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Failure mode and effects analysis (FMEA) is a widely used technique for identifying, evaluating, and eliminating potential failures in production, system, and process. The traditional FMEA ranks the failure modes according to risk priority numbers (RPN), which are obtained by the multiplications of the crisp values of risk factors, such as occurrence (O), severity (S), and detection (D). However, the traditional FMEA is criticized for mishandling uncertain information and calculating RPN unreasonably. To overcome the above deficiencies, this study presents an advanced FMEA method combined with interval 2-tuple linguistic variables (ITLV) and technique for order preference by similarity to ideal solution (TOPSIS). In the proposed method, the evaluations given by different FMEA members based on their different linguistic term sets are represented by ITLVs, which are feasible and valid variables to effectively deal with uncertain information. The TOPSIS method is used to rank the risk priorities of failure modes by comprehensively considering all of risk factors. Finally, an application case is provided to illustrate the validity and robustness of the proposed method. [ABSTRACT FROM AUTHOR]

Teramethylpyrazine (TMP) is a pyrazine alkaloid with a variety of pharmacological effects and widely used in clinical practice. In this study,Monascusstrain M-3 with high TMP and low citrinin productions was screened from red yeast rice collected from different areas of Fujian province in China.Monascusstrain M-3 was further identified through molecular biological methods based on the sequencing of different gene regions. Results showed that primer set of β-tubulin-F/β-tubulin-R targeting the β-tubulin gene was more suitable for the identification ofMonascusstrain M-3. Based on comparative analysis of the results obtained by different primer sets,Monacusstrain M-3 was finally identified asMonascus purpureus. Then, the composition of culture medium and liquid state fermentation conditions ofMonacusstrain M-3 were optimized by single-factor experiment and central composite design of response surface methodology, with the purpose of optimizing the TMP productions. The optimum composition of culture medium and liquid state fermentation conditions are as follows: starch 5.1%, peptone 3.51%, Mg2SO40.1%, NaNO30.2%, KH2PO40.25%, fermentation temperature of 28.23 °C, fermentation time of 9 d, shaker speed of 180 r/min, inoculum size of 7.21% and loading volume of 100 mL/250 mL triangular flask. Under the optimum composition of culture medium and liquid state fermentation conditions, the TMP production ofMonacusstrain M-3 can reach 13.49 µg/mL. This study is expected to provide a new approach of TMP production through biosynthesis byMonascusstrain, and promote the further development of functional foods or medicines fromMonascusfermentation products. [ABSTRACT FROM AUTHOR]