  This work takes part of the development of far-infrared and millimeter
astrophysics. We have worked on the data processing and analysis in the fields
of the Galactic interstellar medium, through the dust thermal emission, and
cosmology through the observation of the cosmic microwave background
fluctuations. We have been particularly interested in optimal map-making by
inverse linear methods. We have developed a new map-making method for the
balloon-borne submillimeter experiment PRONAOS, based on a Wiener inversion
matrix, which allows to globally reconstruct the map. The analysis of PRONAOS
maps in massive star-forming complexes as Orion and M17 allowed us to discover
the large variations of the physical conditions and the dust properties. We
showed an anticorrelation between the temperature and the submillimeter
spectral index. Our investigations concerning this effect favour causes related
to the intrinsic physics of the grains. We have also developed optimal
map-making methods for the experiments aiming at measuring the cosmic microwave
background fluctuations. The iterative methods that we have developed allow to
reconstruct the sky maps very accurately, in spite of the large amount of
self-correlated noise present in the timelines. We have also worked on the data
processing and analysis for the Archeops balloon-borne experiment.
