In typical mountainous coal mines in Yunnan, Guizhou and Sichuan provinces, the complex "air-ground-ground" collaborative monitoring data has established a classification method that includes indicators such as static geological background, dynamic deformation and hydrogeochemical data. Subsequently, the research revealed the evolution mechanism of the combined disaster chain of surface deformation and sudden water outburst in old mines, and established a three-level early warning indicator system of background, status and impending disaster. The application in a certain mining area in Liupanshui, Guizhou Province demonstrated that this system can effectively identify high-risk areas, with the coincidence rate of identifying "unstable areas" exceeding 85%, and the physical mechanism of water chemical indicators was verified through hydrogen and oxygen isotope analysis. This integrated system provides a systematic technical solution for risk management and disaster prevention and mitigation in mining areas with similar complex geological conditions.

Urban rail transit systems have been the pillar of an urban transportation network, and their safety of operation is critical to the welfare of the populace. Nevertheless, the vast distances and intricate environments through which these rail networks pass are vulnerable to many encroachment risks, such as illegal buildings, fallen trees, landslides, and sinking pipelines and roads. The complexity and fast-changing nature of these threats, coupled with the possibility of sudden occurrence, is a serious problem. Manual monitoring is the main feature of conventional inspection techniques, which are constrained in efficiency, coverage, and data uniformity, making them unsuitable for high-frequency, detailed monitoring. These weaknesses may result in catastrophic outcomes; the failure to identify a hazard on time narrows the time of emergency response, increasing the probability of service failures and accidents. In addition, the absence of unified time and space references makes it difficult to obtain real-time data in emergencies, disrupting command efficiency and responsibility and eventually raising operational costs and weakening the system's resilience.

The evaluation of the geological environment carrying capacity of mines is crucial for achieving sustainable development and risk management of mines. This study proposes a spatio-temporal evaluation model that integrates remote sensing ecological indices and geological safety indices to take into account the surface ecological status of the mining area and underground geological safety. This method is based on the theoretical framework of "state-pressure-response", integrates multi-source remote sensing, InSAR, geology and other multi-temporal data, constructs RSEI through principal component analysis, builds GSI through analytic hierarchy process, and determines the weights using entropy weight method for comprehensive evaluation, generating the spatial distribution of carrying capacity. Taking the Pingshuo mining area in Shanxi Province as an example, the application of the model (from 2015 to 2024) shows that the high carrying capacity vulnerable areas present a "point-line-plane" composite feature, which is highly correlated with mining activities and structural zones. The verification indicates that the overall accuracy of the model is 86.4%, and it can identify 35% of the emerging deformation and ecological degradation risk areas that were underestimated by traditional methods, providing an effective spatialization tool for dynamic monitoring and precise control of the mining area environment.

Deep ultraviolet (DUV) LEDs are critical for applications like water purification, surface disinfection, and biomedical sensing. However, conventional p-GaN contact layers exhibit strong optical absorption, causing extremely low external quantum efficiency and light extraction efficiency. Transparent AlGaN tunnel junctions have been proposed as an effective solution to eliminate this parasitic absorption while maintaining efficient hole injection. This paper provides a systematic review of transparent AlGaN tunnel junctions as a solution to the p-GaN absorption bottleneck in DUV LEDs. By synthesizing recent studies on Al composition engineering, doping strategies, thickness optimization, and interface control, the design principles of optimized AlGaN tunnel junction structures are summarized. Remaining challenges and future research directions are also discussed, including material growth limitations, balance between transparency and conductivity, long-term reliability, novel materials, new nanostructures, photonic structure integration, and machine learning-assisted design optimization. This review offers a comprehensive understanding of transparent AlGaN tunnel junctions, promoting the development of next-generation high-efficiency DUV LEDs.

Recently, more and more digital twin technologies are getting attention in managing and operating urban metros. The fact that integrating time-monitor data like a metro digital twin right now has chances to improve its operation and dependability. This essay is mostly about the applications of digital twins for the metro system: infrastructure monitoring and operation management. Digital twin, at the infrastructure level, can be utilized in observing the structure inside the metro tunnel to see if there is a dangerous situation. For example, a swelling on Earth. After applying our collected data to a predictive analysis, this will offer us an early warning and allow preventive maintenance. In terms of operation, a digital twin system would help people to monitor the operation of metro network, which means smoother passenger flow. Although the metro system's digital twin technology has great benefits, problems like data integration, reliability of the whole system and its security still need to be solved. More studies and practices need to take place to make sure that digital twin tech is employed safely and correctly on future metros.

Against the backdrop of energy conservation, emission reduction and green low-carbon development, traditional syngas production processes are plagued by high energy consumption and excessive greenhouse gas emissions. In contrast, the photocatalytic CO2reduction technology, driven by solar energy, enables the conversion of CO2into syngas. It combines the values of environmental protection and resource recycling, thus becoming a current research hotspot. In the design of high-efficiency single-atom catalysts (SACs) for photocatalytic CO2reduction, the microenvironment design of single-atom metal sites is of crucial importance. Based on this, in this work, a series of Co-coordinated COF catalysts named Triazine-COF-Co-Cl were synthesized to regulate the Co-coordination microenvironment for enhancing syngas production via photocatalytic CO2reduction. Among them, the Triazine-COF-Co-AA catalyst with the best performance achieved a syngas production rate of 381.7 mmol g−1h−1, and the H2/CO molar ratio could be continuously adjusted in the range of 1-3, which is sufficient to cover the commonly used syngas ratio range in industry. This paper improves the performance of COF-based photocatalysts for syngas production via CO2reduction through the regulation of Co-coordination environment, and provides ideas and certain data support for the research on solving energy and environmental problems and reducing CO2emissions.

A digital twin-based framework is developed in this paper for road condition monitoring and predictive maintenance, aiming to tackle the inefficiencies of traditional road inspection methods and the practical dilemmas in the operation of complex road infrastructure systems. Road maintenance management is confronted with prominent challenges including the spatial complexity of road networks, the nonlinear evolution of pavement damage, and the heterogeneity of multi-source monitoring data. To solve these practical problems, this research designs a three-layer digital twin architecture composed of physical space, data interaction space and virtual space, and puts forward three targeted innovative design strategies. First, autonomous inspection vehicles integrated with a multi-sensor system are deployed to realize continuous and real-time data acquisition under normal traffic conditions, without interrupting the regular road operation. Second, a unified data integration platform is constructed to standardize the format of heterogeneous monitoring data, thereby improving the interoperability and data sharing efficiency of different road monitoring systems. Third, a robotic maintenance system is designed to support targeted and automated repair operations, with maintenance decisions generated based on the predictive analysis results of the digital twin model. The case test results show that the proposed digital twin framework can significantly improve the efficiency of road condition inspection and provide reliable technical support for the formulation of predictive maintenance strategies for road infrastructure. Overall, the framework developed in this study provides a practical approach for improving road maintenance using digital twin technology. It shows potential for supporting more efficient and scalable maintenance processes in real-world applications.

Dynamic Random-Access Memory (DRAM), as the core component of storage systems, offers a simple structure, high storage density, low unit cost, and fast read and write speeds. It is a key support for smart Internet of Things (IoT) devices to achieve low power consumption and high-density upgrades. Low-power, high-density DRAM technology has become a current research hotspot in the field of storage. In sense amplifiers, research focuses on offset compensation, noise immunity, and pre-sensing technology to improve accuracy under low-voltage operation and reduce power consumption. Using advanced Complementary Metal-Oxide-Semiconductor (CMOS) processes can reduce leakage current, lower operating voltage, and enhance process compatibility for high-density integration. 3D stacking technology breaks the physical limitations of planar DRAM through vertical integration that improves DRAM density and data retention capability. Starting from the above three major modules, this paper systematically reviews representative research achievements in low-power, high-density DRAM over the past few years. It analyzes the innovation paths and performance optimization effects of each module, and summarizes the development trends of low-power DRAM technology.

Maritime shipping business has been an important event in global trade, but it is still marred by serious challenges such as high prices, environmental effects, hazards on ships and port congestion. With the use of technologies like Internet of Things, cloud computing, and artificial intelligence gaining an ever-increasing significance in the Industry 4.0 epoch, smarter and more efficient shipping solutions are getting recognized as an issue of even greater importance. In that case, the digital twin technology that is the development of virtual depictions of physical systems in real-time opportunity presents great potential to overcome these difficulties. The review is a collection of research on the topic carried out during the last five years to explore how digital twins are applied to smart ships, ports, and logistics systems and determine the main trends in technologies, application patterns, and gaps in research. It also addresses the way, in which digital twins can influence the forthcoming alteration of the maritime industry. Thus, the study of the digital twin technology in marine shipping is both theoretical and practical.

This article clarifies the operational mechanism of moisturizers on the stratum corneum of the skin, explains how they affect skin moisture content and barrier function, and provides a theoretical basis for formula design, offering more effective moisturizing solutions for people with damaged skin barriers, such as those with sensitive skin, dry skin, eczema, and aging skin. It also helps the public choose moisturizers suitable for their skin to maintain skin health. This article explores the principle of action of skin moisturizers and adopts a literature analysis method. This article shows that skin moisturizers can not only alleviate skin dryness but also maintain the integrity of the skin barrier and improve resistance to external factors, thereby protecting skin health. Through in-depth exploration of the mechanism of action of moisturizers, it can provide theoretical support for the scientific design of cosmetic formulas, the research and development and optimization of medical moisturizing products, and also provide a basis for the rational selection of moisturizing products.