What are the central units in Yunnan 18?

According to relevant information, there are 18 central units in Yunnan: Yunnan PetroChina Kunlun Gas Co., Ltd.; China Petroleum Yunnan Petrochemical Co., Ltd.; Yunnan Aerospace Industry Co., Ltd.; North Night Vision Technology Group Co., Ltd.; China Railway Kunming Bureau Group Co., Ltd.; Yunnan Petroleum Branch of China Petrochemical Company; China Petroleum Yunnan Sales Branch; Kunming Marine Equipment Group Co., Ltd. is known to all of the above eight companies.