美国 SonTek      
美国YSI集团成立于1948年，总部位于美国俄亥俄州，是目前世界上唯一一家同时掌握水质与流速流量测量技术的集团公司。作为国际上领先的水质、流速流量监测仪器制造商，以世界领先的传感器技术为核心，不断推出先进的水质和流量监测产品。YSI集团拥有YSI和SonTek两大品牌，共四条主要的产品线：YSI水质分析仪、YSI多参数水质监测系统、SonTek/YSI声学多普勒流速流量测量系统、YSI集成系统（前称Endeco/YSI系统）。
    
Founded in 1992 on the premise that precision water velocity measurement should be practical, affordable, and easy, SonTek/YSI today offers the widest variety of acoustic Doppler instrumentation on earth.

Since our invention of the Acoustic Doppler Velocimeter in 1993, our product line has grown into a diverse, multi-faceted mix of high technology instruments designed for a wide variety of applications. Put simply, our instruments tell you how fast the water is moving, where it is moving, and even if it is not moving at all. On top of that, just about all our products are offered with an array of ancillary sensors for complete environmental monitoring solutions.

Sold worldwide, our innovative instrumentation is designed on the basis of your requirements to fit the proper environment, measurement criteria, and budget. Our products could be as easily found in a university laboratory as they could in the deep ocean, along the coast, or in a river, lake, or stream. From the depths of the Pacific Ocean, to the Amazon River, to the small creek in your backyard, there are SonTek/YSI instruments hard at work everyday.

And keeping it easy to use is part of what SonTek/YSI is all about. Industry-leading software packages tailored for your application help give you the confidence you need. Be it for directional wave analysis, river discharge calculation, or flow monitoring, SonTek/YSI has a complete solution.

A strong commitment to customer service is a cornerstone of our philosophy. When you call SonTek/YSI, you have the expertise you need at your disposal. Our professional staff includes experts in fluid dynamics, oceanography, hydrology, and all the engineering disciplines. We are happy to have this opportunity to show you who we are, and we look forward to helping you with your application.

We truly are "The World Leader for Water Velocity Measurement".