This monograph focuses on the **JUN¿E series transmitters** developed for ultra¿high temperature and severe corrosive industrial environments, based on nearly a decade of Sino¿Japanese technical accumulation and engineering practice. It systematically constructs a complete theoretical and technical system for extreme¿condition measurement, covering core innovations in high¿temperature adaptation, corrosion protection, multi¿parameter integration, and structural optimization. Supported by 517 industrial projects, 17 core patents, and applications in over 30 state¿owned and central enterprises, the book verifies product performance through rigorous experiments and certifications, filling domestic technological gaps in high¿temperature and corrosion¿resistant measurement. The work summarizes the engineering applications of the JUN¿E series in power, chemical, new energy, steel, and environmental protection sectors, providing customized solutions for molten salt, corrosive media, and high¿pressure coupling scenarios. It also analyzes the global market landscape, industrialization paths, and major challenges, while putting forward¿looking research directions and industry development suggestions. The book aims to promote the import substitution of high¿end measuring instruments, enhance industrial autonomy, and support the high¿quality development of China's advanced manufacturing and green energy industries.