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Auflistung nach Autor:in "Schulz, Stefan"

1 - 4 von 4
  • Konferenzbeitrag
    BioTopLite: An upper level ontology for the life sciences. Evolution, design and application
    (INFORMATIK 2013 – Informatik angepasst an Mensch, Organisation und Umwelt, 2013) Schulz, Stefan; Boeker, Martin
    OBJECTIVE: To present and theoretically underpin recent changes in the upper level ontology BioTopLite2 and to discuss the effectiveness of upper level ontologies in the design process of domain ontologies. BACKGROUNDs: BioTop is an upper level ontology for the life sciences, based on OWL DL. Experiences with the application of BioTop and changing requirements have required the introduction of a light version (BioTopLite). The usefulness of upper level ontologies is controversial. METHODS: This paper provides a survey over the evolution of BioTop, use cases, and lessons learnt. It presents the main features of a new version of BioTop, motivated by special domain requirements. In particular it is highlighted how the new version, BioTopLite2 addresses the problem of time-indexed relations between continuants, given the restriction to two-valued relations in OWL. RESULTS: The new version is optimized to more user-friendliness by reducing the relations to a minimum. BioTopLite is available at http://purl.org/biotop.
  • Konferenzbeitrag
    Kontext als Beziehung: Ein Kontextmodell für Mobiles Wissensmanagement
    (INFORMATIK 2003 – Innovative Informatikanwendungen, Band 2, Beiträge der 33. Jahrestagung der Gesellschaft für Informatik e.V. (GI), 2003) Schulz, Stefan
    Kontext und Kontextbewusstsein sind zwei der meist beanspruchten Begriffe in der Informations- und Kommunikationstechnologie. Insbesondere im Zeitalter mobiler Informationssysteme tritt die Aufgabe der Kontexterfassung immer mehr in den Vordergrund. Ein wichtiger Teil dieser Aufgabe ist das Management von Kontextinformationen und dessen Nutzung zur Entscheidungsautomatisierung bzw. -unterstützung. Um mit kontextuellen Informationen arbeiten zu können wird ein Modell benötigt, wie diese Informationen abgelegt werden können. Dieses Papier stellt ein solches Modell vor. Kontext wird hierbei als n-äre Beziehung zwischen Informationsobjekten verstanden und kann somit in die Strukturbeschreibung für anwendungsspezifisches Wissen eingebettet werden.
  • Konferenzbeitrag
    Measuring the effect of a guideline-based training on ontology design with a competency questions based evaluation approach
    (INFORMATIK 2013 – Informatik angepasst an Mensch, Organisation und Umwelt, 2013) Boeker, Martin; Grewe, Niels; Röhl, Johannes; Schober, Daniel; Schulz, Stefan; Seddig-Raufie, Djamila; Jansen, Ludger
    OBJECTIVE: (a) To measure the effect of a guideline-based training on the performance of ontology developers compared with the performance after unspecific training by a competency question based evaluation; and (b) to provide empirical evidence for the applicability of competency questions in formal ontology evaluation in general. BACKGROUND: A close connection between ontology development and ontology evaluation as quality management procedure can been attained with the use of competency questions. Competency questions are often used as a semi-formal specification of requirements for an ontology under development. Hence they can also be used as evaluation instruments, in order to check how far an ontology fulfills these requirements. METHODS: A randomized controlled trial was conducted with two groups of 12 students each. The intervention consisted in a differential guideline-based training on ontology development vs. unspecific training. After a group-specific training focusing on three topics per group, performance of students was assessed with 12 exercises (2 exercises per topic), in which the students had to apply their skills. Different types of competency questions were elaborated for the analysis of the students' ontologies. We used the proportion of correct answers as a measure of ontology quality. RESULTS: On single topic level, the performance of ontology developers increased after guideline-based training for two out of the six topics: it increased from a proportion of 0.46 to 0.63 for the topic Process \& Participation and from 0.44 to 0.53 for the topic Collective Material Entity. In regression analysis, a positive correlation was shown between the performance of students on untrained topics and the performance after specific guideline-based training. Moreover, in multiple regression analysis an overall effect of specific training of 0.09 was calculated (p < 0.1). CONCLUSION: The results show an effect of a specific guideline-based training on the performance of ontology developers compared to the performance after unspecific training by an increase of about 10 % on the rate of correct competency questions. In addition, this study has shown the general applicability of competency questions in a formal ontology evaluation scenario. However, the study also shows that the training of ontology developers and their performance evaluation is a tedious task. The resulting performance of ontology developers is more dependent on the a priori individual competencies than on the specific acquired skills after training.
  • Textdokument
    A study on the quality mindedness of students
    (Software Engineering im Unterricht der Hochschulen (SEUH 2022), 2022) Dick, Steffen; Schulz, Stefan; Bockisch, Christoph
    Awareness of software quality is a skill generally agreed to be very important working in the industry, but we have observed that it receives little attention in the first-year programming education at universities. Besides preparing students for work life, we assume that good knowledge of software quality also helps computer science students to study more successfully. In this paper, we present a method for determining the quality-awareness, based on a diagnostic assignment and a questionnaire. Using the method we establish a baseline measurement in two courses that students typically follow in their first year, showing that quality awareness correlates with good grades. According to the baseline, the level of quality-mindedness of approximately half the students is not satisfactory.