Wyniki wyszukiwania - BazTech

1

Comparisons of envelope morphological filtering methods and various regular algorithms for surface texture analysis

Podulka Przemysław

Metrology and Measurement Systems

|

2020

|

Vol. 27, nr 2

243--263

EN

In this paper both envelope approach and morphological filters for characterisation of surface textures were proposed, applied and thoroughly examined. Obtained results were compared with those received after appliance of commonly-used algorithms. The effect of appliance of proposed procedures on surface topography parameters (from ISO 25178 standard) was taken into consideration. The following types of surface textures were assessed: two-process plateau-honed cylinder liners, plateau-honed cylinder liners with additionally burnished dimples, turned piston skirts, grinded and/or isotropic topographies. It was assumed that envelope characteristics (envelope filtration) can provide results useful for assessments of deep and/or wide oil-reservoirs especially when they are edge located. Moreover, some near-valley areas of surface texture details can be less distorted when envelope filtering is accomplished. It was also found that closing and/or opening envelope filtration can be valuable for reduction of some surface topography measurement errors.

2

Metoda segmentacji obrazów mikroskopowych komórek roślinnych znakowanych radiograficznie do wyznaczania poziomu syntezy DNA w jądrach komórkowych

Gocławski J., Sekulska-Nalewajko J., Anioł P.

Automatyka / Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie

|

2007

|

T. 11, z. 3

75-87

PL

W artykule przedstawiono algorytm segmentacji autoradiogramów preparatów mikroskopowych komórek korzenia rzodkiewki (Raphanus sativus) wybarwionych metodą Feulgena. Celem segmentacji jest wyróżnienie obszarów skupień znacznika, co daje podstawą do dalszej oceny ilościowej poziomu syntezy kwasu nukleinowego (DNA) w jądrach komórkowych. Tempo namnażania materiału genetycznego może sygnalizować zaburzenia procesu wzrostu roślin powodowane różnymi czynnikami szkodliwymi w środowisku. Badane mikroskopowe obrazy autoradiograficzne są poddawane odwzorowywaniu z przestrzeni koloru RGB do HSV, filtracji medianowej, operacjom morfologicznym i w końcu progowaniu w celu znalezienia obiektów markera i powierzchni jąder komórkowych. Operacje te umożliwiają kompensację nierówności tła i redukcję artefaktów. Zastosowano dwa różne sposoby obróbki w celu wyodrębnienia dużych i małych skupień markera. Proponowany algorytm został zrealizowany w środowisku MATLAB 7 a wyniki segmentacji uzyskane dla serii 10 obrazów autoradiogramów zostały zweryfikowane pozytywnie przez cytologów.

EN

This paper presents the segmentation algorithm for autoradiograms of microscopic slices made of radish (Raphanus sativus) root meristematic cells stained with the Feulgen method. The segmentation purpose is the separation of isotopic marked agglomeration areas, what makes the base for subsequent quantitative discrimination of nucleic acid (DNA) synthesis level. The speed of genetic material multiplication can indicate the distortions of plant growth caused by various factors harmful for the environment. The investigated autoradiographic microscopic images are mapped from RGB to HSV colour space, median filtered, processed by morphological operations and finally thresholded to find the searched marker objects and nuclei surfaces. These operations enable image background equalization and artefact reduction. Two different paths of processing have been applied to extract small and big marker agglomerations. The proposed algorithm has been developed in MATLAB 7 environment and segmentation results for the series of 10 autoradiograms have been positively verified by cytologists.

3

Evaluation of the shape-varying structuring element in QRS detection for ECG compression

Tadejko P., Rakowski W.

Image Processing & Communications

|

2005

|

Vol. 10, no 2

27-38

EN

Morphological operations are simple mathematical constructs, which have led to effective solution for many problems in signal and image processing. These solutions employ discrete operators (structuring element) and are applied to digitized signals. The paper presents the mathematical morphology approach to the recognition and classification of heart rhythms on the basis of electrocardiogram (EGG) waveforms. The main part in recognition is based on the morphological niters characterization of the QRS complexes. In this work, we present morphological filtering as a preliminary step for compression of ECG data using image compression algorithms. To corn-press the ECG data using for example JPEG2000, SPITH or other codec, the one-dimensional ECG sequence needs to be processed to produce a two-dimensional matrix. Detecting operator designed for creating sequence is controlled by the shape and size of the structuring element. We compare how shape and length of this element can affects sensitivity detection algorithm based on amplitude and slope. The performance of the algorithm is evaluated with standard MIT/BIll arrythmia database.