Mechanical equipment research and development; Sales of power electronic components; Electronic components wholesale; Electronic components retail; Sales of electronic products; Machinery and equipment sales; Retail of photographic equipment and telescopes; Camera and equipment sales; Retail of computer hardware, software and auxiliary equipment; Wholesale of computer hardware, software and auxiliary equipment; Domestic trade agency; Import and export of goods; Technology import and export; Technical service, technology development, technology consultation, technology exchange, technology transfer, technology dissemination. (Except for projects subject to approval according to law, the company shall independently carry out business activities according to law with its business license