Koschmieder equation

A proper control strategy for visibility protection at a given location requires information about the relationship between each source and its contribution to a quantity called the extinction coefficient, bg. The visual range, Vj, and bg are related through the Koschmieder equation (1 ). 

The Koschmieder equation has been shown to approximate the change in contrast of an object with distance away from an observer (Middleton, 1952) note that it has a form similar to that of the Beer-Lambert law ... 

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