Innovative Signal Analysis Techinques for Health Monitoring Systems and Sensing Materials

健康监测系统中的一个重要环节是数据处理技术，包括相应的理论和算法，从大量的测量数据中提取相关信息，快速评估结构的状态。许多会议都指出，这种联系是民用基础设施的传感器健康监测系统中最薄弱的环节之一。该项目旨在开发基于希尔伯特-黄谱分析的创新和高效的数据处理技术，用于民用基础设施的损坏检测、状况评估和完整性评估。将为以下方面制定新的有效方法：（i）线性结构的损伤检测和系统识别，（ii）确定传感器的最佳布置，（iii）非线性结构的损伤检测和系统识别，包括保守（弹性）和非保守结构（滞后）非线性结构，以及（iv）在极端事件（如强震）后对结构损坏的初步评估，所有这些都是基于希尔伯特-黄谱分析。此外，还将开发希尔伯特-黄光谱分析计算机软件模块，用于集成到基于传感器的民用基础设施监测系统中。香港及中国，根据《中美地震工程与减灾科学技术合作研究议定书》。基本上，将在香港理工大学（HPU）进行民用基础设施系统的先进健康监测系统研究;将在中国哈尔滨工业大学（HIT）开发先进的传感器技术;将在中国工程力学研究所（IEM）研究传感器的传感材料;将在美国圣母大学（UND）开发先进和智能阻尼和设备;并且将在加州大学欧文分校（UCI）开发新型数据处理技术。此外，N. E.美国国家航空航天局戈达德飞行中心的Huang是Hilbert-Huang谱分析的先驱，他将与我们合作，为民用基础设施的基于传感器的监测系统开发新的数据处理技术。Hilbert-Huang谱分析可用于开发强大的技术，利用该技术可以提取测量响应信号的固有非平稳和非线性特征。这项研究的结果不仅对基于传感器的结构健康监测系统的数据分析技术的发展水平，而且对美国合作研究机构将要开发的传感器技术，香港和中国。

One important link in the health monitoring system is the data processing techniques, including the corresponding theory and algorithms, to extract relevant information for a rapid assessment of the state of the structure from a large amount of measured data. Such a link has been pointed out during many conferences as one of the weakest link in the sensor-based health monitoring system of civil infrastructures. This project is aiming at the development of innovative and efficient data processing techniques, based on the Hilbert-Huang spectral analysis, for the damage detection, condition assessment and integrity evaluation of civil infrastructures. New and efficient methodologies will be developed for: (i) damage detection and system identification of linear structures, (ii) determination of the optimal placement of sensors, (iii) damage detection and system identification of nonlinear structures, including conservative (elastic) and nonconservative (hysteretic) nonlinear structures, and (iv) preliminary assessment of structural damages after an extreme event, such as strong earthquakes, all based on the Hilbert-Huang spectral analysis. Further, Hilbert-Huang spectral analysis computer software modules for incorporating into the sensor-based monitoring systems of civil infrastructures will be developed.This proposal is a part of an integrated collaborative research effort among U.S.A., Hong Kong and P.R.C., under the US-China Protocol for Scientific and Technical Cooperative Research on Earthquake Engineering and Hazard Mitigation. Basically, advanced health monitoring system research for civil infrastructure systems will be conducted at Hong Kong Polytechnic University (HPU); advanced sensor technology will be developed at Harbin Institute of Technology (HIT), China; sensing materials for sensors will be investigated at Institute of Engineering Mechanics (IEM), China; advanced and smart damping and devices will be developed at University of Notre Dame (UND); and novel data processing techniques will be developed at the University of California, Irvine (UCI). In addition, Dr. N. E. Huang of NASA Goddard Flight Center, who is the pioneer of the Hilbert-Huang spectral analysis, will collaborate with us in the proposed research efforts to develop novel data processing techniques for sensor-based monitoring systems for civil infrastructures.The research proposed herein is unique, which is different from all the data analysis techniques currently available. The Hilbert-Huang spectral analysis can be used to develop powerful techniques with which intrinsic nonstationary and nonlinear characteristics of the measured response signals can be extracted. The results of this research are expected to have a significant impact not only on the state-of-the-technology in data analyses for the sensor-based health monitoring systems of structures but also on the sensor technologies to be developed by the collaborative research institutions in U.S.A., Hong Kong and China.