Abstract: The method for examining trees comprises directing ground penetrating radar signals into a tree using a radar apparatus connected to a microprocessor control and data acquisition unit via an interface. The tree to be examined is scanned with the radar unit after the radar velocity for that tree is calibrated. The tree is scanned at a selected elevation either by moving a single radar unit along the bark of the tree in a circumferential manner or by moving a radar signal transmitter substantially diametrically opposed to a radar signal receiver along the bark of the tree in a circumferential manner. The microprocessor control and data acquisition unit controls the radar unit and stores and digitizes radar signals for generating a real-time radargram. A cross-sectional map of the tree, a map of the severity, shape, size and location of internal decay and a map of the thickness of remaining wood are then generated from the radargram and the ensemble of saved radar signals.

Abstract: The Noise Suppressor II provides procedures and add-on units, which are attached to standard analog or digital ultrasonic flaw detector instruments for either suppressing noise spikes that clutter the flaw detector screens, or other undesired signals, or enhancing weak, barely detectable signals. The add-on units may do both simultaneously as well. Each unit includes an adjustable filter so that a user may tune the filter bandwidth to a specific range within the overall transducer band that coincides with the signal to be either suppressed or enhanced.

Abstract: The disclosure relates to a system for nondestructive evaluation (NDE) of material flaw characteristics. The NDE system, after being trained on previously-acquired experimental data, is given an assigned NDE task by the inspector and/or remote observer. This task is requested via a small keyboard on the system control unit or remotely. The system then issues detailed commands to stepping motors in its transducer-positioning mechanism (scanner) and to logic circuits in the ultrasonic (UT) pulser/receiver to establish the sequence of transducer (probe) translation and orientation changes and the frequency, pulse-width, and pulse repetition interval used to energize the probe. Shaft-position encoders in the scanning mechanism are used to insure faithful following of the commanded position/orientation sequence.

Abstract: A system for detecting and measuring subsurface fatigue cracks wherein acoustic pulse-echo data from the crack under test are manipulated to extract all acoustic characteristics by means of a Fourier operation, deconvolution and inverse Fourier operation, providing a spectral and cepstral analysis on these data and then utilizing the results of the spectral and cepstral analysis to obtain parameters which are utilized in an adaptive learning network to provide crack length measurements.