The universal program was worked out and operated on the first electrohydraulic controlledhead beam of support WS1. 7-210/450.
对国内引进的第一套WS1.7-210/450型电液控制液压支架的顶梁进行了实际运行。
2
Since there is a strong correlation between these variables and a country's wealth, they controlled for GNP per head by measuring whether it alone accounted for the difference in mating strategy.