Al-dhabi M. Models and methods of increase in trustworthiness of on-line testing in arithmetical digital components of safety-related systems

The thesis is devoted to questions of increase in trustworthiness of on-line testing for digital components of safety-related systems which control objects with the increased risk in energetic, transport and other branches. Array structures which are traditionally used in digital components significantly reduce a checkability of circuits which restricts trustworthiness of on-line testing. Input data obtained from sensors are approximate and contain most and least significant bits. In them, faults cause essential and inessential errors. Models of results and models of checking the computation paralleled in serial codes which provide distinguishing of essential and inessential errors for processing mantissas on circuits with the checkability raised by truncation of array structures are offered. On the basis of these models, the methods of on-line testing with checking by inequalities and the scanning check that increase trustworthiness in a normal mode, thanks to a high checkability of circuits, and in emergency mode, reducing influence of inessential errors on on-line testing are developed.