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The ratio of the measured antenna temperature change during a drift scan across the moon to the average brightness temperature of the moon over the antenna beam ( assuming that the brightness temperature of the sky is negligible ) was found, by graphical integration of the antenna directivity diagram, to be 0.85.
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ratio and measured
The electric charge-to-mass ratio of a particle can be measured by observing the radius of curling of its cloud-chamber track in a magnetic field.
The depth of water is necessary for determining scope, which is the ratio of length of cable to the depth measured from the highest point ( usually the anchor roller or bow chock ) to the seabed.
The radiation flux without a sample and with a sample in the atomizer is measured using a detector, and the ratio between the two values ( the absorbance ) is converted to analyte concentration or mass using the Beer-Lambert Law.
The gain of an amplifier is the ratio of output to input power or amplitude, and is usually measured in decibels.
( When measured in decibels it is logarithmically related to the power ratio: G ( dB )= 10 log ( P < sub > out </ sub > /( P < sub > in </ sub >)).
In general, smaller animals tend to have larger brains, measured as a fraction of body size: the animal with the largest brain-size-to-body-size ratio is the hummingbird.
However, before reaching the transition temperature, the specific heat of the superconductor becomes even higher than that of the normal conductor ( measured immediately above the transition ) and the ratio of these two values is found to be universally given by 2. 5.
* Viewable image size is usually measured diagonally, but the actual widths and heights are more informative since they are not affected by the aspect ratio in the same way.
This ratio of large HDL to total HDL particles varies widely and is measured only by more sophisticated lipoprotein assays using either electrophoresis ( the original method developed in the 1970s ) or newer NMR spectroscopy methods ( See also: NMR and spectroscopy ), developed in the 1990s.
Underwriting performance is measured by something called the " combined ratio " which is the ratio of expenses / losses to premiums.
The term now applies to any signal that can be measured or decomposed along a continuous variable such as energy in electron spectroscopy or mass to charge ratio in mass spectrometry.
Thus, by measuring the current-day < sup > 87 </ sup > Sr /< sup > 86 </ sup > Sr ratio ( and often the Nd-Nd ratios as well ) the geological fingerprint of an object or skeleton can be measured, allowing migration patterns to be determined.
It is measured as the lowest ratio of the power of two signals that will result in the suppression of the smaller signal.
dBm ( sometimes dBmW ) is an abbreviation for the power ratio in decibels ( dB ) of the measured power referenced to one milliwatt ( mW ).
The degree of isochronous distortion, in data transmission, is the ratio of the absolute value of the maximum measured difference between the actual and the theoretical intervals separating any two significant instants of modulation ( or demodulation ), to the unit interval.
# In asynchronous data transmission, the ratio of ( a ) the absolute value of the maximum measured difference between the actual and theoretical intervals separating any significant instant of modulation ( or demodulation ) from the significant instant of the start element immediately preceding it to ( b ) the unit interval.
It is measured as a ratio, or as a base-10 ( decibel ) or base-2 ( doublings, bits or stops ) logarithmic value.
When the image rejection ratio is measured, the input signal levels of the desired and image frequencies must be equal for the measurement to be meaningful.
In acoustics, the sound pressure of a spherical wavefront radiating from a point source decreases by 50 % as the distance r is doubled ; measured in dB, the decrease is still 6. 02 dB, since dB represents an intensity ratio.
Important examples include: the damping ratio, relative bandwidth, linewidth and bandwidth measured in octaves.
If the signal and the noise are measured across the same impedance, then the SNR can be obtained by calculating the square of the amplitude ratio:
It is usually measured by inputting a sine wave, notch filtering the output, and comparing the ratio between the output signal with and without the sine wave:
It is measured in traffic units ( erlangs ) and defined as the ratio of the time during which a facility is cumulatively occupied to the time this facility is available for occupancy.
ratio and antenna
Note 1: Aperture-to-medium coupling loss is related to the ratio of the scatter angle to the antenna beamwidth.
However, the drawback of this small focal ratio is that the antenna has a small field of view, the angular width that it can effectively focus.
Sometimes this results in the counterintuitive finding that reducing the height of an antenna increases the signal-to-noise ratio.
# The ratio of power gain between the front and rear of a directional antenna.
For receiving antennas, the ratio of received-signal strength when the antenna is rotated 180 °.
The ratio compares the antenna gain in a specified direction, i. e., azimuth, usually that of maximum gain, to the gain in a direction 180 ° from the specified azimuth.
In point-to-point microwave antennas, a " high performance " antenna usually has a higher front to back ratio than other antennas.
Other factors affecting the front to back ratio of a parabolic microwave antenna include the material of the dish and the precision with which the reflector itself was formed.
This makes the noise figure a useful figure of merit for terrestrial systems where the antenna effective temperature is usually near the standard 290 K. In this case, one receiver with a noise figure say 2 dB better than another, will have an output signal to noise ratio that is about 2 dB better than the other.
However, in the case of satellite communications systems, where the antenna is pointed out into cold space, the antenna effective temperature is often colder than 290 K. In these cases a 2 dB improvement in receiver noise figure will result in more than a 2 dB improvement in the output signal to noise ratio.
Impedance matching is important when components of an electric circuit are connected ( waveguide to antenna for example ): The impedance ratio determines how much of the wave is transmitted forward and how much is reflected.
In antenna design, antenna gain is the ratio of power received by a directional antenna to power received by an isotropic antenna.
Antenna gain is usually defined as the ratio of the power produced by the antenna from a far-field source on the antenna's beam axis to the power produced by a hypothetical lossless isotropic antenna, which is equally sensitive to signals from all directions.
The directive gain signifies the ratio of radiated power in a given direction relative to that of an isotropic radiator which is radiating the same total power as the antenna in question but uniformly in all directions.
The power gain, on the other hand, signifies the ratio of radiated power in a given direction relative to that of an isotropic radiator which is radiating the total amount of electrical power received by the antenna in question.
That ratio would be equal to G if the reference antenna were an isotropic radiator.
To do this efficiently one would require remotely adjusting a matching network at the site of the antenna, since simply adjusting a matching network at the transmitter ( or receiver ) would leave the transmission line with a poor standing wave ratio.
ratio and temperature
So-called structure zone models were developed to describe the micro structure and ceramics of thin films as a function of the homologous temperature T < sub > h </ sub > that is the ratio of deposition temperature over melting temperature.
The ratio between the value of the energy gap at zero temperature and the value of the superconducting transition temperature ( expressed in energy units ) takes the universal value of 3. 5, independent of material.
where is the difference in density of particles separated by a height difference of, is Boltzmann's constant ( namely, the ratio of the universal gas constant,, to Avogadro's number, ), and is the absolute temperature.
The tendency is to run lean, an equivalence ratio less than 1, to reduce the combustion temperature and thus reduce the NOx emissions ; however, running the combustion lean makes it very susceptible to combustion instability.
On average, the gas molecules move from the cold side toward the hot side whenever the pressure ratio is less than the square root of the ( absolute ) temperature ratio.
This causes the boiling point of the mixture to rise, which in turn results in a rise in the temperature in the vapor, which results in a changing ratio of A: B in the gas phase ( as distillation continues, there is an increasing proportion of B in the gas phase ).
The cut-off ratio can be expressed in terms of temperature as shown below:
The flame temperature can be approximated to the adiabatic flame temperature of the fuel with corresponding air-to-fuel ratio and compression pressure,.
The Redlich – Kwong equation is adequate for calculation of gas phase properties when the ratio of the pressure to the critical pressure ( reduced pressure ) is less than about one-half of the ratio of the temperature to the critical temperature ( reduced temperature ):
Metallotropic LCs are composed of both organic and inorganic molecules ; their LC transition depends not only on temperature and concentration, but also on the inorganic-organic composition ratio.
The addition of long chain soap-like molecules leads to a series of new phases that show a variety of liquid crystalline behavior both as a function of the inorganic-organic composition ratio and of temperature.
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