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Based in internet growth, through semantic web, together with communication speed improvement and fast development of storage device sizes, data and information volume rises considerably every day. Because of this, in the last few years there has been a growing interest in structures for formal representation with suitable characteristics, such as the possibility to organize data and information, as well as the reuse of its contents aimed for the generation of new knowledge. Controlled Vocabulary, specifically Ontologies, present themselves in the lead as one of such structures of representation with high potential. Not only allow for data representation, as well as the reuse of such data for knowledge extraction, coupled with its subsequent storage through not so complex formalisms. However, for the purpose of assuring that onto...
In this work we present a system for information extraction from Learning Management Systems. This system is ontology-based. It retrieves information according to the structure of the ontology to populate the ontology. We graphically present statistics about the ontology data. These statistics present latent knowledge which is difficult to see in the traditional Learning Management System. To answer questions about the ontology, a question answering system was developed using Natural Language Processing in the conversion of the natural language question into an ontology query language; Sumário: Extração de Informação de Sistemas de Gestão para Educação Usando Ontologias Neste dissertação apresentamos um sistema de extracção de informação de sistemas de gestão para educação (Learning Management Systems). Este sistema é baseado em o...
Some of the existing techniques for soil decontamination are reviewed, giving particularemphasis to supercritical extraction (SCE), an environmental friendly technique whose applications to thetreatment of effluents and soil remediation are only emerging now. The experimental apparatus andanalytical technique used in our laboratory to study the extraction of atrazine from contaminated soil bySCE with carbon dioxide is described.
This presentation will focus on some techniques for the extraction of bilingual resources for machine translation, giving some emphasis to the extraction of translation examples. It will include a brief experiment on the usage of these resources for hybrid machine translation.
Dissertação de mestrado, Engenharia Eléctrica e Electrónica, Instituto Superior de Engenharia, Universidade do Algarve, 2016
The ability to recognize when digital content is becoming endangered is essential for maintaining the long-term, continuous and authentic access to digital assets. To achieve this ability, knowledge about aspects of the world that might hinder the preservation of content is needed. However, the processes of gathering, managing and reasoning on knowledge can become manually infeasible when the volume and heterogeneity of content increases, multiplying the aspects to monitor. Automation of these processes is possible [11,21], but its usefulness is limited by the data it is able to gather. Up to now, automatic digital preservation processes have been restricted to knowledge expressed in a machine understandable language, ignoring a plethora of data expressed in natural language, such as the DPC Technology Watch Reports, which could gr...
The goal of this study was to compare the extraction of rosmarinic acid from Melissa officinalis L. using three techniques (heat- -, microwave- and ultrasound- assisted extraction). In order to obtain the conditions that maximize the rosmarinic acid extraction, a response surface methodology was applied using the circumscribed central composite design of three variables with five levels. The relevant independent variables used for the process optimization were time, temperature and ethanol–water proportion for heat-assisted- and microwave-extration, whereas for the ultrasound method the ultrasonic power was variable. The responses used as criteria were the amount of rosmarinic acid was determined by HPLC-DADand the extraction yield of the obtained residue. Ultrasound extraction proved to be the most effective method, capable of yieldin...
A stir bar sorptive extraction with liquid desorption followed by large volume injection coupled to gas chromatography–quadrupole mass spectrometry (SBSE-LD/LVI-GC–qMS) was evaluated for the simultaneous determination of higher alcohol acetates (HAA), isoamyl esters (IsoE) and ethyl esters (EE) of fatty acids. The method performance was assessed and compared with other solventless technique, the solid-phase microextraction (SPME) in headspace mode (HS). For both techniques, influential experimental parameters were optimised to provide sensitive and robust methods. The SBSE-LD/LVI methodology was previously optimised in terms of extraction time, influence of ethanol in the matrix, liquid desorption (LD) conditions and instrumental settings. Higher extraction efficiency was obtained using 60 min of extraction time, 10% ethanol content, n...
Important sources of information are originally created in natural language. To make that knowledge computer processable it is necessary to understand the structure of natural languages, by adding lexical and syntactic information; to have a rich representation to encode the knowledge of sentences, like ontologies; and to develop algorithms to bridge the gap between natural languages and computer processable representations. In this paper we present the architecture, modules and results of a prototype that uses an ontology to represent the world concepts and their relationships, and also to guide the process of extracting information from natural language documents. The system was tested using minutes of Portuguese municipalities’ meetings. Initial results are presented for three topics of municipalities' affairs: the subsidies granted,...
A very relevant problem in e-government is that a great amount of knowledge is in natural language unstructured documents. If that knowledge was stored using a computer-processable representation it would be more easily accessed. In this paper we present the architecture, modules and initial results of a prototype under development for extracting information from government documents. The prototype stores the information using a formal representation of the set of concepts and the relationships between those concepts - an ontology. The system was tested using minutes of Portuguese Municipal Boards meetings. Initial results are presented for an important and frequent topic of the minutes: the subsidies granted by municipalities.
Central libraryPalácio Ceia
Rua da Escola Politécnica, nº 141 - 147
1269-001 Lisboa, Portugal

Phones: (+351) 300 002 922
(+351) 300 002 925 | (+351) 300 002 930
(+351) 300 002 931 | (+351) 300 002 932
Electronic mail: cdoc@uab.pt

Opening hours:
Monday to friday, 9h to 18h
Coimbra delegationRua Alexandre Herculano, nº 52
3000-019 Coimbra, Portugal

Phone: (+351) 300 001 590
Electronic mail: cdocoimbra@uab.pt

Opening hours:
Monday to friday, 9h to 12h30 and 14h às 18h
Porto delegationRua de Amial, nº 752
4200-055 Porto, Portugal

Phone: (+351) 300 001 700
Electronic mail: cdocporto@uab.pt

Opening hours:
Monday to friday, 9h to 17h30