Yasumasa Nishiura
Professor／Unit Leader
Email nishiura(at)wpiaimr.tohoku.ac.jp
URL http://researchmap.jp/ynishiura/
Summary of Research｜Profile｜Career｜Prizes｜Papers｜MiscBibliography｜Conferences｜Academic Societies

Collision of localized traveling convection cells in binary fluids

Block copolymer melts and topological applications to material science

Behaviors of amoeba (Physarum plasmodium) in heterogeneous environments

Selfreplication, spatiotemporal chaos, and propagation failure
I am interested in collision dynamics in dissipative systems and behaviors of traveling spots in heterogeneous media. In what follows I will describe it very briefly.
Spatially localized dissipative structures are ubiquitous such as vortex, chemical blob, discharge patterns, granular patterns, and binary convective motion. When they are moving, it is
unavoidable to observe various types of collisions. One of the main questions for the collision dynamics is that how we can describe the large deformation of each localized object at collision and predict its output. The strong collision usually causes topological changes such as merging into one body or splitting into several parts as well as annihilation. It is in general quite difficult to trace the details of the deformation unless it is a very weak interaction. We need a change in our way of thinking to solve this issue. So far we may stick too much to the deformation of each localized pattern and become shrouded in mystery. We try to characterize the hidden mechanism behind the deformation process. It may be instructive to think about the following metaphor: the droplet falling down the landscape with valleys and ridges. The motion of droplets on a rugged landscape is rather complicated; two droplets merge or split at the saddle points and they may sink into the underground, i.e., annihilation. On the other hand, the profile of the landscape remains unchanged and in fact it controls the behaviors of droplets. It may be worth to describe the landscape itself rather than complex deformation, namely to find where is a ridge or a valley, and how they are combined to form a whole landscape. Such a change of viewpoint has been proposed recently claiming that the network of unstable patterns relevant to the collision process constitutes the backbone structure of the deformation process, namely the deformation is guided by the connecting orbits among the nodes of the network. Each node is typically an unstable ordered pattern such as steady state or timeperiodic solution. This view point is quite useful and can be applicable to various problems, especially, the dynamics in heterogeneous media is one of the interesting applications. External environments can be regarded as a heterogeneity for moving objects so that questions of adaptability in biological systems may fall in this category when they are reformulated in an appropriate way. See the recent works for more details.
I am serving as an editor of the following journals:
1.Physica D
2.European J.of Appl.Math.(Jan.1, 2008  Dec.30, 2011)
3.Chaos
4.SIADS (SIAM Journal on Applied Dynamical Systems)
Also I am currently working as the research director of JST Math Program: http://www.math.jst.go.jp/en/index.html
・Feb 2012 – Today Principal Investigator, Tohoku University WPIAIMR
・Apr 1995  Jan 2012 Professor, Leader of Research Group for Nonlinear Studies and Computation, Research Institute for Electronic Science, Hokkaido University
・Oct 2003  Sep 2005 Director, Research Institute for Electronic Science, Hokkaido University
・Apr 1991  Mar 1995 Professor, Applied Mathematics, Faculty of Integrates Arts and Science, Hiroshima University
・Apr 1989  Mar 1991 Associate Professor, Faculty of Science, Hiroshima University
・Apr 1982  Mar 1989 Associate Professor, Kyoto Sangyo University
・Apr 1978  Mar 1982 Lecturer, Kyoto Sangyo University
・Apr 2012 Prizes for Science and Technology, Ministry of Education, Culture, Sports, Science and Technology
・Sep 2002 The 2002 MSJ Autumn Prize, The Mathematical Society of Japan
【Papers】
・A mathematical mechanism for instabilities in stripe formation on growing domains
KeiIchi Ueda , Yasumasa Nishiura Physica D
Nonlinear Phenomena 241 3759 Oct 2011
・Heterogeneityinduced spot dynamics for a threecomponent reactiondiffusion system
Yasumasa Nishiura, Takashi Teramoto, Xiaohui Yuan
Communications on Pure and Applied Analysis 11(1) 307338 Sep 2011
・Collision dynamics in Dissipative Systems
Yasumasa Nishiura, Takashi Teramoto
Theoretical and Applied Mechanics Japan 59 1325 Mar 2011
・Timeperiodic traveling solutions of localized convection cells in binary fluid mixture
Takeshi Watanabe, Kazutaka Toyabe, Makoto Iima, Yasumasa Nishiura
Theoretical and Applied Mechanics Japan 59 211219 Mar 2011
・Mathematical model for contemplative amoeboid locomotion
KeiIchi Ueda, Seiji Takagi, Yasumasa Nishiura, Toshiyuki Nakagaki
Physical Review E 83(2) Feb 2011
・Pinned fronts in heterogeneous media of jump type
Peter van Heijster , Arjen Doelman, Tasso J Kaper, Yasumasa Nishiura, KeiIchi Ueda
Nonlinearity 24(1) 127157 Nov 2010
・Morphological characterization of the diblock copolymer problem with topological computation
Takashi Teramoto and Yasumasa Nishiura
Japan Journal of Industrial and Applied Mathematics 27(2) 175190 Sep 2010
・Rotational motion of traveling spots in dissipative systems
T.Teramoto, K.Suzuki, and Y.Nishiura,
Phys. Rev. E 80 046208 Oct 2009
・Pulse dynamics for reactiondiffusion systems in the neighborhood of codimension two singularity
ShinIchiro Ei, Yasumasa Nishiura and KeiIchi Ueda
Journal of Mathforindustry 1 9195 Oct 2009
・Dynamics of Particle Patterns in Dissipative Systems ― Splitting ･ Destruction ･ Scattering ―
Yasumasa Nishiura
SUGAKU EXPOSITIONS 22(1) 3755 Jun 2009
・Onset of Unidirectional Pulse Propagation in an Excitable Medium with Asymmetric Heterogeneity
Takashi Teramoto, Xiaohui Yuan, Markus Baer and Yasumasa Nishiura
Phys. Rev. E 79 046205104620516 Apr 2009
・Temperature accelerated dynamics study on migration process of oxygen defects in UO2
Takashi Ichinomiya, Uberuaga P. Blas, Sickafus E. Kurt, Yasumasa Nishiura, Mitsuhiro Itakura, Chen Ying, Yasunori Kaneta, Motoyasu Kinoshita
Journal of Nuclear Materials 384(3) 315321 Feb 2009
・Unstable periodic solution controlling collision of localized convection cells in binary fluid mixture
Makoto Iima and Yasumasa Nishiura
Physica D 238 449460 Feb 2009
・Information exchange between moving particles and defects
Takashi Teramoto, KeiIchi Ueda, Xiaohui Yuan and Yasumasa Nishiura
Proceedings of Information and Communications Technology 238249 Jan 2009
・A Nested Sequence of Transitions for Collision Dynamics in Dissipative Systems
Masaaki Yadome, KeiIchi Ueda, Takashi Teramoto, Masaharu Nagayama and Yasumasa Nishiura
Bulletin of the Institute of Mathematics, Academia Sinica (New Series) 3(4) 585601 Dec 2008
・Applications of computational homology to 3D morphology transitions
Yasumasa Nishiura
RIMS Kokyuroku 1614 166171 Oct 2008
・Intermittent Switching for Three Repulsively Coupled Oscillators
Kentaro Ito and Yasumasa Nishiura
Phys. Rev. E 77 036224 Mar 2008
・Indecisive behavior of amoeba crossing an environmental barrier
Seiji Takagi, Yasumasa Nishiura, Toshiyuki Nakagaki, Tetsuo Ueda, and KeiIchi Ueda
Proceedings of the international symposium on "Topological Aspects of Critical Systems and Networks" 8693 Apr 2007
・Minimumrisk path finding by an adaptive amoebal network
Toshiyuki Nakagaki, Makoto Iima, Tetsuo Ueda, Yasumasa Nishiura, Tetsu Saigusa, Atsushi Tero, Ryo Kobayashi and Kenneth Showalter
Phys. Rev. Lett. 99 068104 Apr 2007
・Heterogeneityinduced defect bifurcation and pulse dynamics for a threecomponent reactiondiffusion system
Xiaohui Yuan, Takashi Teramoto and Yasumasa Nishiura
Phys. Rev. E 75(3) 036220 Mar 2007
・Dynamics of traveling pulses in heterogeneous media of jump type
Yasumasa Nishiura, Yoshihito Oyama and Keiichi Ueda
Hokkaido Math.J.(2007) 36(1) 207242 Feb 2007
・Dynamics of traveling pulses in heterogeneous media
Yasumasa Nishiura, Takashi Teramoto, Xiaohui Yuan and KeiIchi Ueda
Chaos 17(3) 037104 Feb 2007
・Breathing Scattors in Dissipative Systems
Takashi Teramoto, KeiIchi Ueda and Yasumasa Nishiura
Progress of Theoretical Physics Supplement 161 364367 Jul 2006
・Resonance and the formation of deathspot in onedimensional FitzHughNagumo equations
Tatsuo Yanagita, Yasumasa Nishiura and Ryo Kobayashi
Progress of Theoretical Physics 161 393396 Apr 2006
・Scattering of traveling spots in dissipative systems
Y. Nishiura, T. Teramoto and K. Ueda
Chaos 15 047509047519 Dec 2005
・Chaotic pulses for discrete reaction diffusion systems
Yasumasa Nishiura, Daishin Ueyama and Tatsuo Yanagita
SIAM Journal on Applied Dynamical Systems 4(3) 733754 Sep 2005
・Edge bifurcations in singularly perturbed reactiondiffusion equations; a case of study
A.D. Iron Doelman and Yasumasa Nishiura
EQUADIFF 2003 Proceedings of the International Conference on Differential Equations 783788 Apr 2005
・Scattering of particlelike patterns in reactiondiffusion systems
KeiIchi Ueda, Takashi Teramoto and Yasumasa Nishiura
GAKUTO International Series, Mathematical Sciences and Applications 22 289303 Apr 2005
・Collision of localized travelingwave convection cells in binary fluid
Makoto Iima and Yasumasa Nishiura
GAKUTO International Series, Mathematical Sciences and Applications 22 289303 Apr 2005
・Threevariable reversible GrayScott model
Hitoshi Mahara, Nobuhiko J. Suematsu, Tomohiko Yamaguchi, Ohgane Kunishige, Yasumasa Nishiura and Masatsugu Shimomura
J.Chem.Phys. 121(18) 89688972 Nov 2004
・Phasedependent output of scattering process for traveling breathers
Takashi Teramoto, KeiIchi Ueda and Yasumasa Nishiura
Phys. Rev. E 69(4) 05622410562248 May 2004
・Destabilization of Fronts in a Class of Bistable Systems
Arjen Doelman, David iron and Yasumasa Nishiura
SIAM J. Math. Anal. 35(6) 14201450 Apr 2004
・Obtainning multiple separate food sources: Behavioural intelligence in the Physarum plasmodium
Toshiyuki Nakagaki, Ryo Kobayashi, Tetsuo Ueda and Yasumasa Nishiura
Proc. R. Soc. Lond. B 271 23052310 Apr 2004
・Some analytical results on the Gray Scott model
Dkhil Fathi, Logak Elisabeth and Yasumasa Nishiura
Asymptotic Analysis 39(34) 225261 Apr 2004
・Periodic Precipitation during Droplet Evaporation on a Substrate
Makiko Nonomura, Ryo Kobayashi, Yasumasa Nishiura and Masatsugu Shimomura
J. Phys. Soc. Jpn. 72(10) 24682471 Oct 2003
・Dynamic transitions through scattors in dissipative systems
Yasumasa Nishiura, Takashi Teramoto, KeiIchi Ueda
Chaos 13(3) 962972 Sep 2003
・Effects of guest hydrophobic molecule on stability of ordered meso structure of a surfactant/water system
Masayuki Imai, Takashi Teramoto, Ikuko Takahashi and Yasumasa Nishiura
J.Chem.Phys. 119(7) 38913895 Apr 2003
・Scattering and separators in dissipative systems
Yasumasa Nishiura, Takashi Teramoto and KeiIchi Ueda
Phys. Rev. E 67 05621010562107 Mar 2003
・Double gyroid morphology in a gradient system with nonlocal effects
Yasumasa Nishiura, Takashi Teramoto
J. Phys. Soc. Jpn. 71(7) 16111614 Apr 2002
・Spatiotemporal chaos for the GrayScott model
Yasumasa Nishiura and Daishin Ueyama
Physica D 150 137162 Dec 2001
・Global bifurcational approach to the onset of spatiotemporal chaos in reaction diffusion systems
Yasumasa Nishiura
Methods Appl. Anal. 8(2) 321332 Jun 2001
・2nsplitting or Edgesplitting A manner of splitting in dissipative systems
ShinIchiro Ei, Yasumasa Nishiura and KeiIchi Ueda
JJIAM 18(2) 181205 Jun 2001
・Strength in Numbers
Yasumasa Nishiura
The Japan Journal 6(5) 2831 Sep 2009
・Farfromequilibrium Dynamics
Yasumasa Nishiura
American Mathematical Society Mar 2002 ISBN:9780821826256
・Heterogeneityinduced spot dynamics in dissipative systems [Invited]
Yasumasa Nishiura, Takashi Teramoto
2012 SIAM Conference on Nonlinear Waves and Coherent Structures : Geometric methods for advectionreactiondiffusion systems  Part I of II Jun 2012
・The Japan Society for Industrial and Applied Mathematics
・ The Mathematical Society of Japan
・ SIAM(Society for Industrial and Applied Mathematics)
・ AMS(American Mathematical Society)