patency (plural patencies). ( 1 medicine) The degree of openness of a tube, such as a blood vessel or catheter; the relative absence of blockage. ( 2 uncountable) Obviousness; clarity.
Maximum Length: 16' with a standard cable, Up to 50' with a high quality cable. VGA is an analog signal and so as distance increases the quality will decrease. A lot of factors can determine the maximum cable length, but for low resolutions (up to 800x600) you can reach 100 feet and beyond without too much trouble. For mid-range resolutions of 1280x1024/1024x768 you can typically reach somewhere between 50 to 100 feet.
Attenuation coefficients are used to quantify different media according to how strongly the transmitted ultrasound amplitude decreases as a function of frequency. The attenuation coefficient () can be used to determine total attenuation in dB in the medium using the following formula:As this equation shows, besides the medium length and attenuation coefficient, attenuation is also linearly dependent on the frequency of the incident ultrasound beam.n engineering, attenuation is usually measured in units of decibels per unit length of medium (dB/cm, dB/km, etc.) and is represented by the attenuation coefficient of the medium in question.