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This paper presents a near‐field focused metasurface design method for microwave hyperthermia. Utilizing full‐wave electromagnetic simulation, a novel dual‐layer metasurface unit with the following characteristics is developed: transmission efficiency higher than −1 dB, adjustable transmission phase from 0° to 360°, and insensitivity to the polarization and incident angle of the incoming wave. Leveraging phase compensation theory, the units at different positions in the array to achieve near‐field focusing functionality is meticulously designed. To further optimize transmission efficiency, the transmission phase of the central unit of the metasurface to 76° is tuned. When applying this near‐field focused metasurface to microwave hyperthermia, the electromagnetic and thermal effects in biological tissues is conducted simulations and experiments to analyzed. The results demonstrate that the proposed metasurface can effectively focus microwave energy, achieving efficient microwave transmission in pork tissue and generating localized high temperatures in the target area. This research introduces new design concepts and implementation strategies for the development of microwave hyperthermia technology. [ABSTRACT FROM AUTHOR]

Although mixed use is an emerging strategy that has been widely accepted in urban planning for promoting neighbourhood vibrancy, there is no consensus on how to quantitatively measure the mix and the effects of mixed use on neighbourhood vibrancy. Shannon entropy, the most commonly used diversity measurement in assessing mixed use, has been found to be inadequate in measuring the multifaceted, multidimensional characteristics of mixed use. And lack of data also makes it difficult to find the relationship between mixed use and neighbourhood vibrancy. However, the recent availability of new sources including mobile phone data and Point of Interest (POI) data have made it possible to develop new indices of mixed use and neighbourhood vibrancy to analyse their relationships. Taking advantage of these emerging new data sources, this study used the numbers of mobile phone users in a 24-hour period as a proxy of neighbourhood vibrancy and used POIs from a navigation database to develop a series of mixed-use indicators that can better reflect the multifaceted, multidimensional characteristics of mixed-use neighbourhoods. The Hill numbers, a unified form of diversity measurement used in ecological literature that includes richness, entropy, and the Simpson index, are used to measure the degrees of mixed use. Using such fine-grained data sets and the Hill numbers allowed us to obtain better insights into the relationship between mixed use and neighbourhood vibrancy. Four models varying in POI measurements that reflect different dimensions of mixed use were presented. The results showed that either POI density or entropy can explain approximately 1% of neighbourhood vibrancy, while POI richness contributes significantly in improving neighbourhood vibrancy. The results also revealed that the entropy has limitations as a measure for representing mixed use and demonstrated the necessity of adopting a set of more appropriate measurements for mixed use. Increasing the number of POIs has limited power to improve neighbourhood vibrancy compared with encouraging the mixing of complementary POIs. These exploratory findings may be useful for adjusting mixed-use assessments and to help guide urban planning and neighbourhood design. [ABSTRACT FROM AUTHOR]