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Please either attach a copy of the model you are referring to with this post or send the model with description of problem to support@simio.com. Thank you.

I have been utilizing SIMIO for a couple of months, but I am still relatively new to some of the features. One of the problems that I have recently encountered in my simulation is entities taking a path even when the receiving node (a separator) has an off shift rule. Specifically, I determine the availability of the separators based on 5 minute intervals with a TimeIndexedRow table reference. The attached image accurately represents my dilemma while simulating an airport checkpoint. The passengers are first processed in Server 1 and subsequently proceed into the paths leading to either separator 1 or separator 2, depending on which conveyor is available (has a value of 1) to process their luggage. In a specific scenario, lets assume separator 2 has a value of 0 meaning it is in the off shift position. When I simulate only one conveyor open, the passengers sometimes either take the inactive separator path and move back to server 1 to take the other route, or move back and forth the link until the separator becomes active again. Is there a way to block the path leading to that separator, for that 5-minute interval when separator 2 has a value of 0? Perhaps this could be done with an add-on process trigger, however I have not been able to formulate one. Any help will be greatly appreciated!

Hello everyone, i need some advice about how to make HQ videos in SIMIO. Is there any tutorial o something useful that i can watch or read? Please, i will highly appreciate that. Thank you...

Need some direction on creating mass load of entities. Attached is my file for version 10.174. Haven’t updated yet to 187. In the file I have two models: VIR_Workflow and CVOR. I’m trying to recreate what I did in VIR_Workflow where I imported a table of all the entities. It would be daunting to creating hundreds of individual entities. I want to do the same thing with CVOR however, it did not load to create the entities itself as I thought is capable of doing. There’s over 5000 entities for this model. I have also attached the CVS files I used to import data. Please advise the best way to load in pre-sets of data to create the entities instead of doing it manually. Or if there's something simpler in doing what I want to do please share. I think I missed some kind of step. SIMIO.zip

Thanks a lot for your quick reply, Dave. I will try your approach today. Meanwhile, I have acknowledged your recommendation and created a new thread in the Simio Insiders forum to allow for file attachments: Thanks again, Hristiyan

To start with, Destinations in Simio are always nodes. So the table should have a column of type Object Reference Property > Node. Although its not on the pull-down list, when you specify a entity destination as Select From List, you can also specify a table column of type node list and it will automatically respect the table rows associated with that entity. Model_RandomRow_FilteredTable.spfx

Yes, you can certainly model this in Simio, and can easily make it terminating. I would suggest reviewing any simulation textbook for verification and validation techniques. The general answer for number of replications is to run for a few (5-10?) replications and look at the half-width on your key output measures. If the HW is too wide, then run additional replications until all your key measures are at the precision you need.

Tricky problem. If you had posted this in a Simio Insiders forum instead of the public forum I could have replied with a model and figures. I would probably take the opposite approach - instead of adding additional "fake" machines, I would consider representing each workcell as a single server that makes use of associated resources for metrology, CNC, and airblast. I'd use Task Sequences to do the sequential processing of each part, then use the associated Loopback feature of Task Sequences to start over with the subsequent parts. There are a number of SimBits demonstrating task sequences. Unfortunately the only one demonstrating loopback (ServerUsingTaskSequencesWithDataTables_Loopback) uses data tables (which complicates things) but you might get the idea. Or you could do a similar approach with process logic steps. If you repost this in Simio Insiders you might get more help.

Hello, I am working on evacuation network design problem. My network has several evacuation areas (source nodes), road segment, and shelters (destination nodes). I consider congestion as people might stick in the traffic and they have to reduce their speed in the road. My goal is to send people from hazard areas to safe areas in the defined time horizon. So my first question is that, can I use SIMIO for simulating my model? Since my model has limited time for evacuation (Terminating problem), can I validate my problem with replications, if yes, how many replications I need? 2) Is there any other method to validate my model? Thanks,

Hi Allyson, thanks for you post. I will respond via Simio Support email as requested. Best H

To model shelves, I am trying to create a series of custom "Shelf" objects (subclass of servers) located in a grid pattern. I used a spreadsheet to automatically calculate the coordinate locations and generate a name (string) for each object based on its position within the grid. With just the Shelf object types in the spreadsheet, can bind the file to my object reference table no problem, import the data, and populate the facility window with my objects. That part works fine! Next, since I have an aisle running between the rows of objects, I wanted to set it up so that the objects all face "inwards", ie. the input and output nodes for the objects are facing the aisle. Originally I thought of rotating the Shelf object, but I ran into 2 issues: first, I discovered that I can't set the Shelf yaw orientation from the table, so that's not going to work. Second, I realized that even when I rotate the Shelf in the facility window, the nodes do not rotate with their parent object. I decided I would leave the Shelf in the same orientation as it is placed, but I would just re-locate the input/output nodes to the opposite edge of the Shelf objects on the far side of the aisle. For this I would need to make sure I can set locations for the input/output nodes in the same object reference table. When I added a row to the object reference table from within Simio (prior to binding to a spreadsheet), a drop down appeared, and I could select the input or output nodes for any object that already existed in the table, and then define the node's location in the cartesian coordinate columns. When creating a node this way, the node location is still relative to the object, ie. I can drag the object in the facility window and the node moves relative to the object, which is perfect. This input/output node creation and relative location definition via table is exactly what I am trying to automate, but this is where I started running into problems. In my spreadsheet I used formulas to generate names for the nodes to match the formatting of the input and output nodes in Simio (ex. "Input@..."/"Output@..."). I also added a formula to assign all input node object types to BasicNodes and all output nodes to TransferNodes and calculate the desired location coordinates for the nodes. The spreadsheet I made has the same format as the table in Simio where I tested manually creating and positioning the nodes. The issue is that when I bind the table and import the spreadsheet data to my model, the node names automatically change and are no longer formatted to reference the parent object. Because of this, these name-changed node objects are created in addition to the input and output nodes that are created for each Shelf object. However, if I remove the binding and add a new row, once again I can find the node name in the drop down list and assign the coordinates manually, and the input/output node that references the parent object will move to where I send it. My question is: how can I set the input/output node locations for the objects when creating objects from a table? There are over 500 Shelf objects in the table so I do not want to locate them manually, but the automated method is not working either. The only idea that I have is to make a new object "Shelf2" and define the external view to have the nodes on the opposite side, but that seems like a less-than-idea solution because then I would have 2 custom objects to update and maintain, that are otherwise identical. I am hoping that I don't have to do this hacky solution but I am interested to see if anyone else has dealt with this and has ideas. Thanks!

I have created a simio model with a big amount of conveyors and i would to change the desired speed of this conveyors while the simulation is running. Is it possible import data with the model is running and change the variable Desiredspeed associated the conveyors? Regards. Thanks you.

Thank you. I used another computer which doesn't have enterprise version simio to open it and it's helpful... I did't know 'Is.xxx' function...

Hi Sean, I would recommend exploring Time Paths. You can set a specific or random Travel Time on Time Paths. I don't know your scenario exactly, but you could have 3 different Time Paths linking ServerA and ServerB with Selection Weights referring to the specific Entity item number and each of these Time Paths could have a different Travel Time. All the best, Caleb Simio Technical Support

Hi Sean, Where is your Process triggered? Depending on its location, it may allow multiple Entities to Delay simultaneously. For example, if this Process is at Output@ServerA, this will allow multiple to Delay at once and the Entity that finishes the Delay step first will move along the Path to ServerB first. You can have them Delay one at a time if you change the Output Buffer Capacity to '1', however, this will cause ServerA to be in a blocked state until the Delay is complete. All the best, Caleb Simio Technical Support

Hi Mauricio, You can create a mock warm-up period by using an OnRunInitialized Process. An OnRunInitialized Process is executed when the model is first initialized. For example, you can use OnRunInitialized to Create and Transfer Entities into specific Servers as soon as the model is initialized, which is similar to what a warm-up period does. You can read more about OnRunInitialized in the Simio Reference Guide under the topic "Processes". While using OnRunInitialized can give you similar results to a warm-up period, it is not exactly the same as the Warm-up Period in the Experiments window. Keep in mind doing this will affect your Experiment and any other statistics collected (i.e. if you use a Warm-up Period in the Experiment it will essentially warm-up twice). A second option to explore is using a Timer to trigger a Process that contains a Clear Statistics step. This Timer should only go off once. This option is more similar to what a Warm-up Period in the Experiments window actually does. All the best, Caleb Simio Technical Support

Hi Sean, I would recommend exploring an Add-On Process Trigger that utilizes a Delay step. You can have the Delay Time of the Delay step set to an equation that is random (i.e. 'Random.Exponential(mean)'). All the best, Caleb Simio Technical Support

Hi, I am new to Simio. I was trying to add a routing decision in my model based on average time waiting at a server. But this function only shows up in the status label but not when I try to use it in the Processes as shown in the images. An entity reaching a node should choose the route to a server which has minimum average time waiting. What I am trying to achieve is to create a dynamic routing so that the average Time in System of the entity will be minimized. I don't know whether this is the right method or if we need to work with API or functions to achieve this. Any help would be much appreciated. Thank you in advance.

Hi, Thanks for the comments. Brief update, somehow I figured out I can do that by setting the transporter selection condition as "(ModelEntity.DestinationNode.AssociatedStation.CurrentCapacity - ModelEntity.DestinationNode.AssociatedObject.Server.InputBuffer.Content) > 0". Then, it will have the result as I want. However, one new issue comes up. When the worker pass a certain entity (let's say server A does not have capacity now, so the worker pass the product A, and goes to deal with other product. ), the passed entity will sit in the queue like forever. The worker will continue to move the new arrived entity, but will not touch the passed entity even the server A has the capacity later. What should I do to ask the worker go back to move the passed entity? I'm new to Simio. Thanks for the help. Best,

Jeff's solution is elegant and enough. Still, I liked the way you handled the problem via processes. You need not to define Stopcreatingentities event to fire. I revised your logic and attached its revised form as a png file (can not saved my changes due to having a different version of simio).

Dave had shared a post which, I think, can be a solution or at least a starting point to your problem. Here is the path to that solution: https://www.simio.com/forums/viewtopic.php?f=36&t=2334

To the best of my knowledge, optquest has no capability of optimizing string or boolen type controls. In the case of automatic optimization (which you want) it does not work! (i.e., It works automatically with only numerical values.). I do not understand why it can not but this is the way it optimizes so far. If you want to optimize string type controls you have to code your optimization routines (i.e., usually via metaheuristics) and integrate them with simio. For this to happen you should be somewhat an advanced user. If not you should ask for further help.

We will have 1 or more openings for an Industrial/Systems Engineering intern with our office at the National Institutes of Health (NIH) in Bethesda, MD. We are seeking a 3rd or 4th year undergrad industrial/systems engineering student with some experience with Simio and computer simulation concepts that you would have opportunity to apply in a federal government setting. Some background on what our office does at NIH: https://www.ors.od.nih.gov/OD/OQM/Pages/index.aspx The announcements will open on Monday, February, 4th and close on February 8th or when the applicant cut-off is reached – so please apply on Feb 4 if interested! Student Trainee (Administrative Support) – GS-0399-1/2/3/4/5/6/7: https://www.usajobs.gov/GetJob/ViewDetails/523190300 Student Trainee (Engineering) – GS-0899-1/2/3/4/5/6/7: https://www.usajobs.gov/GetJob/ViewDetails/522951000 If you have questions about the internship with our office, contact OQMCareers@mail.nih.gov

Hi everyone, I am working on a project that has more than 2,000 different arrival distributions. The distributions are all exponential, but they all change over time. To illustrate: suppose I am modeling 30 companies around the world, each company with a group of suppliers (or clients), each supplier (or client) with a group of parts (or orders) that will be arriving in my company to be processed. Each one of these parts coming from each supplier to each company (I will call it a combination) has its own distribution that changes over time. [this is an analogy to my problem] If I had only 1 company with a few suppliers and a few parts, the natural solution would be to use Rate Tables. This would be good because I want to investigate the impact of different Rate Scale Factors (increase or decrease of arrivals) on my key performance indicators. However, as I mentioned, I have more than 2,000 different distributions. So, my main question is: does anyone have a suggestion about how to create these arrivals in an efficient manner? I am assuming creating one source and one table for each possible combination would not be efficient, as it may make the model super heavy. I have thought about two different solutions (which I am not sure if it is good and, even worse, I do not know how to implement yet). So, recommendations to any materials, SimBits or tutorials that might provide more information about my ideas are really appreciated. #1) One idea was using an object inside an object in Simio. This may reduce at least a few combinations?! However, I do not know how to model objects inside objects in Simio. #2) Letting Simio auto-create all my servers and auto-fill the information using tables. This means that I would create one source for each combination. Although this may not be computationally efficient, at least I would not have to drag and drop each one of them. But again, I am new to this auto-create object tool and I do not know how to implement it. So, I really appreciate: - any ideas on how to solve my problem in an efficient way - materials that may teach me how to solve my problem using my idea #1 or #2. Another issue is that RateTables (as far as I know) cannot be imported and binded. So, how can I input all my 2,000 columns of arrival rate data in Simio? Otherwise, my solution #2 is really bad. I have also discussed the idea of grouping the arrivals together and using TableRowReferencing and discrete distributions ("mix") to reduce the number of possible combinations. However, the team I am working with does not think this is a good idea, since each distribution change over time in a different way. So, combining them may not be very accurate. Thanks!

Thanks so much! I didn't know you could do "if" statements, that really opens up my simio world! Thanks again for the timely reply.