What's the difference between a thermal resistor and thermocouple principle?

What's the difference between a thermal resistor and thermocouple principle? If the concentration of electrons and holes respectively n, p, mobility of u n, u p, respectively, the conductivity of the semiconductor is: sigma = q ( nμn+pμp） Because of n, p, u n, u p is a function of T depend on temperature, so the conductance is a function of temperature, so can be calculated by measuring conductivity of high and low temperature, and can make the resistance -

two different ingredients of conductor ( Called the thermocouple wire or hot electrode) Two ends synthesis loop, when the junction temperature is not at the same time, in the circuit will generate electromotive force, this kind of phenomenon called the thermoelectric effect, and the electromotive force called thermoelectric potential. Thermocouple is to use the principle of temperature measurement, which is directly used as a measure of medium temperature is called the work at the end of the end, the other end is called the cold end; The cold end connected to the display instrument or meter, display instrument will point out of thermocouple thermoelectric number.