著者
石黒 真木夫
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.4, no.2, pp.125-138, 1994-06-15 (Released:2017-04-08)
参考文献数
15

It is established through a simulation study that if Kepler would have known AIC he could have used it to "prove" his theory. The reasons why the AIC works were sought and it was found that: 1. The AIC could be an un-biased estimate of the "mean expected log likelihood" of models, under mild conditions. 2. The "Mean expected log likelihood" is a reasonable criterion to compare statistical models. 3. The variance of the AIC is in effect small enough to allow the practical comparison of models. 4. If the bootstrap method is applicable, the variance can be estimated.
著者
緒方 秀教
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.27, no.4, pp.8-15, 2018 (Released:2018-03-31)
参考文献数
9

In this paper, we show an application of hyperfunction theory to numerical integration. It is based on the remark that, in hyperfunction theory, functions with singularities such as poles, discontinuities and delta impulses are expressed in terms of complex holomorphic functions. In our method, we approximate a desired integral by approximating the complex integral which defines the desired integral as an hyperfunction integral by the trapezoidal rule. Theoretical error analysis shows that the approximation by our method converges geometrically, which is due to the fact that the approximation by the trapezoidal rule of the integral of a periodic analytic function over one period interval or the integral of an analytic function over the whole infinite interval converges geometrically. Numerical examples show that our method is efficient especially for integrals with strong end-point singularities.
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.3, pp.218-225, 2008-09-25 (Released:2017-04-08)
参考文献数
21

2008年3月号に引き続いて,RSA暗号の格子理論に基づくいくつかの攻撃を紹介する.前回は,暗号の解読を1変数の法付きの方程式に帰着させ,この方程式を解くことによる攻撃のみを紹介した.本稿では,2変数以上の方程式に帰着される場合について紹介する.
著者
山中 卓 中川 秀敏 杉原 正顯
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.27, no.1, pp.5-12, 2017 (Released:2017-06-30)
参考文献数
18

This article comprehensively reviews some applications of Hawkes process to credit risk modeling with “contagion effect”. Credit risk is the risk associated with financial losses caused by credit events such as debtorsʼ defaults or credit rating transitions. Financial institutions are required to assess more accurately total credit risk of their large credit portfolios for better risk managements. As such, credit risk quantification models are desired to capture the effect of credit risk contagions, which may cause extreme financial losses. Hawkes process is a nonnegative integer-valued stochastic process which has been often used as a basic model for counting contagious events such as infectious diseases in epidemiology and earthquake in seismology. Similarly, modeling with Hawkes process enables us to easily capture some features of contagious credit events and thus to improve the performance of assessing total credit risks. In addition, a multivariate Hawkes process has capability of estimating mutual contagion effects among different industrial sectors. In this article, as for credit risk modeling and analyses with Hawkes processes, not only an introductory theoretical review but some illustrative results from some recent works of the present authors of empirical analyses are presented.
著者
曽 道智 茨木 俊秀
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.9, no.1, pp.12-27, 1999-03-15 (Released:2017-04-08)
参考文献数
31

We survey the recent research in the field of cake divisions and their procedures. The question is how to divide a cake among n players, so that a certain fairness is achieved, where players have individual measures on the cake, and each player only knows his own measure. The model has very wide applications, such as dividing up the property in an estate, and even in determining the border in an international dispute. We first review mathematical definitions of various concepts of fairness. Although the existence of fair divisions is proved under some mathematical conditions, their dividing procedures are not known for all cases. We summarize several existing division procedures and classify them according to their methods and purposes. Finally, we mention some related topics and describe possible future research directions.
著者
萩原 茂樹 米崎 直樹
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.17, no.4, pp.291-301, 2007-12-26 (Released:2017-04-08)
参考文献数
10

暗号プロトコルの解析は,確率的多項式時間チューリング機械を用いる計算論的手法と,Dolev-Yaoモデルに基づく記号論的手法がそれぞれ独立に研究されてきた.記号論による解析は,抽象レベルの解析とみなせ簡潔で分かりやすい一方,記号論による解析結果と計算論による解析結果の対応が明らかでなかった.この問題に対してAbadiとRogawayは,完全な対称鍵暗号方式を前提としてメッセージの見た目の等価性を記号論的に定義し,メッセージが等価ならばそれらは計算論的に識別不可能であること,すなわち記号論によるメッセージの識別不可能性の計算論的意味づけに対する健全性を示した.さらに,MicciancioとWarinschiはその完全性を示している.本稿では,これら内容を中心に関連する研究を含め紹介を行う.
著者
新井 朝雄
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.3, no.4, pp.292-306, 1993-12-15 (Released:2017-04-08)
参考文献数
46

Mathematical aspects of quantum field theory are reviewed. The topics included are: canonical quantization of classical fields, functional integral method, Schwinger's functional derivative equation, methods and results of constructive quantum field theory, Lamb shift in quantum electrodynamics, supersymmetric quantum field theory and related aspects.

1 0 0 0 OA 制御と数理

著者
木村 英紀
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.1, no.1, pp.2-16, 1991-03-15 (Released:2017-04-08)

The relevance of mathematics in control theory is described. The role of mathematics in the early development of control theory is reviewed with the emphasis on the models of controlled objects. The relation between the operational calculus and the classical control theory is discussed. The contact between control theory and mathematics became more and more wider and deeper especially after the emergence of modern control theory in 1960. Some specific aspects of the mathematical problems posed by control theory are reviewed. Possible future directions of the mathematics/control interface is described in conjunction with robustness issues of control systems design.
著者
行木 孝夫
出版者
日本応用数理学会
雑誌
応用数理 (ISSN:09172270)
巻号頁・発行日
vol.13, no.2, pp.125-136, 2003
参考文献数
45

ライフゲームに代表されるセルオートマトンは簡明な定義からなる系でありながら多様な挙動を示すものとして広く研究されてきた。本稿ではエルゴード理論、力学系のごく簡単な導入を行い、エントロピーや変分原理など関連する事項を整理するとともに力学系としてのセルオートマトンの特徴を明らかにする。