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Czabanski R.,Silesian University of Technology | Jezewski J.,Instytut Techniki i Aparatury Medycznej | Janusz W.,Instytut Techniki i Aparatury Medycznej | Sikora J.,Klinika Poloznictwa i Ginekologii SLAM | Jezewski M.,Silesian University of Technology
Ginekologia Polska | Year: 2013

Objectives: Fetal monitoring based on the analysis of the fetal heart rate (FHR) signal is the most common method of biophysical assessment of fetal condition during pregnancy and labor. Visual analysis of FHR signals presents a challenge due to a complex shape of the waveforms. Therefore, computer-aided fetal monitoring systems provide a number of parameters that are the result of the quantitative analysis of the registered signals. These parameters are the basis for a qualitative assessment of the fetal condition. The guidelines for the interpretation of FHR provided by FIGO are commonly used in clinical practice. On their basis a weighted fuzzy scoring system was constructed to assess the FHR tracings using the same criteria as those applied by expert clinicians. The effectiveness of the automated classification was evaluated in relation to the fetal outcome assessed by Apgar score. Material and methods: The proposed automated system for fuzzy classification is an extension of the scoring systems used for qualitative evaluation of the FHR tracings. A single fuzzy rule of the system corresponds to a single evaluation principle of a signal parameter derived from the FIGO guidelines. The inputs of the fuzzy system are the values of quantitative parameters of the FHR signal, whereas the system output, which is calculated in the process of fuzzy inference, defines the interpretation of the FHR tracing. The fuzzy evaluation process is a kind of diagnostic test, giving a negative or a positive result that can be compared with the fetal outcome assessment. The present retrospective study included a set of 2124 one-hour antenatal FHR tracings derived from 333 patients, recorded between 24 and 44 weeks of gestation (mean gestational age: 36 weeks). Various approaches for the research data analysis, depending on the method of interpretation of the individual patient-tracing relation, were used in the investigation. The quality of the fuzzy analysis was defined by the number of correct classifications (CC) and the additional index QI - the geometric mean of the sensitivity and specificity values. Otrzymano Results: The effectiveness of the fetal assessment varied, depending on the assumed relation between a patientand a set of her tracings. The approach, based on a common assessment of the whole set of tracings recordedfor a single patient, provided the highest quality of automated classification. The best results (CC = 70.9% and QI = 84.0%) confirmed the possibility of predicting the neonatal outcome using the proposed fuzzy system based on the FIGO guidelines. Conclusions: It is possible to enhance the process of the fetal condition assessment with classification of the FHR records through the implementation of the heuristic rules of inference in the fuzzy signal processing algorithms. © Polskie Towarzystwo Ginekologiczne.

Mocha J.,Silesian University of Technology | Woznica T.,Instytut Techniki i Aparatury Medycznej
Przeglad Elektrotechniczny | Year: 2010

The paper presents a comparison of conducted and radiated electromagnetic emission (the measurement based on the IEC 61967 standards) generated by two microprocessor systems implemented in a Field Programmable Gate Array (FPGA). The same CPU core executing the same program was used in both systems. One of the systems was build using only internal resources of the FPGA, while the other used external SRAM as the program memory. (Electromagnetic emission of microprocessors systems implemented in FPGAs).

Woznica T.,Instytut Techniki i Aparatury Medycznej | Mocha J.,Instytut Techniki i Aparatury Medycznej | Badura G.,Instytut Techniki i Aparatury Medycznej | Wojcik D.,Silesian University of Technology | Surma M.,Silesian University of Technology
Przeglad Elektrotechniczny | Year: 2012

The paper attempts to estimate the impact of disturbances on the commercial medical device. As a source of disturbances the signals in accordance with current and proposed regulations and the signals produced by GSM system have been chosen. The signals were briefly characterized in time and frequency domain. The obtained results shows that obligatory recommendations could be insufficient in the evaluation of immunity of commercial medical devices on signals produced by radiocommunication systems.

The paper presents a test set-up for radio-electric emission pre-compliance tests, with a spectrum analyzer and a GTEM cell. The paper presents also results of the verification procedure carried-out to verify reliability of the measurement, together with discussion of basic technical problems, and potential sources of uncertainty in the presented set-up. (Radio-electric emission pre-compliance tests in a GTEM-cell with the use of a spectrum analyzer).

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