ارايه‌ي شيوه‌يي جديد در تخصيص پايايي با استفاده از معيارهاي تعيين ميزان اهميت در پايايي

A New Technique in Reliability Allocation using Reliability Importance Measure

مهندسي پايايي و متعاقب آن تخصيص پايايي به زيرسيستم ها در فاز طراحي، عوامل مهمي هستند كه توجه به آنها در طراحي محصول ضروري است. تخصيص پايايي، موجب دست‌يابي به محصولي پايا، ارزان و در عين حال مطابق با خواسته‌هاي مشتري، رقابت پذير و سازگار با محدوديت هاي ما و نيز بهبود روش هاي طراحي و ساخت مي‌شود. محققين بسياري از پارامترهاي فرايند تخصيص پايايي را با ايده‌هايي متفاوت ارايه داده اند كه با آناليز آنها، ضعف هايي آشكار شده است. يك جنبه‌ي مهم در نظر گرفته نشده، ميزان اهميت زيرسيستم ها با توجه به مكان آنها در چيدمان كل سيستم و ميزان تاثير آنها بر پايايي كل سيستم است. در اين نوشتار با استفاده از معيارهاي تعيين ميزان اهميت در پايايي، بر اين ضعف غلبه شده است. با مقايسه‌ي نتايج اجراي شيوه‌ي جديد و دو مورد از پركاربردترين شيوه‌هاي موجود در متون علمي بر مثال‌هاي آورده شده، برتر بودن نتايج حاصل از شيوه‌ي جديد مورد تاييد قرار گرفته است.

In the process of designing a product or a physical system, reliability engineering is an important factor to be considered. Also, as an essential step in reliability evaluation during the design phase, it is necessary to allocate reliability to subsystems, in such a way that full system reliability is satisfied. Performing this process, which is called reliability allocation, creates a more reliable and competitive system, which, at the same time, is compatible with our limitations. The consequences of considering this phase in designing a product are improved design and manufacturing methods, and, as a result, it is possible to gain cheap and reliable products compatible with customer demand. Many parameters that exist in the process of reliability allocation have been generated based on research investigations. These techniques have different attitudes towards performing an allocation process. By analyzing these approaches, the researchers discovered remarkable disorders. These disorders are consequences of weaknesses, some of which all techniques share. One important aspect not considered in these techniques, and considered to be a great weakness, is the importance of subsystems, regarding their place in system configuration and their contribution to full system reliability. In this study, according to the importance and effectiveness of reliability importance measures, we have utilized them as an approach to suggest a new and effective technique. In this process, we use the technique of reliability importance measures to propose a new way to overcome this weakness, and, in two examples, will show the effects of using these measures in the process of reliability allocation. Based on a comparison between the new technique and the two most applicable techniques in literature; ARINC and MAXIMAL ENTROPY, using one hypothetical and one real example, we have shown the preferable results of the new technique.