The Semantic Web -- 6th International Semantic Web Conference, 2nd Asian Semantic Web Conference, ISWC 2007 + ASWC 2007, Busan, Korea, November 11-15, 2007. Proceedings

Doctoral Consortium Paper

1. Cultural Adaptivity for the Semantic Web , Katharina Reinecke , 946-950 , [OpenAccess] , [Publisher]
   Our research explores the possibilities for factoring culture into user models, working towards cultural adaptivity in the Semantic Web. The aim is to automate the localization process by acquiring details about an individual's cultural background. The paper shows how we have based our approach on research findings from related fields, outlining the connection between the cultural user and domain model ontologies, and a test environment. Furthermore, we describe a preliminary plan of how to validate our cultural user model by comparison to our previous experience in the manual adaptation of imbuto.
2. Exploiting Patterns in Ontology Mapping , Ondrej Sváb , 956-960 , [OpenAccess] , [Publisher]
   Unsatisfactory performance of ontology mapping methods on many tasks seems to indicate the need for employing some background knowledge. My PhD work focuses on exploiting pattern-like structures for this purpose. Design patterns are related to different styles of modelling ontology structure and/or naming of concepts. On the other hand, mapping patterns emerge as result of the mapping process. Preliminary results and schedule of future work are presented.
3. From Texts to Structured Documents: The Case of Health Practice Guidelines , Amanda Bouffier , 916-920 , [OpenAccess] , [Publisher]
   This paper describes a system capable of semi-automatically filling an XML template from free texts in the clinical domain (practice guidelines). The XML template includes semantic information not explicitly encoded in the text (pairs of conditions and actions/recommendations). Therefore, there is a need to compute the exact scope of conditions over text sequences expressing the required actions. We present a system developed for this task. We show that it yields good performance when applied to the analysis of French practice guidelines.
4. Integrating Uncertainty into Ontology Mapping , Ying Wang , 961-965 , [OpenAccess] , [Publisher]
   This paper gives an outline of my PhD thesis which describes the integration of managing uncertainty into ontology mapping. Ontology mapping is one of the most important tasks for ontology interoperability and its main aim is to find semantic relationships between entities (i.e. concept, attribute, and relation) of two ontologies, However, in the process of mapping, uncertainty and incompleteness of semantics in the syntactic representation and description of relations between entities in ontologies will lead to imprecise results. If we want to obtain better results, it becomes more significant for the ontology mapping to be able to deal with uncertainty.
5. Knowledge Enhanced Searching on the Web , Afraz Jaffri , 921-925 , [OpenAccess] , [Publisher]
   The move towards a semantic web has been in progress for many years and more recently there have been applications that make use of semantic web technology. One of the features that made the Web so easy to use is the ability to search web pages in a matter of seconds through the use of search engines. Now that the use of OWL and RDF as a knowledge representation format is increasing, the possibility appears to improve the quality of searching by using the semantic web to enhance the 'ordinary' Web. This paper outlines an architecture for using distributed knowledge bases to assist and improve searching on the web.
6. Lightweight Community-Driven Ontology Evolution , Katharina Siorpaes , 951-955 , [OpenAccess] , [Publisher]
   Only few well-maintained domain ontologies can be found on the Web. The reasons for the lack of useful domain ontologies include that (1) informal means to convey intended meaning more efficiently are used for ontology specification only to a very limited extent, (2) many relevant domains of discourse show a high degree of conceptual dynamics, (3) ontology representation languages are hard to understand for the majority of (potential) ontology users, and (4) the community does not have control over the ontology evolution. In my thesis, on which I have been working for 9 months, I propose to (1) base a methodology for community-grounded ontology building on the culture and philosophy of Wikis by giving users who have no or little expertise in ontology engineering the opportunity to contribute in all stages of the ontology lifecycle and (2) exploit the combination of human and computational intelligence to discover and resolve inconsistencies and align lightweight domain ontologies. The contribution of my thesis is a methodology for community-grounded building and evolution of lightweight domain ontologies.
7. Mutual Contextualization in Tripartite Graphs of Folksonomies , Ching-man Au Yeung,Nicholas Gibbins and Nigel Shadbolt , 966-970 , [OpenAccess] , [Publisher]
   The use of tags to describe Web resources in a collaborative manner has experienced rising popularity among Web users in recent years. The product of such activity is given the name folksonomy, which can be considered as a scheme of organizing information in the users' own way. This research work attempts to analyze tripartite graphs - graphs involving users, tags and resources - of folksonomies and discuss how these elements acquire their semantics through their associations with other elements, a process we call mutual contextualization. By studying such process, we try to identify solutions to problems such as tag disambiguation, retrieving documents of similar topics and discovering communities of users. This paper describes the basis of the research work, mentions work done so far and outlines future plans.
8. OWL-DL as a Power Tool to Model Negotiation Mechanisms with Incomplete Information , Azzurra Ragone , 941-945 , [OpenAccess] , [Publisher]
   We propose a framework to model negotiations among agents in scenarios withfully incomplete information. We address multi-issue bilateral negotiations, where issues are expressed and related to each other via an OWL ontology. In particular we use OWL DL sub-language - as it is the "official language" of the Semantic Web communities - and exploit its formal semantics based on the Description Logic SHOIN(D). Agents goals are expressed through OWL-DL as (complex) concept expressions, and the worth of goals as weights over concepts. We adopt a very general setting with incomplete information by letting agents keep both goals and worths of goals as private information. Moreover we propose a framework through which agents can negotiate and reach an agreement. Agents, according to the protocol, can pursue different sets of strategies, depending on their type.
9. Ontology Mapping: An Information Retrieval and Interactive Activation Network Based Approach , Ming Mao , 931-935 , [OpenAccess] , [Publisher]
   The World Wide Web (WWW) now is widely used as a universal medium for information exchange. Semantic interoperability among different information systems in the WWW is limited due to information heterogeneity problem. Ontologies have been suggested as a way to solve this problem. Given that no universal ontology exists for the WWW, work has focused on finding semantic correspondences between similar elements of different ontologies, i.e., ontology mapping. Ontology mapping can be done either by hand or using automated tools. Manual mapping becomes impractical as the size and complexity of ontologies increases. Fully or semi-automated mapping approaches have been examined by different research studies, e.g., analyzing linguistic information of elements in ontologies, treating ontologies as structural graphs, applying heuristic rules to look for specific mapping patterns and machine learning techniques. This paper proposes a new generic and scalable ontology mapping approach, which takes advantage of propagation theory, information retrieval technique and artificial intelligence model to solve ontology mapping problem. The major procedures of the proposed approach are profile enrichment, profile propagation, IR-based profile mapping and the interactive activation network based constraints satisfaction. The profile enrichment builds a profile for each element in the ontologies, and thus enriches its information. The profile propagation exploits the neighboring information of each element by passing the profile of the ancestors, descendants or siblings of the element to the profile of itself, with different weights. The IR-based profile mapping process compares the cosine similarity of elements' profiles in a vector space model. Finally the interactive activation network is integrated to deal with the constraints satisfaction problems in the context of ontology mapping.
10. Ontology-Driven Management of Semantic Spaces , Reto Krummenacher , 926-930 , [OpenAccess] , [Publisher]
    Recent work in the field of middleware technology proposes semantic spaces as a tool for coping with the scalability, heterogeneity and dynamism issues of large scale distributed environments. Reflective middleware moreover offers answers to the needs for adaptivity and self-determination of systems. Based on experiences with traditional middleware we argue that ontology-driven management is a major advancement for semantic spaces and provides the fundamental means for reflection. In this research we look at ontology-based metadata to turn semantic spaces into reflective middleware.
11. Probabilistic Information Integration and Retrieval in the Semantic Web , Livia Predoiu , 936-940 , [OpenAccess] , [Publisher]
    This paper proposes research on a probabilistic framework for information integration and retrieval in the Semantic Web. The framework aims at integrating probabilistic and deterministic DL and LP knowledge bases.
12. Semi-automatic Ontology Engineering Using Patterns , Eva Blomqvist , 911-915 , [OpenAccess] , [Publisher]
    Many enterprise systems face the same kind of information processing problems that exist on the web in general, and creating semantic solutions often involve constructing an enterprise ontology. Ontology engineering in turn needs to be semi-automatic in order to reduce the effort and need for expertise. By introducing knowledge reuse in ontology construction the construction effort can be further reduced and the quality of the ontology output increased. The proposed research focuses on a hybrid approach for ontology construction based on the methodology of case-based reasoning in combination with ontology patterns.

Research Track Paper

1. A Caching Mechanism for Semantic Web Service Discovery , Michael Stollberg,Martin Hepp and Jörg Hoffmann , 480-493 , [OpenAccess] , [Publisher]
   The discovery of suitable Web services for a given task is one of the central operations in Service-oriented Architectures (SOA), and research on Semantic Web services (SWS) aims at automating this step. For the large amount of available Web services that can be expected in real-world settings, the computational costs of automated discovery based on semantic matchmaking become important. To make a discovery engine a reliable software component, we must thus aim at minimizing both the mean and the variance of the duration of the discovery task. For this, we present an extension for discovery engines in SWS environments that exploits structural knowledge and previous discovery results for reducing the search space of consequent discovery operations. Our prototype implementation shows significant improvements when applied to the Stanford SWS Challenge scenario and dataset.
2. A Cognitive Support Framework for Ontology Mapping , Sean M. Falconer and Margaret-Anne D. Storey , 114-127 , [OpenAccess] , [Publisher]
   Ontology mapping is the key to data interoperability in the semantic web. This problem has received a lot of research attention, however, the research emphasis has been mostly devoted to automating the mapping process, even though the creation of mappings often involve the user. As industry interest in semantic web technologies grows and the number of widely adopted semantic web applications increases, we must begin to support the user. In this paper, we combine data gathered from background literature, theories of cognitive support and decision making, and an observational case study to propose a theoretical framework for cognitive support in ontology mapping tools. We also describe a tool called CogZ that is based on this framework.
3. A Method for Recommending Ontology Alignment Strategies , He Tan and Patrick Lambrix , 494-507 , [OpenAccess] , [Publisher]
   In different areas ontologies have been developed and many of these ontologies contain overlapping information. Often we would therefore want to be able to use multiple ontologies. To obtain good results, we need to find the relationships between terms in the different ontologies, i.e. we need to align them. Currently, there already exist a number of different alignment strategies. However, it is usually difficult for a user that needs to align two ontologies to decide which of the different available strategies are the most suitable. In this paper we propose a method that provides recommendations on alignment strategies for a given alignment problem. The method is based on the evaluation of the different available alignment strategies on several small selected pieces from the ontologies, and uses the evaluation results to provide recommendations. In the paper we give the basic steps of the method, and then illustrate and discuss the method in the setting of an alignment problem with two well-known biomedical ontologies. We also experiment with different implementations of the steps in the method.
4. AllRight: Automatic Ontology Instantiation from Tabular Web Documents , Kostyantyn M. Shchekotykhin,Dietmar Jannach,Gerhard Friedrich and Olga Kozeruk , 466-479 , [OpenAccess] , [Publisher]
   The process of instantiating an ontology with high-quality and up-to-date instance information manually is both time consuming and prone to error. Automatic ontology instantiation from Web sources is one of the possible solutions to this problem and aims at the computer supported population of an ontology through the exploitation of (redundant) information available on the Web. In this paper we present AllRight, a comprehensive ontology instantiating system. In particular, the techniques implemented in AllRight are designed for application scenarios, in which the desired instance information is given in the form of tables and for which existing Information Extraction approaches based on statistical or natural language processing methods are not directly applicable. Within AllRight, we have therefore developed new techniques for dealing with tabular instance data and combined these techniques with existing methods. The system supports all necessary steps for ontology instantiation, i.e. web crawling, name extraction, document clustering as well as fact extraction and validation. AllRight has been successfully evaluated in the popular domains of digital cameras and notebooks leading to a about eighty percent accuracy of the extracted facts given only a very limited amount of seed knowledge.
5. Alternating-Offers Protocol for Multi-issue Bilateral Negotiation in Semantic-Enabled Marketplaces , Azzurra Ragone,Tommaso Di Noia,Eugenio Di Sciascio and Francesco M. Donini , 395-408 , [OpenAccess] , [Publisher]
   We present a semantic-based approach to multi-issue bilateral negotiation for e-commerce. We use Description Logics to model advertisements, and relations among issues as axioms in a TBox. We then introduce a logic-based alternating-offers protocol, able to handle conflicting information, that merges non-standard reasoning services in Description Logics with utility thoery to find the most suitable agreements. We illustrate and motivate the theoretical framework, the logical language, and the negotiation protocol.
6. An Empirical Study of Instance-Based Ontology Matching , Antoine Isaac,Lourens van der Meij,Stefan Schlobach and Shenghui Wang , 253-266 , [OpenAccess] , [Publisher]
   Instance-based ontology mapping is a promising family of solutions to a class of ontology alignment problems. Instance-based ontology mapping crucially depends on measuring the similarity between sets of annotated instances. In this paper we study how the choice of co-occurrence measures affects the performance of instance-based mapping. To this end, we have implemented a number of different statistical co-occurrence measures. We have prepared an extensive test case using vocabularies of thousands of terms, millions of instances, and hundreds of thousands of co-annotated items, and we have obtained a human Gold Standard judgement for part of the mapping-space. We then study how the different co-occurrence measures and a number of algorithmic variations perform on our benchmark dataset, as compared against the GoldStandard. Our systematic study shows excellent results of instance-based matching in general, where the more simple measures often outperform more sophisticated statistical co-occurrence measures.
7. An Event-Based Approach for Semantic Metadata Interoperability , Tuukka Ruotsalo and Eero Hyvönen , 409-422 , [OpenAccess] , [Publisher]
   This paper presents a method for making metadata conforming to heterogeneous schemas semantically interoperable. The idea is to make the knowledge embedded in the schema structures interoperable and explicit by transforming the schemas into a shared, event-based representation of knowledge about the real world. This enables and simplifies accurate reasoning services such as cross-domain semantic search, browsing, and recommending. A case study of transforming three different schemas and datasets is presented. An implemented knowledge-based recommender system utilizing the results in the semantic portal CULTURESAMPO was found useful in a preliminary user study.
8. An Ontology Design Pattern for Representing Relevance in OWL , Fernando Bobillo,Miguel Delgado and Juan Gómez-Romero , 72-85 , [OpenAccess] , [Publisher]
   Design patterns are widely-used software engineering abstractions which define guidelines for modeling common application scenarios. Ontology design patterns are the extension of software patterns for knowledge acquisition in the Semantic Web. In this work we present a design pattern for representing relevance depending on context in OWL ontologies, i.e. to assert which knowledge from the domain ought to be considered in a given scenario. Besides the formal semantics and the features of the pattern, we describe a reasoning procedure to extract relevant knowledge in the resulting ontology and a plug-in for Protege which assists pattern use.
9. An Unsupervised Model for Exploring Hierarchical Semantics from Social Annotations , Mianwei Zhou,Shenghua Bao,Xian Wu and Yong Yu , 680-693 , [OpenAccess] , [Publisher]
   This paper deals with the problem of exploring hierarchical semantics from social annotations. Recently, social annotation services have become more and more popular in Semantic Web. It allows users to arbitrarily annotate web resources, thus, largely lowers the barrier to cooperation. Furthermore, through providing abundant meta-data resources, social annotation might become a key to the development of Semantic Web. However, on the other hand, social annotation has its own apparent limitations, for instance, 1) ambiguity and synonym phenomena and 2) lack of hierarchical information. In this paper, we propose an unsupervised model to automatically derive hierarchical semantics from social annotations. Using a social bookmark service Del.icio.us as example, we demonstrate that the derived hierarchical semantics has the ability to compensate those shortcomings. We further apply our model on another data set from Flickr to testify our model's applicability on different environments. The experimental results demonstrate our model's effciency.
10. Automatically Composing Data Workflows with Relational Descriptions and Shim Services , José Luis Ambite and Dipsy Kapoor , 15-29 , [OpenAccess] , [Publisher]
    Many scientific problems can be represented as computational workflows of operations that access remote data, integrate heterogeneous data, and analyze and derive new data. Even when the data access and processing operations are implemented as web or grid services, workflows are often constructed manually in languages such as BPEL. Adding semantic descriptions of the services enables automatic or mixed-initiative composition. In most previous work, these descriptions consists of semantic types for inputs and outputs of services or a type for the service as a whole. While this is certainly useful, we argue that is not enough to model and construct complex data workflows. We present a planning approach to automatically constructing data processing workflows where the inputs and outputs of services are relational descriptions in an expressive logic. Our workflow planner uses relational subsumption to connect the output of a service with the input of another. This modeling style has the advantage that adaptor services, so-called shims, can be automatically inserted into the workflow where necessary.
11. Bringing Semantic Annotations to Web Services: OWL-S from the SAWSDL Perspective , David Martin,Massimo Paolucci and Matthias Wagner , 340-352 , [OpenAccess] , [Publisher]
    Recently, the World Wide Web Consortium (W3C) produced a standard set of "Semantic Annotations for WSDL and XML Schema" (SAWSDL). SAWSDL provides a standard means by which WSDL documents can be related to semantic descriptions, such as those provided by OWL-S (OWL for Services) and other Semantic Web services frameworks. We argue that the value of SAWSDL cannot be realized until its use is specified, and its benefits explained, in connection with a particular framework. This paper is an important first step toward meeting that need, with respect to OWL-S. We explain what OWL-S constructs are appropriate for use with the various SAWSDL annotations, and provide a rationale and guidelines for their use. In addition, we discuss some weaknesses of SAWSDL, and identify some ways in which OWL-S could evolve so as to integrate more smoothly with SAWSDL.
12. CLOnE: Controlled Language for Ontology Editing , Adam Funk,Valentin Tablan,Kalina Bontcheva,Hamish Cunningham,Brian Davis and Siegfried Handschuh , 142-155 , [OpenAccess] , [Publisher]
    This paper presents a controlled language for ontology editing and a software implementation, based partly on standard NLP tools, for processing that language and manipulating an ontology. The input sentences are analysed deterministically and compositionally with respect to a given ontology, which the software consults in order to interpret the input's semantics; this allows the user to learn fewer syntactic structures since some of them can be used to refer to either classes or instances, for example. A repeated-measures, task-based evaluation has been carried out in comparison with a well-known ontology editor; our software received favourable results for basic tasks. The paper also discusses work in progress and future plans for developing this language and tool.
13. COMM: Designing a Well-Founded Multimedia Ontology for the Web , Richard Arndt,Raphaël Troncy,Steffen Staab,Lynda Hardman and Miroslav Vacura , 30-43 , [OpenAccess] , [Publisher]
    Semantic descriptions of non-textual media available on the web can be used to facilitate retrieval and presentation of media assets and documents containing them. While technologies for multimedia semantic descriptions already exist, there is as yet no formal description of a high quality multimedia ontology that is compatible with existing (semantic) web technologies. We explain the complexity of the problem using an annotation scenario. We then derive a number of requirements for specifying a formal multimedia ontology before we present the developed ontology, COMM, and evaluate it with respect to our requirements. We provide an API for generating multimedia annotations that conform to COMM.
14. Conjunctive Queries for a Tractable Fragment of OWL 1.1 , Markus Krötzsch,Sebastian Rudolph and Pascal Hitzler , 310-323 , [OpenAccess] , [Publisher]
    Despite the success of the Web Ontology Language OWL, the development of expressive means for querying OWL knowledge bases is still an open issue. In this paper, we investigate how a very natural and desirable form of queries - namely conjunctive ones - can be used in conjunction with OWL such that one of the major design criteria of the latter - namely decidability - can be retained. More precisely, we show that querying the tractable fragment EL++ of OWL 1.1 is decidable. We also provide a complexity analysis and show that querying unrestricted EL++ is undecidable.
15. Continuous RDF Query Processing over DHTs , Erietta Liarou,Stratos Idreos and Manolis Koubarakis , 324-339 , [OpenAccess] , [Publisher]
    We study the continuous evaluation of conjunctive triple pattern queries over RDF data stored in distributed hash tables. In a continuous query scenario network nodes subscribe with long-standing queries and receive answers whenever RDF triples satisfying their queries are published. We present two novel query processing algorithms for this scenario and analyze their properties formally. Our performance goal is to have algorithms that scale to large amounts of RDF data, distribute the storage and query processing load evenly and incur as little network traffic as possible. We discuss the various performance tradeoffs that occur through a detailed experimental evaluation of the proposed algorithms.
16. Creating a Dead Poets Society: Extracting a Social Network of Historical Persons from the Web , Gijs Geleijnse and Jan H. M. Korst , 156-168 , [OpenAccess] , [Publisher]
    We present a simple method to extract information from search engine snippets. Although the techniques presented are domain independent, this work focuses on extracting biographical information of historical persons from multiple unstructured sources on the Web. We first similarly find a list of persons and their periods of life by querying the periods and scanning the retrieved snippets for person names. Subsequently, we find biographical informationfor the persons extracted. In order to get insight in the mutual relations among the persons identified, we create a social network using co-occurrences on the Web. Although we use uncontrolled and unstructured Web sources, the information extracted is reliable. Moreover we show that Web Information Extraction can be used to create both informative and enjoyable applications.
17. Discovering Simple Mappings Between Relational Database Schemas and Ontologies , Wei Hu and Yuzhong Qu , 225-238 , [OpenAccess] , [Publisher]
    Ontologies proliferate with the growth of the Semantic Web. However, most of data on the Web are still stored in relational databases. Therefore, it is important to establish interoperability between relational databases and ontologies for creating a Web of data. An effective way to achieve interoperability is finding mappings between relational database schemas and ontologies. In this paper, we propose a new approach to discovering simple mappings between a relational database schema and an ontology. It exploits simple mappings based on virtual documents, and eliminates incorrect mappings via validating mapping consistency. Additionally, it also constructs a special type of semantic mappings, called contextual mappings, which is useful for practical applications. Experimental results demonstrate that our approach performs well on several data sets from real world domains.
18. Enabling Advanced and Context-Dependent Access Control in RDF Stores , Fabian Abel,Juri Luca De Coi,Nicola Henze,Arne Wolf Koesling,Daniel Krause and Daniel Olmedilla , 1-14 , [OpenAccess] , [Publisher]
    Semantic Web databases allow efficient storage and access to RDF statements. Applications are able to use expressive query languages in order to retrieve relevant metadata in order to perform different tasks. However, access to metadata may not be public to just any application or service. Instead, powerful and flexible mechanisms for protecting sets of RDF statements are required for many Semantic Web applications. Unfortunately, current RDF stores do not provide fine-grained protection. This paper fills this gap and presents a mechanism by which complex and expressive policies can be specified in order to protect access to metadata in multi-service environments.
19. Evaluating the Semantic Web: A Task-Based Approach , Marta Sabou,Jorge Gracia,Sofia Angeletou,Mathieu d'Aquin and Enrico Motta , 423-437 , [OpenAccess] , [Publisher]
    The increased availability of online knowledge has led to the design of several algorithms that solve a variety of tasks by harvesting the Semantic Web, i.e., by dynamically selecting and exploring a multitude of online ontologies. Our hypothesis is that the performance of such novel algorithms implicitly provides an insight into the quality of the used ontologies and thus opens the way to a task-based evaluation of the Semantic Web. We have investigated this hypothesis by studying the lessons learnt about online ontologies when used to solve three tasks: ontology matching, folksonomy enrichment, and word sense disambiguation. Our analysis leads to a suit of conclusions about the status of the Semantic Web, which highlight a number of strengths and weaknesses of the semantic information available online and complement the findings of other analysis of the Semantic Web landscape.
20. Finding All Justifications of OWL DL Entailments , Aditya Kalyanpur,Bijan Parsia,Matthew Horridge and Evren Sirin , 267-280 , [OpenAccess] , [Publisher]
    Finding the justifications of an entailment (that is, all the minimal set of axioms sufficient to produce an entailment) has emerged as a key inference service for the Web Ontology Language (OWL). Justifications are essential for debugging unsatisfiable classes and contradictions. The availability of justifications as explanations of entailments improves the understandability of large and complex ontologies. In this paper, we present several algorithms for computing all the justifications of an entailment in an OWL-DL Ontology and show, by an empirical evaluation, that even a reasoner independent approach works well on real ontologies.
21. From Web Directories to Ontologies: Natural Language Processing Challenges , Ilya Zaihrayeu,Lei Sun,Fausto Giunchiglia,Wei Pan,Qi Ju,Mingmin Chi and Xuanjing Huang , 623-636 , [OpenAccess] , [Publisher]
    Hierarchical classifications are used pervasively by humans as a means to organize their data and knowledge about the world. One of their main advantages is that natural language labels, used to describe their contents, are easily understood by human users. However, at the same time, this is also one of their main disadvantages as these same labels are ambiguous and very hard to be reasoned about by software agents. This fact creates an insuperable hindrance for classifications to being embedded in the Semantic Web infrastructure. This paper presents an approach to converting classifications into lightweight ontologies, and it makes the following contributions: (i) it identifies the main NLP problems related to the conversion process and shows how they are different from the classical problems of NLP; (ii) it proposes heuristic solutions to these problems, which are especially effective in this domain; and (iii) it evaluates the proposed solutions by testing them on DMoz data.
22. History Matters: Incremental Ontology Reasoning Using Modules , Bernardo Cuenca Grau,Christian Halaschek-Wiener and Yevgeny Kazakov , 183-196 , [OpenAccess] , [Publisher]
    The development of ontologies involves continuous but relatively small modifications. Existing ontology reasoners, however, do not take advantage of the similarities between different versions of an ontology. In this paper, we propose a technique for incremental reasoning - that is, reasoning that reuses information obtained from previous versions of an ontology - based on the notion of a module. Our technique does not depend on a particular reasoning calculus and thus can be used in combination with any reasoner. We have applied our results to incremental classification of OWL DL ontologies and found significant improvement over regular classification time on a set of real-world ontologies.
23. How Service Choreography Statistics Reduce the Ontology Mapping Problem , Paolo Besana and Dave Robertson , 44-57 , [OpenAccess] , [Publisher]
    In open and distributed environments ontology mapping provides interoperability between interacting actors. However, conventional mapping systems focus on acquiring static information, and on mapping whole ontologies, which is infeasible in open systems. This paper shows that the interactions themselves between the actors can be used to predict mappings, simplifying dynamic ontology mapping. The intuitive idea is that similar interactions follow similar conventions and patterns, which can be analysed. The computed model can be used to suggest the possible mappings for the exchanged messages in new interactions. The suggestions can be evaluate by any standard ontology matcher: if they are accurate, the matchers avoid evaluating mappings unrelated to the interaction. The minimal requirement in order to use this system is that it is possible to describe and identify the interaction sequences: the OpenKnowledge project has produced an implementation that demonstrates this is possible in a fully peer-to-peer environment.
24. How Useful Are Natural Language Interfaces to the Semantic Web for Casual End-Users? , Esther Kaufmann and Abraham Bernstein , 281-294 , [OpenAccess] , [Publisher]
    Natural language interfaces offer end-users a familiar and convenient option for querying ontology-based knowledge bases. Several studies have shown that they can achieve high retrieval performance as well as domain independence. This paper focuses on usability and investigates if NLIs are useful from an end-user's point of view. To that end, we introduce four interfaces each allowing a different query language and present a usability study benchmarking these interfaces. The results of the study reveal a clear preference for full sentences as query language and confirm that NLIs are useful for querying Semantic Web data.
25. Instance Migration in Heterogeneous Ontology Environments , Luciano Serafini and Andrei Tamilin , 452-465 , [OpenAccess] , [Publisher]
    In this paper we address the problem of migrating instances between heterogeneous overlapping ontologies. The instance migration problem arises when one wants to reclassify a set of instances of a source ontology into a semantically related target ontology. Our approach exploits mappings between ontologies, which are used to reconcile both conceptual and individual level heterogeneity, and further used to draw the migration process. We ground the approach on a distributed description logic (DDL), in which ontologies are formally encoded as DL knowledge bases and mappings as bridge rules and individual correspondences. From the theoretical side, we study the task of reasoning with instance data in DDL composed of SHIQ ontologies and define a correct and complete distributed tableaux inference procedure. From the practical side, we upgrade the DRAGO DDL reasoner for dealing with instances and further show how it can be used to drive the migration of instances between heterogeneous ontologies.
26. Kernel Methods for Mining Instance Data in Ontologies , Stephan Bloehdorn and York Sure , 58-71 , [OpenAccess] , [Publisher]
    The amount of ontologies and meta data available on the Web is constantly growing. The successful application of machine learning techniques for learning of ontologies from textual data, i.e. mining for the Semantic Web, contributes to this trend. However, no principal approaches exist so far for mining from the Semantic Web. We investigate how machine learning algorithms can be made amenable for directly taking advantage of the rich knowledge expressed in ontologies and associated instance data. Kernel methods have been successfully employed in various learning tasks and provide a clean framework for interfacing between non-vectorial data and machine learning algorithms. In this spirit, we express the problem of mining instances in ontologies as the problem of defining valid corresponding kernels. We present a principled framework for designing such kernels by means of decomposing the kernel computation into specialized kernels for selected characteristics of an ontology which can be flexibly assembled and tuned. Initial experiments on real world Semantic Web data enjoy promising results and show the usefulness of our approach.
27. Lifecycle-Support in Architectures for Ontology-Based Information Systems , Thanh Tran,Peter Haase,Holger Lewen,Óscar Muñoz-García,Asunción Gómez-Pérez and Rudi Studer , 508-522 , [OpenAccess] , [Publisher]
    Ontology-based applications play an increasingly important role in the public and corporate Semantic Web. While today there exist a range of tools and technologies to support specific ontology engineering and management activities, architectural design guidelines for building ontology-based applications are missing. In this paper, we present an architecture for ontology-based application - covering the complete ontology-lifecycle - that is intended to support software engineers in designing and developing ontology-based applications. We illustrate the use of the architecture in a concrete case study using the NeOn toolkit as one implementation of the architecture.
28. Logical Foundations of (e)RDF(S): Complexity and Reasoning , Jos de Bruijn and Stijn Heymans , 86-99 , [OpenAccess] , [Publisher]
    An important open question in the semantic Web is the precise relationship between the RDF(S) semantics and the semantics of standard knowledge representation formalisms such as logic programming and description logics. In this paper we address this issue by considering embeddings of RDF and RDFS in logic. Using these embeddings, combined with existing results about various fragments of logic, we establish several novel complexity results. The embeddings we consider show how techniques from deductive databases and description logics can be used for reasoning with RDF(S). Finally, we consider querying RDF graphs and establish the data complexity of conjunctive querying for the various RDF entailment regimes.
29. Making More Wikipedians: Facilitating Semantics Reuse for Wikipedia Authoring , Linyun Fu,Haofen Wang,Haiping Zhu,Huajie Zhang,Yang Wang 0019 and Yong Yu , 128-141 , [OpenAccess] , [Publisher]
    Wikipedia, a killer application in Web 2.0, has embraced the power of collaborative editing to harness collective intelligence. It can also serve as an ideal Semantic Web data source due to its abundance, influence, high quality and well-structuring. However, the heavy burden of up-building and maintaining such an enormous and ever-growing online encyclopedic knowledge base still rests on a very small group of people. Many casual users may still feel difficulties in writing high quality Wikipedia articles. In this paper, we use RDF graphs to model the key elements in Wikipedia authoring, and propose an integrated solution to make Wikipedia authoring easier based on RDF graph matching, expecting making more Wikipedians. Our solution facilitates semantics reuse and provides users with: 1) a link suggestion module that suggests and auto-completes internal links between Wikipedia articles for the user; 2) a category suggestion module that helps the user place her articles in correct categories. A prototype system is implemented and experimental results show significant improvements over existing solutions to link and category suggestion tasks. The proposed enhancements can be applied to attract more contributors and relieve the burden of professional editors, thus enhancing the current Wikipedia to make it an even better Semantic Web data source.
30. Measuring Incoherence in Description Logic-Based Ontologies , Guilin Qi and Anthony Hunter , 381-394 , [OpenAccess] , [Publisher]
    Ontologies play a core role for the success of the Semantic Web as they provide a shared vocabulary for different resources and applications. Developing an error-free ontology is a difficult task. A common kind of error for an ontology is logical contradiction or incoherence. In this paper, we propose some approaches to measuring incoherence in DL-based ontologies. These measures give an ontology engineer important information for maintaining and evaluating ontologies. We implement the proposed approaches using the KAON2 reasoner and provide some preliminary but encouraging empirical results.
31. OBO and OWL: Leveraging Semantic Web Technologies for the Life Sciences , Christine Golbreich,Matthew Horridge,Ian Horrocks,Boris Motik and Rob Shearer , 169-182 , [OpenAccess] , [Publisher]
    OBO is an ontology language that has often been used for modeling ontologies in the life sciences. Its definition is relatively informal, so, in this paper, we provide a clear specification for OBO syntax and semantics via a mapping to OWL. This mapping also allows us to apply existing Semantic Web tools and techniques to OBO. We show that Semantic Web reasoners can be used to efficiently reason with OBO ontologies. Furthermore, we show that grounding the OBO language in formal semantics is useful for the ontology development process: using an OWL reasoner, we detected a likely modeling error in one OBO ontology.
32. On the Foundations of Computing Deltas Between RDF Models , Dimitris Zeginis,Yannis Tzitzikas and Vassilis Christophides , 637-651 , [OpenAccess] , [Publisher]
    The ability to compute the differences that exist between two RDF models is an important step to cope with the evolving nature of the Semantic Web (SW). In particular, RDF Deltas can be employed to reduce the amount of data that need to be exchanged and managed over the network and hence build advanced SW synchronization and versioning services. By considering Deltas as sets of change operations, in this paper we study various RDF comparison functions in conjunction with the semantics of the underlying change operations and formally analyze their possible combinations in terms of correctness, minimality, semantic identity and redundancy properties.
33. Ontology Performance Profiling and Model Examination: First Steps , Taowei David Wang and Bijan Parsia , 595-608 , [OpenAccess] , [Publisher]
    Reasoner performance can be scary, so much so, that we cannot deploy the technology in our products.
34. Ontology-Based Controlled Natural Language Editor Using CFG with Lexical Dependency , Hyun Namgoong and Hong-Gee Kim , 353-366 , [OpenAccess] , [Publisher]
    In recent years, CNL (Controlled Natural Language) has received much attention with regard to ontology-based knowledge acquisition systems. CNLs, as subsets of natural languages, can be useful for both humans and computers by eliminating ambiguity of natural languages. Our previous work, OntoPath, proposed to edit natural language-like narratives that are structured in RDF (Resource Description Framework) triples, using a domain-specific ontology as their language constituents. However, our previous work and other systems employing CFG for grammar definition have difficulties in enlarging the expression capacity. A newly developed editor, which we propose in this paper, permits grammar definitions through CFG-LD (Context-Free Grammar with Lexical Dependency) that includes sequential and semantic structures of the grammars. With CFG describing the sequential structure of grammar, lexical dependencies between sentence elements can be designated in the definition system. Through the defined grammars, the implemented editor guides users' narratives in more familiar expressions with a domain-specific ontology and translates the content into RDF triples.
35. Ontology-Based Interpretation of Keywords for Semantic Search , Thanh Tran,Philipp Cimiano,Sebastian Rudolph and Rudi Studer , 523-536 , [OpenAccess] , [Publisher]
    Current information retrieval (IR) approaches do not formally capture the explicit meaning of a keyword query but provide a comfortable way for the user to specify information needs on the basis of keywords. Ontology-based approaches allow for sophisticated semantic search but impose a query syntax more difficult to handle. In this paper, we present an approach for translating keyword queries to DL conjunctive queries using background knowledge available in ontologies. We present an implementation which shows that this interpretation of keywords can then be used for both exploration of asserted knowledge and for a semantics-based declarative query answering process. We also present an evaluation of our system and a discussion of the limitations of the approach with respect to our underlying assumptions which directly points to issues for future work.
36. PORE: Positive-Only Relation Extraction from Wikipedia Text , Gang Wang,Yong Yu and Haiping Zhu , 580-594 , [OpenAccess] , [Publisher]
    Extracting semantic relations is of great importance for the creation of the Semantic Web content. It is of great benefit to semi-automatically extract relations from the free text of Wikipedia using the structured content readily available in it. Pattern matching methods that employ information redundancy cannot work well since there is not much redundancy information in Wikipedia, compared to the Web. Multi-class classification methods are not reasonable since no classification of relation types is available in Wikipedia. In this paper, we propose PORE (Positive-Only Relation Extraction), for relation extraction from Wikipedia text. The core algorithm B-POL extends a state-of-the-art positive-only learning algorithm using bootstrapping, strong negative identification, and transductive inference to work with fewer positive training examples. We conducted experiments on several relations with different amount of training data. The experimental results show that B-POL can work effectively given only a small amount of positive training examples and it significantly outperforms the original positive learning approaches and a multi-class SVM. Furthermore, although PORE is applied in the context of Wikipedia, the core algorithm B-POL is a general approach for Ontology Population and can be adapted to other domains.
37. Potluck: Data Mash-Up Tool for Casual Users , David F. Huynh,Robert C. Miller and David R. Karger , 239-252 , [OpenAccess] , [Publisher]
    As more and more reusable structured data appears on the Web, casual users will want to take into their own hands the task of mashing up data rather than wait for mash-up sites to be built that address exactly their individually unique needs. In this paper, we present Potluck, a Web user interface that lets casual users –those without programming skills and data modeling expertise–mash up data themselves. Potluck is novel in its use of drag and drop for merging fields, its integration and extension of the faceted browsing paradigm for focusing on subsets of data to align, and its application of simultaneous editing for cleaning up data syntactically.Potluck also lets the user construct rich visualizations of data in-place as the user aligns and cleans up the data. This iterative process of integrating the data while constructing useful visualizations is desirable when the user is unfamiliar with the data at the beginning–a common case–and wishes to get immediate value out of the data without having to spend the overhead of completely and perfectly integrating the data first. A user study on Potluck indicated that it was usable and learnable, and elicited excitement from programmers who, even with their programming skills, previously had great difficulties performing data integration.
38. RDFSync: Efficient Remote Synchronization of RDF Models , Giovanni Tummarello,Christian Morbidoni,Reto Bachmann-Gmür and Orri Erling , 537-551 , [OpenAccess] , [Publisher]
    In this paper we describe RDFSync, a methodology for efficient synchronization and merging of RDF models. RDFSync is based on decomposing a model into Minimum Self-Contained graphs (MSGs). After illustrating theory and deriving properties of MSGs, we show how a RDF model can be represented by a list of hashes of such information fragments. The synchronization procedure here described is based on the evaluation and remote comparison of these ordered lists. Experimental results show that the algorithm provides very significant savings on network traffic compared to the file-oriented synchronization of serialized RDF graphs. Finally, we provide the design and report the implementation of a protocol for executing the RDFSync algorithm over HTTP.
39. SALT: Weaving the Claim Web , Tudor Groza,Knud Möller,Siegfried Handschuh,Diana Trif and Stefan Decker , 197-210 , [OpenAccess] , [Publisher]
    In this paper we present a solution for "weaving the claim web", i.e. the creation of knowledge networks via so-called claims stated in scientific publications created with the SALT (Semantically Annotated LaTeX) framework. To attain this objective, we provide support for claim identification, evolved the appropriate ontologies and defined a claim citation and reference mechanism. We also describe a prototypical claim search engine, which allows to reference to existing claims and hence, weave the web. Finally, we performed a small-scale evaluation of the authoring framework with a quite promising outcome.
40. SPARK: Adapting Keyword Query to Semantic Search , Qi Zhou,Chong Wang,Miao Xiong,Haofen Wang and Yong Yu , 694-707 , [OpenAccess] , [Publisher]
    Semantic search promises to provide more accurate result than present-day keyword search. However, progress with semantic search has been delayed due to the complexity of its query languages. In this paper, we explore a novel approach of adapting keywords to querying the semantic web: the approach automatically translates keyword queries into formal logic queries so that end users can use familiar keywords to perform semantic search. A prototype system named 'SPARK' has been implemented in light of this approach. Given a keyword query, SPARK outputs a ranked list of SPARQL queries as the translation result. The translation in SPARK consists of three major steps: term mapping, query graph construction and query ranking. Specifically, a probabilistic query ranking model is proposed to select the most likely SPARQL query. In the experiment, SPARK achieved an encouraging translation result.
41. Scalable Cleanup of Information Extraction Data Using Ontologies , Julian Dolby,James Fan,Achille Fokoue,Aditya Kalyanpur,Aaron Kershenbaum,Li Ma,J. William Murdock,Kavitha Srinivas and Christopher A. Welty , 100-113 , [OpenAccess] , [Publisher]
    The approach of using ontology reasoning to cleanse the output of information extraction tools was first articulated in SemantiClean. A limiting factor in applying this approach has been that ontology reasoning to find inconsistencies does not scale to the size of data produced by information extraction tools. In this paper, we describe techniques to scale inconsistency detection, and illustrate the use of our techniques to produce a consistent subset of a knowledge base with several thousand inconsistencies.
42. Semantic Cooperation and Knowledge Reuse by Using Autonomous Ontologies , Yuting Zhao,Kewen Wang,Rodney W. Topor,Jeff Z. Pan and Fausto Giunchiglia , 666-679 , [OpenAccess] , [Publisher]
    Several proposals have been put forward to support distributed agent cooperation in the Semantic Web, by allowing concepts and roles in one ontology be reused in another ontology. In general, these proposals reduce the autonomy of each ontology by defining the semantics of the ontology to depend on the semantics of the other ontologies. We propose a new framework for managing autonomy in a set of cooperating ontologies (or ontology space). In this framework, each language entity (concept/role/individual) in an ontology may have its meaning assigned either locally with respect to the semantics of its own ontology, to preserve the autonomy of the ontology, or globally with respect to the semantics of any neighbouring ontology in which it is defined, thus enabling semantic cooperation between multiple ontologies. In this way, each ontology has a "subjective semantics" based on local interpretation and a "foreign semantics" based on semantic binding to neighbouring ontologies. We study the properties of these two semantics and describe the conditions under which entailment and satisfiability are preserved. We also introduce two reasoning mechanisms under this framework: "cautious reasoning" and "brave reasoning". Cautious reasoning is done with respect to a local ontology and its neighbours (those ontologies in which its entities are defined); brave reasoning is done with respect to the transitive closure of this relationship. This framework is independent of ontology languages. As a case study, for Description Logic ALCN we present two tableau-based algorithms for performing each form of reasonings and prove their correctness.
43. Semplore: An IR Approach to Scalable Hybrid Query of Semantic Web Data , Lei Zhang,Qiaoling Liu,Jie Zhang,Haofen Wang,Yue Pan and Yong Yu , 652-665 , [OpenAccess] , [Publisher]
    As an extension to the current Web, Semantic Web will not only contain structured data with machine understandable semantics but also textual information. While structured queries can be used to find information more precisely on the Semantic Web, keyword searches are still needed to help exploit textual information. It thus becomes very important that we can combine precise structured queries with imprecise keyword searches to have a hybrid query capability. In addition, due to the huge volume of information on the Semantic Web, the hybrid query must be processed in a very scalable way. In this paper, we define such a hybrid query capability that combines unary tree-shaped structured queries with keyword searches. We show how existing information retrieval (IR) index structures and functions can be reused to index semantic web data and its textual information, and how the hybrid query is evaluated on the index structure using IR engines in an efficient and scalable manner. We implemented this IR approach in an engine called Semplore. Comprehensive experiments on its performance show that it is a promising approach. It leads us to believe that it may be possible to evolve current web search engines to query and search the Semantic Web. Finally, we breifly describe how Semplore is used for searching Wikipedia and an IBM customer's product information.
44. Sindice.com: Weaving the Open Linked Data , Giovanni Tummarello,Renaud Delbru and Eyal Oren , 552-565 , [OpenAccess] , [Publisher]
    Developers of SemanticWeb applications face a challenge with respect to the decentralised publication model: where to find statements about encountered resources. The "linked data" approach, which mandates that resource URIs should be de-referenced and yield metadata about the resource, helps but is only a partial solution and not followed widely. We present a lookup index over resources crawled on the Semantic Web. Our index allows applications to automatically retrieve sources with information about a certain resource. In contrast to more feature-rich Semantic Web search engines, our index is purposely limited in scope and functionality to achieve highly scalability and maintainability.
45. The Fundamentals of iSPARQL: A Virtual Triple Approach for Similarity-Based Semantic Web Tasks , Christoph Kiefer,Abraham Bernstein and Markus Stocker , 295-309 , [OpenAccess] , [Publisher]
    This research explores three SPARQL-based techniques to solve Semantic Web tasks that often require similarity measures, such as semantic data integration, ontology mapping, and Semantic Web service matchmaking. Our aim is to see how far it is possible to integrate customized similarity functions (CSF) into SPARQL to achieve good results for these tasks. Our first approach exploits virtual triples calling property functions to establish virtual relations among resources under comparison; the second approach uses extension functions to filter out resources that do not meet the requested similarity criteria; finally, our third technique applies new solution modifiers to post-process a SPARQL solution sequence. The semantics of the three approaches are formally elaborated and discussed. We close the paper with a demonstration of the usefulness of our iSPARQL framework in the context of a data integration and an ontology mapping experiment.
46. The Semantic Web and Human Inference: A Lesson from Cognitive Science , Takashi Yamauchi , 609-622 , [OpenAccess] , [Publisher]
    For the development of Semantic Web technology, researchers and developers in the Semantic Web community need to focus on the areas in which human reasoning is particularly difficult. Two studies in this paper demonstrate that people are predisposed to use class-inclusion labels for inductive judgments. This tendency appears to stem from a general characteristic of human reasoning - using heuristics to solve problems. The inference engines and interface designs that incorporate human reasoning need to integrate this general characteristic underlying human induction.
47. Using Tableau to Decide Expressive Description Logics with Role Negation , Renate A. Schmidt and Dmitry Tishkovsky , 438-451 , [OpenAccess] , [Publisher]
    This paper presents a tableau approach for deciding description logics outside the scope of OWL DL and current state-of-the-art tableau-based description logic systems. In particular, we define a sound and complete tableau calculus for the description logic ALBO and show that it provides a basis for decision procedures for this logic and numerous other description logics with full role negation. ALBO is the extension of ALC with the Boolean role operators, inverse of roles, domain and range restriction operators and it includes full support for objects (nominals). ALBO is a very expressive description logic which is NExpTime complete and subsumes Boolean modal logic and the two-variable fragment of first-order logic. An important novelty is the use of a versatile, unrestricted blocking rule as a replacement for standard loop checking mechanisms implemented in description logic systems. An implementation of our approach exists in the MetTeL system.
48. Web Search Personalization Via Social Bookmarking and Tagging , Michael G. Noll and Christoph Meinel , 367-380 , [OpenAccess] , [Publisher]
    In this paper, we present a new approach to web search personalization based on user collaboration and sharing of information about web documents. The proposed personalization technique separates data collection and user profiling from the information system whose contents and indexed documents are being searched for, i.e. the search engines, and uses social bookmarking and tagging to re-rank web search results. It is independent of the search engine being used, so users are free to choose the one they prefer, even if their favorite search engine does not natively support personalization. We show how to design and implement such a system in practice and investigate its feasibility and usefulness with large sets of real-word data and a user study.
49. YARS2: A Federated Repository for Querying Graph Structured Data from the Web , Andreas Harth,Jürgen Umbrich,Aidan Hogan and Stefan Decker , 211-224 , [OpenAccess] , [Publisher]
    We present the architecture of an end-to-end semantic search engine that uses a graph data model to enable interactive query answering over structured and interlinked data collected from many disparate sources on the Web. In particular, we study distributed indexing methods for graph-structured data and parallel query evaluation methods on a cluster of computers. We evaluate the system on a dataset with 430 million statements collected from the Web, and provide scale-up experiments on 7 billion synthetically generated statements.
50. combiSQORE: An Ontology Combination Algorithm , Rachanee Ungrangsi,Chutiporn Anutariya and Vilas Wuwongse , 566-579 , [OpenAccess] , [Publisher]
    Automatic knowledge reuse for Semantic Web applications imposes several challenges on ontology search. Existing ontology retrieval systems merely return a lengthy list of relevant single ontologies, which may not completely cover the specified user requirements. Therefore, there arises an increasing demand for a tool or algorithm with a mechanism to check concept adequacy of existing ontologies with respect to a user query, and then recommend a single or combination of ontologies which can entirely fulfill the requirements. Thus, this paper develops an algorithm, namely combiSQORE to determine whether the available collection of ontologies is able to completely satisfy a submitted query and return a single or combinative ontology that guarantees query coverage. In addition, it ranks the returned answers based on their conceptual closeness and query coverage. The experimental results show that the proposed algorithm is simple, efficient and effective.

Semantic Web Challenge Paper

1. CHIP Demonstrator: Semantics-Driven Recommendations and Museum Tour Generation , Lora Aroyo,Natalia Stash,Yiwen Wang,Peter Gorgels and Lloyd Rutledge , 879-886 , [OpenAccess] , [Publisher]
2. GroupMe! - Where Semantic Web Meets Web 2.0 , Fabian Abel,Mischa Frank,Nicola Henze,Daniel Krause,Daniel Plappert and Patrick Siehndel , 871-878 , [OpenAccess] , [Publisher]
3. Potluck: Semi-ontology Alignment for Casual Users , David F. Huynh,Robert C. Miller and David R. Karger , 903-910 , [OpenAccess] , [Publisher]
4. Revyu.com: A Reviewing and Rating Site for the Web of Data , Tom Heath and Enrico Motta , 895-902 , [OpenAccess] , [Publisher]
5. Semantics-Based Framework for Personalized Access to TV Content: The iFanzy Use Case , Pieter Bellekens,Lora Aroyo,Geert-Jan Houben,Annelies Kaptein and Kees van der Sluijs , 887-894 , [OpenAccess] , [Publisher]

Semantic Web In Use Track Paper

1. A Collaborative Semantic Web Layer to Enhance Legacy Systems , Alfio Massimiliano Gliozzo,Aldo Gangemi,Valentina Presutti,Elena Cardillo,Enrico Daga,Alberto Salvati and Gianluca Troiani , 764-777 , [OpenAccess] , [Publisher]
   This paper introduces a framework to add a semantic web layer to legacy organizational information, and describes its application to the use case provided by the Italian National Research Council (CNR) intraweb. Building on a traditional web-based view of information from different legacy databases, we have performed a semantic porting of data into a knowledge base, dependent on an OWL domain ontology. We have enriched the knowledge base by means of text mining techniques, in order to discover on-topic relations. Several reasoning techniques have been applied, in order to infer relevant implicit relationships. Finally, the ontology and the knowledge base have been deployed on a semantic wiki by means of the WikiFactory tool, which allows users to browse the ontology and the knowledge base, to introduce new relations, to revise wrong assertions in a collaborative way, and to perform semantic queries. In our experiments, we have been able to easily implement several functionalities, such as expert finding, by simply formulating ad-hoc queries from either an ontology editor or the semantic wiki interface. The result is an intelligent and collaborative front end, which allow users to add information, fill gaps, or revise existing information on a semantic basis, while keeping the knowledge base automatically updated.
2. A Semantic Case-Based Reasoning Framework for Text Categorization , Valentina Ceausu and Sylvie Desprès , 736-749 , [OpenAccess] , [Publisher]
   This paper presents a semantic case-based reasoning framework for text categorization. Text categorization is the task of classifying text documents under predened categories. Accidentology is our application eld and the goal of our framework is to classify documents describing real road accidents under predened road accident prototpypes, which also are described by text documents. Accidents are described by accident reports while accident prototypes are described by accident scenarios. Thus, text categorization is done by assigning each accident report to an accident scenario, which highlights particular mechanisms leading to accident. We propose a textual case based reasoning approach (TCBR), which allows us to integrate both textual and domain knowledge aspects inorder to carry out this categorization. CBR solves a new problem (target case) by identifying its similarity to one or several previously solved problems (source cases) stored in a case base and by adapting their known solutions. Cases of our framework are created from text. Most of TCBR applications create cases from text by using Information Retrieval techniques, which leads to knowledge-poor descriptions of cases. We show that using semantic resources (two ontology of accidentology) makes possible to overcome this diculty, and allows us to enrich cases by using formal knowledge. In this paper, we argue that semantic resources are likely to improve the quality of cases created from text, and, therefore, such resources can support the reasoning cycle. We illustrate this claim with our framework developed to classify documents in the accidentology domain.
3. Application of Ontology Translation , James Ressler,Mike Dean,Edward Benson,Eric Dorner and Chuck Morris , 830-842 , [OpenAccess] , [Publisher]
   An ontology provides a precise specification of the vocabulary used by a community of interest (COI). Multiple communities of interest may describe the same concept using the same or different terms. When such communities interact, ontology alignment and translation is required. This is typically a time consuming process. This paper describes Snoggle, an open source tool designed to ease development of ontology translation rules, and discusses its application to geospatial ontologies.
4. DBpedia: A Nucleus for a Web of Open Data , Sören Auer,Christian Bizer,Georgi Kobilarov,Jens Lehmann,Richard Cyganiak and Zachary G. Ives , 722-735 , [OpenAccess] , [Publisher]
   DBpedia is a community effort to extract structured information from Wikipedia and to make this information available on the Web. DBpedia allows you to ask sophisticated queries against datasets derived from Wikipedia and to link other datasets on the Web to Wikipedia data. We describe the extraction of the DBpedia datasets, and how the resulting information can be made available on the Web for humans and machines. We describe some emerging applications from the DBpedia community and show how website operators can reduce costs by facilitating royalty-free DBpedia content within their sites. Finally, we present the current status of interlinking DBpedia with other open datasets on the Web and outline how DBpedia could serve as a nucleus for an emerging Web of open data sources.
5. EIAW: Towards a Business-Friendly Data Warehouse Using Semantic Web Technologies , Guo Tong Xie,Yang Yang,Shengping Liu,Zhaoming Qiu,Yue Pan and Xiongzhi Zhou , 857-870 , [OpenAccess] , [Publisher]
   Data warehouse is now widely used in business analysis and decision making processes. To adapt the rapidly changing business environment, we develop a tool to make data warehouses more business-friendly by using Semantic Web technologies. The main idea is to make business semantics explicit by uniformly representing the business metadata (i.e. conceptual enterprise data model and multidimensional model) with an extended OWL language. Then a mapping from the business metadata to the schema of the data warehouse is built. When an analysis request is raised, a customized data mart with data populated from the data warehouse can be automatically generated with the help of this built-in knowledge. This tool, called Enterprise Information Asset Workbench (EIAW), is deployed at the Taikang Life Insurance Company, one of the top five insurance companies of China. User feedback shows that OWL provides an excellent basis for the representation of business semantics in data warehouse, but many necessary extensions are also needed in the real application. The user also deemed this tool very helpful because of its flexibility and speeding up data mart deployment in face of business changes.
6. HealthFinland - Finnish Health Information on the Semantic Web , Eero Hyvönen,Kim Viljanen and Osma Suominen , 778-791 , [OpenAccess] , [Publisher]
   This paper shows how semantic web techniques can be applied to solving problems of distributed content creation, discovery, linking, aggregation, and reuse in health information portals, both from end-user's and content publishers's viewpoints. As a case study, the national semantic health portal HEALTHFINLAND is presented. It provides citizens with intelligent searching and browsing services to reliable and up-to-date health information created by various health organizations in Finland. The system is based on a shared semantic metadata schema, ontologies, and mash-up ontology services. The content includes metadata of thousands of web documents such as web pages, articles, reports, campaign information, news, services, and other information related to health.
7. Matching Patient Records to Clinical Trials Using Ontologies , Chintan Patel,James J. Cimino,Julian Dolby,Achille Fokoue,Aditya Kalyanpur,Aaron Kershenbaum,Li Ma,Edith Schonberg and Kavitha Srinivas , 816-829 , [OpenAccess] , [Publisher]
   This paper describes a large case study that explores the applicability of ontology reasoning to problems in the medical domain. We investigate whether it is possible to use such reasoning to automate common clinical tasks that are currently labor intensive and error prone, and focus our case study on improving cohort selection for clinical trials. An obstacle to automating such clinical tasks is the need to bridge the semantic gulf between raw patient data, such as laboratory tests or specific medications, and the way a clinician interprets this data. Our key insight is that matching patients to clinical trials can be formulated as a problem of semantic retrieval. We describe the technical challenges to building a realistic case study, which include problems related to scalability, the integration of large ontologies, and dealing with noisy, inconsistent data. Our solution is based on the SNOMED CT ontology, and scales to one year of patient records (approx. 240,000 patients).
8. Ontology-Based Information Extraction for Business Intelligence , Horacio Saggion,Adam Funk,Diana Maynard and Kalina Bontcheva , 843-856 , [OpenAccess] , [Publisher]
   Business Intelligence (BI) requires the acquisition and aggregation of key pieces of knowledge from multiple sources in order to provide valuable information to customers or feed statistical BI models and tools. The massive amount of information available to business analysts makes information extraction and other natural language processing tools key enablers for the acquisition and use of that semantic information. We describe the application of ontology-based extraction and merging in the context of a practical e-business application for the EU MUSING Project where the goal is to gather international company intelligence and country/region information. The results of our experiments so far are very promising and we are now in the process of bulding a complete end-to-end solution.
9. Purpose-Aware Reasoning about Interoperability of Heterogeneous Training Systems , Daniel Elenius,Reginald Ford,Grit Denker,David Martin and Mark Johnson , 750-763 , [OpenAccess] , [Publisher]
   We describe a novel approach by which software can assess the ability of a confederation of heterogeneous systems to interoperate to achieve a given purpose. The approach uses ontologies and knowledge bases (KBs) to capture the salient characteristics of systems, on the one hand, and of tasks for which these systems will be employed, on the other. Rules are used to represent the conditions under whichthe capabilities provided by systems can fulfill the capabilities needed to support the roles and interactions that make up each task. An Analyzer component employs these KBs and rules to determine if a given confederation will be adequate, to generate suitable confederations from a collection of available systems, to pre-diagnose potential interoperability problems that might arise, and to suggest system configuration options that will help to make interoperability possible. We have demonstrated the feasibility of this approach using a prototype Analyzer and KBs.
10. Recipes for Semantic Web Dog Food - The ESWC and ISWC Metadata Projects , Knud Möller,Tom Heath,Siegfried Handschuh and John Domingue , 802-815 , [OpenAccess] , [Publisher]
    Semantic Web conferences such as ESWC and ISWC offer prime opportunities to test and showcase semantic technologies. Conference metadata about people, papers and talks is diverse in nature and neither too small to be uninteresting or too big to be unmanageable. Many metadata-related challenges that may arise in the Semantic Web at large are also present here. Metadata must be generated from sources which are often unstructured and hard to process, and may originate from many different players, therefore suitable workflows must be established. Moreover, the generated metadata must use appropriate formats and vocabularies, and be served in a way that is consistent with the principles of linked data. This paper reports on the metadata efforts from ESWC and ISWC, identifies specific issues and barriers encountered during the projects, and discusses how these were approached. Recommendations are made as to how these may be addressed in the future, and we discuss how these solutions may generalize to metadata production for the Semantic Web at large.
11. Spatially-Augmented Knowledgebase , Dave Kolas and Troy Self , 792-801 , [OpenAccess] , [Publisher]
    As an increasing number of applications on the web contain some elements of spatial data, there is a need to efficiently integrate Semantic Web technologies and spatial data processing. This paper describes a prototype system for storing spatial data and Semantic Web data together in a SPatially-AUgmented Knowledgebase (SPAUK) without sacrificing query efficiency. The goals are motivated through use several use cases. The prototype's design and architec-ture are described, and resulting performance improvements are discussed.
12. Unlocking the Potential of Public Sector Information with Semantic Web Technology , Harith Alani,David Dupplaw,John Sheridan,Kieron O'Hara,John Darlington,Nigel Shadbolt and Carol Tullo , 708-721 , [OpenAccess] , [Publisher]
    Governments often hold very rich data and whilst much of this information is published and available for re-use by others, it is often trapped by poor data structures, locked up in legacy data formats or in fragmented databases. One of the great benefits that Semantic Web (SW) technology offers is facilitating the large scale integration and sharing of distributed data sources. At the heart of information policy in the UK, the Office of Public Sector Information (OPSI) is the part of the UK government charged with enabling the greater re-use of public sector information. This paper describes the actions, findings, and lessons learnt from a pilot study, involving several parts of government and the public sector. The aim was to show to government how they can adopt SW technology for the dissemination, sharing and use of its data.

Proceedings of ISWC 2007 Poster and Demo

1. A Domain Ontology Construction Method Supported by an Ontology Search Engine , Takeshi Morita,Takuya Tejima,Noriaki Izumi and Takahira Yamaguchi
   In order to reduce the cost of building domain ontologies manually, in this paper, we integrate a domain ontology development environment: DODDLE-OWL and an ontology search engine: Swoogle. We propose a method and a tool for domain ontology construction reusing texts and existing ontologies for a target domain extracted by Swoogle. In the evaluation, we applied the method to a particular field of law and evaluated the acquired ontologies.
2. A Goal-Based Semantic Web Service Browser , Michael Stollberg,Mick Kerrigan and Martin Hepp
   We present a novel approach for the visualization and browsing of Web services. In contrast to most existing tools that categorize Web service with respect to specific description elements, our tool is based on goals that describe the objective that a client wants to solve by using Web services while abstracting from the technical details. The data structure for our search space visualization is a graph that organizes goal templates - i.e. generic and reusable objective descriptions - with respect to their semantic similarity, and keeps the relevant knowledge on the available Web services for solving them; the graph is generated automatically by semantic matchmaking. The browsing tool is implemented as a new plug-in of the Web Service Modeling Toolkit WSMT, an integrated development environment for Semantic Web services.
3. A Health Advice Derivation System based on an Ontology , Satoru Izumi,Naofumi Yasuda,Goichi Itabashi,Yasushi Kato,Kaoru Takahashi,Takuo Suganuma and Norio Shiratori
   This paper presents a health advice derivation system. The system can derive adequate advices according to user's goal and the health condition of the user because an ontology is introduced into the system for describing the knowledge about exercise, meal and user's health condition. We introduce an inference mechanism into the system for deriving advices because the inference mechanism makes good use of the ontology. New relationships on the knowledge are found by the inference mechanism and are finally provided as advices to the user.
4. A Semantic Portal for Researchers Using OntoFrame , Won-Kyung Sung,Hanmin Jung,Pyung Kim,In-Su Kang,Seung-Woo Lee,Mi-Kyung Lee,Dong-In Park and Sun-Hwa Hahn
   To help researchers to get information, we build a semantic portal using OntoFrame, KISTI's semantic web platform. Unlike other semantic web solutions, URI-server underlies OntoFrame. It stores ontology instances before populating them into a triple store, controlling their key/referential integrities based on URI. Our semantic portal is thus efficiently maintained by assigning search-oriented requests to URI-server-based IR engine and reasoning queries to the inference system.
5. A Statistical Approach for Semantic Search using Heterogenous Semantics on the Web , Rui Huang and Zhongzhi Shi
   For relevance ranking in Web search, heterogeneous semantic information such as thesauruses, semantic markups and social annotations have been adopted respectively. As utilization of semantics are key to semantic search, to integrate more semantics would logically generate better search results in respect of semantic relevance. However, such integrated semantic search mechanism is still in absence and to be developed. This paper proposes a statistical approach to integrate both keywords and heterogeneous semantics for semantic search.
6. An Ontology Service for Geographical Content , Eero Hyvönen,Robin Lindroos,Tomi Kauppinen and Riikka Henriksson
   Geographic place names are widely used but are semantically often highly ambiguous. For example, there are 491 places in Finland sharing the same name "Isosaari" (great island) that are instances of several geographical classes, such as Island, Forest, Peninsula, Inhabited area, etc. Referencing unambiguously to a particular "Isosaari", either when annotating content or during information retrieval, can be quite problematic and requires usage of advanced search methods and maps for semantic disambiguation. This paper presents an ontology server, ONKI-Paikka, for solving the place finding and place name disambiguation problem. In ONKI-Paikka, places can be found by a faceted search engine, combined with semantic autocompletion and a map service for constraining search and for visualizing results. The service can be connected to legacy applications cost-effectively by using Ajax-technology in the same spirit as Google Maps that is used in ONKI-Paikka as a subservice.
7. ArnetMiner: Extraction and Mining of an Academic Researcher Social Network , Jie Tang,Jing Zhang,Duo Zhang and Limin Yao
   This demonstration aims at presenting an overview of the ArnetMiner system. The system addresses several key issues in extraction and mining of the researcher social network. The system is in operation on the internet for about one year and receives accesses from about 1,500 users per month. Feedbacks from users and system logs indicate that users consider the system can help people to find and share information in the web community.
8. Automatic Exhibition Generation Based on Semantic Cultural Content , Eetu Mäkelä,Tuukka Ruotsalo and Eero Hyvönen
   This paper shortly presents an automatic exhibition generation interface that turns the focus of semantic search from search items to the concepts they are annotated with.
9. Building the bases for a Semantic Web Browser , Davide Guidi,Laurian Gridinoc,Martin Dzbor and Enrico Motta
   In this paper we describe the first results of our efforts to build a solid framework for a Semantic Web browser, Power Magpie. For Semantic Web browser we envision an extension to a standard Web browser that augment its features with the ability to act on resources described in Web pages and to find resources semantically related to a Web page. In our vision, the Power Magpie prototype will provide three main features: 1. The ability to automatically find and retrieve ontologies that are related to the generic Web page that the user is browsing. 2. A simple user interface to navigate these data (as well as the Semantic data available in the Web page itself, using technologies such as RDFa or Microformats). 3. The ability to provide services that exploit the discovered data. The current state of the prototype already address the first two points, while the latter can be considered a further step that can be develop upon the proposed framework.
10. Can Inconsistent Reasoning Be Complete? , Mauro Mazzieri and Aldo Franco Dragoni
    As classical reasoning from inconsistent ontologies can't give meaningful answers to queries, it is necessary to either revise the ontology, discarding some axioms in order to restore consistency, or make use of a non-standard notion of logical entailment that allows to give meaningful answers from inconsistent premises. We propose a complete procedure to reason with inconsistent ontologies and show how ontology revision can be obtained from inconsistency reasoning.
11. Clustering of Wikipedia Terms with Paradigmatic Relations for Building Domain Ontology , Chungwon Seo and Key-Sun Choi
    For building ontology from text, we need to extract terms and conceptualize them as classes of ontology. In this paper we present a clustering of terms method using paradigmatic relation and hierarchical clustering. To extract the paradigmatic relation, we use 1st and 2nd order collocation extracted from Wikipedia documents. By computing the semantic relatedness of clusters, we can extract clusters that consist of similar words.
12. Combining Cross-ontology Navigation with Semantic Autocompletion , Eetu Mäkelä,Tuukka Ruotsalo and Eero Hyvönen
    Semantic autocompletion interfaces offer an efficient way for concept selection useful in both search and annotation applications. However, these interfaces usually do not expose the semantic context of the matched concepts, thereby making it hard to know if a matched concept is the right one, as well as hiding possibly more appropriate choices. To lessen these problems, we present an in-place ontological context navigation interface to be used with semantic autocompletion.
13. Correspondence Patterns for Ontology Mediation , François Scharffe,Jérôme Euzenat,Ying Ding and Dieter Fensel
    Ontology mediation is one of the key research topics for the acomplishment of the semantic web. Different tasks can be distinguished under this generic term: instance transformation, query rewriting, instance unification, ontology merging or alignment creation. All first four tasks require the specification of an alignment between the ontologies to be mediated. Graphical tools and matching algorithms are developed to help specialists creating such specifications. In order to improve both user tools and matching algorithms we developped a library of correspondence patterns to represent complex correspondences between ontologies. We express these patterns as an extension of the Ontology Alignment ontology, meant to serve as an exchange format to represent ontology alignments on the semantic web.
14. Creating Metadata for a Semantic Web Health Portal , Osma Suominen,Kim Viljanen and Eero Hyvönen
    We present an overview of the infrastructure required to support content and metadata creation for a health portal based on Semantic Web technologies. The system requires web content management systems to be enhanced to support ontological metadata creation; export of metadata in RDF or embedded into HTML pages; and a metadata harvester that aggregates metadata from all the content creators and provides feedback reports to the content creators. The system has been set up in a prototype of the national health portal HEALTHFINLAND.
15. Domain-Centric View-Based Search , Eetu Mäkelä,Tuukka Ruotsalo and Eero Hyvönen
    In current Semantic Web view-based search systems views are formed by selecting properties and enumerating all their values as selections. This approach breaks down with multiple content types, such as in the cultural heritage domain, because the number of differing properties, and therefore views becomes unmanageable. We propose a novel solution termed Domain-Centric View-Based Search, in which views are created based on common property ranges and domain ontologies.
16. Dynamic Horizontal Composition for Semantic Web Services: An Investigation of Real Use , Ahlem Ben Hassine,Shigeo Matsubara and Toru Ishida
    We propose a new dynamic constraint optimization problem (COP) formalization for Web services composition problem that permits extension of the original abstract workflow (in case failure) based on the OWL-S service profile description of the underlying semantic Web services and using OWL-S control constructs. Moreover, we have developed a novel, human-centered, agent-based protocol able to find "satisfying" solutions for this problem in real time. This protocol allows restriction and/or relaxation within the original workflow through addition and/or removal of new sub-tasks, deals with a dynamic environment, and uses incomplete, uncertain information.
17. EASAIER: Semantic Music Retrieval Portal , Michael Luger,Ying Ding,Zhixian Yan,François Scharffe,Yubin Duan,Yves Raimond,Luc Barthelemy and Josh Reiss
    Semantic Web aims to lift current Web into semantic repositories where heterogeneous data can be queried and different services can be mashed up. Here we report some of on-going work with the EASAIER project to enable enhanced access to sound archives by integrating archives based on Music Ontology and provide different search results from different mashups.
18. Expertise Object Search , Jie Tang
    This paper addresses the issue of expertise object search. In Semantic Web, information is described as concepts and relations between the concepts. Previous document-level information search can unfortunately lead to highly inaccurate results in answering semantic-oriented queries. Previous work on semantic search is targeted at finding the most relevant objects. In this paper, we investigate several models for expertise object search, namely local language model, propagation based model, and a unified model.
19. Extending Content Management Systems with Ontological Annotation Capabilities , Kim Viljanen,Jouni Tuominen,Eero Hyvönen,Eetu Mäkelä and Osma Suominen
    Producing semantic metadata requires efficient methods, e.g., concept finding, for accessing and using ontologies. To add such functionalities to metadata applications such as cataloging systems in museums, we propose a mash-up approach where ready-to-use user interface components for using specific ontologies are made available to be integrated into applications. As a proof-of-concept, we present the Ontology Service ONKI wich implements semantic autocompletion concept search and concept browsing for ontologies as shared mash-up components.
20. Extracting and Utilizing Event-Context Relationships in Blogsphere , Yukino Baba,Fuyuki Ishikawa and Shinichi Honiden
    A keyword-based web search cannot accept a user's detailed intention for a search. Consideration has been made concerning the annotation of context data (e.g. contents creation time and location) for a web search in response to this problem. However, it would require users to handle accurate context data in search queries. This paper proposes a method to associate keywords with context data by analyzing blog entries annotated with context data, including an efficient mechanism for indexing.
21. HOMER: Ontology alignment visualization and analysis , Octavian Udrea,Lise Getoor and Renée J. Miller
    We present HOMER, an analysis and visualization tool for ontology alignment. HOMER features a radial-graph display GUI, a complete execution trace that allows the user to override and navigate to any match decisions during at runtime and a comparison mode that displays multiple alignments in parallel. HOMER contains a builtin plugin for the ILIADS ontology alignment algorithm, but other algorithms can be plugged in as well.
22. Hawkeye: A Practical Large Scale Demonstration of Semantic Web Integration , Zhengxiang Pan,Abir Qasem,Sudhan Kanitkar,Fabiana Prabhakar and Jeff Heflin
    We present our DLDB knowledge base system and evaluate its capability in integrating a very large set of real-world Semantic Web data. Using DLDB, we have constructed the Hawkeye knowledge base, in which we have loaded more than 166 million facts from a diverse set of real-world data sources and integrated them using alignments expressed in OWL.
23. Human Resource Management System introducing Healthcare of Employee , Daisuke Noheji,Goichi Itabashi,Toshiko Yoshida and Atsushi Togashi
    Human Resource Management (HRM) aims a strategic human resource administration in a company organization. In order to support HRM, various information systems have been developed conventionally. They are used for management of personal information, ability evaluation, and employee education. By introducing HRM, a company can develop employees and allocate them into adequate position. However, when an employee leaves him/her job due to a problem of the health, the effect of HRM may be reduced. Therefore, a productivity of a whole organization may be also reduced. We assume that there exists strong relevance in HRM and the health of the employee and develop Healthy Human Resource Management (H2RM) system. This system offers a recommendation of health education contents that is included in H2RM system. The recommendation is derived by an inference system based on an ontology and inference rule about health and disease. By using the inference system, the health condition of an employee is decided according to their health condition. Then the system offers the recommendation of healthcare education contents.
24. Integrating Relations for a Domain Ontology , Jin-Xia Huang,Ji-Ae Shin and Key-Sun Choi
    This paper addresses an approach for building a relation hierarchy in order to integrate relations from different sources. A relation tree is generated by mapping relations to WordNet synsets, on which duplicated relations are eliminated. As criteria for judging relations not absolutely required for a domain, popularity and uniqueness are proposed. Our research shows that use of a relation hierarchy makes the process of judging necessary relations of a domain much simpler and more efficient.
25. Light-Weight Semantic Desktop Applications , Knud Möller
    Since Vannevar Bush's vision of the Memex, the idea of a knowledge working environment with interlinked data has been around. Recently, with a significant increase in computing power and the advent of the Semantic Web, these ideas have surfaced again, now under the term "Semantic Desktop". Many attempts to build such a Semantic Desktop try to build a complete system from scratch. In this demo, we want to show that it is also possible to get a long way with existing OS technology, which will simply be harnessed in the form of a number of small, lightweight tools. Instead of building an extensive and feature-rich system from scratch, we harness the power of modern, metadata-enabled file systems and search indices to create a prototypical system with minimal effort.
26. Minimum Expression Axiom Set (MEXS) Extracting and Storing for Ontology Debugging , Je-Min Kim and Young-Tack Park
    In order to derive hidden information of OWL ontology, a number of OWL reasoners have been introduced. In this paper, we propose MEXS (Minimum Expression Axiom Set) extracting and storing for debugging unsatisfiable concepts in ontology. A MEXS is a set of axioms to occur unsatisfiable concepts. In order to extract MEXS, we need to find axiom to cause inconsistency in ontology. Therefore we propose an improved method.
27. OOPS: User Modeling Method toward Realization of Task Oriented Mobile Internet Service Navigation , Munehiko Sasajima,Yoshinobu Kitamura,Takefumi Naganuma,Shoji Kurakake and Riichiro Mizoguchi
    Remarkable growth of the mobile internet service industry in Japan proved that present method of service menu system is insufficient to guide users efficiently to the services they need. This paper introduces our research activities toward realization of Task-oriented menu system, which enables users to search for mobile services by "what they want to do" instead of by "name of category". Although efficiency of the menu system has been proved on a prototype system, it is limited and capable of supporting limited activities; mobile users' activity in a theme park. Thus we need to analyze wider area of user activities to list up the situations and task models of users as many as possible to expand the prototype menu to cover larger scale of the services. We introduce OOPS (Ontology-based Obstacle, Prevention and Solution) modeling method which supports description of the necessary situations. We have applied the method to model "Tourism" domain which covers a broader spectrum of users' actions. We have evaluated the coverage of the OOPS model by verifying situations represented in the model developed and those situations assumed to be supported by i-mode official services. The model covered about 97% of the assumed situations of mobile internet services. Reorganizing "contexts" in the model, we aim at developing task oriented menu system as a next step.
28. OPTIMA: A System for Semi Automatic and Large Scale Ontology Population , Ivan Berlocher,Hyun-Geun Park,Ki-Un Cho and Kwang-Seun Choi
    In this paper we describes OPTIMA (Ontology Population Tool based on Information extraction and MAtching) a system for semiautomatically populating ontologies from unstructured and semi-structured information. Based on Information Extraction techniques the system identifies Named Entities and their inter-relations that serve as basis of a Machine Learning algorithm for generating candidates of instances according to classes described in the ontology schema, associated with a probability score.
29. OWL Full Metamodeling with SWCLOS , Seiji Koide and Hideaki Takeda
    SWCLOS is an OWL Full processor buit on top of Common Lisp Object System. We enabled OWL metamodeling with SWCLOS. In this poster and demo, we introduce criteria for metamodeling, that are derived from the principles of object-oriented metamodeling, and demonstrate examples of metamodeling with SWCLOS.
30. Okkam4P: A Protégé Plugin for Instance-level Integration of RDF Content , Paolo Bouquet,Daniel Giacomuzzi,Heiko Stoermer and Daniele Zanoni
    In Protege, any newly created RDF/OWL knowledge base refers to local instances through a local URI, which is obtained through the concatenation of the ontology URI, the hash sign '#' and the local identifier. However, this practice makes data level integration quite hard, and definitely prevents the straightforward application of RDF graph merge for independently developed knowledge bases, even if they share the same OWL ontology. In this paper, we present a Protege plugin which supports the systematic reuse of global identifiers for instances in RDF/OWL knowledge base. The plugin is an extension of the "individual" tab. The main difference is that, when an instance is created, the user has a chance of looking for a pre-existing URI for the corresponding individual in a publicly available service called OKKAM. The match between the newly created instance and the stored individuals is based on an algorithm which compares the features of the new isntance with a simple profile stored in OKKAM for all individuals. The plugin is available and tested for Protege 3.2.1.
31. OnCU System: Ontology-based Category Utility Approach for Author Name Disambiguation , Young-Tack Park,Je-Min Kim,Jung-Hwa Choi and Bo-Ram Han
    This paper introduces a novel approach which exploits ontologies and ontology-based category utility for author name disambiguation. Our method utilizes author knowledge in the form of populated ontology that uses various types of properties: titles, abstracts and co-authors of papers and authors' affiliations. Author name disambiguation determines the correct author from various candidate authors in the populated author ontology. Candidate authors are evaluated using proposed ontology-based category utility to resolve disambiguation. Experiments using the ontology-based category utility increase the number of disambiguation by about 10% compared with that of category utility, and increase the overall amount of accuracy by around 98%.
32. OntoGame: Turning Ontology Engineering into an Online Game with a Purpose , Katharina Siorpaes and Martin Hepp
    Despite significant advancement in ontology learning, building ontologies remains a task that highly depends on human intelligence, both as a source of domain expertise and for producing a consensual conceptualization. Now, we can observe a sharp contrast in user interest in two branches of Web activity: While the "Web 2.0" movement lives from an unprecedented amount of contributions from Web users, we witness a substantial lack of user involvement in ontology projects for the Semantic Web. We assume that one cause of the latter is a lack of proper incentive structures of ontology projects. As a novel solution, we (1) propose to masquerade collaborative ontology engineering behind on-line, multi-player game scenarios, in order to create proper incentives for humans to help building ontologies for the Semantic Web. Then, we (2) describe our OntoGame prototype, and (3) provide preliminary evidence that users are willing to invest a lot of time into those games, and, by doing so, unknowingly weave ontologies for the Semantic Web.
33. OntoMinD: Ontology Management in Databases , Lina Al-Jadir,Othman Tajmouati,Christine Parent and Stefano Spaccapietra
    A current major obstacle to the development of ontologies in support of the Semantic Web is the inability to handle very large ontologies. We propose a solution which consists in augmenting the functionality of a relational DBMS to include the reasoning mechanisms (implemented as stored procedures) that are the essence of ontology management. As a result, a single system is used to store, query, update, and reason about a very large ontology. The OntoMinD prototype we have developed shows very promising performances, according to our tests with the LUBM benchmark.
34. Ontology Merging using Answer Set Programming and Linguistic Knowledge , Jürgen Bock,Rodney Topor and Raphael Volz
    We present a novel merging algorithm for light-weight ontologies using answer set programming and linguistic background knowledge. The semi-automatic method provides a number of solutions for the user to choose from, by straightforwardly applying intuitive merging rules in a declarative programming environment.
35. Ontology Revision Without Priority to Incoming Information , Mauro Mazzieri and Aldo Franco Dragoni
    Ontology evolution is the process of modifying an ontology to preserve consistency during changes. Current work on ontology evolution is based on the idea of bringing the AGM belief change theory to work within ontology evolution. However, AGM's principle of priority to incoming information can not be accepted when the new information represents a new evidence about the world, supposed to be a fixed static entity, while its description is only partial and uncertain. In particular, it can not be accepted in a distributed environment, where the information sources are potentially unreliable. We replace the priority to incoming information with the principle of recoverability: any previously held piece of knowledge should belong to the current knowledge space if consistent with it.
36. Ontology-based Named Entity Disambiguation in Automatic Semantic Annotation , Jung-Hwa Choi and Young-Tack Park
    The vision of Semantic Web can be realized when there are masses of machine-processable semantic metadata. Manual construction of metadata is not feasible, methods for automated semantic annotation have been developed. Semantic annotation is the process to identify the most appropriate semantic tagging to entities. The key challenge in automatic semantic annotation is resolving ambiguities in identifying semantic tagging. We propose the ontology-based semantic named entity disambiguation, which is a new named entity disambiguation algorithm, based on Hidden Markov Model (HMM) and semantic contexts. Based on our system, ubiquitous applications can reason about named entity free of contradictions. Compared to SemTag algorithm, our system has an improved performance by about 18%.
37. Ontology-based Question Answering System , Sheen-Mok Lee,Pummo Ryu and Key-Sun Choi
    In this paper, we construct IT-domain question-answering system as an application system of the IT-domain ontology. We defined 16 types of questions based on question type definition by DARPA. For each of the question type, an inferencing method is designed and implemented. We demonstrate the user interface which can connect users with the QA system and the ontology.
38. Ontology-based Semantic Context Modeling for Invisible Object Recognition , Jung-Hwa Choi,Young-Tack Park and Il Hong Suh
    Object recognitions are challenging tasks, especially invisible object recognition in changing and unpredictable robot environments. We propose a novel approach employing context and ontology to improve object recognition capability of mobile robots in real-world situations. By semantic contexts we mean characteristic information abstracted from robot sensors. We propose a method to construct semantic contexts using inferences for mobile robots to recognize objects in a more efficient way. In addition, ontology has been used for better recognizing objects using knowledge represented in the ontology.
39. Product and process modelling standards on the Web , David Leal and Michel Böhms
    The poster describes the current status of the international effort to transform existing international standards so that they can work as part of the Semantic Web. There are different standards for mechanical products, building and construction and process plants, but these have similar requirements for the representation of product structure. The definition of a common core ontology for product structure is being attempted.
40. Question Answering on the Real Semantic Web , Vanessa López,Miriam Fernández,Enrico Motta,Marta Sabou and Victoria Uren
    Restriction to a predefined set of ontologies, and consequently limitation to specific domain environments is a pervading drawback in Semantic Search technologies. In this work we present PowerAqua, a multi-ontology-based Question Answering (QA) platform that exploits multiple distributed ontologies and knowledge bases to answer queries in multi-domain environments. The system interprets the user's Natural Language (NL) query using the available semantic information, and translates the user terminology into the ontology terminology (triples), retrieving accurate semantic entity values as response to the user's request.
41. Relational Semantic Search: Searching Social Paths on the Semantic Web , Jussi Kurki and Eero Hyvönen
    This paper presents a system for searching semantic relations between web resources, in our case significant persons of art history. The system is based on the Union List of Artists Names (ULAN) metadata of some 120,000 persons and organizations.
42. Research on Ontology Developing Methodology and System , Li Jing,Meng Xian-Xue and Su Xiao-Lu
    We try to develop a methodology, as a system of discipline and a number of tools to help create useful ontologies. Our methodology and system lends concepts and practices from software development, and improve them to fit some special requirements of knowledge development.
43. Retrieval Optimization of Pertinent Answers for NL Questions with the E-Librarian Service , Serge Linckels,Harald Sack and Christoph Meinel
    Video recordings of lectures most times are monolithic entities that cannot be integrated into an active learning process offhand. We present the web-based E-Librarian service CHESt that matches a user's question given in natural language to a selection of semantically pertinent lecture recordings based on an adapted best cover algorithm. Our e-Librarian Service is able to augment the educational value of lecture recordings and thus, to overcome the current deadlock situation in e-learning.
44. RiMOM: Ontology Alignment with Strategy Selection , Yi Li,Juanzi Li and Jie Tang
    We demonstrate our ontology alignment tool, RiMOM. RiMOM integrates multiple strategies for ontology alignment. It utilizes a strategy selection module to dynamically determine which strategies should be used in the alignment for different tasks. RiMOM provides a friendly user interface for alignment tracking and customization. In addition, RiMOM currently supports alignment from a database schema to an ontology. RiMOM participated in OAEI2006 and obtained the best results on the benchmark datasets.
45. SPARQL Query Optimization Using Selectivity Estimation , Abraham Bernstein,Markus Stocker and Christoph Kiefer
    This poster describes three static SPARQL optimization approaches for in-memory RDF graphs: (1) a selectivity estimation index (SEI) for single query triple patterns; (2) a query pattern index (QPI) for joined triple patterns; and (3) a hybrid optimization approach that combines both indexes. Using the Lehigh University Benchmark (LUBM), we show that the hybrid approach outperforms other SPARQL query engines such as ARQ and Sesame for in-memory graphs.
46. SemBiz BPMO: Business Process Modeling Ontology , Zhixian Yan,Emilia Cimpian,Michal Zaremba and Ying Ding
    Semantically described business process is one of the most challenging research issues currently addressed by the semantic community. This paper proposes a Business Process Modeling Ontology in SemBiz, which contributes to bridging gap between the business designing perspective and the technical implementation level in BPM or workflow by semantic descriptions of business processes.
47. Semantic Personal Media Management System using Uniform Representation based on Ontology , Young-Tack Park,Jung-Hwa Choi and Sung-Chan Kim
    Everyday individual wants to record, annotate, and manipulate digital media in their own ways. Semantic web supports users to represent annotations in forms that bear personal semantic meaning. An essential feature of personal media management systems is to give individual users significant control over representation, annotation and query their media information. In our framework, na�ve users create their personalized ontology for describing their media information and construct semantically rich metadata collections using the personalized media ontology. Our system allows users to provide expressive queries in their own ontology. Queries are represented by OWL classes or instances. The system uses a uniform representation of personalized ontology, metadata, and queries. Such a uniform representation enables the system to exploit description logic reasoner.
48. Semantic Web Architecture , Ila Nivas
    In this poster the semantic web architecture for 'open market' concept is described. 'Open market' is a commercial application of semantic technologies. The semantic web architecture elements have been categorized as: web service provider, web service requester and infrastructure elements. This architecture addresses the standard ontology discovery, semantic web service discovery, availability of semantic web content with embedded normative metadata and semantic web service integration automation requirements of the semantic web.
49. Situated Ontology Mapping with Wikipedia , Bo Hu
    We propose an approach that collaborates the logic formalisms with collaboratively created web repositories. A logic conceptualisation based "signaturing" algorithm is to discover, from concept definitions, the feature vectors that uniquely identify concepts while web repositories are used to understand the implications of these features.
50. SocioBiblog: A Decentralized Platform for Sharing Bibliographic Information , Aman Shakya,Hideaki Takeda,Vilas Wuwongse and Ikki Ohmukai
    Sharing of bibliographic information is very important in research communities. SocioBiblog is a semantic blogging system that provides a decentralized environment for this. The SWRC ontology has been used for adding metadata about publications in blogs. SocioBiblog aggregates publications from the social network neighborhood and co-authors of a researcher. RSS aggregation has been extended to handle embedded publication metadata in BuRST feeds. Interoperability with other systems has been maintained by adopting standard formats. The aggregated collections may be searched and filtered flexibly by metadata criteria. The results can be redistributed as new feeds. Thus, a decentralized ecosystem can be formed where each unit can publish, aggregate and redistribute information.
51. Test Collection Construction for QA system using Ontology Instance Triplet , Yoonyoung Nam and Key-Sun Choi
    This paper presents the constructing of a QA test collection using ontology instance knowledge. We construct test collection to verify the question-answering system based on ontologies. We define the ontology triplet from IT device ontology and people ontology. We use semantic restriction of relation name to classify query types and E-K translation to generate the Korean test collection. Relation names are expanded using the WordNet synset.
52. The Culture Finder: Personalized Search Service in Semantic Web , Je-Min Kim and Young-Tack Park
    Semantic search would result in an overwhelming number of results for users are increased, therefore elevating the need for appropriate personalized schemes. In this paper, we also present the structure used in the Culture Finder to support personalized search service. The Culture Finder helps semantic web agents obtain personalized culture information.
53. The Sediment Metaphor: Serendipity for Browsing Ontologies , Katharina Siorpaes,Martin Hepp and Andreas Klotz
    Navigating ontologies can be a cumbersome task: existing approaches to ontology visualization have several shortcomings including that elements are neither sorted by relevance nor do they adapt to changing user requirements. We present a novel technique for user interfaces of semantic systems based on an adaptive extension of the tag cloud paradigm.
54. Understanding an Ontology in RDFS by Ranking its Concepts and Relations , Gang Wu,Juanzi Li,Tao Li and Kehong Wang
    Ranking the importance of concepts and relations in an ontology and highlight those having high rank scores is an intuitive and effective approach to support the understanding of an ontology for further developments and reuses. In this paper, we propose CARRank, to efficiently and simultaneously rank the importance of concepts and relations. Its uniqueness lies in that it mutually reinforces between the importance of concepts and the weights of relations, and it performs in a reverse PageRank manner.
55. Watson: A Gateway for Next Generation Semantic Web Applications , Mathieu d'Aquin,Claudio Baldassarre,Laurian Gridinoc,Sofia Angeletou,Marta Sabou and Enrico Motta
    The amount of knowledge published on the Semantic Web - i.e, the number of ontologies and semantic documents available online - is rapidly increasing. Following this evolution, changes appear in the way semantic applications are designed: instead of relying on one, self engineered base of semantic data, these next generation Semantic Web applications assume the existence and availability of a large scale, distributed Web of data. In order for these applications to be able to exploit and combine the increasing amount of semantic data and ontologies available online, a gateway to the Semantic Web is required.
56. WebKER: A Wrapper Learning-based Tool for Extracting Knowledge , Xi Bai and Jigui Sun
    This paper proposes WebKER, a system for extracting knowledge from Web documents based on domain ontologies and suffix-array-based wrapper learning. It also gives the performance evaluation of this system and the comparison between querying information in the Knowledge Base (KB) and querying information in the traditional database. Moreover, the outstanding-wrapper selection and a novel method for linking and merging the knowledge are also presented.
57. WikiFactory: An ontology-driven software framework for semantic web sites , Paolo Ciancarini,Aldo Gangemi,Giorgia Lodi,Jacopo Penazzi and Valentina Presutti
    We present WikiFactory, a tool that enables an automatic, ontology-driven deployment of a semantic wiki, where the ontology describes a specific domain of interest. The resulting deployed semantic wiki can be used as a friendly interface to domain experts, for ontology browsing and editing of both ontology and content. WikiFactory also provides run time synchronization between ontology and content: changes made over wiki content are reflected upon the underlying ontology, and viceversa.
58. Working Towards Ontology Generation from Context of Listening to Presentations , Yuki Matsuoka,Ikki Ohmukai and Hideaki Takeda
    Many studies have been conducted concerning ontology generation from the tags of social tagging services and some tagging services target academic literature. We think that it is unsuitable to search for technical information using the generated ontology from these tags, because they are often taken directly from the contents. In order to obtain contextual information on the papers, we focused on the notes taken when users listen to a presentation. We implemented and applied a system where the participants can input two kinds of memos on Web pages for presentations at conferences. As a result of this operation, we obtained words related to the content of the papers and to the background knowledge and research details.
59. myOntology: Tapping the Wisdom of Crowds for Ontology Building , Katharina Siorpaes,Martin Hepp,Andreas Klotz and Michael Waltl
    Despite very active research on ontologies, only a small amount of useful ontologies can be found on the Web. The reasons for this are manifold, but a major obstacle is that ontology engineering environments impose high entrance barriers on users, and that the community does not have direct control over the ontology evolution. In the myOntology project, we propose the use of a Wiki supported by sophisticated background functionality to enable community-driven ontology building by giving users with no or little expertise in ontology engineering the opportunity to contribute.