Expected life time使用壽命;激光器使用壽命
expected life span預期壽命
sum of expected life預計年限總數折舊
expected life periods method使用期數比率法
Expected useful life估計運用年限
lose years expected life預期壽命喪失年限
depreciation-sum of expected life預計年限總數折舊
depreciation sum of expected life需計年限總數折舊;預計年限總數折舊
the expected life預期壽命