A sand sample collected at the foot of Flaming Mountain was studied further. On the basis of the change in the relative intensity after heat treatment, one of the sextets observed in its Mossbauer spectrum at liquid n...A sand sample collected at the foot of Flaming Mountain was studied further. On the basis of the change in the relative intensity after heat treatment, one of the sextets observed in its Mossbauer spectrum at liquid nitrogen temperature was ascribed to goethite. This result provides a useful information on the geological history of the region where the mountain is located.展开更多
We generalize a theorem of Ky Fan about the nearest distance between a closed convex set D in a Banach space E and its image by a function f:D→E,in several directions:(1)for noncompact sets D.when f(D)precompact:(2)f...We generalize a theorem of Ky Fan about the nearest distance between a closed convex set D in a Banach space E and its image by a function f:D→E,in several directions:(1)for noncompact sets D.when f(D)precompact:(2)for compact D and upper semicontinuous multifunction f:and more generally,(3)for noncompact D and upper semicontinuous multifunction f with f(D)Hausdorff precompact. In particular,we prove a version of the fixed point theorem of Kakutani-Ky Fan for multifunctions. whose values are convex closed bounded,thus not necessarily compact.展开更多
文摘A sand sample collected at the foot of Flaming Mountain was studied further. On the basis of the change in the relative intensity after heat treatment, one of the sextets observed in its Mossbauer spectrum at liquid nitrogen temperature was ascribed to goethite. This result provides a useful information on the geological history of the region where the mountain is located.
基金partially supported by the project"Geometrical functional analysis in Banach spaces:variational principles and global approximation"between Italy and Bulgaria
文摘We generalize a theorem of Ky Fan about the nearest distance between a closed convex set D in a Banach space E and its image by a function f:D→E,in several directions:(1)for noncompact sets D.when f(D)precompact:(2)for compact D and upper semicontinuous multifunction f:and more generally,(3)for noncompact D and upper semicontinuous multifunction f with f(D)Hausdorff precompact. In particular,we prove a version of the fixed point theorem of Kakutani-Ky Fan for multifunctions. whose values are convex closed bounded,thus not necessarily compact.
