Mixing
How is delta value determined in this transshipment problem?
$begingroup$
I am trying to understand how this transshipment problem is optimized from step to step. I have the answer on the exercice, but cannot really get it. The main point is clear: We want to transport (in this example) 7(node1)+3(node5)=10 pieces to 4(node2)+4(node6)+2(node8) at minimal cost. The costs are written in orange on every edge. But how the optimization steps are done? What is checked and on what the change of the path (edges) is based?
Here is the exercice:
How did we move from step 1 (left) to step 2 (right) for example?
Okay, how the yi's (written in red on every node) are calculated, is understandable. But what are these numbers for ex in the first step (graph):
- "-18" from node1 to node2 (written in green)?
- "-6" from node5 to node6 (written in green)?
- "-1" from node1 to node4 (written in green)?
- "-1" from node5 to node8?
- What is delta = 1?
- And why on one edge (from node1 to node2) +delta (written in pink)and in others -delta (written in pink)?
What have been calculated to get these numbers? And why the professor calculated just these edges and not the others?
I am getting really frustrated, as this chapter is very important for the exam, which is the last exam of my Bachelors, and I am really not getting what is getting improved from step to step (from graph to graph), and what is the goal? What should we have in the last step, as optimal solution? :-/
In the second graph, why are few edges checked (as if everything is okay with them, like edge from node6 to node3, or edge from node3 to node5, or edge from node8 to node6) and others not, and numbers in green are written on them (like edge from node5 to node8=19 or edge from node5 to node6=-24)? And why is delta = 3?
I would really appreciate any help here! Thank you so much for every effort to explain me this.
EDIT:
Ok, got all the answers. Just one question:
- How is the value of delta determined?
Thank you!
optimization operations-research network-flow network
asked Jan 31 at 23:55
ZelelBZelelB
1297
$endgroup$
add a comment |
$begingroup$
I am trying to understand how this transshipment problem is optimized from step to step. I have the answer on the exercice, but cannot really get it. The main point is clear: We want to transport (in this example) 7(node1)+3(node5)=10 pieces to 4(node2)+4(node6)+2(node8) at minimal cost. The costs are written in orange on every edge. But how the optimization steps are done? What is checked and on what the change of the path (edges) is based?
Here is the exercice:
How did we move from step 1 (left) to step 2 (right) for example?
Okay, how the yi's (written in red on every node) are calculated, is understandable. But what are these numbers for ex in the first step (graph):
- "-18" from node1 to node2 (written in green)?
- "-6" from node5 to node6 (written in green)?
- "-1" from node1 to node4 (written in green)?
- "-1" from node5 to node8?
- What is delta = 1?
- And why on one edge (from node1 to node2) +delta (written in pink)and in others -delta (written in pink)?
What have been calculated to get these numbers? And why the professor calculated just these edges and not the others?
I am getting really frustrated, as this chapter is very important for the exam, which is the last exam of my Bachelors, and I am really not getting what is getting improved from step to step (from graph to graph), and what is the goal? What should we have in the last step, as optimal solution? :-/
In the second graph, why are few edges checked (as if everything is okay with them, like edge from node6 to node3, or edge from node3 to node5, or edge from node8 to node6) and others not, and numbers in green are written on them (like edge from node5 to node8=19 or edge from node5 to node6=-24)? And why is delta = 3?
I would really appreciate any help here! Thank you so much for every effort to explain me this.
EDIT:
Ok, got all the answers. Just one question:
- How is the value of delta determined?
Thank you!
optimization operations-research network-flow network
asked Jan 31 at 23:55
ZelelBZelelB
1297
$endgroup$
add a comment |
$begingroup$
I am trying to understand how this transshipment problem is optimized from step to step. I have the answer on the exercice, but cannot really get it. The main point is clear: We want to transport (in this example) 7(node1)+3(node5)=10 pieces to 4(node2)+4(node6)+2(node8) at minimal cost. The costs are written in orange on every edge. But how the optimization steps are done? What is checked and on what the change of the path (edges) is based?
Here is the exercice:
How did we move from step 1 (left) to step 2 (right) for example?
Okay, how the yi's (written in red on every node) are calculated, is understandable. But what are these numbers for ex in the first step (graph):
- "-18" from node1 to node2 (written in green)?
- "-6" from node5 to node6 (written in green)?
- "-1" from node1 to node4 (written in green)?
- "-1" from node5 to node8?
- What is delta = 1?
- And why on one edge (from node1 to node2) +delta (written in pink)and in others -delta (written in pink)?
What have been calculated to get these numbers? And why the professor calculated just these edges and not the others?
I am getting really frustrated, as this chapter is very important for the exam, which is the last exam of my Bachelors, and I am really not getting what is getting improved from step to step (from graph to graph), and what is the goal? What should we have in the last step, as optimal solution? :-/
In the second graph, why are few edges checked (as if everything is okay with them, like edge from node6 to node3, or edge from node3 to node5, or edge from node8 to node6) and others not, and numbers in green are written on them (like edge from node5 to node8=19 or edge from node5 to node6=-24)? And why is delta = 3?
I would really appreciate any help here! Thank you so much for every effort to explain me this.
EDIT:
Ok, got all the answers. Just one question:
- How is the value of delta determined?
Thank you!
optimization operations-research network-flow network
asked Jan 31 at 23:55
ZelelBZelelB
1297
$endgroup$
I am trying to understand how this transshipment problem is optimized from step to step. I have the answer on the exercice, but cannot really get it. The main point is clear: We want to transport (in this example) 7(node1)+3(node5)=10 pieces to 4(node2)+4(node6)+2(node8) at minimal cost. The costs are written in orange on every edge. But how the optimization steps are done? What is checked and on what the change of the path (edges) is based?
Here is the exercice:
How did we move from step 1 (left) to step 2 (right) for example?
Okay, how the yi's (written in red on every node) are calculated, is understandable. But what are these numbers for ex in the first step (graph):
- "-18" from node1 to node2 (written in green)?
- "-6" from node5 to node6 (written in green)?
- "-1" from node1 to node4 (written in green)?
- "-1" from node5 to node8?
- What is delta = 1?
- And why on one edge (from node1 to node2) +delta (written in pink)and in others -delta (written in pink)?
What have been calculated to get these numbers? And why the professor calculated just these edges and not the others?
I am getting really frustrated, as this chapter is very important for the exam, which is the last exam of my Bachelors, and I am really not getting what is getting improved from step to step (from graph to graph), and what is the goal? What should we have in the last step, as optimal solution? :-/
In the second graph, why are few edges checked (as if everything is okay with them, like edge from node6 to node3, or edge from node3 to node5, or edge from node8 to node6) and others not, and numbers in green are written on them (like edge from node5 to node8=19 or edge from node5 to node6=-24)? And why is delta = 3?
I would really appreciate any help here! Thank you so much for every effort to explain me this.
EDIT:
Ok, got all the answers. Just one question:
- How is the value of delta determined?
Thank you!
optimization operations-research network-flow network
optimization operations-research network-flow network
asked Jan 31 at 23:55
ZelelBZelelB
1297
asked Jan 31 at 23:55
ZelelBZelelB
1297
edited Feb 1 at 1:19
ZelelB
asked Jan 31 at 23:55
ZelelBZelelB
1297
asked Jan 31 at 23:55
ZelelBZelelB
1297
asked Jan 31 at 23:55
ZelelBZelelB
1297
1297
add a comment |
add a comment |
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