This paper gives a method to measure the conductivity base on choosing frequency. After adding to the electrode with two AC square waves of appropriate frequencies,we can measure the output DC voltage of the circuit.
本论文提出了一种选频电导率测量方法，选择两个合适频率的交流方波施加于电极，测出电路输出直流电压，通过解方程组求出时间常数，然后求得溶液电阻，进而得到溶液电导率。
参考来源 - 溶液电导率测量方法的研究·2,447,543篇论文数据，部分数据来源于NoteExpress
Then this text is to analyze and recommend the key technology of Bluetooth system ( choosing frequency band , address code , rate;
然后，分析介绍了蓝牙无线系统的关键技术（选择频段、地址码、速率；
The paper also introduces the evolution of control mode in frequency transducer, and demonstrated the principles of choosing frequency transducer in air conditioning projects through a case study.
述及变频器控制方式的演进，并通过实例说明在暖通空调工程中变频器的选用原则。
These conclusions are important for choosing suitable radar system parameters such as center frequency , resolution and imaging squint angle in engineering design.
这些结论对工程设计牛选择合适的工作参数，如载频、分辨率、成像斜角等具有较为重要的参考价值。
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