variavel0=<b>Ernani Vitillo Volpe</b> - ernani.volpe@poli.usp.br Escola Politécnica da USP
<b>Abstract.</b> Since its inception, the maximum entropy method has been perceived as a  potential tool for investigating the near-equilibrium region in kinetic  theory of gases, thus providing an alternative to the more traditional  small disturbance expansions, such as Chapman-Enskog and Grad`s method.  However, it became clear early on that one would have to overcome some  major mathematical difficulties, before that goal could be attained. Chief  among these difficulties is the so-called moment problem, which consists of  solving for the probability density function (pdf) parameters in terms  of its moments. Although it can be solved by means of numerical methods,  the application outlined above requires an analytical solution.   This work presents a method for obtaining an analytic small disturbance solution to the moment problem associated with maximum entropy pdfs. This method allows one to express pdf parameters in terms of constrained moments, alone. The  results thus obtained hold for pdfs that represent small perturbations from  a known pdf within this class. Since the Maxwellian is itself a maximum  entropy pdf, the method effectively opens up the possibility of using this class of pdfs to investigate the near-equilibrium region.
<b>Keywords.</b> moment problem, pdf methods, maximum entropy, small disturbance expansion.