Lighting a particular area, and falls within a given solid angle. The SI unit for luminance is candela per square metre (cd/m). The CGS unit of luminance is the stilb, which is equal to one candela per square centimetre or 10 kcd/m. The amount of useful light emitted from a source or the luminous flux is measured in lumen (lm). The SI unit of illuminance and luminous emittance, being the luminous power per area, is measured in Lux. It is used in photometry as a measure of the intensity, as perceived by the human eye, of light that hits or passes
Rose is a rose is a rose is a rose In Stein's view, the sentence expresses the fact that simply using the name of a thing already invokes the imagery and emotions associated with it, an idea also intensively discussed in the problem of universals debate where Peter Abelard and others used the "rose" as an example concept. As the quotation diffused through her own writing, and the culture at large, Stein once remarked, "Now listen! I'm no fool. I know that in daily life we don't go around saying 'is a ... is a ... is a ...' Yes, I'm no fool; but I think that in that line