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Hello everyone, I am working on a project for class and am having difficulties assigning workers to specific servers depending on what day it is within the simulation. I have 18 workers and 16 servers. Each worker has their own 25 day schedule. On a given day, there is between 5 and 8 workers on shift and each worker needs to be assigned to 2 specific servers and no other worker should go to those servers on that day. However, due to the different schedules, a given worker will not always be assigned the same rooms they were assigned the previous day. Is it possible to assign each worker a specific server by day? Or is there another way that this might be possible? Thanks in advance for any suggestions!

Thank you for the quick and detailed response! I see the error I was making with work schedule and have tested it on one server, it seems to work as intended. Since each of my servers have a different capacity, would I need to create a unique work week and unique day type for them all? Or is there a quicker work around? The manual inputs for the date time are a great work around, I'm only modeling for a few years so I don't mind inputting a few dates. What I mean by there being no buffers is that no server can have a queue. I used a list for selecting the destination on the output node of each source (total of 8 ) where it's a hierarchy. It can go to a select number of servers and if all of them are full it goes to a dummy server of infinite capacity that exits the items to an overflow sink.

You want to make the servers have a Capacity Type of Schedule and follow the default Standard Week. If you don't want to give them a lunch break, just change the definition of the Standard Day. Leave the default Off Shift Rule of Suspend Processing. The easiest approach for arrivals is to have a Source with an Interarrival time of 4.33 weeks (or 4 weeks) and an integer random distribution for the Entities Per Arrival. Doing a "first Monday" is possible, but a bit complicated because Simio time does not have the concept of Month because months are of varying size. You could probably specify the initial Time Offset to be early in a month, then maybe make the interarrival time be something like DateTime.DaysInMonth(DateTime.Month(Timenow),DateTime.Year(TimeNow)) which would make the next arrival be exactly one month later (same day of the month). When you say you have no buffers, what do you mean? If an entity arrives when all servers are busy, should it be balked (possibly disposed) or should it wait somewhere like on the server input node, on a path or in the Source output node? If the above arrival approach isn't exact enough, you can put exact arrivals in a data table. The arrival time could be specified at any exact datetime you desire and still have the Entities Per Arrival be a distribution.

Hi all! I am simulating a facility with nearly 40 servers, each one starting with some entities in the input node at initialization and having a different capacity. Each server has a 0 input buffer capacity. My entity creation is currently set to having an interarrival time to be 4.33 weeks (1 month) with a random number of entities created. Currently, it runs 24/7 and does not care about the time, but I want to incorporate that. How can I make it so that the entities arrive once a month, let's say the first Monday, at 8am? How can I make it so the servers are only processing between 8am and 4pm Monday - Friday? The work schedule doesn't seem to work for me, but I could be doing it wrong, since I have a 0 input buffer, which I can't change as it's part of my routing logic for overflow. I would be happy with using timers or a process logic if someone can explain it to me. Ideally, the entities only arrive when it's during the working time, and the entities remaining after 4pm are just put on hold until 8am the next day. Thanks in advance!

Hi I've got a model where the situation is like this: 1. 3 Worker: W1 W2 W3 2. 3 Server: S1 S2 S3 On Monday (work schedule), W1 will work in S1 in the morning and work in S2 in the afternoon. W2 will work on S2 in the morning and S1 in the afternoon. But on Tuesday, W1 will work in S2 in the morning and S3 in the afternoon. W2 will work in S3 in the morning and S2 in the afternoon. The server properties in the secondary resource are "select from the node list." But since the node list for S1 and S2 contain both W1 and W2, and they both have the same hour of working (4+4), when the S1 server seized the resource on Tuesday morning, instead of W1, W2 got allocated instead( W2 should be in S3). I have tried: 1. Using server selection goal to " smallest distance," but it didn't work since the worker will keep swapping the room every day 2. Giving each worker a new initial value and setting the selection goal to "smallest value," but they still have the issue. 3. Try setting idle action for the worker to stay at the node, but sometimes the worker will go to the wrong destination from the first entity, hence no one working in the other room. (2 worker stay together) Is there any method to realize this idea? Thanks in advance

Hi Nicolas, I would investigate the Server property called Initial Capacity. This sets how many units of capacity are going to be available for the Server. You could also change this during the run by Assigning the Server's CurrentCapacity State Variable. I suggest checking out the SimBit titled "Worker Uses Work Schedule". You can access the SimBits in the Support ribbon in Simio. In this SimBit, I recommend changing the Initial Capacity for the Servers. You could set them to '6' or any value. When you run, you will see that the entities only move into the Process Station when they have successfully Seized the Secondary Resource. So even though there is 6 units available only 1 will be use when the Worker is able to process the entity. You can also experiment with giving the Worker a different Initial Number In System value so there can be more Workers. You will still see the same behavior; the number of entities that move into the Server for processing will be the number of Workers that were available to be seized. Happy Modeling! Liz

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 Guys, I have a source producing the entities, which is processed by the server with a worker. server and worker are assigned to work schedule (7Hrs) (12am-7am) arrival model of the server is set to time varying arrival rate. to control the source on holidays. But with current scenario the source is producing the entities on off-shift time. Please help out with a logic, so that source is produces the entities matching to the timings of work schedule. Note: Simulation run is for a period of 1 year. Regards, Alen

Hello, I have a model, that's producing parts (Multiple Parts A,B, C,D) with a server, sever works based on a work schedule and off shift days and holidays and the simulation is run for 1 year. Note: processing time for each part is different i need to extract the number of parts produced each month. Also need to determine the monthly efficiency of server , since some months may have holidays. Please provide a solution to get the dat on a monthly basis.

Double check that each Resource is hooked to the correct Work Schedule, and that you have the intended Day Pattern inputs for Mon - Sun in your Work Schedule(s). It sounds like you might need a separate (two total) Work Schedule for each group of 5 Resources. I would also recommend visually verifying that the Resources go OffShift (turn white) at the intended times. Other than that just make sure that the Off Shift Rule, in the Server's Secondary Resources, is also set to 'Suspend Processing'. Another way to check that the Server has suspended processing is to put some Dynamic Label Text on the Entity like 'ModelEntity.ID' so you can see exactly which Entity is in the Processing.Contents queue of the Server before and after the shift change. It should be the same one! Happy modeling!

Hello, I have selected Suspend Processing in the Off Shift Rule portion of my server modules but when I use a Status Label to indicate the Resource.Capacity.Utilized / Resource.Capacity, it appears as though the resources are not going off shift until after processing the entity in the server calling on the secondary resource. What else do I need to do? I'd like for the Resource to go off shift (and not finish the process) according to the Work Schedule assigned to it and then pick back up the processing of the entity when it gets back on shift. I've looked into several other posts but they seem to be outdated. Thanks!

Hello, I'm wondering if anyone has a good idea for how to view a resource's utilization according to the day of the week in the pivot grid of an experiment? Currently, my best idea is to just have a status plot in the facility window to illustrate this but I'd prefer to have an average utilization by day of resources in the pivot table. The scenario I'm working with is having "technician" resources that are being seized by server objects to do "maintenance" on the truck entities coming into the maintenance shop. I'd like to see which days of the week are the busiest so I could determine where to schedule new technicians. Any help is greatly appreciated. Thanks! Pit-To-Bay Off-Shift Rule Fixed.spfx

Simio offers user-defined work schedules in the Data tab. The SimBit ServerFollowsCapacitySchedule or others related to work schedules could be helpful. You can define a Pattern Based Work Schedule, to account for the shifts you described, and modify Server Properties like OffShiftRule (under Secondary Resources) to 'Finish Work Already Started' or 'Suspend Processing' depending on what makes sense for your Model. Adam 

Hi all, I met some questions in building the model. It seems a very general quesiton but I didn't find any solution from internet... I'm building a general workflow model. I want to decide the quantity of a server to optimize the workflow. I want to use experiments or optquest to get the 'best' number for each server. If I set the capacity type as Fixed, then I can set the initial capacity as ''referenced property'', then I can use this as control in experiments/optquest. However, I have a work schedule for each server now which means I couldn't set the capacity type as Fixed. And then I couldn't set capacity as ''referenced property''. I don't know how to control this capacity in my experiments/optquest. I know I can change the 'value'(which means the capacity) in workschedule table. But I can not change this number flexible in experiments... Or I don't know how to set this value as ''referenced property'' . Is there anyone who could help me with this? Thanks a lot!

I have multiple workers for different tasks and I want the workers to work according to different work schedules. When I use the work schedule option, all workers of one process use the same work schedule. In the examples they use different workers for each shift, but since workers come and go at different time during the day this would require a lot of different workers for each process.. For a server the capacity of the server can be changed during the simulation, is there a way to do the same for the amount of workers in the system? Or let each worker work according to their own custom work schedule imported from a table?

I'm trying to model airport ground operations using workers for the different processes, servers for the gates, entities for arriving airplanes and TransferNodes to control the flow of entities and workers. My research is focused on the control of these ground processes, but I can't get my process logic correct.. I attached a simple model to help answering the question. I want the workers to move to the right server before the entity arrives there and can immediately start processing the entities. One method is to use a global queue from which workers decide which entity to process next based on some criteria and dynamic rule selection. In the attached model I use two entities which go to Gate1 and Gate2. Gate 1 needs workers move to the node before it can start processing, Gate 2 does not. Using an add-on process, I move the worker to the gate before it is requested and wait for the entity to arrive. But for some reason it does not start processing immediately when the entity arrives and I can't figure out how to model this correctly.. It's the first time I'm using Simio, so I some help would be appreciated on how to set up the logic for my processes.. I'm kinda stuck now on how to get some basics thing in my model right or if I'm using the right processes steps.. Thanks in advance! TestModelWorkers.spfx

A worker may be assigned a work schedule similar to that of a server or vehicle. I would just leverage the default logic by throwing the worker into an Off shift State. There are numerous options as to how assign a work schedule. From your problem description, a Table Based Schedule may be more optimally suited.

I've got multiple workers going to single server. As the title implies, I'd like these workers to mimic the real-life behaviour of randomly going on leave for a random amount of time. Ideally I'm looking for something that's shown in vehicles or servers, but for workers. Does anyone here know an easy workaround for this? I did think about adding in a add-on process after the worker releases an entity with a counter, and after a certain count the worker is seized for a random amount of time. I just thought there would be a better way. Another alternative would be creating a work schedule for each worker, but there's over 60, so that might take a while.

Dear all, I am searching for a way to set the off shift rule for a server based on an entry in a data table. For the work schedule itself I have found several ways to relate it to a data table, but none for the corresponding off shift rule. Is there any?

Hello Ahmed, You still have your vehicles set to Network only. But there aren't any paths/networks to follow at all for it. It can't travel from one place to the other without them. Therefore, distance traveled is 0. You could place two nodes at each end of the server and have your vehicles move back and forth between those in free space. You'd have to set your vehicles' initial travelmode to Freespace Only. Next, you have some issues with your logic. Entities are trying to seize the resources/vehicle. You have your tasks set to seize SomeProperty.HasValue. The .HasValue only checks to see if there is a value in the property. Which it does. But the check is more like a Boolean. 1 or 0. It is not a value or quantity. Then you have the number of units of capacity for each vehicle only set to 1 because work schedule. Which is fine. But even if you take the .HasValue off, you are trying to seize more units of capacity than one. Since your vehicles never have that capacity (remember ride capacity and resource capacity are different things) your order will never finish processing and will always be behind. I would worry about the logic of your model. I have modified your model to over simplify things. Which I recommend doing first. Then building upon that. Get an entity to travel from the start to finish before adding lots of other factors in. In the modified model (saved in10.165) , you can see that you have set a Target. The Scheduled finish date versus the actual finish date are tied together. As far as constraints, you will see that in the Planning tab, after running the Create Plan button, there is under the Tasks of Section1 where the Constraints are shown. See image. In this case, it's the resource arrival of a vehicle. I hope this information helps. Thank you, Judy Model 1 Modified.spfx

Dear Judy, First of all thanks for your reply. Secondly, I attached to you another version of the model after I made some modifications. It can be seen in the model, I named a new server as Section 1 and added into it two tasks (Unloading and Leveling, they were servers in previous model) each has its resource (vehicle). I used only one entity for the two tasks. Section 1 will have total Quantity by 2031.25m3 (Which means the total amount of material, since a truck will unload this material and a grader will level it on the surface). The total length of this server (Section 1) is 200 meters as in real life. For the first resource "Aggregate Tipper Truck", its total number is NumAggTr = 20, its rate per hour is named as QSTTRate (has random value), its total number of trips to finish works is TTS = 113 and quantity in each trip is named as QSTT (has also random value). While for the other resource "Grader", its total number is NumGr = 2, its rate per hour is named as QSTGRate (has random value), its total number of trips to finish works is GTS = 32 and quantity in each trip is named as QSTG (has also random value). Since the previous expressions will increase with acceleration, so I inserted Level With Acceleration for each of them to be used as state variable into Finish (Sink). Finally, PPCQSTT and PPCQSTG are the productivity of each task. I have 5 inquiries and they are: 1- Why the resources did not make the appropriate distance travelling? For example, the number of "Aggregate Tipper Truck" is 20 and total number of trips are 113 so each should make about 6 trips (113/20), since the length of Section 1 is 200 meters, then each should make 1200 meters (200*6). 2- In table which named "Sub-Activity Schedule", if I change the value under "Scheduled Finish Date" column the value under Actual Finish Date will change. Why this occurred and why "Status" never be "Ahead" or "On Time"? 3- How can I calculate the values of PPCQSTT and PPCQSTG Daily or Weekly? 4- If I want to identify constraints into each task, how can I do that? 5- How can I apply the concept of Look-Ahead Planning (Daily or Weekly), to remove the added constraints? Thank you again Best regards, Ahmed Elkherbawy Model 1.spfx

Hello, I have a process Vehicle1_EnteredNode that moves a vehicle and seizes the two workers needed to operate. The two workers work from 8 to 12 and 13 to 17. When they are off the schedule, process AAInterruptCarMove is used to interrupt and release correctly the server and the vehicle. To make the Interrupt process, I’ve checked simbit VehicleStopsWhenServerOffshift. Then, I’ve used process AAInterruptGrutierEtAccrocheur to interrupt and release the two workers. The problem is, the two workers don’t get released. Instead, they go offshiftBusy which I don’t want because while OffshiftBusy, they are considered as being utilized. In that process, I've released the token associated with them but does not work. Any clue for me on how to get them released? I’ve put the model on this link : https://drive.google.com/open?id=1yZSFbqUlreh1v6oyG5Jy7AYzTrTBbBUS Thank you

Hello, In my SIMIO model there is a decision point and in this point some entities will be accepted and some of them will be rejected. For accepted entities, there are 3 different routes through the 3 different servers. So, I would like to create a rule in this decision point as follows: From 6am to 10am, entities would be accepted with probability (1-p1) and transferred to server A. So, entities would be rejected with probability p1. From 10am to 6pm, entities would be accepted with probability (1-p2) and transferred to server B. So, entities would be rejected with probability p2. From 6pm to 10pm, entities would be accepted with probability (1-p3) and transferred to server C. So, entities would be rejected with probability p3. So, I do not know how to determine the time schedule for link weight for each rout. I really appreciate if anyone can help me,