This paper presents a method of simplifying the diagnostic accuracy estimation for compressed mammograms. The proposed method consists of three main stages: a) the selection of abnormal structure features susceptible to wavelet compression method, b) subjective ratings of diagnostically important features and c) estimation of diagnostic pattern for processed mammograms. This pattern reflects diagnostic ability of radiologists using encoded images in clinical practice. Experimental pattern estimation confirmed even higher diagnostic quality of compressed to 1 bpp mammograms than their 12 bpp...
XVII IMEKO World Congress · TC10 · 2003 · Download
The paper considers the mathematical model for dischargers diagnosing, considering the value and the duration of the current’s impulse at the moment of commutation and synthesized the device for its realization using the sequence’s mathematical tool.
XVII IMEKO World Congress · TC10 · 2003 · Download
Mobile Flash-Cards in different technologies and formats are well suited to act as an exchangeable non volatile mass storage for data or program code in measurement devices and small automation systems. Due to the use in the fields of digital photography and multimedia applications, flash cards have been introduced into the market and are available in a standardized and compact way. Because of their mobile characteristics, their solid-state design, security features and an easy handling, they are an appropriate storage medium in measurement data acquisition, but furthermore in the field of...
XVII IMEKO World Congress · TC10 · 2003 · Download
Vittorio Belotti, Francesco Crenna, Rinaldo C. Michelini, Giovanni B. Rossi
Aim of this research is the development of a reliable automated procedure for the detection of wheelflat faults in railway diagnostics. This kind of fault occurs when the train wheel slides on the rail. The wheelflat produced by sliding is a relevant cause of acoustic pollution, passenger discomfort, damage to rails and boogies. A good wheelflat detection diagnostics is common interest, both, for railway and vehicles operators. The diagnostic method presented in this paper is based on the wavelet analysis of accelerometric signals obtained by an experimental campaign on a test train. The...
XVII IMEKO World Congress · TC10 · 2003 · Download
Neutral electrodes (grounding plates used in electrosurgical operations) were tested with thermo cameras in volunteers experiments. These experiments are difficult to perform and expensive. A new test device swaroTEST with a measuring board "electronic skin" simulates the relevant electrical features of human skin to replace volunteer experiments. This device consists of a three dimensional resistor network representing the electric features of the skin and muscle tissue, and a temperature sensing array (one transistor for each cm²) to measure the resultant temperature increase after a...
XVII IMEKO World Congress · TC10 · 2003 · Download
The object of the investigation presented in the paper are measurements related to diagnostics of induction motors. The described system is based on the measurement and spectral analysis of current feeding an electric motor. Diagnostic methods of motor windings making use of the current analysis are already known. The author proposes involving in this method also examination of mechanical defects, in particular, damages caused to bearings. In order to obtain positive results it is necessary to theoretically obtain information referring to the type of components that accompany the current...
XVII IMEKO World Congress · TC10 · 2003 · Download
The paper presents the introductory results in application to multi fault condition monitoring of mechanical systems in operation, in particular internal combustion engines. This generalization to multi dimensionality and multi fault condition monitoring is possible by utilizing transformed symptom observation matrix, and by successive application of singular value decomposition (SVD). On this basis one can make full extraction of fault related information from symptom observation matrix created by traditional monitoring technology. Moreover, by SVD we can create several independent fault...
XVII IMEKO World Congress · TC10 · 2003 · Download
In the paper a new homotopic method of fault diagnosis of analogue piecewise linear (PWL) circuits based on a large-deviation sensitivity model is presented. Homotopy maps one function f ( x ) into another g ( x ) by changing the homotopy parameter t ∈[0,1]. The idea of the method relies on using the function f ( x ) to the description of the circuit under test (CUT) in the non-faulty state and the function g ( x ) to the description of the faulty CUT. For verification of assumed fault hypotheses node homotopic paths are used. The method enables localisation and identification of parametric...
XVII IMEKO World Congress · TC10 · 2003 · Download
In this paper a soft fault diagnosis technique of analog linear circuits is presented. A Simulation-Before- Test (SBT) approach is used, where the fault dictionary is designed by circuit signatures obtained using ARX model identification.
XVII IMEKO World Congress · TC10 · 2003 · Download
Recently many articles discussing about shaft voltage and bearing currents and about their influence on operating life and reliability of sliding and anti-friction bearings appeared. Negative influence of electric current passing through bearings is known from beginning of the last century but new problems were occured with assotiation of electric machines feeding from static frequency converters. And just this problem is described in the article. We want to show our results of laboratory experiments and mathematical analysis of bearings damage in this paper.
XVII IMEKO World Congress · TC10 · 2003 · Download