Nyquist frequency signal, whereas "Nyquist frequency" is a property of a discrete-time system. When the function domain is time, sample rates are usually expressed in samples per second, and the unit of Nyquist frequency is cycles per second (hertz). When the function domain is distance, as in an image sampling system, the sample rate might be dots per inch and the corresponding Nyquist frequency would be in cycles/inch. Referring again to Figure 1, undersampling of the sinusoid at 0.6 f is what allows there to be a lower-frequency "alias", which is a different function that produces the same set of samples. That
Edible protein per unit area of land usable protein per unit area than any other major vegetable or grain crop, except for hemp which can produce up to . They produce 5 to 10 times more protein per unit area than land set aside for grazing animals to make milk, and up to 15 times more protein per unit area than land set aside for meat production. Selected averages as computed in the 1970s. Edible protein per unit area of land Edible protein per unit area of land is a measure of agricultural productivity. This measure for various major foodstuffs is shown in the chart below. Values