Vortex flowmeters are subjected to the influence of noise so their measurement accuracy can not be ensured in industrial fields and the turn-down ratio is limited .

涡街流量计易受噪声影响，现场测量精度得不到保证， 量程 比受限。

Digital signal processing methods have many advantages e.g. strong anti-interference ability high precision and large turn-down ratio and they are implemented by DSP chips commonly .

数字信号处理方法具有抗干扰能力强、精度高、 量程 比 宽等优点，一般采用DSP芯片来实现。

Practice proves that the utilization of the idle high-pressure equipment for technical renovation with alcohol hydrocarbylation cuts down the investment cost and is also high in turn-down ratio little work is needed for maintenance of the equipment and the economic benefit is evident .

实战证明，利用闲置的高压设备进行醇 烃化技术改造，不仅投资省，而且操作弹性大、设备维护工作量小，具有明显的经济效益和环保效益。