具有一定混合光滑模的Besov型函数空间的函数表现定理

REPRESENTATION THEOREM FOR FUNCTIONS OF A BESOV TYPE SPACE OF FUNCTIONS WITH A GIVEN MIXED MODULOUS OF SMOOTHNESS

在多元周期的Ｌ_ｐ（１＜ｐ＜∞）空间内引入一类具有一定混合光滑模的线性子空间，在此空间上定义了Ｂｅｓｏｖ型半范数，并且建立了Ｎｉｋｏｌｓｋｉｉ－Ｌｉｚｏｒｋｉｎ型的函数表现定理．

In the space L_p(1 <p<∞) of multivariate periodic functions a subspace of functions with a given mixed modulous of smoothness is introduced.In this space a Beov- type semi-norm is defined,and a representation theorem of Nikolskii -Lizorkin type is proved.