location and transportation model

Problems with modeling
fstone
User Posts: 2
Joined: 2 years ago

location and transportation model

Hi,
In my problem I have a node network, where nodes have different roles. Some nodes can only open like plant, some node can only open like supplier type A , some node can only open like supplier type B and some node can open like plant or supplier. I create a set with all node

set n nodes /n1*n10/

And i create a subset for each type of node

sets nj(n) node can be plant /n3,n5,n6,n9,n10/
ni(n) node can be supplier type A /n1,n2,n3,n4,n6,n7,n8/
nk(n) node can be supplier type B /n3,n4,n6,n8/

After the binary variable
Y(nj) if in node n is open a plat
X(ni) if in node n is open a supplier type A
X(nk) if in node n is open a supplier type B
A(ni,nk) if stablish link supplier and plant

Positive variable
f(ni,nj) flow between plant and supplier type A

Equation(n) is possible open one type of facilities per node
EQ2 Limit of number of plat
EQ3 Limit of number of upplier type A
EQ4 lLimit of number of upplier type B
EQ5(ni,nj,m) Logical flow restriction ;

Equation(n).. sum(nj(n),Y(nj)) + sum(ni(n),X(ni)) + sum(nk(n),Z(nk)) =e= 1 ;
EQ2.. sum(nj(n), Y(nj)) =e= NY ;
EQ3.. sum(ni(n), X(ni)) =e= NX ;
EQ4.. sum(nk(n), Z(nk)) =e= NKk ;
EQ5(ni,nj).. F(ni,nj,m) =l=bigM*A(ni,nj);

The problem is that it establishes link between nodes of subset ni and subset nj, does not consider the Equation(n) and the link is only posible between the open node supplier and the open node plant, not all.