Refine
Year of publication
Document Type
- Article (287)
- Postprint (11)
- Preprint (9)
- Monograph/Edited Volume (8)
- Other (1)
Keywords
- Complex networks (5)
- Event synchronization (4)
- precipitation (3)
- synchronization (3)
- Amazon rainforest (2)
- Extreme rainfall (2)
- Synchronization (2)
- bifurcations (2)
- channel (2)
- classification (2)
- climate networks (2)
- complex networks (2)
- diffusion (2)
- droughts (2)
- events (2)
- identifying influential nodes (2)
- models (2)
- prediction (2)
- rainfall (2)
- space-dependent diffusivity (2)
- streamflow (2)
- 3D medical image analysis (1)
- African climate (1)
- Algebraic geometry (1)
- Anisotropy (1)
- Baiu (1)
- Bifurcation parameters (1)
- Biomass (1)
- Calvin cycle (1)
- Chaotic System (1)
- Cold air surges (1)
- Complex network (1)
- Convective storms (1)
- Dominant link directions (1)
- EEG (1)
- Escherichia-coli (1)
- Extreme events (1)
- Extreme precipitation (1)
- Holocene (1)
- Hypothesis Test (1)
- India (1)
- Indian monsoon (1)
- Indian summer monsoon (1)
- Isochrones (1)
- K-means technique (1)
- Lacunarity (1)
- Mesoscale systems (1)
- Multistationarity (1)
- Nonlinear time series (1)
- North-Atlantic climate (1)
- Partial wavelet coherence (1)
- Phase Synchronization (1)
- Planetary Rings (1)
- Plio-Pleistocene (1)
- Precipitation (1)
- Precipitation events (1)
- Rainfall (1)
- Rainfall network (1)
- Rainfall patterns (1)
- Recurrence plots (1)
- Regime shifts (1)
- Regionalization (1)
- Self-organizing map (1)
- South American monsoon system (1)
- Statistical and Nonlinear Physics (1)
- Subtropical cyclones (1)
- Surrogate Data (1)
- Teleconnection patterns (1)
- Thermoacoustic instability (1)
- Time-varying Delay (1)
- Tropical storms (1)
- Ungauged catchments (1)
- Wavelet power spectrum (1)
- Wavelets (1)
- Z-P approach (1)
- algorithms (1)
- anatomical connectivity (1)
- bifurcation analysis (1)
- climate-driven evolution (1)
- cluster-analysis (1)
- coherence (1)
- complex systems (1)
- cortical network (1)
- decomposition (1)
- desynchronization (1)
- dynamical cluster (1)
- dynamical transitions (1)
- frequency analysis (1)
- functional connectivity (1)
- high-frequency force (1)
- inference (1)
- interdependences (1)
- intermittency (1)
- low-frequency force (1)
- mean residence time (1)
- monsoon (1)
- mutual information (1)
- networks (1)
- noise (1)
- nonlinear dynamics (1)
- nonlinear time series analysis (1)
- pQCT (1)
- patient immobilization (1)
- period doubling (1)
- periods (1)
- phase (1)
- proteasome (1)
- protein translocation (1)
- ratchets (1)
- recognition (1)
- records (1)
- recurrence analysis (1)
- recurrence plot (1)
- series (1)
- statistical physics (1)
- stochastic process (1)
- stochastic resonance (1)
- teleconnections (1)
- time (1)
- topological community (1)
- trabecular bone (1)
- unferring cellular networks (1)
- variability (1)
- variables (1)
- vibrational resonance (1)
- Æ Recurrence Plots (1)
Institute
- Institut für Physik und Astronomie (235)
- Interdisziplinäres Zentrum für Dynamik komplexer Systeme (48)
- Institut für Geowissenschaften (23)
- Department Psychologie (17)
- Institut für Biochemie und Biologie (4)
- Department Linguistik (3)
- Extern (3)
- Institut für Informatik und Computational Science (2)
- Mathematisch-Naturwissenschaftliche Fakultät (2)
- Department Sport- und Gesundheitswissenschaften (1)
Forecasting the onset and withdrawal of the Indian summer monsoon is crucial for the life and prosperity of more than one billion inhabitants of the Indian subcontinent. However, accurate prediction of monsoon timing remains a challenge, despite numerous efforts. Here we present a method for prediction of monsoon timing based on a critical transition precursor. We identify geographic regions-tipping elements of the monsoon-and use them as observation locations for predicting onset and withdrawal dates. Unlike most predictability methods, our approach does not rely on precipitation analysis but on air temperature and relative humidity, which are well represented both in models and observations. The proposed method allows to predict onset 2 weeks earlier and withdrawal dates 1.5 months earlier than existing methods. In addition, it enables to correctly forecast monsoon duration for some anomalous years, often associated with El Nino-Southern Oscillation.
We apply the recently developed symbolic resonance analysis to electroencephalographic measurements of event- related brain potentials (ERPs) in a language processing experiment by using a three-symbol static encoding with varying thresholds for analyzing the ERP epochs, followed by a spin-flip transformation as a nonlinear filter. We compute an estimator of the signal-to-noise ratio (SNR) for the symbolic dynamics measuring the coherence of threshold-crossing events. Hence, we utilize the inherent noise of the EEG for sweeping the underlying ERP components beyond the encoding thresholds. Plotting the SNR computed within the time window of a particular ERP component (the N400) against the encoding thresholds, we find different resonance curves for the experimental conditions. The maximal differences of the SNR lead to the estimation of optimal encoding thresholds. We show that topographic brain maps of the optimal threshold voltages and of their associated coherence differences are able to dissociate the underlying physiological processes, while corresponding maps gained from the customary voltage averaging technique are unable to do so
This paper employs a complex network approach to determine the topology and evolution of the network of extreme precipitation that governs the organization of extreme rainfall before, during, and after the Indian Summer Monsoon (ISM) season. We construct networks of extreme rainfall events during the ISM (June-September), post-monsoon (October-December), and pre-monsoon (March-May) periods from satellite-derived (Tropical Rainfall Measurement Mission, TRMM) and rain-gauge interpolated (Asian Precipitation Highly Resolved Observational Data Integration Towards the Evaluation of Water Resources, APHRODITE) data sets. The structure of the networks is determined by the level of synchronization of extreme rainfall events between different grid cells throughout the Indian subcontinent. Through the analysis of various complex-network metrics, we describe typical repetitive patterns in North Pakistan (NP), the Eastern Ghats (EG), and the Tibetan Plateau (TP). These patterns appear during the pre-monsoon season, evolve during the ISM, and disappear during the post-monsoon season. These are important meteorological features that need further attention and that may be useful in ISM timing and strength prediction.
The transition from fully synchronized behavior to two-cluster dynamics is investigated for a system of N globally coupled chaotic oscillators by means of a model of two coupled logistic maps. An uneven distribution of oscillators between the two clusters causes an asymmetry to arise in the coupling of the model system. While the transverse period-doubling bifurcation remains essentially unaffected by this asymmetry, the transverse pitchfork bifurcation is turned into a saddle-node bifurcation followed by a transcritical riddling bifurcation in which a periodic orbit embedded in the synchronized chaotic state loses its transverse stability. We show that the transcritical riddling transition is always hard. For this, we study the sequence of bifurcations that the asynchronous point cycles produced in the saddle-node bifurcation undergo, and show how the manifolds of these cycles control the magnitude of asynchronous bursts. In the case where the system involves two subpopulations of oscillators with a small mismatch of the parameters, the transcritical riddling will be replaced by two subsequent saddle-node bifurcations, or the saddle cycle involved in the transverse destabilization of the synchronized chaotic state may smoothly shift away from the synchronization manifold. In this way, the transcritical riddling bifurcation is substituted by a symmetry-breaking bifurcation, which is accompanied by the destruction of a thin invariant region around the symmetrical chaotic state.