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Look at the Arrival Table option on Source.

Hello, I'm creating a model with different entities, and I want each entity to follow its own rate table. I created the Data Table (called "PatientData") that lists several properties such as mix, service times, priority, and Rate Table. I also created the 8 Rate tables (1 for each type of entity) and entered each one on the Data Table under the Rate Table column accordingly. On my main source, I set the relevant properties as follows: Entity Arrival Logic Entity Type: PatientData.PatientType Arrival Mode: Time Varying Arrival Rate Rate Table: PatientData.RateTable Rate Scale Factor: 1.0 Entities per arrival: 1 When I run the model, I get an Error at 0:00 with the following information: Item: Source'MainEntr' Item Property: Rate Table A runtime error was detected at time 0.0 hours. Error evaluating the value of property 'Rate Table'. Invalid data table reference PatientData. There might be a really easy fix, but I can't seem to find what I'm doing wrong. I was following the same way I'm used to calling columns from table. Thanks for the help!

I am not sure I am reading this correctly, but it sounds like you want each of your hundred+ entities to be generated on its own arrival stream. In the Simio library, the Source is the only object/method for generating arrival streams. While the Source can certainly generate multiple entity types from one arrival stream, each source can have only 1 arrival stream You will either need to use multiple Sources or at least take a process approach with a Timer behind each arrival stream.

One way to do this is to use an Arrival Type of Arrival Table.

The Source's 'Time Varying Arrival Rate' Arrival Mode uses the Rate Table to specify the average number of arrivals per hour (or time period). As noted in the Rate Tables and Source - Discussion and Examples help, the rate tables use a non-stationary Exponential distribution to calculate the rate based on the rate specified in the table - therefore, some hours you may get 20 entities, while other hours you may get 21 and others 18, etc.

Define “processed batch” add-on process trigger at the Workstation. The process should include seize “worker”, move “to a specified node”. Define another add-on process at the specified node. It should be “entered”. In that process use release “worker” step, “consume” step for destroying the batched materials (the logic is like destroying an entity. Since we use material instead of entities we should use consume for this purpose). Then, at the end of the simulation collect related statistics to your purposes. For example, total distance the worker traveled. Note that, since the arrival and departure distances to Workstation are equal half of the total distance the worker traveled is the distance bathced materials traveled. And you can simply collect other statistics (I do not know what are they) by using somewhat the same logic.

you can simply use material quantities instead of creating huge number of new new entities (avoid using create, it is not suitable for your problem. you should think each product type as if they are materials, define material element type colum in your arrival table. You can benefit from autocreate property since you have much more product type). By this way you not only satisfy the current number of entity limits of the simio but also simplify the logic of your model. Just use material, produce required number of materials then increase the number of quantity available. While separating them or batching just simply use Workstation and BOM structure. The prosed logic needs to be adapted to your problem... In summary you should think a bit different...

Attached is V5 of the Crane Library. This version was developed in Simio 6.97. The new features in this version are: - Cranes now have a home node and an initial node. This enables the crane to be positioned at a different location at the start of the simulation run than the location where it resides when the crane is idle. - Cranes now have a home bridge that is different from the associated bridge. The associated bridge is used with the crane is initialized. The home bridge is the bridge where the crane resides when the crane is idle. - The Math.EPSILON delay is no longer needed for the first entity arrival. - Additional bay symbol. By default, the bay uses a symbol that is opaque (grey). If symbol index 1 is used (e.g. Current Symbol Index = 1 on the bay), the bay is transparent. The transparent bay is helpful if you wish to see schematics placed on the floor of the model. Additional, the following Simio V6 features has enhance our ability to model cranes. - You are able to turn off the Entity Instances at runtime. This is an option under the “Visibility” tab. With this option turned-off, the entity instances (including transporters) used to configure the model during design time, will not be shown when the model is run. - Entities now have a property for “Dynamic Label Text” under the “Animation” property group. This property enables a string expression to be added to any entity that will be shown during runtime. In the example, we are showing the current entity riding on the crane. The expression is “Math.If (Crane.RideStation.Contents.NumberWaiting > 0, Crane.RideStation.Contents.LastItem.ModelEntity.Name, "Nothing")” Note the following file is obsolete and has been updated in later posts below. (7/24/14)

I can catch you on skype to show you for I have various timers performing different things.... One example would be where I have priority based maintenance...i.e...Shutdown...Planned...Breakdown....each running off of their respective timers...As these activities timers can overlap as they form part of their own unique distributions, events are fired based on the priority constraint to allocate the transporter a different state...The logic involves correctly disposing of the tokens in a wait state of the previous constraint process as well as resetting and adjusting the timers....i.e....If I am on breakdown and scheduled maintenance hits, then the schedule maintenance process is executed and Breakdown processes stopped or delayed until a corresponding event is fired....this includes material handling assignments, crew, etc.... Another example would be dynamic generation of "demand" transporters based on a varying monthly rate dictated by variations in supply due to statistical randomly generated constraints... The timer is adjusted based on a change in arrival rate which is calculated and dynamically updated to ensure that there is always just enough demand for current available supply...This forms part of optimized planning for bulk carriers which cost a hell of a lot of money if they are just chilling in the ocean... But ultimately and perhaps the crown jewel is handling flow transfers from one transporter to another...since i had developed the logic before this super awesome new release of the transporter library, I needed events to check when the load or discharge level had been reached, or the full or empty state of the flowcontainer had been reached on either transporter, or objects fired events which needed to seize loading/discharging and stay, or seize loading/discharging and move away, as well as handle inherent timers on the transporter for breakdowns that will execute different processes depending on the type of breakdown....i.e. move the transporter or stay put... It all sounds really complex but its very simple.... Hit me up on skype...

I updated the library in the above post. This version is "CraneLibraryV4a.zip". In this version, I fixed both issues. 1) There needs to be a Math.EPSILON delay on first entity arrival to provide time for crane initialize. Update your source and add a "Math.EPSILON" delay to the TimeOffset property. This will provide enough time for the crane to initialize. I added a warning message to the library if there is a reservation request for the crane and the crane is not done initializing. 2) The library was assuming that a Transportation Node was defined on the bay. In your bay, the Transportation Node was NULL. I updated the library so the Transportation Node property can be NULL.

Hello, i want to model time varying arrival rates for my entities. If I choose rate tables I can't select random arrival rates. Is there any possibility to do so? Regards Nadine

Basically, I want to know how SIMIO creates the time between entity arrivals. Does SIMIO create all the times at once or the program does it dynamically (one at a time)? My problem is that I'm using the Arrival mode "Time Varying Arrival Rate" and for every day of simulation I want to change the "rate scale factor". If I do this with a state variable it doesn't work. For explample, if on day 1 I have a rate scale factor equal to 1 and on day 2 it's equal to 100, in day 2 the times between arrivals don't change at all.

Time varying arrival rates are random. Excerpt from Simio Help: Rate Tables The Rate Tables panel in the Data window allows the user to model situations where an arrival/event rate varies discretely over time. The number of fixed rate periods and the length of each rate period can be specified in the Rate table. The rate pattern automatically repeats during the running of the simulation. A Rate table is used by the Source object / Timer element to generate entities / events with a time-varying rate. Internally, a non-stationary Exponential distribution is used to calculate the rates. The rate units for the Poisson arrival process is Arrivals per Hour, regardless of the time units specified for the intervals of the rate table. In order to use a Rate Table with the standard Source object, set the Arrival Mode property in the Source to 'Time Varying Arrival Rate' and then select the appropriate Rate Table for the Rate Table property. The Source also includes a Rate Scale Factor property that can be used to easily modify the values within the table by a given factor instead of changing the values separately. For example, to increase the Rate Table values by 50%, simply specify the Rate Scale Factor within the Source to '1.5'.

I'm not sure about the answer to your question, although I believe it dynamically creates the times. However, I WAS able to change the factor on the time varying arrival rate... the attached model uses an arrival rate of 60/hour for the first hour, then i change the rate factor to 1/60 so it will have a rate of 1/hour. This drastic difference is immediately noticeable. Is this what you were trying to do? testRateFactors.spfx

Tried free eval version of Csim20, the included console M/M/1 demo. CPU-time reported is 2.5 secs (same computer) for 1M jobs. A bit faster than the Javasim. Csim obviously does book-keeping of all arrival/departure times to show queueing averages, but this can be turned off, which is what I now want to do in SIMIO. Turn on statistics only for specified objects.

A common way to create object definitions in Simio is by combining other objects, for example combining machines and a robot to define a work cell object. This type of object is called a composed object because we create this object by combining two or more component objects. This object building approach is fully hierarchical, i.e. a composed object can be used as a component object in building higher level objects. A second, more basic method for creating objects in Simio is by defining the logical processes that alter their state in response to events. For example, a machine object might be built by defining the processes that alter the machine state as events occur such as part arrival, tool breakdown, etc. This type of modeling is similar to the process modeling done in traditional modeling systems in use today such as Arena or GPSS. An object that is defined by describing its native processes is called a base object. A base object can in turn be used as a component object for building higher level objects. The final method for building objects in Simio is based on the concept of inheritance. In this case we create an object from an existing object by overriding (i.e. replacing) one or more processes within the object, or adding additional processes to extend its behavior. In other words we start with an object that is almost what we want, and then we modify and extend it as necessary to make it serve our own purpose. For example we might build a specialized drill object from a generalized machine object by adding additional processes to handle the failure and replacement of the drill bit. An object that is built in this way is referred to as a derived object because it is sub-classed from an existing object. Regardless which method is used to create an object, once created it is used in exactly the same way. An object can be instantiated any number of times into a model. You simply select the object of interest and place it (instantiate it) into your model.