【单选题】职业卫生调查设计中,关于常用抽样方法特点的说法,错误的是()。
A.
等距抽样的缺点是总体有周期或增减趋势时,易产生偏性
【多选题】分层总和法的缺点是( )。
B.
附加应力计算通常使用查表的方法,查表时确定荷载变化边、基础长短边容易引起失误
C.
采用角点法分割荷载时繁琐,双线性内插法确定附加应力系数容易引起误差
D.
实际计算过程因人而异,缺乏严格的比较基础,计算结果的重复性差
E.
运用了平均附加应力系数α,给出了地基变形计算深度的简化公式
【简答题】C语言中的字符数组中的一个元素存放( )个字符
【判断题】字符数组由若干元素组成,每个元素中放一个字符,而字符指针变量中存放的是地址。
【简答题】阅读理解 Tom arrived at the bus station quite early for a Paris bus. The bus for Paris would not leave until five to twelve. He saw a lot of people waiting in the station. Some were standing in line, and ...
【简答题】阅读理解。 Tom arrived at the bus station quite early for Paris bus. The bus for Paris would not leave until five to twelve. He saw a lot of people waiting in the station. Some were standing in line, and o...
【单选题】( )的优点是仅须抽取一个,以后累加即可;缺点是当总体名册或个体单位数不完整时,无法采用;当遇到个体呈周期序列,又恰与抽样间隔相近时,抽样误差较大。