TY - CONF A1 - Pavlovic, Mato T1 - Multi-Parameter Approach to Structural Integrity T2 - 9th International Conference on NDE in Relation to Structural Integrity for Nuclear and Pressurized Components CY - Seattle, WA, USA DA - 2012-05-22 PY - 2012 AN - OPUS4-27006 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pavlovic, Mato A1 - Ronneteg, U. A1 - Müller, Christina A1 - Ewert, Uwe A1 - Boller, C. T1 - Safe product design - the role of the NDE reliability analysis N2 - When pushed to the limits of their detection capability, NDE systems do not produce consistent hit/miss indications. Their capability of detecting small defects is therefore expressed in terms of POD. An adequate NDE system is required to ensure the structural integrity. In conventional signal response analysis, the POD is expressed as a function of the defect size, and its adequacy for the inspection task is tested against the maximum allowable defect size which will not undermine the structural integrity. Analyses of modern structures show that other parameters, beside the defect size, can both significantly influence the POD and determine the severity of the defect for the structure. Within the multi-parameter reliability analysis, the POD is expressed as a function of those influencing parameters. When determining the adequacy of the NDE system, the capability of detecting a defect has to be expressed and tested against the critical value of exactly that parameter that determines defects severity for the structure. Failing to do so can lead to a rejection of the healthy, or acceptance of the bad part. The principle is demonstrated on the example of the Transmit-Receive Longitudinal (TRL) ultrasonic inspection of the iron cast component for semi-elliptical surface defects. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 16.04.2012 KW - Reliability KW - Probability of detection (POD) KW - Multi-parameter KW - Ultrasonics KW - Transmit receive longitudinal (TRL) PY - 2012 SN - 978-0-620-52872-6 SP - 1 EP - 9 (Paper 310) AN - OPUS4-27581 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pavlovic, Mato A1 - Takahashi, Kazunori A1 - Müller, Christina T1 - Probability of detection as a function of multiple influencing parameters N2 - It is not always only the size of the flaw that determines the severity of the flaw for the structure. In such cases, it is important to express the capability of the non-destructive testing (NDT) system to detect a flaw with respect to exactly those parameters that determine flaw severity. The multi-parameter reliability model presented in this article shows a way of calculating and expressing the probability of detection (POD) as a function of different influencing parameters, using numerically simulated NDT system responses and experimentally measured responses. A successful application of the model is demonstrated on the data from a transmit-receive longitudinal (TRL) ultrasonic inspection of a cast iron component. The POD of the surface-breaking semi-elliptical crack-like flaw is expressed as a function of its depth and length. In a direct comparison with the conventional signal response analysis, where the POD is expressed as a function of only the flaw size, the method provides a more comprehensive estimation of the reliability of the NDT system. PY - 2012 DO - https://doi.org/10.1784/insi.2012.54.11.606 SN - 0007-1137 VL - 54 IS - 11 SP - 606 EP - 611 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-27580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Christina A1 - Bertovic, Marija A1 - Pavlovic, Mato A1 - Kanzler, Daniel A1 - Ewert, Uwe A1 - Pitkänen, J. A1 - Ronneteg, U. T1 - Holistically evaluating the reliability of NDE systems - paradigm shift N2 - New methodologies for evaluating the reliability of NDE systems are discussed in accordance with the specific requirements of industrial application. After a review of the substantive issues from the previous decades, the go forward guidance is concluded. For high safety demands a quantitative probability of detection (POD) created from hit miss experiments or signal response analysis and ROC (Receiver Operating Characteristics) are typically created. The modular model distinguishes between the influence of pure physics and technique, industrial application factors and the human factor and helps to learn what factors are covered by modelling, open or blind trials. A new paradigm is offered to consider the POD or reliability of the system as a function of the configuration of input variables and use it for optimisation rather than for a final judgement. New approaches are considered dealing with real defects in a realistic environment, affordable but precisely like the Bayesian approach or model assisted methods. Among the influencing parameters, the human factor is of high importance. A systematic psychological approach helps to find out where the bottlenecks are and shows possibilities for improvement. T2 - 18th WCNDT - World conference on nondestructive testing CY - Durban, South Africa DA - 16.04.2012 KW - Reliability of NDE KW - POD KW - ROC KW - Modular Model KW - Multiparameter-POD KW - Bayesian Approach KW - Human Factor PY - 2012 SN - 978-0-620-52872-6 SP - 1 EP - 14 (Paper 591) AN - OPUS4-27579 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -