CAREER: Single-Fidelity vs. Multi-Fidelity Computer Experiments: Unveiling the Effectiveness of Multi-Fidelity Emulation

职业：单保真度与多保真度计算机实验：揭示多保真度仿真的有效性

• 批准号: 2338018
• 负责人: Chih-Li Sung
• 金额: $ 42.36万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2024
• 资助国家: 美国
• 起止时间: 2024-06-01 至 2029-05-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2338018&HistoricalAwards=false
• 关键词: CAREER; Single; Fidelity; vs.; Multi

Computer models have become indispensable tools across diverse fields, enabling the simulation of complex phenomena and facilitating decision-making without costly real-world experiments. Traditionally, computer models are simulated using single, high-accuracy simulations, employing a high level of detail and resolution throughout. Recent advancements, however, have shifted attention towards multi-fidelity simulations, balancing computational cost and accuracy by leveraging various levels of detail and resolution in the simulation. A key question arises: is it more effective to use single-fidelity or multi-fidelity simulations? This is a question practitioners often confront when conducting computer simulations. The research aims to address this fundamental question directly, providing valuable insights for practical decision-making. By leveraging insights gained from computational cost comparisons, the research will enhance the ability to predict complex scientific phenomena accurately and has the potential to revolutionize fields such as engineering, medical science, and biology. The project contributes to outreach and diversity efforts, inspiring youth and increasing female representation in STEM research. Moreover, collaborations with diverse research groups, as well as involvement in the REU exchange program, provide opportunities to engage undergraduate students, nurturing their interest in research and encouraging them to pursue careers in STEM. Research findings will be disseminated through publications and conferences. The code developed will be shared to foster collaboration and encourage others to build upon these innovative methodologies.This research addresses the fundamental question of whether to conduct single-fidelity or multi-fidelity computer experiments by investigating the effectiveness of multi-fidelity simulations. It begins by examining the computational cost comparison between the two approaches, finding that multi-fidelity simulations, under certain conditions, can theoretically require more computational resources while achieving the same predictive ability. To mitigate the negative effects of low-fidelity simulations, a novel and flexible statistical emulator, called the Recursive Nonadditive (RNA) emulator, is proposed to leverage multi-fidelity simulations, and a sequential design scheme based on this emulator is developed, which maximizes the effectiveness by selecting inputs and fidelity levels based on a criterion that balances uncertainty reduction and computational cost. Furthermore, two novel multi-fidelity emulators, called "secure emulators," are developed, which theoretically guarantee superior predictive performance compared to single-fidelity emulators, regardless of design choices.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

计算机模型已经成为各个领域不可或缺的工具，能够模拟复杂现象，并在不进行昂贵的真实世界实验的情况下促进决策。传统上，计算机模型是使用单一的高精度模拟来模拟的，在整个过程中采用高水平的细节和分辨率。然而，最近的进展已经将注意力转移到多保真度模拟，通过利用模拟中的各种细节和分辨率来平衡计算成本和准确性。一个关键问题出现了：使用单保真度还是多保真度模拟更有效？这是从业者在进行计算机模拟时经常遇到的问题。该研究旨在直接解决这一基本问题，为实际决策提供有价值的见解。通过利用从计算成本比较中获得的见解，该研究将提高准确预测复杂科学现象的能力，并有可能彻底改变工程，医学和生物学等领域。该项目有助于外联和多样性工作，激励青年并增加STEM研究中的女性代表性。此外，与不同的研究小组的合作，以及参与REU交流计划，提供了机会，让本科生参与，培养他们对研究的兴趣，并鼓励他们追求在干事业。研究结果将通过出版物和会议传播。开发的代码将被共享，以促进合作，并鼓励其他人建立在这些创新的methods.This研究解决了是否进行单保真度或多保真度的计算机实验，通过调查多保真度模拟的有效性的基本问题。它首先检查两种方法之间的计算成本比较，发现多保真度模拟，在某些条件下，理论上可以需要更多的计算资源，同时实现相同的预测能力。为了减轻低保真度模拟的负面影响，提出了一种新的和灵活的统计仿真器，称为递归非加性（RNA）仿真器，利用多保真度模拟，并开发了基于此仿真器的顺序设计方案，通过选择输入和保真度水平的基础上，平衡不确定性降低和计算成本的标准，最大限度地提高了有效性。此外，还开发了两种新的多保真度仿真器，称为“安全仿真器”，无论设计选择如何，理论上都保证了与单保真度仿真器相比具有上级预测性能。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。