Workshop Dynamical Systems and Applications in the framework of the project FP7-PEOPLE-2012-IRSES-316338 within the 7th European Community Framework Programme Hotel PIRAMIDA, Maribor, Slovenia 23 August 2013 - 24 August 2013 Book of Abstracts Workshop Dynamical Systems and Applications in the framework of the project FP7-PEOPLE-2012-IRSES-316338 within the 7th European Community Framework Programme Hotel PIRAMIDA, Maribor, Slovenia 23 August 2013 - 24 August 2013 Organizer C ENTER FOR A PPLIED M ATHEMATICS AND T HEORETICAL P HYSICS U NIVERZA V M ARIBORU • U NIVERSITY OF M ARIBOR K REKOVA 2 • SI-2000 M ARIBOR • S LOVENIA Phone +(386) (2) 2355 350 and 2355 351 • Fax +(386) (2) 2355 360 www.camtp.uni-mb.si Co-organizer FACULTY OF N ATURAL S CIENCES AND M ATHEMATICS U NIVERSITY OF M ARIBOR , K ORO Sˇ KA CESTA 160, SI-2000 M ARIBOR , S LOVENIA Phone +(386) (2) 2293 844 • Fax +(386) (2) 2518 180 www.fnm.uni-mb.si Sponsor Slovenian Research Agency CIP - Kataloˇzni zapis o publikaciji Univerzitetna knjiˇznica Maribor 001.891:061.1EU:517.93(082)(048.3) WORKSHOP dynamical systems and applications in the framework of the project FP7-PEOPLE-2012-IRSES-316338 within the 7th European Community Framework Programme, 23 August - 24 August 2013 : book of abstracts / [urednik Valery Romanovski ; organizer Center for applied mathematics and theoretical physics]. - Maribor : Center za uporabno matematiko in teoretiˇcno fiziko, 2013 ISBN 978-961-281-121-1 1. Center for applied mathematics and theoretical physics (Maribor) COBISS.SI-ID 75254273 1 Organizing Committee Prof. Dr. Marko Robnik CAMTP, University of Maribor, Slovenia Prof. Dr. Valery Romanovski CAMTP, University of Maribor, Slovenia Prof. Dr. Yonghui Xia Zhejiang Normal University, China 2 Invited Speakers Prof. Dr. Vladimir Amel’kin, Belarusian State University, Belarus Prof. Dr. Ilknur Kusbeyzi Aybar, Yeditepe University, Turkey Mr. Orhan Ozgur Aybar, Yeditepe University, Turkey Prof. Dr. Xingwu Chen, Sichuan University, China Prof. Dr. Wei Ding, Shanghai Normal University, China Prof. Dr. Maoan Han, Shanghai Normal University, China Dr. Athanasios Manos, CAMTP, University of Maribor and University of Nova Gorica, Slovenia Prof. Dr. Matej Mencinger, University of Maribor, Slovenia Prof. Dr. Alexander Prokopenya, Warsaw University of Life Sciences, Poland Prof. Dr. Marko Robnik, CAMTP, University of Maribor, Slovenia Prof. Dr. Valery Romanovski, CAMTP, University of Maribor, Slovenia Prof. Dr. Andreas Ruffing, Technical University of Munchen, Germany Prof. Dr. Ekaterina Vasil’eva, Saint Petersburg State University, Russia Prof. Dr. Andreas Weber, University of Bonn, Germany Prof. Dr. Yepeng Xing, Shanghai Normal University, China Prof. Dr. Weinian Zhang, Sichuan University, China ˇ Prof. Dr. Vesna Zupanovi´ c, University of Zagreb, Croatia 3 SCHEDULE Friday 23 August 9:30-9:40 Opening Chairman Weinian Zhang 09:40-10:20 Maoan Han 10:20-11:00 Andreas Weber 11:00-11:30 Tea & Coffee 11:30-12:10 Ekaterina Vasileva 12:10-12:50 Athanasios Manos 12:50-13:30 Wei Ding 13:30-15:00 Lunch Chairman Andreas Weber 15:00-15:40 Vladimir Amel’kin 15:40-16:20 Xingwu Chen 16:20-16:50 Tea & Coffee 16:50-17:30 Andreas Ruffing 17:30-18:10 Ilknur Kusbeyzi Aybar 18:10-18:30 Lingling Liu 19:00 Welcome Dinner 4 Saturday 24 August Chairman Maoan Han 09:00-09:40 Marko Robnik 09:40-10:20 Weinian Zhang 10:20-11:10 Tea & Coffee 11:10-11:50 Alexander Prokopenya 11:50-12:30 Yepeng Xing ˇ 12:30-13:10 Vesna Zupanovi´ c 13:10-15:00 Lunch Chairman Alexander Prokopenya 15:00-15:40 Valery Romanovski 15:40-16:20 Matej Mencinger 16:20-16:50 Tea & Cofee 16:50-17:30 Orhan Ozgur Aybar 17:30-17:50 Yuanyuan Liu 17:50-18:10 Maˇsa Dukari´c 18:30 Dinner 5 ABSTRACTS 6 Strongly isochronous two-dimensional holomorphic systems of the ordinary differential equations VLADIMIR V. AMEL’KIN Belarusian State University Minsk, Nezavisimosti avenue 4 220030 Minsk, Republic of Belarus [email protected] http://www.bsu.by We consider the real autonomous holomorphic systems on the plane with pure imaginary roots of the characteristic equation of the first approximation system. We give an overview of practically all known results concerning the strong isochronicity of polynomial centers with the indication of the maximum order of strong isochronicity and the initial polar angle. In particular, quadratic systems, systems with incomplete polynomials of the third, fourth, fifth degrees are considered. 7 Stability, bifurcation and normal form analysis of predator-prey systems ILKNUR KUSBEYZI AYBAR Yeditepe University 34755 Istanbul, Turkey [email protected] http://www.yeditepe.edu.tr The predator-prey system attempts to model the relationship in the populations of different species that share the same environment where some of the species (predators) prey on the others. The wellknown problem the Lotka-Volterra model which stands as a starting point for more complex generalizations of predator-prey system lacks to represent realistic models with its unrealistic stability characteristics. Therefore generalizations including higher nonlinear interactions are studied. Changes in the number and stability of equilibrium points in the generalized predator-prey system that lead to qualitative changes in the behavior of the system as a function of some of its parameters are studied by bifurcation analysis. Numerical methods and the approach provided by approximate techniques near equilibrium points are used in the analysis. References [1] I. Kusbeyzi, O.O. Aybar, A. Hacinliyan, Stability and bifurcation in two species predator-prey models, Nonlinear Analysis: Real World Applications 12 (2011) 377-387. [2] I. Kusbeyzi, A. Hacinliyan, Bifurcation scenarios of some modified predator-prey nonlinear systems, Journal of Applied Functional Analysis 4(3) (2009) 519-527. 8 [3] Y. Nutku, Hamiltonian structure of the Lotka-Volterra equations, Physics Letters A I145 (1990) 27-28. 9 Regular or chaotic behavior in a class of hamiltonian systems ORHAN OZGUR AYBAR Gebze Institute of Technology Department of Mathematics, Gebze-Kocaeli, Turkey Yeditepe University Department of Information Systems and Technologies, Istanbul, Turkey [email protected] In this paper we study possible regular and chaotic behavior and approximately conserved quantities in a class of generalized H´enonHeiles and classical Yang-Mills Hamiltonians. We present a method for identifying chaotic and regular behavior by considering the evolution of its tangent space. The method is applied to a class of Hamiltonian systems to demonstrate the idea. In order to distinguish a small positive characteristic exponent from a zero characteristic exponent, a method for identifying the presence of zero characteristic exponents is suggested. Approximately conserved quantities are investigated via Poisson brackets of the Hamiltonian and possible invariants. This work is based on my PhD Thesis supervised by Prof. A. Hacinliyan. References [1] O. Ozgur Aybar, I. Birol, A. Hacinliyan, I. Kusbeyzi Aybar, Regular or Chaotic Behavior in a Class of Hamiltonian Systems, in preparation 10 Local bifurcation of critical periods for isochronous centers XINGWU CHEN Department of Mathematics, Sichuan University Chengdu, Sichuan 610064, P. R. China [email protected] In this talk we discuss the local bifurcation of critical periods for planar differential systems. From 1989 when Chicone and Jacobs founded the basic theory of the critical period bifurcation, many works have been done for several families of systems, specially for polynomial systems. Here we introduce some interesting results and mainly discuss the case that critical periods bifurcating from isochronous centers. For the isochronous centers of an n-th degree homogeneous vector field perturbing in m-th degree time-reversible systems, period-bifurcation functions are presented as integrals of analytic functions which depend on perturbation coefficients and the problem of critical periods is reduced to finding zeros of a judging function. References [1] C. Chicone, M. Jacobs, Bifurcation of critical periods for plane vector fields, Trans. Amer. Math. Soc. 312(1989) 433-486. [2] X. Chen, V. G. Romanovski, W. Zhang, Critical periods of perturbations of reversible rigidly isochronous centers, J. Differential Equations 251(2011) 1505-1525. 11 Traveling wave solutions for some reaction-diffusion models WEI DING Department of Applied Mathematics Shanghai Normal University Shanghai, China, 200234 [email protected] http://www.shnu.edu.cn We study the traveling wave solutions of two kinds of reactiondiffusion models. We discuss the existence of traveling wave solutions with the techniques of qualitative analysis, upper-lower solutions, and monotone iteration method. We also find the precise value of the minimum speeds that are significant to study the spreading speed. References [1] L.J.S. Allen, B.M. Boller, Y. Lou and A.L. Nevai, Asymptotic profiles of the steady states for an SIS epidemic reactiondiffusion model, Discrete Contin. Dyn. Syst. A, 21(2008), 1-20. [2] J. Yang, S. Liang and Y. Zhang, Travelling Waves of a Delayed SIR Epidemic Model with Nonlinear Incidence Rate and Spatial Diffusion. PLoS ONE 6(6): e21128. doi:10.1371/journal.pone.0021128 (2011). [3] W.Huang, Problem on Minimum Wave Speed foe a LotkaVolterra Reaction- Diffusion Competition Model. J Dyn Diff Equat. 22(2010),285-297. 12 [4] W.Huang, W.Wu, Minimum wave speed for a diffusive competition model with time delay. Journal of Applied Analysis and Computation. 1(2)(2011),205-218. [5] R. Peng and S. Liu, Global stability of the steady states of an SIS epidemic reaction-diffusion model, Non. Analysis, 71(2009), 239-247. 13 The solution of the 1 : -3 resonant center problem in the quadratic case ˇ DUKARIC, ´ BRIGITA FERCEC ˇ MASA CAMTP - Center for Applied Mathematics and Theoretical Physics University of Maribor, Krekova 2 SI-2000 Maribor, Slovenia [email protected]; [email protected] JAUME GINE´ Departamento de Matematica Universitat de Lleida, Avda. Jaume II, 69 25001 Lleida, Spain [email protected] The 1 : −3 resonant center problem in the quadratic case is to find necessary and sufficient conditions for existence of local analytic first integrals of the differential system x˙ = x − a10 x2 − a01 xy − a12 y 2 , y˙ = −3y + b21 x2 + b10 xy + b01 y 2 . Dividing this problem into two smaller problems, where a01 = 0 and a01 = 1, we gain 25 center cases for a01 = 1 and 11 cases for a01 = 0. The necessary conditions are obtained using modular arithmetics. The main tool to prove the sufficiency of the obtained conditions is the method of Darboux, however some other technics were used as well. 14 References [1] X. Chen, J. Gine, V.G. Romanovski, D.S. Shafer, The 1 : −q resonant center problem for certain cubic Lotka-Volterra systems, Appl. Math. Comput. 218 (2012), 11620–11633. [2] V.G. Romanovski, M. Preˇsern, An approach to solving systems of polynomials via modular arithmetics with applications, J. Comput. Appl. Math. 236 (2011), no. 2, 196–208. [3] M. Dukari´c, B. Ferˇcec, J. Gin´e, The solution of the 1:-3 resonant center problem in the quadratic case, submitted to J. Comput. Appl. Math. (2013). 15 The stability of some kinds of generalized homoclinic loops in planar piecewise smooth systems FENG LIANG, MAOAN HAN† Department of Mathematical, Shanghai Normal University Shanghai, China, 200234 † [email protected] In this paper we present some kinds of generalized homoclinic loops in planar piecewise smooth systems. By establishing Poincar´ e map, we study the stability of these homoclinic loops. For each case, a criteria for stability is given. As applications, several concrete piecewise systems are considered. References [1] A. F. Filippov, Differential Equations with Discontinuous Righthand Sides. Kluwer Academic Netherlands (1988) . [2] M. Han, Asymptotic expansions of Melnikov function and limit cycle bifurcations. International Journal of Bifurcation and Chaos 12 (2012) 1-20 [3] M. Han, Bifurcation theory of limit cycles. Science Press Beijing (2013) . [4] M. Han and W. Zhang, On the Hopf bifurcation in nonsmooth planar systems. Journal of Differential Equations 248 (2010) 2399416. [5] M. Kunze, Non-Smooth Dynamical Systems. Springer-Verlag Berlin (2000). [6] F. Liang, M. Han and V. G. Romanovski, Bifurcation of limit cycles by perturbing a piecewise linear Hamiltonian system with a homoclinic loop. Nonlinear Analysis: Theory, Methods & Applications 75 (2012) 4355-4374. 16 [7] F. Liang and M. Han, Limit cycles near generalized homoclinic and double homoclinic loops in piecewise smooth systems. Chaos, Solitons & Fractals 45 (2012) 454-464. [8] J. Yang, M. Han and W. Huang, On Hopf bifurcations of piecewise planar Hamiltonian systems. Journal of Differential Equations 250 (2011) 1026-1051. 17 Identification of focus and center in a 3-dim system LINGLING LIU Department of Mathematics, Sichuan University Chengdu, Sichuan 610064, P.R.China [email protected] We identify focus and center for a generalized Lorenz system, a 3dimensional quadratic polynomial differential system. It is a wellknown routine to restrict the system to its a center manifold, but the approximation of the center manifold brings a great complexity in the computation of Lyapunov quantities and their dependence even if the original system is not of high degree. On the other hand, in order to determine if an center-focus equilibrium is a center, those criteria for planar systems such as time-reversibility and integrability are not available on an approximated center manifold. We prove its Darboux integrability by finding an invariant surface, showing that the equilibrium of center-focus type is actually a rough center on a center manifold. References [1] Lingling Liu, Bo Gao, Dongmei Xiao, Weinian Zhang, Identification of Focus and Center in a 3-Dimensional System, submitted to Discr. Contin. Dyn. Syst. B (2013) 18 Limit cycle bifurcations of a class of piecewise smooth Li´enard systems YUANYUAN LIU, MAOAN HAN Department of Mathematical, Shanghai Normal University Shanghai, China, 200234 [email protected]; [email protected] VALERY ROMANOVSKI Center for Applied Mathematics and Theoretical Physics University of Maribor Krekova 2, Maribor 2000, Slovenia [email protected] In this paper, we consider a class of piecewise smooth Li´enard systems as follows x˙ = y, y˙ = −g(x) − f (x)y, where g(x) and f (x) are piecewise polynomials. We classify the unperturbed system into three types and study the bifurcation of limit cycles for the above system. By studying the expansions of the first order Melnikov function, we give some new results on the number of limit cycles in Hopf and homoclinic bifurcations. References [1] M. Han, Bifurcation theory of limit cycles. Science Press Beijing (2013) . [2] M. Han, Asymptotic expansions of Melnikov function and limit cycle bifurcations. International Journal of Bifurcation and Chaos 12 (2012) 1-20 19 [3] M. Han and W. Zhang, On the Hopf bifurcation in nonsmooth planar systems. Journal of Differential Equations 248 (2010) 2399416. [4] X. Liu and M. Han, Bifurcation of limit cycles by perturbing piecewise Hamiltionian systems, International Journal of Bifurcation and Chaos in Applied Sciences and Engineering 5 (2010) 1-12. [5] L. Wei, F. Liang and S. Lu, Limit cycle bifurcations near a generalized homoclinic loop in piecewise smooth systems with a hyperbolic saddle on a switch line , submitted to Applied Mathematics and Computation. (2013) [6] F. Liang, M. Han and V. G. Romanovski, Bifurcation of limit cycles by perturbing a piecewise linear Hamiltonian system with a homoclinic loop. Nonlinear Analysis: Theory, Methods & Applications 75 (2012) 4355-4374. [7] F. Liang and M. Han, Limit cycles near generalized homoclinic and double homoclinic loops in piecewise smooth systems. Chaos, Solitons & Fractals 45 (2012) 454-464. [8] J. Yang, M. Han and W. Huang, On Hopf bifurcations of piecewise planar Hamiltonian systems. Journal of Differential Equations 250 (2011) 1026-1051. 20 Dynamical localization, spectral statistics and localization measure in the kicked rotator THANOS MANOS1,2 , MARKO ROBNIK1 1 CAMTP - Center for Applied Mathematics and Theoretical Physics University of Maribor, Krekova 2, SI-2000 Maribor, Slovenia and 2 School of applied sciences University of Nova Gorica, Vipavska 11c, SI-5270, Ajdovˇscˇ ina, Slovenia [email protected] • www.camtp.uni-mb.si/camtp/manos We study the kicked rotator in the classically fully chaotic regime using Izrailev’s N -dimensional model for various N ≤ 4000, which in the limit N → ∞ tends to the quantized kicked rotator. We do not treat only the case K = 5 as studied previously, but many different values of the classical kick parameter 5 ≤ K ≤ 35, and also many different values of the quantum parameter k ∈ [5, 60]. We describe the features of dynamical localization of chaotic eigenstates as a paradigm for other both time-periodic and time-independent (autonomous) fully chaotic or/and mixed type Hamilton systems. We generalize the scaling variable Λ = l∞ /N to the case of anomalous diffusion in the classical phase space, by deriving the localization length l∞ for the case of generalized classical diffusion. We greatly improve the accuracy and statistical significance of the numerical calculations, giving rise to the following conclusions: (C1) The level spacing distribution of the eigenphases (or quasienergies) is very well described by the Brody distribution, systematically better than by other proposed models, for various Brody exponents βBR . (C2) We study the eigenfunctions of the Floquet operator and characterize their localization properties using the information entropy measure, which after normalization is given by βloc in the interval [0, 1]. The level repulsion parameters βBR and βloc are almost linearly related, close to the identity line. (C3) We show the existence of a 21 scaling law between βloc and the relative localization length Λ, now including the regimes of anomalous diffusion. The above findings are important also for chaotic eigenstates in time-independent systems (Batisti´c and Robnik 2010,2013), where the Brody distribution is c onfirmed to a very high degree of precision for dynamically localized chaotic eigenstates even in the mixed-type systems (after separation of regular and chaotic eigenstates). References [1] [2] [3] [4] [5] [6] Izrailev F M 1988 Phys. Lett. A 134 13 Izrailev F M 1990 Phys. Rep. 196 299 Batisti´c B and Robnik M 2010 J. Phys. A: Math. Gen. 43 Manos T and Robnik M 2013 Phys. Rev. E 87 062905 Batisti´c B, Manos T and Robnik M 2013 EPL 102 50008 Batisti´c B and Robnik M 2013 J. Phys. A (in press) 22 The study of isochronicity and critical period bifurcations on center manifolds of some 3-dim polynomial systems MATEJ MENCINGER FG - Faculty of Civil Engineering University of Maribor, Slomˇskov trg 15 SI-2000 Maribor, Slovenia [email protected] http://www.fg.uni-mb.si/ and IMFM - Institute of Mathematics, Physics and Mechanics SI-1000 Ljubljana, Slovenia The main topic of this talk is the investigation of a quadratic 3D system of ODEs u˙ = −v + au2 + av 2 + cuw + dvw v˙ = u + bu2 + bv 2 + euw + f vw w˙ = −w + Su2 + Sv 2 + T uw + U vw (1) with real coefficients a, b, c, d, e, f, S, T and U . System (1) was studied already in [1], and further in [2,3], where planar polynomial systems of ODEs appearing on the center manifold of (1) were studied. Using the solutions of the center-focus problem from [1], confirmed in [3] by the so called modular approach [4], we present the investigation of four (at most three parameter-) families of (at most third degree) polynomial systems corresponding to the center varieties of (1). Thus, all systems under consideration correspond to a center manifold filled with closed trajectories (corresponding to periodic solutions of (1)). 23 In particular, in the talk I shall present the criteria on the coefficients of the system to distinguish between the cases of isochronous and non-isochronous oscillations, considered in [2,3]. Bifurcations of critical periods of the system will be presented as well. References [1] V. F. Edneral, A. Mahdi, V. G. Romanovski and D. S. Shafer, The center problem on a center manifold in R3 , Nonlinear Anal. 75 (2012) 2614-2622. [2] B. Ferˇcec, M. Mencinger , Isochronicity of centers at a center manifold. AIP conference proceedings, 1468. Melville, N.Y.: American Institute of Physics, 2012, pp. 148-157. [3] V. G. Romanovski, M. Mencinger and, B. Ferˇcec, Investigation of center manifolds of 3-dim systems using computer algebra, Program. Comput. Softw. 39 (2013) 67-73. [4] V. G. Romanovski, M. Preˇsern, An approach to solving systems of polynomials via modular arithmetic with applications. Journal of Computational and Applied Mathematics 236 (2011) 196-208. 24 Adiabatic invariants and some statistical properties of the time-dependent linear and nonlinear oscillators MARKO ROBNIK CAMTP - Center for Applied Mathematics and Theoretical Physics University of Maribor, Krekova 2 SI-2000 Maribor, Slovenia [email protected] http://www.camtp.uni-mb.si We consider 1D time dependent Hamiltonian systems and their statistical properties, namely the time evolution of microcanonical distributions, whose properties are very closely related to the existence and preservation of the adiabatic invariants. We review the elements of the recent developments by Robnik and Romanovski (2006-2008) for the entirely general 1D time dependent linear oscillator and try to generalize the results to the 1D nonlinear Hamilton oscillators, in particular the power-law potentials like e.g. quartic oscillator. Furthermore we consider the limit opposite to the adiabatic limit, namely parametrically kicked 1D Hamiltonian systems. Even for the linear oscillator interesting properties are revealed: an initial kick disperses the microcanonical distribution to a spread one, but an anti-kick at an appropriate moment of time can annihilate it, kicking it back to the microcanonical distribution. The case of periodic parametric kicking is also interesting. Finally we propose that in the parametric kicking of a general 1D Hamilton system the average value of the adiabatic invariant always increases, which we prove for the power-law potentials. We find that the approximation of kicking is good for quite long times of the parameter variation, up to the order of not much less than one period of the oscillator. We also look at the behaviour of the quartic oscillator for the case of the kick and anti-kick, and also the periodic kicking. 25 References [1] G. Papamikos, M. Robnik, J.Phys.A: Math.Theor. 315102. 44 (2011) [2] M. Robnik, V.G. Romanovski, J.Phys.A: Math.Gen. L35-L41. 39 (2006) [3] M. Robnik, V.G. Romanovski, Open Sys. and Inf. Dynamics 13 (2006) 197-222. [4] M. Robnik, V.G. Romanovski, J.Phys.A:Math.Gen. 39 (2006) L551-L554. H.-J. ¨ Stockmann, [5] A.V. Kuzmin, M. Robnik, Rep. Math. Phys. 60 (2007) 69-84. [6] M. Robnik, V.G. Romanovski, ”Let’s Face Chaos through Nonlinear Dynamics”, Proceedings of the 7th International summer school/conference, Maribor-Slovenia, 2008, in AIP Conf. Proc. 1076, Eds. M.Robnik and V.G. Romanovski. [7] M. Robnik, V.G. Romanovski, J.Phys.A: Math. Theor. 5093. 33 (2000) [8] G. Papamikos, B.C. Sowden, M. Robnik, Nonl.Phen.Compl.Sys. 15, No 3, (2012) 227-240. 26 Integrability of polynomial systems of ODEs VALERY G. ROMANOVSKI CAMTP - Center for Applied Mathematics and Theoretical Physics University of Maribor, Krekova 2 SI-2000 Maribor, Slovenia [email protected] http://www.camtp.uni-mb.si Consider polynomial vector fields on Rn having a singularity at the origin with non-degenerate linear part. We discuss the problems of existence of analytic first integrals, center manifolds, periodic solutions and the problem of stability, and their interconnection. We also explicitly compute center manifolds and first integrals for several families of systems with quadratic and cubic higher order terms and describe computational methods for the study. We also discuss main mechanisms for integrability: Darboux integrability and timereversibility. Bifurcations of periodic solutions for some families of polynomial systems are considered as well. References [1] A. Mahdi, V. G. Romanovski, D. S. Shafer, Stability and periodic oscillations in the Moon-Rand systems, Nonlinear Analysis: Real World Applications 14 (2012) 294-313. [2] V. G. Romanovski, M. Preˇsern, An approach to solving systems of polynomials via modular arithmetic with applications. Journal of Computational and Applied Mathematics 236 (2011) 196-208. 27 [3] Z. Hu, M. Aldazharova, T. M. Aldibekov, V. G. Romanovski, Integrability of 3-dim polynomial systems with three invariant planes, submitted to Nonlinear Dynamics (2013) [4] Z. Hu, H. Maoan, V. G. Romanovski, Local integrability of a family of three-dimensional quadratic systems, submitted to Physica D (2013) 28 Quantum difference–differential equations ANDREAS L. RUFFING Technische Universit¨at Munchen ¨ Department of Mathematics Boltzmannstraße 3 D-85747 Garching, Germany [email protected] http://www-m6.ma.tum.de/∼ruffing/ Differential equations which contain the parameter of a scaling process are usually referred to by the name Quantum Difference–Differential Equations. Some of their applications to discrete models of the ¨ Schrodinger equation are presented and some of their rich, filigrane und sometimes unexpected analytic structures are revealed. A Lie-algebraic concept for obtaining basic adaptive discretizations is explored, generalizing the concept of deformed Heisenberg algebras by Julius Wess. They are also related to algebraic foundations of quantum groups in the spirit of Ludwig Pittner. Some of the moment problems of the underlying basic difference ¨ equations are investigated. Applications to discrete Schrodinger theory are worked out and some spectral properties of the aris¨ ing operators are presented, also in the case of Schrodinger operators with basic shift–potentials and in the case of ground state difference–differential operators. For the arising orthogonal function systems, the concept of inherited orthogonality is explained. The results in this talk are mainly related to a recent joint work with Sophia Roßkopf and Lucia Birk. 29 References ¨ ¨ [1] A. Ruffing: Habilitationsschrift TU Munchen, Fakult¨at fur Mathematik: Contributions to Discrete Schr¨odinger Theory (2006). [2] M. Meiler, A. Ruffing: Constructing Similarity Solutions to Discrete Basic Diffusion Equations, Advances in Dynamical Systems and Applications, Vol. 3, Nr. 1, (2008) 41–51. [3] A. Ruffing, M. Simon: Difference Equations in Context of a qFourier Transform, New Progress in Difference Equations, CRC press (2004), 523–530. [4] A. Ruffing, M. Simon: Analytic Aspects of q-Delayed Exponentials: Minimal Growth, Negative Zeros and Basis Ghost States, Journal of Difference Equations and Applications, Vol. 14, Nr. 4 (2008), 347–366. [5] L. Birk, S. Roßkopf, A. Ruffing: New Potentials in Discrete Schr¨odinger Theory, American Institute of Physics Conference Proceedings 1468, 47 (2012). [6] L. Birk, S. Roßkopf, A. Ruffing: Difference-Differential Operators for Basic Adaptive Discretizations and Their Central Function Systems, Advances in Difference Equations (2012), 2012 : 151. 30 Stable periodic points of n-dimentional diffeomorphisms EKATERINA V. VASILEVA St. Petersburg State University Universitetski pr. 28, St. Petersburg, Russia [email protected] We consider a self-diffeomorphism of (n+m)-space with a fixed hyperbolic point at the origin. The existence of nontransversal homoclinic point is assumed; i.e., intersection of the stable and unstable manifolds contains a point, referred to as a homoclinic point, and this point is a point of tangency of these manifolds. It follows from results of Sh. Newhouse, B.F. Ivanov, L.P.Shilnikov, S. V. Gonchenko and other authors that, when the stable and unstable manifolds are tangent in a certain way, a neighborhood of the homoclinic point may contain stable periodic points, but at least one of the characteristic exponents for such points tends to zero with increasing the period. The goal of the talk is to show that under certain conditions imposed mainly on the character of tangency of the stable and unstable manifolds, a neighborhood of the homoclinic point contains an infinite set of stable periodic points whose characteristic exponents are negative and bounded away from zero. An example of such a diffeomorphism was considered in the monograph of V.A. Pliss. 31 References [1] Newhouse Sh., Diffeomorphisms with finitely many sinks, Topology v.12 p. 9-12 (1974). [2] Ivanov B.F., Stability of Trajectories That Do Not Leave a Neighborhood of a Homoclinic Curve , Differ. Uravn., 1979, v. 15, no.8, pp. 1411-1419. [3] Gonchenko S.V., Turaev D. V., Shilnikov L.P., Dynamical Phenomena in Multidimensinal Systems with a Structurally Unstable Poincare Curve, Dokl. RAN, 1993, v. 330, no. 2, pp. 144-147. [4] Pliss V. A. Integralnye mnozhestva perodicheskikh system differentsialnykh uravnenii (Integral Sets of Periodic Systems of Differential Equations), Moscow; Nauka, 1977. [5] Vasileva E.V. Multidimensional Diffeomorphisms with Stable Periodic Points, Dokl. RAN, 2011, v. 441, no. 3, pp. 299-301. [6] Vasileva E.V. Diffeomorphisms of the Plane with Stable Perodic Points, Differ. Uravn., 2012, v. 48, no.3, pp. 307-315. 32 Efficient symbolic method to detect Hopf bifurcations in chemical reaction networks ANDREAS WEBER1 , HASSAN ERRAMI1 , MARKUS EISWIRTH1 ,DIMA GRIGORIEV2 , WERNER M. SEILER3 , THOMAS STURM4 1 Institut fur ¨ Informatik II, Universit¨at Bonn Friedrich-Ebert-Allee 144, 53113 Bonn, Germany [email protected] 2 CNRS, Math´ematiques, Universit´e de Lille Villeneuve d’Ascq, 59655, France 3 Institut fur ¨ Mathematik, Universit¨at Kassel Heinrich-Plett-Strasse 40 34132 Kassel, Germany 4 Max-Planck-Institut fur ¨ Informatik , RG 1: Automation of Logic 66123 Saarbrucken, ¨ Germany Determining potential oscillatory behavior of (bio-)chemical reaction networks is closely related to determining the existence of Hopf bifurcation fixed points for positive values of variables and parameters in the corresponding dynamical systems. On the basis of a classical theorem of Orlando’s on pairs of purely imaginary eigenvalues of a matrix and using combinations of ideas of stoichiometric network analysis with ideas of tropical geometry we have developed (and implemented) a symbolic method for detecting Hopf bifurcation fixed points in chemical reaction networks (for some positive reaction rate parameters). With our fully algorithmic method we could successfully examine several networks of dimension up to 20, and and we have found Hopf bifurcation fixed points for several of them. 33 Normal forms and versal unfoldings in GLV WEINIAN ZHANG Yangtze Center of Mathematics and Department of Mathematics Sichuan University Chengdu, Sichuan 610064, P. R. China [email protected] In the case of the full zero degeneracy, the classic Poincare-Birhoff normal form theory is not available. In this talk a predator-prey system with such a degeneracy is considered. A new normal form is given for generalized Lotka-Volterra systems (abbreviated by GLV), which is employed to unfold the degenerate predator-prey system in GLV class. The universality of unfolding is proved by verifying the transversality. Further, all possible bifurcations at the degenerate equilibrium including transcritical bifurcation, Hopf bifurcation and heteroclinic bifurcation are discussed. References [1] Shigui Ruan, Yilei Tang, Weinian Zhang, Versal unfoldings of predator-prey systems with ratio-dependent functional response, J. Differential Equations 249 (2010) 1410-1435. [2] S.-N. Chow, C. Li, D. Wang, Normal Forms and Bifurcation of Planar Vector Fields., Cambridge University Press, Cambridge, 1994. 34 Stability and bifurcation analysis on a kind of hybrid system YEPENG XING Department of Mathematics Shanghai Normal University Rd. Guilin, 100, Shanghai, P.R. China [email protected] The mathematical descriptions of many hybrid dynamical systems can be characterized by impulsive differential equations. Impulsive dynamical systems can be viewed as a subclass of hybrid systems and consist of three elementsłnamely, a continuous time differential equation, which governs the motion of the dynamical system between impulsive or resetting events; a difference equation, which governs the way the system states are instantaneously changed when a resetting event occurs; and a criterion for determining when the states of the system are to be reset. Hybrid and impulsive dynamical systems exhibit a very rich dynamical behavior. In this talk, we are concerned with the stability of the origin and the existence of disconnected limit cycles. Also, we give examples to illustrate how the continuous subsystem and the discontinuous subsystem influence each other, i.e. how the impulses affect the behavior of the orbits to the continuous system. References [1] Yefeng He and Yepeng Xing, Poincar´ e Map and Periodic Solutions of First-Order Impulsive Differential Equations on Moebius Stripe, Abstract and Applied Analysis, Vol 2013. 35 [2] Z. Hu and M. Han, ”Periodic solutions and bifurcations of firstorder periodic impulsive differential equations,” International Journal of Bifurcation and Chaos in Applied Sciences and Engineering, vol. 19, no. 8, pp. 2515-2530, 2009. [3] D.D. Bainov and P. S. Simenov, Impulsive Differential Equations:Periodic Solutions and Applications, Longman Scientific and Technical, Harlow, UK, 1993. 36 Multiplicity of fixed points and growth of ε-neighborhoods of orbits ˇ C ´ 1 , MAJA RESMAN2 , VESNA ZUPANOVI ´2 ˇ PAVAO MARDESI C 1 Universit´e de Bourgogne, Department de Math´ematiques Institut de Math´ematiques de Bourgogne B.P. 47 870-21078-Dijon Cedex, France 2 University of Zagreb, Department of Applied Mathematics Faculty of Electrical Engineering and Computing Unska 3, 10000 Zagreb, Croatia [email protected] We study the relationship between the multiplicity of a fixed point of a function g, and the dependence on ε of the length of ε-neighborhood of any orbit of g, tending to the fixed point. The relationship ˇ between these two notions was discovered in Elezovi´c, Zubrini´ c, ˇ Zupanovi´ c in the differentiable case, and related to the box dimension of the orbit. Here, we generalize these results to non-differentiable cases. We study the space of functions having a development in a Chebyshev scale and use multiplicity with respect to this space of functions. With these new definitions, we recover the relationship between multiplicity of fixed points and the dependence on ε of the length of ε-neighborhoods of orbits in non-differentiable cases where results ˇ ˇ from Elezovi´c, Zubrini´ c, Zupanovi´ c do not apply. Applications include in particular Poincar´e map near homoclinic loop and Abelian integrals. 37 References ˇ ˇ [1] N. Elezovi´c, D. Zubrini´ c, V. Zupanovi´ c, Box dimension of trajectories of some discrete dynamical systems, Chaos Solitons Fractals 34(2) (2007) 244-252. ˇ [2] P. Mardeˇsi´c, M. Resman, V. Zupanovi´ c, Multiplicity of fixed points and ε-neighborhoods of orbits. Journal of Differential Equations 253 (2012) 2493-2514. 38 Contents Organizing Committee . . . . . . . . . . . . . . . . . . . . . 1 Invited Speakers . . . . . . . . . . . . . . . . . . . . . . . . . 2 Schedule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Abstracts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Index 40 39 Index Amel’kin V., 6 Aybar I., 7 Aybar O., 9 Chen X., 10 Ding W., 11 Dukari´c M., 13 Han M., 15 Liu L., 17 Liu Y., 18 Manos T., 20 Mencinger M., 22 Robnik M., 24 Romanovski V., 26 Ruffing A., 28 Vasileva E., 30 Weber A., 32 Xing Y., 34 Zhang W., 33 Zupanovi´c V., 36 40
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