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This paper describes the robots TIAGo and Lisa used by
team homer@UniKoblenz of the University of Koblenz-Landau, Germany,
for the participation at the RoboCup@Home 2019 in Sydney,
Australia. We ended up first at RoboCup@Home 2019 in the Open Platform
League and won the competition in our league now three times
in a row (four times in total) which makes our team the most successful
in RoboCup@Home. We demonstrated approaches for learning from
demonstration, touch enforcing manipulation and autonomous semantic
exploration in the finals. A special focus is put on novel system components
and the open source contributions of our team. We have released
packages for object recognition, a robot face including speech synthesis,
mapping and navigation, speech recognition interface, gesture recognition
and imitation learning. The packages are available (and new packages
will be released) on http://homer.uni-koblenz.de.
This paper describes the robots TIAGo and Lisa used by team homer@UniKoblenz of the University of Koblenz-Landau, Germany, for the participation at the RoboCup@Home 2018 in Montreal, Canada. Further this paper serves as qualification material for the RoboCup-@Home participation in 2018. A special focus is put on novel system components and the open source contributions of our team. This year the team from Koblenz won the biggest annual scientianc robot competition in Montreal in the RoboCup@Home Open Platform track for the third time and also won the RoboCup@Home German Open for the second time. As a research highlight a novel symbolic imitation learning approach was demonstrated during the annals. The TIAGo robotic research platform was used for the first time by the team. We have released packages for object recognition, a robot face including speech synthesis, mapping and navigation, speech recognition interface via android and a GUI. The packages are available (and new packages will be released) on http://wiki.ros.org/agas-ros-pkg. Further information can be found on our project page http://homer.uni-koblenz.de.
Efficient Cochlear Implant (CI) surgery requires prior knowledge of the cochlea’s size and its characteristics. This information helps to select suitable implants for different patients. Registered and fused images helps doctors by providing more informative image that takes advantages of different modalities. The cochlea’s small size and complex structure, in addition to the different resolutions and head positions during imaging, reveals a big challenge for the automated registration of the different image modalities. To obtain an automatic measurement of the cochlea length and the volume size, a segmentation method of cochlea medical images is needed. The goal of this dissertation is to introduce new practical and automatic algorithms for the human cochlea multi-modal 3D image registration, fusion, segmentation and analysis. Two novel methods for automatic cochlea image registration (ACIR) and automatic cochlea analysis (ACA) are introduced. The proposed methods crop the input images to the cochlea part and then align the cropped images to obtain the optimal transformation. After that, this transformation is used to align the original images. ACIR and ACA use Mattes mutual information as similarity metric, the adaptive stochastic gradient descent (ASGD) or the stochastic limited memory Broyden–Fletcher–Goldfarb–Shanno (s-LBFGS) optimizer to estimate the parameters of 3D rigid transform. The second stage of nonrigid registration estimates B-spline coefficients that are used in an atlas-model-based segmentation to extract cochlea scalae and the relative measurements of the input image. The image which has segmentation is aligned to the input image to obtain the non-rigid transformation. After that the segmentation of the first image, in addition to point-models are transformed to the input image. The detailed transformed segmentation provides the scala volume size. Using the transformed point-models, the A-value, the central scala lengths, the lateral and the organ of corti scala tympani lengths are computed. The methods have been tested using clinical 3D images of total 67 patients: from Germany (41 patients) and Egypt (26 patients). The atients are of different ages and gender. The number of images used in the experiments is 217, which are multi-modal 3D clinical images from CT, CBCT, and MRI scanners. The proposed methods are compared to the state of the arts ptimizers related medical image registration methods e.g. fast adaptive stochastic gradient descent (FASGD) and efficient preconditioned tochastic gradient descent (EPSGD). The comparison used the root mean squared distance (RMSE) between the ground truth landmarks and the resulted landmarks. The landmarks are located manually by two experts to represent the round window and the top of the cochlea. After obtaining the transformation using ACIR, the landmarks of the moving image are transformed using the resulted transformation and RMSE of the transformed landmarks, and at the same time the fixed image landmarks are computed. I also used the active length of the cochlea implant electrodes to compute the error aroused by the image artifact, and I found out an error ranged from 0.5 mm to 1.12 mm. ACIR method’s RMSE average was 0.36 mm with a standard deviation (SD) of 0.17 mm. The total time average required for registration of an image pair using ACIR was 4.62 seconds with SD of 1.19 seconds. All experiments are repeated 3 times for justifications. Comparing the RMSE of ACIR2017 and ACIR2020 using paired T-test shows no significant difference (p-value = 0.17). The total RMSE average of ACA method was 0.61 mm with a SD of 0.22 mm. The total time average required for analysing an image was 5.21 seconds with SD of 0.93 seconds. The statistical tests show that there is no difference between the results from automatic A-value method and the manual A-value method (p-value = 0.42). There is no difference also between length’s measurements of the left and the right ear sides (p-value > 0.16). Comparing the results from German and Egypt dataset shows there is no difference when using manual or automatic A-value methods (p-value > 0.20). However, there is a significant difference when using ACA2000 method between the German and the Egyptian results (p-value < 0.001). The average time to obtain the segmentation and all measurements was 5.21 second per image. The cochlea scala tympani volume size ranged from 38.98 mm3 to 57.67 mm3 . The combined scala media and scala vestibuli volume size ranged from 34.98 mm 3 to 49.3 mm 3 . The overall volume size of the cochlea should range from 73.96 mm 3 to 106.97 mm 3 . The lateral wall length of scala tympani ranged from 42.93 mm to 47.19 mm. The organ-of-Corti length of scala tympani ranged from 31.11 mm to 34.08 mm. Using the A-value method, the lateral length of scala tympani ranged from 36.69 mm to 45.91 mm. The organ-of-Corti length of scala tympani ranged from 29.12 mm to 39.05 mm. The length from ACA2020 method can be visualised and has a well-defined endpoints. The ACA2020 method works on different modalities and different images despite the noise level or the resolution. In the other hand, the A-value method works neither on MRI nor noisy images. Hence, ACA2020 method may provide more reliable and accurate measurement than the A-value method. The source-code and the datasets are made publicly available to help reproduction and validation of my result.
In der vorliegenden Arbeit werden gamebasierte touristische Anwendungen untersucht.
Ausgehend von der These, dass für touristisches Freizeiterleben primär intrinsisch motivierende Anwendungen geeignet sind, werden zunächst intrinsische Motivationskonzepte untersucht. Dazu wird untersucht, wie Motivation gezielt herbeigeführt werden kann und ob sich gamebasierte Motivationskonzepte auf nichtspielerische Anwendungen übertragen lassen.
Darauf aufbauend wurden im Rahmen dieser Arbeit verschiedene touristische Anwendungen entwickelt und evaluiert. Ziel dieser Anwendungen ist es stets, einen Mehrwert für das touristische Freizeiterleben zu erzeugen. Die Anwendungen werden nach ihrer Mobilität kategorisiert. Es werden vollständig mobile, vollständig stationäre und hybride Systeme untersucht. Als Mehrwertkomponenten werden in dieser Arbeit spielbasierte Exploration einer Umgebung, Wissensvermittlung und soziale Interaktion zwischen Touristen untersucht.
Abschließend wird ein Autorentool für spielbasierte touristische Touren auf Smartphones entwickelt und untersucht, das seinerseits auf spielbasierte Elemente zurückgreift. Das Ziel dieses Systems ist es, Konzepte zu entwickeln, die beispielsweise eine Integration in soziale Netzwerke erlauben.
Six and Gimmler have identified concrete capabilities that enable users to use the Internet in a competent way. Their media competence model can be used for the didactical design of media usage in secondary schools. However, the special challenge of security awareness is not addressed by the model. In this paper, the important dimension of risk and risk assessment will be introduced into the model. This is especially relevant for the risk of the protection of personal data and privacy. This paper will apply the method of IT risk analysis in order to select those dimensions of the Six/Gimmler media competence model that are appropriate to describe privacy aware Internet usage. Privacy risk aware decisions for or against the Internet usage is made visible by the trust model of Mayer et al.. The privacy extension of the competence model will lead to a measurement of the existing privacy awareness in secondary schools, which, in turn, can serve as a didactically well-reasoned design of Informatics modules in secondary schools. This paper will provide the privacy-extended competence model, while empirical measurement and module design is planned for further research activities.
This paper describes the robot Lisa used by team homer@UniKoblenz of the University of Koblenz Landau, Germany, for the participation at the RoboCup@Home 2017 in Nagoya, Japan. A special focus is put on novel system components and the open source contributions of our team. We have released packages for object recognition, a robot face including speech synthesis, mapping and navigation, speech recognition interface via android and a GUI. The packages are available (and new packages will be released) on
http://wiki.ros.org/agas-ros-pkg.
In recent years head mounted displays (HMD) and their abilities to create virtual realities comparable with the real world moved more into the focus of press coverage and consumers. The reason for this lies in constant improvements in available computing power, miniaturisation of components as well as the constantly shrinking power consumption. These trends originate in the general technical progress driven by advancements made in smartphone sector. This gives more people than ever access to the required components to create these virtual realities. However at the same time there is only limited research which uses the current generation of HMDs especially when comparing the virtual and real world against each other. The approach of this thesis is to look into the process of navigating both real and virtual spaces while using modern hardware and software. One of the key areas are the spatial and peripheral perception without which it would be difficult to navigate a given space. The influence of prior real and virtual experiences on these will be another key aspect. The final area of focus is the influence on the emotional state and how it compares to the real world. To research these influences a experiment using the Oculus Rift DK2 HMD will be held in which subjects will be guided through a real space as well as a virtual model of it. Data will be gather in a quantitative manner by using surveys. Finally, the findings will be discussed based on a statistical evaluation. During these tests the different perception of distances and room size will the compared and how they change based on the current reality. Furthermore, the influence of prior spatial activities both in the real and the virtual world will looked into. Lastly, it will be checked how real these virtual worlds are and if they are sufficiently sophisticated to trigger the same emotional responses as the real world.
Tracking ist ein zentraler Bestandteil vieler moderner technischer Anwendungen, insbesondere in den Bereichen autonome Systeme und Augmented Reality. Für Tracking gibt es viele unterschiedliche Ansätze. Ein erst seit kurzem verfolgter ist die Verwendung von Neuronalen Netzen. Im Rahmen dieser Masterarbeit wird eine eine Anwendung erstellt, welche für das Tracking ein Neuronales Netz verwendet. Dazu gehört ebenfalls die Erstellung von Trainingsdaten, sowie die Erstellung des Neuronalen Netzes und dessen Training.
Anschließend wird die Verwendung von Neuronalen Netzen für Tracking analysiert und ausgewertet. Hierunter fallen verschiedene Aspekte. Es wird für eine unterschiedliche Anzahl an Freiheitsgraden geprüft wie gut das Tracking funktioniert und wie viel Performance dieser Ansatz kostet. Des Weiteren wird die Menge der benötigten Trainingsdaten untersucht, der Einfluss der Architektur des Netzwerks und wie wichtig das Vorhandensein von Tiefendaten für die Funktion des Trackings ist. Dies soll einen Einblick ermöglichen wie relevant dieser Ansatz für den Einsatz in zukünftigen Produkten sein könnte.
Augmented Reality besitzt viele denkbare Anwendungsbereiche, in denen Alltag oder Arbeitsprozesse vereinfacht werden können. Dadurch, dass viele Hersteller sehr unterschiedliche Augmented Reality Brillen anbieten, wird die Auswahl des richtigen Systems und eine systemübergreifende Entwicklung jedoch erschwert. Im Rahmen dieser Bachelorarbeit wird daher eine Anwendung entwickelt, mit der Augmented Reality Brillen auf einem Virtual Reality System simuliert werden können. Damit soll eine plattformübergreifende Entwicklung sowie die Auswahl des richtigen Systems vereinfacht werden.
Da die Simulation für mobile Endgeräte konzipiert werden soll, sollen möglichst realistische Umgebungen als Panorama vorgerendert werden können. Um diese auf Virtual Reality Systemen als stereoskopische Bilder darstellen zu können, werden verschiedene Verfahren zur Konvertierung in solche vorgestellt. Es wird ein Editor entwickelt, mit dem verschiedene Szenarien erstellt, Augmented Reality Systeme konfiguriert und schließlich auf einem Virtual Reality System angezeigt werden können. Abschließend wird untersucht, wie gut die Simulation gelungen ist und welche Verbesserungsmöglichkeiten es gibt.
In dieser Bachelorarbeit wird ein Simulationscode für astrophysikalische
Simulationen von Fluiden unter dem Einfluss ihrer eigenen
Gravitation entwickelt. Der Code wird hauptsächlich von der GPU
ausgeführt. Leichte Vereinfachungen der physikalischen Modelle und
einige Parameter zum Steuern von Genauigkeit und Rechenaufwand
ermöglichen das Simulieren mit interaktiver Bildwiederholrate auf den
meisten handelsüblichen, modernen Computern mit einer dedizierten
Grafikkarte. Der Simulationscode wird verwendet, um die Entstehung
von Sternen aus einer Gaswolke zu simulieren. Einige Merkmale der
Sternentstehung, wie zum Beispiel Akkretionsscheiben und Fragmentierung,
lassen sich selbst bei niedrigen Partikelzahlen beobachten.