Group 1 - The State Intellectual Property Office of China has published a patent application by China Railway First Survey and Design Institute Group Co., Ltd. and China Railway Construction Corporation Limited for a "Multi-level Reference Fusion Tunnel Construction Scene Positioning System and Method" [1] - The patent aims to achieve high-precision positioning of construction equipment and personnel during tunnel construction by utilizing a system that includes a central control system, static absolute reference network, positioning module, dynamic communication network, and external feature constraints [1] - The proposed system is designed to operate in stable construction areas and near the face of the tunnel, establishing an observable coordinate system at the boundary of these areas [1] Group 2 - China Railway First Survey and Design Institute Group Co., Ltd. was established in 1992, located in Xi'an, with a registered capital of 1.03 billion RMB [2] - The company has invested in 81 enterprises and participated in 5,000 bidding projects, holding 4 trademark records and 3,251 patent records [2] - China Railway Construction Corporation Limited was founded in 2007, based in Beijing, with a registered capital of approximately 13.58 billion RMB [2] - This company has invested in 126 enterprises and also participated in 5,000 bidding projects, holding 331 trademark records and 938 patent records [2]