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Ocena wiarygodności badania densytometrycznego

Matuszewski M., Wiśniewska M.

Przegląd Spawalnictwa

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2016

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R. 88, nr 10

118--121

PL

W pracy dokonano oceny wiarygodności badania densytometrycznego do określenia wysokości wad spoiny. Dokonano pomiarów gęstości optycznej obrazów i przeprowadzono niezbędne obliczenia wynikające z obowiązującej normy. Wykazano dużą niejednoznaczność wyników i obliczeń. Na podstawie analizy, z uwagi na dużą rozbieżność wyników, wykazano jak ważne jest właściwe planowanie badań nieniszczących w kontroli jakości złączy spawanych oraz postępowanie w tych badaniach.

EN

In this paper assesses the credibility of densitometry to determine the amount of defects in the weld. Measurements were made of optical density images and the necessary calculations were performed under the applicable standard. Demonstrated great ambiguity of the results and calculations. Based on the analysis, due to the large discrepancy results demonstrated the importance of proper planning nondestructive testing quality control of welded joints and procedure in these studies.

2

The influence of bone tissue microstructure' parameters on bone mineral density parameter computed within the computer simulation process

Binkowski M., Dyszkiewicz A., Wróbel Z.

Journal of Medical Informatics & Technologies

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2005

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Vol. 9

49--55

EN

The given article was created with reference to lack of correlation between results from densitometry test of bone tissue and its mechanical strength. The changes of bone mechanical strength cannot be solely connected with changes of bone mineral density with micro structural construction of bone tissue. The article describes the research using a computer simulation where changes of physical density and parameters of bone microstructure were modelled. The influences of those parameters for changing the bone mineral density have been computed. It has been calculated during simulation process similar to the way it has been provided from densitometry test. The computation process has been carried out on the basis of computer method of simulation of x-ray radiation propagating through the object and had been was created and tested in the previous research. The model of tested object was defined by spatial high resolution distribution of density. The simulation was executed on a sample of bone tissue. The input data to the model of sample were series of cross-sections obtained previously from micro CT of an animal sample. The changes of parameters were simulated in the model based on a method of 2D image processing. The procedure was used to reduce the trabecular surface for all cross-sections. The results of the algorithm were measured during algorithm process. Images were also analyzed by software to measure parameters of microstructure. It gave a chance to estimate the correlation between measured parameter and parameters of microstructure. The applied method of simulation of attenuation of x-ray radiation allowed to produce densitometry image and to compute parameter similar to bone mineral density. The analysis of obtained results shows how the bone mineral density computed from simulation depends on changes of parameters of microstructure.

3

Simulation of the reaction of X-ray radiation with an object while densitometry tests

Binkowski M., Dyszkiewicz A., Wróbel Z.

Journal of Medical Informatics & Technologies

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2004

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Vol. 8

MM95--104

EN

The computer modelling of absorption effect of X-ray radiation in the bone tissue was analysed. An image, which is produced as a result of X-ray absorption was computed based on the absorption law. The simulation enables to define dimensions and resolution of space where the experiment will be realised. A model of a sample contains information about its geometry and distribution of density. It can be made as simple solids or loaded from external source, like files. This method may be useful to load information about bone microstructure into the simulation space. A source of X-ray radiation was defined as a plate, which has initial radiation intensity. Rules of radiation propagation were simplified to straight model where radiation propagates in the direction perpendicular to the surface of detector which records an image. The image is generated by computation of partial absorption for each space elements. The results of simulation of model of micro-structure of bone tissue are presented. They can be useful to show when densitometry test does not contain accurate and full information about bone tissue. It may by helpful in the future while searching for reasons of incomplete correlation between mineral density and mechanical strength.