Flux Density of The Radiative Field At A Measuring Point
There are two main approaches to definition of the spectral flux density at a measuring point in an electromagnetic radiative field. One may be conveniently here labelled the 'vector approach', the other the 'scalar approach'. The vector definition refers to the full spherical integral of the spectral radiance (also known as the specific radiative intensity or specific intensity) at the point, while the scalar definition refers to the many possible hemispheric integrals of the spectral radiance (or specific intensity) at the point. The vector definition seems to be preferred for theoretical investigations of the physics of the radiative field. The scalar definition seems to be preferred for practical applications.
Read more about this topic: Spectral Flux Density
Famous quotes containing the words flux, field, measuring and/or point:
“No civilization ... would ever have been possible without a framework of stability, to provide the wherein for the flux of change. Foremost among the stabilizing factors, more enduring than customs, manners and traditions, are the legal systems that regulate our life in the world and our daily affairs with each other.”
—Hannah Arendt (1906–1975)
“The frequent failure of men to cultivate their capacity for listening has a profound impact on their capacity for parenting, for it is mothers more than fathers who are most likely to still their own voices so they may hear and draw out the voices of their children.”
—Mary Field Belenky (20th century)
“We recognize caste in dogs because we rank ourselves by the familiar dog system, a ladderlike social arrangement wherein one individual outranks all others, the next outranks all but the first, and so on down the hierarchy. But the cat system is more like a wheel, with a high-ranking cat at the hub and the others arranged around the rim, all reluctantly acknowledging the superiority of the despot but not necessarily measuring themselves against one another.”
—Elizabeth Marshall Thomas. “Strong and Sensitive Cats,” Atlantic Monthly (July 1994)
“The realization that he is white in a black country, and respected for it, is the turning point in the expatriate’s career. He can either forget it, or capitalize on it. Most choose the latter.”
—Paul Theroux (b. 1941)