I. Introduction
With the development of technology, automation has been applied in a wide variety of fields. In most safety-critical systems, such as power plants [1], aviation [2], and transportation [3], automation is applied. Automation has profoundly influenced human behaviors in human-machine systems. Following the application of automation in human-machine systems, the importance of humans is increasing as more and more accidents are related to human errors [4]. In several automated system transitions between human guidance and automated processes are possible, so takeover processes may occur. A reliable transition should be guaranteed to realize continuous and safe operation. For example, when driver assistance systems of a highly automated vehicle fail, the driver must take control to avoid an accident. A suitable level of human driver reliability is required in exactly that moment to handle a specific take-over situation. Human driver reliability may be affected by different take-over scenarios. It should be noted that continuous human operation could be also considered using similar approaches. From [5], it can be concluded that employing one common take-over request (TOR) time for all drivers and critical takeover situations is inappropriate.