To provide a sensor element improved in accuracy and reliability for surface monitoring such as detection of water, snow and ice on the exposed surface, and detection of ice formation in an initial stage, and a method of detecting a capacity change of the sensor element.
This method/system includes a multi-frequency generator 110 for supplying signals of at least three different frequencies to an electrode assembly, and detects capacities of the electrode assembly 130 as to a plurality of different frequency points. The capacity of the electrode assembly 130 affected by a substance in the vicinity of the electrode assembly 130 is surely discriminated by this manner. Preferably, a condition of a road surface is able to be accurately monitored.
RICCARDI MARCO
MEINDL TASSILO B
| JPS62249048A | 1987-10-30 | |||
| JP2003078365A | 2003-03-14 | |||
| JPH05297039A | 1993-11-12 | |||
| JPH0443284U | 1992-04-13 | |||
| JP2001249028A | 2001-09-14 | |||
| JPH075135A | 1995-01-10 | |||
| JP2002196085A | 2002-07-10 | |||
| JPH05507561A | 1993-10-28 |
Next Patent: NMR MEASURING METHOD AND NMR PULSE SEQUENCE