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The structural cut-off is a concept in network science which imposes a degree cut-off in the degree distribution of a finite size network due to structural limitations (such as the simple graph property). Networks with vertices with degree higher than the structural cut-off will display structural disassortativity.
where is the wavelength expressed in millimeters and F # is the lens' focal ratio. As an example, a telescope having an f /6 objective and imaging at 0.55 micrometers has a spatial cutoff frequency of 303 cycles/millimeter. High-resolution black-and-white film is capable of resolving details on the film as small as 3 micrometers or smaller ...
As a voltage ratio this is a fall to / of the passband voltage. [1] Other ratios besides the 3 dB point may also be relevant, for example see § Chebyshev filters below. Far from the cutoff frequency in the transition band, the rate of increase of attenuation ( roll-off ) with logarithm of frequency is asymptotic to a constant.
Percent bandwidth is a less meaningful measure in wideband applications. A percent bandwidth of 100% corresponds to a ratio bandwidth of 3:1. All higher ratios up to infinity are compressed into the range 100–200%. Ratio bandwidth is often expressed in octaves (i.e., as a frequency level) for wideband applications.
Alpha cutoff frequency, or is the frequency at which the common base DC current gain drops to 0.707 of its low frequency value. The common base DC current gain is the ratio of a transistor's collector current to the transistor's emitter current , or α = i C i E {\displaystyle \alpha ={\frac {i_{C}}{i_{E}}}} .
Roll-off enables the cut-off performance of such a filter network to be reduced to a single number. Note that roll-off can occur with decreasing frequency as well as increasing frequency, depending on the bandform of the filter being considered: for instance a low-pass filter will roll-off with increasing frequency, but a high-pass filter or ...
The bandwidth is defined as = and since the lower cutoff frequency f L is usually several decades lower than the higher cutoff frequency f H, All systems analyzed here have a frequency response which extends to 0 (low-pass systems), thus f L = 0 f H = B W {\displaystyle f_{L}=0\,\Longleftrightarrow \,f_{H}=BW} exactly.
In electronics, cut-off is a state of negligible conduction that is a property of several types of electronic components when a control parameter (that usually is a well-defined voltage or electric current, but could also be an incident light intensity or a magnetic field), is lowered or increased past a value (the conduction threshold).