Fachbereich 4
Refine
Year of publication
Document Type
- Part of Periodical (104)
- Bachelor Thesis (66)
- Diploma Thesis (47)
- Master's Thesis (32)
- Study Thesis (9)
- Conference Proceedings (5)
Keywords
- Simulation (5)
- Bluetooth (4)
- ontology (4)
- Android <Systemplattform> (3)
- Augmented Reality (3)
- Customer Relationship Management (3)
- Enterprise 2.0 (3)
- Informatik (3)
- Knowledge Compilation (3)
- Mikrocontroller AVR (3)
Institute
- Fachbereich 4 (263)
- Institut für Informatik (27)
- Institut für Wirtschafts- und Verwaltungsinformatik (26)
- Institute for Web Science and Technologies (13)
- Institut für Computervisualistik (9)
- Institut für Management (9)
- Institut für Softwaretechnik (3)
- Institut für Integrierte Naturwissenschaften (1)
Information systems research has started to use crowdsourcing platforms such as Amazon Mechanical Turks (MTurk) for scientific research, recently. In particular, MTurk provides a scalable, cheap work-force that can also be used as a pool of potential respondents for online survey research. In light of the increasing use of crowdsourcing platforms for survey research, the authors aim to contribute to the understanding of its appropriate usage. Therefore, they assess if samples drawn from MTurk deviate from those drawn via conventional online surveys (COS) in terms of answers in relation to relevant e-commerce variables and test the data in a nomological network for assessing differences in effects.
The authors compare responses from 138 MTurk workers with those of 150 German shoppers recruited via COS. The findings indicate, inter alia, that MTurk workers tend to exhibit more positive word-of mouth, perceived risk, customer orientation and commitment to the focal company. The authors discuss the study- results, point to limitations, and provide avenues for further research.
Der Fachbereich 4 (Informatik) besteht aus fünfundzwanzig Arbeitsgruppen unter der Leitung von Professorinnen und Professoren, die für die Forschung und Lehre in sechs Instituten zusammenarbeiten.
In jedem Jahresbericht stellen sich die Arbeitsgruppen nach einem einheitlichen Muster dar, welche personelle Zusammensetzung sie haben, welche Projekte in den Berichtszeitraum fallen und welche wissenschaftlichen Leistungen erbracht wurden. In den folgenden Kapiteln werden einzelne Parameter aufgeführt, die den Fachbereich in quantitativer Hinsicht, was Drittmitteleinwerbungen, Abdeckung der Lehre, Absolventen oder Veröffentlichungen angeht, beschreiben.
The aim of this paper is to identify and understand the risks and issues companies are experiencing from the business use of social media and to develop a framework for describing and categorising those social media risks. The goal is to contribute to the evolving theorisation of social media risk and to provide a foundation for the further development of social media risk management strategies and processes. The study findings identify thirty risk types organised into five categories (technical, human, content, compliance and reputational). A risk-chain is used to illustrate the complex interrelated, multi-stakeholder nature of these risks and directions for future work are identified.
Im Laufe der letzten Jahre hat sich der typische Komplex an kritischen Erfolgsfaktoren für Unternehmen verändert, infolgedessen der Faktor Wissen eine wachsende Bedeutung erlangt hat. Insofern kann man zum heutigen Zeitpunkt von Wissen als viertem Produktionsfaktor sprechen, welcher die Faktoren Arbeit, Kapital und Boden als wichtigste Faktoren eines Unternehmens ablöst (vgl. Keller & Yeaple 2013, S. 2; Kogut & Zander 1993, S. 631). Dies liegt darin begründet, dass aktive Maßnahmen zur Unterstützung von Wissenstransfer in Unternehmen höhere Profite und Marktanteile sowie bessere Überlebensfähigkeit gegenüber Wettbewerbern ohne derartige Maßnahmen nach sich ziehen (vgl. Argote 1999, S. 28; Szulanski 1996, S. 27; Osterloh & Frey 2000, S. 538). Der hauptsächliche Vorteil von wissensbasierten Entwicklungen liegt dabei in deren Nachhaltigkeit, da aufgrund der immateriellen Struktur (vgl. Inkpen & Dinur 1998, S. 456; Spender 1996a, S. 65 f.; Spender 1996b, S. 49; Nelson & Winter 1982, S. 76 ff.) eine Nachahmung durch Wettbewerber erschwert wird (vgl. Wernerfelt 1984, S. 173; Barney 1991, S. 102).
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.
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.
Remote rendering services offer the possibility to stream high quality images to lower powered devices. Due to the transmission of data the interactivity of applications is afflicted with a delay. A method to reduce delay of the camera manipulation on the client is called 3d-warping. This method causes artifacts. In this thesis different approaches of remote rendering setups will be shown. The artifacts and improvements of the warping method will be described. Methods to reduce the artifacts will be implemented and analyzed.
Aufgrund des branchenweiten Bedarfs den Konkurrenzkampf zu umgehen, entwickelten Kim und Mauborgne die Blue Ocean Strategy, um neue Märkte zu ergründen. Diese bezeichnen sie als einzigartig. Da jedoch weitere Strategien zur Ergründung neuer Märkte existieren, ist es das Ziel dieser Arbeit herauszufinden, anhand welcher Charakterisierungsmerkmale die Blue Ocean Strategy als einzigartig angesehen werden kann.
Die Strategie von Kim und Mauborgne soll daher mit Schumpeters schöpferischen Zerstörung, Ansoffs Diversifikationsstrategie, Porters Nischenstrategie und Druckers Innovationsstrategien verglichen werden. Für den Vergleich werden die Charakterisierungsmerkmale herangezogen, nach denen Kim und Mauborgne die Blue Ocean Strategy als einzigartig beurteilen. Auf Basis dieser Kriterien wird ein Metamodell entwickelt, mit dessen Hilfe die Untersuchung durchgeführt wird.
Der Vergleich zeigt, dass die Konzepte von Schumpeter, Ansoff, Porter und Drucker in einigen Kriterien der Blue Ocean Strategy ähneln. Keine der Strategien verhält sich jedoch in allen Punkten so wie das Konzept von Kim und Mauborgne. Während die Blue Ocean Strategy ein Differenzierung und Senkung der Kosten anstrebt, orientieren sich die meisten Konzepte entweder an einer Differenzierung oder an einer Kostenreduktion. Auch die Betretung des neuen Marktes wird unterschiedlich interpretiert. Während die Blue Ocean Strategy auf einen Markt abzielt, der unergründet ist und somit keinen Wettbewerb vorweist, werden bei den anderen Strategien oft bestehende Märkte als neu interpretiert, auf denen das Unternehmen bisher nicht agiert hat. Dies schließt die vorherige Existenz der Märkte jedoch nicht aus.
Auf Basis der durch den Vergleich gezogenen Erkenntnisse, kann somit die Blue Ocean Strategy als einzigartig bezeichnet werden.
Data Mining im Fußball
(2014)
The term Data Mining is used to describe applications that can be applied to extract useful information from large datasets. Since the 2011/2012 season of the german soccer league, extensive data from the first and second Bundesliga have been recorded and stored. Up to 2000 events are recorded for each game.
The question arises, whether it is possible to use Data Mining to extract patterns from this extensive data which could be useful to soccer clubs.
In this thesis, Data Mining is applied to the data of the first Bundesliga to measure the value of individual soccer players for their club. For this purpose, the state of the art and the available data are described. Furthermore, classification, regression analysis and clustering are applied to the available data. This thesis focuses on qualitative characteristics of soccer players like the nomination for the national squad or the marks players get for their playing performance. Additionally this thesis considers the playing style of the available players and examines if it is possible to make predictions for upcoming seasons. The value of individual players is determined by using regression analysis and a combination of cluster analysis and regression analysis.
Even though not all applications can achieve sufficient results, this thesis shows that Data Mining has the potential to be applied to soccer data. The value of a player can be measured with the help of the two approaches, allowing simple visualization of the importance of a player for his club.
Systems to simulate crowd-behavior are used to simulate the evacuation of a crowd in case of an emergency. These systems are limited to the moving-patterns of a crowd and are generally not considering psychological and/or physical conditions. Changing behaviors within the crowd (e.g. by a person falling down) are not considered.
For that reason, this thesis will examine the psychological behavior and the physical impact of a crowd- member on the crowd. In order to do so, this study develops a real-time simulation for a crowd of people, adapted from a system for video games. This system contains a behavior-AI for agents. In order to show physical interaction between the agents and their environment as well as their movements, the physical representation of each agent is realized by using rigid bodies from a physics-engine. The movements of the agents have an additional navigation mesh and an algorithm for collision avoidance.
By developing a behavior-AI a physical and psychological state is reached. This state contains a psychological stress-level as well as a physical condition. The developed simulation is able to show physical impacts such as crowding and crushing of agents, interaction of agents with their environment as well as factors of stress.
By evaluating several tests of the simulation, this thesis examines whether the combination of physical and psychological impacts is implementable successfully. If so, this thesis will be able to give indications of an agent- behavior in dangerous and/or stressful situations as well as a valuation of the complex physical representation.
Ziel dieser Ausarbeitung ist es, das Wippe-Experiment gemäß dem Aufbau innerhalb der AG Echtzeitsysteme unter Leitung von Professor Dr. Dieter Zöbel mithilfe eines LEGO Mindstorms NXT Education-Bausatzes funktionsfähig nachzubauen und das Vorgehen zu dokumentieren. Der dabei entstehende Programmcode soll didaktisch aufbereitet und eine Bauanleitung zur Verfügung gestellt werden. Dies soll gewährleisten, dass Schülerinnen und Schüler auch ohne direkten Zugang zu einer Hochschule oder ähnlichem Institut den Versuchsaufbau Wippe möglichst unkompliziert im Klassenraum erleben können.
Die Arbeit stellt Path Tracing zum Rendern von Bildern mitrnglobaler Beleuchtung vor. Durch die Berechnung der Rendergleichung, mithilfe von Zufallsexperimenten, ist das Verfahren physikalisch plausibel. Entscheidend für die Qualität der Ergebnisse ist Sampling. Der Schwerpunktrnder Arbeit ist die Untersuchung verschiedener Samplingstrategien. Dazu werden die Ergebnisse unterschiedlicher Dichtefunktionen verglichenrnund die Methoden bewertet. Außerdem werden Effekte, wie beispielsweise Depth of Field, mittels Sampling visualisiert.
Im Rahmen des "Design Thinking"-Prozesses kommen unterschiedliche Varianten kreativitätsfördernder Techniken zum Einsatz. Aufgrund der zunehmenden Globalisierung ergeben sich immer häufiger Kollaborationen, bei denen sich die jeweiligen Projektteilnehmer an verteilten Standorten befinden. Somit erweist sich die Digitalisierung des Design-Prozesses als durchaus erstrebenswert. Ziel der hier vorliegenden Untersuchung ist daher die Erstellung eines Bewertungsschemas, welches die Eignung digitaler Kreativitätstechniken in Bezug auf das "Entrepreneurial Design Thinking" misst. Des Weiteren soll geprüft werden, inwiefern sich der Einsatz von e-Learning-Systemen in Kombination mit der Verwendung digitaler Kreativitätstechniken eignet. Diese Prüfung soll am Beispiel der e-Learning Software "WebCT" konkretisiert werden. Hieraus ergibt sich die folgende Fragestellung: Welche digitalen Kreativitätstechniken eignen sich für die Anwendung im Bereich des "Entrepreneurial Design Thinkings" unter Einsatz der e-Learning Plattform "WebCT"? Zunächst wird eine Literaturanalyse bezüglich des "Entrepreneurial Design Thinkings", der klassische und digitale Kreativitätstechniken sowie des Arbeitens in Gruppen, was auch das Content Management, e-Learning-Systeme und die Plattform "WebCT" beinhaltet, durchgeführt. Im Anschluss daran wird eine qualitative Untersuchung durchgeführt. Auf Basis bereits bestehender Literatur, soll ein Bewertungsschema erstellt werden, welches misst, welche der behandelten digitalen Kreativitätstechniken für den Einsatz im "Entrepreneurial Design Thinking" am besten geeignet ist. Darauf aufbauend erfolgt die Verknüpfung des digitalisierten "Design Thinking"-Prozesses mit der e-Learning Plattform "WebCT". Abschließend wird diskutiert, in wie fern diese Zusammenführung als sinnvoll erachtet werden kann.
This paper presents a method for the evolution of SHI ABoxes which is based on a compilation technique of the knowledge base. For this the ABox is regarded as an interpretation of the TBox which is close to a model. It is shown, that the ABox can be used for a semantically guided transformation resulting in an equisatisfiable knowledge base. We use the result of this transformation to effciently delete assertions from the ABox. Furthermore, insertion of assertions as well as repair of inconsistent ABoxes is addressed. For the computation of the necessary actions for deletion, insertion and repair, the E-KRHyper theorem prover is used.
Die vorliegende Arbeit befasst sich mit der volkswirtschaftlichen Untersuchung von Arbeit in virtuellen Welten und hat als Kerninhalt die Analyse des Arbeitsmarktes in "Massively Multiplayer Online Role-Playing Games" (MMORPGs). Als Ausgangsbasis diente zum einen der Faktor Arbeit in der Realität, zum anderen wurden zusätzliche Besonderheiten von MMORPGs in die Betrachtung miteinbezogen, woraus sich ein Gesamtbild des virtuellen Arbeitsmarkts ergab, aus dem sich relevante Indikatoren ableiten ließen. Neben dem grundsätzlichen Befund der Existenz eines virtuellen Arbeitsmarktes, wurden Ähnlichkeiten zum realen Arbeitsmarkt deutlich. So war es möglich virtuelle Stundenlöhne zu berechnen, unternehmensähnliche Strukturen in Spielergruppierungen nachzuweisen und ausgehend von der Humankapitaltheorie, eine modifizierte Theorie ("Avatarkapital") für virtuelle Welten zu ermitteln. Allerdings ergaben sich auch Unterschiede, so ist die Komplexität der Herstellungsprozesse in den untersuchten MMORPGs in der Regel weitaus geringer als in der Realität. Durch eine Gegenüberstellung von Motivationsfaktoren in beiden Arbeitswelten wurden weiterhin Gemeinsamkeiten, aber auch Unterschiede festgestellt und dargelegt. Zusätzlich wurde aufgezeigt, dass das aktuell diskutierte Thema Mindestlohn auch in virtuellen Arbeitsmärkten von MMORPGs anzutreffen ist und als Spielmechanik implementiert wurde, um Motivation durch andauernde Beschäftigung zu gewährleisten. Über diese Parallelen hinaus, wurde anhand einer Analyse von Waren- und Geldtransaktionen (Real-Money-Trading) zwischen Virtualität und Realität eine Verbindung beider Welten nachgewiesen, die beide Arbeitsmärkte gleichermaßen betrifft. Neben der theoretischen Untersuchung, war es auch Ziel eigene Beobachtungen und Ansätze in die Ergebnisse einfließen zu lassen. Besonders in der abschließenden empirischen Untersuchung war es somit möglich weitere Faktoren zu entdecken, die nicht ausreichend aus der Theorie heraus zu ermitteln waren. Vor allem weitere Erkenntnisse zum Thema Produktivitätsmessung in virtuellen Welten konnten so aus der Praxis in die Theorie einfließen. Schlussendlich wurde aber auch deutlich, dass sich die Untersuchungen zum Thema Arbeitsmarkt in virtuellen Welten noch in einem frühen Stadium befinden und zahlreiche Forschungsobjekte in diesem Bereich existieren, die mit Sicherheit zu einem Erkenntnisgewinn in der Volkswirtschaftslehre führen.
The Microsoft Kinect is currently polular in many application areas because ofrnthe cheap price and good precission. But controlling the cursor is unapplicablerndue to jitter in the skeletton data. My approach will try to stabilisize the cursor position with common techniques from image processing. The input therefore will be the Kinect color camera. A final position will be calculated using the different positions of the tracking techniques. For controlling the cursor the right hand should be tracked. A simple click gesture will also be developed. The evaluation will show if this approach was succesfull.
ERP market analysis
(2013)
Der aktuelle ERP Markt wird dominiert von den fünf größten Anbietern SAP, Oracle, Microsoft, Infor und Sage. Da der Markt und die angebotenen Lösungen vielfältig sind, bedarf es einer fundierten Analyse der Systeme. Die Arbeit beleuchtet dabei anhand ausgesuchter Literatur und Kennzahlen der verschiedenen Unternehmen die theoretische Seite der angebotenen Lösungen der fünf großen ERP Anbieter. Daneben wird die Nutzung der Systeme in der Praxis anhand der Befragung von sechs Anwendern analysiert und die Systeme miteinander verglichen.
Ziel der Arbeit ist es, dass die Forschungsfragen beantwortet werden und dass es bezogen auf die Systeme dem Leser der Arbeit ersichtlich wird, welches ERP System für welche Unternehmensbranche und Unternehmensgröße am besten geeignet ist.
Des Weiteren gibt die Arbeit Aufschluss darüber, welche Trends für ERP Systeme für die Zukunft zu erwarten sind und welche Herausforderungen sich dadurch für die Unternehmen stellen.
Polsearchine: Implementation of a policy-based search engine for regulating information flows
(2013)
Many search engines regulate Internet communication in some way. It is often difficult for end users to notice such regulation, as well as obtaining background information for it. Additionally, the regulation can usually be circumvented easily. This bachelor thesis presents the prototypical metasearch engine "Polsearchine" for addressing these weaknesses. Its regulation is established through InFO, a model for regulating information flows developed by Kasten and Scherp. More precisely, the extension for regulating search engines SEFCO is being used. For retrieving search results, Polsearchine uses an external search engine API. The API can be interchanged easily to make this metasearch engine independent from one specific API.
Die weltweite Zugänglichkeit und umfangreiche Nutzung des Internets machen dieses Medium zu einem effizienten und beliebten Informations-, Kommunikations-, und Verkaufsinstrument. Immer mehr Menschen und Organisationen versuchen, diese Vorzüge durch eine eigene Website für ihre Zwecke zu verwenden. Als hilfreiches Mittel zur Optimierung von Webpräsenzen bewährte sich in den letzten Jahren der Einsatz von Web-Analytics-Software. Durch diese Software sind Websitebetreiber in der Lage, Informationen über die Besucher ihrer Website und deren Nutzungsverhalten zu sammeln und zu messen. Das angestrebte Resultat sind Optimierungsentscheidungen auf Basis von Daten an Stelle von Annahmen und wirkungsvolle Testmöglichkeiten.
Für den Bereich des E-Commerce existieren bis dato zahlreiche wissenschaftliche und praxiserprobte Hilfestellungen für Web-Analytics-Projekte. Informationswebsites hingegen werden trotz ihrer Wichtigkeit nur vereinzelt thematisiert. Um diesem Defizit entgegenzuwirken, hat Hausmann 2012 das Framework for Web Analytics entwickelt, welches dem Anwender ein hilfreiches Referenzmodell für sein Web Analytics-Vorhaben bietet. Diesen Ansatz weiter voranzutreiben ist das Ziel der Abschlussarbeit. Dazu wird mithilfe einer Literaturanalyse und einer Fallstudie das Framework validiert und ergänzt, sowie weitere Handlungsempfehlungen identifiziert. Als Ergebnis werden die wichtigsten Erkenntnisse dieser Forschung zusammengefasst und für den zukünftigen Gebrauch festgehalten.
Large amounts of qualitative data make the utilization of computer-assisted methods for their analysis inevitable. In this thesis Text Mining as an interdisciplinary approach, as well as the methods established in the empirical social sciences for analyzing written utterances are introduced. On this basis a process of extracting concept networks from texts is outlined and the possibilities of utilitzing natural language processing methods within are highlighted. The core of this process is text processing, to whose execution software solutions supporting manual as well as automated work are necessary. The requirements to be met by these solutions, against the background of the initiating project GLODERS, which is devoted to investigating extortion racket systems as part of the global fiσnancial system, are presented, and their fulσlment by the two most preeminent candidates reviewed. The gap between theory and pratical application is closed by a prototypical application of the method to a data set of the research project utilizing the two given software solutions.
In this thesis we discuss the increasingly important routing aggregation and its consequences on avoiding routing loops. As basis for implementation and evaluation I will use the RMTI protocol, developed at the University of Koblenz, which is an evolution of the RFC2453 specified in the Routing Information Protocol version 2. The virtual network environment Virtual Network User Mode Linux (VNUML) is used within this thesis as environment. With VNUML it is possible to operate and evaluate real network scenarios in a virtual environment. The RMTI has already proven its ability to detect topological loops and thereby prevent the formation of these routing loops. In this thesis we will describe the function of the RMTI and then discuss under which circumstances we can use routing aggregation, without it resulting in routing anomalies. In order to implement these changes it is essential to have a deeper understanding of the structure of routing tables, so the construction will be explained using reference to examples. There follows a description of which points have to be changed, in the RMTI in order to avoid loops despite aggregation. In Summary we will evaluate the affect the routing aggregation has on the reorganization ability of the virtual network.
This thesis describes the implementation of a Path-planning algorithm for multi-axle vehicles using machine learning algorithms. For that purpose, a general overview over Genetic Algorithms is given and alternative machine learning algorithms are briefly explained. The software developed for this purpose is based on the EZSystem Simulation Software developed by the AG Echtzeitysteme at the University Koblenz-Landau and a path correction algorithm developed by Christian Schwarz, which is also detailed in this paper. This also includes a description of the vehicle used in these simulations. Genetic Algorithms as a solution for path-planning in complex scenarios are then evaluated based on the results of the developed simulation software and compared to alternative, non-machine learning solutions, which are also shortly presented.
Forwarding loops
(2013)
Today you can find smartphones everywhere. This situation created a hype for Augmented Reality and AR Apps. The big question is: Do these applications provide a real added value? To make AR pratically it is important to add the computational power of a computer to the advantages of AR. An easy and fast way of interaction is essential.
A Poker-Assistance-Software is an ideal test area for an AR Application with real added value. The estimation of the winning probability and a fast automated tracking of the playing cards is the perfect field of investigation.
In this discussion it is interesting to evaluate the added value of AR Applications in common.
Recipients" youtube comments to the five most successful songs of 2011 and 2012 are tested for nostalgic content. These nostalgic relevant comments are analyzed by content and finally interpreted. It shall be found out, whether nostalgic music content is a factor for success. By using the uses and gratifications theory the recipients" purpose of consuming nostalgic-evoking music will be identified. Music is a clearly stronger trigger for evoking nostalgia than the music video whereas nostalgia triggers positive and/or negative affect. Furthermore personal nostalgia is much more evident than historical nostalgia. Moreover the lyrics have a considerably higher potential to elicit nostalgia than any other song units. Persons and momentous events are the most frequent objects in personal nostalgic reverie. The purpose of consuming nostalgic music is the intended evocation of positive and/or negative affect. Hence nostalgia in music seems to satisfy certain needs and it can be assumed that nostalgia is a factor of success in music industry.
Infinite worlds
(2013)
This work is concerned with creating a 2D action-adventure with roleplay elements. It provides an overview over various tasks of the implementation. First, the game idea and the used gamemechanism are verified and a definfinition of requirements is created. After introducing the used framework, the software engineering concept for realization is presented. The implementation of control components, game editor, sound and graphics is shown. The graphical implementation pays special attention to the abstraction of light and shadow into the 2D game world.
Due to the increasing pervasiveness of the mobile web, it is possible to send and receive mails with mobile devices. Content of digital communication should be encrypted to prevent eavesdropping and manipulation. Corresponding procedures use cryptographic keys, which have to be exchange previously. It has to be ensured, that a cryptographic key really belongs to the person, who it is supposedly assigned to. Within the scope of this thesis a concept for a smartphone application to exchange cryptographic keys was designed. The concept consists of a specification of a component-based framework, which can be used to securely exchange data in general. This framework was extended and used as the basis for a smartphone application. The application allows creating, managing and exchanging cryptographic keys. The Near Field Communication is used for the exchange. Implemented security measures prevent eavesdropping and specific manipulation. In the future the concept and the application can be extended and adjusted to be used in other contexts.
We present the conceptual and technological foundations of a distributed natural language interface employing a graph-based parsing approach. The parsing model developed in this thesis generates a semantic representation of a natural language query in a 3-staged, transition-based process using probabilistic patterns. The semantic representation of a natural language query is modeled in terms of a graph, which represents entities as nodes connected by edges representing relations between entities. The presented system architecture provides the concept of a natural language interface that is both independent in terms of the included vocabularies for parsing the syntax and semantics of the input query, as well as the knowledge sources that are consulted for retrieving search results. This functionality is achieved by modularizing the system's components, addressing external data sources by flexible modules which can be modified at runtime. We evaluate the system's performance by testing the accuracy of the syntactic parser, the precision of the retrieved search results as well as the speed of the prototype.
Geschäftsprozessmanagement (GPM) gilt in der heutigen Unternehmensentwicklung als einer der wichtigsten Erfolgsfaktoren und wird von modernen Unternehmen auch als solcher wahrgenommen [vgl. IDS Scheer 2008]. Bereits 1993 waren Geschäftsprozesse für Hammer und Champy der zentrale Schlüssel zur Reorganisation von Unternehmen [vgl. Hammer, Champy 1993, S. 35]. Den Paradigmenwechsel von der Aufbau- zur Ablauforganisation und letztendlich zur etablierten "Prozessorganisation" wurde von Gaitanides schon 1983 erstmals beschrieben [vgl. Gaitanides 2007].
Trotz einer breiten und tiefen Behandlung des Themengebiets "Geschäftsprozessmanagement" in der wissenschaftlichen Literatur, gestaltet es sich schwierig, einen schnellen Überblick in Bezug auf Vorgehensweisen zur Einführung von Geschäftsprozessmanagement zu erhalten. Dies ist im Wesentlichen der Tatsache geschuldet, dass in der Literatur "Geschäftsprozessmanagement" in unterschiedlichen wissenschaftlichen Bereichen wie z.B. der Organisationslehre [vgl. z.B. Vahs 2009; Schulte-Zurhausen 2005], der Betriebswirtschaft [vgl. z.B. Helbig 2003; Schmidt 2012] oder der Informatik bzw. Wirtschaftsinformatik [vgl. z.B. Schmelzer, Sesselmann 2008; Schwickert, Fischer 1996] behandelt und der Aufbau eines GPMs anhand unterschiedlicher Themenschwerpunkte beschrieben wird. Insbesondere gestaltet sich die Suche nach Literatur zu Geschäftsprozessmanagement speziell für kleine und mittlere Unternehmen (KMU) und zu Einführungsmethoden von BPM in KMU als schwierig. Die Kombination "Vorgehensweisen zur Einführung von Geschäftsprozessmanagement bei KMU" ist in der wissenschaftlichen Literatur nicht aufzufinden. Mit der vorliegenden Arbeit soll ein erster Ansatz geschaffen werden, diese Lücke zu schließen. Diese Arbeit zielt darauf ab, anhand einer Auswahl von Vorgehensweisen zur Einführung von Geschäftsprozessmanagement deren charakteristische Eigenschaften zu analysieren und einander gegenüberzustellen. Zudem erfolgt eine Bewertung auf die Anwendbarkeit einzelner Vorgehensweisen auf kleine und mittlere Unternehmen anhand zuvor erhobener, für KMU wichtiger Anforderungen an BPM und dessen Einführung.
Auf Basis der dieser Arbeit zugrundeliegenden Bewertungskriterien schneidet die Vorgehensweise nach Schulte-Zurhausen im Gesamtergebnis am besten ab. Dennoch ist festzustellen, dass jede der untersuchten Vorgehensweisen Stärken und Schwächen bzgl. der Eignung für ein KMU aufweist. Dies hat zur Folge, dass bei der Einführung eines Geschäftsprozessmanagements jede der untersuchten Vorgehensweisen einer Anpassung und Adaption auf die Situation eines KMUs bedarf. Aus diesem Grund empfiehlt der Autor dieser Arbeit einem KMU, eine Vorgehensweise als grundlegende Vorgehensweise der Einführung festzulegen (in diesem Fall die Vorgehensweise nach Schulte-Zurhausen) und diese durch jeweils geeignete Aspekte der weiteren Vorgehensweisen anzureichern bzw. zu vervollständigen.
Augmented Reality (AR) is getting more and more popular. To augment information into the field of vision of the user using HMDs, e.g. front shields of a car, glasses, displays of a smartphone or tablets are the main use of AR technology. It is necessary to get the position and orientation (pose) of the camera in space to augment correctly.
Nowadays, this is solved with artificial markers. These known markers are placed in the room and the system is taught to this set up. The next step is to get rid of these artificial markers. If we are calculating the pose without such markers we are talking about marker-less tracking. Instead of artificial markers we will use natural objects in the real world as reference points to calculate the pose. Thus, this approach can be used flexibly and dynamically. We are no longer dependent on artificial markers but we need much more knowledge about the scenery to find the pose. This is compensated by technical actions and/or the user himself. However, both solutions are neither comfortable nor efficient for the usage of such a system. This is why marker-less 3D tracking is still a big field of research.
This sets the starting point for the bachelor thesis. In this thesis an approach is proposed that needs only a quantity of 2D Feature from a given camera image and a quantity of 3D Feature of an object to find the initial Pose. With this approach, we got rid of the technical and user assistance. 2D and 3D Features can be detected in any way you like.
The main idea of this approach is to build six correspondences between these quantities. With those we are able to estimate the pose. Each 3D Feature is mapped with the estimated pose onto image coordinates, whereby the estimated pose can be evaluated. Each distance is measured between the mapped 3D Feature and the associated 2D Feature. Each correspondency is evaluated and the results are summed up to evaluate the whole pose. The lower this summed up value is, the better the pose. It has been shown to have a correct pose with a value around ten pixels.
Due to lots of possibilities to build six correspondences between the quantities, it is necessary to optimize the building process. For the optimization we will use a genetic algorithm.
During the test case the system worked quite reliably. The hit rate was around 90% with a runtime of approximately twelve minutes. Without optimization it can take easily some years.
Diese Bachelor-Thesis beschäftigt sich mit der Entwicklung eines Programms, welches den Zahnarzt durch die AR bei seiner Behandlung am Patienten unterstützen soll. Um eine angemessene theoretische Grundlage zu schaffen, wird zunächst der aktuelle Stand der Technik erläutert, der für dieses Projekt relevant ist. Daraufhin werden mögliche zukünftige Technologien vorgestellt, welche die hypothetische Basis dieser Arbeit darstellen. In dem darauffolgenden Unterkapitel wird die Auswahl der Systeme erläutert, die für dieses Projekt verwendet wurden. Der Hauptteil beschäftigt sich zunächst mit dem Vorgehen in der Vorbereitungs- und Planungsphase, um daraufhin den Programmablauf der Applikation sukzessiv vorzustellen. Dabei wird auch auf die Probleme eingegangen, die während des Programmierens entstanden sind. In dem reflektierenden Auswertungsteil werden Verbesserungsvorschlägen und Zusatzfunktionen für das geschriebene Programm präsentiert.
This master thesis deals basically with the design and implementation of a path planning system based on rapidly exploring search trees for general-n-trailers. This is a probabilistic method that is characterized by a fast and uniform exploration. The method is well established, however, has been applied only to vehicles with simple kinematics to date. General-n-trailers represent a particular challenge as their controllability is limited. For this reason the focus of this thesis rests on the application of the mentioned procedure to general-n-trailers. In this context systematic correlations between the characteristics of general-n-trailers and the possibilities for the realization and application of the method are analyzed.
This thesis deals with the development and evaluation of a concept of novel interaction with ubiquitous user interfaces. To accomplish the evaluation of this interaction concept, a prototype was implementated by using an existing head-mounted display solution and an android smartphone.
Furthermore, in the course of this thesis, a concrete use case for this prototype " the navigation through a city block with the aid of an electronic map " was developed and built as an executable application to help evaluate the quality of the interaction concept. Therefore, fundamental research results were achieved.
This bachelor thesis deals with the concept of a smartphone application for emergencies. It describes the basic problem and provides a conceptual approach.
The core content of this thesis is a requirement analysis of the newly to be designed emergency application. Furthermore the functional and non-functional requirements such as usability are specified to give insights for the concept of the application. In addition, single sub-functions of the mHealth applications of the University Koblenz which exists or are still under construction can be integrated in the future emergency application. Based on the catalog of requirements a market analysis for strengths and weaknesses of existing emergency application systems is realized. In the to-be concept the findings were summarized and possible architectural sketches for future emergency applications were given. Furthermore, one conclusion of dealing with this topic is that a design alone is not sufficient to guarantee a good working app. That is why the requirements for the thesis were expanded by the connection to and integration of rescue centers in the architecture of the emergency app.
At the end of the thesis, the reader will receive a comprehensive overview of the provision of emergency data to the rescue control centers by different transmission channels. Furthermore, conditions for the system requirements are also presented as possible scenarios of the architecture of the whole system of the emergency application. The generic and modular approach guarantees that the system is open for future development and integration of functions of other applications.
Im Rahmen dieser Masterarbeit wird ein umfassender Überblick über die Vielfalt der Sicherheitsmodelle gegeben, indem ausgewählte Sicherheitsmodelle beschrieben, klassifiziert und miteinander verglichen werden.
Sicherheitsmodelle beschreiben in einer abstrakten Weise die sicherheitsrelevanten
Komponenten und Zusammenhänge eines Systems. Mit den Sicherheitsmodellen können komplexe Sachverhalte veranschaulicht und analysiert werden.
Da Sicherheitsmodelle unterschiedliche Sicherheitsaspekte behandeln, beschäftigt
sich diese Arbeit mit der Ausarbeitung eines Klassifizierungsschemas, welches
die strukturelle und konzeptuelle Besonderheiten der Modelle in Bezug auf die zugrundeliegenden Sicherheitsaspekte beschreibt. Im Rahmen des Klassifizierungsschemas werden die drei grundlegenden Modellklassen gebildet: Zugriffskontrollmodelle, Informationsflussmodelle und Transaktionsmodelle.
Sicherheitsmodelle werden in einem direkten und indirekten Vergleich gegenüber gestellt. Im letzten Fall werden sie einer oder mehrerer Modellklassen des Klassifizierungsschemas zugeordnet. Diese Klassifizierung erlaubt, Aussagen über die betrachteten Sicherheitsaspekte und die strukturellen bzw. konzeptuellen Besonderheiten eines Sicherheitsmodells in Bezug auf die anderen Sicherheitsmodelle
zu machen.
Beim direkten Vergleich werden anhand der ausgewählten Kriterien die Eigenschaften
und Aspekte der Sicherheitsmodelle orthogonal zu den Modellklassen
betrachtet.
Human detection is a key element for human-robot interaction. More and more robots are used in human environments, and are expected to react to the behavior of people. Before a robot can interact with a person, it must be able to detect it at first. This thesis presents a system for the detection of humans and their hands using a RGB-D camera. First, a model based hypotheses for possible positions of humans are created to recognize a person. By using the upper parts of the body are used to extract, new features based on relief and width of a person- head and shoulders are extracted. The hypotheses are checked by classifying the features with a support vector machine (SVM). The system is able to detect people in different poses. Both sitting and standing humans are found, by using the visible upper parts of the person. Moreover, the system is able to recognize if a human is facing or averting the sensor. If the human is facing the sensor, the color information and the distance between hand and body are used to detect the positions of the person- hands. This information is useful for gestures recognition and thus can further enhances human-robot interaction.
Iterative Signing of RDF(S) Graphs, Named Graphs, and OWL Graphs: Formalization and Application
(2013)
When publishing graph data on the web such as vocabulariesrnusing RDF(S) or OWL, one has only limited means to verify the authenticity and integrity of the graph data. Today's approaches require a high signature overhead and do not allow for an iterative signing of graph data. This paper presents a formally defined framework for signing arbitrary graph data provided in RDF(S), Named Graphs, or OWL. Our framework supports signing graph data at different levels of granularity: minimum self-contained graphs (MSG), sets of MSGs, and entire graphs. It supports for an iterative signing of graph data, e. g., when different parties provide different parts of a common graph, and allows for signing multiple graphs. Both can be done with a constant, low overhead for the signature graph, even when iteratively signing graph data.
Autonomous systems such as robots already are part of our daily life. In contrast to these machines, humans an react appropriately to their counterparts. People can hear and interpret human speech, and interpret facial expressions of other people.
This thesis presents a system for automatic facial expression recognition with emotion mapping. The system is image-based and employs feature-based feature extraction. This thesis analyzes the common steps of an emotion recognition system and presents state-of-the-art methods. The approach presented is based on 2D features. These features are detected in the face. No neutral face is needed as reference. The system extracts two types of facial parameters. The first type consists of distances between the feature points. The second type comprises angles between lines connecting the feature points. Both types of parameters are implemented and tested. The parameters which provide the best results for expression recognition are used to compare the system with state-of-the-art approaches. A multiclass Support Vector Machine classifies the parameters.
The results are codes of Action Units of the Facial Action Coding System. These codes are mapped to a facial emotion. This thesis addresses the six basic emotions (happy, surprised, sad, fearful, angry, and disgusted) plus the neutral facial expression. The system presented is implemented in C++ and is provided with an interface to the Robot Operating System (ROS).
The goal of this Bachelor thesis was programming an existig six-legged robot, which should be able to explore any environment and create a map of it autonomous. A laser scanner is to be integrated for cognition of this environment. To build the map and locate the robot a suitable SLAM(Simultaneous Localization and Mapping) technique will be connected to the sensor data. The map is reported to be the robots base of path planning and obstancle avoiding, what will be developed in the scope of the bachelor thesis, too. Therefore both GMapping and Hector SLAM will be implemented and tested.
An exploration algorithm is described in this bachelor thesis for exploring the robots environment. The implementation on the robot takes place in the space of ROS(Robot Operating System) framework on a "Raspberry Pi" miniature PC.
A Kinect device has the ability to record color and depth images simultaneously. This thesis is an attempt to use the depth image to manipulate lighting information and material properties in the color image. The presented method of lighting and material manipulation needs a light simulation of the lighting conditions at the time of recording the image. It is used to transform information from a new light simulation directly back into the color image. Since the simulations are performed on a three-dimensional model, a way is searched to generate a model out of single depth image. At the same time the text will react to the problems of the depth data acquisition of the Kinect sensor. An editor is designed to make lighting and material manipulations possible. To generate a light simulation, some simple, real-time capable rendering methods and lighting modells are proposed. They are used to insert new illumination, shadows and reflections into the scene. Simple environments with well defined lighting conditions are manipulated in experiments to show boundaries and possibilities of the device and the techniques being used.
This thesis describes the conception, implementation and evaluation of a collaborative multiplayer game for preschoolers for mobile devices.
The main object of this thesis is to find out, if mobile devices like smartphones and tablet computers are suitable for the interaction of children. In order to develop this kind of game relevant aspects were researched. On this basis a game was designed which was finally tested by preschoolers.
From September 4 to 11, 1992, a fiirst meeting between Ukrainian and German scientists interested in mathematical and computer modeling of social processes was held at Vorzel' near Kiev. The meeting had been planned for nearly three years by Igor V. Chernenko and Mikhail V. Kuz'min, then members of the research group on mathematical modeling in sociology at the Institute of Sociology of the Academy of Science of the Ukrainian Republic, and had to be postponed twice due to the political development in the former Soviet Union, but thanks to the organizers' perseverance (and in spite of a strike of the airport personell at Kiev Borispol Airport on the eve of the conference) the conference could at last be realized.rnThe main purpose of the conference was to discuss a synergetic interpretation of large-scale destructive social processes as catastrophic phenomena in self-organized systems.
This paper originates from the FP6 project "Emergence in the Loop (EMIL)" which explores the emergence of norms in artificial societies. Part of work package 3 of this project is a simulator that allows for simulation experiments in different scenarios, one of which is collaborative writing. The agents in this still prototypical implementation are able to perform certain actions, such as writing short texts, submitting them to a central collection of texts (the "encyclopaedia") or adding their texts to texts formerly prepared by other agents. At the same time they are able to comment upon others' texts, for instance checking for correct spelling, for double entries in the encyclopaedia or for plagiarisms. Findings of this kind lead to reproaching the original authors of blamable texts. Under certain conditions blamable activities are no longer performed after some time.
Customization is a phenomenon which was introduced quite early in information systems literature. As the need for customized information technology is rising, different types of customization have emerged. In this study, customization processes in information systems are analyzed from a perspective based on the concept of open innovation. The objective is to identify how customization of information systems can be performed in an open innovation context. The concept of open innovation distinguishes three processes: Outside-in process, inside-out process and coupled process. After categorizing the selected journals into three core processes, the findings of this analysis indicated that there is a major concentration on outside-in processes. Further research on customization in coupled and inside-out processes is recommended. In addition, the establishment of an extensive up-to-date definition of customization in information systems is suggested.
This paper consists of the observation of existing first aid applications for smartphones and comparing them to a first aid application developed by the University of Koblenz called "Defi Now!". The main focus lies on examining "Defi Now!" in respect to its usability based on the dialogue principles referring to the seven software ergonomic principles due to the ISO 9241-110 standard. These are known as suitability for learning, controllability, error tolerance, self-descriptiveness, conformity with user expectations, suitability for the task, and suitability for individualization.
Therefore a usability study was conducted with 74 participants. A questionnaire was developed, which was to be filled out by the test participants anonymously. The test results were used for an optimization of the app referring its' usability.
Various best practices and principles guide an ontology engineer when modeling Linked Data. The choice of appropriate vocabularies is one essential aspect in the guidelines, as it leads to better interpretation, querying, and consumption of the data by Linked Data applications and users.
In this paper, we present the various types of support features for an ontology engineer to model a Linked Data dataset, discuss existing tools and services with respect to these support features, and propose LOVER: a novel approach to support the ontology engineer in modeling a Linked Data dataset. We demonstrate that none of the existing tools and services incorporate all types of supporting features and illustrate the concept of LOVER, which supports the engineer by recommending appropriate classes and properties from existing and actively used vocabularies. Hereby, the recommendations are made on the basis of an iterative multimodal search. LOVER uses different, orthogonal information sources for finding terms, e.g. based on a best string match or schema information on other datasets published in the Linked Open Data cloud. We describe LOVER's recommendation mechanism in general and illustrate it alongrna real-life example from the social sciences domain.