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Portals have become very popular on the internet. They allow users to access many online transactions and customized information. More recently, semantic portals emerged as a natural extension of traditional portals and they have been attracting researchers and enterprise attention as a new way to provide information. This paper covers these issues and shows how ontologies can improve results relevance in one of the most important component of a portal: the search mechanism. It describes a search tool developed in the context of a semantic portal named PASS (Portal with Access to Semantic Search). This tool uses components of domain ontologies stored in the portal to expand terms during the search process.

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In this work CdS/CdTe solar cells were submitted to solution, sublimation and vapor CdCI2 treatments, followed by NP etch for several periods of time. The influence of these procedures on cell efficiency is discussed.The individual layers are analyzed and the results are compared with similar studies in the literature. The best NP etching time was 20 s for all CdCI2 treatments. The highest efficiency was achieved for the cell submitted to the solution treatment at 380°C. Although the layers have shown good properties for a high efficiency cell, the maximum overall efficiency was only 7.8%, probably due to high series and low shunt resistances.