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Signals propagate at the speed of sound in the medium (almost always water), and maximum PRF depends upon the size of the object being examined. For example, the speed of sound in water is 1,497 m/s, and the human body is about 0.5 m thick, so the PRF for ultrasound images of the human body should be less than about 2 kHz (1,497/0.5).
The received signals from multiple PRF are compared using the range ambiguity resolution process. Each range sample is converted from time domain I/Q samples into frequency domain. Older systems use individual filters for frequency filtering.
The software aqion is shipped with a set of example solutions (input waters) and a tutorial how to attack typical water-related problems (online-manual with about 40 examples). More examples and exercises for testing and re-run can be found in classical textbooks of hydrochemistry.
An alternative to a planar array is a reflector antenna in combination with a digital feed array, which is of special interest for low frequency radar systems operating in L- and P-band (1 m), [11] combines the capabilities of digital beamforming with the high directivity of a large reflector antenna.
Ground targets further than this range cannot be detected, so the PRF can be quite high; a radar with a PRF of 7.5 kHz will return ambiguous echoes from targets at about 20 km, or over the horizon. If however, the PRF was doubled to 15 kHz, then the ambiguous range is reduced to 10 km and targets beyond this range would only appear on the ...
Pourbaix diagram of iron. [1] The Y axis corresponds to voltage potential. In electrochemistry, and more generally in solution chemistry, a Pourbaix diagram, also known as a potential/pH diagram, E H –pH diagram or a pE/pH diagram, is a plot of possible thermodynamically stable phases (i.e., at chemical equilibrium) of an aqueous electrochemical system.
The toxicity of ammonia is dependent on both pH and temperature and an added complexity is the buffering effect of the blood/water interface across the gill membrane which masks any additional toxicity over about pH 8.0. The management of river chemistry to avoid ecological damage is particularly difficult in the case of ammonia as a wide range ...
Waterproofing with two component system. In buildings using earth sheltering, too much humidity can be a potential problem, so waterproofing is critical. Water seepage can lead to mold growth, causing significant damage and air quality issues. Properly waterproofing foundation walls is required to prevent deterioration and seepage.