3 research outputs found
Stability analysis for continuous-time switched systems with stochastic switching signals
This paper is concerned with the stability problem of randomly switched systems. By using the probability analysis method, the almost surely globally asymptotical stability and almost surely exponential stability are investigated for switched systems with semi-Markovian switching, Markovian switching and renewal process switching signals, respectively. Two examples are presented to demonstrate the effectiveness of the proposed results, in which an example of consensus of multi-agent systems with nonlinear dynamics is taken into account
Finite-time synchronization of Markovian neural networks with proportional delays and discontinuous activations
In this paper, finite-time synchronization of neural networks (NNs) with discontinuous activation functions (DAFs), Markovian switching, and proportional delays is studied in the framework of Filippov solution. Since proportional delay is unbounded and different from infinite-time distributed delay and classical finite-time analytical techniques are not applicable anymore, new 1-norm analytical techniques are developed. Controllers with and without the sign function are designed to overcome the effects of the uncertainties induced by Filippov solutions and further synchronize the considered NNs in a finite time. By designing new Lyapunov functionals and using M-matrix method, sufficient conditions are derived to guarantee that the considered NNs realize synchronization in a settling time without introducing any free parameters. It is shown that, though the proportional delay can be unbounded, complete synchronization can still be realized, and the settling time can be explicitly estimated. Moreover, it is discovered that controllers with sign function can reduce the control gains, while controllers without the sign function can overcome chattering phenomenon. Finally, numerical simulations are given to show the effectiveness of theoretical results
Stability of the supply chain based on disruption classification
PoremeÄaji mogu uniÅ”titi stabilnost opskrbnog lanca Å”to rezultira poslovnim gubitkom, pa je odreÄivanje utjecaja raznih poremeÄaja na opskrbni lanac znaÄajno. MeÄutim, postojeÄe su se analize uglavnom usredotoÄile na stabilnost opskrbnog lanca u normalnim uvjetima, a istraživale su uÄinke razine zaliha na stanje sustava i izostavljale utjecaj poremeÄaja. S nedostatkom analize o karakteristikama poremeÄaja prilikom modeliranja prebacivog sustava, poremeÄaji su klasificirani i odreÄeno je vrijeme provedbe svake poremeÄene razine. Predložena su dvojna pravila prebacivanja s obzirom na dinamiku zaliha i zastoja u isporuci. IzraÄen je model prebacivog sustava opskrbnog lanca s viÅ”estrukim zastojima. Stabilnost sustava pod razliÄitim razinama poremeÄaja ispitana je pomoÄu simulacijske metode. Rezultati pokazuju da se opseg stabilnosti koeficijenata prilagodbe zaliha smanjuje s porastom koeficijenta vremena prijevoza i udaljenosti. Klasifikacija poremeÄaja ima razliÄite uÄinke na opskrbni lanac. Pod poremeÄajem na visokoj razini, razina zaliha proizvodnje znaÄajno se mijenja, a sustav opskrbnog lanca gubi svoju stabilnost i susreÄe se s poteÅ”koÄama u vraÄanju na stabilno stanje. MeÄutim, pod opÄim poremeÄajem, sustav opskrbnog lanca postupno se vraÄa u stabilnost. SadaÅ”nje istraživanje obogaÄuje pomaknutu metodu modeliranja opskrbnog lanca i pomaže Älanovima lanca da uÄinkovito sprjeÄavaju i reagiraju na poremeÄaje.Disruptions can destroy the stability of a supply chain resulting in losses in business, thus, determining the influence of various disruptions on a supply chain is significant. However, current studies have mainly concentrated on the stability of a supply chain under normal conditions, exploring the effects of inventory level on the system state and omitting the influences of disruptions. With the lack of analysis on the characteristics of disruption when modelling switched system, disruptions were classified and the lead time of each disruption level was determined. Dual switch rules were proposed considering the stock dynamics and lead time delays. A switched system model of the supply chain with multiple delays was then constructed. System stability under different level disruptions was investigated using simulation method. Results show that the stability scope of inventory adjustment coefficients decreases as transport lead time and distance coefficients increase. Disruption classification has different effects on the supply chain. Under high level disruption, the inventory level of manufacture significantly changes, and the supply chain system loses its stability and encounters difficulty in recovering its stable state. However, under general disruption, the supply chain system recovers to stability gradually. The present exploration enriches the switched modelling method of the supply chain and helps its chain members prevent and respond to disruptions effectively