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One option would be to have an arrival table, instead of fitting the data to a distribution - the arrival table would include the time that the arrival occurs (based on your table above) and then you would reference the arrival table from the Source using Arrival Mode == 'Arrival Table'. With an arrival table, you could also include an Arrival Time Deviation (Source - under Other Arrival Stream Options) property as a distribution, which would add some randomness to the arrival time. Another option is to use the Arrival Mode == 'Time Varying Arrival Rate' where you would specify a Rate Table (Data tab) that would include varying rates for different times of day. The interval size and number of intervals can be easily changed. The Rate (events per time period) would include the mean of an exponential distribution and would allow the rates to change hourly or every x hours. You may wish to review a few of the Sample SimBit Solutions (Support ribbon) under the Arrival Logic category of SimBits for more options.

Examine the attached file. In the model the customers are created according to the proportions of each customer group (i.e., the proportion of hotdrink customers will be 3/329 as you defined). You should note that max arrival property (under stopping condition section of source object) is set to 329. At the end of the simulation run the total number of hotdrink customers can be more or less than 3 due to the randomness. You had better run this simulation for more customers to get those proportions you mentioned. If I were you I run this model for 1 week or month etc. Each customer group follows their sequence accodingly. Sequences are defined in sequences table as well. Do not hesitate for more questions. customerspreadsimio.spfx

That sounds like you are doing a deterministic simulation. Depending on the form of your data you would need probably a single data file with columns something like: EntityType (you only need this if you have different types of entities) ArrivalTime - an exact time , either elapsed hours starting at 0 or an exact date-time MyServer (or Server Group) - Ideally this would be in the input node for the server (.e.g. Input@Server1) but if you have other forms you can make that work as well. ProcessingTime - a time (with units specified) --On the Source you would use Arrival Mode of Arrival Table, and specify Arrival Time Property as "MyTable.ArrivalTime". --If you have MyServer in the form of an input node, then in the output node of the source you would specify Specific Destination of "MyTable.MyServer". If you have it in another format, you might instead use selection weight on each path (e.g. if you just had an integer server number you might use "MyTable.MyServer==1" on the first path selection weight) --On the servers, set the Processing Time as "MyTable.ProcessingTime" That is the basics of how you might approach this problem. But I do have to question why you are doing a deterministic simulation. While deterministic analysis is useful for scheduling and validation, that approach is rarely appropriate in typical design models. You might reconsider if that approach is correct.

Hello, In my model I’ve made entity arrival mode to be On event and I’ve created an event named CommandeEvent in the Definition ==>event section. In order to action the event, I’ve created a process called ProcessEvent in which I have a decide step followed by a fire step that fire the CommandeEvent if the condition in the Decide step is respected. But when I run the model, the entities are not created. Is there something I should do differently or add ? Thank you, Flora

Hi Dave, Thank you for your quick response. Sorry for reply late. Let me simplified my question. Imagine in a taxi company, there are 100 taxi cars and 100 taxi drivers, each driver own his specific car, i.e. any driver can only use the car assigned to him and he cannot use the taxi car which belong to other drivers. The drivers will start their daily work at any time point from 6 am to 9 am, and that may be uniformly. After 8 or 9 hours working, the driver will drive his car back to the parking yard of the taxi company. What I want is to realize the situation that specific driver seize his specific car and then to release the taxi after 8 or 9 hours delay in Simio environment. In other words, driver 1 seize car 1 and release car 1, driver 2 seize car 2 and release car 2, and so on. Can I use a list or a table to arrange the drivers and cars? And I also want to watch the animation of car busy or idle by using resource object, and even consider the failure and repair conditions of cars. Clark

If you know WHEN you want entities to arrive in addition to WHAT (e.g. PartA at time 1.5, PartB at time 1.8, ...) then put that data in an Arrivals table (a normal table that has an arrival time column) and use the Source Arrival Mode of Arrival Table. If instead you want random arrival times with specified parts, use an approach like found in SelectEntityTypeFromTable but use a sequential row number instead of the RandomRow function.

Hi, I´m looking for a solution, that a source can create different entities (Part A, B and C) in a certain order (and then repeat it, not based on random). For Example: 1st Arrival Part A, 2nd Arrival Part B, 3rd Arrival Part C, 4th Arrival Part A (and so on). Is there an opportunity to realise this? I tried to use a data table, but probably I missed a necessary step. Thank you for helping. Chris

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

Add a 'NumberArrivals' data column to the data table that is defining the arrival schedule. For example, define your arrival schedule table like this: SomeArrivalTableName ArrivalTime NumberArrivals 8:00 am 5 8:30 am 5 9:00 am 10 9:30 am 8 etc. Then on the Source object, specify the Arrival Mode as 'Arrival Table'. Specify the Arrival Time Property as 'SomeArrivalTableName.ArrivalTime'. Specify the Arrival Events Per Time Slot as 'SomeArrivalTableName.NumberArrivals'. Note that you can also easily add columns in the data table as well for the Arrival Time Deviation and No-Show Probabilities, and then map those columns to the corresponding properties in the Source. For example, if the Arrival No-Show Probability actually differs depending on the day of week or period in the day.

I have an appointment time table that designates when arrivals occur. I would like the "Arrival Events Per Time Slot" to vary with time -- I've tried something like this: Math.If(((DateTime.Hour(TimeNow)>6)&&(DateTime.Hour(TimeNow)<=10)),1,2) (1 arrival between 6-10am, 2 arrivals any time after that), but it seems the arrival events per time slot is fixed at the time the simulation starts. When I start my simulation at 7am, I get 1 arrival/slot until the simulation ends at 6pm. If I start at 5am, I get 2 arrivals even between 6-10am. Are there any workarounds to this? Any suggestions would be much appreciated. Thanks!

I agree, it works when I use the expression on the "Entities Per Arrival" field. But it does not work for me when I enter the expression under "Other Arrival Stream Options > Arrival Events Per Time Slot" (where entities per arrival is set to 1). I'm using arrival events per time slot vs. entities per arrival because I am NOT looking for batch arrivals. I want multiple independent arrivals (each with their own realized arrival time deviations and no-show probabilities) per each time slot.

If you want a solution to a problem, it is best to post your questions inside Simio Insiders where we can post files with the response. I tried what I think you are doing and it worked fine for me, aside from the fact that the expression you used creates 1 arrival per event between 6-11am, 2 arrivals any time after that (because 10:59:59 has an hour that is still <= 10). I used your expression in the Entities Per Arrival property, created entities hourly on the half hour, and it produced 1 entity at a time until 11:30, when it produced 2.

It appears as if you are mixing the arrivals of entity types using two methods in the same Source. Typically, you would either randomly generate entities (using the first table, with referencing the Patient Types table, random row, etc. and then specifying the Entity Type as you have (PatientTypes.PatientType). OR, you would have an arrival table with the time of arrival and the specification of the entity type as you have in the ErrorApptTimes table. If you remove the entity key column from the ErrorApptTimes table and simply let the Patient Table determine the patient type, that would work. OR if you remove the table referencing upon entity creation in the source (to Patient Types table) and simply set the Entity Type to 'ErrorApptTimes.TableReference1' that would work. Just not the combination.

I am using arrival table to create my entities inside my simulation. So I am importing a column indicating the arrival time of all my entities; inside my data I also have property associated with each entity (exam type in an ultrasound clinic). I want to use that column as well and attache the associated property to each entity created. I am not sure how to do that. Also I want to use that property in another table and assign processing time distributions for each property (maybe defining the column as a key might help but I am not sure ). I appreciate any help.

Sources don't have associated workschedules for creating entities. There is an Arrival Mode property on the Source that allows entities to be created in different ways. Please see the SimBits (Support panel / Sample SimBit Solutions) named Appointment Arrivals or Source with Rate Table. One option would be to have a Resource with a workschedule that 'controls' the number of entities created in the Source, or the Entities Per Arrival property. To do this, you would create a state variable, let's say HowManyEntities. Within your source, set the Entities Per Arrival to 'HowManyEntities'. Set up the Resource with the workschedule for when you'd like entities to be generated and when not (i.e., so that when capacity is 1, you will change HowManyEntities = 1 and when capacity is 0, you will assign HowManyEntities = 0. Within the Processes window, you can have a process, Process1, that is triggered by 'Resource1.CapacityChanged'. Within that process, have a Decide step that checks the capacity and assigns the correct value for HowManyEntities. The Source then will generate entities using the Interarrival Time specified but based on the workschedule changes of Resource1.

I am having issues with having different entities arriving according to different arrival tables. With entities as foreign keys, I keep getting an error about rows being implicitly selected. Attached is my error message, entity types table and arrival table with entity types as a foreign key. I've also attached the properties I've set for my source. I am not able to attach my model here, but hope this makes sense.

I have the same issue -- would you be able to help? I tried using foreign keys but I keep getting an error that says: "cannot select row 1 of MixPercentage (column I use for generating the % of different entities) because row 1 has been implicitly selected by the ArrivalTable (table I use to specify arrival times for different entities)". Entities are my PKs. Any thoughts?

I’m representing an empty container deposit, where the containers are stored in different blocks. Gate in trucks arrives to the deposit loaded with containers that have to be unloaded by cranes and stored in the container blocks. In addition, there are gate out trucks that arrive to the deposit to retrieve containers. In the model, the containers are represented as entities, so as the trucks. I use Stations to represent the blocks that store the containers. To understand the logic of container arrival, we have to notice that next to the Station there is a Transfer Node, and when a container enters the Node (through a Transfer step in a Process), is transferred to the Station. To understand the logic of container retrieval, we have to notice that there is a Combiner next to the Station, and when the truck enters the Parent Input Combiner Node, a Process is triggered that searches for the container in the corresponding Station, and then it to the Member Input Combiner. Given that there is one Station for one block of containers, a single Station is used for the arrival and the retrieval of containers. The problem that I have is that in certain occasions, when a container is going to enter a Station, an error occurs and Simio shows this message: “The entity location is in transition state “WaintingToTransferIntoStation” and a new transfer request is invalid”. I don’t understand why this happens, given that in the Node that triggers the Process that executes the Transfer, only a single container enters at a time. Any help is greatly appreciated! Release: 8.136.13569 Model is attached. https://dl.dropboxusercontent.com/u/41163946/ModelPlacillaNewV3.spfx

How about using a state variable to count the amount of entities that have come out of your source and use another state variable in the source's Entities Per Arrival property? You can fire an event when the "count" state variable has reached a certain number that will assign the variable that you used for the Entities Per Arrival in an associated process to that same fired event. And when a new parent exits from the node of it's source you can check to see if the variable is set to 0. If it is, then assign it to 1 again. Judy

Set arrival mode of source on event then define your events to be either server is processing or there are three entities waiting in input buffer of the server. You should define a triggering event which is triggered by two seperate monitors each monitors the conditions you mentioned.

Sure. In a normal table using RandomRow or in an Arrivals table you can have a column representing the number of arrivals for that row. You could then reference that table row in the Entities Per Arrival property on Source.

Let me start by saying I have not used Simio in a few years, so any help is appreciated. I'm trying to model a busing operation with three stations and three buses. Each station will start with 1 bus. Passengers will arrive at station A, B, or C. Passengers at A might be going to B or C, and those going to C could ride the bus to B and stay on until the bus approaches C. It is also possible the bus could take a full load of passengers straight from A to C. There are 6 total routes possible: A-B, A-C, B-A, B-C, C-A, C-B. How can I set up my vehicle routing in a way that allows passengers to ride 1 or 2 segments to get to their final destination? (If someone needs to go from A to C, they could either ride from A->C or from A->B->C.) If a group of passengers bound for stations B and C arrive at station B, how do I make sure passengers bound for station C stay on the bus? I'm trying to use rate tables for my arrival data. Do I need to use 6 different rate tables and 6 different entities? One for each path? Thank you for your help!

Hi, I would like to create new entities once certain number of entities has left the system. Also, I want the simulation time to be reset. How can I do these two things? P.S. my entities arrive based on arrival table. Thanks, Manely

Hello All, I'm trying to create a model that will keep track of processing time for each transaction processed and reroute transactions that exceed a processing time threshold to an alternate sink. Initially, I attempted to rework the "Remove from Allocation Queue" Simbit, but the "Remove" process only seems to work with queues. The model itself is very simple. Single source with a random exponential inter-arrival time, single processor with capacity of 50 and 2 sinks; one for completed transactions and one for long running transactions which are manually routed. Any guidance you can provide would be greatly appreciated. Thank you, Ryan