A cohort of 1160 workers of a factory in Jianyang city was surveyed at base line and followed up in one year .

方法抽取简阳市某厂1160名职工为研究 对象，进行 基线 调查和一年后随访。

The bird resources of Youxi County were surveyed by using the method of mechanical dotting plot sampling and line transects .

在福建省 尤溪县采用机械布点、网格取样、逐格 调查的方法以县为总体进行了鸟类资源 调查。

Twenty seven turf samples in Nanjing city were surveyed with line intercept method for weed species during summer and the data obtained were analyzed with cluster analysis .

用样 线法 调查了南京市绿色草坪共27个样点的杂草发生及分布情况，并用系统聚类法分析比较了各草坪杂草群落的发生及分布特点。