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dido:public:ra:1.4_req:2_nonfunc:20_maintainability [2021/06/09 14:29] char |
dido:public:ra:1.4_req:2_nonfunc:20_maintainability [2021/07/26 16:13] (current) murphy [About] |
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| All these models are abstractions of reality; therefore, at best they are only approximations of reality. To the extent they provide useful insights, they are still very valuable. The more complicated the model, the more data necessary to develop precise estimations. The greater the extrapolation required for a prediction, the greater the imprecision. Also, obtaining all the data required as input to the models is difficult, time consuming, and may not even be very accurate. | All these models are abstractions of reality; therefore, at best they are only approximations of reality. To the extent they provide useful insights, they are still very valuable. The more complicated the model, the more data necessary to develop precise estimations. The greater the extrapolation required for a prediction, the greater the imprecision. Also, obtaining all the data required as input to the models is difficult, time consuming, and may not even be very accurate. | ||
| - | Measuring the [[dido:public:ra:xapend:xapend.a_glossary:m:mttr]], is also used as part of Availability (see [[dido:public:ra:1.4_req:2_nonfunc:14_reliability:02_availability]]). | + | Measuring the [[dido:public:ra:xapend:xapend.a_glossary:m:mttr]], is also used as part of [[dido:public:ra:xapend:xapend.a_glossary:a:availability|Availability]] (see [[dido:public:ra:1.4_req:2_nonfunc:14_reliability:02_availability]]). |
| The MTTR, identifies the average time to restore a system or component after experiencing a failure or breakdown in the expected (i.e., specified) operating conditions. The formula for MTTR is: | The MTTR, identifies the average time to restore a system or component after experiencing a failure or breakdown in the expected (i.e., specified) operating conditions. The formula for MTTR is: | ||
| - | : <color linen>o</color> <m format idiom size> | + | : <color white>o</color> <m format idiom size> |
| MTTR = {Total downtime (hours)} / {Number of failure events} | MTTR = {Total downtime (hours)} / {Number of failure events} | ||
| </m> \\ | </m> \\ | ||