| dc.description.abstract | Information systems and other computer-based systems must continuously undergo change in order to reflect change in their environments. The present technology used to implement such systems, including models, methods, tools and languages, does not have an inherent understanding of the nature of evolution. The rigidity of existing systems is a hindrance for user requested enhancements.Propagating changes correctly is a particular problem. It is common to find that necessary changes consequent on some other change have not been made, so that the system is inconsistent and will eventually fail to operate correctly. The paper discusses tools for system maintenance and focuses on the issue of automation. A tool that automatically generates and maintains all the information it needs is presented. To provide more information about the form and extent of the evolution in real-world systems, the same tool was instructed to collect change measurements. Information about the evolution of a large health management system was recorded over a period of 18 months. Methods for and problems of automatic change measurements collection are discussed. | eng |