In diesem Beitragwird einKonzept vorgestellt, das für die Planung und Erweiterung eines 1:1-Noteb... more In diesem Beitragwird einKonzept vorgestellt, das für die Planung und Erweiterung eines 1:1-Notebook-Projekts an einer Schule ausgearbeitet wurde. Anstatt die Planung des Gesamtprojektes unde inzelner Unterrichtseinheiten monolithischzubetrachten,sieht dieses Konzept eine Ansicht in drei Dimensionen vor: eine pädagogische,e inem aterielleu nd eine soziale Dimension. Im Allgemeineni st es das Ziel, "Goldene Regeln"f ür denN otebook-Einsatz im Klassenraum anzugeben, unterstützt durchg ezielte Weiterbildungen und informellenAustausch zwischen denLehrerinnen undLehrern. 1B eschreibung der Schule und des ursprünglichen Konzepts 1.1S chule undFinanzierungsmodell Das "Lycée Aline Mayrisch Luxembourg" (LAML) ist eine Schule in Luxemburgm it rund 1500 Schülernu nd 180 Lehrerinnenu nd Lehrern. Alle Jahrgänge vond er siebten bisz ur dreizehnten Klasse werdena ngeboten.M it demd eutschen Schulsystem verglichen, handelt es sich bei demL AMLu me ine Kombinationa us Gymnasium, Realschule undH auptschule: In denJ ahrgängen7bis9gibt es alle Klassend ieser unterschiedlichenSchulformen,abKlasse 10 gibt es nurnochGymnasialklassen. Alsd as LAML 2001 die ersten Schülerinnenu nd Schüler empfing, ware s die erste Schule in Luxemburg, die das pädagogische Konzept des mobilen Lernensumsetzte.Die Idee ware infach: jederS chüler bekommt einN otebook,d as er innerhalb derS chule überall einsetzen kann (1:1-Notebook-Projekt). Jährlich werdenv on derS chule rund 280 neue Laptops gekauft. Diese ntspricht der Anzahl an neuenS chülern, die sich jedes Jahr freiwillig, prinzipiell fürd ie siebten Klassen dieser Schule, bewerben. Die Schule bezieht die Notebooksn ache iner
Designing the Multimedia Information Retrieval Module
X.media.publishing, 2011
The core component of an E-Librarian Service is the multimedia information retrieval (MIR) module... more The core component of an E-Librarian Service is the multimedia information retrieval (MIR) module that performs a semantic search over the knowledge base. Its task is to retrieve only semantically pertinent documents with respect to a given user query. Among all the documents in the knowledge base that have some common information with the user query, the MIR module is able to identify the most pertinent match(es), keeping in mind that the user in general expects an exhaustive answer while preferring a concise answer with only little or no information overload.
The Semantic Web is an evolving extension of the World Wide Web in which Web content can be expre... more The Semantic Web is an evolving extension of the World Wide Web in which Web content can be expressed not only in natural language, but also in a form that can be read and “understood” by software agents, thus permitting them to find, share, and integrate information more easily. It derives from Tim Berners-Lee’s vision of the Web as a universal medium for data, information, and knowledge exchange.
Obwohl sich die Verfügbarkeit von pädagogischen Inhalten in elektronischer Form stetig erhöht, is... more Obwohl sich die Verfügbarkeit von pädagogischen Inhalten in elektronischer Form stetig erhöht, ist deren Nutzen in einem schulischen Umfeld recht gering. Die Hauptursache dessen ist, dass es zu viele unzuverlässige, redundante und nicht relevante Informationen gibt. Das Finden von passenden Lernobjekten ist eine schwierige Aufgabe, die vom benutzerbasierten Filtern der passenden Informationen abhängig ist. Damit Wissensbanken wie das online Tele-TASK Archiv zu nützlichen, pädagogischen Ressourcen werden, müssen Lernobjekte korrekt, zuverlässig und in maschinenverständlicher Form identifiziert werden, sowie effiziente Suchwerkzeuge entwickelt werden. Unser Ziel ist es, einen E-Bibliothekar-Dienst zu schaffen, der multimediale Ressourcen in einer Wissensbank auf effizientere Art und Weise findet als mittels Navigieren durch ein Inhaltsverzeichnis oder mithilfe einer einfachen Stichwortsuche. Unsere Prämisse ist, dass passendere Ergebnisse gefunden werden könnten, wenn die semantische Suchmaschine den Sinn der Benutzeranfrage verstehen würde. In diesem Fall wären die gelieferten Antworten logische Konsequenzen einer Inferenz und nicht die einer Schlüsselwortsuche. Tests haben gezeigt, dass unser E-Bibliothekar-Dienst unter allen Dokumenten in einer gegebenen Wissensbank diejenigen findet, die semantisch am besten zur Anfrage des Benutzers passen. Dabei gilt, dass der Benutzer eine vollständige und präzise Antwort erwartet, die keine oder nur wenige Zusatzinformationen enthält. Außerdem ist unser System in der Lage, dem Benutzer die Qualität und Pertinenz der gelieferten Antworten zu quantifizieren und zu veranschaulichen. Schlussendlich liefert unser E-Bibliothekar-Dienst dem Benutzer immer eine Antwort, selbst wenn das System feststellt, dass es keine vollständige Antwort auf die Frage gibt. Unser E-Bibliothekar-Dienst ermöglicht es dem Benutzer, seine Fragen in einer sehr einfachen und menschlichen Art und Weise auszudrücken, nämlich in natürlicher Sprache. Linguistische Informationen und ein gegebener Kontext in Form einer Ontologie werden für die semantischë Ubersetzung der Benutzereingabe in eine logische Form benutzt. Unser E-Bibliothekar-Dienst wurde prototypisch in drei unterschiedliche pädagogische Werkzeuge umgesetzt. In zwei Experimenten wurde in einem pädagogischen Umfeld die Angemessenheit und die Zuverlässigkeit dieser Werkzeuge als Komplement zum klassischen Unterricht geprüft. Die Hauptergebnisse sind folgende: Erstens wurde festgestellt, dass Schüler generell akzeptieren, ganze Fragen einzugeben-anstelle von Stichwörtern-wenn dies ihnen hilft, bessere Suchresultate zu erhalten. Zweitens, das wichtigste Resultat aus den Experimenten ist die Erkenntnis, dass Schuleresultate verbessert werden können, wenn Schüler unseren E-Bibliothekar-Dienst verwenden. Wir haben eine generelle Verbesserung von 5% der Schulresultate gemessen. 50% der Schüler haben ihre Schulnoten verbessert, 41% von ihnen sogar maßgeblich. Einer der Hauptgründe für diese positiven Resultate ist, dass die Schüler motivierter waren und folglich bereit waren, mehr Einsatz und Fleiß in das Lernen und in das Erwerben von neuem Wissen zu investieren. iii Overview Although educational content in electronic form is increasing dramatically, its usage in an educational environment is poor, mainly due to the fact that there is too much of (unreliable) redundant, and not relevant information. Finding appropriate answers is a rather difficult task being reliant on the user filtering of the pertinent information from the noise. Turning knowledge bases like the online tele-TASK archive into useful educational resources requires identifying correct, reliable, and "machine-understandable" information, as well as developing simple but efficient search tools with the ability to reason over this information. Our vision is to create an E-Librarian Service, which is able to retrieve multimedia resources from a knowledge base in a more efficient way than by browsing through an index, or by using a simple keyword search. In our E-Librarian Service, the user can enter his question in a very simple and human way; in natural language (NL). Our premise is that more pertinent results would be retrieved if the search engine understood the sense of the user's query. The returned results are then logical consequences of an inference rather than of keyword matchings. Our E-Librarian Service does not return the answer to the user's question, but it retrieves the most pertinent document(s), in which the user finds the answer to his/her question. Among all the documents that have some common information with the user query, our E-Librarian Service identifies the most pertinent match(es), keeping in mind that the user expects an exhaustive answer while preferring a concise answer with only little or no information overhead. Also, our E-Librarian Service always proposes a solution to the user, even if the system concludes that there is no exhaustive answer. Our E-Librarian Service was implemented prototypically in three different educational tools. A first prototype is CHESt (Computer History Expert System); it has a knowledge base with 300 multimedia clips that cover the main events in computer history. A second prototype is MatES (Mathematics Expert System); it has a knowledge base with 115 clips that cover the topic of fractions in mathematics for secondary school w.r.t. the official school programme. All clips were recorded mainly by pupils. The third and most advanced prototype is the "Lecture Butler's E-Librarain Service"; it has a Web service interface to respect a service oriented architecture (SOA), and was developed in the context of the Web-University project at the Hasso-Plattner-Institute (HPI). Two major experiments in an educational environment-at the Lycée Technique Esch/Alzette in Luxembourg-were made to test the pertinence and reliability of our E-Librarian Service as a complement to traditional courses. The first experiment (in 2005) was made with CHESt in different classes, and covered a single lesson. The second experiment (in 2006) covered a period of 6 weeks of intensive use of MatES in one class. There was no classical mathematics lesson where the teacher gave explanations, but the students had to learn in an autonomous and exploratory way. They had to ask questions to the E-Librarian Service just the way they would if there was a human teacher. iv This thesis could not have been written without the support of lots of people. First of all, I would like to thank my doctor-father Prof. Dr. Christoph Meinel-who gave me the opportunity to start as an external Ph.D. student and always had an open door for me-for all the interesting discussions and comments. A lot of ideas that I elaborated on this thesis originated from our discussions. Prof. Meinel taught me a lot of things beyond computer science and turned the years of my Ph.D. work into an amazing adventure. I feel a deep sense of gratitude towards my wife Magali for providing technical help and advice, and for continuously encouraging me in moments of stress and resignation. I also want to express my gratitude to Prof. Dr. Djamshid Tavangarian, Prof. Dr. Thomas Engel and Prof. Dr. Abraham Bernstein who have accepted to review this thesis, to Isabelle Wirth for correcting my English errors in this document, and to Carole Dording who spent uncountable hours on elaborating the knowledge base of MatES and on supervising the experiment in school. This research project was supported by Luxembourg International Advanced Studies in Information Technologies (LIASIT). Therefore, my special thanks goes to Prof. Dr. Thomas Engel and the whole LIASIT "family" for their support. I want to express my gratitude to the former and to today's board of directors of the Lycée Technique Esch/Alzette (LTE) for supporting this research project and for being part of it as "external partner". In particular, I am grateful for being granted the authorization to test some of the prototypes in a real school environment. I would also like to thank Dr. Naouel Karam, Dr. Laurent Debrauwer and Dr. Harald Sack for all the interesting meetings, explanations, reviews and comments, and Monique Reichert for the preparation and evaluation of the CHESt experiment. Besides all the personal acknowledgements, I would like to thank all the (former) staff of the chair "Internet Technologies-and Systems" at the Hasso-Plattner-Institute for their help, encouragement, and the numerous rewarding moments we spent together. All the people with whom I had the chance to interact in the course of this project have greatly enriched my life. Finally, I want to express my gratitude towards my parents who have always believed in me and encourage me accordingly. v vi This chapter is organized as follows. Section 1.1 will give a short introduction to (digital) libraries and librarians, and their role in education. We will formulate in section 1.2 our vision to create an E-Librarian Service, and emphasize its major characteristics. Section 1.3 will summarize the contributions while section 1.4 will give an overview of the structure of the thesis. 1.1.2 Libraries and Education The unique task of libraries and information services is that they respond to the particular questions and needs of individuals. This complements the general transmission of knowledge by the media, and makes libraries and information services vital to a democratic and open Information Society. Libraries are essential for a well informed citizenry and transparent governance. Libraries in education institutions have developed a wide range of services to meet the educational objectives of their parent institutions. School libraries clearly need to support the curriculum, but they also collect books and other materials to encourage reading and spirit of enquiry, as well as to meet the needs of the teachers and administrative staff. This versatile project focuses on the design,...
In this paper we present an e-librarian service which is able to retrieve multimedia resources fr... more In this paper we present an e-librarian service which is able to retrieve multimedia resources from a knowledge base in a more efficient way than by browsing through an index or by using a simple keyword search. Our premise is that more pertinent results would be retrieved if the e-librarian service had a semantic search engine which understood the sense of the user's query. This requires that the user must be given the means to enter semantics. We explored the approach to allow the user to formulate a complete question in natural language. The background theory was implemented in two different prototypes.
In this paper we describe the role of teachers in the cyber-age and how new teaching methods i n ... more In this paper we describe the role of teachers in the cyber-age and how new teaching methods i n a computer-based l earning environment can foster exploratory learning. An overview of modern e-learning technologies is described and illustrated with examples. We also present our e-learning tool CHESt; an interactive expert system that answers students' questions expressed in natural language. Then we present the results of experiments made in schools with CHESt. We discuss the pertinence and convenience of keyword and semantic search engines as didactical tool for querying multimedia knowledge sources. Finally, we analyze how students accept to enter complete questions in a semantic search to reduce the number of results, in opposition to a keyword search.
In diesem Papier stellenwir dieErgebnisseeines Experiments mitunsereme-Bibliothekarsystem" MatES"... more In diesem Papier stellenwir dieErgebnisseeines Experiments mitunsereme-Bibliothekarsystem" MatES" vor, einem e-Learning Werkzeug zumE rlernendes Bruchrechnens in der Mathematik.MatES ermöglicht denSchülern, durch dasEingebenvollständiger Fragesätzesemantisch korrekteund relevantemultime-dialeAntworten zu bekommen. Eine Schulklasse von 22 Schülernnahma ndiesemf ünf Wochen dauerndenExperiment teil.D ie Schüler arbeiteten autonom,s telltenF ragena nM atES und lernten durch praktischeÜ bungen. DieM ultimedia-Erklärungen, dieM atES lieferte,e rmöglichten es denSchülernihr Wissen zu erweiternund ihre Übungenzulösen. DieS chüler erlebten MatESa ls hilfreiches,u nterstützendesW erkzeugb eimM athematiklernen.W ährend sieM atES benutzten,k onnten wirr elevante Verbesserungeni hrer schulischen Leistungenm essen, indemw ir dieR esultate miti hren früheren Ergebnissen verglichen.E ined er Hauptursachen dieser hervorragenden Resultatei st möglicherweised ie höhere Motivationd er Schüler,d as ie sich beim Lernen mehr Mühe gaben, um sich neues Wissen anzueignen.D ie Schüler haben auch festgestellt, dassM atES bessere rklärt und dass sied ie Inhalte viel leichter verstehen.
In this paper, we describe a method to retrieve documents based on the semantics of a user's ques... more In this paper, we describe a method to retrieve documents based on the semantics of a user's question, rather than on keywords. It is based on domain ontology and on RDF (Resource Description Framework) described knowledge. The user enters his question in natural language, which is then converted into an interpreted sentence of semantically relevant words. Each word is classified in a hierarchy of concepts in order to compute the exact semantics and the degree of importance for each of the used words. The interpreted user question is then mapped to a general assertion. Finally, a semantic query is generated, according to the mapped general assertion and the object values derived from the user question. Hence, only semantically relevant documents (resources) are found. This semantic retrieval method was implemented in an e-learning tool called CHESt (Computer History Expert System). We also present in this paper the results drawn from experiments with this tool, which was used as a complement in common school courses.
This paper describes our e-librarian service that understands students' complete questions in nat... more This paper describes our e-librarian service that understands students' complete questions in natural language and retrieves very few but pertinent learning objects, i.e., short multimedia documents. The system is based on three key components: the formal representation of a domain ontology, a mechanism to automatically identify learning objects out of a knowledge source, and a semantic search engine that yields only pertinent results based on the freely formulated questions in natural language. We report on experiments about students' acceptance to enter complete questions instead of only keywords, and about the benefits of such a virtual personal teacher in an educational environment.
In this article we present an e-librarian service which is able to retrieve multimedia resources ... more In this article we present an e-librarian service which is able to retrieve multimedia resources from a knowledge base in a more efficient way than by browsing through an index or by using a simple keyword search. Our premise is that more pertinent results would be retrieved if the e-librarian service had a semantic search engine which understood the sense of the user's query. We explored the approach to allow the user to formulate a complete question in natural language. We present our background theory, which is composed of three steps. Firstly, there is the linguistic pre-processing of the user question. Secondly, there is the semantic interpretation of the user question into a logical and unambiguous form, i. e., ALC terminology. Thirdly, there is the generation of a semantic query, and the retrieval of pertinent documents. The background theory was implemented in two prototypes. We report on experiments that confirm the feasibility, the quality and the benefits of such an e-librarian service. From 229 different user questions, the system returned for 97% of the questions the right answer, and for nearly half of the questions only one answer (the best one). Zusammenfassung In diesem Artikel stellen wir unseren E-Bibliothekar Dienst vor, der in der Lage ist, multimediale Ressourcen aus einer Wissensdatenbank in einer effizienteren Weise zu finden als es durch das Suchen in einem Index oder durch Benutzen einer Stichwortsuche möglich ist. Wir sind überzeugt, dass konkretere Resultate gefunden werden, wenn der E-Bibliothekar Dienst über eine semantische Suchmaschine verfügt, die den Sinn der Benutzeranfrage versteht. Wir erforschen die Möglichkeit der Benutzereingabe einer ganzen Frage in natürlicher Sprache. Unsere Lösung besteht aus drei Schritten. Erstens gibt es die linguistische Aufbereitung der Benutzerfrage. Zweitens gibt es die semantische Interpretation der Benutzerfrage in eine logische und eindeutige Form, in unserem Fall in eine ALC Terminologie. Drittens gibt es die Erzeugung einer semantischen Frage und das Finden der passenden Dokumente. Unsere Lösung wurde in zwei Prototypen implementiert. Wir berichten über Experimente, die die Durchführbarkeit, die Qualität und den Nutzen eines solchen E-Bibliothekar Dienstes bestätigen. Von 229 unterschiedlichen Benutzerfragen fand unser System in 97% der Fälle die passende Antwort und für die Hälfte der Fragen nur eine einzige-und zwar die beste-Antwort.
To make this section self-containing, we are going to start with a short summary of some properti... more To make this section self-containing, we are going to start with a short summary of some properties within probability theory. An event A is an assertion (or proposition) about the result of an experiment, and P(A) is the probability that an event happens with 0 = P(A) = 1. E.g., A = “throwing a 6 with a dice”, then P(A) = \(\frac{1}{6}.\)
Towards to an automatic semantic annotation for multimedia learning objects
ABSTRACT The number of digital video recordings has increased dra-matically. The idea of recordin... more ABSTRACT The number of digital video recordings has increased dra-matically. The idea of recording lectures, speeches, and other academic events is not new. But, the accessibility and traceability of its content for further use is rather lim-ited. Searching multimedia data, in ...
ABSTRACT An E-Librarian Service allows users to enter complete questions in natural language (NL)... more ABSTRACT An E-Librarian Service allows users to enter complete questions in natural language (NL) in order to improve the retrieval capabilities (see section 1.3.3). The aim of the natural language processing (NLP) module of an E-Librarian Service is to translate a user question into a logical and computer-readable form. The more precise and accurate this translation is, the more complex the algorithm gets. In this chapter we present the necessary principles to design the NLP module of an E-Librarian Service that is able to “understand” the meaning of a user question and to translate it into a logical form.
In diesem Beitragwird einKonzept vorgestellt, das für die Planung und Erweiterung eines 1:1-Noteb... more In diesem Beitragwird einKonzept vorgestellt, das für die Planung und Erweiterung eines 1:1-Notebook-Projekts an einer Schule ausgearbeitet wurde. Anstatt die Planung des Gesamtprojektes unde inzelner Unterrichtseinheiten monolithischzubetrachten,sieht dieses Konzept eine Ansicht in drei Dimensionen vor: eine pädagogische,e inem aterielleu nd eine soziale Dimension. Im Allgemeineni st es das Ziel, "Goldene Regeln"f ür denN otebook-Einsatz im Klassenraum anzugeben, unterstützt durchg ezielte Weiterbildungen und informellenAustausch zwischen denLehrerinnen undLehrern. 1B eschreibung der Schule und des ursprünglichen Konzepts 1.1S chule undFinanzierungsmodell Das "Lycée Aline Mayrisch Luxembourg" (LAML) ist eine Schule in Luxemburgm it rund 1500 Schülernu nd 180 Lehrerinnenu nd Lehrern. Alle Jahrgänge vond er siebten bisz ur dreizehnten Klasse werdena ngeboten.M it demd eutschen Schulsystem verglichen, handelt es sich bei demL AMLu me ine Kombinationa us Gymnasium, Realschule undH auptschule: In denJ ahrgängen7bis9gibt es alle Klassend ieser unterschiedlichenSchulformen,abKlasse 10 gibt es nurnochGymnasialklassen. Alsd as LAML 2001 die ersten Schülerinnenu nd Schüler empfing, ware s die erste Schule in Luxemburg, die das pädagogische Konzept des mobilen Lernensumsetzte.Die Idee ware infach: jederS chüler bekommt einN otebook,d as er innerhalb derS chule überall einsetzen kann (1:1-Notebook-Projekt). Jährlich werdenv on derS chule rund 280 neue Laptops gekauft. Diese ntspricht der Anzahl an neuenS chülern, die sich jedes Jahr freiwillig, prinzipiell fürd ie siebten Klassen dieser Schule, bewerben. Die Schule bezieht die Notebooksn ache iner
Designing the Multimedia Information Retrieval Module
X.media.publishing, 2011
The core component of an E-Librarian Service is the multimedia information retrieval (MIR) module... more The core component of an E-Librarian Service is the multimedia information retrieval (MIR) module that performs a semantic search over the knowledge base. Its task is to retrieve only semantically pertinent documents with respect to a given user query. Among all the documents in the knowledge base that have some common information with the user query, the MIR module is able to identify the most pertinent match(es), keeping in mind that the user in general expects an exhaustive answer while preferring a concise answer with only little or no information overload.
The Semantic Web is an evolving extension of the World Wide Web in which Web content can be expre... more The Semantic Web is an evolving extension of the World Wide Web in which Web content can be expressed not only in natural language, but also in a form that can be read and “understood” by software agents, thus permitting them to find, share, and integrate information more easily. It derives from Tim Berners-Lee’s vision of the Web as a universal medium for data, information, and knowledge exchange.
Obwohl sich die Verfügbarkeit von pädagogischen Inhalten in elektronischer Form stetig erhöht, is... more Obwohl sich die Verfügbarkeit von pädagogischen Inhalten in elektronischer Form stetig erhöht, ist deren Nutzen in einem schulischen Umfeld recht gering. Die Hauptursache dessen ist, dass es zu viele unzuverlässige, redundante und nicht relevante Informationen gibt. Das Finden von passenden Lernobjekten ist eine schwierige Aufgabe, die vom benutzerbasierten Filtern der passenden Informationen abhängig ist. Damit Wissensbanken wie das online Tele-TASK Archiv zu nützlichen, pädagogischen Ressourcen werden, müssen Lernobjekte korrekt, zuverlässig und in maschinenverständlicher Form identifiziert werden, sowie effiziente Suchwerkzeuge entwickelt werden. Unser Ziel ist es, einen E-Bibliothekar-Dienst zu schaffen, der multimediale Ressourcen in einer Wissensbank auf effizientere Art und Weise findet als mittels Navigieren durch ein Inhaltsverzeichnis oder mithilfe einer einfachen Stichwortsuche. Unsere Prämisse ist, dass passendere Ergebnisse gefunden werden könnten, wenn die semantische Suchmaschine den Sinn der Benutzeranfrage verstehen würde. In diesem Fall wären die gelieferten Antworten logische Konsequenzen einer Inferenz und nicht die einer Schlüsselwortsuche. Tests haben gezeigt, dass unser E-Bibliothekar-Dienst unter allen Dokumenten in einer gegebenen Wissensbank diejenigen findet, die semantisch am besten zur Anfrage des Benutzers passen. Dabei gilt, dass der Benutzer eine vollständige und präzise Antwort erwartet, die keine oder nur wenige Zusatzinformationen enthält. Außerdem ist unser System in der Lage, dem Benutzer die Qualität und Pertinenz der gelieferten Antworten zu quantifizieren und zu veranschaulichen. Schlussendlich liefert unser E-Bibliothekar-Dienst dem Benutzer immer eine Antwort, selbst wenn das System feststellt, dass es keine vollständige Antwort auf die Frage gibt. Unser E-Bibliothekar-Dienst ermöglicht es dem Benutzer, seine Fragen in einer sehr einfachen und menschlichen Art und Weise auszudrücken, nämlich in natürlicher Sprache. Linguistische Informationen und ein gegebener Kontext in Form einer Ontologie werden für die semantischë Ubersetzung der Benutzereingabe in eine logische Form benutzt. Unser E-Bibliothekar-Dienst wurde prototypisch in drei unterschiedliche pädagogische Werkzeuge umgesetzt. In zwei Experimenten wurde in einem pädagogischen Umfeld die Angemessenheit und die Zuverlässigkeit dieser Werkzeuge als Komplement zum klassischen Unterricht geprüft. Die Hauptergebnisse sind folgende: Erstens wurde festgestellt, dass Schüler generell akzeptieren, ganze Fragen einzugeben-anstelle von Stichwörtern-wenn dies ihnen hilft, bessere Suchresultate zu erhalten. Zweitens, das wichtigste Resultat aus den Experimenten ist die Erkenntnis, dass Schuleresultate verbessert werden können, wenn Schüler unseren E-Bibliothekar-Dienst verwenden. Wir haben eine generelle Verbesserung von 5% der Schulresultate gemessen. 50% der Schüler haben ihre Schulnoten verbessert, 41% von ihnen sogar maßgeblich. Einer der Hauptgründe für diese positiven Resultate ist, dass die Schüler motivierter waren und folglich bereit waren, mehr Einsatz und Fleiß in das Lernen und in das Erwerben von neuem Wissen zu investieren. iii Overview Although educational content in electronic form is increasing dramatically, its usage in an educational environment is poor, mainly due to the fact that there is too much of (unreliable) redundant, and not relevant information. Finding appropriate answers is a rather difficult task being reliant on the user filtering of the pertinent information from the noise. Turning knowledge bases like the online tele-TASK archive into useful educational resources requires identifying correct, reliable, and "machine-understandable" information, as well as developing simple but efficient search tools with the ability to reason over this information. Our vision is to create an E-Librarian Service, which is able to retrieve multimedia resources from a knowledge base in a more efficient way than by browsing through an index, or by using a simple keyword search. In our E-Librarian Service, the user can enter his question in a very simple and human way; in natural language (NL). Our premise is that more pertinent results would be retrieved if the search engine understood the sense of the user's query. The returned results are then logical consequences of an inference rather than of keyword matchings. Our E-Librarian Service does not return the answer to the user's question, but it retrieves the most pertinent document(s), in which the user finds the answer to his/her question. Among all the documents that have some common information with the user query, our E-Librarian Service identifies the most pertinent match(es), keeping in mind that the user expects an exhaustive answer while preferring a concise answer with only little or no information overhead. Also, our E-Librarian Service always proposes a solution to the user, even if the system concludes that there is no exhaustive answer. Our E-Librarian Service was implemented prototypically in three different educational tools. A first prototype is CHESt (Computer History Expert System); it has a knowledge base with 300 multimedia clips that cover the main events in computer history. A second prototype is MatES (Mathematics Expert System); it has a knowledge base with 115 clips that cover the topic of fractions in mathematics for secondary school w.r.t. the official school programme. All clips were recorded mainly by pupils. The third and most advanced prototype is the "Lecture Butler's E-Librarain Service"; it has a Web service interface to respect a service oriented architecture (SOA), and was developed in the context of the Web-University project at the Hasso-Plattner-Institute (HPI). Two major experiments in an educational environment-at the Lycée Technique Esch/Alzette in Luxembourg-were made to test the pertinence and reliability of our E-Librarian Service as a complement to traditional courses. The first experiment (in 2005) was made with CHESt in different classes, and covered a single lesson. The second experiment (in 2006) covered a period of 6 weeks of intensive use of MatES in one class. There was no classical mathematics lesson where the teacher gave explanations, but the students had to learn in an autonomous and exploratory way. They had to ask questions to the E-Librarian Service just the way they would if there was a human teacher. iv This thesis could not have been written without the support of lots of people. First of all, I would like to thank my doctor-father Prof. Dr. Christoph Meinel-who gave me the opportunity to start as an external Ph.D. student and always had an open door for me-for all the interesting discussions and comments. A lot of ideas that I elaborated on this thesis originated from our discussions. Prof. Meinel taught me a lot of things beyond computer science and turned the years of my Ph.D. work into an amazing adventure. I feel a deep sense of gratitude towards my wife Magali for providing technical help and advice, and for continuously encouraging me in moments of stress and resignation. I also want to express my gratitude to Prof. Dr. Djamshid Tavangarian, Prof. Dr. Thomas Engel and Prof. Dr. Abraham Bernstein who have accepted to review this thesis, to Isabelle Wirth for correcting my English errors in this document, and to Carole Dording who spent uncountable hours on elaborating the knowledge base of MatES and on supervising the experiment in school. This research project was supported by Luxembourg International Advanced Studies in Information Technologies (LIASIT). Therefore, my special thanks goes to Prof. Dr. Thomas Engel and the whole LIASIT "family" for their support. I want to express my gratitude to the former and to today's board of directors of the Lycée Technique Esch/Alzette (LTE) for supporting this research project and for being part of it as "external partner". In particular, I am grateful for being granted the authorization to test some of the prototypes in a real school environment. I would also like to thank Dr. Naouel Karam, Dr. Laurent Debrauwer and Dr. Harald Sack for all the interesting meetings, explanations, reviews and comments, and Monique Reichert for the preparation and evaluation of the CHESt experiment. Besides all the personal acknowledgements, I would like to thank all the (former) staff of the chair "Internet Technologies-and Systems" at the Hasso-Plattner-Institute for their help, encouragement, and the numerous rewarding moments we spent together. All the people with whom I had the chance to interact in the course of this project have greatly enriched my life. Finally, I want to express my gratitude towards my parents who have always believed in me and encourage me accordingly. v vi This chapter is organized as follows. Section 1.1 will give a short introduction to (digital) libraries and librarians, and their role in education. We will formulate in section 1.2 our vision to create an E-Librarian Service, and emphasize its major characteristics. Section 1.3 will summarize the contributions while section 1.4 will give an overview of the structure of the thesis. 1.1.2 Libraries and Education The unique task of libraries and information services is that they respond to the particular questions and needs of individuals. This complements the general transmission of knowledge by the media, and makes libraries and information services vital to a democratic and open Information Society. Libraries are essential for a well informed citizenry and transparent governance. Libraries in education institutions have developed a wide range of services to meet the educational objectives of their parent institutions. School libraries clearly need to support the curriculum, but they also collect books and other materials to encourage reading and spirit of enquiry, as well as to meet the needs of the teachers and administrative staff. This versatile project focuses on the design,...
In this paper we present an e-librarian service which is able to retrieve multimedia resources fr... more In this paper we present an e-librarian service which is able to retrieve multimedia resources from a knowledge base in a more efficient way than by browsing through an index or by using a simple keyword search. Our premise is that more pertinent results would be retrieved if the e-librarian service had a semantic search engine which understood the sense of the user's query. This requires that the user must be given the means to enter semantics. We explored the approach to allow the user to formulate a complete question in natural language. The background theory was implemented in two different prototypes.
In this paper we describe the role of teachers in the cyber-age and how new teaching methods i n ... more In this paper we describe the role of teachers in the cyber-age and how new teaching methods i n a computer-based l earning environment can foster exploratory learning. An overview of modern e-learning technologies is described and illustrated with examples. We also present our e-learning tool CHESt; an interactive expert system that answers students' questions expressed in natural language. Then we present the results of experiments made in schools with CHESt. We discuss the pertinence and convenience of keyword and semantic search engines as didactical tool for querying multimedia knowledge sources. Finally, we analyze how students accept to enter complete questions in a semantic search to reduce the number of results, in opposition to a keyword search.
In diesem Papier stellenwir dieErgebnisseeines Experiments mitunsereme-Bibliothekarsystem" MatES"... more In diesem Papier stellenwir dieErgebnisseeines Experiments mitunsereme-Bibliothekarsystem" MatES" vor, einem e-Learning Werkzeug zumE rlernendes Bruchrechnens in der Mathematik.MatES ermöglicht denSchülern, durch dasEingebenvollständiger Fragesätzesemantisch korrekteund relevantemultime-dialeAntworten zu bekommen. Eine Schulklasse von 22 Schülernnahma ndiesemf ünf Wochen dauerndenExperiment teil.D ie Schüler arbeiteten autonom,s telltenF ragena nM atES und lernten durch praktischeÜ bungen. DieM ultimedia-Erklärungen, dieM atES lieferte,e rmöglichten es denSchülernihr Wissen zu erweiternund ihre Übungenzulösen. DieS chüler erlebten MatESa ls hilfreiches,u nterstützendesW erkzeugb eimM athematiklernen.W ährend sieM atES benutzten,k onnten wirr elevante Verbesserungeni hrer schulischen Leistungenm essen, indemw ir dieR esultate miti hren früheren Ergebnissen verglichen.E ined er Hauptursachen dieser hervorragenden Resultatei st möglicherweised ie höhere Motivationd er Schüler,d as ie sich beim Lernen mehr Mühe gaben, um sich neues Wissen anzueignen.D ie Schüler haben auch festgestellt, dassM atES bessere rklärt und dass sied ie Inhalte viel leichter verstehen.
In this paper, we describe a method to retrieve documents based on the semantics of a user's ques... more In this paper, we describe a method to retrieve documents based on the semantics of a user's question, rather than on keywords. It is based on domain ontology and on RDF (Resource Description Framework) described knowledge. The user enters his question in natural language, which is then converted into an interpreted sentence of semantically relevant words. Each word is classified in a hierarchy of concepts in order to compute the exact semantics and the degree of importance for each of the used words. The interpreted user question is then mapped to a general assertion. Finally, a semantic query is generated, according to the mapped general assertion and the object values derived from the user question. Hence, only semantically relevant documents (resources) are found. This semantic retrieval method was implemented in an e-learning tool called CHESt (Computer History Expert System). We also present in this paper the results drawn from experiments with this tool, which was used as a complement in common school courses.
This paper describes our e-librarian service that understands students' complete questions in nat... more This paper describes our e-librarian service that understands students' complete questions in natural language and retrieves very few but pertinent learning objects, i.e., short multimedia documents. The system is based on three key components: the formal representation of a domain ontology, a mechanism to automatically identify learning objects out of a knowledge source, and a semantic search engine that yields only pertinent results based on the freely formulated questions in natural language. We report on experiments about students' acceptance to enter complete questions instead of only keywords, and about the benefits of such a virtual personal teacher in an educational environment.
In this article we present an e-librarian service which is able to retrieve multimedia resources ... more In this article we present an e-librarian service which is able to retrieve multimedia resources from a knowledge base in a more efficient way than by browsing through an index or by using a simple keyword search. Our premise is that more pertinent results would be retrieved if the e-librarian service had a semantic search engine which understood the sense of the user's query. We explored the approach to allow the user to formulate a complete question in natural language. We present our background theory, which is composed of three steps. Firstly, there is the linguistic pre-processing of the user question. Secondly, there is the semantic interpretation of the user question into a logical and unambiguous form, i. e., ALC terminology. Thirdly, there is the generation of a semantic query, and the retrieval of pertinent documents. The background theory was implemented in two prototypes. We report on experiments that confirm the feasibility, the quality and the benefits of such an e-librarian service. From 229 different user questions, the system returned for 97% of the questions the right answer, and for nearly half of the questions only one answer (the best one). Zusammenfassung In diesem Artikel stellen wir unseren E-Bibliothekar Dienst vor, der in der Lage ist, multimediale Ressourcen aus einer Wissensdatenbank in einer effizienteren Weise zu finden als es durch das Suchen in einem Index oder durch Benutzen einer Stichwortsuche möglich ist. Wir sind überzeugt, dass konkretere Resultate gefunden werden, wenn der E-Bibliothekar Dienst über eine semantische Suchmaschine verfügt, die den Sinn der Benutzeranfrage versteht. Wir erforschen die Möglichkeit der Benutzereingabe einer ganzen Frage in natürlicher Sprache. Unsere Lösung besteht aus drei Schritten. Erstens gibt es die linguistische Aufbereitung der Benutzerfrage. Zweitens gibt es die semantische Interpretation der Benutzerfrage in eine logische und eindeutige Form, in unserem Fall in eine ALC Terminologie. Drittens gibt es die Erzeugung einer semantischen Frage und das Finden der passenden Dokumente. Unsere Lösung wurde in zwei Prototypen implementiert. Wir berichten über Experimente, die die Durchführbarkeit, die Qualität und den Nutzen eines solchen E-Bibliothekar Dienstes bestätigen. Von 229 unterschiedlichen Benutzerfragen fand unser System in 97% der Fälle die passende Antwort und für die Hälfte der Fragen nur eine einzige-und zwar die beste-Antwort.
To make this section self-containing, we are going to start with a short summary of some properti... more To make this section self-containing, we are going to start with a short summary of some properties within probability theory. An event A is an assertion (or proposition) about the result of an experiment, and P(A) is the probability that an event happens with 0 = P(A) = 1. E.g., A = “throwing a 6 with a dice”, then P(A) = \(\frac{1}{6}.\)
Towards to an automatic semantic annotation for multimedia learning objects
ABSTRACT The number of digital video recordings has increased dra-matically. The idea of recordin... more ABSTRACT The number of digital video recordings has increased dra-matically. The idea of recording lectures, speeches, and other academic events is not new. But, the accessibility and traceability of its content for further use is rather lim-ited. Searching multimedia data, in ...
ABSTRACT An E-Librarian Service allows users to enter complete questions in natural language (NL)... more ABSTRACT An E-Librarian Service allows users to enter complete questions in natural language (NL) in order to improve the retrieval capabilities (see section 1.3.3). The aim of the natural language processing (NLP) module of an E-Librarian Service is to translate a user question into a logical and computer-readable form. The more precise and accurate this translation is, the more complex the algorithm gets. In this chapter we present the necessary principles to design the NLP module of an E-Librarian Service that is able to “understand” the meaning of a user question and to translate it into a logical form.
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