تخصيص قابليت اطمينان با رويكرد تاب آوري زيرسيستم ها با روش فو مطالعه موردي : صندلي پران هواپيماي جنگنده

Allocating Reliability adopting Subsystem Resilience Approach taking up Foo Method

تخصيص، يكي از فعاليت هاي مهم و اساسي در فرآيند قابليت اطمينان مي باشد با توجه به اهداف مورد نظر، قابليت اطمينان زير سيستم ها و اجزاي تشكيل دهنده ي آن را تعيين مي نمايد و چنانچه به درستي انجام نشود، دستيابي به اهداف قابليت اطمينان براي كل سيستم امكان پذير نخواهد بود. براي تخصيص قابليت اطمينان روش هايي ارائه شده كه خالي از نقص نبوده است. در اين پژوهش پنج فاكتور پيچيدگي، تكنولوژي جديد، زمان عملكرد، محيط و تاب آوري زيرسيستم ها در نظر گرفته شده است و هدف اين است كه رويكردي جديد در تخصيص قابليت اطمينان به روش امكان پذيري هدف در نظر گرفته شود تا بتوان قطعات و زيرسيستم هاي توليد يا خريداري شده از تامين كنندگان مختلف را براساس قابليت اطمينان و تاب آوري مورد نظر در زمان شوك و شرايط نامطلوب، بررسي و اندازه گيري كرد. براي به دست آوردن ضريب اهميت پنج فاكتور ذكر شده ابتدا با استفاده از روش هاي تصميم گيري با معيارهاي چند گانه و نظر خبرگان و يا به صورت كيفي، زير معيارهاي تاب آوري اندازه گيري و پس از در نظر گرفتن روابط ميان معيارهاي تاب آوري، جهت به دست آورن وزن آنها از روش ANP استفاده شده است. نهايتا نتايج به دست آمده براي هر زيرسيستم از يك محصول خاص براي چند تامين كننده به روش فو با پنج فاكتور مذكور بررسي و اندازه گيري و در نهايت اعتبار سنجي مي شود.

Abstract: All systems from big to small, must have adequate reliability. If that is not the case, a disturbance in the proper functioning of a system can bring about tremendous economic and human losses. From another perspective, reliability is regarded as one of the quality features of component parts, products and large and complicated systems playing an essential role in the performance of latter equipment. In today s world competitive market, reliability is among highly focused issues. The concept allocation is one of the crucial and decisive activities in the reliability process, which, by considering the intended targets-specifies the reliability of subsystems and their component ingredients. This concept –i.e., allocation- if not realized appropriately, the attainment of reliability targets for the entire system would be an impossible undertaking. For allocating reliability, there are some methods offered by researchers, which methods are not without defects. Four factors are presented in this regard: Complexity, state-of-the art technology, operating time, and the ambient conditions. This research, however, considers five factors؛ namely, the four above mentioned parameters plus the subsystems resilience factor. The objective followed in this researcher is proposing a new approach in which the reliability allocation by adopting the targets feasibility is considered such that the component parts and subsystems of manufacturing systems or those which are of purchased from different suppliers are investigated and measured as regards the intended reliability and resilience in times of shock and under adverse conditions. In order to obtain the significance coefficients of the above five factors, first by invoking MCDM measuring procedures and the elite experts viewpoints or on occasions qualitative procedures, the resilience sub-criteria are measured. Then, by way of considering the relationship existing among resilience measures, we embarked on exploiting the ANP method to obtain the relevant weight of each parameter. In the final stage, considering a few suppliers and by resorting to Foo procedure alongside the five above named factors, the results obtained for each subsystem of the specified product are examined, measured and eventually validated.