[单项选择]This arrangement is () if the elements are directly connected to one another and the control action takes place without human involvement. A. a manual closed loop B. a manual opened loop C. an automatic closed loop D. an automatic opened loop
第34题: [单项选择]源皮距给角照射时,下述哪项条件基本不正确?() A. 体位正确,照射距离正确,射野面积正确,机头方位角正确 B. 体位正确,照射距离正确,射野面积正确,射野中心束对准体表野中心 C. 体位正确,照射距离正确,射野面积正确,大机给角正确 D. 体位正确,照射距离正确,射野面积正确,机头方位角正确大机给角正确 E. 体位正确,照射距离正确,射野面积正确,机头方位角正确大机给角正确治疗床 参考答案:E