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Tan et al. Complex Eng Syst 2023;3:6  I http://dx.doi.org/10.20517/ces.2023.10    Page 5 of 23


               where Ω    > 0 are the weighting matrix;       ∈ [0, 1] are the weighting parameters of the corresponding packet
               and satisfy  ∑           = 1.       (  ) are the memory event-triggered threshold and meet the following conditions
                            =1
                                                            
                                               1        0  ∑     (  )  T  (  )
                                      ¤
                                            (  ) = (  2  −  )        (Δ       (  )) Ω    Δ       (  ),  (5)
                                                (  )        (  )
                                                           =1
               where       (  ) ∈ (0, 1] and    0 > 0 is used to regulate the release rate of sampling data. The framework of the
               decentralized control for interconnected semi-Markovian jump systems with a dynamic METM is shown in
               Figure 1.


               Remark 1. From (5), we can obtain that the dynamic threshold       (  ) is related to the error variable     (  ) (  ).
                                                                                                         
               Whentheerrorvariabletendstozero,forinstance,thesystemtendstobestableattheequilibrium,thedynamic
               threshold converges to a constant. When       (  ) > 0,       (  ) is monotonically increasing, which means that the
                                                   ¤
               release rate of data at the sampling time will reduce. On the contrary, when       (  ) < 0,       (  ) is monotonically
                                                                               ¤
               decreasing, the release rate of data at the sampling time will increase. In particular, when       (  ) ≡ 0, the event-
                                                                                          ¤
               triggered condition becomes the traditional memory event-triggered condition [22] .

               Remark 2. By using the historical trigger signals, a memory-base event-triggered condition is proposed in (4),
               where the past events are assigned appropriate weighting values. This METM can not only save network re-
               sourcesbutalso canimprove thefault toleranceof the event-triggering mechanismcompared tothe traditional
               design.


               We divide the sampling time interval [      ℎ +       ,      +1 ℎ +      +1 ) into       + 1 parts as follows:

                                                                                                        (6)
                                             [      ℎ +       ,      +1 ℎ +      +1 ) = ∪        ,
                                                                      =0
               where    = 0, 1, 2, · · · ,      ,       = min{  |      ℎ+(  +1)ℎ+      ≥      +1 ℎ+     +1 } and       = [      ℎ+  ℎ+      ,      +1 ℎ+  ℎ+ℎ+     +1 ),
                     denotes the network induced delay. Define delay function       (  ) =    − (      ℎ +   ℎ), and we can get

                                            0 ≤       ≤       (  ) ≤       + ℎ ≤       ,    ∈       .   (7)

               Definetheerrorvariable     (  )  (  ) =       (     −  +1 ℎ)−      (      ℎ+  ℎ),andcombinethedelayfunction       (  ) =   −(      ℎ+  ℎ),
                                         
               then we can obtain
                                        (     −  +1 ℎ) =     (  ) (  ) +       (      ℎ +   ℎ) =     (  )  (  ) +       (   −       (  )).  (8)
                                                                      
               The control input       (  ) in system (1) can be designed as

                                                          
                                   ∑                   ∑      
                                   (  ) =     (      )      (     −  +1 ℎ) =     (      )[    (  )  (  ) +       (   −       (  ))],    ∈       .  (9)
                                                                      
                                     =1                  =1
               Based on the above analysis, system (1) can be rewritten as
                                                                                   
                                            ∑                    ∑              ∑
                                                                          (  )
                         ¤       (  ) = A            (  ) + B                (   −       (  )) + B              (  ) +  G              (  ),  (10)
                                                    
                                                                               
                                              =1                   =1            =1,  ≠  
                        
               where    is the controller gain matrix. Next, a definition and some lemmas will be innovated to deduce the
                          
               subsequent results of this paper.
               Definition 1( [16] ): Suppose   (  (  ),       ,    ≥ 0) is a functional candidate, then the infinitesimal operator =  (  )
               is represented as
                                                     {  (  (   +   ),      +   )|  (  ),       } −   (  (  ),       )
                                   =  (  (  ),       ) = lim                         .                 (11)
                                                  →0                  
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