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Hi, I have a production line with 2 sources. The arrival of entity A in source 1 triggers an arrival of entity B in source 2. Entity A and entity B then enter their respective servers for a processing time. Entity A is processed at table_openings between 10 and 15 minutes with probabilities whereas Entity B is processed at table_MF for 10 minutes. The process type is task sequence. Both Entity join at a combiner. Entity A is the parent and Entity B is the member. Afterwards, the combined entity continue along the production line. I have expected processing times for each task at each server. Before starting a task, a process starts where a state statistic registers the state processing time of the entity. I also put list state to verify the schedule utilization. I have verified visually and the state value for processing time is correct for every station while the simulation is running. What I have observed is that the state statistic average processing time for the servers before the combiner is the expected value, however, all the other stations are 10 minutes off. The simio output has the right processing times for all the stations after the combiner but not for the two stations before the combiner. Moreover, the list state average time busy value are ok for all the stations after the combiner but again the station before the combiner, it gives the total number of minutes it was busy. Also, if i do the average of the state log observation for each station in excel afterwards, I get all the correct processing times. I am guessing it has something to do with the combiner, but I am lost. How can the processing time for table_MF be 10,48 when the processing time is a fixed 10 minutes in the facility window? Why is the list State MF and OP different from all the other list states? Thank you for your help!

Hi, I have a problem in my simulation model. In my model, entities do not exit from the system after finishing the process and they will go to a virtual server and two random variables (exponential (10 hours), exponential (20 days)) should be run PARALLEL for each entity. Once running of a variable is done, the other variable should stop. Every entities with exponential 10 hours variable will come back again to the system, while other entity with exponential 10 days variable will exit the system permanently. Actually, the holding time in the virtual server should be determined based on the Min of two random variables. I tried to consider these two variable time as processing time in task sequence (same sequence number) for each entity in virtual server. The problem here is that I do not know which logic or method I should use such that if on variable stops first, the system automatically should be able to stop the other variable and select the path. I really appreciate it If anyone can help me. Farnaz,