The article analyzes the requirements for increasing the probability of conformity assessment of products. To increase the probability of measuring inspection, there have to be applied more precise measuring systems; performed multiple observations of the investigated quantity. An analysis was conducted for each of the ways.
The results of the evaluation of the object of inspection parameters are inevitably related to the uncertainty due to the imperfection of this procedure, equipment and the influence of external random factors. Reducing this effect is especially important within certain limits around the values of the tolerance interval with simultaneous reduction of the quantity of additional measurements.
To avoid limitations, an adaptive successive decision-making method for compliance was offered. At the start of the decision-making process, based on the actual relationship between the length of the tolerance interval and the uncertainty of measurement, there were found the initial relative tolerance limits (upper and lower) that correspond to the 95%-probability of making a decision. In accordance to these relative tolerance limits there were determined tolerance limits for the primary measurement, with which the primary measurement result is compared. In the case when the primary measurement result goes beyond the tolerance interval, an adaptive procedure is passed by performing additional measurements until their average value falls within the tolerance interval. Number of successive steps determines for the permissible "residual" probability of making a false decision on the correspondence of the object. This probability depends on the parameters of the probability density function of the investigated quantity.
Application of the method allows increase probability of making a correct decision about compliance for each inspected object and in comparison with known methods, does not significantly affect the decrease in productivity and increase the cost price of the product.
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