004 Datenverarbeitung; Informatik
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Replikation einer Multi-Agenten-Simulationsumgebung zur Überprüfung auf Integrität und Konsistenz
(2012)
In dieser Master -Arbeit möchte ich zunächst eine Simulation vorstellen, mit der das Verhalten von Agenten untersucht wird, die in einer generierten Welt versuchen zu über leben und dazu einige Handlungsmöglichkeiten zur Auswahl haben. Anschließend werde ich kurz die theoretischen Aspekte beleuchten, welche hier zu Grunde liegen. Der Hauptteil meiner Arbeit ist meine Replikation einer Simulation, die von Andreas König im Jahr 2000 in Java angefertigt worden ist [Kö2000] . Ich werde hier seine Arbeit in stark verkürzter Form darstellen und anschließend auf meine eigene Entwicklung eingehen.
Im Schlussteil der Arbeit werde ich die Ergebnisse meiner Simulation mit denen von Andreas König vergleichen und die verwendeten Werkzeuge (Java und NetLogo) besprechen. Zum Abschluss werde ich in einem Fazit mein Vorhaben kurz zusammenfassen und berichten was sich umsetzen ließ, was nicht funktioniert hat und warum.
Standards are widely-used in the computer science and IT industry. Different organizations like the International Organization for Standardization (SO) are involved in the development of computer related standards. An important domain of standardization is the specification of data formats enabling the exchange of information between different applications. Such formats can be expressed in a variety of schema languages thereby defining sets of conformant documents. Often the use of multiple schema languages is required due to their varying expressive power and different kind of validation requirements.rnThis also holds for the Specification Common Cartridge which is maintained by the IMS Global Learning Consortium. The specification defines valid zip packages that can be used to aggregate different learning objects. These learning objects are represented by a set of files which are a part of the package and can be imported into a learning management system. The specification makes use of other specifications to constrain the contents of valid documents. Such documents are expressed in the eXtensible Markup Language and may contain references to other files also part of the package. The specification itself is a so-called domain profile. A domain profile allows the modification of one or more specifications to meet the needs of a particular community. Test rules can be used to determine a set of tasks in order to validate a concrete package. The execution is done by a testsystem which, as we will show, can be created automatically. Hence this method may apply to other package based data formats that are defined as a part of a specification.
This work will examine the applicability of this generic test method to the data formats that are introduced by the so called Virtual Company Dossier. These formats are used in processes related to public e-procurement. They allow the packaging of evidences that are needed to prove the fulfillment of criteria related to a public tender. The work first examines the requirements that are common to both specifications. This will introduce a new view on the requirements by introducing a higher level of abstraction. The identified requirements will then be used to create different domain profiles each capturing the requirements of a package based data format. The process is normally guided by supporting tools that ease the capturing of a domain profile and the creation of testsystems. These tools will be adapted to support the new requirements. Furtheron the generic testsystem will be modified. This system is used as a basis when a concrete testsystem is created.
Finally the author comes to a positive conclusion. Common requirements have been identified and captured. The involved systems have been adapted allowing the capturing of further types of requirements that have not been supported before. Furthermore the background of the specifications quite differ. This indicates that the use of domain profiles and generic test technologies may be suitable in a wide variety of other contexts.
Planning routes for trucks with a trailer is a complex procedure. In order to simplify this process, a route is segmented into elementary components, which represents basic motions of the considered vehicle. These elementary components are called maneuvers and are composed of two party. First, paths are constructed for certain reference points. Second, the vehicle is enclosed by a corridor during the execution of a maneuver. The paths of the vehicle have to take driveability into consideration. They must respect the kinematic constraints of the vehicle. The maneuver corridor can be used as a basis to guarantee collision-free motion planing. No part of the vehicle leaves the corridor during the maneuver. There are different types of maneuvers. Currently, the bending maneuver, the cusp maneuver and the straight line maneuver can be distinguished. In addition, a maneuver can be created with two different construction methods, the conventional and the iterative method.
In this thesis, a data structure to construct a maneuver is designed and implemented. The data structure is integrated into an already existing tool. The user can interact with the software to adjust various parameters of a maneuver. Afterwards the maneuver is generated based on these parameters. This also includes a visualization within the software, which can plot the parts of a maneuver. The visualization can be exported to an image file.
Web-programming is a huge field of different technologies and concepts. Each technology implements a web-application requirement like content generation or client-server communication. Different technologies within one application are organized by concepts, for example architectural patterns. The thesis describes an approach for creating a taxonomy about these web-programming components using the free encyclopaedia Wikipedia. Our 101companies project uses implementations to identify and classify the different technology sets and concepts behind a web-application framework. These classifications can be used to create taxonomies and ontologies within the project. The thesis also describes, how we priorize useful web-application frameworks with the help of Wikipedia. Finally, the created implementations concerning web-programming are documented.
To meet the growing demands in the automotive industry, car manufacturers constantly reduce the depth of production and shift value-adding processes to the suppliers. This requires that companies work together more closely and promotes the creation of complex logistics networks. To meet the requirements for information exchange, a consortium of automobile manufacturers launched the project RFID-based Automotive Network (RAN) in 2009. The initiative aims at creating a standardized architecture for efficient material flow management along the entire supply chain. Core component of this architecture is the Informationbroker, an information unit which automatically communicates data which is captured via Auto-ID technology to supply chain participants. The thesis focuses in cooperation with the IBS AG, a software company and consortium partner in the project, on the exchange of goods data.
At first, theoretical foundations are presented by describing the characteristics of a supply chain and explaining standardization efforts and related processes. The chapter on the supply chain focuses on trends in the automotive industry to create a link to the project. The topic of standardization provides in-depth information on electronic data exchange standards in order to additionally create a transition to the Informationbroker concept. In the analytical part, reference projects will be presented with a similar problem and set in relation to RAN. According to project documents, system requirements will be defined and models will be created in order to illustrate the problem. Rich Pictures are used to describe the basis and target state.
Based on these models, the flow of goods related data is depicted between two companies and the role of the Informationbroker for the information exchange is clarified. The thesis aims at establishing an understanding of the challenges of the project and how the proposed concepts of the initiative can lead to an optimization of an automotive supply chain.
The estimation of various social objects is necessary in different fields of social life, science, education, etc. This estimation is usually used for forecasting, for evaluating of different properties and for other goals in complex man-machine systems. At present this estimation is possible by means of computer and mathematical simulation methods which is connected with significant difficulties, such as: - time-distributed process of receiving information about the object; - determination of a corresponding mathematical device and structure identification of the mathematical model; - approximation of the mathematical model to real data, generalization and parametric identification of the mathematical model; - identification of the structure of the links of the real social object. The solution of these problems is impossible without a special intellectual information system which combines different processes and allows predicting the behaviour of such an object. However, most existing information systems lead to the solution of only one special problem. From this point of view the development of a more general technology of designing such systems is very important. The technology of intellectual information system development for estimation and forecasting the professional ability of respondents in the sphere of education can be a concrete example of such a technology. Job orientation is necessary and topical in present economic conditions. It helps tornsolve the problem of expediency of investments to a certain sphere of education. Scientifically validated combined diagnostic methods of job orientation are necessary to carry out professional selection in higher education establishments. The requirements of a modern society are growing, with the earlier developed techniques being unable to correspond to them sufficiently. All these techniques lack an opportunity to account all necessary professional and personal characteristics. Therefore, it is necessary to use a system of various tests. Thus, the development of new methods of job orientation for entrants is necessary. The information model of the process of job orientation is necessary for this purpose. Therefore, it would be desirable to have an information system capable of giving recommendations concerning the choice of a trade on the basis of complex personal characteristics of entrants.
Innovation can help a forward-looking company to rise up very quickly, furthermore, innovative products and services bring a company to a stage where it can win new segments of customers and be ahead of the competition. For their innovation process, the companies can distinguish between open and closed innovation. In this case, we will focus on open innovation and how companies share their innovation processes for the benefit of the company. They use information and innovation systems to define their innovation process, as well as, track innovative ideas and the phase of their development. There are always pros and cons when it comes to open innovation processes in an organization. We will try to look at certain examples in the business world to illustrate how good or bad an open innovation process can be for a company. In this Bachelor thesis, we will try to point out the essential criteria for an open innovation process and illustrate companies which have used open innovation processes. In some cases it went successfully and for some companies it went unsuccessfully.
In this work, some network protocols with Wireshark Protokollanalyser should be observed and described the deal with them. Wireshark is an offshoot of "Ethereal", one of the most popular protocol analyzer. Wireshark analysis network traffic, draws on it and make it clear . For the simulation of the network is used VNUML. Since VNUML can only be used under Linux, andLinux is running as a virtual machine in between to work in Windows to be able to.
In diesem Bericht wird der Einsatz von drahtlosen Sensornetzen zur Temperaturmessung in Fließgewässern untersucht. Es wird dargestellt, inwieweit solche Netze als Bindeglied zwischen Fernerkundung und stationären Sensoren eingesetzt werden können. Es werden die Anforderungen an Sensornetze für die Anwendung Gewässermonitoring ermittelt und eine prototypische Realisierung von Netzknoten für ein solches Sensornetz dargestellt. Als Ergebnis dieser Arbeit werden die Genauigkeit von Temperaturmessungen mit solchen Sensorknoten im Vergleich zu einem Temperaturlogger als Referenzsystem dargestellt. Die Messungen zeigen, dass eine vergleichsweise gute Messgenauigkeit zu geringen Kosten erreichbar ist. Durch Weiterentwicklung des hier dargestellten Prototypen steht für die Temperaturüberwachung in Gewässern ein vielversprechendes und kostengünstiges neues Messinstrument zur Verfügung. Dieses kann auf der einen Seite in tieferen Regionen Gewässertemperaturen messen, als dies mit Fernerkundung möglich ist, und auf der anderen Seite eine höhere räumliche Auflösung als stationäre Messstationen erreichen. Zusätzlich dienen die Literaturrecherche und die Formulierung der Kriterien einer Eingrenzung des Anwendungsbereichs für weiterführende Arbeiten.
Analyse TV-basierter Interaktion für Senioren: Umsetzung und Evaluation im Gesundheitsbereich
(2007)
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.
In the last years the e-government concentrated on the administrative aspects of administrative modernisation. In the next step the e-discourses will gain in importance as an instrument of the public-friendliness and means of the e-democracy/e-participation. With growing acceptance of such e-discourses, these will fastly reach a complexity, which could not be mastered no more by the participants. Many impressions, which could be won from presence discussions, will be lacking now. Therefore the exposed thesis has the objective of the conception and the prototypical implementation of an instrument (discourse meter), by which the participants, in particular the moderators of the e-discourse, are capable to overlook the e-discourse at any time and by means of it, attain their discourse awareness. Discourse awareness of the present informs about the current action in the e-discourse and discourse awareness of the past about the past action, by which any trends become visible. The focus of the discourse awareness is located in the quantitative view of the action in the e-discourse. From the model of e-discourse, which is developed in this thesis, the questions of discourse awareness are resulting, whose concretion is the basis for the implementation of the discourse meter. The discourse sensors attached to the model of the e-discourse are recording the actions of the e-discourse, showing events of discourse, which are represented by the discourse meter in various forms of visualizations. The concept of discourse meter offers the possibility of discourse awareness relating to the present as monitoring and the discourse awareness relating to the past as query (quantitative analysis) to the moderators of the e-discourse.
Einer der Forschungsschwerpunkte der AG Rechnernetze ist das Routing Information Protocol. Eine eigene kompatible Erweiterung dieses Routingprotokolls ist der Routing Information Protocol with Metric-based Topology Investigation (RMTI [ehemals RIP-MTI]). Um dieses Protokoll testen und mit seinem Vorgänger vergleichen zu können, wird die Virtualisierungssoftware VNUML eingesetzt. In diesen virtualisierten Netzwerken werden Router, die das RMTI-Protokoll einsetzten, mittels der Zebra/Quagga Routing Software Suite beobachtet. Dabei wird das Verhalten des Protokolls in unterschiedlichsten Simulationssituationen analysiert und bewertet. Um solche Testabläufe zentral zu steuern und protokollieren zu können wurde die Anwendung RIP-XT (XTPeer) erstellt und in fortführenden Diplomarbeiten kontinuierlich erweitert. Sie ist Schnittstelle zu den Zebra/Quagga-Routern und kann diese steuern. Zusätzlich sammelt und analysiert sie die Routing-Informationen der Router.Über ein GUI kann ein Benutzer diese Abläufe steuern. Um einen visuellen Überblick über eine Netzwerktopologie zu erhalten, besitzt das GUI auch eine Topologie-Anzeige. Die Anzeige repräsentiert das Gesamte Netzwerk durch Symbole, über die auch Interaktionen mit der Simulation möglich sind. Ziel dieser Diplomarbeit war es, die bisherige Topologie-Anzeige zu überarbeiten, um sie für neue Anforderungen anzupassen. Des weiteren wurden funktionale Erweiterungen in das GUI des RIP-XTs eingebettet.
This thesis addresses the automated identification and localization of a time-varying number of objects in a stream of sensor data. The problem is challenging due to its combinatorial nature: If the number of objects is unknown, the number of possible object trajectories grows exponentially with the number of observations. Random finite sets are a relatively new theory that has been developed to derive at principled and efficient approximations. It is based around set-valued random variables that contain an unknown number of elements which appear in arbitrary order and are themselves random. While extensively studied in theory, random finite sets have not yet become a leading paradigm in practical computer vision and robotics applications. This thesis explores random finite sets in visual tracking applications. The first method developed in this thesis combines set-valued recursive filtering with global optimization. The problem is approached in a min-cost flow network formulation, which has become a standard inference framework for multiple object tracking due to its efficiency and optimality. A main limitation of this formulation is a restriction to unary and pairwise cost terms. This circumstance makes integration of higher-order motion models challenging. The method developed in this thesis approaches this limitation by application of a Probability Hypothesis Density filter. The Probability Hypothesis Density filter was the first practically implemented state estimator based on random finite sets. It circumvents the combinatorial nature of data association itself by propagation of an object density measure that can be computed efficiently, without maintaining explicit trajectory hypotheses. In this work, the filter recursion is used to augment measurements with an additional hidden kinematic state to be used for construction of more informed flow network cost terms, e.g., based on linear motion models. The method is evaluated on public benchmarks where a considerate improvement is achieved compared to network flow formulations that are based on static features alone, such as distance between detections and appearance similarity. A second part of this thesis focuses on the related task of detecting and tracking a single robot operator in crowded environments. Different from the conventional multiple object tracking scenario, the tracked individual can leave the scene and later reappear after a longer period of absence. Therefore, a re-identification component is required that picks up the track on reentrance. Based on random finite sets, the Bernoulli filter is an optimal Bayes filter that provides a natural representation for this type of problem. In this work, it is shown how the Bernoulli filter can be combined with a Probability Hypothesis Density filter to track operator and non-operators simultaneously. The method is evaluated on a publicly available multiple object tracking dataset as well as on custom sequences that are specific to the targeted application. Experiments show reliable tracking in crowded scenes and robust re-identification after long term occlusion. Finally, a third part of this thesis focuses on appearance modeling as an essential aspect of any method that is applied to visual object tracking scenarios. Therefore, a feature representation that is robust to pose variations and changing lighting conditions is learned offline, before the actual tracking application. This thesis proposes a joint classification and metric learning objective where a deep convolutional neural network is trained to identify the individuals in the training set. At test time, the final classification layer can be stripped from the network and appearance similarity can be queried using cosine distance in representation space. This framework represents an alternative to direct metric learning objectives that have required sophisticated pair or triplet sampling strategies in the past. The method is evaluated on two large scale person re-identification datasets where competitive results are achieved overall. In particular, the proposed method better generalizes to the test set compared to a network trained with the well-established triplet loss.
MP3 Player for Nintendo DS
(2007)
Ziel der Arbeit ist es, einen MP3-Player zu entwickeln, der eine Benutzerinteraktion ermöglicht, wie es gängige Computerprogramme zur Wiedergabe von Musik tun. Der Benutzer soll über eine grafische Oberfläche MP3-Dateien laden, abspielen und in Playlisten organisieren können. Ferner soll es möglich sein, Metadaten wie Titel, Autor, Genre, Veröffentlichungsjahr und vieles weitere als zusätzlichen Tag zu speichern und zu editieren. Diese Informationen soll die Software auch beim Abspielen eines Musikstückes auslesen und dem Nutzer übersichtlich anzeigen. Hier scheitern die meisten Player aufgrund ihres kleinen Displays. Außerdem soll der MP3-Player auch rudimentäre Funktionen zur Echtzeitmanipulation der Musikwiedergabe bieten. Als Hardware zum Abspielen der Musikdateien dient die Spielekonsole Nintendo DS, welche aufgrund ihrer beiden Displays genügend Anzeigemöglichkeiten für eine grafische Benutzerführung bietet. Eines der beiden Displays dient zudem als Touchscreen und kann für Eingaben verwendet werden.
The automatic detection of position and orientation of subsea cables and pipelines in camera images enables underwater vehicles to make autonomous inspections. Plants like algae growing on top and nearby cables and pipelines however complicate their visual detection: the determination of the position via border detection followed by line extraction often fails. Probabilistic approaches are here superior to deterministic approaches. Through modeling probabilities it is possible to make assumptions on the state of the system even if the number of extracted features is small. This work introduces a new tracking system for cable/pipeline following in image sequences which is based on particle filters. Extensive experiments on realistic underwater videos show robustness and performance of this approach and demonstrate advantages over previous works.
Autonomous exhaustive exploration of unknown indoor environments with the mobile robot "Robbie"
(2007)
Rettungsroboter helfen nach Katastrophen wie z.B. Erdbeben dabei, in zerstörten Gebäuden Überlebende zu finden. Die Aufgabe, die Umgebung effizient möglichst vollständig abzusuchen und dabei eine Karte zu erstellen, die den Rettungskräften bei der Bergung der Opfer zur Orientierung dient, soll der Roboter autonom erfüllen. Hierzu wird eine Explorationsstrategie benötigt; eine Strategie zur Navigation in bekanntem und zur Erkundung von unbekanntem Gelände. Für den mobilen Roboter "Robbie" der Arbeitsgruppe Aktives Sehen wurde in dieser Arbeit ein Grenzen-basierter Ansatz zur Lösung des Explorationsproblems ausgewählt und implementiert. Hierzu werden Grenzen zu unbekanntem Gelände aus der Karte, die der Roboter erstellt, extrahiert und angefahren. Grundlage der Navigation zu einem so gefundenen Wegpunkt bildet die sog. Pfad-Transformation (Path-Transform).
Wie bereitet man komplizierte, technische Sachverhalte einfach und verständlich auf, damit sie auch der normalen Benutzer ohne tiefergehendes technisches Hintergrundwissen schnell und ohne lange Einarbeitungszeit und langwierige Erklärungen zu nutzen weiß? In dieser Studenarbeit geht es um genau diese Frage - Nichtinformatikern die Vorzüge und die Arbeit mit semantischen (Such)anfragen zu erleichtern, wenn nicht sogar überhaupt erst zu ermöglichen, sowie die Neuentwicklung und SPARQL-Erweiterung Networked Graphs von Simon Schenk innerhalb der AG Staab/Universität Koblenz zu präsentieren.
Social media platforms such as Twitter or Reddit allow users almost unrestricted access to publish their opinions on recent events or discuss trending topics. While the majority of users approach these platforms innocently, some groups have set their mind on spreading misinformation and influencing or manipulating public opinion. These groups disguise as native users from various countries to spread frequently manufactured articles, strong polarizing opinions in the political spectrum and possibly become providers of hate-speech or extremely political positions. This thesis aims to implement an AutoML pipeline for identifying second language speakers from English social media texts. We investigate style differences of text in different topics and across the platforms Reddit and Twitter, and analyse linguistic features. We employ feature-based models with datasets from Reddit, which include mostly English conversation from European users, and Twitter, which was newly created by collecting English tweets from selected trending topics in different countries. The pipeline classifies language family, native language and origin (Native or non-Native English speakers) of a given textual input. We evaluate the resulting classifications by comparing prediction accuracy, precision and F1 scores of our classification pipeline to traditional machine learning processes. Lastly, we compare the results from each dataset and find differences in language use for topics and platforms. We obtained high prediction accuracy for all categories on the Twitter dataset and observed high variance in features such as average text length especially for Balto-Slavic countries.
As Enterprise 2.0 (E2.0) initiatives are gradually moving out of the early experimentation phase it is time to focus greater attention on examining the structures, processes and operations surrounding E2.0 projects. In this paper we present the findings of an empirical study to investigate and understand the reasons for initiating E2.0 projects and the benefits being derived from them. Our study comprises seven in-depth case studies of E2.0 implementations. We develop a classification and means of visualising the scope of E2.0 initiatives and use these methods to analyse and compare projects.
Our findings indicate a wide range of motivations and combinations of technology in use and show a strong emphasis towards the content management functionality of E2.0 technologies.
Im Vergleich zu herkömmlicher Computergrafik (perspektivische Projektion) bietet Raytracing entscheidende Vorteile, die hauptsächlich in der vergleichsweise hohen physikalischen Korrektheit der Methode begründet sind. Die Schwächen liegen hingegen im immensen Rechenaufwand.
Ein Raytracer ist vergleichsweise so rechenintensiv, weil für jeden Pixel mindestens ein Strahl verschickt werden muss. Dieser muss gegen alle Objekte im Raum geschnitten werden. Hinzu kommen noch die Strahlen, die entstehen, wenn Strahlen an Objekten reflektiert werden (Rekursion). Um diesen Rechenaufwand zu verkleinern und zusätzlich ein besseres Bild zu erzeugen, soll der adaptive Sampler den Raytracer unterstützen. Der adaptive Sampler soll während des Rendervorgangs den progressiven Fortschritt in der Bildgenerierung beobachten und Pixel von der weiteren Berechnung ausschließen, für die sich ein zusätzliches Verschießen von Strahlen nicht mehr lohnt.
Anders als der rein progressive Raytracer hört der adaptive Sampler mit dem Konvergieren des Bildes auf zu rechnen. Der adaptive Sampler soll so dafür sorgen, dass schneller ein besseres Bild erzeugt wird und somit die Performanz gesteigert wird. Insgesamt erwartet man sich vom adaptiven Sampler Vorteile bei der Berechnung von bestimmten Szenen. Unter anderem eine Verbesserung bei Szenen mit rein diffus beleuchteten Bildbereichen, sowie eine Verbesserung bei Szenen mit unterschiedlich rechenintensiven Bildbereichen. Ein normaler Raytracer kann nicht beurteilen, wie sinnvoll seine Schüsse sind. Er kann nur mehr Strahlen verschießen, in der Hoffnung, das Bild damit effektiv zu verbessern.
Es gibt jedoch viele Szenarien, bei denen eine linear steigende Schussanzahl pro Pixel keine gleichmäßige Verbesserung im Bild erzeugt. Das bedeutet, dass Bereiche im Bild schon gut aussehen, während andere noch sehr verrauscht sind. Man möchte nun Bildbereiche, die bereits konvergiert sind, in denen sich ein weiterer Beschuss also nicht mehr bemerkbar macht, ausschließen und die Rechenleistung dort nutzen, wo man sie noch braucht.
Wichtig dabei ist, dass Pixel nicht ungewollt zu früh von der Berechnung ausgeschlossen werden, die nicht weit genug konvergiert sind. Der adaptive Sampler soll so lange arbeiten, bis jeder Pixel dauerhaft keine Änderungen mehr vorweist. Das bedeutet, dass die Wahrscheinlichkeit für eine signifikante Farbänderung eines Pixels durch Verschießen eines Strahls (bei mehreren Lichtquellen in RenderGin mehrere Strahlen pro Pixel) klein genug ist. Es wird zwar intern keine Wahrscheinlichkeit berechnet, jedoch bekommt der Raytracer eine Art Gedächtnis: Er speichert die Veränderungen im beleuchteten Bild und deren Verlauf in eigenen Gedächtnisbildern. Das "Gedächtnis" für das alte Bild (Zustand des Bildes in der letzten Iteration über die Pixel) repräsentiert dabei das Kurzzeitgedächtnis. Es ist absolut genau. Das Langzeitgedächtnis wird von drei verschiedenen Bildern repräsentiert. Das erste gibt die Anzahl der verschossenen Strahlen pro Pixel an. Das zweite ist ein Wahrheitswertebild, das für jeden Pixel angibt, ob dieser noch in die Berechnung einbezogen werden soll. Das dritte Bild gibt an, wie oft jeder Pixel eine Farbänderung vollzogen hat, die geringer ist als der geforderte Maximalabstand eines Pixels zu sich selbst (vor und nach dem Verschießen eines weiteren Strahls).
Mit diesen drei Bildern ist es möglich, zusätzliche quantitative Informationen zu den qualitativen Informationen des Vergleichs vom neuen und alten Bild zu berücksichtigen.
In dieser Arbeit kläre ich die Frage, ob die gewünschten Effekte eintreten und ob bei Integration in die bestehende Struktur von RenderGin ein Performanzgewinn möglich ist. Die Umsetzung eines adaptiven Samplers ist als Plug-In in der Software RenderGin von Numenus GmbH geschehen. RenderGin ist ein echtzeitfähiger, progressiver Raytracer, der sich durch seine Performanz auszeichnet. Die Bildgenerierung geschieht allein auf der CPU, die Grafikkarte wird lediglich zur Anzeige des erzeugten Bildes benötigt.
Die Umsetzung und Programmierung des Plug-Ins ist in Microsoft Visual Studio 2010 geschehen unter Verwendung des RenderGin SDK der Numenus GmbH.
In this work has been examined, how the existing model of the simulation of cables and hoses can be advanced. Therefore an investigation has been made on the main influences to the shape simulation and the factors of constraints and side conditions were analyzed. For the validation of the accuracy, the simulation has to be compared to real specimen behavior. To obtain a very precise digitalization of the shape, the choice was made to use a laser scanner that converts the pointcloud into a .vrml file which can be imported into the simulation environment. The assumption was that the simulation method itself has the highest impact to the simulated shape. This is why the capabilities of the most sophisticated methods have been analyzed. The main criterion for the success of a simulation approach proved not to be accuracy, as expected. Process integration and usability showed to be of higher interest for the efficient exertion. Other factors like the pricing, the functionality and the real-time capability were assayed as well. The analyzed methods are based on the solution of the equations of elasticity with different ways of discetization, finite-elements and a spring-impulse-system. Since the finite-element-system takes several minutes for the computation of the shape and the spring-impulse-system reacts retarded on user manipulation, the competitiveness of these approaches is low. The other methods distinguish more in real-time performance, data interfaces and functionality than in accuracy. For the accuracy of a system, the consideration of other factors proved to be very important. As one of these main factors, the accurate assignment of the material properties was indicated. Until the start of this work, only the finite-element-approach dealt with this factor, but no documentation or validation is provided. In the publications of the other methods, the material properties are estimated to obtain a plausible simulation shape. Therefore the specific material values of real specimen have been measured and assigned to the simulation. With the comparison to the real shape it has been proven that the accuracy is very high with the measured properties. Since these measurements are very costly and time consuming, an investigation on a faster and cheaper way to obtain these values has been made. It has been assumed that with the knowledge of the cross-section it should be possible to compute the specimen behavior. Since the braid distribution changes individually from specimen to specimen, a more general way to obtain the values needed to be found. The program composer has been developed, where only the number of the different braids and the taping is entered. It computes with very high precision the stiffness, the density and the final diameter of the bundle. With the measured values and the fitting to the real shape it has been proven that the simulation approach reflects the precise behavior of cables and hoses. Since the stiffness of the single braids is wasteful to measure, a measurement setup was created where the stiffness has a large impact to the shape. With known density, the stiffness of the specimen can be reconstructed precisely. Thus a fast and beneficial way of obtaining the stiffness of a cable has been invented. The poissons ratio of cables and bundles cannot be measured with a tensile test, since the inner structure is very complex. For hoses, the variation of the inner diameter has been measured during the tensile test as well. The resulting values were reasonable, but their accuracy could not be proven. For cables and hoses, it has been tried to obtain the poissons ratio via the computation of the cross section, but the influence of individual changes and the crosstalk of the braids is very high. Therefore a setup was constructed where the torsion stiffness can be measured. For cables and hoses, the individual cross-sections and taping lead to varying results. For hoses, expected and repeatable good values for the poissons ratio were obtained. The low influence of the poisons ratio in the range between 0 and 0.5 has been proven. Therefore we decided to follow the advice of [Old06] and our own experiences to set the poisons ratio for cables and bundles to 0.25. With the knowledge of the measurability and the capabilities of the developed program composer, a procedure to obtain material properties for bundles has been designed. 1. Measurement of the braid density with via pyknometer or mass, length and diameter. 2. Empirical reconstruction of the stiffness with the designed setup. 3. Composing the bundle with the program composer. 4. Adding a factor for the taping and transfer the values to the simulation. The model of the cable simulation has been improved as follows: The main influences in the simulation of cables and hoses are the simulation method, the material properties and the geometric constraints. To obtain higher accuracy, an investigation on the correct material properties is indispensable. The scientific determination of material properties for the simulation of cables, bundles and hoses has been performed for the first time. The influence of geometrical constraints has been analyzed and documented. The next steps are the analysis of pre-deformation and further investigations to the determination of the poisons ratio with a more precise torsion test. All analysis were made with the simulation approach fleXengine. A comparison to other simulation methods would be of high interest.
Performanz von RIP-MTIfi
(2009)
Diese Diplomarbeit beschäftigt sich mit der Performanz von RIP-MTI, insbesondere mit der Performanz der Schleifenerkennung. Ziel der Arbeit ist es, die Zeitdauer der Schleifenerkennung von RIP-MTI zu untersuchen und Probleme, welche bei der Erkennung von Schleifen auftreten könen, aufzudecken und zu lösen.
Generalized methods for automated theorem proving can be used to compute formula transformations such as projection elimination and knowledge compilation. We present a framework based on clausal tableaux suited for such tasks. These tableaux are characterized independently of particular construction methods, but important features of empirically successful methods are taken into account, especially dependency directed backjumping and branch local operation. As an instance of that framework an adaption of DPLL is described. We show that knowledge compilation methods can be essentially improved by weaving projection elimination partially into the compilation phase.
Online Handschrifterkennung chinesischer Schriftzeichen auf androidfähigen mobilen Endgeräten
(2014)
Usage of mobile dictionaries or translators requires an input. This input has to be processed and recognized beforehand. Chinese characters are more suited for a handwritten input than a keyboard based one. Reason for that are the characters consisting mostly of pictograms or ideograms.
This thesis deals with an implementation of a prototypical recognition system on a mobile device. The recognition process should be online and therefore running while writing. It can save time for the user, because suggestions are made during runtime.
Basics and an overview over the current state of the art in online handwriting recognition will be given. An approach will be chosen and implemented, such that the recognition process is fast and needs little memory. The implementation will be tested and it will show, that a fast recognition can be possible on small devices. Suggestions for expansions and improvements will be given, including a future work part.
Forwarding loops
(2013)
Die Motivation für diese Arbeit bestand darin, den Studierenden in den Rechnerpools der Universität Koblenz die Möglichkeit zu geben, mit der Simulationssoftware VNUML (Virtual Network User Mode Linux) zu arbeiten. Eingesetzt wird diese Software in den Vorlesungen und Übungen zu Rechnernetzen I und II, was eine Anwendung der Software für die Studenten unumgänglich macht. In der Vergangenheit gab es jedoch immer wieder Probleme bei der Installation und Einrichtung auf den privaten Rechnern, obwohl in früheren Studienarbeiten mehrfach vereinfachte Installationsroutinen entwickelt worden waren. Ein weiteres Problem für die Verwendung von VNUML stellt auch die Tatsache dar, dass die Software nur in einer Linux-Umgebung lauffähig ist. Da aber nicht alle Studierenden das Betriebssystem Linux benutzen und viele vor einer Installation allein zur Verwendung von VNUML zurückschrecken, war es schon länger angedacht, diese Software an den Rechnern der Universität zur Verfügung zu stellen. In dieser Arbeit wird der Prozess beschrieben, wie eine Installation der VNUML-Software in den Rechnerpools möglich war, welche Probleme dabei aufgetreten sind und welche Alternativen zur gewählten Vorgehensweise möglich gewesen wären. Das Ergebnis bietet auch eine sehr einfache Installation für den privaten Anwender, ohne dass hierfür eine eigenständige Linux-Installation nötig wäre. Auch wurden während der Entwicklung immer weitere Verbesserungen vorgenommen, welche die Anwenderfreundlichkeit der endgültigen Lösung weiter erhöhten. Die Möglichkeiten und Ideen sind dabei auch so vielfältig, dass sich die Arbeitsgruppe noch weiter mit diesem Thema beschäftigen wird und weitere Optimierungen vorgenommen werden können.
Seit Beginn des World Wide Web hat sich die Erzeugung und Verteilung digitaler Güter (digital assets) entschieden verändert. Zur Erzeugung, Bearbeitung, Verteilung und Konsumierung bedarf es heute nicht mehr spezieller physischer Gerätschaften. Dadurch hat sich die Geschwindigkeit, in der Medien generiert und transportiert werden, enorm gesteigert. Auch die Möglichkeiten der Kooperation waren dadurch einem Wandel unterlegen bzw. wurden mancherorts erst möglich gemacht.
Die Nutzung des Internets ermöglichte zwar die Loslösung digitaler Güter von ihren physischen Trägermedien, die Bestimmungen des Urheberrechts gelten jedoch weiterhin. Dies führt gerade bei juristisch weniger erfahrenen Nutzern zu Unsicherheit darüber, wie ein konkretes digitales Gut genutzt werden darf. Andererseits wird von vielen Nutzern das gewohnte Tauschen von Medien auch auf das digitale Umfeld übertragen. Die Urheberrechtsverletzungen, die zuvor im privaten Umfeld im kleinen Rahmen stattfanden, geschehen nun global und für alle sichtbar. Da diese Form des Tausches das primäre Geschäftsmodell der Verwerter gefährdet, wird versucht, die Nutzung digitaler Güter einzuschränken bzw. für nicht berechtigte Nutzer zu unterbinden. Dies geschah und geschieht unter anderem mit Verfahren der digitalen Rechte-Verwaltung (Digital Rights Management - DRM).
Diese Verfahren sind unter Nutzern bisweilen umstritten oder werden sogar offen abgelehnt, da sie die Nutzung digitaler Güter im Vergleich zum physischen Pendant erschweren können. Zudem erwiesen sich viele dieser Verfahren als nicht sicher, so dass die verwendeten Verschlüsselungsverfahren gebrochen wurden. Mit einer "Nutzungsrechte-Verwaltung" (Usage Rights Management - URM) soll DRM im Kernprinzip zwar erhalten bleiben. Die praktische Umsetzung soll aber in eine andere Richtung vorstoßen. Der Nutzer bekommt die volle Kontrolle über die digitalen Güter (ohne die restriktiven Maßnahmen klassischer DRM-Umsetzungen), aber auch wieder die volle Verantwortung. Unterstützt wird er dabei von Software, die ihn über die rechtlichen Möglichkeiten informiert und auf Wunsch des Nutzers auch software-technische Schranken in der Benutzung setzt, ähnlich der Rechtedurchsetzung (Enforcement) bei klassischen DRM-Systemen.
URM nutzt dabei die offene Rechtedefinitionssprache ODRL. Die vorliegende Studienarbeit ist Teil des URM-Projektes der Forschungsgruppe IT-Risk-Management, welches wiederum Teil des SOAVIWA-Projektes ist. Ziel der Studienarbeit ist es, eine Java-Klasse zu entwickeln, mit der in ODRL verfasste Lizenzen als Java-Objekte abgebildet werden. Weitere zu entwickelnde Komponenten sollen diese Objekte verwalten und das Modifizieren und Erzeugen neuer Objekte zulassen. Alle Komponenten sollen Bestandteil des bereits anfänglich implementierten Toolkit für URM (TURM) sein.
This diploma thesis describes the concept and implementation of a software router for policy-based Internet regulation. It is based on the ontology InFO described by Kasten and Scherp. InFO is destined for a system-independent description of regulation mechanisms. Additionally, InFO enables a transparent regulation by linking background information to the regulation mechanisms. The InFO extension RFCO extends the ontology with router-specific entities. A software router is developed to implement RFCO at the IP level. The regulation is designed to be transparent by letting the router inform affected users about the regulation measures. The router implementation is exemplarily tested in a virtual network environment.
Ein Werkzeug zur schnellen Erstellung individueller Schriftarten für die jeweiligen akuten Bedürfnisse wäre ein hilfreiches Instrument für Grafiker und Typographen. Die Anforderung für ein solches Instrument kann kaum sein, gute Schriftsätze zu erzeugen, dies liegt in den Händen des Gestalters, jedoch sollte sie jedem, der sich mit dem Thema befassen möchte, einen leichten Einstieg in die Gestaltung geben. Diese Arbeit versucht somit eine möglichst simple Lösung für das komplexe Thema der Schriftgestaltung zu liefern.
The thesis develops and evaluates a hypothetical model of the factors that influence user acceptance of weblog technology. Previous acceptance studies are reviewed, and the various models employed are discussed. The eventual model is based on the technology acceptance model (TAM) by Davis et al. It conceptualizes and operationalizes a quantitative survey conducted by means of an online questionnaire, strictly from a user perspective. Finally, it is tested and validated by applying methods of data analysis.
There are a few systems high and low-cost ones for gaze tracking. Normally low-cost systems go in hand with low-resolution cameras. Here the image quality is poor, so the algorithms for detecting the gaze have to work more precisely. But how to test and analyse them correctly, when there is a bad image quality and no reference point known? The idea of this work is, to generate synthetic eye images, where the reference points are known, because they are mainly manually set and then to test and analyse the algorithms with these synthetic images. By switching on features like gaussian noise or a second glint-like reflection point, it is possible to stepwise approximate the synthetic images close to reality. In fact the experiments will lead to an improvement of the algorithms used in a low-resolution system environment.
The annotation of digital media is no new area of research, instead it is widely investigated. There are many innovative ideas for creating the process of annotation. The most extensive segment of related work is about semi automatic annotation. One characteristic is common in the related work: None of them put the user in focus. If you want to build an interface, which is supporting and satsfying the user, you will have to do a user evaluation first. Whithin this thesis we want to analyze, which features an interface should or should not have to meet these requirements of support, user satisfaction and beeing intuitive. After collecting many ideas and arguing with a team of experts, we determined only a few of them. Different combination of these determined variables form the interfaces, we have to investigate in our usability study. The results of the usability leads to the assumption, that autocompletion and suggestion features supports the user. Furthermore coloring tags for grouping them into categories is not disturbing to the user, but has a tendency of being supportive. Same tendencies emerge for an interface consisting of two user interface elements. There is also an example given for the definition differences of being intuitive. This thesis leads to the concolusion that for reasons of user satisfaction and support it is allowed to differ from classical annotation interface features and to implement further usability studies in the section of annotation interfaces.
Ziel dieser Arbeit war es, den in [Rhe06] dargestellten operationalen Ansatz zur Modelltransformation mit Hilfe der am Institut für Softwaretechnik der Universität Koblenz-Landau vorhandenen Bibliotheken "JGraLab" und "GReQL" in Java zu implementieren. Die Implementierung sollte beweisen, dass der aufgezeigte Transformationsansatz in der Praxis umsetzbar ist. Dies wurde durch verschiedene Beispiele bewiesen. Die geplante Verwendung in weiteren Projekten des IST wird für die Zukunft zeigen, ob sich weitere Transformationen umsetzten lassen oder wo die Grenzen des Ansatzes sind. Des weiteren ist denkbar, die Transformationen nicht mehr in zwei Schritten (Schematransformation vor Graphtransformation), sondern beide Schritte auf einmal ablaufen zu lassen. Dieser Schritt setzt jedoch voraus, dass JGraLab dies ebenfalls unterstützt.
Problems in the analysis of requirements often lead to failures when developing software systems. This problem is nowadays being faced by requirements engineering. The early involvement of all kinds of stakeholders in the development of such a system and a structured process to elicitate and analyse requirements have made it a crucial factor as a first step in software development. The increasing complexity of modern softwaresystems though leads to a rising amount of information which has to be dealt with during analysis. Without the support of appropriate tools this would be almost impossible to do. Especially in bigger projects, which tend to be spatially distributed, an effective requirements engineering could not be implemented without this kind of support. Today there is a wide range of tools dealing with this matter. They have been in use since some time now and, in their most recent versions, realize the most important aspects of requirements engineering. Within the scope of this thesis some of these tools will be analysed, focussing on both the major functionalities concerning the management of requirements and the repository of these tools. The results of this analyis will be integrated into a reference model.
This thesis addresses the implementation of a particle simulation of an explosion. The simulation will be displayed via ray tracing in near real time. The implementation makes use of the openCL standard. The focus of research in this thesis is to analyse the performance of this combination of components.
This thesis deals with quality assurance of model-based SRS, in particular SRS-Models and SRS-Diagrams. The interesting thing about model-based SRS is that they are generated by a documentation generator based on the following input data: SRS-Model, SRS-Diagrams and texts external to the model. Therefore to assure the quality of the documentation the quality of their four factors must be assured, which are the SRS-Model, SRS-Diagrams, external texts and the documentation generator. The thesis" goal is to define a quality connotation for SRS-Models and -Diagrams and to show an approach for realizing automatically quality testing, measurement and assessment for the modelling tool Innovator.
German politicians have identified a need for greater citizen involvement in decision-making than in the past, as confirmed by a recent German parliamentarians study ("DEUPAS"). As in other forms of social interactions, the Internet provides significant potential to serve as the digital interface between citizens and decision-makers: in the recent past, dedicated electronic participation ("e-participation") platforms (e.g. dedicated websites) have been provided by politicians and governments in an attempt to gather citizens" feedback and comment on a particular issue or subject. Some of these have been successful, but a large proportion of them are grossly under-used " often only small numbers of citizens use them. Over the same time period, enthusiasm of Society for social networks has increased and is now commonplace. Many citizens use social networks such as Facebook and Twitter for all kinds of purposes, and in some cases to discuss political issues.
Social networks are therefore obviously attractive to politicians " from local government to federal agencies, politicians have integrated social media into their daily work. However, there is a significant challenge regarding the usefulness of social networks. The problem is the continuous increase in digital information: social networks contain vast amounts of information, and it is impossible for a human to manually filter the relevant information from the irrelevant (so-called "information overload"). Even using the search tools provided by social networks, it is still a huge task for a human to determine meanings and themes from the multitude of search results. New technologies and concepts have been proposed to provide summaries of masses of information through lexical analysis of social media messages, and therefore they promise an easy and quick overview of the information.
This thesis examines the relevance of these analyses" results, for the use in everyday political life, with the emphasis on the social networks Facebook and Twitter as data sources. Here we make use of the WeGov Toolbox and its analysis components that were developed during the EU project WeGov. The assessment has been performed in consultation with actual policy-makers from different levels of German government: policy-makers from the German Federal Parliament, the State Parliament North Rhine-Westphalia, the State Chancellery of the Saarland and the cities of Cologne and Kempten all took part in the study. Our method was to execute the analyses on data collected from Facebook and Twitter, and present the results to the policy-makers, who would then evaluate them using a mixture of qualitative methods.
The responses of the participants have provided us with some useful conclusions:
1) None of the participants believe that e-participation is possible in this way. But participants confirm that "citizen-friendliness" can be supported by this approach.
2) The most likely users for the summarisation tools are those who have experience with social networks, but are not "power users". The reason being is that "power users" already knew the relevant information provided by analysis tools. But without any experiences for social networks it is hard to interpret the analysis results the right way.
3) The evaluation has considered geographical aspects, and related this to e.g. a politician- constituency as a local area of social networks. Comparing the rural to the urban areas, it is shown that the amount of relevant political information in the rural areas is low. While the proportion of publicly available information in urban areas is relatively high, the proportion in the rural areas is much lower.
The findings that result from the engagement with policy-makers will be systematically surveyed and validated within this thesis.
In der vorliegenden Arbeit wird die Integration einer Business Intelligence-Lösung in eine bestehende Social Software beschrieben. Dafür wird zunächst der Begriff Business Intelligence und Social Software, der Aufbau sowie deren Bestandteile näher erläutert. Danach erfolgt eine Analyse der IST-Situation der Zielgruppe durch Interviews, deren Auswertungen in der SOLL-Konzeptionierung in eine Anforderungsliste transformiert werden. Abschließend werden die herausgearbeiteten Anforderungen an der finalen Installation geprüft und getestet, um festzustellen ob die Erwartungen der Zielgruppe und ihre Vorstellungen von Business Intelligence realisierbar sind.
Das Ergebnis dieser Arbeit soll eine installierte Business Intelligence-Lösung in einer Social Software sein. Diese soll einen Überblick darüber geben, was mit der aktuellsten Version der Software bereits möglich ist und kritisch aufzeigen, wo es Stärken und Schwächen gibt, die bei zukünftigen Versionenrnbedacht werden sollten.
Retrospektive Analyse der Ausbreitung und dynamische Erkennung von Web-Tracking durch Sandboxing
(2018)
Aktuelle quantitative Analysen von Web-Tracking bieten keinen umfassenden Überblick über dessen Entstehung, Ausbreitung und Entwicklung. Diese Arbeit ermöglicht durch Auswertung archivierter Webseiten eine rückblickende Erfassung der Entstehungsgeschichte des Web-Trackings zwischen den Jahren 2000 und 2015. Zu diesem Zweck wurde ein geeignetes Werkzeug entworfen, implementiert, evaluiert und zur Analyse von 10000 Webseiten eingesetzt. Während im Jahr 2005 durchschnittlich 1,17 Ressourcen von Drittparteien eingebettet wurden, zeigt sich ein Anstieg auf 6,61 in den darauffolgenden 10 Jahren. Netzwerkdiagramme visualisieren den Trend zu einer monopolisierten Netzstruktur, in der bereits ein einzelnes Unternehmen 80 % der Internetnutzung überwachen kann.
Trotz vielfältiger Versuche, dieser Entwicklung durch technische Maßnahmen entgegenzuwirken, erweisen sich nur wenige Selbst- und Systemschutzmaßnahmen als wirkungsvoll. Diese gehen häufig mit einem Verlust der Funktionsfähigkeit einer Webseite oder mit einer Einschränkung der Nutzbarkeit des Browsers einher. Mit der vorgestellten Studie wird belegt, dass rechtliche Vorschriften ebenfalls keinen hinreichenden Schutz bieten. An Webauftritten von Bildungseinrichtungen werden Mängel bei Erfüllung der datenschutzrechtlichen Pflichten festgestellt. Diese zeigen sich durch fehlende, fehlerhafte oder unvollständige Datenschutzerklärungen, deren Bereitstellung zu den Informationspflichten eines Diensteanbieters gehören.
Die alleinige Berücksichtigung klassischer Tracker ist nicht ausreichend, wie mit einer weiteren Studie nachgewiesen wird. Durch die offene Bereitstellung funktionaler Webseitenbestandteile kann ein Tracking-Unternehmen die Abdeckung von 38 % auf 61 % erhöhen. Diese Situation wird durch Messungen von Webseiten aus dem Gesundheitswesen belegt und aus technischer sowie rechtlicher Perspektive bewertet.
Bestehende systemische Werkzeuge zum Erfassen von Web-Tracking verwenden für ihre Messung die Schnittstellen der Browser. In der vorliegenden Arbeit wird mit DisTrack ein Framework zur Web-Tracking-Analyse vorgestellt, welches eine Sandbox-basierte Messmethodik verfolgt. Dies ist eine Vorgehensweise, die in der dynamischen Schadsoftwareanalyse erfolgreich eingesetzt wird und sich auf das Erkennen von Seiteneffekten auf das umliegende System spezialisiert. Durch diese Verhaltensanalyse, die unabhängig von den Schnittstellen des Browsers operiert, wird eine ganzheitliche Untersuchung des Browsers ermöglicht. Auf diese Weise können systemische Schwachstellen im Browser aufgezeigt werden, die für speicherbasierte Web-Tracking-Verfahren nutzbar sind.
Model-Driven Engineering (MDE) aims to raise the level of abstraction in software system specifications and increase automation in software development. Modelware technological spaces contain the languages and tools for MDE that software developers take into consideration to model systems and domains. Ontoware technological spaces contain ontology languages and technologies to design, query, and reason on knowledge. With the advent of the Semantic Web, ontologies are now being used within the field of software development, as well. In this thesis, bridging technologies are developed to combine two technological spaces in general. Transformation bridges translate models between spaces, mapping bridges relate different models between two spaces, and, integration bridges merge spaces to new all-embracing technological spaces. API bridges establish interoperability between the tools used in the space. In particular, this thesis focuses on the combination of modelware and ontoware technological spaces. Subsequent to a sound comparison of languages and tools in both spaces, the integration bridge is used to build a common technological space, which allows for the hybrid use of languages and the interoperable use of tools. The new space allows for language and domain engineering. Ontology-based software languages may be designed in the new space where syntax and formal semantics are defined with the support of ontology languages, and the correctness of language models is ensured by the use of ontology reasoning technologies. These languages represent a core means for exploiting expressive ontology reasoning in the software modeling domain, while remaining flexible enough to accommodate varying needs of software modelers. Application domains are conceptually described by languages that allow for defining domain instances and types within one domain model. Integrated ontology languages may provide formal semantics for domain-specific languages and ontology technologies allow for reasoning over types and instances in domain models. A scenario in which configurations for network device families are modeled illustrates the approaches discussed in this thesis. Furthermore, the implementation of all bridging technologies for the combination of technological spaces and all tools for ontology-based language engineering and use is illustrated.
This work represents a quantitative analysis and visualisation of scar tissue of the left ventricular myocard. The scar information is shown in the late enhancement data, that highlights the avitale tissue with the help of a contrast agent. Through automatic methods, the scar is extracted from the image data and quantifies the size, location and transmurality. The transmurality shows a local measurement between the heart wall und the width of the scar. The developed methods help the cardiologist to analyse the measurement, the reason and the degree of the heart failure in a short time period. He can further control the results by several visual presentations. The deformation of the scar tissue over the heart cycle is implemented in another scientific work. A visual improvement of the deformation result which extracts the scar out of the data is aspired. The avital tissue is shown in a more comfortable way by eliminating the unnecessary image information and therefore improves the visual analysis of the pumping heart. Both methods show a detailed analysis of the scar tissue. This supports the clinic practical throughout the manual analysis.
Towards Improving the Understanding of Image Semantics by Gaze-based Tag-to-Region Assignments
(2011)
Eye-trackers have been used in the past to identify visual foci in images, find task-related image regions, or localize affective regions in images. However, they have not been used for identifying specific objects in images. In this paper, we investigate whether it is possible to assign image regions showing specific objects with tags describing these objects by analyzing the users' gaze paths. To this end, we have conducted an experiment with 20 subjects viewing 50 image-tag-pairs each. We have compared the tag-to-region assignments for nine existing and four new fixation measures. In addition, we have investigated the impact of extending region boundaries, weighting small image regions, and the number of subjects viewing the images. The paper shows that a tag-to-region assignment with an accuracy of 67% can be achieved by using gaze information. In addition, we show that multiple regions on the same image can be differentiated with an accuracy of 38%.
The availability of digital cameras and the possibility to take photos at no cost lead to an increasing amount of digital photos online and on private computers. The pure amount of data makes approaches that support users in the administration of the photo necessary. As the automatic understanding of photo content is still an unsolved task, metadata is needed for supporting administrative tasks like search or photo work such as the generation of photo books. Meta-information textually describes the depicted scene or consists of information on how good or interesting a photo is.
In this thesis, an approach for creating meta-information without additional effort for the user is investigated. Eye tracking data is used to measure the human visual attention. This attention is analyzed with the objective of information creation in the form of metadata. The gaze paths of users working with photos are recorded, for example, while they are searching for photos or while they are just viewing photo collections.
Eye tracking hardware is developing fast within the last years. Because of falling prices for sensor hardware such as cameras and more competition on the eye tracker market, the prices are falling, and the usability is increasing. It can be assumed that eye tracking technology can soon be used in everyday devices such as laptops or mobile phones. The exploitation of data, recorded in the background while the user is performing daily tasks with photos, has great potential to generate information without additional effort for the users.
The first part of this work deals with the labeling of image region by means of gaze data for describing the depicted scenes in detail. Labeling takes place by assigning object names to specific photo regions. In total, three experiments were conducted for investigating the quality of these assignments in different contexts. In the first experiment, users decided whether a given object can be seen on a photo by pressing a button. In the second study, participants searched for specific photos in an image search application. In the third experiment, gaze data was collected from users playing a game with the task to classify photos regarding given categories. The results of the experiments showed that gaze-based region labeling outperforms baseline approaches in various contexts. In the second part, most important photos in a collection of photos are identified by means of visual attention for the creation of individual photo selections. Users freely viewed photos of a collection without any specific instruction on what to fixate, while their gaze paths were recorded. By comparing gaze-based and baseline photo selections to manually created selections, the worth of eye tracking data in the identification of important photos is shown. In the analysis of the data, the characteristics of gaze data has to be considered, for example, inaccurate and ambiguous data. The aggregation of gaze data, collected from several users, is one suggested approach for dealing with this kind of data.
The results of the performed experiments show the value of gaze data as source of information. It allows to benefit from human abilities where algorithms still have problems to perform satisfyingly.
Traditional Driver Assistance Systems (DAS) like for example Lane Departure Warning Systems or the well-known Electronic Stability Program have in common that their system and software architecture is static. This means that neither the number and topology of Electronic Control Units (ECUs) nor the presence and functionality of software modules changes after the vehicles leave the factory.
However, some future DAS do face changes at runtime. This is true for example for truck and trailer DAS as their hardware components and software entities are spread over both parts of the combination. These new requirements cannot be faced by state-of-the-art approaches of automotive software systems. Instead, a different technique of designing such Distributed Driver Assistance Systems (DDAS) needs to be developed. The main contribution of this thesis is the development of a novel software and system architecture for dynamically changing DAS using the example of driving assistance for truck and trailer. This architecture has to be able to autonomously detect and handle changes within the topology. In order to do so, the system decides which degree of assistance and which types of HMI can be offered every time a trailer is connected or disconnected. Therefore an analysis of the available software and hardware components as well as a determination of possible assistance functionality and a re-configuration of the system take place. Such adaptation can be granted by the principles of Service-oriented Architecture (SOA). In this architectural style all functionality is encapsulated in self-contained units, so-called Services. These Services offer the functionality through well-defined interfaces whose behavior is described in contracts. Using these Services, large-scale applications can be built and adapted at runtime. This thesis describes the research conducted in achieving the goals described by introducing Service-oriented Architectures into the automotive domain. SOA deals with the high degree of distribution, the demand for re-usability and the heterogeneity of the needed components.
It also applies automatic re-configuration in the event of a system change. Instead of adapting one of the frameworks available to this scenario, the main principles of Service-orientation are picked up and tailored. This leads to the development of the Service-oriented Driver Assistance (SODA) framework, which implements the benefits of Service-orientation while ensuring compatibility and compliance to automotive requirements, best-practices and standards. Within this thesis several state-of-the-art Service-oriented frameworks are analyzed and compared. Furthermore, the SODA framework as well as all its different aspects regarding the automotive software domain are described in detail. These aspects include a well-defined reference model that introduces and relates terms and concepts and defines an architectural blueprint. Furthermore, some of the modules of this blueprint such as the re-configuration module and the Communication Model are presented in full detail. In order to prove the compliance of the framework regarding state-of-the-art automotive software systems, a development process respecting today's best practices in automotive design procedures as well as the integration of SODA into the AUTOSAR standard are discussed. Finally, the SODA framework is used to build a full-scale demonstrator in order to evaluate its performance and efficiency.