Allocate a specific share of outflows from a stock

[geraldmashange]

Hi everyone. I need to include a second outflow to my "Harvested Corn" stock called "Corn Purchasing by Feedlot". How much is purchased by the cooperative and the feedlot is a function of their respective market share. Purchasing by the feedlot will only begin at time = 8. How can I direct the flow of corn to feedlots without entangling it with the flow to the cooperative? The cooperative has a storage capacity of 14 million bushels. So I also need to consider what happens to the corn in excess of the cooperative storage capacity.

I've set the "Expected Planted Acres" to a value so that there's no excess in the system.

[Administrator]

You can add a 2nd outflow in the same way you added the first outflow.

I'd pause first and have a think about the model you already have. For example, why are you delaying "harvest rate" to give "desired harvest rate"? The harvest rate should be dependent on the machinery, staff and corn ready for harvest, I cannot think of a reason to delay this in any way. I'd also expect the harvest rate to include a unit for area.

You have something similar for "Desired Purchase Rate". Logically, when an order is made, you allocate the amount to be delivered, and deliver it. Once an order is made, place the amount ordered into a new stock (corn on order), and deliver that after the delivery delay.

Hope this helps.

[geraldmashange]

You can add a 2nd outflow in the same way you added the first outflow.

I'd pause first and have a think about the model you already have. For example, why are you delaying "harvest rate" to give "desired harvest rate"? The harvest rate should be dependent on the machinery, staff and corn ready for harvest, I cannot think of a reason to delay this in any way. I'd also expect the harvest rate to include a unit for area.

You have something similar for "Desired Purchase Rate". Logically, when an order is made, you allocate the amount to be delivered, and deliver it. Once an order is made, place the amount ordered into a new stock (corn on order), and deliver that after the delivery delay.

Hope this helps.

Thank you for your feedback. I’m trying to represent the production of corn in multiple counties by hundreds of farmers. You’re right that the harvest rate will depend on the machinery and staff, however, historically, this rate is fairly constant. If the harvest size is small, the harvest ends faster. Moreover, I’m more interested in the operations of the cooperative.

Harvest begins in time = 8 and upon harvest, about 90% of the harvest gets sold immediately. On average, harvest lasts no more than 2 months so I used the average, historical total harvest divided by 2 to get the harvest rate. I’m delaying harvest rate because the corn has to grow first and it only matures in time = 8. And I’m assuming that 100% of the corn gets sold in this model.

I’m still not clear on the second outflow. The new outflow I need from “Harvested Corn” to the new stock “Feedlots” should be a function of market share. If the cooperative has a 40% market share, then no more than 40% of the “Harvested Corn” should go to the cooperative. When harvest is done, harvest is done. I don’t want any stock left in “Harvested Corn” when harvest is completed. Therefore, the second outflow should remove 60% from the “Harvested Corn”. I’m finding this difficult to incorporate into the model.

[tomfid]

A typical approach would be to (a) calculate the total outflow of sales, as a function of delayed harvest, then (b) split that 60/40 to make up the two individual flows.