GA/T 1487-2018 公安交通管理窗口排队叫号及服务评价系统通用技术要求 General technical requirements for queuing and service evaluating system of public security traffic management
BS EN ISO 3580-2017 焊接耗材用于耐蠕变钢的手动金属电弧焊的覆盖电极 分类 Welding consumables. Covered electrodes for manual metal arc welding of creep-resisting steels. Classification