with the advantages of weatherproof, comprehensive, long-term, continuous, real-time et al, the deep sea exploration technology is capable of observing the internal process and relationship of the deep ocean. it is the basic technology and information acquisition method for the national marine security, resource and energy development, environmental monitoring and disaster warning and forecasting. sdioi has successfully developed a batch of equipment and sensors such as seafloor observatory network key device, expendable temperature-depth profile measurement system, salinity sensor, fiber optic temperature-depth sensor. this equipment is widely used in the field of marine environment monitoring, disaster forecasting and early warning, exploration and exploitation of marine resources, national defense and security, effectively promoting the development of china's marine economy.