

    A characteristic thermal temperature averaged over the loop from X-ray spectral data is T x = 2.9 ± 1.5 x 10 6 K. [19] An X-ray surface brightness map of the loop was obtained with a one-dimensional X-ray telescope flown aboard an Aerobee 170 sounding rocket launched on March 30, 1973, from the White Sands Missile Range. [19]