 Such real-time extensions are usually very expressive and often lead to logics with undecidable decision problems. A way to regain decidability is to relax “punctuality” requirements involving precise time durations, by requirements involving time intervals. For details, see e.g. Koymans (1990); Alur and Henzinger (1992; 1993; 1994) as well as Reynolds (2010; 2014) on the real-time linear temporal logic RTL, and the survey Konur (2013).