My name is Mohamad Khaled and for my university research project I am using AIMMS to model a 3-echelon Pharmaceutical Supply Chain model. The current model I’m trying to define and solve is a simple one compared to some of the models I have seen here. I have two issues with my current model:
The first issue is that the pharmaceutical products (AKA medication) has an uncertain demand which I am not able to properly define in the project despite indicating the index domain, using the uncertain option in the property setting and defining the box function with an upper and a lower value in the region area. (I attached a screenshot of the demand parameter with the descriptions and region and another screenshot of the current “nominal” data of the demand)
The second issue is the wastage/expiration of the medication. I have defined a shelf-life variable and respective constraint, however, I couldn’t get the shelf-life variable to be used in the wastage constraint as the following warning message kept appearing: “Warning: Comparing elements of different sets is ambiguous. AIMMS will compare the elements based on the super set of the two sets. If this is not your intention, you can re-write the expression using the Ord function specifying the set explicitly. (see also the option warning_comparing_elements_different_sets).” What I am aiming to achieve is to incorporate and define the attached if-then formulas, which do work as they have been tested in a previous research study.
Note that for the wastage issue, I assigned a set called Medication_period, which refers to the time the medication was produced, to be a subset of the original time_period set.
I know that several users ask for your help, and that much more complex projects has been optimized by AIMMS, however I couldn’t find anything similar that would work for my model, which is why I’m asking for your help in this matter.
(Note: my supervisor suggested that a certain Add-on might be needed to be installed.)
Hope to hear from you soon,
Best answer by Marcel HuntingView original