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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.
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.
Diese Masterarbeit beschreibt und evaluiert die im Rahmen der Arbeit entwickelten Erweiterungen zur Schellings Segregationsimulation. Der Nobelpreisträger Thomas C. Schelling simulierte als erster ab 1969 die Segregation. Die dabei entstandenen Ergebnisse erlaubten eine genauere Analyse der auftretenden Phänomene. Uri Wilensky, Mitarbeiter der "Northwestern University", entwickelte seit 1999 eine Segregationssimulation in NetLogo.
Im Rahmen meiner Masterarbeit habe ich das NetLogo-Model von Uri Wilensky in sechs unterschiedlichen Szenarien weiterentwickelt.
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.
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.
Gartner predicts that 33 per cent of total accesses to Business Intelligence (BI) functionalities will be done until 2013 using mobile devices. While mobile devices have already spread to a high extent in private life they have recently become more and more part of the professional life as well and businesses are seeking to develop smart scenarios on how to integrate the new technologies in their processes. The development of mobile software applications is also booming in the field of BI. The research topic of Mobile Business Intelligence (mBI) is focussing on how to expand traditional BI concepts to the new mobility dimension thus enabling to apply BI functionalities on mobile devices, such as smartphones and tablet computers. The increasing significance of mBI for research in combination with the tremendous economic growth potential forecasted for the next years is the driver for writing this thesis. The main aspect of the present thesis is a concept on how to develop a consistent mBI Strategy aligning all structures, processes and stakeholders to one standard set of goals and guidelines. Crucial points when implementing an mBI strategy are the definition of goals, the identification of risks and opportunities, the adaptation of mBI to the user context, the integration of mBI into the existing IT landscape, as well as a proper set-up of system architectures and security concepts. Besides analyzing the aspect of mBI strategy this thesis also considers the market situation of mBI. Clearly defined goals and the systematic development of a consistent mBI strategy which is in line with these goals can be considered as a crucial prerequisite for companies to successfully implement mBI.
In this thesis the possibilities for real-time visualization of OpenVDB
files are investigated. The basics of OpenVDB, its possibilities, as well
as NanoVDB and its GPU port, were studied. A system was developed
using PNanoVDB, the graphics API port of OpenVDB. Techniques were
explored to improve and accelerate a single ray approach of ray tracing.
To prove real-time capability, two single scattering approaches were
also implemented. One of these was selected, further investigated and
optimized to achieve interactive real-time rendering.
It is important to give artists immediate feedback on their adjustments, as
well as the possibility to change all parameters to ensure a user friendly
creation process.
In addition to the optical rendering, corresponding benchmarks were
collected to compare different improvement approaches and to prove
their relevance. Attention was paid to the rendering times and memory
consumption on the GPU to ensure optimal use. A special focus, when
rendering OpenVDB files, was put on the integrability and extensibility of
the program to allow easy integration into an existing real-time renderer
like U-Render.
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.
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.
Opinion Mining : Using Twitter as a source of opinion for the prediction of stock market prices
(2012)
Neben den theoretischen Grundkonzepten der automatisierten Fließtextanalyse, die das Fundament dieser Arbeit bilden, soll ein Überblick in den derzeitigen Forschungsstand bei der Analyse von Twitter-Nachrichten gegeben werden. Hierzu werden verschiedene Forschungsergebnisse der, derzeit verfügbaren wissenschaftlichen Literatur erläutert, miteinander verglichen und kritisch hinterfragt. Deren Ergebnisse und Vorgehensweisen sollen in unsere eigene Forschung mit eingehen, soweit sie sinnvoll erscheinen. Ziel ist es hierbei, den derzeitigen Forschungsstand möglichst gut zu nutzen.
Ein weiteres Ziel ist es, dem Leser einen Überblick über verschiedene maschinelle Datenanalysemethoden zur Erkennung von Meinungen zu geben. Dies ist notwendig, um die Bedeutung der im späteren Verlauf der Arbeit eingesetzten Analysemethoden in ihrem wissenschaftlichen Kontext besser verstehen zu können. Da diese Methoden auf verschiedene Arten durchgeführt werden können, werden verschiedene Analysemethoden vorgestellt und miteinander verglichen. Hierdurch soll die Machbarkeit der folgenden Meinungsauswertung bewiesen werden. Um eine hinreichende Genauigkeit bei der folgenden Untersuchung zu gewährleisten, wird auf ein bereits bestehendes und evaluiertes Framework zurückgegriffen. Dieses ist als API 1 verfügbar und wird daher zusätzlich behandelt. Der Kern Inhalt dieser Arbeit wird sich der Analyse von Twitternachrichten mit den Methoden des Opinion Mining widmen.
Es soll untersucht werden, ob sich Korrelationen zwischen der Meinungsausprägung von Twitternachrichten und dem Börsenkurs eines Unternehmens finden lassen. Es soll dabei die Stimmungslage der Firma Google Inc. über einen Zeitraum von einem Monat untersucht und die dadurch gefunden Erkenntnisse mit dem Börsenkurs des Unternehmens verglichen werden. Ziel ist es, die Erkenntnisse von (Sprenger & Welpe, 2010) und (Taytal & Komaragiri, 2009) auf diesem Gebiet zu überprüfen und weitere Fragestellungen zu beantworten.
Particle swarm optimization is an optimization technique based on simulation of the social behavior of swarms.
The goal of this thesis is to solve 6DOF local pose estimation using a modified particle swarm technique introduced by Khan et al. in 2010. Local pose estimation is achieved by using continuous depth and color data from a RGB-D sensor. Datasets are aquired from different camera poses and registered into a common model. Accuracy and computation time of the implementation is compared to state of the art algorithms and evaluated in different configurations.
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.
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.
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.
Identifying reusable legacy code able to implement SOA services is still an open research issue. This master thesis presents an approach to identify legacy code for service implementation based on dynamic analysis and the application of data mining techniques. rnrnAs part of the SOAMIG project, code execution traces were mapped to business processes. Due to the high amount of traces generated by dynamic analyses, the traces must be post-processed in order to provide useful information. rnrnFor this master thesis, two data mining techniques - cluster analysis and link analysis - were applied to the traces. First tests on a Java/Swing legacy system provided good results, compared to an expert- allocation of legacy code.
The purpose of this master thesis is to enable the Robot Lisa to process complex commands and extract the necessary information in order to perform a complex task as a sequence of smaller tasks. This is intended to be achieved by the improvement of the understanding that Lisa has of her environment by adding semantics to the maps that she builds. The complex command itself will be expected to be already parsed. Therefore the way the input is processed to become a parsed command is out of the scope of this work. Maps that Lisa builds will be improved by the addition of semantic annotations that can include any kind of information that might be useful for the performance of generic tasks. This can include (but not necessarily limited to) hierarchical classifications of locations, objects and surfaces. The processing of the command in addition to some information of the environment shall trigger the performance of a sequence of actions. These actions are expected to be included in Lisa- currently implemented tasks and will rely on the currently existing modules that perform them.
Nevertheless the aim of this work is not only to be able to use currently implemented tasks in a more complex sequence of actions but also make it easier to add new tasks to the complex commands that Lisa can perform.
Pedestrian Detection in digital images is a task of huge importance for the development of automaticsystems and in improving the interaction of computer systems with their environment. The challenges such a system has to overcome are the high variance of the pedestrians to be recognized and the unstructured environment. For this thesis, a complete system for pedestrian detection was implemented according to a state of the art technique. A novel insight about precomputing the Color Self-Similarity accelerates the computations by a factor of four. The complete detection system is described and evaluated, and was published under an open source license.
On-screen interactive presentations have got immense popularity in the domain of attentive interfaces recently. These attentive screens adapt their behavior according to the user's visual attention. This thesis aims to introduce an application that would enable these attentive interfaces to change their behavior not just according to the gaze data but also facial features and expressions. The modern era requires new ways of communications and publications for advertisement. These ads need to be more specific according to people's interests, age, and gender. When advertising, it's important to get a reaction from the user but not every user is interested in providing feedback. In such a context more, advance techniques are required that would collect user's feedback effortlessly. The main problem this thesis intends to resolve is, to apply advanced techniques of gaze and face recognition to collect data about user's reactions towards different ads being played on interactive screens. We aim to create an application that enables attentive screens to detect a person's facial features, expressions, and eye gaze. With eye gaze data we can determine the interests and with facial features, age and gender can be specified. All this information will help in optimizing the advertisements.
In a software reengineering task legacy systems are adapted computer-aided to new requirements. For this an efficient representation of all data and information is needed. TGraphs are a suitable representation because all vertices and edges are typed and may have attributes. Further more there exists a global sequence of all graph elements and for each vertex exists a sequence of all incidences. In this thesis the "Extractor Description Language" (EDL) was developed. It can be used to generate an extractor out of a syntax description, which is extended by semantic actions. The generated extractor can be used to create a TGraph representation of the input data. In contrast to classical parser generators EDL support ambiguous grammars, modularization, symbol table stacks and island grammars. These features simplify the creation of the syntax description. The collected requirements for EDL are used to determine an existing parser generator which is suitable to realize the requirements.
After that the syntax and semantics of EDL are described and implemented using the suitable parser generator. Following two extractors one for XML and one for Java are created with help of EDL. Finally the time they need to process some input data is measured.
In this master thesis some new helpful features will be added to the Spanning Tree Simulator. This simulator was created by Andreas Sebastian Janke in his bachelor thesis [Jan10b] in 2010. It is possible to visualize networks which are defined in a configuration file. Each of them is a XML representation of a network consisting of switches and hosts. After loading such a file into the program it is possible to run the Spanning Tree Algorithm IEEE 802.1D. In contrast to the previous version only the switches are implemented as threads. When the algorithm is finished a spanning tree is built. This means, that messages cannot run into loops anymore. This is important because loops can cause a total breakdown of the communication in a network, if the running routing protocols cannot handle loops.