CAREER: Higher-Order Methods for Nonlinear Stochastic Structural Dynamics

职业：非线性随机结构动力学的高阶方法

• 批准号: 1652044
• 负责人: Michael Shields
• 金额: $ 50万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-06-01 至 2023-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1652044&HistoricalAwards=false
• 关键词: CAREER; Higher; Order; Methods; Nonlinear

This Faculty Early Career Development (CAREER) grant is to study the influence of real, observable dynamic loads that are randomly varying in nature (e.g. wind velocity and pressure) on structures that exhibit complex behavior. This study will enable more accurate structural modeling that will inform improved design practices for high performance structures that operate for longer service lives at lower cost. The research will be applicable to structures of all sorts where efficiency is critical and loads are highly unpredictable, ranging from civil structures to aircraft, automobiles, ships, and spacecraft. This award supports fundamental research to simulate the nature of these randomly varying loads in greater detail than has been previously possible. Leveraging these studies, the response of different classes of structures subjected to such environments will be investigated with the ultimate aim of optimizing performance. The award will also support the development of new undergraduate research modules, which will be made publicly available, designed to introduce students to careers in research and teach basic research skills that are useful beyond academia. Many physical phenomena are characterized by complex stochastic processes that exhibit strongly non-Gaussian and nonlinear features. This project will build new methods for characterizing and synthesizing these higher-order stochastic processes that will be used as excitation for various nonlinear structural systems. The nonlinear structural systems studied herein - including hyperelastic, elastic-plastic, and chaotic systems - are especially sensitive to the nature of the stochastic excitation and may exhibit drastically different structural behavior based on seemingly minor changes in the stochastic excitation. Currently, the sensitivity of nonlinear structural response to various features of the stochastic excitation is not well understood. This research will extensively study this sensitivity for different classes of nonlinear structural systems and develop new topology optimization model to enhance structural performance.

该教师早期职业发展（CAREER）补助金旨在研究自然随机变化的真实的、可观察的动态载荷（例如风速和压力）对表现出复杂行为的结构的影响。这项研究将实现更准确的结构建模，从而为改进高性能结构的设计实践提供信息，从而以更低的成本实现更长的使用寿命。该研究将适用于效率至关重要且载荷高度不可预测的各种结构，从土木结构到飞机、汽车、船舶和航天器。该奖项支持基础研究，以比以前更详细地模拟这些随机变化的负载的性质。利用这些研究，将研究不同类别的结构在此类环境下的响应，最终目的是优化性能。该奖项还将支持新的本科生研究模块的开发，这些模块将公开发布，旨在向学生介绍研究职业，并教授对学术界以外有用的基本研究技能。许多物理现象的特点是复杂的随机过程，表现出强烈的非高斯和非线性特征。该项目将建立新的方法来表征和综合这些高阶随机过程，这些过程将用作各种非线性结构系统的激励。本文研究的非线性结构系统（包括超弹性、弹塑性和混沌系统）对随机激励的性质特别敏感，并且可能基于随机激励中看似微小的变化而表现出截然不同的结构行为。目前，非线性结构响应对随机激励的各种特征的敏感性尚不清楚。这项研究将广泛研究不同类别非线性结构系统的敏感性，并开发新的拓扑优化模型以提高结构性能。

项目成果

UQpy: A general purpose Python package and development environment for uncertainty quantification

UQpy：用于不确定性量化的通用 Python 包和开发环境

• DOI: 10.1016/j.jocs.2020.101204
• 发表时间: 2020-08-24
• 期刊: J. Comput. Sci.
• 作者: Audrey Olivier;Dimitris G. Giovanis;B. Aakash;Mohit Chauhan;Lohit V;anapu;anapu;M. Shields
• 通讯作者: M. Shields

Simulation of non-stationary and non-Gaussian random processes by 3rd-order Spectral Representation Method: Theory and POD implementation

用三阶谱表示方法模拟非平稳和非高斯随机过程：理论和 POD 实现

• DOI: 10.1016/j.ymssp.2022.109150
• 发表时间: 2021-09-28
• 期刊: Mechanical Systems and Signal Processing
• 影响因子: 8.4
• 作者: Lohit V;anapu;anapu;M. Shields
• 通讯作者: M. Shields

Uncertainty quantification (UQ) as an archetype for research: Integrating UQ into undergraduate research education

不确定性量化（UQ）作为研究原型：将 UQ 纳入本科生研究教育

• DOI: 10.1109/fie43999.2019.9028397
• 发表时间: 2019-10
• 期刊: IEEE
• 作者: Aakash, B.S.;Perez;Ibrahim, A.;Shields, M.D.
• 通讯作者: Shields, M.D.

3rd-order Spectral Representation Method: Simulation of multi-dimensional random fields and ergodic multi-variate random processes with fast Fourier transform implementation

三阶谱表示方法：通过快速傅里叶变换实现多维随机场和遍历多元随机过程的模拟

• DOI: 10.1016/j.probengmech.2021.103128
• 发表时间: 2021-03-14
• 期刊: Probabilistic Engineering Mechanics
• 影响因子: 2.6
• 作者: Lohit V;anapu;anapu;M. Shields
• 通讯作者: M. Shields