@article{ZaksParkKurths2000,
  author    = {Zaks, Michael A. and Park, Eun Hyoung and Kurths, J{\"u}rgen},
  title     = {On phase synchronization by periodic force in chaotic oscillators with saddle equilibria},
  year      = {2000},
  language  = {en}
}
@article{HainzlZoellerKurths2000,
  author    = {Hainzl, Sebastian and Z{\"o}ller, Gert and Kurths, J{\"u}rgen},
  title     = {Self-organization of spatio-temporal earthquake clusters},
  year      = {2000},
  language  = {en}
}
@article{BoccalettiValladaresKurths2000,
  author    = {Boccaletti, Stefano and Valladares, D. L. and Kurths, J{\"u}rgen},
  title     = {Synchronization of chaotic structurally nonequivalent systems},
  year      = {2000},
  language  = {en}
}
@article{ZiehmannSmithKurths2000,
  author    = {Ziehmann, Christine and Smith, Leonard A. and Kurths, J{\"u}rgen},
  title     = {Localized Lyapunov exponents and the prediction of predictability},
  year      = {2000},
  language  = {en}
}
@article{AnishchenkoKopeikinKurths2000,
  author    = {Anishchenko, Vadim S. and Kopeikin, A. S. and Kurths, J{\"u}rgen},
  title     = {Studying hyperbolicity in chaotic systems},
  year      = {2000},
  language  = {en}
}
@article{HainzlZoellerKurthsetal.2000,
  author    = {Hainzl, Sebastian and Z{\"o}ller, Gert and Kurths, J{\"u}rgen and Zschau, Jochen},
  title     = {Seismic quiescence as an indicator for large earthquakes in a system of self-organized criticality},
  year      = {2000},
  language  = {en}
}
@article{WesselVossMalbergetal.2000,
  author    = {Wessel, Niels and Voss, Andreas and Malberg, Hagen and Ziehmann, Christine and Voss, Henning U. and Schirdewan, Alexander and Meyerfeldt, Udo and Kurths, J{\"u}rgen},
  title     = {Nonlinear analysis of complex phenomena in cardiological data},
  year      = {2000},
  abstract  = {The main intention of this contribution is to discuss different nonlinear approaches to heart rate and blood pressure variability analysis for a better understanding of the cardiovascular regulation. We investigate measures of complexity which are based on symbolic dynamics, renormalised entropy and the finite time growth rates. The dual sequence method to estimate the baroreflex sensitivity and the maximal correlation method to estimate the nonlinear coupling between time series are employed for analysing bivariate data. The latter appears to be a suitable method to estimate the strength of the nonlinear coupling and the coupling direction. Heart rate and blood pressure data from clinical pilot studies and from very large clinical studies are analysed. We demonstrate that parameters from nonlinear dynamics are useful for risk stratification after myocardial infarction, for the prediction of life-threatening cardiac events even in short time series, and for modelling the relationship between heart rate and blood pressure regulation. These findings could be of importance for clinical diagnostics, in algorithms for risk stratification, and for therapeutic and preventive tools of next generation implantable cardioverter defibrillators.},
  language  = {en}
}
@article{WesselSchumannWesseletal.2000,
  author    = {Wessel, Niels and Schumann, Agnes and Wessel, Niels and Schumann, Agnes and Schirdewan, Alexander and Voss, Andreas and Kurths, J{\"u}rgen},
  title     = {Entropy measures in heart rate variability data},
  year      = {2000},
  language  = {en}
}
@article{MarwanSchwarzKurthsetal.2000,
  author    = {Marwan, Norbert and Schwarz, Udo and Kurths, J{\"u}rgen and Strecker, Manfred},
  title     = {ENSO Impact on landslide generation in northwestern Argentina},
  issn      = {1029-7006},
  year      = {2000},
  abstract  = {Climatic changes are of major importance in landslide generation in the Argentine Andes. Increased humidity as a potential influential factor was inferred from the temporal clustering of landslide deposits during a period of significantly wetter climate, 30,000 years ago. A change in seasonality was tested by comparing past (inferred from annual-layered lake deposits, 30,000 years old) and modern (present-day observations) precipitation changes. Quantitative analysis of cross recurrence plots were developed to compare the influence of the El Nino/Southern Oscillation (ENSO) on present and past rainfall variations. This analysis has shown the stronger influence of NE trades in the location of landslide deposits in the intra-andean basin and valleys, what caused a higher contrast between summer and winter rainfall and an increasing of precipitation in La Nina years. This is believed to reduce thresholds for landslide generation in the arid to semiarid intra-andean basins and valleys.},
  language  = {en}
}
@article{LandaZaikinKurths2000,
  author    = {Landa, Polina S. and Zaikin, Alexei A and Kurths, J{\"u}rgen},
  title     = {On noise-induced transitions in nonlinear oscillators},
  isbn      = {3-540- 41074-0},
  year      = {2000},
  language  = {en}
}
@article{LandaZaikinUshakovetal.2000,
  author    = {Landa, Polina S. and Zaikin, Alexei A. and Ushakov, V. G. and Kurths, J{\"u}rgen},
  title     = {Influence of additive noise on transitions in nonlinear systems},
  year      = {2000},
  abstract  = {The effect of additive noise on transitions in nonlinear systems far from equilibrium is studied. It is shown that additive noise in itself can induce a hidden phase transition, which is similar to the transition induced by multiplicative noise in a nonlinear oscillator [P. Landa and A. Zaikin, Phys. Rev. E 54, 3535 (1996)]. Investigation of different nonlinear models that demonstrate phase transitions induced by multiplicative noise shows that the influence of additive noise upon such phase transitions can be crucial: additive noise can either blur such a transition or stabilize noise-induced oscillations.},
  language  = {en}
}
@article{PopovychMaistrenkoMosekildeetal.2000,
  author    = {Popovych, Orest and Maistrenko, Yu and Mosekilde, Erik and Pikovskij, Arkadij and Kurths, J{\"u}rgen},
  title     = {Transcritical loss of synchronization in coupled chaotic systems},
  year      = {2000},
  language  = {en}
}
@article{ZaikinKurthsSchimanskyGeier2000,
  author    = {Zaikin, Alexei A. and Kurths, J{\"u}rgen and Schimansky-Geier, Lutz},
  title     = {Doubly stochastic resonance},
  year      = {2000},
  abstract  = {We report the effect of doubly stochastic resonance which appears in nonlinear extended systems if the influence of noise is twofold: A multiplicative noise induces bimodality of the mean field of the coupled network and an independent additive noise governs the dynamic behavior in response to small periodic driving. For optimally selected values of the additive noise intensity stochastic resonance is observed, which is manifested by a maximal coherence between the dynamics of the mean field and the periodic input. Numerical simulations of the signal-to-noise ratio and theoretical results from an effective two state model are in good quantitative agreement.},
  language  = {en}
}
@article{WesselVossKurthsetal.2000,
  author    = {Wessel, Niels and Voss, Andreas and Kurths, J{\"u}rgen and Schirdewan, Alexander and Hnatkova, Katarina and Malik, Marek},
  title     = {Evaluation of renormalised entropy for risk stratification using heart rate variability data},
  year      = {2000},
  abstract  = {Standard time and frequency parameters of heart rate variability (HRV) describe only linear and periodic behaviour, whereas more complex relationships cannot be recognised. A method that may be capable of assessing more complex properties is the non-linear measure of 'renormalised entropy.' A new concept of the method, RE(AR), has been developed, based on a non-linear renormalisation of autoregressive spectral distributions. To test the hypothesis that renormalised entropy may improve the result of high-risk stratification after myocardial infarction, it is applied to a clinical pilot study (41 subjects) and to prospective data of the St George's Hospital post- infarction database (572 patients). The study shows that the new RE(AR) method is more reproducible and more stable in time than a previously introduced method (p<0.001). Moreover, the results of the study confirm the hypothesis that on average, the survivors have negative values of RE(AR) (-0.11+/-0.18), whereas the non-survivors have positive values (0.03+/-0.22, p<0.01). Further, the study shows that the combination of an HRV triangular index and RE(AR) leads to a better prediction of sudden arrhythmic death than standard measurements of HRV. In summary, the new RE(AR) method is an independent measure in HRV analysis that may be suitable for risk stratification in patients after myocardial infarction.},
  language  = {en}
}
@article{TimmerSchwarzVossetal.2000,
  author    = {Timmer, Jens and Schwarz, Udo and Voss, Henning U. and Wardinski, Ingo and Belloni, Tomaso and Hasinger, G{\"u}nther and VanDerKlis, Michael and Kurths, J{\"u}rgen},
  title     = {Linear and Nonlinear Time Series Analysis of the Black Hole Candidate Cygnus X-1},
  year      = {2000},
  abstract  = {We analyze the variability in the x-ray lightcurves of the black hole candidate Cygnus X-1 by linear and nonlinear time series analysis methods. While a linear model describes the overall second order properties of the observed data well, surrogate data analysis reveals a significant deviation from linearity. We discuss the relation between shot noise models usually applied to analyze these data and linear stochastic autoregressive models. We debate statistical and interpretational issues of surrogate data testing for the present context. Finally, we suggest a combination of tools from linear and nonlinear time series analysis methods as a procedure to test the predictions of astrophysical models on observed data.},
  language  = {en}
}
@article{WesselZiehmannKurthsetal.2000,
  author    = {Wessel, Niels and Ziehmann, Christine and Kurths, J{\"u}rgen and Meyerfeldt, Udo and Schirdewan, Alexander and Voss, Andreas},
  title     = {Short-term forecasting of life-threatening cardiac arrhythmias based on symbolic dynamics and finite-time growth rates},
  year      = {2000},
  abstract  = {Ventricular tachycardia or fibrillation (VT-VF) as fatal cardiac arrhythmias are the main factors triggering sudden cardiac death. The objective of this study is to find early signs of sustained VT-VF in patients with an implanted cardioverter-defibrillator (ICD). These devices are able to safeguard patients by returning their hearts to a normal rhythm via strong defibrillatory shocks; additionally, they store the 1000 beat-to-beat intervals immediately before the onset of a life-threatening arrhythmia. We study these 1000 beat-to-beat intervals of 17 chronic heart failure ICD patients before the onset of a life-threatening arrhythmia and at a control time, i.e., without a VT-VF event. To characterize these rather short data sets, we calculate heart rate variability parameters from the time and frequency domain, from symbolic dynamics as well as the finite-time growth rates. We find that neither the time nor the frequency domain parameters show significant differences between the VT-VF and the control time series. However, two parameters from symbolic dynamics as well as the finite-time growth rates discriminate significantly both groups. These findings could be of importance in algorithms for next generation ICD's to improve the diagnostics and therapy of VT-VF.},
  language  = {en}
}
@article{PikovskijRosenblumKurths2000,
  author    = {Pikovskij, Arkadij and Rosenblum, Michael and Kurths, J{\"u}rgen},
  title     = {Phase synchronization in regular and chaotic systems},
  issn      = {0218-1274},
  year      = {2000},
  language  = {en}
}
@article{ZaikinKurths2000,
  author    = {Zaikin, Alexei A. and Kurths, J{\"u}rgen},
  title     = {Additive noise and noise-induced nonequilibrium phase transitions},
  isbn      = {1-563-96826-6},
  year      = {2000},
  language  = {en}
}
@article{BeimGrabenSaddySchlesewskyetal.2000,
  author    = {Beim Graben, Peter and Saddy, Douglas and Schlesewsky, Matthias and Kurths, J{\"u}rgen},
  title     = {Symbolic dynamics of event-related brain potentials},
  year      = {2000},
  language  = {en}
}
@article{KrampeEngbertKliegletal.2000,
  author    = {Krampe, Ralf-Thomas and Engbert, Ralf and Kliegl, Reinhold and Kurths, J{\"u}rgen},
  title     = {Koordination und Synchronisation der H{\"a}nde beim rhythmischen Timing},
  year      = {2000},
  language  = {de}
}
@unpublished{GuastiEngbertKrampeetal.2000,
  author    = {Guasti, Giovanna and Engbert, Ralf and Krampe, Ralf T. and Kurths, J{\"u}rgen},
  title     = {Phase transitions, complexity, and stationarity in the production of polyrhythms},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-14933},
  year      = {2000},
  abstract  = {Contents: 1 Introduction 2 Experiment 3 Data 4 Symbolic dynamics 4.1 Symbolic dynamics as a tool for data analysis 4.2 2-symbols coding 4.3 3-symbols coding 5 Measures of complexity 5.1 Word statistics 5.2 Shannon entropy 6 Testing for stationarity 6.1 Stationarity 6.2 Time series of cycle durations 6.3 Chi-square test 7 Control parameters in the production of rhythms 8 Analysis of relative phases 9 Discussion 10 Outlook},
  language  = {en}
}