Mining machinery manufacturing; Manufacture of automobile parts and accessories; Engineering and technical research and experimental development; New-material technology research and development; Automobile parts R&D; Technical services, technical development, technical consulting, technical exchange, technology transfer and promotion; Machinery and equipment R&D; Software development; Sales of mechanical parts and components; Sales of mechanical equipment; Sales of electronic products; Machining of mechanical parts and components; Repair of metal products; General equipment repair; Special-purpose equipment repair; Maintenance of electronic and mechanical equipment (excluding special equipment); Machinery and equipment leasing; Import and export of goods and technologies; Internet-of-Things application services; Sales of coal and coal-related products.