Leszek Chmielewski

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The influence of the scale of a fuzzy membership function used to fuzzify a histogram is analysed. It is shown that for a class of fuzzifying functions it is possible to indicate the limit for fuzzification, at which the mode of the histogram equals the mean of the data accumulated in it. The fuzzification functions for which this appears are: the quadratic(More)
Automatic quality inspection of ferrite products is difficult as their surfaces are dark and in many cases covered with traces of grinding. A two-stage vision system for detection and measurement of crack regions was devised. In the first stage the regions with strong evidence for cracks are found using a morphological detector of irregular brightness(More)
In image registration it is vital to perform matching of those points in a pair of images which actually match each other, and to postpone those which do not match. It is not always known in advance, however, which points have their counterparts, and where are they located. To overcome this, we propose to use the Hausdorff distance function modified by(More)
4152 Background: PET scanning is an established modality that is useful in the clinical management of squamous cell carcinoma (SCC) of the head and neck and esophagus. This study evaluates the usefulness of PET scans in the management of anal SCC. METHODS Prospective case series of all patients treated for SCC of the anus between 2002 and 2006 in a(More)
Quality assessment in external beam radiotherapy necessitates for an efficient and robust tool for comparing the planned and realised geometry of the treatment. Such a tool using the modified Hausdorff distance measure has been developed and successfully introduced to clinical practice. The majority of steps of the method are automatic. The user specifies(More)
A simple method for retrieving local length and orientation of a curve represented as a set of edge elements (inter-pixel boundaries) is proposed. This entirely local method is based on classifying the layout of an edgel and its closest neighbours and resolves itself to referencing a small look-up table. No “smooth” representation such as a fitted(More)
PURPOSE To compare reproducibility of set-up for two different treatment techniques for external irradiation of the breast. METHODS AND MATERIALS In total, the analysis comprised 56 pairs of portal and simulator films for 14 consecutive patients treated following breast conserving therapy and 98 pairs of portal and simulator films for 20 consecutive(More)
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