文章简单地介绍了B2010A龙门刨床继电器-接触器电气控制系统后,指出了电压负反馈带电流补偿的调速系统所存在的缺点,提出了用速度反馈控制的数字调速器来改造G-M控制系统的方法。文中详细地介绍了西门子SIMOREG DC MASTER6RA7075 6DV62-...文章简单地介绍了B2010A龙门刨床继电器-接触器电气控制系统后,指出了电压负反馈带电流补偿的调速系统所存在的缺点,提出了用速度反馈控制的数字调速器来改造G-M控制系统的方法。文中详细地介绍了西门子SIMOREG DC MASTER6RA7075 6DV62-0直流调速器各端子的连接。给出了组成传动系统的控制原理图,调速器相关参数的设置方法及设定值,由FANUC Oi MATER数控系统PMC控制的控制程序,以及控制系统的调试步骤。展开更多
Phase II clinical trials are commonly conducted as pilot studies to evaluate the efficacy and safety of the investigational drug in the targeted patient population with the disease or condition to be treated or preven...Phase II clinical trials are commonly conducted as pilot studies to evaluate the efficacy and safety of the investigational drug in the targeted patient population with the disease or condition to be treated or prevented.When designing such a trial considering efficacy conclusions,people natu-rally think as follows:if efficacy evidence is very strong,a go decision should be made;if efficacy evidence is very weak,a no-go decision should be made;if the efficacy evidence is neither strong nor weak,no decision can be made(inconclusive).The designs presented in this paper match this natural thinking process with go/no-go/inconclusive outcomes.Both two-/three-stage designs are developed with three outcomes.Additionally,a general approach based on conditional error function is implemented such that new decision boundaries can be calculated to handle mid-course sample size change which results in either‘over-running’or‘under-running’and ensure the control of overall type I error.A free open-source R package tsdf that calculates the proposed two-/three-stage designs is available on CRAN.展开更多
文摘文章简单地介绍了B2010A龙门刨床继电器-接触器电气控制系统后,指出了电压负反馈带电流补偿的调速系统所存在的缺点,提出了用速度反馈控制的数字调速器来改造G-M控制系统的方法。文中详细地介绍了西门子SIMOREG DC MASTER6RA7075 6DV62-0直流调速器各端子的连接。给出了组成传动系统的控制原理图,调速器相关参数的设置方法及设定值,由FANUC Oi MATER数控系统PMC控制的控制程序,以及控制系统的调试步骤。
文摘Phase II clinical trials are commonly conducted as pilot studies to evaluate the efficacy and safety of the investigational drug in the targeted patient population with the disease or condition to be treated or prevented.When designing such a trial considering efficacy conclusions,people natu-rally think as follows:if efficacy evidence is very strong,a go decision should be made;if efficacy evidence is very weak,a no-go decision should be made;if the efficacy evidence is neither strong nor weak,no decision can be made(inconclusive).The designs presented in this paper match this natural thinking process with go/no-go/inconclusive outcomes.Both two-/three-stage designs are developed with three outcomes.Additionally,a general approach based on conditional error function is implemented such that new decision boundaries can be calculated to handle mid-course sample size change which results in either‘over-running’or‘under-running’and ensure the control of overall type I error.A free open-source R package tsdf that calculates the proposed two-/three-stage designs is available on CRAN.
