Showing all 44 Tech Reports linked to Enrico Motta
Describing semantic web applications through relations between data nodes
Semantic Web Applications can only be understood if the complex data flows they implement are clearly described. However, application developers have very little support at the moment for documenting such data flows and their rationale, in an appropriately formal and conceptual manner. In this paper, we propose to apply a knowledge engineering approach to the formal description of Semantic Web Applications. Following an ontology building methodology based on the analysis of several existing...read more
Unsupervised data linking using a genetic algorithm
As commonly accepted identifiers for data instances in semantic datasets (such as ISBN codes or DOI identifiers) are often not available, discovering links between overlapping datasets on the Web is generally realised through the use of fuzzy similarity measures. Configuring such measures, i.e. deciding which similarity function to apply to which data properties with which parameters, is often a non-trivial task that depends on the domain, ontological schemas, and formatting conventions in...read more
Probabilistic Methods for Data Integration in a Multi-Agent Query Answering System
This report describes the progress that has been achieved during the second year (full time equivalent 1 July 2006 - 1 July 2008) of our Ph.D. research. All the work has been built upon the achievements of the first year and confirmed that the original research objectives were correctly identified at the beginning of the research. We have successfully participated in the Ontology Mapping Evaluation Initiative 2006 and 2007 (2008 ongoing activity), which provided a qualitative...read more
State of the art on Semantic Question Answering
We analyze the contributions, challenges and dimensions of question answering on the Semantic Web by looking at the state of the art on semantic question answering systems, and the implications in traditional methods on ontology selection, mapping and semantic similarity measures to balance the heterogeneity and large scale semantic data with run time performanceread more
ID: kmi-07-03
Date: 2007
Author(s): Vanessa Lopez, Enrico Motta, Victoria Uren, Marta Sabou
Resources:
The Open University at TREC 2006 Enterprise Track Expert Search Task
The Multimedia and Information Systems group at the Knowledge Media Institute of the Open University par-ticipated in the Expert Search task of the Enterprise Track in TREC 2006. We have proposed to address three main innovative points in a two-stage language model, which consists of a document relevance model and a co-occurrence model, in order to improve the performance of expert search. The three innovative points are based on characteristics of documents. First, document authority in terms...read more
ID: kmi-07-02
Date: 2007
Author(s): Jianhan Zhu, Dawei Song, Stefan Rüger, Marc Eisenstadt, Enrico Motta
Resources: Relation Extraction for Semantic Intranet Annotations
We present an approach for ontology driven extraction of relations from texts aimed mainly to produce enriched semantic annotations for the Semantic Web. The approach exploits linguistic and empirical strategies, by means of a pipeline method involving processes such as a parser, part-of-speech tagger, named entity recognition system, and pattern-based classification, and resources including ontology, knowledge and lexical databases. A preliminary evaluation with 25 sentences showed that the...read more
SemSearch: A Search Engine for the Semantic Web
Semantic search promises to produce precise answers to user queries by taking advantage of the availability of explicit semantics of information in the context of the semantic web. Existing tools have been primarily designed to enhance the performance of traditional search technologies but with little support for naive users, i.e., ordinary end users who are not necessarily familiar with domain specific semantic data, ontologies, or SQL-like query languages. This paper presents SemSearch, a...read more
Probabilistic Methods for Data Integration in a Multi-Agent Query Answering System
This report describes a proposal for a multi agent ontology-mapping framework that makes use of probabilistic information in order to enhance the correctness of the mapping. The proposed research focuses on two correlated areas namely similarity measures with its representation as a Dempster-Shafer belief function and usability of different optimalisation methods for combining these belief functions in a distributed environment. The main goal of our proposed research is to establish a multi...read more
An Ontological Formalization of the Planning Task
In this report we propose a generic task ontology, which formalizes the space of planning problems. Although planning is one of the oldest researched areas in Artificial Intelligence and attempts have been made in the past at developing task ontologies for planning, these formalizations suffer from serious limitations: they do not exhibit the required level of formalization and precision and they usually fail to include some of the key concepts required for specifying planning problems. In...read more
A Generic Library of Problem Solving Methods for Scheduling Applications
In this report we propose a generic library of problem-solving methods for solving scheduling applications. Some attempts have been made in the past at developing a library scheduling problem-solvers but in some cases these earlier proposals subscribe to a specific application domain of scheduling, which restricted their reusability, while in some other cases they subscribe to the specific problem-solving technique which may be applicable only to a subset of the space of scheduling problems....read more
ID: kmi-05-11
Date: 2005
Author(s): Dnyanesh Rajpathak, Enrico Motta, Zdenek Zdrahal, and Rajkumar Roy
Resources: Experiences of Two Task Driven User Studies of Hypermedia Information Systems
We present two small scale user studies of hypermedia information systems: a hypermedia discourse system designed as an environment for researchers to summarize and share key ideas from research papers as a claim network, and a web browser plug-in which annotates terms related to a selected ontology on the fly. The first study investigated whether a claim network created by one user could help others learn about a domain. The second study investigated whether information extraction techniques...read more
ID: kmi-05-04
Date: 2005
Author(s): Victoria Uren, Philipp Cimiano, Simon Buckingham Shum, Enrico Motta
Resources: Ontology Mapping with domain specific agents in the AQUA Question Answering system
This paper describes a domain specific multi-agent ontology-mapping solution in the AQUA query answering system. In order to incorporate uncertainty inherent to the mapping process, the system uses the Dempster-Shafer model for dealing with incomplete and uncertain information produced during the mapping. A novel approach is presented how specialized agents with partial local knowledge of the particular domain achieve ontology mapping without creating global or reference ontology. Our approach...read more
ClaimSpotter: an Environment to Support Sensemaking with Knowledge Triples
Annotating a document with an interpretation of its contents raises a number of challenges that we are hoping to address via the creation of a supporting environment. We present these challenges and motivate an approach based on the notion of suggestions to support document annotation, hoping these suggestions would act as leads to follow for annotators, therefore reducing some of the difficulties inherent to the task. The environment resulting from this approach, ClaimSpotter, is presented....read more
AQUA: A Question Answering System for Heterogeneous Sources
This paper describes AQUA our question answering over the Web. AQUA was designed to work over heterogeneous sources. This means that AQUA is equipped to work as closed domain and in addition to open-domain question answering. As a first instance, AQUA tries to answer a question using a Knowledge base. If a query cannot be satisfied over a knowledge base/database. Then, AQUA tries to find an answer on web pages (i.e. it uses as corpus the internet as resource). Our system uses NLP (Natural...read more
A Knowledge-Based Approach to Ontologies Data Integration
This paper describes a proposal of multiple ontology data integration system for a question answering framework called AQUA. We propose an approach for mediating between a given query and a set of resources. This method is based on a Meta-ontology (which contains contents of each individual sources) and our similarity algorithm based on analysis of neighborhood of classes. We argue that AQUA can perform mappings between queries and an ontological space by using a mediator agent based on a...read more
An Ontology-Driven Similarity Algorithm
This paper presents our similarity algorithm between relations in a user query written in FOL (first order logic) and ontological relations. Our similarity algorithm takes two graphs and produces a mapping between elements of the two graphs (i.e. graphs associated to the query, a subsection of ontology relevant to the query). The algorithm assesses structural similarity and concept similarity. An evaluation of our algorithm using the KMi Planet ontology is presented. We also carried out an...read more
AQUA: A Knowledge-Based Architecture for a Question Answering System
This paper describes AQUA, a question answering system. AQUA combines Natural Language processing (NLP), Ontologies, Logic, and Information Retrieval technologies in a uniform framework. AQUA makes intensive use of an ontology (which encodes knowledge) in several parts of the question answering system. The ontology is used in the refinement of the initial query, the reasoning process (a generalization/specialization process using classes and subclasses from the ontology), and in the novel...read more
ESpotter: Adaptive Named Entity Recognition for Web Browsing
Web users are facing information overload problems, i.e., it is hard for them to find desired information on the web. Hence the growing interest in named entity recognition (NER) for discovering relevant information on users behalf. We present a browser plug-in called ESpotter which adapts lexicons and patterns to a domain hierarchy consisting of domains on the web and user preferences for accurate and efficient NER. Mappings are created from domain independent types to domain...read more
Ontology-driven Question Answering in AquaLog
The semantic web vision is one in which rich, ontology-based semantic markup is widely available, both to enable sophisticated interoperability among agents and to support human web users in locating and making sense of informa-tion. The availability of semantic markup on the web also opens the way to novel, sophisticated forms of question answering. AquaLog is a portable question-answering system which takes queries expressed in natural language and an ontol-ogy as input and...read more
Semantic Learning Webs
If current research is successful there will be a plethora of e-learning platforms making use of a varied menu of reusable educational material or learning objects. For the learner, the semanticized Web will, in addition, offer rich seams of diverse learning resources over and above the course materials (or learning objects) specified by course designers. This much is already in development. But we can go much further. Semantic technologies make it possible not only to reason about the Web as...read more
Semantic Annotation Support in the Absence of Consensus
We are interested in the annotation of knowledge which does not necessarily require a consensus. Scholarly debate is an example of such a category of knowledge where disagreement and contest are widespread and desirable, and unlike many Semantic Web approaches, we are interested in the capture and the compilation of these conflicting viewpoints and perspectives. The Scholarly Ontologies project provides the underlying formalism to represent this meta-knowledge, and we will look at ways to...read more
ID: kmi-04-01
Date: 2004
Author(s): Bertrand Sereno, Victoria Uren, Simon Buckingham Shum, Enrico Motta
Resources: MnM: A Tool for Automatic Support on Semantic Markup
An important precondition for realizing the goal of a semantic web is the ability to annotate web resources with semantic information. In order to carry out this task, users need appropriate representation languages, ontologies, and support tools. In this paper we present MnM, an annotation tool which provides both automated and semi-automated support for annotating web pages with semantic contents. MnM integrates a web browser with an ontology editor and provides open APIs to link to ontology...read more
ID: kmi-03-09
Date: 2003
Author(s): Maria Vargas-Vera, Enrico Motta, John Domingue, Mattia Lanzoni, Arthur Stutt, Fabio Ciravegna
Resources: AQUA - Ontology-based Question Answering System
This paper describes AQUA, an experimental question answering system. AQUA combines Natural Language processing (NLP), Ontologies, Logic, and Information Retrieval technologies in a uniform framework. AQUA makes intensive use of an ontology in several parts of the question answering system. The ontology is used in the refinement of the initial query, the reasoning process (a generalization or specialization process using classes and subclasses from the ontology), and in the novel similarity...read more
An Ontology-Driven Question Answering System (AQUA)
This paper describes AQUA, an experimental question answering system. AQUA combines Natural Language processing (NLP), Ontologies, Logic, and Information Retrieval technologies in a uniform framework. AQUA makes intensive use of an ontology in several parts of the question answering system. The ontology is used in the refinement of the initial query, the reasoning process (a generalization/specialization process using classes and subclasses from the ontology), and in the novel similarity...read more
Scholarly Publishing and Argument in Hyperspace
The World Wide Web is opening up access to documents and data for scholars. However it has not yet impacted on one of the primary activities in research: assessing new findings in the light of current knowledge and debating it with colleagues. The ClaiMaker system uses a directed graph model with similarities to hypertext, in which new ideas are published as nodes, which other contributors can build on or challenge in a variety of ways by linking to them. Nodes and links have semantic structure...read more
ID: kmi-03-03
Date: 2003
Author(s): Victoria Uren, Simon Buckingham Shum, Gangmin Li, John Domingue, Enrico Motta
Resources: ClaiMaker:Weaving a Semantic Web of Research Papers
The usability of research papers on the Web would be enhanced by a system that explicitly modelled the rhetorical relations between claims in related papers. We describe ClaiMaker, a system for modelling readers' interpretations of the core content of papers. ClaiMaker provides tools to build a Semantic Web representation of the claims in research papers using an ontology of relations. We demonstrate how the system can be used to make inter-document queries.read more
ID: kmi-03-02
Date: 2003
Author(s): Gangmin Li, Victoria Uren, Enrico Motta, Simon Buckingham Shum, John Domingue
Resources: Semantic Layering with Magpie
Browsing the web involves two main tasks: finding the right web page and then making sense of its content. A significant amount of research has gone into supporting the task of finding web resources through standard information retrieval mechanisms, or semantics-enhanced search. Much less attention has been paid to the second problem. In this paper we describe Magpie, a tool which supports the interpretation of web pages. Magpie acts as a complementary knowledge source, which a reader can...read more
Beyond Rigid KA Metatools: An Initial Proposal for a KR-Independent, Adaptive, Customizable, Ontology-based KA Metatool
This paper proposes a new knowledge-acquisition metatool, KRIACO, a Web-based, Knowledge Representation Independent, Adaptive, Customizable, Ontology-based Knowledge Acquisition Metatool, which aims to overcome sorts of shortcomings of current knowledge acquisition metatools. To achieve its goal, KRIACO will adopt OKBC as an underlying knowledge representation model to overcome the restriction caused by a specific knowledge representation system. It will use an ontology-driven tool...read more
Integration of Information Extraction with an Ontology
This paper describes the integration of an ontology with an information extraction (IE) tool. Our main goal is extract knowledge from text to populate the ontology, and so alleviate the problem of ontology maintenance. The IE tool extracts information using partial parsing and machine learning techniques. Our domain of study is ``KMi Planet'', a Web-based news server that helps to communicate relevant information between members in our institute. Currently our system finds instances of...read more
ID: kmi-01-12
Date: 2001
Author(s): Maria Vargas-Vera, John Domingue, Yannis Kalfoglou, Enrico Motta and Simon Buckingham Shum
Resources: On the integration of technologies for capturing and navigating knowledge with ontology-driven services
"Nowadays, many distinct communities are researching on technologies for knowledge capturing, modelling, and navigation. Moreover, advances in Internet technology makes it possible to perform most of these tasks on heterogeneous and distributed environments such as the Web. These advances though, have raise the need for knowledge services to accommodate the ever increasing number of Web users. To provide such a service one needs to combine key technologies for different aspects of knowledge...read more
ID: kmi-01-11
Date: 2001
Author(s): Yannis Kalfoglou, John Domingue, Leslie Carr, Enrico Motta, Maria Vargas-Vera, Simon Buckingham Shum
Resources: Template-Driven Information Extraction for Populating Ontologies
We address the integration of information extraction (IE) and ontologies. In particular, using an ontology to aid the IE process, and using the IE results to help populate the ontology. We perform IE by means of domain specific templates and the lightweight use of Natural Languages Processing techniques (NLP). Our main goal is to learn information from text by the use of templates and in this way to alleviate the main bottleneck in creating knowledge-base systems that is ``the...read more
ID: kmi-01-08
Date: 2001
Author(s): Maria Vargas-Vera, John Domingue, Yannis Kalfoglou, Enrico Motta and Simon Buckingham-Shum
Resources: Compendium: Making Meetings into Knowledge Events
In this paper, we describe the Compendium methodology and suite of tools. Compendium is the result of over a decade's research and development at the intersection of collaborative modeling, organizational memory, computer-supported argumentation and meeting facilitation. We claim that Compendium offers innovative strategies for tackling several of the key challenges in managing knowledge: · improving communication between disparate communities tackling ill-structured problems · ...read more
ID: kmi-01-06
Date: 2001
Author(s): Albert Selvin, Simon Buckingham Shum, Maarten Sierhuis, Jeff Conklin, Beatrix Zimmermann, Charles Palus, Wilfred Drath, David Horth, John Domingue, Enrico Motta and Gangmin Li
Resources: Scholarly Discourse as Computable Structure
In their initial proposal for structural computing (SC), Nrnberg et al. [18] point to hypertext argumentation systems as an example of an application domain in which structure is of first-order importance. In this paper we summarise the goals and implementation of a knowledge based hypertext environment called ScholOnto (for Scholarly Ontologies), which aims to provide researchers with computational support in representing and analysing the structure of scholarly claims, argumentation and...read more
Case Studies in Ontology-Driven Document Enrichment
In this paper we present an approach to document enrichment, which consists of associating formal knowledge models to archives of documents, to provide intelligent knowledge retrieval and (possibly) additional knowledge services, beyond what is available using 'standard' information retrieval and search facilities. The approach is ontology-driven, in the sense that the construction of the knowledge model is carried out in a top-down fashion, by populating a given ontology, rather than in a...read more
Representing Scholarly Claims in Internet Digital Libraries: A Knowledge Modelling Approach
This paper is concerned with tracking and interpreting scholarly documents in distributed research communities. We argue that current approaches to document description, and current technological infrastructures particularly over the World Wide Web, provide poor support for these tasks. We describe the design of a digital library server which will enable authors to submit a summary of the contributions they claim their documents makes, and its relations to the literature. We describe a...read more
Reusable Components for Knowledge Modelling
This book addresses issues of knowledge modelling and reuse.What is the appropriate framework for modelling intelligent problem solving? How best to model reusable knowledge resources? How should libraries of reusable components be organized? I try to answer these questions by describing a comprehensive approach to the specification, organization, configuration and use of reusable components for knowledge models. Hence, the book addresses both theoretical and engineering issues. It proposes a...read more
Improving Competence by Integrating Case-Based Reasoning and Heuristic Search
We analyse the behaviour of a Propose & Revise architecture in the VT elevator design problem and we show that this problem solving method cannot solve all possible cases covered by the available domain knowledge. We investigate this problem and we show that this limitation is caused by the restricted search regime employed by the method and that the competence of the method cannot be improved by acquiring additional domain knowledge. We therefore propose an alternative design problem solver,...read more
Parametric Design Problem Solving
The aim of this paper is to understand what is involved in parametric design problem solving. In order to achieve this goal, in this paper i) we identify and detail the conceptual elements defining a parametric design task specification; ii) we illustrate how these elements are interpreted and operationalised during the design process; and iii) we formulate a generic model of parametric design problem solving. We then re-describe a number of problem solving methods in terms of the proposed...read more
A Taxonomy of Intellectual Capital and a Methodology for Auditing It
Ownership of intellectual property is rarely measured. While many companies spend huge amounts of money filing and protecting patents, too often that activity is defensive. Patents are not exercised and do not generate wealth for the inventor. Their windows of opportunity remain a mystery to their owners, as does their value. Organisations that are unaware of the value of their intellectual property are missing an important asset that ought to be included in any exercise which aims to measure...read more
Solving VT in VITAL: A Study in Model Construction and Knowledge Reuse
In this paper we discuss a solution to the Sisyphus II elevator design problem developed using the VITAL approach to structured knowledge-based system development. In particular we illustrate in detail the process by which an initial model of Propose&Revise problem solving was constructed using a generative grammar of model fragments and then refined and operationalised in the VITAL operational conceptual modelling language (OCML). In the paper we also discuss in detail the properties of a...read more
ID: kmi-95-09
Date: 1995
Author(s): Enrico Motta, *Kieron O'Hara, *Nigel Shadbolt, Arthur Stutt and Zdenek Zdrahal
Resources:Recording the design decisions of knowledge engineers to facilitate re-use of design models
In this paper we focus on the process of constructing reusable knowledge level models by augmenting an explicit process model of KBS design with a means of recording the argumentation about design decisions. Our method includes a set of design principles and an expressive design language for representing design components (such as tasks and roles) with an extension for decision descriptions. We present a concrete example of the application of our design methodology which illustrates how our...read more
The Trouble with What: Issues in method-independent task specifications
In this paper we discuss some issues concerning the organization of knowledge for reuse and we critically examine the ideas of knowledge separation and minimal ontological commitments.. Because knowledge structures can play multiple roles in a domain, it is not necessarily the case that search-control knowledge can be neatly separated from a domain ontology. This is particularly the case when only procedural descriptions of a task are available. Because expert knowledge is often `messy', clean...read more
Reusable and Maintainable KBS Design
The VITAL Design Methodology is augmented with a means of recording argumentation so as to produce reusable knowledge level models.read more
The Emerging VITAL Workbench
VITAL is a research and development project which aims to provide methodological and software support for developing large, embedded KBS applications. VITAL is novel in that its ambition is to develop a methodology-based workbench covering the whole KBS life-cycle, from requirements specification to implementation, and to integrate and deploy a number of techniques drawn from artificial intelligence, as well as software engineering and human-computer interaction fields of research. In this...read more
