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The purpose of this study is to prepare a chemically stable superhydrophobic coating with remarkable mechanical properties and concrete protective properties.

One synthetic step was adopted to prepare superhydrophobic coating. The process and product were analyzed and confirmed by fourier transform-infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), water contact angle (WCA), transmission electron microscopy (TEM), scanning electron microscope (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The mechanical properties were confirmed by tensile test. The concrete protective properties were confirmed by solution immersion test and rapid chloride migration coefficient test.

MSiO₂ nanoparticles (NPs) were chosen to enhance the hydrophobicity of fluorosilicone coatings. With a 4:1 mass ratio of fluorosilicone resin and MSiO₂ NPs, the coatings show superhydrophobicity with a WCA of 156° and a SA of 3.1°. In addition, the tensile mechanical property was improved, and the chloride ion diffusion coefficient was decreased significantly after the addition of MSiO₂ NPs.

This new fluorosilicone coating hybrid by MSiO₂ NPs could be applied as a concrete protective layer with properties of self-cleaning, antifouling, etc.

Introduction of MSiO₂ NPs hybrid to prepare fluorosilicone coating with superhydrophobicity on concrete surface has not been systematically studied previously.

The purpose of the paper is to analyze the impact of coupling on the distribution of the magnetic field and study the characteristics of the magnetic flux density in the transmission process of the magnetic coupling resonant wireless power transmission (MCR-WPT) system, which provides guidance on the design of the WPT system.

In this study, a finite element simulation analysis was conducted and a three-dimensional (3D) electromagnetic field measurement platform was used.

It is shown that the distribution of the magnetic field, as well as the position of maximum magnetic flux density, will change when the coils are coupled. The simulation results of the magnetic field distribution, as well as the transmission performance, are different from those in practice. It cannot describe the actual performance of WPT system.

A 3D electromagnetic field measurement system and the host computer software are designed to help optimize the simulation and carry out more accurate and efficient research. The 3D electromagnetic field measurement system can be used to study the distribution of the spatial electromagnetic field, influencing factor, exposure and interoperability between different coils.

This paper explores the role of traditional Chinese medicine (TCM) as a tourism recovery drawcard to boost China's inbound tourism after COVID-19.

This paper employed a mixed method involving a cross-disciplinary literature review along with reflections from experts in TCM and health communication to inform tourism management. Specifically, this paper examines TCM and its potential benefits as a medical tourism drawcard to combat COVID-19. The selected literature focusses on the image and merits of TCM to frame how this medical philosophy can be used to position China as a tourist destination. Reflections on the use of TCM as a tourism marketing tool can guide promotional strategies from the Chinese government and destination managers during and after COVID-19.

The Chinese government, the tourism industry (e.g. destination managers), the media and tourists must focus on three aspects of the role of TCM: to provide medical benefits to travellers amid COVID-19 and beyond, elevate China as a destination for global medical tourists and be leveraged as a tool for economic recovery.

The paper builds a tourism recovery framework for stakeholders to adopt tailored TCM communication strategies to boost its inbound tourism programme.

This paper is the first academic paper to review TCM comprehensively and critically in relation to China tourism and post-COVID-19 recovery measures.

This study aims to investigate the factors responsible for substrate cracking reliability problem in through-glass vias (TGVs), which are critical components for glass-based 2.5 D integration.

Numerical models were used to examine the driving force for substrate cracking in glass interposers due to stress coupling during heating. An analytical solution was used to demonstrate how the energy release rate (ERR) for the glass substrate cracking is affected by the via design and the mismatch in thermal strain. Then, the numerical models were implemented to investigate the design factors effects, such as the pitch distance, via diameter, via pattern, via design, effect from a stress buffer layer and the interposer materials selection on the susceptibility to substrate cracking.

ERR for substrate cracking was found to be directly proportional to the via diameter and the thermal mismatch strain. When a via pattern is implemented for high-density integration, a coupling in the stress fields was identified. This coupling effect was found to depend on the pitch distance, the position of the vias, and the via arrangement, suggesting a via pattern-dependent reliability behavior for glass interposers. Changing the design of the via to an annular shape or a substrate-cored via was found to be a promising approach to reduce the susceptibility to substrate cracking compared to a fully filled solid via. Also, the use of a stress buffer layer, an encouraging design prospect presented for the first time for TGVs in this study, was found to significantly reduce cracking. Finally, alternative via and substrate materials showed lower tendency for substrate cracking, indicating that the reliability of glass interposers can be further enhanced with the implementation of such new materials.

This study signifies the first attempt to comprehensively evaluate the susceptibility to crack formation in glass interposers during heating. Therefore, this study provides new perspectives on how to achieve a significant potential reliability improvement for TGVs.

The purpose of this paper is to propose an effective and efficient numerical method that can consider natural frequency in multi-material topology optimization (MMTO) and which is scalable for complex three-dimensional (3D) problems.

The optimization algorithm is developed by combining custom FORTRAN code for MMTO with the open-source software Mystran, which is used as a finite element analysis (FEA) solver. The proposed algorithm allows the designer to shift the fundamental frequency of the design beyond a defined frequency spectrum from the initial designing phase. The methodology is formulated in a smooth and differentiable manner, with the sensitivity expressions, required by gradient-based optimization solvers, presented.

Natural frequency constraint has been successfully implemented into MMTO. The use of open-source software Mystran as an FEA solver in the algorithm provides ability to solve complex problems. Mystran offers powerful built-in functions for eigenvalue extraction using methods like Givens, modified Givens, inverse power and the Lanczos method, which provide the ability to solve complex models. The algorithm is successfully able to solve both two- and three-material MMTO jobs for two-dimensional and 3D geometries.

Natural frequency constraint consideration into topology optimization is very challenging due to three common issues: localized eigenmodes, mode switching and high computational cost. The proposed algorithm addresses these inherent issues, implements natural frequency constraint to MMTO and solves for complex models, which is hardly possible using conventional methods.