广东宏大：矿服业务包括露天矿山、地下矿山以及混装一体化三大核心业务

Group 1 - The core business of the company includes three main areas: open-pit mining, underground mining, and mixed integrated services [1] - The subsidiary Lianshao Construction focuses on underground mining operations, providing mining engineering construction, equipment installation, and mining engineering services to large and medium-sized underground mine owners [1]