某產(chǎn)品的壽命服從指數(shù)分布,對(duì)抽取的6個(gè)樣品共試驗(yàn)到2400h,沒有發(fā)生故障,則當(dāng)置信度為0.9,可靠度為0.8時(shí)的可靠度壽命下限()。提示:
A.1395.5h B.1495.5h C.1595.5h D.1695.5h
某機(jī)械設(shè)備在總工作時(shí)間2000h中發(fā)生5次故障,設(shè)其壽命服從指數(shù)分布,則當(dāng)可靠度為0.6時(shí),可靠壽命的點(diǎn)估計(jì)為()。提示:
A.504.33h B.404.33h C.304.33h D.204.33h
A.0.889 B.0.923 C.0.973 D.0.98