Uitwerking practical 6 decision science

Decision Science 1, Computer Practical,
Practical work, Week 6 P6 Pair number: 14

Name: Lars van der Horst Studentnumber: 1 0 4 9 5 2 8
Name: Dennis van den Berg Studentnumber: 1 0 4 8 1 6 8

Exercise 14
Solve the integer LP-problem in exercise 14 with the Branch and Bound (B&B) method.
Draw the B&B-tree. Do not solve the generated subproblems graphically, but solve them with Xpress-
IVE. Use standard.mos as a basis, and branch by adding the constraints (such as “X1 >= 5”) to your
model explicitly.
You can insert a photo of your hand-drawn B&B tree here.




Exercise 11
11-a Nonpreemptive goal programming (Rural area problem)
Use goal programming to formulate the problem and solve it with Xpress-IVE. Give the solution of the
problem.
Deviational variables like d1+ and d1- should be named d1p and d1m.
Min: 1000*(d1m+d1p) + d2m + d2p + d3m + d3p
3000*X1+5000*X2+4000*X3 + d1m – d1p = 70000
150*X1 + 75*X2 + 100*X3 + d2m – d2p = 1750
10*X1 + 15*X2 + 12*X3 +d3m – d3p = 200
X1 + X2 + X3 <=15000

Objective function value = 28.33333333

Variables
X1 = 8.333333333
X2 = 6.666666667
X3 = 0
d1m = 11.66666667
d1p = 0