By definition, the CFFF is "the highest or lowest temporal frequency, at a given percentage modulation, that can be resolved." (Schwartz, Visual Perception, 3rd ed.) In other words, the limits of distinguishing a flashing light from a steady one (at both the slow and fast end limits). Percentage modulation is calculated using the amplitude of the luminance of the light source, and the time-averaged luminance of said light source. In other words, the difference between the brightest/dimmest points in the cycle, averaged over the speed it takes to vary between the two points. Percentage modulation is used to calculate Relative Sensitivity, which is (1 / Percentage Modulation). For example: A lightbulb powered by Alternating Current (AC) is flickering. This is not visible to the normal human eye for two reasons (both variables in the definition of CFFF.) The temporal frequency of the AC in most American homes is 60Hz. The high temporal frequency cut-off for human sensitivity varies, and some cells are known to be sensitive to frequencies as high as 250 Hz, but for general daytime vision, it is lower than 60Hz. Also, the percentage modulation of a light bulb is low, since the change in brightness of the filament is very small. Relative sensitivity is the inverse of the percentage modulation. For flicker to be visible, a light source must have a relatively large change in level of brightness, and flicker at a rate within the human sensitivity range, somewhere between 2 and 50Hz. By definition, the CFFF is "the highest or lowest temporal frequency, at a given percentage modulation, that can be resolved." (Schwartz, Visual Perception, 3rd ed.) In other words, the limits of distinguishing a flashing light from a steady one (at both the slow and fast end limits). Percentage modulation is calculated using the amplitude of the luminance of the light source, and the time-averaged luminance of said light source. In other words, the difference between the brightest/dimmest points in the cycle, averaged over the speed it takes to vary between the two points. Percentage modulation is used to calculate Relative Sensitivity, which is (1 / Percentage Modulation). For example: A lightbulb powered by Alternating Current (AC) is flickering. This is not visible to the normal human eye for two reasons (both variables in the definition of CFFF.) The temporal frequency of the AC in most American homes is 60Hz. The high temporal frequency cut-off for human sensitivity varies, and some cells are known to be sensitive to frequencies as high as 250 Hz, but for general daytime vision, it is lower than 60Hz. Also, the percentage modulation of a light bulb is low, since the change in brightness of the filament is very small. Relative sensitivity is the inverse of the percentage modulation. For flicker to be visible, a light source must have a relatively large change in level of brightness, and flicker at a rate within the human sensitivity range, somewhere between 2 and 50Hz.
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∙ 2009-04-19 22:32:56The fusion frequency is the minimum stimulus required to elicit tetanus in a muscle. For example, the fusion frequency can be given in terms of volts (V), or it can be given in terms of whatever units by which the applied stimuli are being measured.
For nuclear fission reactors there is no critical temperature, though they do have a temperature coefficient which makes the efficiency of the chain reaction vary slightly with temperature. This can be negative or positive, obvously a negative coefficient is preferred and is safer. Nuclear fusion is another matter, and very high temperatures are required in tokamaks to get fusion started
This is generally referred to as Bubble fusion, or sonofusion. No repeatable and independently verified test has proved that this is possible and sustainable. ----
Fusion is a type of
Fungi reproduction
A quck test that differtiates those under great stress from more normal people is the CFF (critical frequency fusion).
Critical speed means where natural frequency is equal to system frequency.
The fusion frequency is the minimum stimulus required to elicit tetanus in a muscle. For example, the fusion frequency can be given in terms of volts (V), or it can be given in terms of whatever units by which the applied stimuli are being measured.
For satllite communication the frequency should not be less than the critical frequency because in satellite communicaton high frequency is needed which is reflected by satellite but not by the ionosphere.
Vernon Lemont Miller has written: 'The critical frequency limen for visual flicker in children between the ages of 6 and 18' -- subject(s): Left- and right-handedness, Physiological optics, Vision
Walter Philip Weisenburger has written: 'The effects on diazepam on the critical flicker frequency (CFF) of pigtail monkeys (Macaca nemestrina)' -- subject(s): Physiological effect, Diazepam, Visual perception, Light
about 10500-11000k is when fusion commences which creates the shining of the star
The anti flicker in the 50Hz and 60Hz helps to compensate for the frequency of the electrical supply.
About 10,000,000K.
flare, fusion, falling star, frequency
I suppose the formula is: MUF=critical frequency/cosine(angle of incidence). ex:The MUF for an angle of incidence of 60 deg and a critical frequency of 60MHz will be MUF=60 * 10^6/cos(60) =120 MHz By VSR
Fusion. Fusion requires very high temperature and pressure. So on earth we usea critical mass of weapons grade uranium to start a fission chain reaction whichenables a fusion reaction in hydrogen. Fusion is of course more powerful than fission