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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, there is a simple approach you can use. Use Connectors between the queue server and the desks. At Buffer Logic of the Desks, change the Input Buffer Capacity to 0. Create a List with the Input nodes of the seven Desks. On the Output of the queue server change Entity Destination Type to Select From List and the goal to Smallest Value. Keep the default expression. It should work fine.

Hello everyone, I have a simple production line of 15 servers, some combiners, nothing too complicated. I need to somehow setup the input buffer at each server to have 1 entity at the start of the simulation and then run it. Or having filled servers with 1 entity at each server. Could anyone please help me and show me how to set it up? I need to start counting the stats once all the workstations are filled, but warmup period does not seem to work for that case, because it destroys the enitities at the servers and starts over. The filled-input-buffer-way looked to me like the easiest solution. But if there is another way, please let me know. Thank you!

My simulation is looking at maintaining inventory levels at multiple servers across a road network. Inventory is delivered via transports and is processed at each station at a rate of 1 item per hour (constant). What I am trying to do is to run some experiments to determine effects of different parameters on delivery system performance (ability to maintain inventory at (between 0-12) at each server location for the duration (72 hours is the current short test case). I have my responses set up to report Input@Server1.AssociatedStationLoad however the numbers are being listed between 0 and 1 instead of 0 and 12. Additionally, in the experiment output I get a 1 or 0 per server per scenario iteration. What I need to see is if any (and what) server hits 0 at any given time by having an output give an inventory level at current time for the duration of each run. Any advice?

This helped in some applications, especially use cases where multiple servers are in series and I need the operator to focus on the start or end of the process. Thanks! However, when servers are in parallel the operator tends to run back and forth between them. If I were to assign a higher priority to one line, the worker would focus on that line only. i.e. if he empties the que of parts in the input buffer of Server 1, he goes down to work on only 1 part at Server2 before going right back to Server1. Rather, I'd like for the operator to clear all parts in the que at Server1 before walking down to Server2 and vice-versa. I've tried doing this through process logic however I get stuck trying to evaluate which server the worker is supporting.

Thank you for the quick answer! Yes I know the ABC Costing Calculation in Simio, but I forgot to add, that I want to divide the total transport costs among the individual components that are transported at the same time. I think it would work with the calculation: TransportCostRate / TransportQty * TransportTime , so I just have to track the transport quantity for example with MyVehicle.RideStation.Contents. And my small model is just a example. My goal is to set up a cost analysis tool with calculation of transport costs, bufffer costs, processing costs, ... for finished production models. And for example the buffer costs, i want to use more specific cost rates (footprint dependence for example, ...) The disadvantage of my custom way is that so far I can determine the costs only at certain points (for example pick up and drop off) in time and not "continuously" as it is now with the automatic calculation. Or do you know if there is a way to adjust these "custom" times so that they are also calculated continuously?

Hi! I don't think you need to save those times stamps on MyVehicle. I would suggest you to use processes that triggers when the entity leaves the Output Buffer of the source and enters the Input Buffer of the server. To do that, create two process with the corresponding Triggering Event Name: Source1.OutputBuffer.Exited or Server1.InputBuffer.Entered, saving time stamps directly on the MyModelEntity.

I have a multiple combiners into which a single worker provides entities. While the worker is at a specific combiner, I want to check if that combiner's output buffer is full. I'd prefer not to create a separate process for each combiner as I have dozens. How do I code the process so that it is generic and that 1 process can work for any combiner? I'm hoping this is an easy question. Sorry if it's obvious. Thanks for your help.

Hello, I'm college student preparing the contest sponsored by "KOREA SOCIETY FOR SIMULATION". So I'm making model which has no input buffer , just remaining on the path. But the issue is that, if i set the input buffer as 0, the source makes entities only two, which is the sum of the sever's capacity.... I have seen that kind of model at the jsmith.co , but my model doesn't act like that.. What should I do for my model? isThereInputBufferCapa.spfx

Hey Simio insiders, I have been working on a model with workers. The workers transport goods over a facility, from one server to another. They seem to work perfectly until about 2 hours into the simulation. I have been looking into the the 'watch' properties, and it appears that the worker is waiting for something. This happens eventough i do not have a wait process in place. It waits at a server which it is about to drop an entity. The server input buffer is infinity, since i thought it might have caused the problem. Do any of you know why my worker is waiting?

How can I model where the robot always pick 2 parts and waits until 2 parts are available at output buffer of the server. (Robot is available in extras library). i have multiple servers in the model.

I have entity1 and entity2 entering a server. I want entity1 to have priority over entity2 when in the input buffer waiting to be processed no matter how many entities are already in the input buffer. I'm using connectors leading the entities into the server input node. Any suggestions?

Hello, I'm modeling an orange factory. One thing that I'm trying to solve is the modeling of the reception pools (of oranges). 1) Arrive trucks. 2) The truck is weight. Every truck have a random value of kilograms of oranges. (integer) 3) The truck dispose the oranges in a workstation. (workstation = reception pool). This is model with a Separator. 3.1) There are 3 workstation. 3.2) Every workstation has diferent Input Buffers. 3.3) The entity once entered in MemberOut@Separator1, it triggers a decide process. 3.3.1) This decide is to choose the workstation depending of the Quantity of Oranges versus the Input Buffer. Now I need to Wait until the Input Buffer is Empty, but I'm having problems with that, because the entities don't release from this server. If there are doubts about the model or anything else, I will answer as fast as possible. test1.spfx

Hi, I have a bottleneck at the end of my assembly line. I cannot dupplicate that station as my total number of workers is already high. Before hiring, I would like to try and reallocate and have satellite employees. I want to allocate my workers to that station when the input buffer has exceeded one entity. Every worker has to finish the entity they are presently working on at the other stations and the first workers that are done need to go the bottleneck station. The rest of the time, the workers can be allocated based on the smallest distance to the work stations. The bottleneck station usually requests 4 workers. That information is already set up in a table. When there is two entities in queue in that buffer, I want workers to be able to go finish the work and hence increase the processing time by X. I have tried a lot of different things, and all my data is stored in relational tables. Thanks!

Hi Amine, I have defined a new process named process1 which is triggered by Input@BUFFER_ST_1.Entered event. Then, I used interrupt step (in process 1) to get one entity from processing station whenever process 1 is triggered. Note that I set the processing time of BUFFER_ST_2 server to infinity to hold entitys until Input@BUFFER_ST_1.Entered event is occured. I am not sure if setting this to infinity is a problem?. Other than this everything is ok and it seems it works. Buffer varianti trazioni V2.spfx

Hello, I'm new to both the forum and the world of simio in general. I am trying to simulate how much the maximum buffer could be in 2 points of my process which are defined by the Buffer_ST1 and Buffer_ST2 servers. My problem is that I would like the Buffer_ST2 server based on a condition that would be every time an entity passes on Input @ Buffer_ST1, the Buffer_ST2 server releases only one processed entity and not all those inside the server as it happens now, I hope for being clear and thank you in advance. I put the model in the attachment Buffer varianti trazioni V2.spfx

I'm addressing a Multi Product Multi Routing situation. What's the best way to model a buffer without using the Server or WorkStation blocks? N machines are connected to M machines producing different products with alternative routing. Therefore, having a common buffer where entities coming from different machines could wait for the first available machine in any alternative route is very important. My question is whether this would perform better with stations or storages (or any other object in Simio). I intend to experiment on Buffer size to optimize space requirements. This would be done using experiments hence the chosen object/method needs to be suitable for that. Scheme: [n1] ___________ [m1] [n2] | | [m2] [n3] | Buffer | . . |___________| . . [M ] [N ] Thank you in advance

Yes, the buffer is set to 0 in the model distributed with the book. The book verbiage mentions that using Infinity for buffers will cause a tie in the selection logic, but we need to add some additional discussion about the differences between using values of 0, 1, 2, etc. for the buffer capacities.

I am trying to make a routing decision based on the Candidate node's routerequestqueue's summation of the entities user-defined property. If there are different types of entities with ex. different priority levels. I would like the routing process to choose the transfernode which has the smallest total sum of it's entities priority level. the transfernode that needs to be chosen also has a routing group attached to its entity destination type rule where its final machine has 0 buffer and due to a blocked destination rule, there will be a queue build up at the transfernode that needs to be chosen. I have thought about using a state variable for each node and using add-on process each time a unit enters and leaves a node but because the main model has many multiple nodes the node's entity priority sum has to be able to be accessed through the candidate.transfernode._________________. For example during the routing step in the process section, I have candidate.transfernode.destinationroutinggroupname.routerequestqueue which gives me the node's number of units waiting, but i need to be able to access the candidate nodes summed queued property. Is there either a way to directly access this information, have looked at the expressions and having a hard time finding something. failed attempt: candidate.transfernode.destinationroutinggroupname.routerequestqueue.population.defaultentity.priority.summation or is there a way to use the add-on process where i am adding/subtracting the priority levels, but somehow attach it to the candidate.transfernode's property Hopefully this makes sense. If you look at the file, please ignore the upper half and focus on the transfer nodes maintransfer, transfernode1 and transfernode1_1. maintransfer has an entered add-onprocess which is the subject of this question. the route process and it's selection expression is what I'm trying to adjust but find a way to express the candidate transfernodes of transfernode1 and transfernode1_1 (which are part of the XferRouting group). I'd like to choose and compare the total summed priority level of each node's queue. Simple_Routing.spfx

It seems the buffer capacity of the FinishedPitchFastStation is set to zero in the original file that comes with the book but was not explained in the book about this.

Hello, I want to bring a box in front of two server. I want the units in the box to be the entity for the two servers. How can I do that ???

I constructed a simple model with a single server where I used a rate table for arrivals. The server block capacity was fixed at 2. When I run this model by hand, I see that maximum holding time for the input buffer of the server is just about 24 minutes every time (but the same exact number), just as it would be if the arrival rate was constant throughout a 24-hour period. However, when I run an experiment where I defined the Server1.InputBuffer.Contents.MaximumTimeWaiting as the response variable, the result is 40 minutes for the scenario where the server capacity of 2 is 40 minutes.(I am using version 5.91) I am wondering 1) if I am confusing two different quantities (maybe the maximum holding time result is averaged by dividing by capacity, but that would be a bug, because the capacity should have no effect on the input buffer) or 2) if the randomization seed is the same for every run that I do by hand, which must be the case, because when I reduce the required replication count to 1 for the experiment, I get the same exact result for the single run that I do by hand. If that is the true reason, then I must ask where to change the randomization seed for every run.

Is there any way to clear output buffer of source at particular time of simulation (like every 165 th hour and its multiple)

Hello, I hope everybody is doing great! So I am trying to simulate a system that have different servers with different selection rules, all the customers wait in the same waiting area/queue. What I want is that all servers search in a global Input Buffer Queue (or Storage Queue) every time they are available and choose the entity based on their selection rule, or a process that send the entities to the their right destination whenever a server that can process them is available. I have attached a sample model less complicated than my system for what I want with further description of the objects, but it doesn't run properly at all, it is just for clarification. The first challenge is that I want the selection rules of the servers to choose from the global input buffer not the input buffer queue of their own, I am not sure how to do that or if it is applicable. The second challenge is that some servers have complicated selection rules (as shown in the sample model) I was able to represent these rules in a separate model by holding the entities at a node until the condition is met, but when I have multiple servers in some cases these entities can go to another server, so the rules conflicts with each others (unless we were able to integrate both rules together). Also, having multiple stations or storage queues with different ranking rules for each server do not work because when the entity enters the queue it will get stuck there even if another server was available and able to serve it. If you believe there is another way to represent the system with Simio I would appreciate your suggestions. Thank you for your time GlobalQueue.spfx