The EXCESS=DEMAND Option
If you specify the EXCESS=DEMAND option, then there are three possible scenarios to deal with:
- Case 1: No Node with Missing S Supply, THRUNET Not Specified (see Figure 5.37)
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Supply the excess demand to all demand nodes directly.
Figure 5.37: Nodes with Missing D Demand
- Case 2: Some Nodes with Missing S Supply, THRUNET Not Specified (see Figure 5.38)
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Supply the excess demand by the nodes that have a missing S supply value. If a node has a missing S supply value, then the amount it supplies is determined by optimization. For a supply node with a positive supdem value, that value is equal to the sum of flows on all actual arcs directed away from that node.
Figure 5.38: Nodes with Missing S Supply
- Case 3: THRUNET Specified (see Figure 5.39)
-
Supply the excess demand by all supply nodes. If a node has a positive supdem value, that value is the lower bound on the sum of flows on all actual arcs directed away from that node. If a node has a missing S supply value, then the amount it supplies is determined by optimization.
Figure 5.39: Nodes with Missing S Supply, THRUNET Specified
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