Hydrogen is hailed as a plentiful and clean energy source, which holds promise as a substitute for fossil fuels, particularly when produced through solar water splitting. However, its volatile and explosive nature necessitates stringent safety measures throughout its production, transportation, and utilization. This study analyzes hydrogen gas leakage detection by using various sensors such as ultrasonic, electrochemical, metal oxide (MOX), catalytic, and fiber Bragg grating sensors. Various sensor technologies are developed for hydrogen leak detection, and each offers unique advantages and challenges. Fiber optic sensors, leveraging changes in light interference, provide explosion resistance and durability, while ultrasonic sensors detect leaks through sound wave analysis, albeit with limited commercial application in hydrogen environments. Schlieren imaging offers real-time visualization of hydrogen behavior, predominantly in laboratory settings. Electrochemical sensors enable reliable detection through electrochemical interactions, while MOX sensors exhibit sensitivity and ease of manufacturing, albeit with challenges related to cross-sensitivity and response times. Catalytic gas sensors and thermal conductivity sensors offer alternative detection methods, with the former catalyzing hydrogen combustion for detection and the latter measuring temperature differentials upon exposure to hydrogen. The analysis of hydrogen leakage incidents highlights the importance of robust safety measures in hydrogen infrastructure and facilities. The integration of innovative sensing technologies with automated shutdown systems and robust materials has enhanced the reliability and efficiency of leak detection systems. Continued research and cooperation are essential to address residual challenges and further enhance the safety of hydrogen utilization in various industrial sectors.

As different artificial intelligence (AI) techniques continue to evolve, power systems are undergoing significant technological changes with the primary goal of reducing computational time, decreasing utility and consumer costs and ensuring the reliable operation of an electrical power system. AI techniques compute large amounts of data at a faster speed than numerical optimization methods with higher processing speeds. With these features, AI techniques can further automate and increase the performance of power systems. This paper presents a comprehensive overview of diverse AI techniques that can be applied in power system operation, control and planning, aiming to facilitate their various applications. We explained how AI can be used to resolve system frequency changes, maintain the voltage profile to minimize transmission losses, reduce the fault rate and minimize reactive current in distributed systems to increase the power factor and improve the voltage profile.

The creation of smart cities has benefited greatly from the quick advancement of sensor and actuator technology. The basis of data-driven urban environments is supported by these technologies, which seamlessly connect with the Internet of Things (IoT). This in-depth review paper explores the crucial part that sensors and actuators play in the development of smart cities, covering important topics such as technological kinds, data security, regulatory frameworks, and future possibilities. The review begins by explaining the importance of sensors and actuators in the Internet of Things (IoT) connections that serve as the framework for smart cities. Additionally, it sheds light on the wide range of sensors designed for different IoT applications as well as the variables affecting their service life, highlighting how crucial precision and durability are. Actuators are examined in detail to clarify how it might be used to create smarter cities. Actuators are the dynamic counterparts of sensors. This review discusses data security in big data exchange among actuators, legal foundations for smart city development, and key elements for creating a smart city. It highlights the benefits of advanced actuator technology and sensor integration, and emerging trends like AI-driven urban management and blockchain-enhanced data security. The paper serves as a guide for researchers, policymakers, and urban planners. The graphical abstract below illustrates the multifaceted advancements in sensor and actuator technologies, showcasing their pivotal role in shaping smarter, more sustainable cities. Graphical Abstract