EditingHoldModules < OpsRes

---+ Editing Hold Modules

_Hold_ modules belong to the _Advanced Process_ template (if you cannot find this template you may need to [[AttachArenaTemplate][attach it]]). After you have added a _Hold_ module by dragging it onto the flowchart view, you can edit it by double clicking. You can change the _Name_ of course, but the main functionality is determined by the _Type_. There are 3 types of _Hold_ module and we will discuss each one of them separately.

---++ Wait for Signal

This hold stores entities in a queue until a unique signal is recieved during the simulation. Each time the signal is received an entity leaves the _Hold_ module queue.

Consider the example of simulating cars queing at a parking building exit while waiting for their prepaid parking tickets to be approved. The cars ( _entities_) must wait for the signal 10 to be sent in the simulation. When this signal is sent, one car will proceed through the exit.
---++ Scan for Condition

This hold stores entities in a queue until a condition is satisfied. However, the _Hold_ module ONLY checks this condition WHEN A CALENDAR EVENT OCCURS. If the condition is true then the first entity in the queue may leave the _Hold_ module. This generates a new event and the condition is checked again. Each time the condition is true an entity leaves the _Hold_ module queue.

Below is an example of a _Scan for Condition Hold_ module from the Case Study: Courier Service Model.

<img width="320" alt="Hold_Scan_for_Condition.PNG" src="%ATTACHURL%/Hold_Scan_for_Condition.PNG" height="263" />
---++ Infinite Hold

This hold stores entities in a queue infinitely while the simulation is running.

NB: An infinite hold is usually combined with a _Search_ module and a _Remove_ module (See Arena help for more details).

-- Main.MichaelOSullivan - 25 Aug 2009

   * Hold_for_signal.PNG: <br />
     <img src="%ATTACHURLPATH%/Hold_for_signal.PNG" alt="Hold_for_signal.PNG" width='320' height='263' />
This topic: OpsRes > WebHome > ArenaGuide > EditingHoldModules
Topic revision: r6 - 2010-02-04 - KatTrevor