The features of the main models of spiking neurons are discussed in this review. We focus on the dynamical behaviors of five paradigmatic spiking neuron models and present recent literature studies on the topic, classifying the contributions based on the most-studied items. The aim of this review is to provide the reader with fundamental details related to spiking neurons from a dynamical systems point-of-view.
View Article and Find Full Text PDFThe future of engineering systems is based on the capability of integrating sensors, actuators, control systems and materials [...
View Article and Find Full Text PDFNon-Intrusive load monitoring (NILM) represents an emerging strategy based on the application of sevaral multidisciplinary topics [...
View Article and Find Full Text PDFRobotics and micromachines are challenging topics in engineering [...
View Article and Find Full Text PDFBackground: This review explores state-of-the-art teleoperated robots for medical ultrasound scan procedures, providing a comprehensive look including the recent trends arising from the COVID-19 pandemic.
Methods: Physicians' experience is included to indicate the importance of their role in the design of improved medical robots. From this perspective, novel classes of equipment for remote diagnostics based on medical robotics are discussed in terms of innovative engineering technologies.
Synchronization of chaotic dynamics can be pursued by means of different coupling strategies. Definitely, master-slave coupling represents one of the most adopted solutions, even if it presents some limitations due to the coupling term's selection strategy. In this paper, we investigate the role of different structures of coupling terms on the synchronization properties of master-slave chaotic system configurations.
View Article and Find Full Text PDFOptical remote sensors are nowadays ubiquitously used, thanks to unprecedented advances in the last decade in photonics, machine learning and signal processing tools. In this work we study experimentally the remote recovery of audio signals from the silent videos of the movement of optical speckle patterns. This technique can be used even when in between the source and the receiver there is a medium that does not allow for the propagation of sound waves.
View Article and Find Full Text PDFComplex patterns are commonly retrieved in spatially-extended systems formed by coupled nonlinear dynamical units. In particular, Turing patterns have been extensively studied investigating mathematical models pertaining to different fields, such as chemistry, physics, biology, mechanics, and electronics. In this paper, we focus on the emergence of Turing patterns in memristive cellular nonlinear networks by means of spatial pinning control.
View Article and Find Full Text PDFThe development of synchronization strategies for dynamical systems is an important research activity that can be applied in several different fields from locomotion control of multilimbed structures to secure communication. In the presence of chaotic systems, synchronization is more difficult to accomplish and there are different techniques that can be adopted. In this paper we considered a master-slave topology where the coupling mechanism is realized through a second-order linear dynamical system.
View Article and Find Full Text PDFIn this paper, we study synchronization in time-varying networks inherited by the Vicsek's model of self-propelled particles. In our model, each particle/agent moves in a two dimensional space according to the Vicsek's rules and is associated to a chaotic system. The dynamics of two oscillators are coupled with each other only when agents are at a distance less than an interaction radius.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
February 2015
Chimera states have been recently found in a variety of different coupling schemes and geometries. In most cases, the underlying coupling structure is considered to be static, while many realistic systems display significant temporal changes in the pattern of connectivity. In this work we investigate a time-varying network made of two coupled populations of Kuramoto oscillators, where the links between the two groups are considered to vary over time.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
October 2014
We study disease spreading in a system of agents moving in a space where the force of infection is not homogeneous. Agents are random walkers that additionally execute long-distance jumps, and the plane in which they move is divided into two regions where the force of infection takes different values. We show the onset of a local epidemic threshold and a global one and explain them in terms of mean-field approximations.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
September 2014
Chimera states, that is, dynamical regimes characterized by the existence of a symmetry-broken solution where a coherent domain and an incoherent one coexist, have been theoretically demonstrated and numerically found in networks of homogeneously coupled identical oscillators. In this work we experimentally investigate the behavior of a closed and an open chain of electronic circuits with neuron-like spiking dynamics and first neighbor connections. Experimental results show the onset of a regime that we call chimera states with quiescent and synchronous domains, where synchronization coexists with spatially patterned oscillation death.
View Article and Find Full Text PDFIn this report, we investigate dynamical robustness of a complex network to noise injected through one of its nodes. We focus on synchronization of coupled nonlinear systems and, as a special instance, we address the classical consensus protocol for linear integrators. We establish an exact closed-form expression of the synchronization error for the consensus protocol and an approximate result for chaotic units.
View Article and Find Full Text PDFIn this work, we experimentally investigate the robustness to noise of synchronization in all the four-nodes network motifs. The experimental setup consists of four Chua's circuits diffusively coupled in order to implement the six different undirected network motifs that can be obtained with four nodes. In this experimental setup, synchronization in the presence of noise injected in one of the network nodes is investigated and network motifs are compared in terms of the synchronization error obtained.
View Article and Find Full Text PDFIn this Letter, we introduce the concept of spatial pinning control for a network of mobile chaotic agents. In a planar space, N agents move as random walkers and interact according to a time-varying r-disk proximity graph. A control input is applied only to those agents which enter a given area, called control region.
View Article and Find Full Text PDFMemristors are gaining increasing attention as next generation electronic devices. They are also becoming commonly used as fundamental blocks for building chaotic circuits, although often arbitrary (typically piece-wise linear or cubic) flux-charge characteristics are assumed. In this paper, a chaotic circuit based on the mathematical realistic model of the HP memristor is introduced.
View Article and Find Full Text PDFIn this paper, chaos is applied to the control of moving robots in order to generate random-like trajectories needed in tasks such as exploration, scanning natural terrains or mapping of unknown environments. Synchronization between the robots of a team is achieved by exploiting the paradigm of mirror neurons, i.e.
View Article and Find Full Text PDFWe consider a set of mobile agents in a two dimensional space, each one of them carrying a chaotic oscillator, and discuss the related synchronization issues under the framework of time-variant networks. In particular, we show that, as far as the time scale for the motion of the agents is much shorter than that of the associated dynamical systems, the global behavior can be characterized by a scaled all-to-all Laplacian matrix, and the synchronization conditions depend on the agent density on the plane.
View Article and Find Full Text PDFPhilos Trans A Math Phys Eng Sci
February 2008
In this paper using a negative feedback scheme we study the problem of synchronizing two systems (each of them made of n independent chaotic circuits) through the transmission of a unique signal (i.e. a scalar variable).
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
January 2007
In this paper synchronization of multiplexed chaotic systems with smooth nonlinearities is studied. The strategy to establish if such synchronization is achievable is based on the master stability function approach and on the optimization of the coupling parameters. With this approach we are able to show that systems formed by three independent canonical chaotic circuits (i.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
September 2006
A dynamical network (consisting of a time-evolving wiring of interactions among a group of random walkers) is introduced to model the spread of an infectious disease in a population of mobile individuals. We investigate the main properties of this model, and show that peculiar features arise when individuals are allowed to perform long-distance jumps. Such peculiarities are captured and conveniently quantified by a series of appropriate parameters able to highlight the structural differences emerging in the networks when long-distance jumps are combined with local random walk processes.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
August 2006
In this paper a topic regarding the synchronization of chaotic systems is dealt with: the case of separation and synchronization of many chaotic signals generated by different chaotic circuits and combined together is examined. In particular, an observer based strategy has been adopted, and an approach for the simultaneous stabilization of many Luenberger observers has been investigated to face the problem of separation and synchronization. The design strategy is based on linear matrix inequalities (LMIs).
View Article and Find Full Text PDFIn this paper the dynamical network model of the interactions within a group of mobile robots is investigated and proposed as a possible strategy for controlling the robots without central coordination. Motivated by the results of the analysis of our simple model, we show that the system performance in the presence of noise can be improved by including long-range connections between the robots. Finally, a suitable strategy based on this model to control exploration and transport is introduced.
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