Refine
Document Type
- Bachelor Thesis (68) (remove)
Keywords
- Android <Systemplattform> (3)
- Routing (3)
- Akkreditierung (2)
- E-Government (2)
- Enterprise 2.0 (2)
- Smartphone (2)
- 3D-Kartierung (1)
- API (1)
- Ad-Hoc Routing (1)
- Agenten (1)
Institute
- Fachbereich 4 (68) (remove)
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.
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.
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.
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 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.
This bachelor thesis deals with the topic "user-friendly design of applications (apps)" on mobile devices, a subdomain of software-ergonomics. In the process, two applications are being analyzed with the aim of developing a solution on how support on a mobile device should be conducted. This study focuses primarily on appropriate gestures to coordinate the 'help function' on a mobile device. The study results show that the test persons request a customized help function, but reject an extensive help description, as this seems to be overwhelming for the user.
The measurement of the benefits of collaborative technologies is a challenge caused by sociological influences on these systems. In this work, the introduction of a collaborative system into an existing IT environment is examined, so that a value can be identified for the company. The analysis of frameworks has shown that the benefits can be reaped through better management and organization of in-company resources and optimization of the underlying process.
The RoboCup Rescue League was founded with the intention to serve as an international communication platform for development of rescue robots. In regions hit by catastrophes, those robots are meant to find buried people, detect their physical condition and send the proper information to rescue teams.
At the university of Koblenz the rescue robot "Robbie" has been in development for years. Robbie accumulates information about his environment by targeted control of sensors and can act autonomous in unknown regions with help of the previous collected data. He creates an internal 2D map of his environment. This map provides enough information to navigate through space and to localize himself. Unfortunately, 2D maps have a huge drawback. When confronted with uneven terrain or even multilayered disaster areas, this technique will meet its limitations. Considered that most afflicted areas will probably have a bumpy ground, it is important to improve this technique.
That is why 3D-mapping is being required. With the help of RoboCup Rescue Scenario this Bachelor Thesis is going to implement a 3D-mapping algorithm and evaluate the flaws of 2D- and 3D-mapping problems thoroughly.
In this study, the author evaluates four visualization methods (FlexViz, the Jambalaya applet, Experimental jOWL TouchGraph, and Plone ontology) from the pool of currently available web based visualization methods.
Further, this study attempts to answer of the following research questions: 1. What are the requirements for ontology visualization? 2. How is comparative analysis and evaluation carried out? 3. How can a chosen method be tested? Based on the results of the evaluation, the visualization method FlexViz was found to be the most suitable for the given scenario. The deployment of FlexViz was carried out and integrated within Plone CMS and logical parts of the VCD ontology are tested. Finally, FlexViz was analyzed from different stakeholder- perspectives. Results showed that FleViz is a reliable tool for visualizing, understanding and analyzing a developed ontology because of its user-friendly and interactive interface, but performs poorly in regards to the editing, extension and development process.
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.