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Page 2 of 15                    Sun et al. Complex Eng Syst 2022;2:17  I http://dx.doi.org/10.20517/ces.2022.48



               1. INTRODUCTION
               Switched systems are important dynamic systems. The idea of switching has been widely applied in various
                                                                  [2]
                                                                                       [3]
                                              [1]
               fields, such as aircraft attitude control , ecological dynamics , and financial markets . With the increasing
               complexity of system architectures, dynamical analysis of switched systems has attracted significant academic
               interest. A switched system consists of a family of continuous-time dynamics, discrete-time dynamics, and
               switching rules between subsystems. According to the switching signal features, switched systems are divided
               intotwocategories, namely, deterministicswitchedsystemsandrandomlyswitchedsystems. Manyresearchers
                                                                                               [4]
               have focused on stabilization and stability analyses of various switched systems. For example, in , a series of
               results on stochastic differential equations (SDEs) with Markovian switching was obtained. In particular, the
                                                              [5]
               authors have provided some useful stability criteria. In , the authors studied the input-to-state stability of
               time-varying switched systems by employing the ADT method coupled with the MLF approach. The authors
                 [6]
               of investigated the stability of switched stochastic delay neural networks with all unstable subsystems based
                                                                  [7]
               on discretized Lyapunov-Krasovskii functions (DLKFs). In , a novel Lyapunov function was designed to
                                                                                        [8]
               ensure a non-weighted L 2 gain for switched systems with asynchronous switching. In , a hidden Markov
               model was proposed to study the finite region    ∞ asynchronous control problem for two-dimensional Markov
               jump systems. Other interesting researches on switched systems can be found in [9–11]  and references therein.

               The linear growth condition (LGC) is crucial for ensuring the existence of a global solution for a stochastic
               system. However, many stochastic systems do not satisfy LGC. Hence, the solution of a stochastic system
               may explode in a finite time. Recently, the stability of stochastic systems without LGC has drawn consider-
               able attention. For instance, the authors of [12]  investigated the stability and boundedness of nonlinear hybrid
               stochastic differential delay equations without LGC based on a Lyapunov function approach. By introducing a
               polynomial growth condition (PGC), [13]  discussed the stabilization problem of highly nonlinear hybrid SDEs.
               The input-to-state practically exponential stability in the sense of mean square was introduced in [14] . Suffi-
               cient conditions for stability have been obtained. Additionally, other meaningful results were reported in [15]
               and [16] .

               Time-delayisanimportantfactorthataffectsdynamical performancesofstochastic systems. Byconstructinga
               suitableLyapunovfunction, theauthorsof [12]  studiedthestabilityandboundednessofhighlynonlinearhybrid
               stochastic systems with a time delay. The authors of [17]  used the ADT method to study the stability problem of
               SSSs, where the switching signals are deterministic. Based on the stability criteria for stochastic time-delay sys-
               tems, the authors of [18]  introduced a suitable Lyapunov-Krasovskii (L-K) functional, and discussed the global
               probabilistic asymptotic stability of the closed-loop system. In [19] , the Razumikhin approach was presented to
               study the exponential stability of a class of impulsive stochastic delay differential systems. Using the piecewise
               dynamic gain method, the authors of [20]  studied the global uniform ultimate boundedness of switched linear
               time-delay systems. Motivated by the aforementioned literature, the stability of highly nonlinear SSSs with
               time-varying delays is studied in this paper. Figure 1 shows the framework of this paper.


               The challenges of this article lie in the following two parts: (1) The time delay studied here is merely a Borel
               measurable function of time   . That is to say, it may be non-differentiable with respect to time   , which means
               that the existing methods regarding constant delays or differentiable delays are no longer applicable; (2) Rather
               thanaMarkovianswitchingsignal,adeterministicswitchingsignalisinvolvedinthestudiedsystem,indicating
               thatMarkovianswitchedsystemsbasedM-matrixmethodisinvalid. Toaddresstheinfluencesofdeterministic
               switching signals, an ADT method coupled with the MLF approach is utilized in our stability analysis.


               The main advantages of this paper are as follows:
               (1) Without the LGC, the existence and uniqueness of a global solution is proven for highly nonlinear SSSs,
               where a deterministic switching signal rather than a Markovian switching signal is considered.
               (2) By integrating the ADT method and MLF approach, the   th moment exponential stability and almost
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