“number of person-days”的概念、定义、翻译、参考文献-科学参考

单词	number of person-days
释义	number of person-days Encyclopedia 工学膳食调查释 number of person-days人日数包括总人日数和个人人日数，是指以被调查对象的一日三餐为标准折合的用餐天数，将每人每日的三餐定义为一个人日。
随便看	metric plane metric-preserving metric problem metric projection metric property metric relation metric result metric scheme metric segment metric space metric standard equation metric straight line metric structure metric subspace metric system metric tensor metric tensor density metric theory metric theory of functions metric theory of numbers metric topology metric transfer metric transitivity metric type metric vector space

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