Wavenumber Wavenumber In the physical sciences, the wavenumber (also wave number or repetency) is the spatial frequency of a wave, measured in cycles per unit distance or radians per unit distance. Whereas temporal frequency can be thought of as the number of waves per unit time, wavenumber is the number of waves per unit distance. In multidimensional systems, the wavenumber is the magnitude of the wave vector. The space of wave vectors is called reciprocal space. Wave numbers and wave vectors play an essential role in optics and the physics of wave scattering, such as X-ray diffraction, neutron diffraction, and elementary
Material input per service unit (MI) of the product can be reduced or amount of service units (S) can be increased. Material input in the production phase can be reduced by using less energy or raw materials. Also transport chains can be rationalized. In the use phase the material input per unit of service can be reduced when amount of service produced is increased. For instance in case of a newspaper the material input can be reduced by using recycled paper instead of primary. Material input per reader decreases when the same paper is shared with several persons. High quality products and availability of spares