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Hi everyone: I am trying to simulate a BRT network which is composed by a set of buses (vehicles) that follow a sequence and schedules as well as some passengers (entities) who are generated by sources, transported by vehicles between bus stations (servers), and unloaded in sinks (acting as destinations). Those stations are connected by bus lanes (paths) that are restricted of overtaking maneuvers. If you check the model attached, in Case 1 (silver pool) the operation aforementioned is briefly modelled. However when the Vehicle 1 is boarding/alighting entities, Vehicle 2 must wait in the input buffer of each server until the vehicle that arrived before have finished its operations (as can be modelled in Case 2 (gold pool) if the bus is created as an entity rather than as a vehicle). I have been trying to fix this problem with an advanced option of the Vehicle' properties called "Can Transfer In & Out of Objects" (as can be seen in the image attached), that is good when a vehicle requires to be processed by a server as an entity. Nonetheless, in this scenario the passengers are not carried anymore by the vehicles which is not good. Could anyone help me with this issue? I will really appreciate your support because I am a new user of this great software . Kind regards, Alfredo Armijos. ServersQueueingVehicles.spfx

I am attempting to model the linked operations of a hospital emergency department and laboratory, but am getting suck on a few operational points. Patients come into the ED and are assessed a triage value (1-5) and depending on their value they get routed to different areas with different priorities using data and sequence tables. Also linked to those triage values is a probability that a testing order will be sent to the laboratory. If a test is requested, there are 4 main categories for testing available and their probabilities are also in the table related to each triage value, with an additional probability that the order is STAT priority. Based on the table data, I need to generate a specific order request that can be sent to the laboratory, which for simplicity is "generating" the specimens for testing, I'm using speed limits on the links to simulate specimen travel time for physical specimens vs the instant electronic request. I then need the lab to combine the completed tests and "fulfill" the request, sending back a results ready notice so the patient can be progressed. I would use 3 combiners for this except not every request will demand all 4 options so the combiners would sit and wait, ultimately generating fulfilled reports including all 4 tests. Is there a way I can generate a specific request, with properties to either run or not run 1-4 tests, collect the results and match the completed report back to the patient that it was generated for? The STAT priority flag adds a complication that I'm also unsure how best to represent the analyzer logic where STAT specimens abort all current testing in progress, put the batch tray back to the input buffer, test the STAT then resume. To handle the batch servers i am using the simple object made by dsturrock (http://www.simio.com/forums/viewtopic.php?f=17&t=737&p=2018#p1852) Thank you for any help you can provide, I've been stranded on this for a couple weeks now

It depends a lot on your objectives and desired level of detail. --Simplest: Bags are members, passengers are parents, they both show up at a Combiner object. --Better: I might model the carousel as a multi-stop circular conveyor and have entities representing bags come down the conveyer and entities representing customers come to the node to wait for their bags. I would attach an example, but we can only do so in the SI forums, not the public areas (due to spam attacks).

How can I create a Baggage Claim in a model? I've tried with a server where all passangers have to wait to the baggage, but i don't know if it is better to build a source or something like that thanks!

The recommended approach might vary by what you are waiting for. For example if the plane is a Vehicle that will come to pick up the passengers, then the easiest approach is probably to have a Server with 0 processing time. Entities will flow through it with no delay, but then wait in the outbound transfer node for the Ride requested. If you want to wait on something more arbitrary you could direct the entity that enters an outbound transfer node to Wait for an event. Then you would have to add some logic to Fire that event (unless it is one that is already automatically fired). You should post your questions inside the Simio Insider forum where we can post screenshots and examples to provide a more complete answer.

With several servers, entities only wait in one queue, while the rest of them are empty. How can I settle it to make them go to the emptiest ones? I thought it was by changing the outbound link rule of the output node from "shortest path" to "by link weight" but it's still not working. Thanks!

I assign a new state value after the entity leaves each server, and I need to keep those values. In a single run, I use the state observation log to track the value through the simulation. Is there a way to do that for an experiment? So I can repeat the run 100 times, and have the state value at each server for each run? Thank you!!

How can I creat a waiting area, where all entities will wait until they're processed? For example, in an airport terminal, after the secutiry control, they have to wait until the plane is ready to board And is there any way to set a maximun wite time in that area? Thanks!

HI all! I have a question which I could not handle it! I want to send a worker to do job in server 1, by finishing in server 1, it must go to server2 to do process and then go to server 3 and does its dut. then it must come back to server 1 and wait for starting new process ( worker transfers between servers while entity is moving forward). why it goes back to server1 before going directly to server3 ? for 2 servers, assigning the worker si so simple but for more than 2 servers needs more complicated logics. Please help me if you have any idea about it. model uploaded: https://www.facebook.com/download/372463152963464/WRKER%20REZA.spfx

Hi everyone, I've tried and checked the manual, it seems we cannot get access to the values in rate tables? Basically what I want to do is to do some planning ahead of time by reading and summing the rate data in it. Is the only solution to keep a same regular data table synchronized with the rate tables? The reason of using Rate Table is because it has a build-in function of calculating delay times regarding different rate zones, which is more realistic.

I am trying to model a system that has ships arriving to 1 of 8 berths. A ship stays in the same berth for 10 days and does not move, but instead different crews (resources) come to the ship at different times in the following order: Day 1 - unload crew Day 3 - fuel crew Day 5 - load crew Day 9 - catering crew Each type of work is performed by a different type of crew which rotate through the ships in the order they arrive to their berth. There is a chance that the crew will not complete all of their work in their assigned duration. At the end of each scheduled interval, if a crew has not completed all their assigned work, part of that crew will finish their work the next day, reducing the size of the crew to work on the next ship. For example: if at the end of Day 2, the Unload crew has not finished all their work on Ship1, on Day 3 a few of the unload crew will stay back and finish unloading Ship1 while the rest of the crew will move on to unload Ship2. Regardless of whether all the previous work was completed, fueling will begin on Day 3 as scheduled, so there could be more than 1 type of crew working on the same ship at a time. Additionally, as crews get better at their work, the day that a certain task begins may get moved up (i.e. fueling may start on Day2 instead of Day 3 after some period of time). At the end of Day 10, regardless if all the work was completed, the ship leaves the berth. I'm looking to see if anyone has some suggestions on how to approach this problem - entity staying in same place for a fixed duration while different crews come and leave in a certain order for a certain period of time.

Technically "Occurrences' is the number of times it changed to that particular state. So if it does 5 back-to-back transfers with no state change (like idle) in between, then that would be counted as a single occurrence. If you wanted to count each specific trip, then you might need to add a state on the vehicle or node.

Hello, I have created a sub-model with two servers connected by a path that will process n types of entities (i.e. different products that share a work station). In the main model these entities have a table reference assignment (specified at the source) that allows different processing times in each server in the model. If these entities enter the sub-model how can I allow for different processing times? Since there is no source in the sub-model I do not see a way to assign the a reference table (normally done in the source). Thank you for any ideas!

Hello, I am new to Simio and am having trouble with altering process times which differ according to the Model Entity. First, a little more about the background of the problem. I am trying to model a call center and have 12 different Model Entities that move through Free Space according to a sequence table. So for example, as part of the model I want a single server called "Sales" but there are three model entities that eventually end up at that server, but each is processed differently. Could anyone suggest a method to model this phenomena that doesn't involve adding additional servers? Thanks. Kevin

Here's a follow-on question I can't quite figure out ... I have a worker who is required as a resource to setup and teardown two different workstations. The worker is also a transporter to move entities from the source to the workstation, and from the workstation to the sink. The workstations are set to seize the worker for All But Specific, Processing, Move to Node, Input@Workstation#. The workstations have identical setup, processing, and teardown times (fixed at 5, 30, and 5 seconds respectively). The source initially starts with 2 entities, and then creates additional entities each time one of the workstations begins its Setting Up process. Once both workstations are processing, the worker goes back and gets the next two entities to place one into each workstation's input buffer. No matter what I attempt, I cannot make the worker stay at the workstation to complete the next entity's setup before taking the previous entity to the sink. Each time the worker takes the completed part to the sink and then returns to setup the workstation. Even though they happen at the same time, it appears that the previous entity enters the outbound node of the workstation and then makes a visit request to the worker, all before the next entity initiates the Setting Up process and attempts to seize the worker. To be more precise, the outbound part is placed on the outbound node, triggers the RiderWaiting event, requests and has accepted a transport request from the worker before the Teardown process has actually ended. I've read through multiple SimBits and other files from the forums. I can't get the next entity or workstation to seize the worker since the visit request has already been accepted or the workstation still has the worker seized to complete the teardown. I can't figure out how to use the Worker Used For Multiple Tasks SimBit since it only shows the worker going to and waiting at a node, and I need to model a workstation at this location instead of a node. I can't force a Delay math.epsilon on an Evaluating Seize/Transport process to force it to the end of the "same time", and putting in conditions (to reject transport requests if the allocation queue is not empty) appears to be moot since the Worker.AllocationQueue is technically empty when the RideVisitRequest is made (the next entity hasn't made the request yet). I also read in one of the posts that there is no way to reneg a ride/visit request once it is made, although seize requests can still be manipulated. I've attached an example file. It's definitely a work in process, so some of the custom processes aren't used or have been manipulated. I need to be able to model a real world process ... the worker would take out the previous part (teardown), set it down on a table (the output buffer), pick up the next part (from the input buffer), place it in the machine (setting up), and then press Cycle. Once complete, the previous part would be transported to the sink, and the worker would move to the next machine waiting. Thanks! Worker Seize vs Transport Test.spfx

Hi All, At the moment, I'm trying to model a warehouse. This warehouse consists of aisles: long sections of bi-directional paths, intermitted by basic nodes that represent picking locations. Workers walk through these aisles to pick orders. See also the attachment: the nodes are not visible but there are 20 nodes in every aisle. However, the bi-directional path does not enable workers to walk in two directions. It is possible for workers to encouter each other while traversing the aisle in opposite direction. This will create a blocking situation. I tried to solve it by using the 'Travel' step, such that the workers travel through 'free space' within a certain width around the warehouse network (setting 'avoind collision' to 'true). The problem however still exists. Is there a neat solution for this? It is a possibility to introduce all sort of extra bypass paths. However, this will make the model more complex and introduces walked distance biases. One of the purposes of this model is to compare theoretical picking times (based on walking straight through the aisle) with simulation. Adding extra bypass paths would violate therefore the purpose of the model. Thanks in advance for your suggestions! Wouter

1) Look at the SimBit EntityFollowsSequenceWithTable2, it is very close to what you want to do, including entity-specific processing times. If that is too much to digest in one SimBit, that SimBit is actually the 4th SimBit in a set of similarly named SimBits - work your way through them. 2) Look at the new features added in Sprint 119. This is another totally different way of implementing sequential and parallel activities.

Thank you for your answer. I've already looked deeply for sequences. I have two questions. (My model is attached for better comprehension). I'd like to add that this is a first part of my system, which is approximately 6 times bigger than this model. 1 - I was not able to make the sequence showed in the picture. In the model (Data window - SequenceTable - ProductC - Row 11) the next step should be M2 if the previous choice was M1 or M4 if the previous choice was M3. 2 - How can I define different processing times, since that the processing time in any machine will depend on which the entity is. For example, the processing time for entity A in M2 is 1,2 min while it is 2,1 min for the entity B. I did a table for it (Data window - Processing Times) but I couldn't reference it in the workstation's (M1-M6) properties. Thank you very much! FMS_part1.spfx

Sumanth - You have quite a few different ways to go about collecting these interval based statistics, the first few that come to mind include: (With Enterprise Edition) setup a daily timer and trigger a process to write the statistic to a output table, then reset the statistic Setup a tally statistic and a daily timer and trigger a process to tally the statistic, then reset the original statistic Setup a array and a daily timer and trigger a process to capture the statistic in the array, then reset the original statistic As you can see, in all cases have some statistic that can be cleared on the interval after capturing its data in either a output table, tally statistic or array. Let us know if we can be of any help with your healthcare model -- we've done quite a few of these with various levels of detail depending on the question at hand. Sincerely, Martin

If you look at the trace it shows you that the last thing that happens is the vehicle is waiting for its dwell time to end. Your vehicle is specified to Dwell Until Full - this applies at every node. You need to use the Dwell Only If property to specify which nodes where you want to wait for that condition. For example: Vehicle.CurrentNode==TransferNode1

Hello, i have some problems with my model and i really hope you can help me with that. I don't think it is too difficult but i don't know how to solve that. Please take a look at the attached model. So the goal of my attached model is that vehicles transport entities to the servers. The vehicles should wait till they are fully loaded with 4 entities but they are not allowed to have a length which is more than 12 meters. Each entity has a certain length. Every server has a random distributed processing time. As soon as the entity exits the server, a new entity is created. The vehicle should always pick up the next 4 entities. So my problems are: 1) The vehicle stops at Server 1 and i don't know why. But the vehicle delivers the first entity and then doesn't continue on his tour. 2) How can i measure how often the servers are idle? The problem is that the model needs to be changed after i get an entity to each server first. Because i want to measure how often the entities from the source arrive too late at the servers. But therefor each server should have one entity in their input buffer and one entity processing. Can is somehow start the simulation with two entities at each server? How can i realize that? 3) So length of each vehicle is not allowed to be over 12 meters when the vehicle picks up 4 entities. So in my opinion i should use the "Dwell only if" option. For example "StateVariable1<12" I wanted to use a state variable, so every time entity is loaded the length is add to that variable. But i don't know how to realize that. 4) I want to change the amount of the vehicles in the experiments. I did that with a property. Simio will just copy paste the same vehicle with the same abilities right? I hope you can help me with that. Thanks a lot! HeuristicTest.spfx

Just take a look somehere in help or documentation about Evaluating Transport Request, if token used in this process (so you have to search for tokens as well) is assigned value 0 or less, the entity trying to reserve transport on this vehicle is rejected and have to wait for another try. This is just a simple model, for production use (models with multiple locks) it make a good sense to use object approach as David showed in Elevator Simbit. That way you would be able to have logic in one place.

I want to monitor the time a server is idle as a response feature in an experiment. I think the standard Pivot Grid statistics has the "Time Starved" feature which tells me how long the server is idle. But i want the total idle time of all servers as a response in my experiment. So thought i may use a tally statistic with the value "Server1.Processing.Contents==0" but i don't know how to connect that with a property and i am not so sure if that is correct. I think that might be a common interest so maybe you have a solution for that.

Thank you gocken, but if the problem is not randomization seed, why do I get the same results for, say average or maximum waiting time, from every interactive run? For that specific example model, my intention was to show a single run could give different results for the waiting times but running an experiment with replications could give more reliable estimates.

After playing around the model g1h2j3 uploaded, I figured out that the problem is not the vehichle being an entity. The problem is the path directions. a) The problem is not related to vehicle because "Can transfer in & out of objects" property of the vehicle is false (or off). This means it is not allowed to transfer into sink object via its external node. b) the problem: The vehicle takes two the entities from two sources to deliver to the related sink objects. Due to path design, it has to pass over input@sink2 for two times (one while delivering entity (the green one) for sink2 and again one for coming from sink1 (after delivering the yellow one)) which causes two entity creation of source2 for one transfer. Solution: I redesigned the paths and it worked appropriately. see attached file... ExampleArrivalMode.spfx