Metallurgy refers to the process and process of extracting metals or metal compounds from minerals and making metals into metal materials with certain properties by various processing methods. Metallurgy has a long history of development, from the Stone Age to the subsequent Bronze Age, and then to the large-scale development of modern steel smelting. The history of human development is fused with the history of metallurgy.

Shipbuilding is a specialized profession that predates recorded history. Ship building and ship repair is a mixed industry of commerce and military, generally referred to as the "maritime industry", in the early primitive society, primitive ancestors lived on fishing, hunting and fishing, and the scope of activity was limited to the area very close to the water.

Hvac is an integral part of the building, including: heating, ventilation, air conditioning three aspects. Engaged in the field of building environment control, building energy conservation and intelligent technology of building facilities, with air-conditioning, heating, ventilation, building water supply and drainage, gas supply and other public facilities system, building heat supply system and building energy conservation design, construction, commissioning, operation management capabilities and building automation department.