TY - BOOK A1 - Hockl, Ina A1 - Kliegl, Reinhold A1 - Kosta, Peter A1 - Staudacher, Peter A1 - Weißenborn, Jürgen ED - De Bleser, Ria ED - Burchert, Frank T1 - Linguistics in Potsdam Y1 - 1994 SN - 1616-7392 PB - Univ. Potsdam CY - Potsdam ER - TY - JOUR A1 - Soyez, Konrad A1 - Reinhold, Jürgen T1 - Biowaste treatment - recycling potential for humus reproduction JF - Chemie - Ingenieur - Technik N2 - The majority of the annually accumulated 9 million t of organics in municipal solid waste is recycled. Amongst the technological options composting is most important. 15% are treated by digestion and result in both biogas as a renewable energy source and organic residues. Compost contains considerable amounts of minerals and organic carbon which can substitute fertilizers including organic compounds. Application of compost for the reproduction of humus in soils is its most important effect. Scientifically, the applicability of the humus balancing method developed by VDLUFA is proven. It balances input and output of organic carbon during cultivation and harvest. Optimum level of humus which is a specific fixed value for each type of soils is therefore realized. An energy humus index is proposed, which may indicate preferred usage of organics as fertilizer or renewable energy source. KW - Biowaste composting KW - Humus reproduction KW - Renewable raw material KW - Soil fertility Y1 - 2012 U6 - https://doi.org/10.1002/cite.201100247 SN - 0009-286X VL - 84 IS - 7 SP - 991 EP - 998 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Flad, Heinz-Jürgen A1 - Harutyunyan, Gohar A1 - Schneider, Reinhold A1 - Schulze, Bert-Wolfgang T1 - Explicit Green operators for quantum mechanical Hamiltonians BT - I. The hydrogen atom JF - Manuscripta mathematica N2 - We study a new approach to determine the asymptotic behaviour of quantum many-particle systems near coalescence points of particles which interact via singular Coulomb potentials. This problem is of fundamental interest in electronic structure theory in order to establish accurate and efficient models for numerical simulations. Within our approach, coalescence points of particles are treated as embedded geometric singularities in the configuration space of electrons. Based on a general singular pseudo-differential calculus, we provide a recursive scheme for the calculation of the parametrix and corresponding Green operator of a nonrelativistic Hamiltonian. In our singular calculus, the Green operator encodes all the asymptotic information of the eigenfunctions. Explicit calculations and an asymptotic representation for the Green operator of the hydrogen atom and isoelectronic ions are presented. Y1 - 2011 U6 - https://doi.org/10.1007/s00229-011-0429-x SN - 0025-2611 VL - 135 IS - 3-4 SP - 497 EP - 519 PB - Springer CY - New York ER - TY - INPR A1 - Flad, Heinz-Jürgen A1 - Schneider, Reinhold A1 - Schulze, Bert-Wolfgang T1 - Asymptotic regularity of solutions of Hartree-Fock equations with coulomb potential N2 - We study the asymptotic regularity of solutions of Hartree-Fock equations for Coulomb systems. In order to deal with singular Coulomb potentials, Fock operators are discussed within the calculus of pseudo-differential operators on conical manifolds. First, the non-self-consistent-field case is considered which means that the functions that enter into the nonlinear terms are not the eigenfunctions of the Fock operator itself. We introduce asymptotic regularity conditions on the functions that build up the Fock operator which guarantee ellipticity for the local part of the Fock operator on the open stretched cone R+ × S². This proves existence of a parametrix with a corresponding smoothing remainder from which it follows, via a bootstrap argument, that the eigenfunctions of the Fock operator again satisfy asymptotic regularity conditions. Using a fixed-point approach based on Cances and Le Bris analysis of the level-shifting algorithm, we show via another bootstrap argument, that the corresponding self-consistent-field solutions of the Hartree-Fock equation have the same type of asymptotic regularity. T3 - Preprint - (2007) 05 Y1 - 2007 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-30268 ER - TY - JOUR A1 - Thiel, Marco A1 - Romano, Maria Carmen A1 - Kurths, Jürgen A1 - Rolfs, Martin A1 - Kliegl, Reinhold T1 - Twin surrogates to test for complex synchronisation N2 - We present an approach to generate (multivariate) twin surrogates (TS) based on recurrence properties. This technique generates surrogates which correspond to an independent copy of the underlying system, i.e. they induce a trajectory of the underlying system starting at different initial conditions. We show that these surrogates are well suited to test for complex synchronisation and exemplify this for the paradigmatic system of Rossler oscillators. The proposed test enables to assess the statistical relevance of a synchronisation analysis from passive experiments which are typical in natural systems Y1 - 2006 UR - http://www.mendeley.com/research/twin-surrogates-to-test-for-complex-synchronisation/#page-1 U6 - https://doi.org/10.1209/epl/i2006-10147-0 ER - TY - JOUR A1 - Baptista, Murilo da Silva A1 - Bohn, Christiane A1 - Kliegl, Reinhold A1 - Engbert, Ralf A1 - Kurths, Jürgen T1 - Reconstruction of eye movements during blinks Y1 - 2008 UR - http://chaos.aip.org/ U6 - https://doi.org/10.1063/1.2890843 SN - 1054-1500 ER - TY - INPR A1 - Engbert, Ralf A1 - Scheffczyk, Christian A1 - Krampe, Ralf-Thomas A1 - Rosenblum, Mikhael A1 - Kurths, Jürgen A1 - Kliegl, Reinhold T1 - Tempo-induced transitions in polyrhythmic hand movements N2 - We investigate the cognitive control in polyrhythmic hand movements as a model paradigm for bimanual coordination. Using a symbolic coding of the recorded time series, we demonstrate the existence of qualitative transitions induced by experimental manipulation of the tempo. A nonlinear model with delayed feedback control is proposed, which accounts for these dynamical transitions in terms of bifurcations resulting from variation of the external control parameter. Furthermore, it is shown that transitions can also be observed due to fluctuations in the timing control level. We conclude that the complexity of coordinated bimanual movements results from interactions between nonlinear control mechanisms with delayed feedback and stochastic timing components. T3 - NLD Preprints - 41 Y1 - 1997 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-14380 ER - TY - GEN A1 - Thiel, Marco A1 - Romano, Maria Carmen A1 - Kurths, Jürgen A1 - Rolfs, Martin A1 - Kliegl, Reinhold T1 - Generating Surrogates from Recurrences N2 - 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 one centre only in the brain that produces the fixational movements in both eyes or a close link between two centres. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - paper 238 KW - Æ Recurrence Plots KW - Surrogate Data KW - Hypothesis Test KW - Phase Synchronization Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-56906 ER - TY - JOUR A1 - Scheffczyk, Christian A1 - Engbert, Ralf A1 - Kurths, Jürgen A1 - Krampe, Ralf-Thomas A1 - Kliegl, Reinhold T1 - Nonlinear Phenomena in Polyrhythmic Hand Movements N2 - In this paper we apply symbolic transformations as a visualisation technique for analysing rhythm production. It is shown that qualitative information can be extracted from the experimental data. This approach may provide new insights into the organisation of temporal order by the brain on different levels of description. A simple phenomenological model for the explanation of the observed phenomena is proposed. Y1 - 1995 SN - 981-02-2689-6 ER - TY - JOUR A1 - Thiel, Marco A1 - Romano, Maria Carmen A1 - Kurths, Jürgen A1 - Rolfs, Martin A1 - Kliegl, Reinhold T1 - Generating surrogates from recurrences N2 - 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. Y1 - 2008 UR - http://rsta.royalsocietypublishing.org/ SN - 1364-503X ER -