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Controller peripheral component interconnect bus two

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controller Peripheral component interconnect bus Two analog Sixteen digital
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hit connector upon which light emitting diodes can be directly connected for a hit readout. Next is the parametric connector with two analog inputs, as well as eight digital inputs and eight digital outputs for industrial control interfacing. The last connector shown on the top right of Fig. 4, the real time control connector, is the interface connector for attaching additional cards for time synchronized operation through a daisy chain ribbon cable, providing exact timing information between channels for location determination using time-of-flight analysis between hit arrivals. Acoustic Emission Signal Processing Features What are features and why does an acoustic emission system process them? First of all, acoustic emission features describe the shape and content of a detected waveform. When looking at many waveforms and trying to distinguish one from another, it might be observed that one waveform is higher in amplitude than another waveform, is longer in duration or is at a different frequency. The purpose of feature extraction is to extract as much information about the shape and content of a waveform to differentiate it from other waveforms with different source mechanisms. The more features extracted from the waveform, the more detailed its description. With enough of these waveform descriptors, features can be used in combination to virtually reconstruct the acoustic emission waveform. If information is available about the acoustic emission peak amplitude, the rise time, duration and frequency content, then the waveform can be visualized. This is the basis for neural network and pattern recognition techniques on feature data. Waveform shapes can be distinguished from each other by analyzing their features in combination. Acoustic emission features are also important because they provide waveform data reduction or compression of the waveform, allowing much faster digital signal processing and pattern recognition than the waveform alone allows. To illustrate the amount of data reduction, assume an 8000-sample, 16-bit waveform. To store and process this waveform requires storing and processing of 16 kilobytes of sample data. However, processing 10 acoustic emission features adequately provides a good description of the waveform yet requires only the storage and processing of about 32 bytes of data or less. This 500-fold data reduction allows acoustic emission systems to be extremely fast in the number of hits per second that they can process. In summary, extraction of multiple features provides a full description of the acoustic emission waveform at very high compression ratios to ensure very fast digital signal processing.
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