Hi,
I want to model the required amount of consumable relief items (such as water, medicine,etc..) for an evacuation scenario. I developed a simple model based on the following formula:
p(t)=1/(1+EXP(-α*(Time-H))^2)
where Pt is the percentage of the evacuees who have departed by
time t and α and H are model parameters to be calibrated. α gives
the slope of the cumulative traffic loading curve, and H is half loading
time: the time when half of the vehicles in the system are loaded
onto the highway network.
I want to calculate the amount of "required relief items" based on the stock of "population in the shelter.
1. Is my formulation correct in the attached model?
2. what could be the possible units for a multiplier to change "person" to "kit/person"? (this is for the variable "required relief commodities")
3. Can I use the variable "required relief commodities" as demand input to a stock management model, that fulfills this demand? what could be other possible ways to fulfill this demand?
how to convert the units from "person" to "kit/person"
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how to convert the units from "person" to "kit/person"
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Re: how to convert the units from "person" to "kit/person"
I cannot answer 1 and 3.
Are you thinking of the correct units here? I'd expect to see a population (measured in people) and maybe kits per person (kit/person), multiply these together to get kits required.2. what could be the possible units for a multiplier to change "person" to "kit/person"? (this is for the variable "required relief commodities")
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Units are important!
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Re: how to convert the units from "person" to "kit/person"
Yes, I want to have correct units in my model. attached is the revised version of the model. could you please check and confirm if the units are correct now.
how about the formulation for the rate "leaving the shelter", is the formulation correct?
Also the behavior of the model, do you think looks logical?
regards,
how about the formulation for the rate "leaving the shelter", is the formulation correct?
Code: Select all
(Population in shelter*Fraction of population leaving shelter)/average length of stay in shelter
regards,
- Attachments
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- Demad formulation 2 based on Logit function.mdl
- revised model
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Re: how to convert the units from "person" to "kit/person"
You can do this yourself, click the units check tool (or hit CTRL->U).anjomshoae wrote: ↑Sat Jun 16, 2018 5:11 am Yes, I want to have correct units in my model. attached is the revised version of the model. could you please check and confirm if the units are correct now.
I cannot tell you if the formulation is correct. In this case, I'd expect one of the following to be correct.anjomshoae wrote: ↑Sat Jun 16, 2018 5:11 amhow about the formulation for the rate "leaving the shelter", is the formulation correct?
leaving shelter = Population In Shelter / AVERAGE LENGTH OF STAY IN SHELTER
or
leaving shelter = Population In Shelter * FRACTION OF POPULATION LEAVING SHELTER
Advice to posters seeking help (it really helps us to help you)
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559
http://www.ventanasystems.co.uk/forum/v ... f=2&t=4391
Units are important!
http://www.bbc.co.uk/news/magazine-27509559