Wyniki wyszukiwania - BazTech

1

Filtering of two-dimensional digital images using weighted averaging for adaptive selection of weights

Momot A., Wrobel J., Horoba K., Jeżewski M., Bernys M.

Journal of Medical Informatics & Technologies

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2012

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Vol. 20

93--99

EN

Many digital images, especially in biomedical fields, contain some disturbances. The image analysis depends on quality of the images that is why reduction or elimination (if it is possible) the disturbances is the key issue. There are many methods of improvement in the quality of the images and thus improve the quality of the image analysis, among them one of the simplest method is low-pass filtering such as arithmetic mean or its generalization, weighted mean. The basic problem of the weighted mean is the proper selection of the weights. This can be done using adaptive algorithms. This paper presents several such algorithms which are modifications of the existing weighted averaging methods created originally for noise reduction in electrocardiographic signal. The description of the new filtering methods and a few results of its application are also presented with comparison to existing arithmetic average filtering.

2

Comparison of instantaneous fetal heart rate extracted from abdominal and direct fetal electrocardiograms

Matonia A., Kupka T., Jezewski J., Momot A., Jeżewski M., Bernys M.

Journal of Medical Informatics & Technologies

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2012

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Vol. 19

101--107

EN

This work is an attempt to assess the reliability of indirect abdominal electrocardiography as an alternative technique of fetal monitoring. As a reference signal we used the simultaneously acquired direct fetal electrocardiogram. Each recording consisted of four signals acquired from maternal abdomen and the reference signal acquired directly from fetal head. The first stage of our study concerned the signal loss episodes. In order to reduce the influence of incorrectly detected R-waves, some certain validation rules were applied. In the second stage, the corresponding intervals determined on basis of both acquisition methods were matched and the accuracy of fetal heart rate measurement was evaluated. Although the accuracy of abdominal electrocardiography turned out to be slightly lower than reported for ultrasound method, it still has some unique features deciding of its prevalence in a certain circumstances.

3

A routing protocol for wireless network of bedside monitors in fetal surveillance system

Seredynski R., Horoba K., Roj D., Bernys M., Przybyla T., Jezewski J.

Journal of Medical Informatics & Technologies

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2012

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Vol. 21

27--33

EN

The paper presents the methodology of wireless network design, developed according to the requirements originating from existing wired fetal surveillance systems. The proposed network structure is based on popular radio frequency modules, operating in 433/866MHz band. The described solution is a simple and cost effective alternative to the wired networks, and it will vastly increase the mobility of fetal monitors. The authors also describe software tools which were designed for this purpose and the results of simulations performed on their basis.

4

Simultaneous recording and analysis of direct and indirect fetal electrocardiography

Matonia A., Jeżewski J., Kupka T., Horoba K., Bernys M.

Journal of Medical Informatics & Technologies

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2004

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Vol. 8

MM111--118

EN

Recording and analysis of fetal heart rate variability is still the most common method for detection of early symptoms of fetal hypoxia. However, fetal heart rate obtained via ultrasound describes only mechanical activity of fetus heart. Limitations of this technique have stimulated the development of fetal electrocardiography. It ensures more precise determination of fetal heart rate and, which is more important, enables assessment of the morphology of the fetal QRS complexes. In this paper two techniques of obtaining the fetal electrocardiogram are described and their comparative study is presented.