Patent Document ID: 20090319157
Application ID: 12486038
Patent Flag: 0

Claim One:
1. A learning device that has a storing means for storing a model formula expressing a detected waveform with a mathematical expression, the detected waveform being detected with a sensor that detects a physical quantity change, and that learns values of multiple parameters included in the model formula to improve an approximation degree of the model waveform expressed with the model formula with respect to the actual detected waveform, the learning device comprising: a parameter changing means for changing each of the multiple parameters to an increased side and to a decreased side with respect to a reference value set for each of the multiple parameters; an approximation degree calculating means for calculating the approximation degree for each combination of the changes of the multiple parameters; a determining means for determining whether an update end condition is satisfied, the update end condition being a condition that the approximation degree in the case where the multiple parameters are set at the reference values is higher than any of the approximation degrees in the case where the parameters are set at the changed values; a reference value updating means for updating the reference values by using the combination of the changes, which provides the highest approximation degree among the approximation degrees corresponding to the changed values, as the updated reference values while the update end condition is not satisfied; and a learning value deciding means for deciding the reference values as learning values of the multiple parameters when the update end condition is satisfied, wherein the change by the parameter changing means, the calculation by the approximation degree calculating means and the determination by the determining means are repeatedly performed every time the update is performed by the reference value updating means.