Ausgabe (Heft) zu einer Zeitschrift
Filtern
Erscheinungsjahr
Dokumenttyp
- Ausgabe (Heft) zu einer Zeitschrift (354) (entfernen)
Sprache
- Deutsch (269)
- Englisch (84)
- Mehrsprachig (1)
Schlagworte
- Vorlesungsverzeichnis (55)
- Forschen in Koblenz (7)
- Junges Forschen (7)
- Wissenschaft Koblenz (7)
- Bluetooth (4)
- computer clusters (4)
- ontology (4)
- Knowledge Compilation (3)
- Petri-Netze (3)
- parallel algorithms (3)
Institut
- Zentrale Einrichtungen (171)
- Fachbereich 4 (132)
- Institut für Informatik (38)
- Institut für Wirtschafts- und Verwaltungsinformatik (35)
- Institut für Management (31)
- Institute for Web Science and Technologies (15)
- Institut für Computervisualistik (12)
- Institut für Anglistik und Amerikanistik (7)
- Institut für Evangelische Theologie (7)
- Institut für Kulturwissenschaft (7)
- Institut für Softwaretechnik (6)
- Fachbereich 5 (5)
- Institut für Erziehungswissenschaft (4)
- Fachbereich 7 (1)
- Institut für Pädagogik, Abteilung Schulpädagogik/Allgemeine Didaktik (1)
Sustainable Leadership
(2023)
Thematik:
Die vorliegende Forschungsarbeit befasst sich mit dem Thema Sustainable Leadership. Dieses Forschungsgebiet der nachhaltigkeitsorientierten Forschung hat in den letzten Jah- ren durch die immer stärker werden Auswirkungen des Klimawandels erheblich an Bedeutung gewonnen. In diesem Zusammenhang rücken Unternehmen immer mehr in den Fokus. Diese müssen nun Wege und Methoden finden, die ihre Arbeitsweise und Prozesse nachhaltiger und umweltschonender gestalten. Die in der vorliegenden Arbeit zu untersuchende Forschungsfrage lautet: „Wie gestaltet sich ein Sustainable Leadership Ansatz in Unternehmen?“ Aufbauend auf dieser übergeordneten Forschungsfrage werden in untergeordneten Forschungsfrage insbesondere Merkmale, Kompetenzen und Verhaltensweisen eines nachhaltigkeitsorientierten Führungsstils betrachtet.
Methodik:
Die Forschungsmethodik der vorliegenden Arbeit ist eine qualitative Inhaltsanalyse nach Mayring (2019). Mittels semistrukturierter Interviews wurden Führungspersönlichkeiten aus Großunternehmen befragt. Auf Grundlage dieses Datenmaterials wurden induktive Kategorien abgeleitet und qualitativ analysiert und interpretiert.
Ergebnisse:
Die Ergebnisse der empirischen Forschung wurden in insgesamt fünf Oberkategorien mit jeweils zwei Unterkategorien zusammengefasst. Es wurden die theoretischen Erkennt- nisse des Forschungsbereichs mit den praktischen Erkenntnissen aus den durchgeführten Interviews ergänzt und interpretiert. Des Weiteren wurden die Ergebnisse aus Sicht einer holistischen Unternehmensperspektive in einem konzeptionellen Ansatz modelliert. Ab- schließend wurden aus den Praxiserfahrungen einige Handlungsempfehlungen formuliert und die Merkmale, Kompetenzen, Verhaltensweisen und Auswirkungen eines nachhal- tigkeitsorientierten Führungsstils diskutiert.
Querying for meta knowledge
(2008)
The Semantic Web is based on accessing and reusing RDF data from many different sources, which one may assign different levels of authority and credibility. Existing Semantic Web query languages, like SPARQL, have targeted the retrieval, combination and reuse of facts, but have so far ignored all aspects of meta knowledge, such as origins, authorship, recency or certainty of data, to name but a few. In this paper, we present an original, generic, formalized and implemented approach for managing many dimensions of meta knowledge, like source, authorship, certainty and others. The approach re-uses existing RDF modeling possibilities in order to represent meta knowledge. Then, it extends SPARQL query processing in such a way that given a SPARQL query for data, one may request meta knowledge without modifying the query proper. Thus, our approach achieves highly flexible and automatically coordinated querying for data and meta knowledge, while completely separating the two areas of concern.
Absicht: Die vorliegende Forschungsarbeit soll einerseits ein Grundverständnis zu Herausforderungen von jungen Unternehmen, die sich im Wachstum befinden, herstellen, indem bisherige Erkenntnisse zu diesem Thema diskutiert werden. Andererseits möchte dieses Forschungsprojekt durch die theoriegeleitete Untersuchung eines Fallbeispiels neue Erkenntnisse zu konkreten Herausforderungen und möglichen Lernprozessen generieren.
Design/Methodologie/Vorgehen: Vom Autor dieser Arbeit wird eine theoriegeleitete Case Study Untersuchung durchgeführt. Dabei werden zwei theoretische Ansätze zugrunde gelegt, die das Phänomen um Herausforderungen von Jungunternehmen im Wachstum abstrahiert darstellen sollen: Einerseits das Spannungsbalancierende Management nach Harald von Korflesch, welches die grundsätzliche Spannungsgeladenheit unternehmerischer Organisationen zum Ausdruck bringt, was wiederum als Ausgangspunkt für konkrete Herausforderungen anzusehen ist. Andererseits das Tipping Points Absorbative Capaci ties Framework von Phelps und Kollegen, welches Herausforderungen (Tipping Points), die junge Unternehmen während ihrer Lebensdauer erleben werden, mit benötigten Fähigkeiten (Absorbative Capacities) in Verbindung bringt. Durch diese Theorien geleitet, werden reichhaltige Daten aus Interviews, Observationen und Dokumenten bei dem Fallbeispiel erhoben und analysiert.
Ergebnisse: Herausforderungen von jungen Unternehmen im Wachstum lassen sich einerseits auf übergeordneter Ebene mithilfe der beiden theoretischen Ansätze beschreiben. Andererseits zeigt die Analyse auch, dass vor allem eine feingranulare, individuelle Betrachtung von Nöten ist, um Herausforderungen und Lernprozesse adäquat abzubilden.
Forschungslimitationen: Die größte Limitation der vorliegenden Untersuchung findet sich im Single-Case Design. Dadurch, dass lediglich ein konkretes Fallbeispiel untersucht wurde, lassen sich die daraus gewonnen Erkenntnisse nicht auf automatisch auf vergleichbare Fallbeispiele replizieren. Durch die gleichzeitige Untersuchung mehrerer Cases könnten die Ergebnisse somit haltbarer gemacht werden.
Originalität/Beitrag: Durch die qualitative Untersuchung von Herausforderungen im Wachstum anhand eines konkreten Fallbeispiels wird ein eingehendes und tiefgreifendes Verständnis über komplexe Wirkungszusammenhänge im Wachstum von jungen Unternehmen geschaffen. Darüber hinaus werden die Annahmen der beiden theoretischen Ansätze an einem realen Fallbeispiel getestet, sodass theoretische wie praktische Implikationen identifiziert werden können.
In recent years, traceability has been more and more universally accepted as being a key factor for the success of software development projects. However, the multitude of different, not well-integrated taxonomies, approaches and technologies impedes the application of traceability techniques in practice. This paper presents a comprehensive view on traceability, pertaining to the whole software development process. Based on graph technology, it derives a seamless approach which combines all activities related to traceability information, namely definition, recording, identification, maintenance, retrieval, and utilization in one single conceptual framework. The presented approach is validated in the context of the ReDSeeDS-project aiming at requirements-based software reuse.
The way information is presented to users in online community platforms has an influence on the way the users create new information. This is the case, for instance, in question-answering fora, crowdsourcing platforms or other social computation settings. To better understand the effects of presentation policies on user activity, we introduce a generative model of user behaviour in this paper. Running simulations based on this user behaviour we demonstrate the ability of the model to evoke macro phenomena comparable to the ones observed on real world data.
In dieser Bachelorarbeit wird eine Datenbank für weltweite Eisenbahn-Unfalluntersuchungsstellen erstellt. Sie beinhaltet Kontaktdaten zu jenen Behörden als auch Angaben zu öffentlich gestellten Unfalluntersuchungsberichten. Die Datenbank soll als Grundlage zur Informations- und Datenbeschaffung von Eisenbahnunfällen dienen. Die Angaben, die aus Untersuchungsberichten entnommen werden können, sind wichtige Bestandteile für eine mögliche Bewertung der Wirtschaftlichkeit und Effizienz von Sicherheitstechnologien. Neben den Grundlagen zu Untersuchungsstellen, Untersuchungsberichten und der Effizienzberechnung von Sicherheitstechnologien wird in dieser Arbeit auch eine Auswertung der in der Datenbank vorhandenen Untersuchungsstellen und den gefundenen Untersuchungsberichten präsentiert. Ebenfalls wird der Nutzen der Datenbank von Unfalluntersuchungsstellen erläutert und die möglichen Auswirkungen auf die Eisenbahnsicherheit näher gebracht.
Cloud Computing is a topic that has gained momentum in the last years. Current studies show that an increasing number of companies is evaluating the promised advantages and considering making use of cloud services. In this paper we investigate the phenomenon of cloud computing and its importance for the operation of ERP systems. We argue that the phenomenon of cloud computing could lead to a decisive change in the way business software is deployed in companies. Our reference framework contains three levels (IaaS, PaaS, SaaS) and clarifies the meaning of public, private and hybrid clouds. The three levels of cloud computing and their impact on ERP systems operation are discussed. From the literature we identify areas for future research and propose a research agenda.
Knowledge compilation is a common technique for propositional logic knowledge bases. A given knowledge base is transformed into a normal form, for which queries can be answered efficiently. This precompilation step is expensive, but it only has to be performed once. We apply this technique to concepts defined in the Description Logic ALC. We introduce a normal form called linkless normal form for ALC concepts and discuss an efficient satisability test for concepts given in this normal form. Furthermore, we will show how to efficiently calculate uniform interpolants of precompiled concepts w.r.t. a given signature.
In this paper, we compare two approaches for exploring large,rnhierarchical data spaces of social media data on mobile devicesrnusing facets. While the first approach arranges thernfacets in a 3x3 grid, the second approach makes use of arnscrollable list of facets for exploring the data. We have conductedrna between-group experiment of the two approachesrnwith 24 subjects (20 male, 4 female) executing the same set ofrntasks of typical mobile users" information needs. The resultsrnshow that the grid-based approach requires significantly morernclicks, but subjects need less time for completing the tasks.rnFurthermore, it shows that the additional clicks do not hamperrnthe subjects" satisfaction. Thus, the results suggest thatrnthe grid-based approach is a better choice for faceted searchrnon touchscreen mobile devices. To the best of our knowledge,rnsuch a summative evaluation of different approaches for facetedrnsearch on mobile devices has not been done so far.
Railway safety is a topic which gains the public attention only if major railway accidents happen. This is because railway is considered as a safe mode of travel by the public. However, to ensure the safety of the railway system railway companies as well as universities conduct a broad spectrum of research. An overview of this research has not yet been provided in the scholarly literature. Therefore, this thesis follows two objectives. First an overview and ranking of railway safety research universities should be provided. Second, based on these universities, it should be identified which are the most relevant and influential research topics. The ranking is based on the research method “literature review” which forms the methodical basis for this thesis. To evaluate the universities based on a measurable and objective criterion, the number of citations of the researchers from each university is gathered. As a result, the University of Leuven for the civil engineering, Milan Politechnico for mechanical enginering and the University of Loughborough for electrical engineering are identified as the leading university in their field of railway safety research. The top universities for each discipline are distributed all over Europe, North America and Asia. However, a clear focus on the US and British universities is observed. For identification of the most relevant and influential topics the keywords from the publications which are considered in the ranking procedure are analyzed. Focus areas among these keywords are revealed by calculating the count of each keyword. High-speed trains as well as maintenance are recognized as the highly relevant topics in both civil and mechanical engineering. Furthermore, the topic of railway dynamics for mechanical engineering and noise and vibration for civil engineering are identified as the leading topics in the respective discipline. Achieving both research goals required exploratory approaches. Therefore, this thesis leaves open space for future research to deepen the individual topics which are approached in each section. A validation of the results through experts interviews as well as a deepening of the analysis through increasing the number of analyzed universities as well as applying statistical methods is recommended.
We propose a new approach for mobile visualization and interaction of temporal information by integrating support for time with today's most prevalent visualization of spatial information, the map. Our approach allows for an easy and precise selection of the time that is of interest and provides immediate feedback to the users when interacting with it. It has been developed in an evolutionary process gaining formative feedback from end users.
Designing Core Ontologies
(2011)
One of the key factors that hinders integration of distributed, heterogeneous information systems is the lack of a formal basis for modeling the complex, structured knowledge that is to be exchanged. To alleviate this situation, we present an approach based on core ontologies. Core ontologies are characterized by a high degree of axiomatization and formal precision. This is achieved by basing on a foundational ontology. In addition, core ontologies should follow a pattern-oriented design approach. By this, they are modular and extensible. Core ontologies allow for reusing the structured knowledge they define as well as integrating existing domainrnknowledge. The structured knowledge of the core ontologies is clearly separated from the domain-specific knowledge. Such core ontologies allow for both formally conceptualize their particular fields and to be flexibly combined to cover the needsrnof concrete, complex application domains. Over the last years, we have developed three independent core ontologies for events and objects, multimedia annotations, and personal information management. In this paper, we present the simultaneousrnuse and integration of our core ontologies at the example of a complex, distributed socio-technical system of emergency response. We describe our design approach for core ontologies and discuss the lessons learned in designing them. Finally, we elaborate on the beauty aspects of our core ontologies.
Schema information about resources in the Linked Open Data (LOD) cloud can be provided in a twofold way: it can be explicitly defined by attaching RDF types to the resources. Or it is provided implicitly via the definition of the resources´ properties.
In this paper, we analyze the correlation between the two sources of schema information. To this end, we have extracted schema information regarding the types and properties defined in two datasets of different size. One dataset is a LOD crawl from TimBL- FOAF profile (11 Mio. triple) and the second is an extract from the Billion Triples Challenge 2011 dataset (500 Mio. triple). We have conducted an in depth analysis and have computed various entropy measures as well as the mutual information encoded in this two manifestations of schema information.
Our analysis provides insights into the information encoded in the different schema characteristics. It shows that a schema based on either types or properties alone will capture only about 75% of the information contained in the data. From these observations, we derive conclusions about the design of future schemas for LOD.
The lack of a formal event model hinders interoperability in distributed event-based systems. Consequently, we present in this paper a formal model of events, called F. The model bases on an upper-level ontology and pro-vides comprehensive support for all aspects of events such as time and space, objects and persons involved, as well as the structural aspects, namely mereological, causal, and correlational relationships. The event model provides a flexible means for event composition, modeling of event causality and correlation, and allows for representing different interpretations of the same event. The foundational event model F is developed in a pattern-oriented approach, modularized in different ontologies, and can be easily extended by domain specifific ontologies.
The Multimedia Metadata Ontology (M3O) provides a generic modeling framework for representing multimedia metadata. It has been designed based on an analysis of existing metadata standards and metadata formats. The M3O abstracts from the existing metadata standards and formats and provides generic modeling solutions for annotations, decompositions, and provenance of metadata. Being a generic modeling framework, the M3O aims at integrating the existing metadata standards and metadata formats rather than replacing them. This is in particular useful as today's multimedia applications often need to combine and use more than one existing metadata standard or metadata format at the same time. However, applying and specializing the abstract and powerful M3O modeling framework in concrete application domains and integrating it with existing metadata formats and metadata standards is not always straightforward. Thus, we have developed a step-by-step alignment method that describes how to integrate existing multimedia metadata standards and metadata formats with the M3O in order to use them in a concrete application. We demonstrate our alignment method by integrating seven different existing metadata standards and metadata formats with the M3O and describe the experiences made during the integration process.
Networked RDF graphs
(2007)
Networked graphs are defined in this paper as a small syntactic extension of named graphs in RDF. They allow for the definition of a graph by explicitly listing triples as well as by SPARQL queries on one or multiple other graphs. By this extension it becomes possible to define a graph including a view onto other graphs and to define the meaning of a set of graphs by the way they reference each other. The semantics of networked graphs is defined by their mapping into logic programs. The expressiveness and computational complexity of networked graphs, varying by the set of constraints imposed on the underlying SPARQL queries, is investigated. We demonstrate the capabilities of networked graphs by a simple use case.
Existing tools for generating application programming interfaces (APIs) for ontologies lack sophisticated support for mapping the logics-based concepts of the ontology to an appropriate object-oriented implementation of the API. Such a mapping has to overcome the fundamental differences between the semantics described in the ontology and the pragmatics, i.e., structure, functionalities, and behavior implemented in the API. Typically, concepts from the ontology are mapped one-to-one to classes in the targeted programming language. Such a mapping only produces concept representations but not an API at the desired level of granularity expected by an application developer. We present a Model-Driven Engineering (MDE) process to generate customized APIs for ontologies. This API generation is based on the semantics defined in the ontology but also leverages additional information the ontology provides. This can be the inheritance structure of the ontology concepts, the scope of relevance of an ontology concept, or design patterns defined in the ontology.
Modeling and publishing Linked Open Data (LOD) involves the choice of which vocabulary to use. This choice is far from trivial and poses a challenge to a Linked Data engineer. It covers the search for appropriate vocabulary terms, making decisions regarding the number of vocabularies to consider in the design process, as well as the way of selecting and combining vocabularies. Until today, there is no study that investigates the different strategies of reusing vocabularies for LOD modeling and publishing. In this paper, we present the results of a survey with 79 participants that examines the most preferred vocabulary reuse strategies of LOD modeling. Participants of our survey are LOD publishers and practitioners. Their task was to assess different vocabulary reuse strategies and explain their ranking decision. We found significant differences between the modeling strategies that range from reusing popular vocabularies, minimizing the number of vocabularies, and staying within one domain vocabulary. A very interesting insight is that the popularity in the meaning of how frequent a vocabulary is used in a data source is more important than how often individual classes and properties arernused in the LOD cloud. Overall, the results of this survey help in understanding the strategies how data engineers reuse vocabularies, and theyrnmay also be used to develop future vocabulary engineering tools.
Die folgende Arbeit soll einen Überblick über bestehende Lösungen zur Interaktion in Erweiterten Realitäten (Augmented Reality) schaffen. Hierzu werden anhand dreier grundlegender Betrachtungsweisen unterschiedliche Interaktionskonzepte und -umsetzungen sowohl von der technischen, als auch von der konzeptuellen Seite her, vorgestellt. Neben Fragen der Visualisierung werden unterschiedliche Typen von Benutzungsschnittstellen vorstellt. Den größten Teil nehmen die drei typischen Interaktionsaufgaben Selektion- und Manipulation, Navigation und Systemkontrolle und die damit verbundenen Interaktionstechniken ein. Die Inhalte des Arbeitsberichts beschränken sich auf den Einsatz von Interaktionelementen in Augmented Reality Umgebungen. Dies geschieht in Abgrenzung zu Forschungsarbeiten auf dem Gebiet zu Interaktionstechniken in Virtual Reality Umgebungen (vollimmersiv oder auch desktoporientiert). Zwar standen und stehen viele Interaktionstechniken aus dem Bereich VR in der AR Pate, doch haben sich gerade im Bereich der AR neue Techniken und Konzepte entwickelt. Folglich sollen VR Techniken nur dann betrachtet werden, wenn Sie in AR Anwendungen angewendet wurden bzw. wenn ihre Anwendung sinnvoll erscheint.