Joachim Hammer

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The goal of the Tsimmis Project is to develop tools that facilitate the rapid integration of heterogeneous information sources that may include both structured and unstructured data This paper gives an overview of the project describ ing components that extract properties from unstructured objects that translate information into a common object model that(More)
A warehouse is a repository of integrated information drawn from remote data sources. Since a warehouse effectively implements materialized views, we must maintain the views as the data sources are updated. This view maintenance problem differs from the traditional one in that the view definition and the base data are now decoupled. We show that this(More)
The goal of the Tsimmis Project is to de velop tools that facilitate the rapid integra tion of heterogeneous information sources that may include both structured and unstructured data This paper gives an overview of the project describing components that extract properties from unstructured objects that translate information into a common object model that(More)
In order to access information from a variety of heterogeneous information sources, one has to be able to translate queries and data from one data model into another. This functionality is provided by so-called (source) <italic>wrappers</italic> [4,8] which convert queries into one or more commands/queries understandable by the underlying source and(More)
We introduce our new, publicly available testbed and benchmark called THALIA (Test Harness for the Assessment of Legacy information Integration Approaches) for testing and evaluating integration technologies. THALIA provides researchers with a collection of 40 downloadable data sources representing University course catalogs from computer science(More)
This paper describes the design and implementation of a replicable, Internet-based negotiation server for conducting bargaining-type negotiations between enterprises involved in e-commerce and e-business. Enterprises can be buyers and sellers of products/services or participants of a complex supply chain engaged in purchasing, planning, and scheduling.(More)
The TSIMMIS project [I] provides an architecture and tools for accessing multiple heterogeneous information sources by translating source information into a common self-describing object model, called the Object Exchange Model (OEM) [2]. TSIMMIS provides integrated access to heterogeneous sources through a layer of source specific translators as well as(More)