Architecting and designing : Business Process Analysis (BPA) : Simulation of Process Models : Simulation tutorials : Simulation of BPMN Business Process Flows : Steps to build model : 5. Specifying details of the Start event
  
5. Specifying details of the Start event
1 Open the definition of the Start event, go to the Sim Definition tab, and specify that the event is a Start event in the BPMN Event Type property.
Click Apply Button to Change Property Set in Dialog
2 Click the Apply button in the lower right-hand corner of the dialog. This will save changes to the definition to the repository, registering it as a Start event, and add new properties and tabs to the dialog for a Start event.
Note Clicking Apply is the same as closing and reopening the definition – changes to the definition get added to the repository. What this means is that you do not have to click Apply every time you make a change to a type property if time is of the essence and you are not in the process of filling out all the simulation properties. If you are filling out simulation properties, you should establish a habit of clicking on the Apply button whenever you make changes to the type of any business process symbol. If in doubt, click Apply.
3 With the event now specified as a Start event, you will now have a property named Generated Objects on the Sim Event tab. Navigate to this property, and then click the Choices button. You will get a list of all UML objects that have been specified so far in the repository.
4 Select-and-drag the object Reservation into the Generated Objects property.
Generated Objects
We have just specified that when the Customer Requests Reservation event occurs, the object (or token) Reservation is created. We now must specify how often this object gets created – we must specify an Arrival Profile for the object.
Creating InterArrival Profiles
There are a lot of ways that we can specify the Arrival Profile for the Reservation object. We want to simulate the real world environment as much as possible. For example, we can break it up by morning, afternoon, and evening rates of Reservation call arrivals. In our example, we have done some statistical analysis, and found that the rate of customers asking for a reservation varies directly relational to 3-hour blocks of time during the 24-hour day, and during those time intervals, the rate of occurrence is fairly constant from day to day.
From midnight to 3am, there are on average 15 reservation calls
From 3am to 6am, there are on average 20 reservation calls
From 6am to 9am, there are on average 40 reservation calls
From 9am to noon, there are on average 45 reservation calls
From noon to 3pm, there are on average 30 reservation calls
From 3pm to 6pm, there are on average 20 reservation calls
From 6pm to 9pm, there are on average 40 reservation calls
From 9pm to midnight, there are on average 20 reservation calls
1 Create InterArrival Profiles for the object – with the Reservation object highlighted in the property, click Define to open the object Definition.
Click Define
2 Click the Sim Arrival Profiles tab of the Reservation object definition, and fill in the Arrival Profiles grid with the following Arrival Profiles:
Service Time Profile for Reservation
The Arrival Profiles created above correspond to the following time periods:
2400-259EST – midnight to 2:59am, Eastern Standard Time
300-559EST – 3am to 5:59am, Eastern Standard Time
600-859EST – 6am to 8:59am, Eastern Standard Time
900-1159EST – 9am to 11:59am, Eastern Standard Time
1200-1459EST – noon to 2:59pm, Eastern Standard Time
1500-1759EST – 3pm to 5:59pm, Eastern Standard Time
1800-2059EST – 6pm to 8:59pm, Eastern Standard Time
2100-2359EST – 9pm to 11:59pm, Eastern Standard Time
3 Click the 2400-259EST Arrival Profile, and then click the Define button.
Arrival Profiles
Note The information you put into the grid is reflected in the Arrival Profile’s definition, and can be adjusted in this definition as well.
Remember that this Arrival Profile is global to the repository – it is not specific to this Reservation object; it is being used by this Reservation object. It can be (re)used by any object in your simulations.
Next topic
6. Adding Service Time Profiles for each process
Parent topic
Steps to build model