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## Coventry University

Skip to 0 minutes and 9 seconds The first module that we should know about is the Create module. This module is used to generate temporary entities to be fed into the system. So, for example if we assume that this yellow box is a system which consists of a number of operations or processes then these entities will be fed into the system to test the performance of these operations, before they leave the system through the dispose module. So, if we link these two modules; the start and end modules, the create and dispose modules then we can see the flow of entities through the system. Let’s have a bit more idea about the Create module.

Skip to 0 minutes and 57 seconds The Create module consists of the name which can be changed to, for example, ‘Customers Arrival’. The time between arrival means the time between two consecutive customers. This is different than the arrival time. So, for example if we say the arrival time is 9 o’clock, the second arrival time

Skip to 1 minute and 25 seconds is 9:30 for the second passenger, then the time between these arrivals is 30 minutes. This is what simulation is concerned about, the time between arrivals. It could be fixed to saying every one hour we have one arrival. Maximum arrival is let’s set to 4 arrivals or entities. Or the time between two consecutive arrivals could be random due to other external factors and this randomness could be expressed by one of these expressions, random expressions. One of them is uniform. So, for example we will say the first customer would arrive between 2 and 4 hours. It means that the first arrival could be 3, could be 2, could be 2.5, could be 4. The second one could be different than this.

Skip to 2 minutes and 23 seconds To run the model, we can see the output of these arrivals. These random inter-arrival times could be visualised using the variable block. So, if we click on the variable block then we can copy and paste the expression, the random expression here. So, for example if the random expression is uniform between 2 and 4 hours this could be copied and then, once we open the variable expression box, we can paste it and hence we can visualize this random inter-arrival times, as we can see for every single temporary entity arriving at the system which is the yellow box, before the departure.

# The Create module

This module is referred to as the ‘birth’ node for temporary entities as it acts as the starting point in a simulation model.

Entities are created based on a time between arrivals. The entity type is specified in this module.

Typical uses include the start of a part’s production in a manufacturing line, a document’s arrival (eg order, check, application) into a business process, and a customer’s arrival at a service process (eg retail store, restaurant or information desk).