1) CH 2- transportation problems Flashcards
what is a transportation problem
specialized LP model!
Characteristics and Assumptions-
Supply
only a specific amount of supply available from a few suppliers
C&A:
demand/ capacity
g/s demaded at many location
C&A
Quantities
the supply available and the demand requirmenets are cosntant (not increasing/decreasing)
C&A
shipping cost
the shipping cost from a to b is independant of the quantity shipepd (shipping more is not more cost///// we base shipping cost on the distance insteeda)
C&A
no transhipment
shipment only allowed from supplier to demander, no where iin between
C&A
integer values
all supply and demand quantities given in whole numbers!!!
C&A
problem formulation
decision variable determine how mnay units shipped from each supplier to each demander to maximize profit or minmze costs
How to determine opportunities in transportation problems
USE SHADOW PRICE!!!
1) See where it would cause greatest increase to sell one more unit of good (greatest shadow price)
binding constraints have a ___ shadowprice
NOT ZERO
non binding constraitns have a __ shadownprice
0
Assignment Problems
determine he most efficient one to one job allocation
Goal of assignment problems
minimize total cost or total time of performing the tasks// maximize preferences or ability
Characteristic of assignment problem:
each job assignment to ONLY ONE PERSON
How to do assignment question
1) just like regular, but set the constraints equal to the external rows/ columns
2) IF YOU DONT KNOW SUPPLY AND DEMAND- KNOW THAT IT NEEDS TO SUM TO THE GIVEN NUMBER (MIGHT ALL BE 1S)