بهينه سازي نگهداري و تعميرات پيشگيرانه در يك سيستم چند وضعيتي

Optimization of Preventive Maintenance of Multi-state System

در اﯾﻦ ﺗﺤﻘﯿﻖ، روش ﻧﮕﻬﺪاري و ﺗﻌﻤﯿﺮات ﯾﮏ ﺳﯿﺴﺘﻢ ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺘﻪ اﺳﺖ. اﯾﻦ ﺳﯿﺴﺘﻢ در ﻟﺤﻈﻪ ﺷﺮوع در وﺿﻌﯿﺖ ﯾﮏ ﺑﻮده ﮐﻪ در آن ﺳﯿﺴﺘﻢ ﮐﺎﻣﻼ ﺳﺎﻟﻢ و ﻧﻮ ﻓﺮض ﻣﯽ ﺷﻮد. ﭘﺲ از ﻣﺪت زﻣﺎﻧﯽ ﺗﺼﺎدﻓﯽ، ﺳﯿﺴﺘﻢ ﺧﺮاب و ﺑﻪ وﺿﻌﯿﺖ ﺗﻌﻤﯿﺮ ﻣﯽ رود و ﭘﺲ از آن دوﺑﺎره ﺷﺮوع ﺑﻪ ﮐﺎر ﻣﯽ ﮐﻨﺪ. اﻣﺎ در اﯾﻦ وﺿﻌﯿﺖ ﻃﻮل ﻋﻤﺮ ﺳﯿﺴﺘﻢ ﺑﻪ ﻃﻮر ﺗﺼﺎدﻓﯽ ﮐﻤﺘﺮ از ﻃﻮل ﻋﻤﺮ آن در وﺿﻌﯿﺖ اوﻟﯿﻪ ﺧﻮاﻫﺪ ﺑﻮد. ﭘﺲ از ﺧﺮاﺑﯽ ﻣﺠﺪد ﺳﯿﺴﺘﻢ، دوﺑﺎره ﺗﻌﻤﯿﺮ ﺷﺪه و ﺑﺎ ﻃﻮل ﻋﻤﺮ ﺑﻪ ﻃﻮر ﺗﺼﺎدﻓﯽ ﮐﻤﺘﺮ از ﻃﻮل ﻋﻤﺮ ﻗﺒﻞ ﺷﺮوع ﺑﻪ ﮐﺎر ﻣﯽ ﮐﻨﺪ. در ﻧﻬﺎﯾﺖ ﭘﺲ از ﺧﺮاﺑﯽ ﻣﺠﺪد ﺳﯿﺴﺘﻢ، ﺑﺮرﺳﯽ ﻣﯽ ﮔﺮدد ﮐﻪ آﯾﺎ ﺑﺎﯾﺴﺘﯽ ﺳﯿﺴﺘﻢ اﺳﻘﺎط ﺷﺪه ﯾﺎ ﺑﻄﻮر اﺳﺎﺳﯽ ﺗﻌﻤﯿﺮ ﮔﺮدد. در ﺣﯿﻦ ﮐﺎرﮐﺮد ﺳﯿﺴﺘﻢ ﻣﯽ ﺗﻮان از روش ﻫﺎي ﻧﮕﻬﺪاري و ﺗﻌﻤﯿﺮات ﭘﯿﺸﮕﯿﺮاﻧﻪ ﺟﻬﺖ اﻓﺰاﯾﺶ ﻃﻮل ﻋﻤﺮ ﺳﯿﺴﺘﻢ ﺑﻬﺮه ﺑﺮد. ﭼﻮن اﯾﻦ اﻗﺪاﻣﺎت ﻫﺰﯾﻨﻪ ﺑﺮ ﺑﻮده، در اﯾﻦ ﻣﻘﺎﻟﻪ ﺑﻪ اراﺋﻪ روﺷﯽ ﺑﺮاي ﺑﻬﯿﻨﻪ ﺳﺎزي ﻫﺰﯾﻨﻪ ﻧﮕﻬﺪاري و ﺗﻌﻤﯿﺮ ﭘﯿﺸﮕﯿﺮاﻧﻪ ﭘﺮداﺧﺘﻪ ﻣﯽ ﺷﻮد. ﺳﭙﺲ ﺑﺎ اراﺋﻪ ﻣﺜﺎﻟﯽ ﮐﺎرﺑﺮدﻫﺎي اﯾﻦ روش در ﺳﯿﺴﺘﻢ ﻫﺎﯾﯽ ﺑﺎ ﺗﻮزﯾﻊ ﻫﺎي ﻣﺨﺘﻠﻒ آﻣﺎري ﻧﺸﺎن داده ﻣﯽ ﺷﻮد.

In this paper, we study the maintenance method in a system. We also consider a system that begin at time zero with most efficienty. After the first failure it is repaired, but we assume that the lifetime of the system is stochastically less than its lifetime at time zero. It is repaired after the second failure and after the third failur it is checked whether the system should be dismanteld or completly repaired. During the performance of the system preventive maintenance could be used to increase the lifetime of the system. Because these actions are costly, we discuss a method for optimizing the cost of preventive maintenance. Finally, we provide some illustrative examples.