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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.

Currently managing information overload has become a major challenge. How to manage all these data, presented in diverse formats and originating from heterogeneous sources? This paper presents a strategy to perform data fusion effectively. Our strategy deals with the problem of object identification in the context of the Command and Control of the Brazilian Defense Ministry using MIP 1 Data Model from NATO 2 , also known as JC3IEDM 3 . For that, data duplication strategies will be used, as well as clustering, search and information retrieval techniques to study similarity, such as TF-IDF and Thesauri.

Abstract. Traditional workflow systems don't handle dynamic scenarios well, as they are centralized and pre-defined at the start of the project. In this paper, we present a P2P framework to support dynamic workflows, which uses contracts to deal with unexpected changes in the flow of activities. DynaFlow is an agent based framework, where agents take action when exceptions occur. DynaFlow could provide adequate support for E-Science experiments mapped into workflows instances, with tasks operating in distributed environments and diverse types of computational resources and data.

Abstract-This paper aims to present a computational framework capable of withstanding the effects produced by transient overloads on physical and virtual servers hosted on cloud computing environment. The proposed framework aims at automating management of virtual machines that are hosted in this environment, combining a proactive strategy, which performs load balancing when there is not overload of physical and/or virtual machines with a reactive strategy, which is triggered in the event of overload in these machines. On both strategies, it is observed the service level agreement (SLA) established for each hosted service according to the infrastructure as a service (IaaS) model. The main contribution of this paper is the implementation of a computational framework called Phoenix, capable of handling momentary overloads, considering the CPU, memory and network resources of physical and virtual machines and guaranteeing SLAs. The results demonstrate that Phoenix framework is effective, and it has outstanding performance in handling overloads virtual machine network, which has achieved the isolation of momentary overload on the physical machine preventing the propagation of their effects on the cloud.