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Structural health monitoring (SHM) of in-service structures is becoming increasingly important. The fundamental shear horizontal (SH 0 ) guided wave mode in plate-like structures shows great potential in damage detection due to its non-dispersive and in-plane vibration properties. In order to generate SH 0 waves, a practical Lorentz force-based electromagnetic acoustic transducer (EMAT) was introduced in this study using the flexible circumferential printed circuit (CPC). The designed principle of CPC-EMAT was similar to that of the circumferential magnet array (CMA)-based EMAT. However, the structure of the CMA-EMAT is complex, and it is difficult to assemble for generating high frequency and uniformly distributed omnidirectional SH 0 waves. Firstly, the performance of the CMA-EMAT with different numbers of magnets was investigated by finite element simulations. Then, the CPC was proposed to replace the CMA with an optimized designed on its size. The CPC-EMAT is easier to fabricate compared to the CMA-EMAT. Finally, experimental tests were conducted for systematic validations on the transducer properties. Simulation and experimental results show that the CPC-EMAT can successfully generate the desirable and acceptable omnidirectional SH 0 waves. The proposed CPC-EMAT is anticipated to find widespread application in SH-typed guided wave-based SHM., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Given that cities are the major contributors to carbon emissions, studying urban compactness (UC) and its impact on carbon emissions from energy consumption (CEECs) is crucial. This study calculated Hangzhou's township-level urban UC and CEECs using a hybrid subjective-objective weighted regression model on integrated panel datasets. By employing a geographically weighted regression (GWR) model, the spatio-temporal heterogeneity of the UC-CEEC relationship from 2006 to 2019 was uncovered. The results indicated an overall increase in UC, with significant variations across different counties. CEECs were higher in the central region, shifting eastward due to distinct urban development levels and policies. Moreover, the effects of various UC factors exhibited significant spatiotemporal inconsistency, with the impact intensity gradually diminishing. Additionally, the explanatory power of these factors declined and diversified over time. These findings emphasize the need for a comprehensive understanding of the relationship between UC and CEECs within the complex metropolitan environment and the importance of regulating their coordinated development. The research not only offers a more scientific approach to managing the growth of county-level cities and supporting balanced urbanization but also presents policy recommendations., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Author(s).)