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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!

Hello everyone, I have a server which can potentially have many entities waiting in the input queue. All these entities have different priorities (as a model entity state variable). I want to retrieve these values to then select the highest one and put it on a status label to track this during the run. Is there an option to do this? Regards, MF

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.

I have a project where I want to model aircraft moving around an area of a fake map. The only map options I've seen in simio are the ArcGIS World View and Street map under View -> Map View. I uploaded a picture as a symbol and set it as a layer, but when I do that certain areas of the map work and others don't. It's like the map area is 'too busy' and it automatically declutters, which in this case hides aircraft moving in certain areas of the map. I tried to zoom in on areas and the map works as advertised, but for demonstration purposes, I need to have all traffic on the map appear at all times (as if I had a map selected under map view). This wouldn't be a problem if I could set an image as a "background color." Any suggestions?

Hi , I have a system with a combiner, that combines different variations of batches. On exiting the combiner the crane picks the combined entity up and drops up at a server. Each of the different batches will have a different load and unload time. Is there a way to do this? Basically, does batch contain product ‘A’ if so crane time is ‘X Mins’ Does batch contain product ‘B’ if so crane time is ‘Y Mins’ Thanks for any help!

Hello all I am relatively new to Simio and DES. I am trying to model a pallet conveyor. It is a closed loop conveyor. I use the "vehicle" as the pallet that loops around the conveyor. At the source the part (default entity) is loaded on the pallet. At the sink the part is unloaded. The problem that I am encountering is that the vehicles from time to time pile up at the sink, then after a certain amount of time they continue back to the starting point "Source1". This happens more the more I increas the "initialnumber in system" of vehicles The transfer-in Time for the sink is set at 0. At the model trace I read this for the "Input@Sink1" : "the in Token waiting at VisitNode step for '1' other processes to complete." I would apreciate any advice. Many thanks! Vehicle_stuck_at_sink.spfx

Hi, A Separator is creating copies of the entities that enter it, the number of copies depends on a probability distribution, I want the worker to transport all the entities created from the same parent entity at once. Is this possible? I attach the model for better understanding. Thank you so much! Model.spfx

Hello everybody, I'm trying to make this work but I cant Type/Conteiner BinBig BinMed BinSmall Product1 1 1 - Product2 - 1 1 Product3 1 - 1 Product4 1 1 1 I want to make a node where these entities (Products and Bins) are convined in one batch, I try to use a process based in decitions and search.. the file is attached if you wanna take a look on it.. (the product have to be the parent) OptimoContenedores2.spfx

Hello there, this is my first post here and I hope someone can help me with my problem. I´m quite new to Simio and working on my first project. I have some "return entities" that are considered "bad" at the end of the production. So they will get collected in a server which is used as a storage and get returned to the factory every 24 hours, to get reworked, if there is capacity left. Now, I want to check if there is capacity left in the destinated server and in best case, reserve the needed capacity before, before I route these entities towards it. After the entity arrived in the server, the reserved capacity should get released again. I couldn´t find a good example here in the forum or via google search, as in the SimBits, how to solve this the correct way. Maybe someone here can give me a tip, how to. Thanks in advance. Aljonator

Hi! can you help me please? In my model I have a server that I want to function as storage, this server is linked to a combiner which will combine the member entities that leave the server with a parent entity that will arrive at it from another node. Each member entity has a state with a unique number linking it to a parent entity (there may be more than one member entity with the same state number). How can I extract from the server only the member entities whose state is equal to the state of the parent entity that arrives at the parentinput of the combiner? Thank you so much! 18.10.spfx

Hi! In my model I have entities called "Pedido" which have a state called "id_del_pedido" which is equal to the ID of the entity. These entities will enter a Separator that will create copies of the entity according to a probability distribution. Since the new entities are copies of the parent entity, they will have the same "id_del_pedido" status as the parent entity. Subsequently, the entities created will enter a Server that acts as a warehouse. This Server is linked to a Combiner, when the parent entity reaches the Combiner's parentinput I want only entities whose "id_del_pedido" is equal to the ID of the entity that reached the Combiner's parentinput to leave the server. This works perfectly in the first Server-Combiner set of my model, but, the Combiner's outputnode is attached to another Combiner and I want to repeat the same activity as in the first Combiner but I get an error that I don't know how to solve. I attach my model so that my problem is better understood. Thank you very much in advance! 18.10.spfx

I'm trying to initialize a model with over a 100,000 entities of the same type. However, when I do so, I get a warning "the number of active entities in the simulation has exceeded 20,000 objects". If I continue, Simio basically crashes after a few minutes. I tried to scale everything down by a factor of 1000, but then when I try to create entities in quantities < 1, it doesn't seem any entities get created. So my question is how do I balance out the need to have 100,000+ entities and the need to be able to create new ones on a much smaller scale (10s for example). Thanks in advance for any help with this.

Hi Indsiders, after 30 hours of simulation i get this error message from a DB Write Step: Exception from Step "StepName" execution.Object reference not set to an instance of an object. I dont know why i get this error, cause all entities before where able to execute this step. Is someone able to give me an adivise with this informations ? Beste regards, Benjamin

Hello, I have two concerns. In one of my small models I want my transporter to make a round and pick up the entities at the different locations and bring them to a destination (Server1). In addition, I would like that the individual times are measured with a state MyModelEntity.TmpStart and MyModelEntity.Duration, in order to calculate afterwards with a transport cost rate the cost for each individual part. Unfortunately I'm getting desperate with this and getting various error messages, does anyone know how to implement this? Best Regards, Gashi

First of all, Thank you so much for the answer in advance, but could I bother anyone who answers with some example model or picture of the method I am still new to SIMIO, so I am concerned about following the advice correctly. 1) Let's say every day I have X number of people arriving( using distribution to generate numbers outside SIMIO randomly). This is the shop where people visit from 8.00 to 20.00 every day with different visit rates per hour (example as below), and I use X to time to this percentage so I can get the exact number of visits per hour. The problem is I want to make an arrival interval random with some sort of function/distribution or table(excel calculation), not a stable arrival rate. My idea is random from 0 to 1 and gives the random number (Y) to match with X outside SIMIO and put the whole table in, but I wonder, is there any better method than this? 2) The second question is about two entities from different sources, A and B. A and B will go through the same server for three servers, but after server 3, one will go to 4, and one will go to 5. Can you give me any advice on how to do that

How can I schedule a randomly distributed death event for each entity, and pull them out of the system (or perhaps route to a "mortality" sink) if it occurs before they have already left? Somewhat similar to reneging, but I need mortality to be possible during a service, not only in queues. If an entity is removed from service, I also need the seized resources to be released. What I have tried so far: When an entity is created, I provide them with a state variable for TimeTillDeath, lets say exponential(2) hours. This is a real number, not a datetime. As they enter each queue, I set the reneg trigger as ModelEntity.TimeTillDeath subtract any elapsed time since creation, min 0. This works to model mortality while they are waiting for service, but not during a service. Any help is appreciated, KO

I have two transporters that have failure rates and associated downtimes. I am trying to create an output so that I can track the transport downtime (say Truck1[1] failed from Hour X to Hour Y) so that I can analyze the impacts of vehicle downtimes on the system. I don't know the best way to go about doing this: Add-on Process for Failure and for Repair but then Assigning what value to what State/Property/Table? This is where I am getting lost. Any help would be greatly appreciated.

Is it possible to specify the random stream used for the RandomRow function?

Hi all, I am building a simulation of a system with multiple separators which MemberOutput nodes two different routing policies can occur: 1. Standard Policy In the 'Standard Policy', each separator has its dedicated transporter assigned to it and entities arriving at the MemberOutputNode can only select the defined transporter. To this end, a DataTable has been constructed. 2. Power Hour policy In the 'Power Hour Policy', operations are shifted into a higher gear. We select a maximum number of three nearest transporters whose ride request is 0 and include them in the DataTable which specifies the Transporter Selection. Entities arriving at the MemberOutputNode can now request rides from any transporter in the DataTable. I tried to reference to a DataTable called 'TransporterSelection.EPT' in the Transport Logic of each MemberOutput Node. Each value in the EPT column is cross-referencing to a DataTable in which I try to assign the MemberInput Nodes as a Node Reference State Variable of the Transporter (EPT). Is there any way to dynamically assign more (or less for that matter) Transporters to a TransferNode? Hope that anyone knows how to do this! Cheers, Toon

Hello, I am writing my master thesis on production system design with simulation modeling. I have designed two models in Simio - one for current production system and one for optimized one. They are both designed in a correct way and they work as they are supposed to. The only difference between them is in path lengths. The difference between results from optimized and current system should be 3 - 5 % but for some reason I get all of the results identical to the last decimal place after running an experiment. I have attached a picture of my path properites and travel logic of entities. My guess is that for some reason path length is not being considered in the simulation. If anybody has any ideas what could be wrong, i would really appreciate your help.

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!

I know it's been a while, but I just came across this question and I'm responding in case this can help someone else. Depending on the problem, modeling nurses as patient capacity might not work; for example, if you need to limit both a nurse's active utilization and the nurse's patient load. Two general approaches exist: Easier: Create two different resources, rename one 'NursesActive' and the other 'NursesPassive.' Set the latter to have n times the capacity of the former, where n is the patient ratio at n:1. Require simultaneous seizure of one of each type of resource when first assigning the patient, and release them separately, re-seizing the former as needed. Harder: Subclass the Resource object and create states to track the patients assigned and a property to define the patient ratio. This approach enables more fine-tuning as necessary.

Hi, I want to generate one type of product with one interarrival time. I have one source and one model entity. However, this entity can have different lengths following probabilities. Depending on these properties, the processing times at the servers will be shorter or longer. I tried to assign a state to the entity before this entity exits the source so ModelEntity.Length becomes DataLength.prob.randomrow. where DataLength is a table with the different lengths and the probabilities associated with those Lengths. The only thing is that it is a property and not a state, but I do not know how to do it in another way. Afterwards, I have different processing times at the servers depending on the different characteristics of my entity. For example, server1 will have different processing times depending on the length. How can I reference to the good processing time say I have added a column to the table DataLength with the associated processingtimes according to the lengths? Finally, I would also like keep track of those different lengths generated and see what the model produced in the end. Thank you for your help, Emilie

Greetings, I would like to know if there is a way to include the volume of the entities into the vehicles capacities ? E.g. let's say that i have 5 entities with different volumes, and the vehicle has the capacity to transport X m^3, how can i include this in simio ? Best regards,

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!