“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	Nonna Victorovna Mordyukova nonnegative non negative characteristic form non-negative characteristic form nonnegative characteristic form nonnegative combination nonnegative definite nonnegative definite kernel nonnegative definite matrix nonnegative definiteness nonnegative definite quadratic estimate non-negative definite quadratic estimator nonnegative divisor nonnegative element nonnegative function nonnegative integer nonnegative integral kernel nonnegative manifold nonnegative matrix non-negative matrix factorization nonnegative measure nonnegative number nonnegative operator nonnegative orthant nonnegative partial sum

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