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Asphalt pavements in high-altitude and seasonally frozen regions of China encounter significant challenges that impact their stability and durability. This study aims to evaluate the performance of modified crumb rubber (MCR) asphalt mixtures under typical conditions of high-altitude seasonal frozen regions, specifically focusing on the effects of ultraviolet (UV) exposure and freeze–thaw cycling. Laboratory tests were designed to simulate UV irradiation and freeze–thaw cycling on asphalt mixtures, and then a series of tests were conducted on the pre-treated asphalt mixture specimens to investigate the effects on the performance including cohesion, high-temperature stability, low-temperature cracking resistance, water stability, and fatigue resistance. The MCR asphalt mixtures were tested in comparison to the Styrene–Butadiene–Styrene (SBS) modified asphalt and conventional crumb rubber modified asphalt mixtures. The test results indicated that MCR-modified asphalt mixture exhibited better cohesion and water stability than other tested mixtures. Under UV aging conditions, it showed a relatively slow performance degradation rate due to its unique composition that mitigates stress sensitivity. Also, when subjected to freeze–thaw cycling, the incorporation of MCR particles in the asphalt mixture resulted in delayed micro-crack propagation and a self-healing effect, thus mitigating its performance degradation rate compared to the other mixtures. The findings suggest that MCR MCR-modified asphalt mixture is a promising alternative for improving the durability of pavement in high-altitude and seasonally frozen regions. [ABSTRACT FROM AUTHOR]

Under the current economic situation, China’s economy is steadily moving from the stage of high-speed growth to that of high-quality development. while climate risks arising from global warming are receiving increasing media attention. Media attention has a profound impact on the perception and investment decisions of financial market participants. This paper constructs a climate risk index based on media attention and empirically investigates its relationship with stock volatility. It is found that the climate risk media index significantly affects stock volatility, which provides a theoretical basis for the regulation of financial asset price volatility. Through in-depth study of its influence mechanism, it can provide accurate decision support and risk management strategies for financial market stabilization.

Conventional approaches to sound localization and separation are based on microphone arrays in artificial systems. Inspired by the selective perception of the human auditory system, a multisource listening system which can separate simultaneous overlapping sounds and localize the sound sources in 3D space, using only a single microphone with a metamaterial enclosure is designed. The enclosure modifies the frequency response of the microphone in a direction‐dependent manner by giving each direction a characteristic signature. Thus, the information about the location and the audio content of sound sources can be experimentally reconstructed from the modulated mixed signals using a compressive sensing algorithm. Due to the low computational complexity of the proposed reconstruction algorithm, the designed system can also be applied in source identification and tracking. The effectiveness of the system in multiple real‐life scenarios is evaluated through multiple random listening tests. The proposed metamaterial‐based single‐sensor listening system opens a new way of sound localization and separation, which can be applied to intelligent scene monitoring and robot audition. [ABSTRACT FROM AUTHOR]