4 papers
math.FA2007
Trace ideals for pseudo-differential operators and their commutators with symbols in -modulation spaces
Masaharu Kobayashi, Mitsuru Sugimoto, Naohito Tomita
In this paper, we consider the trace property of pseudo-differential operators with symbols in -modulation spaces.
math.FA2007
A remark on fractional integrals on modulation spaces
Mitsuru Sugimoto, Naohito Tomita
In this paper, we give the necessary and sufficient conditions for the boundedness of fractional integral operators on the modulation spaces.
math.FA2007
A counterexample for boundedness of pseudo-differential operators on modulation spaces
Mitsuru Sugimoto, Naohito Tomita
We prove that pseudo-differential operators with symbols in the class () are not always bounded on the modulation space ().
math.AP2006
Smoothing estimates for evolution equations via canonical transforms and comparison
Michael Ruzhansky, Mitsuru Sugimoto
The paper describes a new approach to global smoothing problems for dispersive and non-dispersive evolution equations based on the global canonical transforms and the underlying gl…