Presentation is loading. Please wait.

Presentation is loading. Please wait.

Transportation problem Factories Customers Requirement for goods Production capacity... Minimum cost of transportation satisfying the demand of customers.

Similar presentations


Presentation on theme: "Transportation problem Factories Customers Requirement for goods Production capacity... Minimum cost of transportation satisfying the demand of customers."— Presentation transcript:

1 Transportation problem Factories Customers Requirement for goods Production capacity... Minimum cost of transportation satisfying the demand of customers. aiai aiai bjbj bjbj i-th factory delivers to j-th customer at cost c ij a1a1 a2a2 anan bmbm b1b1 b2b2

2 Transportation tableau 7 x 11 3 x 12 4 x 13 u18u18 4 x 21 2 x 22 2 x 23 u26u26 2 x 31 1 x 32 5 x 33 u33u33 v14v14 v22v22 v33v33 cost c ij of delivering from ith factory to jth customer supply a i of ith factory demand b j of jth customer shadow customer’s “price” shadow factory “price” shadow prices are relative to some baseline amount transported

3 Transportation problem a1a1 b1b1 a2a2 b2b2 b3b3 a3a3 a4a4 b4b4 7 x 11 3 x 12 4 x 13 u18u18 4 x 21 2 x 22 2 x 23 u26u26 2 x 31 1 x 32 5 x 33 u33u33 v14v14 v22v22 v33v33 7 x 11 3 x 12 4 x 13 0 x 14 u18u18 4 x 21 2 x 22 2 x 23 0 x 24 u26u26 2 x 31 1 x 32 5 x 33 0 x 34 u33u33 v14v14 v22v22 v33v33 v48v48 7 x 11 3 x 12 4 x 13 0 x 14 u18u18 4 x 21 2 x 22 2 x 23 0 x 24 u26u26 2 x 31 1 x 32 5 x 33 0 x 34 u33u33 9 x 41 8 x 42 11 x 43 0 x 44 u40u40 v14v14 v22v22 v33v33 v48v48

4 7 x 11 3 x 12 4 x 13 0 x 14 u18u18 4 x 21 2 x 22 2 x 23 0 x 24 u26u26 2 x 31 1 x 32 5 x 33 0 x 34 u33u33 v14v14 v22v22 v33v33 v48v48 Transportation Simplex Applying the Simplex method to the problem Basic solution – min-cost method Pivoting – shadow prices set u 1 = 0, then u i + v j =c ij – reduced cost pivot if u i + v j > c ij Finding a loop 0 2 0 6 take the smaller of the two 2 6 0 1 0 3 12 0 33 0 0 must mark exactly m + n – 1 = 6 cells cost = 3×7 + 3×4 + 2×0 + 1×2 + 2×1 + 6×0 = 37 z = 37

5 7 x 11 3 x 12 4 x 13 0 x 14 u18u18 4 x 21 2 x 22 2 x 23 0 x 24 u26u26 2 x 31 1 x 32 5 x 33 0 x 34 u33u33 v14v14 v22v22 v33v33 v48v48 Transportation Simplex Applying the Simplex method to the problem Basic solution – min-cost method Pivoting – shadow prices set u 1 = 0, then u i + v j =c ij – reduced cost pivot if u i + v j > c ij Finding a loop 6 2 12 33 z = 37 0 4 u i =0 and v j must sum up to c ij = 4v j = 4 7 0 -5 6 0

6 7 x 11 3 x 12 4 x 13 0 x 14 u18u18 4 x 21 2 x 22 2 x 23 0 x 24 u26u26 2 x 31 1 x 32 5 x 33 0 x 34 u33u33 v14v14 v22v22 v33v33 v48v48 Transportation Simplex Applying the Simplex method to the problem Basic solution – min-cost method Pivoting – shadow prices set u 1 = 0, then u i + v j =c ij – reduced cost pivot if u i + v j > c ij Finding a loop 6 2 12 33 z = 37 0 47 0 -5 6 0 calculate u i + v j -5 76 4 6 > > > > ≤ ≤

7 7 x 11 3 x 12 4 x 13 0 x 14 u18u18 4 x 21 2 x 22 2 x 23 0 x 24 u26u26 2 x 31 1 x 32 5 x 33 0 x 34 u33u33 v14v14 v22v22 v33v33 v48v48 Transportation Simplex Applying the Simplex method to the problem Basic solution – min-cost method Pivoting – shadow prices set u 1 = 0, then u i + v j =c ij – reduced cost pivot if u i + v j > c ij Finding a loop New basis 6 2 2+Δ2+Δ 11+Δ1+Δ 22-Δ2-Δ 33-Δ3-Δ 3 z = 37 0 47 0 -5 6 0 -5 76 4 6 > > > > ≤ ≤ +Δ+Δ 6-Δ6-Δ Largest feasible Δ = 2 2 4 4 1 3 z = 29


Download ppt "Transportation problem Factories Customers Requirement for goods Production capacity... Minimum cost of transportation satisfying the demand of customers."

Similar presentations


Ads by Google