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Cycle : (# do Loop: INNER Cycle;restart Loop; :Loop #);A Loop labelled imperative will execute thedescendant's imperatives and then re-run the Loop.A descendant of Cycle could make sure the loop doesnot last forever:TermCycle : Cycle (#Terminate : (# exit TRUE #);InnerAction : (# .. #);doInnerAction;(if Terminate then leave TermCycleif);#);A TermCycle instance will first call the do part ofCycle and after INNER is reached the do part ofTermCycle is activated. After the InnerAction is finished,Terminate function is asked whether a condition forleaving the loop is matched. If it is, the TermCycle haspassed so the Loop in the Cycle super pattern will not berestarted.In this case only a little or no work is saved forprogrammers if they use the Cycle pattern. Its advantageis however well arranged and unified approach to cyclingthrough various structures without the need of knowingthe details about what is done in the loop and what areterminating conditions.THE BETASIM FRAMEWORKThere is no support for building simulating models inthe Beta. But it is supporting coroutines with its quasiparallelsystem.The coroutines in the Beta are active objects, whichexecute their task and then may suspend. The suspensiondoes mean that the current coroutine is passing theapplication resources to another living coroutine and thenext coroutine is then attached to the program executionstack. When there is no other active coroutine waiting inthe queue the application will terminate. There is nosupport for suspension of a concrete coroutine whereas aconcrete coroutine may be attached.The BetaSim framework is an abstract layer, whichbrings the comfort of the Simula programming languageto simulation models building in the Beta. Thecoroutine's interface is enhanced using a new basic classthat has to have the interface of the process in Simula. Itdoes allow to be passivated, cancelled or put into awaiting state.When the new class supports the “suspension fromoutside”, so a coroutine A can send a message to suspendcoroutine B, it has then to support scheduling to behavelike in Simula. So methods like runAt, runBefore,runAfter have to be added to the framework somehow.A few other Simula capabilities are then added likedistribution functions for random numbers generating ormain process, current process, nextEv process, or lists ofprocesses to the framework to be completely ready forthe use.Of course the BetaSim build process is done alreadyso the programmer users don't have to do the coroutinesynchronisation and related implementation issuesthemselves and can build a discrete simulation model in aquite comfort manner:BetaSIM (#Loader: @|Entity(# ... doL: cycle (# ... #);PASSIVATE#)Discharger: @|Entity(# ... doL: cycle (# ... #);PASSIVATE#)CCar : Entity(#Distance, Velocity, LoadingTime,UnloadingTime: @integer;Init::< (# ... #)doL: cycle (# doLoadingQueue.into;(if Loader.getIdle thenLoader[]->run if);PASSIVATE;(Distance / Velocity)->HOLD;DischargingQueue.into;(if Discharger.getIdle thenDischarger[]->run if);PASSIVATE;(Distance / Velocity)->HOLD#)#)LoadingQueue: @WaitQueue (# #);DischargingQueue: @WaitQueue (# #);doAnnual Proceedings of Vidzeme University College “ICTE in Regional Development”, 2006122