Vagner dos Santos

Dr. Vagner dos Santos

Ponta Grossa State University, Ponta Grossa, Paraná, Brazil
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orcid

Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 August 2018 in Chaos: An Interdisciplinary Journal of Nonlinear Science
Verified
Journal Article
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VSVagner dos Santos
Vagner dos Santos
JJJose Danilo Szezech Junior
Jose Danilo Szezech Junior
ABAntonio M. Batista
Antonio M. Batista
KIK. C. Iarosz
K. C. Iarosz
MBM. S. Baptista
M. S. Baptista
JKJürgen Kurths
Jürgen Kurths
We investigate the basin of attraction properties and its boundaries for chimera states in a circulant network of Hénon maps. It is known that coexisting basins of attraction lead to a hysteretic behaviour in the diagrams of the density of states as a function of a varying parameter. Chimera states, for which coherent and incoherent domains occur simultaneously, emerge as a consequence of the coexistence of basin of attractions for each state. Consequently, the distribution of chimera states can remain invariant by a parameter change, and it can also suffer subtle changes when one of the basins ceases to exist. A similar phenomenon is observed when perturbations are applied in the initial conditions. By means of the uncertainty exponent, we characterise the basin boundaries between the coherent and chimera states, and between the incoherent and chimera states. This way, we show that the density of chimera states can be not only moderately sensitive but also highly sensitive to initial conditions. This chimera’s dilemma is a consequence of the fractal and riddled nature of the basin boundaries.

1 August 2020 in Chaos: An Interdisciplinary Journal of Nonlinear Science
Verified
Journal Article
Closed access
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VSVagner dos Santos
Vagner dos Santos
FBFernando S. Borges
Fernando S. Borges
KIKelly C. Iarosz
Kelly C. Iarosz
ICIbere Luiz Caldas
Ibere Luiz Caldas
JJJose Danilo Szezech Junior
Jose Danilo Szezech Junior
ABAntonio M. Batista
Antonio M. Batista
Chimera states are spatiotemporal patterns in which coherent and incoherent dynamics coexist simultaneously. These patterns were observed in both locally and nonlocally coupled oscillators. We study the existence of chimera states in networks of coupled Rössler oscillators. The Rössler oscillator can exhibit periodic or chaotic behavior depending on the control parameters. In this work, we show that the existence of coherent, incoherent, and chimera states depends not only on the coupling strength, but also on the initial state of the network. The initial states can belong to complex basins of attraction that are not homogeneously distributed. Due to this fact, we characterize the basins by means of the uncertainty exponent and basin stability. In our simulations, we find basin boundaries with smooth, fractal, and riddled structures.

2 June 2022 in Mathematics
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Journal Article
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MMMuhammad Marwan
Muhammad Marwan
VSVagner dos Santos
Vagner dos Santos
MAMuhammad Zainul Abidin
Muhammad Zainul Abidin
AXAnda Xiong
Anda Xiong
This paper is divided into two main portions. First, we look at basins of attraction as a tool with a unique set of characteristics for discussing multistability and coexisting attractors in a gyrostat chaotic system. For the validation of coexisting attractors in different basins, several approaches such as bifurcation diagrams, Lyapunov exponents, and the Poincaré section are applied. The second half of the study synchronizes two mechanical chaotic systems using a novel controller, with gyrostat and quadrotor unmanned aerial vehicle (QUAV) chaotic systems acting as master and slave systems, respectively. The error dynamical system and the parameter updated law are built using Lyapunov’s theory, and it is discovered that under certain parametric conditions, the trajectories of the QUAV chaotic system overlap and begin to match the features of the gyrostat chaotic system.

1 August 2016 in Applied Mathematics and Computation
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Journal Article
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VSVagner dos Santos
Vagner dos Santos
JJJose Danilo Szezech Junior
Jose Danilo Szezech Junior
MBMurilo S. Baptista
Murilo S. Baptista
ABAntonio M. Batista
Antonio M. Batista
ICIberê L. Caldas
Iberê L. Caldas

14 February 2025 in Chaos, Solitons & Fractals
Verified
Journal Article
Closed access
VSVagner dos Santos
Vagner dos Santos
MSMatheus Rolim Sales
Matheus Rolim Sales
ICIbere Luiz Caldas
Ibere Luiz Caldas
RVRicardo Luiz Viana
Ricardo Luiz Viana
JJJose Danilo Szezech Junior
Jose Danilo Szezech Junior