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Resources and Shifts
Comparison of the three resource methods
Technique
Requirements Specification
Advantages
Resource Item Block
There is no dedicated user interface for specifying resource item require- ments. Typically, Queue Equation or Queue Matching blocks are used to hold items until the required resource items are available. Then, released items are batched with resource items.
1. Because resources are items, they can have properties that allow them to be distinguished indi- vidually.
2. Modelers have full control over the logic governing how resources are utilized.
Resource Pool Method
Requirements are speci- fied using a data table in the Queue. The table specifies the required quantities from one or more pools. The required pools are selected using the settings in the dialog. The required counts can be specified using attri- bute values or connectors.
1. Does not require con- nections to blocks.
2. Does not need complex routing logic to control the allocation and release of resources.
3. Resources automati- cally know which items are waiting for them.
4. Provides the capability to globally prioritize the allocation of resources to the highest ranked items.
Advanced Resource Management
Requirements are speci- fied using logical expres- sions created in the dialog of the Resource Manager block. These expressions consist of components that specify required quantities and filtering conditions that limit the set of resources to those wanted.
1. Does not require con- nections to blocks nor complex routing logic.
2. Resources automati- cally know which items are waiting for them.
3. The allocation of resources to the highest ranked items is globally prioritized; multi-tiered ranking is supported.
4. Resources have proper- ties that allow them to be distinguished individu- ally.
5. Allows for very com- plex resource require- ments and provides a flexible mechanism for creating resource release rules.
6. All information about resources is globally available to the model; details can be logged in the database.
Discrete Event


































































































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