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Reliability based design optimization

The response calculation or the system probability of failure variance represented by the model is not an end in itself ; it is just a performance indicator. Often, our customers want to take a decision (to proportion structural elements, to sample a maintenance plan) in agreement with the goal formulated by the ordering customer (the client or the competent safety authority). PHIMECA Engineering has developed a series of tools to address its concerns.

Global sensitivity analysis

The objective of the global sensitivity analysis is to quantify the portion of variability by each of the input variables to the response variability. These indicators have to permit the engineer to know where to invest to improve its system robustness while reducing the state variables variability which characterizes it.
The analysis of variance (ANOVA) particularly, uses the response variance as a indicator of variability and the conditional variances as indicator of contributions. The analysis of covariance (ANCOVA), generalizes the ANOVA if the input parameters are correlated.


Analysis of reliability sensitivity

The analysis of reliability sensitivity is interested in probability of failure variation (reliability indicator) according to the parameters of the probabilistic model to measure the assurance that it could be given to the estimated probability or to adjust it. The probability of failure gradient according to the decision parameters (average or fractile value, or input parameters variances) permits the engineer to see what factors need to be acted on to reach the reliability level fixed by its ordering customer.

Use of probabilistic performance indicators in an optimization loop

Fortified by probabilistic performance indicators (average, variances, probabilities) and by sensitivity associated measures, PHIMECA Engineering can help you to explain your optimization problem by identifying the decision parameters on which you can do something, your goals and constraints about which you must be confronted, and to resolve it.

Reliability-based Design Optimization


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Mentions légales

PHIMECA engineering is an engineering company specialized in the optimization, the reliability and the robustness of products and structures.
Its goal is to provide solutions for robust engineering based on solid scientific foundations, entrepreneurial spirit and moral values shared by all its collaborators.