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Page 140                         Ortiz et al. Intell Robot 2021;1(2):131-50  I http://dx.doi.org/10.20517/ir.2021.09


                                            r 1  , 1  1 1                r 1 n 1 ,  n
                                                 f  1     f  2    f  3         f  n  =  f  *
                                         r    Q 1 1   Q  1 2  Q  1 3       Q 1 n
                                          m  , 1  1 1                 r m n 1 ,  n
                                        r      r 2  , 1  1 1       r         r
                                        ( m  -  1 ) 1              (  m 1 -  ) n 1 ,  n  2  n 1 ,  n
                                        , 1 1   r 2  , 1  2 1      r          r
                                       r 3  , 1  1 1                3 n 1 ,  n  2  n 2 ,  n
                                              Q  2 1  Q  2 2  Q  2 3       Q 2  n
                                       r m  , 1  2 1  r 3  , 1  2 1  r m n 2 ,  n  r
                                      r        r 3  , 1  3 1      r (  m 1 -  ) n 2 ,  n  3  n 2 ,  n
                                       ( m  -  1 ) 1                          r 3  n 3 ,  n
                                       , 2 1
                                              Q       Q       Q            Q 3
                                               3 1     3 2     3 3           n
                                               r ( m  -  1 ) 1               r (  m 1 ) n
                                                                               -
                                                ,  3 1             r m n 3 ,  n  3 ,  n
                                       r m  , 1  3 1  r ( m  -  1 ) 1        r (  m 1 -  ) n
                                                ( , m  -  1 ) 1               ( ,  m 1 -  )  n
                                             Q  ( m  -  1 ) 1  Q  ( m  -  2 ) 1  Q  ( m  -  3 ) 1  Q (  m -  n ) 1
                                               r m  ( , 1 m  -  1 ) 1        r m n ( ,  m 1 -  ) n
                                                 r m  , 1 m  1                r m n ,  m n
                                              Q       Q       Q            Q
                                               m  1    m  2    m  3         m n
                                      Figure 2. Roadmap genetic algorithm model as a finite Markov chain.
                                                          
                                                       Í            
               Euclidean distance. The total fitness is        =         (       ). Therefore, the probability of selection       of a
                                                         =1
               chromosome       for    = 1, 2, . . . ,    is
                                                                  (          )
                                                            =                                         (37)
                                                                   
               An optimal solution    in    is mutated by
                                    
                                                                           
                                                               ©           (   )  ª
                                                               ­
                                                = lim (1 −       ) = lim ­1 −      ® ® = 1            (38)
                                                                      
                                                →∞           →∞ ­  Í          ®
                                                                            (   )
                                                                            
                                                               «     =1     ¬
               In the mutation operation, an optimal solution with        = 1 is a global solution if    → ∞. To prove the
               convergence, we use a Markov chain, as shown in Figure 2. Each chromosome can move from         to the state
                    (   +1). The moving probability is        ,     > 0,    = 1, 2, . . . ,   ,   ,    = 1, 2, . . . ,   .
               The operators, selection, crossing, and mutation create   (  ) with    . It preserves the best chromosomes of
                                                                          
                 (   − 1).   (   + 1) in the population   (  ) can be regarded as the Markov transition:
                                                                              
                                                                 
                                              {     +1 =      +1 |      =    } =   (     +1  ,    )   (39)
               Theorem 2 If GA for the roadmap is an elitist process, then the probability of    in    is exponential.
                                                                               ∗
               Proof 2 The iteration    1 is changed with the chromosomes when genetic process is elitist,
                                                                   
                                                                Õ            − 1
                                                   ∗
                                             (   1 =    ∀0 <    ≤   ) =       1,11 =                  (40)
                                                                              
                                                                   =2
                                                                                       
               where    is the size of the population. If for all   ,    ∈   , there is 0 <    ≤    such that    (  ,   ) ≥    > 0, then
                                                         
                                                 = min {   (  ,   )∀0 <    ≤   } ≤ 1                  (41)
               This implies that, given certain state       , the probability of transition in time    between    and    +    is at least   ,

                                                       ∗
                                                (      ≠    ∀   <    ≤    +   ) ≥ 1 −                 (42)

               Without loss of generality, the transition in the iteration    + 1 is

                                                       ∗
                                       (     +1 ) =   (      ≠    ∀0 <    ≤ (   + 1)  )
                                             ∗                     ∗
                                       (      ≠    ∀0 <    ≤       )  (      ≠    ∀     <    ≤ (   + 1)  )
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