I2EM scientific component

Original scientific implementation: Adrian Fung, IEEE-GRSS Remote Sensing
Code Library, DOI 10.21982/M8BC7Z (2016).
Book: Fawwaz T. Ulaby and David G. Long, Microwave Radar and Radiometric
Remote Sensing (2014), section 10-3.9.

The RSPhysics maintainer has confirmed authorization to publicly distribute
the adapted implementation. This authorization is specific to this project;
it does not relicense the original MATLAB program under Apache-2.0 or imply
a general redistribution grant for that original program. Original source
is obtained separately from IEEE-GRSS and is not included in this package.

RSPhysics-authored interface, validation, and packaging code is Apache-2.0.
For questions about the scientific component's permissions, contact the
RSPhysics maintainer: https://github.com/jianboqi/RSPhysics/issues
