Inoguchi Junichi

J-GLOBAL         Last updated: Jan 16, 2020 at 02:58
Inoguchi Junichi
University of Tsukuba
Faculty of Pure and Applied Sciences
Job title
Research funding number

Published Papers

Inoguchi, Jun-ichi; Munteanu, Marian Ioan
Inoguchi, Jun-ichi;Naitoh, Hiroo
Hokkaido Mathematical Journal   48(2) 385-406   Jun 2019   [Refereed]
We study the Grassmann geometry of surfaces when the ambient space is a 3-dimensional non-unimodular Lie group with left invariant metric. This work together with our previous papers yield a complete classification of Grassmann geometry of orbit t...
Inoguchi, Jun-ichi;Kajiwara, Kenji;Matsuura, Nozomu;Ohta, Yasuhiro
Journal of Integrable Systems   4(1)    Jun 2019   [Refereed]
Elasticae in similarity geometry and their discretization.
井ノ口, 順一;梶原健司;三浦憲二郎;朴炯基;Schief, Wolfgang
Reports of RIAM Symposium No.29AO-S7 New Trends in Nonlinear Waves - Theory and Applications -   29AO-S7 61-68   Mar 2018   [Refereed]
弾性エネルギーの臨界点である平面曲線は弾性曲線とよばれる.弾性曲線はmKdV 方程式と深く関連し,実際,平面曲線の等周変形を記述するmKdV 方程式の進行波解から定まる曲線が弾性曲線である.本稿では相似幾何学の枠組みを用いて工業意匠設計で用いられている対数型美的曲線(LAC)とその一般化を考察し,それらが平面曲線の等角変形を記述するBurgers 方程式の定常解として特徴付けられること,および適当なエネルギーの臨界点として定式化できることを報告する.この結果は,LAC が弾性曲線の相似幾何...
Inoguchi, Jun-ichi;Ziatdinov, Rushan;Miura, Kenjiro T.
Japan Journal of Industrial and Applied Mathematics   36(1) 239-259   Jan 2019   [Refereed]
The class of log-aesthetic curves includes the logarithmic spiral, clothoid, and involute of a circle. Although most of these curves are expressed only by an integral form of the tangent vector, it is possible to interactively generate and deform ...
Inoguchi, Jun-ichi;Seiichi, Udagawa
Journal of Physics Communications   2(11)    Nov 2018   [Refereed]
The purpose of the present paper is to give an explicit form of the finite gap solutions to the Tzitzeica equation (2D Toda equation of type A_2^2) in terms of Riemann theta function. We give explicit expressions of proper affiene spheres derived ...
Inoguchi, Jun-ichi;Lee, Sungwook
Proceedings of the American mathematical Society   136(6) 2209-2216   May 2008   [Refereed]
The normal Gauss map of a minimal surface in the model space Sol of solvegeometry is a harmonic map with respect to a certain singular Riemannian metric on the extended complex plane.
Parallel surfaces in the motion groups E(1,1) and E(2)
Inoguchi, Jun-ichi;Van der Veken, Joeri
Bulletin of the Belgian Mathematical Society - Simon Stevin   14(2) 321-332   Jun 2007   [Refereed]
We give a classification of parallel surfaces in the groups of rigid motions of Minkowski plane and Euclidean plane, equipped with a general left-invariant metric. Our result completes the classification of parallel surfaces in the eight three-dim...
Inoguchi, Jun-ichi;Van der Veken, Joeri
Geometriae Dedicata   131(1) 159-172   Feb 2008   [Refereed]
We complete the classification of surfaces with parallel second fundamental form in all three-dimensional homogeneous spaces.
Inoguchi, Jun-ichi;Naitoh, Hiroo
Hokkaido Mathematical Journal   38(3) 427-496   Aug 2009   [Refereed]
We study the Grassmann geometry of surfaces when the ambient space is a 3-dimensional unimodular Lie group with left invariant metric, that is, it is one of the 3-dimensional commutative Lie group, the 3-dimensional Heisenberg group, the groups of...
The hidden symmetry of chiral fields and the Riemann-Hilbert problem, revisited
井ノ口, 順一
京都大学数理解析研究所講究録   2071 1-16   Apr 2018
We generalize the Ueno-Nakamura theory and the Uhlenbeck-Segal theory for harmonic maps of Riemann surfaces into compact semi-simple Lie groups to those of (affine) harmonic maps into general Lie groups with torsion free bi-invariant connection in...
井ノ口, 順一
2018年度精密工学会春季大会シンポジウム資料集   54-57   Mar 2018
Inoguchi, Jun-ichi;Kajiwara, Kenji;Miura, Kenjiro T.;Sato, Masayuki;Schief, Wolfgang K.;Shimizu, Yasuhiro
Computer Aided Geometric Design   61 1-5   Feb 2018   [Refereed]
In this paper we consider the log-aesthetic curves and their generalization which are used in CAGD. We consider those curves under similarity geometry and characterize them as stationary integrable flow on plane curves which is governed by the Bur...
Miura, Kenjiro T.;Suzuki, Sho;Gobithaasan, R.U.;Usuki, Shin;Inoguchi, Jun-ichi;Sato, Masayuki;Kajiwara, Kenji;Shimizu, Yasuhiro
Computer-Aided Design and Applications   15(2) 256-263   Oct 2017   [Refereed]
A curve is considered fair if it consists of continuous and few monotonic curvature segments. Polynomial curves such as Bézier and B-spline curves have complex curvature function, hence the curvature profile may oscillate easily with a little twea...
Inoguchi, Jun-ichi;Munteanu, Marian Ioan
Tohoku Mathematical Journal   69(1) 113-128   Apr 2017   [Refereed]
It is an interesting question whether a given equation of motion has a periodic solution or not, and in the positive case to describe it. We investigate periodic magnetic curves in elliptic Sasakian space forms and we obtain a quantization princip...
井ノ口, 順一
津田塾大学 数学・計算機科学研究所報   38 68-80   Mar 2017
Inoguchi, Jun-ichi;Taniguchi, Tetsuya;Seiichi, Udagawa
Journal of Integrable Systems   1(1)    Dec 2016   [Refereed]
Dorfmeister, Josef F;Inoguchi, Jun-ichi;Kobayashi, Shimpei
Advances in Mathematics   298 207-253   Aug 2016   [Refereed]
We generalize the Uhlenbeck-Segal theory for harmonic maps into compact semi-simple Lie groups to general Lie groups equipped with torsion free bi-invariant connection.
Dorfmeister,Josef F.;Inoguchi,Jun-ichi;Kobayashi,Shimpei
Asian Journal of Mathematics   20(3) 409-448   Jul 2016   [Refereed]
Dorfmeister, Josef F.;Inoguchi, Jun-ichi;Kobayashi, Shimpei

Books etc

A First Course to Partial differentiation
井ノ口, 順一
現代数学社   Sep 2019   ISBN:9784768705162
解析学百科II 可積分系の数理
井ノ口,順一 (Part:Contributor, 幾何学と可積分系)
朝倉書店   Mar 2018   ISBN:9784254117
A First Course to Lie Algebras
井ノ口, 順一
現代数学社   Feb 2018   ISBN:9784768704714
A First Course to Lie Groups
井ノ口, 順一
現代数学社   Jul 2017   ISBN:9784768704707
Surface Geometry and Integrable Systems
井ノ口, 順一
Oct 2015   ISBN:9784254117

Conference Activities & Talks

Harmonic map into Lie groups, revisited [Invited]
井ノ口, 順一
The Joint International Meeting of the Chinese mathematical Society and American Mathematical Society   11 Jun 2018   
Curve flows, integrable systems and industrial design [Invited]
井ノ口, 順一
Integrable Geometry at Bayrischzell   18 May 2018   
対数型美的曲線の相似幾何学的定式化 [Invited]
井ノ口, 順一
AIMaP数学応用シンポジウム:精密工学と幾何学の新たな出会い   17 Mar 2018   公益社団法人 精密工学会
Elasticae in similarity geometry and their discretization.
井ノ口, 順一;梶原健司;三浦憲二郎;朴炯基;Schief, Wolfgang
非線形波動研究の新潮流 .理論とその応用   11 Nov 2017   
Grassmann geometry of surfaces in 3-dimensional homogeneous spaces [Invited]
井ノ口, 順一

Research Grants & Projects

Global construction of constant mean curvature surfaces in terms of contact geometry and loop groups
Project Year: Apr 2009 - Mar 2012
We showed that minimal surfaces in hyperbolic 3-space are obtained as projections of f-holomorphic curves in the semi-Riemannian homogeneous contact space SL(2,C)/U(1). By using the appropriate loop group splitting, for any prescribed potential, w...
Research on constructions of constant mean curvature surfaces in terms of conformal geometry and loop groups
Grant-in-Aid for Scientific Research(C)
Project Year: Apr 2006 - Mar 2009