KNOWLEDGE REPRESENTATION APPROACH TO CLOSED LOOP CONTROL SYSTEM - A TANK SYSTEM CASE-STUDY

Control engineering problems are dealt within a plethora of methods and approaches depending on the a priori knowledge, the description of the process to control, and the main control goal. Classical control theory is mainly based on properties of numerical models. This paper presents an approach that applies to a class of processes described by numerical and logical relations using inference and a knowledge base system. To attain this goal an ontology for control systems is constructed. The work presented in this paper is based in a three tank system benchmark

Ontology based Clinical Practice Justification in Natural Language

One of the most important contributions that any decision support system can make to achieve wide acceptance among any community is to be able to justify its own suggestions. When dealing with highly technical and scientifically advanced practitioners like medical doctors or any other related clinical workers, the ability to justify itself using the domain specialist usual terminology and technicalities is imperative. In this article we demonstrate the use of an ontological framework as inferencing basis for automatic sound clinical suggestions providing. Our work has two main contributions, consolidating the use of \{OGCP\} (Ontology for General Clinical Practice) as foundation and providing controlled English justifications of the extracted suggestions. We found that clinical practitioners feel as acceptable the Attempto Controlled English justifications generated from the knowledge base

A Review on Cooperative Question-Answering Systems

The Question-Answering (QA) systems fall in the study area of Information Retrieval (IR) and Natural Language Processing (NLP). Given a set of documents, a QA system tries to obtain the correct answer to the questions posed in Natural Language (NL). Normally, the QA systems comprise three main components: question classification, information retrieval and answer extraction. Question classification plays a major role in QA systems since it classifies questions according to the type in their entities. The techniques of information retrieval are used to obtain and to extract relevant answers in the knowledge domain. Finally, the answer extraction component is an emerging topic in the QA systems. This module basically classifies and validates the candidate answers. In this paper we present an overview of the QA systems, focusing on mature work that is related to cooperative systems and that has got as knowledge domain the Semantic Web (SW). Moreover, we also present our proposal of a cooperative QA for the SW

Using a dialogue manager to improve search in the semantic web

Question-Answering systems that resort to the Semantic Web as a knowledge base can go well beyond the usual matching words in documents and, preferably, find a precise answer, without requiring user help to interpret the documents returned. In this paper, we introduce a Dialogue Manager that by analysing the question and the type of expected answer, provides accurate answers to questions posed in Natural Language. The Dialogue Manager not only represents the semantics of the questions, but also the structure of the discourse including the user intentions and the questions context, adding the ability to deal with multiple answers and providing justified answers. Our system performance is evaluated by comparing with similar question answering systems. Although the test suite has slight dimensions, the results obtained are very promising

A strategy for archives metadata representation on CIDOC-CRM and knowledge discovery

This paper presents a strategy for the semantic migration of Portuguese National Archives records into CIDOC-CRM standard, an ontology developed for museums, within the context of the EPISA project. The approach to automatically populate the CIDOC-CRM is based on Mapping Description Rules to semantically translate the archives descriptive information into CIDOC-CRM representation. The compliance of the CIDOC-CRM model recommendations guarantees that the populated CIDOC-CRM ontology of archives descriptive information verifies interoperability, and could be linked and integrated with other populated CIDOC-CRM ontologies. In the information modelling, requirements on the mapping representation, due to the intent of interpreting natural language text to automatically extract information of metadata text fields and to interpret natural language queries, are taken into account. To automatically interpret the Mapping Description Rules, OWL API was used to obtain the set of assertions that represents the information in the target ontology and two datasets are available with some migration examples. The exploration of the knowledge representation is done through some Description Logic queries to highlight the advantages of having this new representation of the National Archives. The evaluation of the resulting representation can be done automatically proving its correctness for the metadata that has a direct representation in CIDOC-CRM

A Tool to Explore the Population of a CIDOC-CRM Ontology

This paper presents a visualising tool to explore the population of an Ontology, obtained through the processes of automatic migration and text information extraction. It was developed in the context of EPISA project, a R&D project that aims to represent the Portuguese National Archives records information in CIDOC-CRM, an ontology developed for museums. The tool allows the migration process developers to visualise the instances and their properties, and to debug the migration process and the migration representation model, or to explore the Archives by final users. It uses modeling and reasoners OWL-API with SPARQL-DL queries to obtain the exploration results

Processamento de texto: Interpretacao temporal

In this thesis I propose and characterize a general theory for the pragmatic interpretation of the temporal entities in a text. This theory enables the construction of a knowledge base containing the temporal information conveyed by the text, together with the text's temporal structure. According to the theory proposed here in, the pragmetic interpretation of the temporal entities is performed incrementally, one sentence at a time, in each sentence's context. I also describe and analyze an implemented system based on the proposed theory. The most relevant and origin contributions of this thesis are: - The language for the semantic representation of the sentences of a text. This language has a temporal ontology with concepts that are close to those used in natural language, hence simplifying the reasoning necessary for the interpretation of temporal entities. It has a well-defined, non-monotonic semantics, allowing to ascertain whether the representation of s et of sentences is consistent or not. - The text temporal structure. The proposed structure is clearly formalized and the algorithms for its construction are well defined. The criterion for grouping sentences in this structure, relies exclusively on the determination of the temporal relations among the eventualities times of the text sentences. The structure is built incrementally, one sentence at a time, as a result of the interpretation of the temporal entities. This structure allows us to define the discourse entities most relevant for the interpretation of each text sentence. This structure imposes temporal constraints on the times of the events or states mentioned in the sentences. This constraints are due to its underlying formalization. Thus, the text's temporal structure is an active component in the interpretation of sentence's temporal entities, as it may reject some interpretations and will lead to more cohesive interpretations (i.e. those where there are more relations between text entities)Available from Fundacao para a Ciencia e a Tecnologia, Servico de Informacao e Documentacao, Av. D. Carlos I, 126, 1200 Lisboa / FCT - Fundação para o Ciência e a TecnologiaSIGLEPTPortuga

A Logic Programming Based Approach to QA@CLEF05 Track

In this paper the methodology followed to build a question- answering system for the Portuguese language is described. The system modules are built using computational linguistic tools such as: a Por- tuguese parser based on constraint grammars for the syntactic analysis of the documents sentences and the user questions; a semantic interpreter that rewrites sentences syntactic analysis into discourse representation structures in order to obtain the corpus documents and user questions semantic representation; and finally, a semantic/pragmatic interpreter in order to obtain a knowledge base with facts extracted from the docu- ments using ontologies (general and domain specific) and logic inference. This article includes the system evaluation under the CLEF’05 question and answering track

A question-answering system for Portuguese juridical documents

We present a Question-Answering (QA) system for Por- tuguese juridical documents. The QA system was applied to the complete set of deci- sions from several Portuguese juridical institutions (Supreme Courts, High Court, Courts, and Attorney-General’s Office) in a total of 180,000 documents

The BRIDG model as the most authoritative resource in Shared Semantics for Ontologies development in Healthcare practice

Developing a meaning service like a suitable ontology is of paramount importance to achieve Computing Semantic Interoperability (CSI) in every eld. In Healthcare, every system involved must agree in the meaning of a clinical concept. This is the fundamental concept of Shared Semantics that has to be realized to obtain CSI in the Health sub-domain of knowledge. We present the HL7 RIM inadequacy for ontology mapping and how to cir- cumvent it using the BRIDG DAM. Natural Language Processing techniques for automated ontology population are discussed and the current trends about knowledge representation and reasoning in the Healthcare domain are pre- sente