Abstract: An image information file and retrieving apparatus and method wherein information of an image of at least one document having text information and non-text information is inputted and stored together with attribute information of a relationship of at least one of the text information and the non-text information of the at least one document. The stored image information is retrieved in accordance with a retrieval condition indicating a requested relationship between the text information and non-text information. More particularly, a fuzzy weighting function is utilized for retrieval.

Abstract: In a process for continuously producing polyester which comprises continuously polymerizing bis-.beta.-hydroxyethyl terephthalate and/or a lower polymer thereof using a plurality of vacuum polymerization reactors equipped with a stirrer disposed in series, the improvement which comprises automatically and continuously measuring stirring power or stirring axis reaction force of at least the final polymerization reactor among the polymerization reactors from which a polymer having a limiting viscosity (.eta.) of 0.25 or more is removed, and controlling the vacuum in the polymerization reactors based on changes in the stirring power or reaction force so that the stirring power or reaction force is kept at a prescribed level, by which the degree of polymerization of the polymer removed from the polymerization reactors is controlled. A process for producing a polyester spun fiber is also disclosed.