The wrist-pulse is a kind of signals, from which a lot of physiological and pathological status of patients are deduced according to traditional Chinese medicine theories. This paper designs a new optic fiber wrist-pulse sensor that based on a group of FBGs. Sensitivity of the optic fiber wrist-pulse measurement system reaches 0.05% FS and the range reaches 50kPa. Frequency response is from 0 Hz to 5 kHz. A group of typical pulse signal is given out in the paper to compare different status of patient. It will improve quantification of pulse diagnosis greatly.
In automatic fingerprint identification system, incomplete or rigid template may lead to false rejection and false matching. So, how to improve quality of the template, which is called template improvement, is important to automatic fingerprint identify system. In this paper, we propose a template improve algorithm. Based on the case-based method of machine learning and probability theory, we improve the template by deleting pseudo minutia, restoring lost genuine minutia and updating the information of minutia such as positions and directions. And special fingerprint image database is built for this work. Experimental results on this database indicate that our method is effective and quality of fingerprint template is improved evidently. Accordingly, performance of fingerprint matching is also improved stably along with the increase of using time.
Our work is to investigate the imaging performance of a direct, full-field prototype digital mammography detector as a function of x-ray exposure and detector operational conditions for digital mammography and advanced applications such as tomosynthesis. Theoretical and experimental methods previously developed for the study of small-area prototype detectors have been applied to the investigation of spatial frequency dependent detective quantum efficiency [DQE(f)] of the full-field prototype detector, which has 2816 x 2048 pixels with 85 μm pixel size. The focus of our study is the impact of scaling up the detector design on imaging performance, e.g. electronic noise, readout rate and image artifacts. The results showed that DQE(f) of the full-field detectors is in the same range as that measured from the small-area prototype detector, both of which are superior to existing technologies based on indirect detection. However DQE(f) drops more rapidly than the small-area prototype as exposure decreases, which is to be expected from the higher electronic noise of the full-field detector. Lag and ghosting, both of which can introduce image artifacts, were studied at typical screening mammography image intervals. The effect of lag can be eliminated with frequent update of the offset images. Ghosting at x-ray dose equivalent to a single view mammogram is negligible.