一般二维码生成工具都借助于第三方API，如：谷歌API；但由于众所周知的原因第三方API往往不太稳定，所以导致经常无法使用！ 红鸟二维码，借助于纯PHP类，既不依赖于API也不依赖于网络环境，彻底避免了此类问题的发生！ -Usually two-dimensional code generation tools by means of a third-party API, such as: Google API but for reasons known third-party API

二维非定常激波管问题数值模拟方法的TVD(A numerical method for two-dimensional unsteady shock tube problems TVD)