Dokument-ID Dokumenttyp Verfasser/Autoren Herausgeber Haupttitel Abstract Auflage Verlagsort Verlag Erscheinungsjahr Seitenzahl Schriftenreihe Titel Schriftenreihe Bandzahl ISBN Quelle der Hochschulschrift Konferenzname Quelle:Titel Quelle:Jahrgang Quelle:Heftnummer Quelle:Erste Seite Quelle:Letzte Seite URN DOI Abteilungen OPUS4-51162 Wissenschaftlicher Artikel Agarwal, Ankit; Maheswaran, Rathinasamy; Marwan, Norbert; Caesar, Levke; Kurths, Jürgen Wavelet-based multiscale similarity measure for complex networks In recent years, complex network analysis facilitated the identification of universal and unexpected patterns in complex climate systems. However, the analysis and representation of a multiscale complex relationship that exists in the global climate system are limited. A logical first step in addressing this issue is to construct multiple networks over different timescales. Therefore, we propose to apply the wavelet multiscale correlation (WMC) similarity measure, which is a combination of two state-of-the-art methods, viz. wavelet and Pearson's correlation, for investigating multiscale processes through complex networks. Firstly we decompose the data over different timescales using the wavelet approach and subsequently construct a corresponding network by Pearson's correlation. The proposed approach is illustrated and tested on two synthetics and one real-world example. The first synthetic case study shows the efficacy of the proposed approach to unravel scale-specific connections, which are often undiscovered at a single scale. The second synthetic case study illustrates that by dividing and constructing a separate network for each time window we can detect significant changes in the signal structure. The real-world example investigates the behavior of the global sea surface temperature (SST) network at different timescales. Intriguingly, we notice that spatial dependent structure in SST evolves temporally. Overall, the proposed measure has an immense potential to provide essential insights on understanding and extending complex multivariate process studies at multiple scales. New York Springer 2018 12 The European physical journal : B, Condensed matter and complex systems 91 11 10.1140/epjb/e2018-90460-6 Institut für Physik und Astronomie OPUS4-46897 Wissenschaftlicher Artikel Zaikin, Alexey; Kurths, Jürgen Optimal length transportation hypothesis to model proteasome product size distribution This paper discusses translocation features of the 20S proteasome in order to explain typical proteasome length distributions. We assume that the protein transport depends significantly on the fragment length with some optimal length which is transported most efficiently. By means of a simple one-channel model, we show that this hypothesis can explain both the one- and the three-peak length distributions found in experiments. A possible mechanism of such translocation is provided by so-called fluctuation-driven transport. Dordrecht Springer 2006 13 Journal of biological physics : emphasizing physical principles in biological research ; an international journal for the formulation and application of mathematical models in the biological sciences 32 3-4 231 243 10.1007/s10867-006-9014-z Institut für Physik und Astronomie OPUS4-53918 Wissenschaftlicher Artikel Goswami, Bedartha; Boers, Niklas; Rheinwalt, Aljoscha; Marwan, Norbert; Heitzig, Jobst; Breitenbach, Sebastian Franz Martin; Kurths, Jürgen Abrupt transitions in time series with uncertainties Identifying abrupt transitions is a key question in various disciplines. Existing transition detection methods, however, do not rigorously account for time series uncertainties, often neglecting them altogether or assuming them to be independent and qualitatively similar. Here, we introduce a novel approach suited to handle uncertainties by representing the time series as a time-ordered sequence of probability density functions. We show how to detect abrupt transitions in such a sequence using the community structure of networks representing probabilities of recurrence. Using our approach, we detect transitions in global stock indices related to well-known periods of politico-economic volatility. We further uncover transitions in the El Niño-Southern Oscillation which coincide with periods of phase locking with the Pacific Decadal Oscillation. Finally, we provide for the first time an 'uncertainty-aware' framework which validates the hypothesis that ice-rafting events in the North Atlantic during the Holocene were synchronous with a weakened Asian summer monsoon. London Nature Publ. Group 2018 10 Nature Communications 9 10.1038/s41467-017-02456-6 Institut für Geowissenschaften OPUS4-10612 Wissenschaftlicher Artikel Thiel, Marco; Romano, Maria Carmen; Kurths, Jürgen; Rolfs, Martin; Kliegl, Reinhold Generating surrogates from recurrences In this paper, we present an approach to recover the dynamics from recurrences of a system and then generate (multivariate) twin surrogate (TS) trajectories. In contrast to other approaches, such as the linear-like surrogates, this technique produces surrogates which correspond to an independent copy of the underlying system, i.e. they induce a trajectory of the underlying system visiting the attractor in a different way. We show that these surrogates are well suited to test for complex synchronization, which makes it possible to systematically assess the reliability of synchronization analyses. We then apply the TS to study binocular fixational movements and find strong indications that the fixational movements of the left and right eye are phase synchronized. This result indicates that there might be only one centre in the brain that produces the fixational movements in both eyes or a close link between the two centres. 2008 Department Psychologie OPUS4-11950 Wissenschaftlicher Artikel Wu, Ye; Zhou, Changsong; Chen, Maoyin; Xiao, Jinghua; Kurths, Jürgen Human comment dynamics in on-line social systems Human comment is studied using data from 'tianya' which is one of the most popular on-line social systems in China. We found that the time interval between two consecutive comments on the same topic, called inter-event time, follows a power-law distribution. This result shows that there is no characteristic decay time on a topic. It allows for very long periods without comments that separate bursts of intensive comments. Furthermore, the frequency of a different ID commenting on a topic also follows a power-law distribution. It indicates that there are some "hubs" in the topic who lead the direction of the public opinion. Based on the personal comments habit, a model is introduced to explain these phenomena. The numerical simulations of the model fit well with the empirical results. Our findings are helpful for discovering regular patterns of human behavior in on-line society and the evolution of the public opinion on the virtual as well as real society. 2010 10.1016/j.physa.2010.08.049 Institut für Physik und Astronomie OPUS4-11962 Wissenschaftlicher Artikel Winterhalder, Matthias; Schelter, B; Kurths, Jürgen; Schulze-Borthage, A; Timmer, Jens Sensitivity and specificity of coherence and phase synchronization analysis In this Letter, we show that coherence and phase synchronization analysis are sensitive but not specific in detecting the correct class of underlying dynamics. We propose procedures to increase specificity and demonstrate the power of the approach by application to paradigmatic dynamic model systems. (c) 2006 Elsevier B.V. All rights reserved 2006 10.1016/j.physleta.2006.03.018 Institut für Physik und Astronomie OPUS4-12099 Wissenschaftlicher Artikel Dana, Syamal Kumar; Blasius, Bernd; Kurths, Jürgen Experimental evidence of anomalous phase synchronization in two diffusively coupled Chua oscillators We study the transition to phase synchronization in two diffusively coupled, nonidentical Chua oscillators. In the experiments, depending on the used parameterization, we observe several distinct routes to phase synchronization, including states of either in-phase, out-of-phase, or antiphase synchronization, which may be intersected by an intermediate desynchronization regime with large fluctuations of the frequency difference. Furthermore, we report the first experimental evidence of an anomalous transition to phase synchronization, which is characterized by an initial enlargement of the natural frequency difference with coupling strength. This results in a maximal frequency disorder at intermediate coupling levels, whereas usual phase synchronization via monotonic decrease in frequency difference sets in only for larger coupling values. All experimental results are supported by numerical simulations of two coupled Chua models 2006 10.1063/1.2197168 Institut für Physik und Astronomie OPUS4-12045 Wissenschaftlicher Artikel Vasconcelos, D. B.; Lopes, S. R.; Viana, R. L.; Kurths, Jürgen Spatial recurrence plots We propose an extension of the recurrence plot concept to perform quantitative analyzes of roughness and disorder of spatial patterns at a fixed time. We introduce spatial recurrence plots (SRPs) as a graphical representation of the pointwise correlation matrix, in terms of a two-dimensional spatial return plot. This technique is applied to the study of complex patterns generated by coupled map lattices, which are characterized by measures of complexity based on SRPs. We show that the complexity measures we propose for SRPs provide a systematic way of investigating the distribution of spatially coherent structures, such as synchronization domains, in lattice profiles. This approach has potential for many more applications, e.g., in surface roughness analyzes 2006 10.1103/Physreve.73.056207 Institut für Physik und Astronomie OPUS4-12503 Wissenschaftlicher Artikel Baptista, Murilo da Silva; Pereira, Tiago; Kurths, Jürgen Upper bounds in phase synchronous weak coherent chaotic attractors An approach is presented for coupled chaotic systems with weak coherent motion, from which we estimate the upper bound value for the absolute phase difference in phase synchronous states. This approach shows that synchronicity in phase implies synchronicity in the time of events, a characteristic explored to derive an equation to detect phase synchronization, based on the absolute difference between the time of these events. We demonstrate the potential use of this approach for the phase coherent and the funnel attractor of the Rossler system, as well as for the spiking/bursting Rulkov map. 2006 10.1016/j.physd.2006.02.007 Institut für Physik und Astronomie OPUS4-13471 Wissenschaftlicher Artikel Baptista, Murilo da Silva; Pereira, Tiago; Sartorelli, J. C.; Caldas, Ibere Luiz; Kurths, Jürgen Non-transitive maps in phase synchronization Concepts from Ergodic Theory are used to describe the existence of special non-transitive maps in attractors of phase synchronous chaotic oscillators. In particular, it is shown that, for a class of phase-coherent oscillators, these special maps imply phase synchronization. We illustrate these ideas in the sinusoidally forced Chua's circuit and two coupled Rossler oscillators. Furthermore, these results are extended to other coupled chaotic systems. In addition, a phase for a chaotic attractor is defined from the tangent vector of the flow. Finally, it is discussed how these maps can be used for the real-time detection of phase synchronization in experimental systems. (c) 2005 Elsevier B.V. All rights reserved 2005 Institut für Physik und Astronomie