Page 133 - IJOCTA-15-1
P. 133

Duality for robust multi-dimensional vector variational control problem under invexity
                                                                     h                               i
                                                                        T               T
                                                                 −D κ λ θ ζ κ  (Π, ζ κ , b)+τ β ζ κ (Π, ζ κ , µ) =0,
               Z
                                         ¯ T
                                                     ¯
                                               ¯
             +   D κ η(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω)λ θ σ κ (Λ, ¯σ κ , b)dν+                          (10)
                                                                T
                                                                                            T
                                                                             T
                Ω                                             χ Ψ ϱ (Π, ¯ a)+λ θ ϱ (Π, ζ κ , b)+τ β ϱ (Π, ζ κ , µ)=0,
               Z
                                      ¯ T
                                            ¯
                                                  ¯
                  ξ(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω)λ θ ω (Λ, ¯σ κ , b)dν  (8)                           (11)
                                                                            ζ(t 0 )=δ 0 , ζ(t 1 )=δ 1 ,  (12)
                Ω
                                                                                  p
                                Z
                                    T
            Further, invexity of   ¯ τ β(., ., ¯µ)dν and robust            χ≧0,  X  χ i =1, λ≧0,         (13)
                                  Ω
            feasibility of (ˆσ, ˆω)∈T gives                                      i=1
                                                              for ¯a ∈A, b∈B, µ∈M .
                  Z
                                          T
                                               ¯
              0≧    η(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω)¯τ β σ (Λ, ¯σ κ , ¯µ)dν  Denote T w ={(ζ,ϱ,χ,λ,τ,¯ a,b,µ) satisfying (10)−
                   Ω                                          (13)} as the set of feasible solutions of (WD).
              Z
                                               ¯
                                         T
            +    D κ η(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω)¯τ β σ κ (Λ, ¯σ κ , ¯µ)dν+  Theorem 3.  [Weak Duality Theorem]  Let
               Ω
                                                              (σ, ω)  and   (ζ, ϱ, χ, λ, τ, ¯ a, b, µ)  be  the  ro-
              Z
                                       T
                                           ¯
                 ξ(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω)¯τ β ω (Λ, ¯σ κ , ¯µ)dν. (9)  bust  feasible  solutions  of  (RUVP)  and
                                                                                                Z
                Ω
                                                              (WD), respectively.   Further, if    Ψ(., ¯ a)dν,
            Adding inequalities (7), (8) and (9), we have
                                                                                                  Ω
                                                              Z                     Z
                    Z
                                                                T                     T
                                                   ¯
                                             T
                0>    η(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω) ¯χ Ψ σ Λ, ¯ a  λ θ(., ., b)dν and  τ β(., ., µ)dν are in-
                     Ω                                         Ω                     Ω                q
                                                              vex  w.r.t.      η(t, σ, ζ, σ κ , ζ κ , ω, ϱ)∈R  and

                                          ¯
                                ¯
                          ¯
                                     T
                    ¯ T
                  +λ θ σ (Λ, ¯σ κ , b)+ ¯τ β σ (Λ, ¯σ κ , ¯µ) dν  ξ(t, σ, ζ, σ κ , ζ κ , ω, ϱ)∈R at (ζ, ϱ), then
                                                                                     r
               Z

                                                      ¯
                                                 ¯
                                          ¯ T
             +   D κ η(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω) λ θ σ κ (Λ, ¯σ κ , b)dν  Z  Z
                                                                                              T
                Ω                                                  Ψ(Λ, ¯ a)dν <   Ψ(Π, ¯ a)+λ θ(Π, ζ κ , b)+

                             T    ¯                              Ω              Ω
                          +¯τ β σ κ (Λ, ¯σ κ , ¯µ) dν

                                                                              T
                  Z                                                          τ β(Π, ζ κ , µ) dν

                                                 ¯
                                            T
                +    ξ(t, ¯σ, ˆσ, ¯σ κ , ˆσ κ , ¯ω, ˆω) ¯χ Ψ ω Λ, ¯ a +
                   Ω                                          cannot hold.

                                         ¯
                               ¯
                         ¯
                   ¯ T
                                    T
                   λ θ ω (Λ, ¯σ κ , b)+ ¯τ β ω (Λ, ¯σ κ , ¯µ) dν  Proof.  Suppose, on the contrary
                                                                 Z              Z
            which is a contradiction to (6). Hence, (¯σ, ¯ω) is                                T
                                                                    Ψ(Λ, ¯ a)dν <   Ψ(Π, ¯ a)+λ θ(Π, ζ κ , b)
            a robust weak efficient solution for the problem      Ω              Ω
            (RUVP).                                                            T
                                                                            +τ β(Π, ζ κ , µ) dν.
                                                                                   p
            3. Wolfe type dual and duality                                        X
                                                              As (σ, ω)∈T , χ≧0,     χ i =1 and λ≧0,
                theorems
                                                                                  i=1
            Taking    maxΨ(Π, a)=Ψ(Π, ¯ a),    where   Π=      Z
                                                                                            T
                                                                              T
                      a∈A                                          Ψ(Λ, ¯ a)+λ θ(Λ, σ κ , b)+τ β(Λ, σ κ , µ) dν
            (t, ζ(t), ϱ(t)), the Wolfe-type dual for the problem  Ω
            (RUVP) is formulated as follows :                   Z
                                                                               T
                                                                                             T
                                                              <     Ψ(Π, ¯ a)+λ θ(Π, ζ κ , b) +τ β(Π, ζ κ , µ) dν,
                                                                 Ω
                              Z
                                                                                                        (14)
                                            T
              (WD)      max       Ψ(Π, ¯ a)+λ θ(Π, ζ κ , b)+            Z               Z
                                                                                            T
                      (ζ(.),ϱ(.))  Ω                             Since     Ψ(., ¯ a)dν,   λ θ(., ., b)dν  and
                                                                         Ω              Ω
                            T
                           τ β(Π, ζ κ , µ) dν =               Z   T
                                                                 τ β(., ., µ)dν are invex at (ζ, ϱ),   there-

              Z                                                Ω

                                            T
                              T
                  Ψ 1 (Π, ¯ a)+λ θ(Π, ζ κ , b)+τ β(Π, ζ κ , µ) dν,  fore  there  exist  η(t, σ, ζ, σ κ , ζ κ , ω, ϱ)  and
               Ω                                              ξ(t, σ, ζ, σ κ , ζ κ , ω, ϱ) such that
                       Z

                                       T
                    ... ,  Ψ p (Π, ¯ a)+λ θ(Π, ζ κ , b)+           Z   T             Z   T
                         Ω                                            χ Ψ(Λ, ¯ a)dν −  χ Ψ(Π, ¯ a) dν ≧
                                                  !
                                                                     Ω                Ω
                                                                  Z
                                  T
                                 τ β(Π, ζ κ , µ) dν                                        T
                                                                      η(t, σ, ζ, σ κ , ζ κ , ω, ϱ)χ Ψ ζ (Π, ¯ a)dν
                                                                     Ω
                               subject to                         Z
                                                                                          T
                T
                                            T
                             T
               χ Ψ ζ (Π, ¯ a)+λ θ ζ (Π, ζ κ , b)+τ β ζ (Π, ζ κ , µ)  +  ξ(t, σ, ζ, σ κ , ζ κ , ω, ϱ)χ Ψ ϱ (Π, ¯ a)dν,  (15)
                                                                    Ω
                                                           127
   128   129   130   131   132   133   134   135   136   137   138