著者
國廣 昇 太田 和夫
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:24321982)
巻号頁・発行日
vol.18, no.1, pp.23-29, 2008-03-25 (Released:2017-04-08)
参考文献数
17
被引用文献数
1
著者
高安 秀樹
出版者
一般社団法人 日本応用数理学会
雑誌
日本応用数理学会年会予稿集 日本応用数理学会年会予稿集
巻号頁・発行日
pp.99, 2002-09-18 (Released:2003-03-18)

本講演では、経済物理(エコノフィジックス)の研究最前線の様子をレヴューする。需要の安定均衡が物理的にはありえないことなど、裁定機会が存在すること、ミクロな市場価格の変動からマクロなインフレーションの時間発展の方程式を導出することなど、これまでに得られている基本的な成果を紹介する。また、応用研究の現状を踏まえて、今後の展望を議論する。
著者
稲葉 寿
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:09172270)
巻号頁・発行日
vol.30, no.1, pp.14-21, 2020

<p>The basic reproduction number <i>R</i><sub>0</sub> in structured population dynamics is defined as the spectral radius of the generation evolution operator induced by the integral kernel of the renewal integral equation. If the basic population dynamics is described by the evolutionary system associated with a nonautonomous differential equation, the generation evolution operator is calculated from the infinitesimal generator of the evolution semigroup induced from the evolutionary system. Using the basic reproduction number defined by the generation evolution operator, we can examine existence and stability of total orbits of nonlinear nonautonomous system, in which the total orbit is given as a fixed point of the evolution semigroup. Thus the idea of <i>R</i><sub>0</sub> is uniquely extended to the threshold value for extinction and persistence of population in time-heterogeneous environments.</p>
著者
冨岡 亮太
出版者
一般社団法人 日本応用数理学会
雑誌
日本応用数理学会論文誌 (ISSN:24240982)
巻号頁・発行日
vol.23, no.3, pp.485-515, 2013-09-25 (Released:2017-04-08)

本サーベイ論文では機械学習を中心とした分野で近年注目されているスパース性を導く様々な正則化法を加法的なスパース正則化と構造的なスパース正則化に分類し,それぞれに対する最適化法を議論する.前者は,条件数の悪化に対して頑健な手法が重要であり,相対拡張ラグランジュ法を紹介する.一方,後者に対しては,線形演算で表現される構造とスパース正則化項を分離することを可能にする手法として交互方向乗数法を紹介する.
著者
岩崎 義光
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:24321982)
巻号頁・発行日
vol.5, no.3, pp.209-229, 1995-09-18 (Released:2017-04-08)
参考文献数
22

The theory of grain boundary structure is reviewed from the mathematical point of view. High-order twins are mathematically introduced and developed up to the 4th order twins in the case of cubic crystals. The coincidence-site lattice, 0-lattice and DSC lattice are considered with emphasis on their algebraic aspects. Some applications of high-order twins and coincidence-site boundaries are discussed to point out these importance in the field of material sciences and industries.
著者
横山 直人 高岡 正憲
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:24321982)
巻号頁・発行日
vol.26, no.4, pp.15-23, 2016-12-22 (Released:2017-03-25)
参考文献数
29

Elastic-wave turbulence has been used for a testbed for the weak turbulence theory, since it can be examined by numerical and laboratory experiments. The elastic-wave turbulence has distinctive characteristics as a wave turbulence system, one of which is the coexistence of the weak and strong turbulence. Recent researches on the elastic-wave turbulence are reviewed, not restricted to the weak turbulence properties, with focusing on energy transfers under large-scale external forcing.
著者
今井 桂子
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:24321982)
巻号頁・発行日
vol.6, no.1, pp.29-39, 1996-03-15 (Released:2017-04-08)
参考文献数
14

Triangulations have been one of main topics in computational geometry and other fields in recent years. In the planar case, any pair of triangulation can be transformed to each other by a sequence of so-called Delaunay flips, and enumeration of all triangulations can be done by reverse search. However, there is no known result for higher-dimensional triangulations. Recently, some types of triangulations have been found to bridge geometric issues and algebraic ones. Regular triangulations are of such a type, and form a meaningful wide subclass of triangulations of points in general dimensions. Especially, regular triangulations have a close connection with discriminants of polynomials in several variables. Restricting ourselves to the class of regular triangulations in any dimensions, we know that such triangulations correspond to vertices of some polytope, and we can enumerate all regular triangulations by reverse search.
著者
吉村 健司 高橋 一弘
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:24321982)
巻号頁・発行日
vol.7, no.1, pp.2-23, 1997-03-17 (Released:2017-04-08)
参考文献数
12

An electric power system is a large-scale energy system composed of a lot of equipment such as power generating units, transmission lines, voltage transformers and power demand loads. It is also a very complex system including generator's electromagnetic dynamics and many control system's characteristics to maintain a constant level of voltage and systemfrequency. Eigenvalue analysis is one of the methods to handle a power system stability problem associated with the system dynamic perfomance. This paper describes mathematical models of power system components and also explains a calculation technique of eigenvalue analysis to evaluate a large -scale power system stability. Its application for improving stability enhancement using eigenvalue sensitivity is also described in this paper.
著者
大島 邦夫 保福 一郎 伊奈川 晃
出版者
一般社団法人 日本応用数理学会
雑誌
日本応用数理学会論文誌 (ISSN:24240982)
巻号頁・発行日
vol.4, no.3, pp.259-274, 1994-09-15 (Released:2017-04-08)
参考文献数
11

In general, the cumulative curves of the bugs agree with Gompertz curve or Logistic curve in many software developments. Using these curves, we will be able to forcast the total number of the bugs when we estimate them within the certain interval. But many experiments show us that those estimates do not coincide with the actual number of bugs. In our experimental data, the se curves usually have more than two steps(a step means an interval or a point where the socond derivative is zero in terms of a continuous function), In this paper, we will study the following four problems ; ・to give the analogy for debugging processes and to find several reasons why such curves appear by means of Gray box method. ・to define a continuous function which is called a modified Gompertz curve that can be expressed by more than two steps. ・to fit the modified Gompertz curve for such a cumulative curve which has more than two steps. ・to forcast total number of bugs on the first step by fitting the modefied Gompertz curve.
著者
小澤 一文
出版者
一般社団法人 日本応用数理学会
雑誌
日本応用数理学会論文誌 (ISSN:24240982)
巻号頁・発行日
vol.3, no.4, pp.451-464, 1993-12-15 (Released:2017-04-08)
参考文献数
12

We propose a simple procedure for setting the efficient starting values of the Durand-Kerner iteration, which finds all zeros α_i(i = 1, ・・・, n) of a polynomial of degree n simultaneously. In our new procedure, the starting values are located on the circle centered at β with radius γ_<gm>where β = 1/nΣ^^n__<i=1>α_i, and γ_<gm> is the geometric mean of the deviations |α_i - β|. The computational cost for this procedure is extremely cheap compared with that for Aberth's procedure. Moreover, the various numerical examples show that our new method reduces the number of iterations tremendously over any other ones, particularly when some of the deviations |α_i - β| are large.
著者
安藤 英俊 藤木 史朗 鳥山 孝司
出版者
一般社団法人 日本応用数理学会
雑誌
応用数理 (ISSN:24321982)
巻号頁・発行日
vol.20, no.2, pp.107-116, 2010-06-25 (Released:2017-04-08)
参考文献数
4

Many Preconditioning algorithms for Krylov subspace methods are developed and well tested on parallel computing environment like PC clusters, but performance of those methods on GPU differs from those on clusters. Although incomplete LU decomposition is the most popular preconditioner for Krylov subspace methods on CPU, its implementation on GPU was never successful because of the sequential nature of the algorithm. By using C for CUDA environment, we have efficiently implemented ILU(0) on GPU. We have also implemented and evaluated various kinds of preconditioning methods for Krylov subspace solvers on GPU, including Jacobi, Red-Black Gauss-Seidel, Line-by-Line and ILU(0). ILU(0) preconditioner turned out to be most efficient and fastest among these preconditioners when solving Poisson equation.
著者
谷口 哲也
出版者
一般社団法人 日本応用数理学会
雑誌
日本応用数理学会論文誌 (ISSN:24240982)
巻号頁・発行日
vol.25, no.4, pp.285-307, 2015-12-25 (Released:2017-04-08)

円分体やその相対類数は重要な整数論的対象として19世紀から認識されてきており,円分体の理論は20世紀以降,類体論や岩澤理論へと発展した.本論文では,相対類数の計算の現状について,計算範囲,手法(行列式,modular arithtmetic,有限体上のFFT,2次元FFT),計算量を概括し,今後の展望を述べる.