Detection of the Non-Gaussian Phenomena in Civil Engineering Field and Development of Their Analytical Methods

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K04242
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22020:Structure engineering and earthquake engineering-related
• Research Institution: Kobe Gakuin University
• Principal Investigator: SATO Tadanobu 神戸学院大学, 現代社会学部, 研究員 (00027294)
• Co-Investigator(Kenkyū-buntansha): 木本 和志 岡山大学, 環境生命科学学域, 准教授 (30323827)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 非ガウス現象 / アンラップ操作を行わない地震動位相の計算法 / 位相平均勾配の確率特性 / フーリエ変換実数部のモデル化 / 因果性に基づく虚数部の再現 / ヒル ベルト変換 / 観測記録からの確率特性の抽出 / 多数の加速度時刻歴の模擬

Outline of Final Research Achievements

The purpose of this research is to discover non-Gaussian phenomena and a method for analyzing the discovered phenomena. We have developed a stochastic process transcend the modern stochastic theory. As a representative of non-Gaussian phenomena we concentrate on the earthquake motion phase, first we develop a method to obtain the continuous phase with respect to the circular frequency without unwrap procedure. Then we define the mean phase gradient (MPG), which is approximation of a group delay time. Regardless of the interval of circular frequency the probability density function (PDF) of MPG is expressed by a unique PDF expressed by the Levy-flight distribution, which means the MGP has a fractal characteristic.
We develop a new stochastic process, in which the PDF of MGP obeys to the Levy-flight distribution. To do this we also defined the Levy-flight nose process.

Free Research Field

土木工学における非ガウス現象の抽出とモデル化

Academic Significance and Societal Importance of the Research Achievements

本研究は、土木工学における非ガウス現象を抽出し、その模擬法を確立することにある。もし成功すれば、物理や工学現象の世界における新しい事象の解明に画期的な成果になるとともに、今後の物理・工学事象の解明に広く利用されることになる。