Technical development and sales of electronic components, integrated circuits, optoelectronic products, semiconductors, solar products, instrument accessories, digital TV playback products and communication products; technical development and sales of dryers, industrial dehumidifiers, purification equipment, electromechanical equipment, and refrigeration equipment; research and development of intelligent transportation products Development; door-to-door installation, R&D and sales of road transportation facilities; technical development and sales of conference public broadcasting equipment and avionics equipment; sales of agricultural machinery, auto parts, motorcycles and their parts, electric lighting equipment, and electric motors; e-commerce; domestic trade; and import and export business. Wholesale and sales of primary agricultural products; wholesale and sales of clothing, textiles, knitwear, and daily necessities; wholesale and sales of cultural supplies and sporting goods; wholesale and sales of building materials; wholesale and sales of machinery and equipment, hardware products, and electronic products; wholesale and sales of jewelry and handicrafts. Sales of metal materials; mechanical design and sales; design and sales of scientific instruments. R&D, sales, technical consulting, and technical services of Class I and Class II medical devices; sales of disinfectants, disinfection products, and sanitary products; investment in medical projects; sales of Class III medical devices;