You might well see something interesting - the output will contain signals derived from movement of various body organs which change the impedance of the body. Look up "impedance plethysmography" and "electro-laryngograph" for examples of instruments that use this effect. However, the signal changes are generally very small modulations that can be difficult to extract.
John
Imagine that. The "technologist" errs.
You're not a scientist. You're a dopey little bastard scientist wanna be.
Pages 615 and 616. Sheesh back at'cha.
Fig 4 is sort of the config the op is referring to. I think.
A human body is, after all, a bag full of salty water. Conduction is ionic, so it doesn't behave like a pure resistor.
John
snipped long line.
LIKE "a bag full of salty water".
Blood, conducts quite well with salt being the main reason, but there are other compounds involved as well, so I don't know if calling blood 'ionic' is too correct.
The 'diagram' your citation shows looks largely resistive to me.
There were a LOT of resistors, in fact.
I'd venture to say that the little RC models are mainly for and including the skin.
Human skin is HUGELY variable. Just ask any polygraphists.
We are mostly resistive. Pretty simple shit.
Would you believe that sounds like a process I've read about being used for determining state of charge of lead acid batteries? You get back a fingerprint of the internal impedance. No tape of course, but feeding a complex pseudo random waveform (lots of frequencies together) can show up the changes you may be looking for. Use a repeatable noise sequence for the tests.
Interpretation is something else though. That's the magical bit, making sense of the 'noise'. Lots of work to correlate the trials to show you are finding something useful. I don't have a clue where to go for that, sounds more like computation than measurement.
Grant.
It's sure not metallic conduction, unless you're RoboCop.
John
It sure isn't capacitively or inductively reactive either.
Like lightning, when a salt has a conduction chain (path) set up 'in' it, it conducts better, a bit akin to plasma.
That is why a lightning strike will use a particular 'vein' down a tree to Earth, as opposed to the entire the trunk mass, even though the "conductivity" of any given part of the trunk was pretty even. Baked tree conducts better then fresh tree. So the entire stroke follows one path through the tree.
The word for today is "caramelized".
Bwuahahahahahaha!
Tasty in word salad.
John
I did something similar for my diploma thesis. However, I was not using white noise, but a frequency sweep from 10 kHz to 1 MHz. This made the equipment much easier (DDS generator, voltage controlled current source, I/Q demodulator and slow ADC). The method is called bioimpedance spectroscopy and you will find some information about it on the net. There is also a commercially available device for it, made by Xitron.
You will get Cole-Cole diagrams. It is essential to measure the complex impedance instead of the resistive component only. You can then make a curve fit to determine the parameters of your mathmatical model.
Depends on what you are hoping to get...
The medical safety norm EN-60601. IIRC, it says I < 1 mA for f < 10 kHz, I < 10 mA for f < 1 MHz.
I don't think we need another method of determining people's identity.
Perhaps you could turn your thoughts towards something more medically beneficial?
RL
It was 35 years ago, idiot.
Coming from you, this further proves that your brain has a self imposed retardation mindset.
They take you down directly in the blood now, by placing the chilling rod right in your artery. Within minutes, the body temp can be brought down to 34°F. The machine I made was used for decades and they were all made right here in the US. They cool the body by way of blankets with the chill water running through them, and the machine chilled the water, and would heat it back up after the operation.
Williams, you are an idiot. That has been true, every time I ever said it about you, and it is usually after you make a fool of yourself with stupid posts like the above. Wallow in it, boy.
Are you so retarded that you do not know how to google something?
Fuck off. Your stupid, incorrect reference will no longer be addressed.
Right. You're a janitor, now.
AlwaysWrong is always wrong.
You're already below room temperature, DimBulb. You were born that way.
Everyone here knows you're wrong, AlwaysWrong. Always.
It's about time you left, AlwaysWrong!
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