Reader
- About
-
- Email Address
- murilo.baptista@abdn.ac.uk
- Telephone Number
- +44 (0)1224 272489
- Office Address
University of Aberdeen
Institute for Complex Systems and Mathematical Biology
Meston Building, Meston Walk
Aberdeen AB24 3UE
- School/Department
- School of Natural and Computing Sciences
Biography
Since 2014, I am a Reader of the University of Aberdeen, having joined it in 2009 as a Senior Lecturer. Before that, I worked as a postdoc, guest scientist, or guest assistant professor at 5 Universities and Institutes in USA, Brazil, Germany, and Portugal. I have interest in understanding the relationship among function (e.g., information, collective behaviour and synchronisation) and structure in large networked complex systems for its posterior modelling, having contributed to works in neuroscience, smart engineering systems, and sustainability of the Earth. My work is supported by analytical developments, but I also rely on the analysis and modelling of data using techniques from data sciences, nonlinear time-series analysis, and machine learning. I am a leading scientist in the area of chaos-based communication, where I am working to show that chaos offers alternative technologies for efficiently smart (and secure) wireless communication systems.
- Research
-
Research Overview
I have interest in understanding the relationship among function (e.g., information, collective behaviour and synchronisation) and structure in large networked complex systems for its posterior modelling, having contributed to works in neuroscience, smart engineering systems, and sustainability of the Earth. My work is supported by analytical developments, but I also rely on the analysis and modelling of data using techniques from data sciences, nonlinear time-series analysis, and machine learning. I am a leading scientist in the area of chaos-based communication, where I am working to show that chaos offers alternative technologies for efficiently smart (and secure) wireless communication systems.
Research Areas
Accepting PhDs
I am currently accepting PhDs in Physics, Maths, Engineering.
Please get in touch if you would like to discuss your research ideas further.
Research Specialisms
- Mathematical Modelling
- Applied Mathematics
- Dynamics
- Information Technology
- Neural Computing
Our research specialisms are based on the Higher Education Classification of Subjects (HECoS) which is HESA open data, published under the Creative Commons Attribution 4.0 International licence.
Current Research
I am working to understand optimal configuration to communicate wirelessly with chaos in the air and in space, to model synapses and their information capacity, predict degradation in vessels, to understand how synchronisation emerges in networks with connections of higher order, to model how arguments in a networks of agents predominates, to understand the causal relationship of socio and economic variables in Brazil, to explain the topological changes suffered in the brain of patients that have undergone brain surgeries due to tumours.
Past Research
During my PhD, we discovered that the driven Chua’s chaotic circuit presented a transition to chaos via destruction of a two-frequency torus. Though this route was known, the description of topological changes suffered by the chaotic attractor was not. Later on, I work to define the phase of chaotic oscillators. Though the phase of a periodic signal is a well-known quantity, for chaotic trajectories, it is not. Our work has proposed a mathematical framework to define and measure it.
To secure communication systems based on chaos, the chaotic wave signal encoding information should not be transmitted. Instead, one could transmit the trajectory’s Poincaré first return times (PFRT). This understanding resulted in the cipher today one of the founding references for the area of chaos-based cryptography. We have proved (see http://hdl.handle.net/10216/65184) a conjecture that the distribution of PFRTs can be analytically calculated by the eigenvalues of the unstable periodic orbits of the chaotic attractor, and shown that a very important and popular quantity to characterise chaotic behaviour - the Kolmogorov-Sinai entropy – can be estimated from PFRTs.
Typically, chaotic behaviour in a nonlinear system is replaced by periodic behaviour even when arbitrarily small parameter alterations are made. I worked on experiments to demonstrate this and validate works that explain why periodic behaviour is ubiquitous in nature, came in Ref. [42,90].
My work in neural networks with neurons connected by both electrical and chemical synapses has provided a rigorous ground to explain the regulatory effect that electrical synapses have in the brain. The study of such networks, known as multiplex networks, only became a topic of attention by the scientific community by 2013. We have proposed a formula for the mutual information in terms of Lyapunov exponents (that quantify chaos) and used to provide support for the Infomax theory that suggests that the brain evolve by maximising information. We have discovered the phenomenon of Collective Almost Synchronization, ubiquitous in complex networks, and that has been shown to be crucial for the chaos enhancement of machine learning methods to model and predict EEG signals. I have also shown that the cause-effect relationship between variables, or causality (and that is usually characterised by temporal quantities), is a spatial-temporal phenomenon. Finally, we have shown that a power grid without control systems can be designed to be reliable by properly connecting generators and consumers.
- Publications
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Page 2 of 2 Results 101 to 171 of 171
Natural synchronization in power-grids with anti-correlated units
Communications in Nonlinear Science & Numerical Simulation, vol. 18, no. 4, pp. 1035-1046Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.cnsns.2012.08.030
Secure information transfer based on computing reservoir
Physics Letters A, vol. 377, no. 10-11, pp. 760-765Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physleta.2013.01.021
Structure and function in flow networks
Europhysics Letters, vol. 101, no. 6, 68001Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1209/0295-5075/101/68001
- [OPEN ACCESS] http://aura.abdn.ac.uk/bitstream/2164/3378/1/Structure_and_function_in_flow.pdf
- [ONLINE] View publication in Scopus
Synthetic aperture sonar images segmentation using dynamical modeling analysis
Revista Brasileira de Geofisica, vol. 31, no. 3, pp. 455-462Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.22564/rbgf.v31i3.315
- [ONLINE] View publication in Scopus
Synthetic aperture sonar images segmentation using dynamical modelling analysis
Revista Brasileira de Geofísica, vol. 31, no. 3, pp. 455-462Contributions to Journals: ArticlesCollective almost synchronisation in complex networks
PloS ONE, vol. 7, no. 11, e48118Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1371/journal.pone.0048118
- [OPEN ACCESS] http://aura.abdn.ac.uk/bitstream/2164/3515/1/Coolective_almost.pdf
Mutual information rate and bounds for it
PloS ONE, vol. 7, no. 10, e46745Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1371/journal.pone.0046745
- [OPEN ACCESS] http://aura.abdn.ac.uk/bitstream/2164/3569/1/Mutual_information.pdf
Fundamentals of a classical chaos-based cryptosystem with some quantum cryptography features
International Journal of Bifurcation and Chaos, vol. 22, no. 10, 1250243Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1142/S0218127412502434
Uncovering missing symbols in communication with filtered chaotic signals
International Journal of Bifurcation and Chaos, vol. 22, no. 8, 1250199Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1142/S0218127412501994
Active networks that maximize the amount of information transmission
International Journal of Bifurcation and Chaos, vol. 22, no. 2, 1230008Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1142/S021812741230008X
How complex a dynamical network can be?
Physics Letters A, vol. 375, no. 10, pp. 1309-1318Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physleta.2011.01.054
Density of first Poincare returns, periodic orbits, and Kolmogorov-Sinai entropy
Communications in Nonlinear Science & Numerical Simulation, vol. 16, no. 2, pp. 863-875Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.cnsns.2010.05.018
Density of first Poincaré returns, periodic orbits, and Kolmogorov–Sinai entropy
Communications in Nonlinear Science & Numerical Simulation, vol. 16, no. 2, pp. 863 -875Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.cnsns.2010.05.018
Abundance of stable periodic behavior in a Red Grouse population model with delay: A consequence of homoclinicity
Chaos, vol. 20, no. 4, 045117Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.3527032
Combined effect of chemical and electrical synapses in Hindmarsh-Rose neural networks on synchronization and the rate of information
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 82, no. 3, pp. 036203Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.82.036203
Kolmogorov-Sinai entropy from recurrence times
Physics Letters A, vol. 374, no. 9, pp. 1135-1140Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physleta.2009.12.057
Dynamical estimates of chaotic systems from Poincaré recurrences
Chaos, vol. 19, no. 4, pp. 1-10Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.3263943
A Scenario for torus T2 destruction via a global bifurcation
Chaos, Solitons & Fractals, vol. 39, no. 5, pp. 2198-2210Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.chaos.2007.06.115
Experimental identification of chaotic fibers
Chaos, Solitons & Fractals, vol. 39, no. 1, pp. 9-16Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.chaos.2007.01.131
The staircase structure of the Southern Brazilian Continental Shelf
Mathematical Problems in Engineering, vol. 2009, 624861Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1155/2009/624861
- [OPEN ACCESS] http://aura.abdn.ac.uk/bitstream/2164/4906/1/baptista_MPE2009.pdf
Transmission of information and synchronization in a pair of coupled chaotic circuits: An experimental overview
The European Physical Journal. Special Topics, vol. 165, no. 1, pp. 119-128Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1140/epjst/e2008-00855-y
Finding quasi-optimal network topologies for information transmission in active networks
PloS ONE, vol. 3, no. 10, e3479Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1371/journal.pone.0003479
- [OPEN ACCESS] http://aura.abdn.ac.uk/bitstream/2164/3543/1/Finding_Quasi.pdf
Network mutual information and synchronization under time transformations
New Journal of Physics, vol. 10, pp. -Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1088/1367-2630/10/8/083003
Synchronization and information transmission in spatio-temporal networks of deformable units
Pramana, vol. 70, no. 6, pp. 1063-1076Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1007/s12043-008-0111-3
Phase and average period of chaotic oscillators(vol 362, pg 159, 2007): Erratum
Physics Letters A, vol. 372, no. 13, pp. 2339-2340Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physleta.2007.09.077
Experimental observation of a complex periodic window
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 77, no. 3, 037202Contributions to Journals: Articles- [ONLINE] http://link.aps.org/doi/10.1103/PhysRevE.77.037202
- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.77.037202
Reconstruction of eye movements during blinks
Chaos, vol. 18, 013126Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.2890843
Transmission of information in active networks
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 77, no. 2, 026205Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.77.026205
Onset of phase synchronization in neurons with chemical synapse
International Journal of Bifurcation and Chaos, vol. 17, no. 10, pp. 3545-3549Contributions to Journals: ArticlesGeneral framework for phase synchronization through localized sets
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 75, no. 2, 026216Contributions to Journals: Articles- [ONLINE] http://link.aps.org/doi/10.1103/PhysRevE.75.026216
- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.75.026216
Phase and average period of chaotic oscillators
Physics Letters A, vol. 362, no. 2-3, pp. 159-165Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physleta.2006.09.099
Detecting phase synchronization by localized maps: Application to neural networks
Europhysics Letters, vol. 77, no. 4, 40006Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1209/0295-5075/77/40006
Shilnikov homoclinic orbit bifurcations in the Chua's circuit
Chaos, vol. 16, no. 4Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.2401060
Dynamically Multilayered Visual System of the Multifractal Fly
Physical Review Letters, vol. 97, no. 17Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevLett.97.178102
Upper bounds in phase synchronous weak coherent chaotic attractors
Physica. D, Nonlinear Phenomena, vol. 216, no. 2, pp. 260-268Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physd.2006.02.007
Information transmission in phase synchronous chaotic arrays
Chinese Physics Letters, vol. 23, no. 3, pp. 560-563Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1088/0256-307X/23/3/010
Global bifurcation destroying the experimental torus T-2
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 73, no. 1, 017201Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.73.017201
Non-transitive maps in phase synchronization
Physica. D, Nonlinear Phenomena, vol. 212, no. 3-4, pp. 216-232Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physd.2005.10.003
Chaotic channel
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 72, no. 4 Part 2, 045202Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.72.045202
Basic structures of the Shilnikov homoclinic bifurcation scenario
Chaos, vol. 15, no. 3, 033112Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.2031978
Poincare Recurrence and Measure of Hyperbolic and Nonhyperbolic Chaotic Attractors
Physical Review Letters, vol. 95, no. 9, pp. 094101-1 - 094101-4Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevLett.95.094101
Conditional targeting for communication
Chaos, Solitons & Fractals, vol. 21, no. 5, pp. 1271-1280Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.chaos.2003.12.048
Irrational phase synchronization
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, vol. 69, no. 5, 056228Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.69.056228
Phase synchronization and invariant measures in sinusoidally perturbed chaotic systems
Shock Compression of Condensed Matter, vol. 742, pp. 325-329Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.1846493
Homoclinic orbits in a piecewise system and their relation with invariant sets
Physica. D, Nonlinear Phenomena, vol. 186, no. 3-4, pp. 133-147Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/j.physd.2003.08.002
Controlling transient dynamics to communicate with homoclinic chaos
Chaos, vol. 13, no. 3, pp. 921-925Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.1602591
Periodic driving of plasma turbulence
Physics of Plasmas, vol. 10, no. 5, pp. 1283-1290Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.1561612
Phase synchronization in the perturbed Chua circuit
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, vol. 67, no. 5, 056212Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.67.056212
Stock market dynamics
Physica. A, Statistical Mechanics and its Applications, vol. 312, no. 3-4, pp. 539-564Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0378-4371(02)00847-6
Dealing with final state sensitivity for synchronous communication
Physica. A, Statistical Mechanics and its Applications, vol. 308, no. 1-4, pp. 101-112Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0378-4371(02)00572-1
Information transfer in chaos-based communication
Physical Review. E, Statistical, Nonlinear and Soft Matter Physics, vol. 65, no. 5Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.65.055201
Statistics of plasma fluctuations in runaway discharges in TCABR tokamak
Brazilian Journal of Physics, vol. 32, no. 1, pp. 95-99Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1590/S0103-97332002000100018
Statistics of turbulence induced by magnetic field
Brazilian Journal of Physics, vol. 32, no. 1, pp. 85-88Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1590/S0103-97332002000100016
Onset of symmetric plasma turbulence
Physica. A, Statistical Mechanics and its Applications, vol. 301, no. 1-4, pp. 150-162Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0378-4371(01)00395-8
Recurrence in plasma edge turbulence
Physics of Plasmas, vol. 8, no. 10, pp. 4455-4462Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.1401117
Statistics of plasma edge turbulence in tokamaks
American Institute of Physics Conference Proceedings, vol. 563, no. 1, pp. 221-226Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.1374912
Low-dimensional dynamics in observables from complex and higher-dimensional systems
Physica. A, Statistical Mechanics and its Applications, vol. 287, no. 1-2, pp. 91-99Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0378-4371(00)00448-9
Integrated chaotic communication scheme
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, vol. 62, no. 4, pp. 4835-4845Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.62.4835
On the stock market recurrence
Physica. A, Statistical Mechanics and its Applications, vol. 284, no. 1-4, pp. 348-354Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0378-4371(00)00226-0
Communication through chaotic modeling of languages
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, vol. 61, no. 4, pp. 3590-3600Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.61.3590
Control of shipboard cranes
Chapters in Books, Reports and Conference Proceedings: Conference ProceedingsType-II intermittency in the driven Double Scroll Circuit
Physica. D, Nonlinear Phenomena, vol. 132, no. 3, pp. 325-338Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0167-2789(99)00037-8
Dynamics of the two-frequency torus breakdown in the driven double scroll circuit
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, vol. 58, no. 4, pp. 4413-4420Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1103/PhysRevE.58.4413
Phase-locking and bifurcations of the sinusoidally-driven double scroll circuit
Nonlinear Dynamics, vol. 17, no. 2, pp. 119-139Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1023/A:1008284804398
Interior crises in a dripping faucet experiment
Physical Review. E, Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics, vol. 58, no. 3, pp. 4009-4011Contributions to Journals: ArticlesTargeting applying epsilon-bounded orbit correction perturbations
International Journal of Bifurcation and Chaos, vol. 8, no. 7, pp. 1575-1584Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1142/S0218127498001224
Cryptography with chaos
Physics Letters A, vol. 240, no. 1-2, pp. 50-54Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1016/S0375-9601(98)00086-3
Easy-to-implement method to target nonlinear systems
Chaos, vol. 8, no. 1, pp. 290-299Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1063/1.166309
The parameter space structure of the kicked logistic map and its stability
International Journal of Bifurcation and Chaos, vol. 7, no. 2, pp. 447-457Contributions to Journals: Articles- [ONLINE] DOI: https://doi.org/10.1142/S0218127497000327
Dynamics of the kicked logistic map
Chaos, Solitons & Fractals, vol. 7, no. 3, pp. 325-336Contributions to Journals: ArticlesControl of Trajectories of the Kicked Logistic Map
Chapters in Books, Reports and Conference Proceedings: Conference Proceedings