Davies L, Chappell P, Melvin T
Institute of Complex Systems and Simulation, University of Southampton, Southampton, UK.
Electronics and Computer Science, University of Southampton, Southampton, UK.
Skin Res Technol. 2017 Aug;23(3):363-368. doi: 10.1111/srt.12344. Epub 2016 Nov 22.
Electrical signals are recorded from and sent into the body via the skin in a number of applications. In practice, skin is often hydrated with liquids having different conductivities so a model was produced in order to determine the relationship between skin impedance and conductivity.
A model representing the skin was subjected to a variety of electrical signals. The parts of the model representing the stratum corneum were given different conductivities to represent different levels of hydration.
The overall impedance and conductivity of the cells did not vary at frequencies below 40 kHz. Above 40 kHz, levels of increased conductivity caused the overall impedance to decrease.
The variation in impedance with conductivity between 5 and 50 mSm can be modelled quadratically while variation in impedance with conductivity between 5 and 5000 mSm can be modelled with a double exponential decay.
在许多应用中，电信号通过皮肤记录并传入人体。在实际操作中，皮肤常被具有不同电导率的液体浸湿，因此建立了一个模型来确定皮肤阻抗与电导率之间的关系。
对一个代表皮肤的模型施加各种电信号。代表角质层的模型部分被赋予不同的电导率以代表不同的水合水平。
在低于40kHz的频率下，细胞的总阻抗和电导率没有变化。高于40kHz时，电导率的增加导致总阻抗降低。
5至50mS/m之间的阻抗随电导率的变化可以用二次函数建模，而5至5000mS/m之间的阻抗随电导率的变化可以用双指数衰减建模。
