Structural Health Monitoring (SHM) is a relatively new branch of civil engineering that focuses on assessing the health status of infrastructure, such as long-span bridges. Using a broad range of in-situ monitoring instruments, the purpose of the SHM is to help engineers understand the behaviour of structures, ensuring their structural integrity and the safety of the public. Under the Integrated Applications Promotion (IAP) scheme of the European Space Agency (ESA), a feasibility study (FS) project that used the Global Navigation Satellite Systems (GNSS) and Earth Observation (EO) for Structural Health Monitoring of Long-span Bridges (GeoSHM) was initiated in 2013. The GeoSHM FS Project was led by University of Nottingham and the Forth Road Bridge (Scotland, UK), which is a 2.5 km long suspension bridge across the Firth of Forth connecting Edinburgh and the Northern part of Scotland, was selected as the test structure for the GeoSHM FS project. Initial results have shown the significant potential of the GNSS and EO technologies. With these successes, the FS project was further extended to the demonstration stage, which is called the GeoSHM Demo project where two other long-span bridges in China were included as test structures. Led by UbiPOS UK Ltd. (Nottingham, UK), a Nottingham Hi-tech company, this stage focuses on addressing limitations identified during the feasibility study and developing an innovative data strategy to process, store, and interpret monitoring data. This paper will present an overview of the motivation and challenges of the GeoSHM Demo Project, a description of the software and hardware architecture and a discussion of some primary results that were obtained in the last three years.

Summary Global Navigation Satellite System (GNSS) positioning technology has had widespread applications in the structural health monitoring as its overall performance has improved significantly in the last two decades. It is capable of providing timely and accurate structural vibration information such as dynamic displacements and modal frequencies at higher performance than traditional accelerometers. The studies summarized in this paper focus on the improvement of the multi‐sensors and multi‐constellation data acquisition techniques, the improvement of multiple approaches for erroneous noise mitigation, and innovative modal parameter identification methods. We also detailed the applications of GNSS on the deformation monitoring for towers, chimneys, tall buildings, and bridges. With continuous enhancements in the algorithm and hardware of GNSS, it is expected that the application of GNSS technology can be expanded to other fields such as bridge cable‐force measurements and bridge weight‐in‐motion as well as structural deformation monitoring.

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ZnO rod arrays were directly grown on In2O3/Sn (ITO)-coated glass substrates without needing a preprepared ZnO seed layer by aqueous chemical growth (ACG) using an equimolar aqueous solution of Zn(NO3)2·6H2O and C6H12N4. By further varying the substrates such as glass, Pt/glass, and Au/glass, other assembly patterns of ZnO architectures (rodlike, flowerlike, urchinlike, and stelliform crystals) were also obtained. The possible growth mechanisms for different assembly patterns dependent on the substrate were proposed. It was revealed that both the inherent highly anisotropic structure of ZnO and the surface energy minimization of different substrates play crucial roles in determining final morphologies of ZnO architectures. In addition, the photoluminescence (PL) properties of ZnO architectures on various substrates were investigated at room temperature.