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Report from NA49
No full textabstractEN: The signatures of the onset of deconfinement, found by the NA49 experiment at low SPS energies, are confronted with new results from the Beam Energy Scan (BES) program at BNL RHIC and CERN LHC results. Additionally, new NA49 results on chemical (particle ratio) fluctuations, azimuthal angle fluctuations, intermittency of di-pions, etc. are presented.score:
Limits of time-delayed feedback control
No full textabstractEN: General features of stability domains for time-delayed feedback control exist, which can be predicted analytically. We clarify, why the control scheme with a single delay term can only stabilise orbits with short periods or small Lyapunov exponents, and derive a quantitative estimate. The limitation can be relaxed by employing multiple delay terms. In particular, the extended time delay autosynchronisation method is investigated in detail. Analytic calculations are in good agreement with results of numerical simulations and with experimental data from a nonlinear diode resonator.score: 35collation: 158-16
Phase transitions in social networks
No full textabstractEN: We study a model of network with clustering and desired node degree. The original purpose of the model was to describe optimal structures of scientific collaboration in the European Union. The model belongs to the family of exponential random graphs. We show by numerical simulations and analytical considerations how a very simple Hamiltonian can lead to surprisingly complicated and eventful phase diagram.score: 0collation: 133-13
A Photonic Crystal Fiber and Fiber Bragg Grating-Based Hybrid Fiber-Optic Sensor System
No full textabstractEN: A hybrid sensor that operates in the intensity domain by converting the polarization and wavelength information from the photonic crystal fiber sensor and fiber Bragg grating (FBG) sensor, respectively, into intensity variation is presented in this paper. The hybrid fiber-optic sensor system involves a combination of a polarimetric sensor based on a photonic crystal fiber and a FBG sensor and is used for simultaneous strain and temperature measurement. The strain sensitivity of the polarization maintaining photonic crystal fiber at different lengths and the corresponding slope required for the edge filter which converts the FBG wavelength information into intensity are studied and presented in this paper. The proposed sensor configuration has a wide range of applications in smart fiber-optic sensing.score: 30collation: 39-4
Tunable highly birefringent solid-core photonic liquid crystal fibers
No full textabstractEN: Experimental results of temperature-, electric field-, and hydrostatic-pressure-induced effects in solid-core highly birefringent photonic liquid crystal fibers are presented. Selective infiltration of the photonic crystal fibers with liquid crystals was found to induce birefringence axes switching resulting in a variety of tunable photonic liquid crystal fibers-based devices.score: 20collation: 1021-103
Nonlinear liquid crystalline directional coupler
No full textabstractEN: A polished fiber half coupler with a nematic liquid crystal as a multimode planar waveguide overlay has been investigated. Experimental results show an existence of optical bistability with contrast approximately 40 percent for laser power approximately 340mW at (lambda) equals 514 nm. Observation of the optical bistability is explained as a result of an optically induced reorientational effect in a liquid crystalline layer.score: 3collation: 406-40
Magnetic mineralogy and paleomagnetism of serpentinized ultramafic rocks from the Braszowice-Brzeźnica fragment of sudetic paleozoic ophiolite
No full textabstractEN: Complex paleomagnetic, rock-magnetic and mineralogical studies were performed on serpentinized utramafic rocks from Braszowice-Brzeźnica massif (BB) situated at the southern extremity of the Niemcza Shear Zone, close to the Sudetic Marginal Fault. Studies of magnetic minerals revealed presence of several varieties of magnetite grains, and partly altered Cr-spinels. Paleomagnetic studies revealed stable component HS of natural remanence carried by magnetite formed probably during the initial serpentinization. The directions of HS have good grouping within each locality, but differ between localities. Studies of anisotropy of magnetic susceptibility (AMS) have shown that directions of anisotropy axes are steep instead of horizontal as is common within the Niemcza Shear Zone. Taking advantage of the directions of AMS we rotated the directions of HS and brought them to the reference direction for the Sudetes for 372 Ma. We suggest that after acquiring AMS and HS during the Upper Devonian, the BB became divided into multiple units due to tectonic activity in the region.score: 0collation: 269-29
Nonstationary Pomeau-Manneville intermittency in systems with a periodic parameter change
No full textabstractEN: Pomeau-Manneville intermittency in nonstationary systems is investigated. If one of the parameters characterizing a dynamical system is changed periodically, periodic orbits may appear even when the value of this parameter remains in a range which, in the stationary case, yields chaotic behavior. This property may be used for the control of systems exhibiting intermittency. If the parameter change is not large enough, a periodic orbit does not appear but the distribution of the laminar phases is modified. In the case of type I intermittency, this means a broadening of such a distribution or, alternatively, a splitting of its right peak. We present a theory of these phenomena. Numerical simulations both for one-dimensional maps and for flows support our predictions. Some of the phenomena discussed here were observed earlier in time series of heart rate variability.score: 35collation: 1-1
Verification of implantable cardioverter defibrillator (ICD) interventions by nonlinear analysis of heart rate variability – preliminary results
No full textabstractEN: Aims Conventional ICD algorithms yield approximately 10–30\% of spurious interventions. Our aim was to check whether nonlinear dynamics methods might be useful in the verification of ICD interventions. Methods and results We extracted 190 consecutive RR files (approximately 2000–9000 RR intervals long) from the ICDs of 70 patients (36 with coronary artery disease, 8 with hypertrophic cardiomyopathy, 19 with dilated cardiomyopathy and 7 with other diseases). The 3D phase space trajectories in delay coordinates, window pattern entropy, and algorithmic complexity of the RR intervals were examined within a 50 beat sliding window. Data were not filtered for arrhythmia and artefacts. Of the 83 recordings with appropriate interventions 79 were correctly recognised in a blind test. Two interventions were not identified in patients with fast atrial fibrillation and two in cases of complex and frequent forms of arrhythmia. There were nine spurious interventions. In all except one case (atrial fibrillation with a fast ventricular response) the analysis by nonlinear methods showed that the intervention was not necessary. All of the 98 control recordings were correctly identified in the blind test. Conclusions The results show that nonlinear dynamics methods may be used to supplement the existing ICD detection algorithms to enhance the detection success rate.score: 0collation: 617-62
Detection of the type of intermittency using characteristic patterns in recurrence plots
No full textabstractEN: One of the common routes to chaos is intermittency. Identification of the intermittency type is usually made using the properties of the probability distribution of laminar phases and of the average length of the laminar phases. Both have a statistical character and to obtain them a long time series has to be examined. Here, we present a recurrence plot method applicable to the analysis of short time series and through which the type of intermittency may be identified. The three types of intermittency introduced by Pomeau and Manneville and a chaos-chaos intermittency induced by interior crisis were examined. The identification of the type of intermittency is equivalent to the identification of the bifurcation associated with it. Our result seems particularly interesting as our method allows the analysis of short time series. The effect of the measurement noise on the effectiveness of the method is also discussed. An application of the method to the detection of type I intermittency in measured heart rate variability data is discussed.score: 35collation: 02621