Standard and accepted procedures in programs and systems analysis. The abbreviations, symbols, and their meanings developed for particular systems and programs. 程序系统,种标准,括特系统程序制缩写、符号其含。
The basic facilities, services, and installations needed for the functioning of a community or society, such as transportation and communications systems, water and power lines, and public institutions including schools, post 础设施正常运需设施,装设备等,通通系统,供,校、局监狱等