In certain applications where temperature changes rapidly, e.g., compressor cylinder or explosion chamber, it is necessary to obtain data with a sample rate high enough register the change, i.e., probe response time must be very low. Type E coaxial thermocouples in range of µs can an example such probe. This paper describes several approaches for high-frequency obtained using thermocouples. Ind...

We consider the problem of unique identification of dielectric coefficients for gratings and sound speeds for wave guides from scattering data. We prove that the “propagating modes” given for all frequencies uniquely determine these coefficients. The gratings may contain conductors as well as dielectrics and the boundaries of the conductors are also determined by the propagating modes.