SIMUL8 Feature List - Clock

High Speed Clock

Changing and updating the clock display can take a significant proportion of run time. While the most aesthetically pleasing view of the clock is achieved by keeping the clock exactly in line with events on the screen, this is slower than using the "automatic" clock refresh mode.

In Automatic mode the clock is updated only once every 1/10th of a second.

An accelerated version of the high speed clock is automatically used whenever the animation mode is off.

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The Run button is used to start a new simulation run or to stop a simulation which is already in progress.

More precise controls allow you to get your simulation to exactly the point you want. You can even run the simulation backwards! This is invaluable when you're debugging your simulation.

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The Step function allows you to walk through the simulation event by event. This is particular useful when you are debugging a simulation.

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Pressing Reset resets the simulation to time zero. This keeps the memory usage low and SIMUL8 files to a minimum.

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Shift patterns lets you say at what times of day parts of your simulation work. They also let you control how many Resources or Activities should be available throughout the day.

The behavior tab lets you control what should happen to work being done when a shift ends. Work can be suspended until the next shift, abandoned, or completed.

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Random Numbers

Random numbers enable a simulation model to include the variability which occurs in real life.

Each place where random numbers are used within a simulation uses a separate stream of random numbers. This enables a change to be made to one aspect of a model, without affecting the random occurrences which will happen at other areas.

By default, when the clock is set back to the start of the simulation time, all the random streams are reset to their starting seeds. This means that a second run of the same model will produce the same results.

The set of random numbers used can be changed. There are 30 000 sets of random number streams available in SIMUL8.

SIMUL8 uses a modified "Multiplicative Congruential" Pseudo random number generator (PRNG). Other types RNGs can be installed but this requires an additional fee. Please email .

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Antithetic Numbers

Antithetic numbers are available in SIMUL8. Selecting Antithetic numbers reverses all the random numbers.

Before random numbers are used in distributions, they are all in the range 0.00000 to 1.00000. Antithetic random numbers are exactly the same streams of numbers except they range from 1.00000 to 0.00000.

Changing to the antithetic of a set of random numbers is a quick way to see if the random numbers are having a large impact on the result of a model.

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Some elements are not identified when defining shift availability for your staff. What about holidays or special days? These can all be specified using the new calendar feature. A calendar of availability can be specified for each Activity, Resource, Start Point and even the simulation as a whole.

You can set up as many calendars as are required by the simulation model. If different Activities, or different Resources, run on different schedules, then individual calendars are required. If no calendar is assigned to a specific area, the main calendar will be assumed to define the operating schedule of the resource or Activity. In this way if only one calendar is required then the entire simulation system follows that operating schedule.

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Dynamic Calendars for Object Availability

Lets you set simulation objects to work to a calendar and control up and down time of your simulation objects and resources by date.

Now no need for time check logic.

Recurring events just like in MS Outlook.

Includes new Visual Logic commands allowing you to completely configure and control your calendars even at run time.


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