Definition of Simulation Properties

When no shapes are selected on a diagram and a user selects “Properties” the Simulation Properties window opens and a user may configure simulation parameters.

Run Setup

Simulation Time

The maximum length of simulated time for which the simulation may run. The simulation may run for a shorter amount of time if there are no more cases to process.

Warmup Time

The amount of time for which statistics are not recorded at the start of a simulation.

Start Time

The date and time at which the simulation starts.

Random Number Seed

Controls the generation seed for random numbers that are created in the Simulation.

Note: If this number is left alone, a simulation with the same parameters and shapes will produce the same results every time, even if random numbers are used in the simulation.

Generators

Generators create cases that flow through the Simulation over time. The generators tab is a global tab for all generators in this diagram. From this tab, users may turn on and off any generator in the diagram, as well as edit any individual generator properties by clicking on the generator name.

More details on generator properties may be found on the Simulation Shape Properties page.

Resources

The resource tab allows users to manage the resources that are available to the simulation. At the most granular level, resources represent groups of people or bots, referred to as types. Types must be assigned to an organization. Currently, users may only assign types to accomplish activities in a simulation.

Organizations contain types. Organizations can be automatically created from swimlanes. See Swimlane Based Resources for an explanation of this.

Type Properties

Count

Defines the number of people or bots represented in this type.

Hourly Rate

The cost per hour of the type, when scheduled.

Schedule

Defines when this type is available. Available schedules for the resource are defined in the Schedules tab.

More properties

Per Use Cost

A cost that occurs when the resource is acquired. In most cases that will be just once per time it is used in an activity, but if a resource is preempted, or not released at the end of the activity, that will not be the case.

Overtime Hours

The amount of time per day that a resource can work when not in schedule. Resets the first time each day that the resource goes in schedule, so if a shift goes past midnight that does not reset the amount of overtime worked.

Overtime Rate

The cost per hour of the resource when it works overtime. If this property is not present, the resource costs its normal Hourly Rate when working overtime. This property only appears as an option once Overtime Hours is present.

Variables

A Variable is used to communicate information and manage the flow of cases through a simulation. A variable’s value can be assigned or changed at 5 points as a case is processed at an activity. See Assignments in Simulation Shape properties.

Variables may be defined at 5 different levels, 4 of which are part of a hierarchy. Model → Process → Activity → Case. Model variables are scoped to represent a simulation wide variable, whereas case variables are scoped specific to an individual case. Variables can have a different value for each instance of their scope. For example, case variables have a different value for each case; there is only one model for a given simulation, so model variables are the same for each case within the simulation.

Variables must have an initial value assignment, though the value may be changed throughout the course of the simulation.

Variables serve a variety of purposes, here are some common example cases:

Setting a global value to be used in multiple places in the simulation. Change the variable in one place instead of x number of places.
Determine which direction a case travels through a gateway depending on the value of a variable.

Note: Resource variables are not yet accessible.

Schedules

Schedules define periods of activity and inactivity, such as when a resource can do work or when a generator is generating cases.

Each Schedule is composed of a set of days and the hours during those days the schedule is active.

To define days, click on the navigation icon to the right of the Days box. That navigates to the Days menu, and clicking on one of the definitions allows editing which days are selected.

To define hours, click on the navigation icon to the right of the Hours box. That navigates to the Hours menu, and clicking on one of the definitions allows editing which hours are selected. Using the bar display, drag to extend/contract the bars and right click to create new bars/delete bars. Using the time span display, click “Edit” and add, remove, and adjust the time spans.

The last option on the schedule is the Composite option, which defines a schedule as a combination of other schedules. If the schedules overlap for a certain time span, the one on the bottom takes priority.

Timers

Timers trigger at certain defined points in time. This is currently used for Timer generators. The generator will generate cases every time the timer triggers.

The days when the timer triggers are defined the same way as described in the previous section, “Schedules”. The timer triggers at a certain time on those days, which can be changed in the “Time” field above.

It is also possible to define a timer as a combination of other timers using the Composite option.