Deggendorf University of Applied Sciences

www.hdu-deggendorf.de/404
Deggendorf, Germany
SEARCH FILTERS
Time filter
Source Type

Futterer G.,Deggendorf University of Applied Sciences
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

Applications, which can profit from holographic 3D displays, are the visualization of 3D data, computer-integrated manufacturing, 3D teleconferencing and mobile infotainment. However, one problem of holographic 3D displays, which are e.g. based on space bandwidth limited reconstruction of wave segments, is to realize a small form factor. Another problem is to provide a reasonable large volume for the user placement, which means to provide an acceptable freedom of movement. Both problems should be solved without decreasing the image quality of virtual and real object points, which are generated within the 3D display volume. A diffractive optical design using thick hologram gratings, which can be referred to as Bragg diffraction based volume gratings, can provide a small form factor and high definition natural viewing experience of 3D objects. A large collimated wave can be provided by an anamorphic backlight unit. The complex valued spatial light modulator add local curvatures to the wave field he is illuminated with. The modulated wave field is focused onto to the user plane by using a volume grating based field lens. Active type liquid crystal gratings provide 1D fine tracking of approximately ± 8° deg. Diffractive multiplex has to be implemented for each color and for a set of focus functions, which provide coarse tracking. Boundary conditions of the diffractive multiplexing are explained. This is done in regards to the display layout and by using the coupled wave theory (CWT). Aspects of diffractive cross talk and its suppression will be discussed including longitudinal apodized volume gratings. © 2016 SPIE.


Futterer G.,Deggendorf University of Applied Sciences
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2017

A Fizeau interferometer is significantly less sensitive to vibrations and air turbulence than other types of interferometers. This is due to the common path of the reference wave front and the object wave front. A common path arrangement offers the opportunity to reduce systematic errors of the measured phase of the surface under test (SUT). That is why Fizeau type interferometers are most commonly used to test e.g. plane surfaces, spheres or aspheres. A reduced uncertainty of the measured phase distribution can be obtained if the reference surface is placed close to the SUT. Multiple beam reflections will produce interference fringes, which are not sinusoidal. Furthermore, the discrete intensity distribution depends on the reflectance of the reference surface and the reflectance of the SUT. Some surfaces to be tested show significant variations of the local reflectance, e.g. lithographic masks with 0.05 ≤ r(x,y) ≤ 0.95. Thus, the inherent potential of phase shifting algorithms cannot be used. A modification of the reference surface can be applied. An on-Axis polarization beam splitter, which is placed in the plane of the reference surface, separates the two surfaces, which are imaged onto the detector. Thus, true two beam interference can be obtained. The potential of phase shifting algorithms can be used. The interference contrast is high, even if large local variations of r(x,y) are present. In addition, high speed operation is enabled. The embodiment of a modified Fizeau type interferometer will be described. © 2017 SPIE.


Trum C.J.,Deggendorf University of Applied Sciences | Sitzberger S.,Deggendorf University of Applied Sciences
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2017

The industrial production of components for applications in the area of precision optics has a long-standing tradition in Germany. As in almost all branches of industry, the external circumstances, processes and products have changed over time. Large lots are becoming less frequent and the demand for special components is growing. In order to meet these requirements, it is necessary to adapt the production processes quickly and flexibly. In the field of chemo-mechanical polishing (CMP), this means that in addition to the process parameters such as speed, pressure and feed, the task-specific adaptation of suspension and polishing pad carriers gain in importance. Along with these changes, it is becoming increasingly important to compare and evaluate the properties of the various polishing suspensions. The procedures according to DIN 58750-3 and DIN 58750-4 are suitable for this purpose. Due to the clearly defined procedures and the constant boundary conditions, different suspensions can be compared and evaluated. The study presented here shows that this method can also lead to misinterpretations. Known relationships, such as the influence of the polishing pad, the concentration of the suspension and the influence of the processed materials play an important role. An extension of the procedure of DIN 58750-3 for the test of a polishing agent can help in a task-specific characterization of polishing slurries. © 2017 SPIE.


Blobel B.,University of Regensburg | Blobel B.,Deggendorf University of Applied Sciences
Studies in Health Technology and Informatics | Year: 2017

Advanced health and social services paradigms are supported by a comprehensive set of domains managed by different scientific disciplines. Interoperability has to evolve beyond information and communication technology (ICT) concerns, including the real world business domains and their processes, but also the individual context of all actors involved. So, the system must properly reflect the environment in front and around the computer as essential and even defining part of the health system. This paper introduces an ICT-independent system-Theoretical, ontology-driven reference architecture model allowing the representation and harmonization of all domains involved including the transformation into an appropriate ICT design and implementation. The entire process is completely formalized and can therefore be fully automated. © 2017 European Federation for Medical Informatics (EFMI) and IOS Press.


Fallah Tehrani A.,Deggendorf University of Applied Sciences | Ahrens D.,Deggendorf University of Applied Sciences
Pattern Recognition Letters | Year: 2017

While an incorrect identification of underlying dependency in data can lead to a flawed conclusion, recognizing legitimate dependency allows for the opportunity to adapt a model in a correct manner. In this regard, modeling the inter-dependencies in multi-label classification (multi target prediction) is one of the challenging tasks from a machine learning point of view. While common approaches seek to exploit so-called correlated information from labels, this can be improved by assuming the interactions between labels. A well-known tool to model the interaction between attributes is the Choquet integral; it enables one to model non-linear dependencies between attributes. Beyond identifying proper prior knowledge in data (if such knowledge exists), establishing suitable models that are in agreement with prior knowledge is not always a trivial task. In this paper, we propose a first step towards modeling label dependencies for multi-target classifications in terms of positive and negative interactions. In the experimental, we demonstrate real gains by applying this approach. © 2017 Elsevier B.V.


Grant
Agency: European Commission | Branch: H2020 | Program: RIA | Phase: GV-8-2015 | Award Amount: 6.15M | Year: 2016

ELECTRIFIC will revolutionise how electric vehicles are integrated into power grid and users life. The fundamental premise on which the project will work that significant improvements to electromoblity can be unlocked by increasing coordination of all the actors in the electromobility ecosystem. To this end, the project will deliver novel techniques and ICT tools for enabling such coordination at all levels of the ecosystem. At the grid level, the project will develop new smart charging stations capable of dynamically controlling charging rate, maximizing the use of renewables and making as grid-friendly as possible. At level of EV users, the project will develop advanced driver assistance services that help and motivate the users plan travel and charging in a way that is convenient and yet respects potential constraints on charging capacity. Finally, at the EV fleet level, the project will develop management tools that help to optimise fleet operations, maximising battery lifetime and minimising charging costs. ELECTRIFIC comprises a balanced consortium of experienced research partners, energy providers and innovative electromobility SMEs. The results of the project will disseminated in the scientific community and rolled out to commercial use from e-bikes to e-buses, from private owners to government services and including cross-border mobility.


Fuchs E.,University of Passau | Gruber T.,Deggendorf University of Applied Sciences | Nitschke J.,University of Passau | Sick B.,Deggendorf University of Applied Sciences
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2010

The paper presents SwiftSeg, a novel technique for online time series segmentation and piecewise polynomial representation. The segmentation approach is based on a least-squares approximation of time series in sliding and/or growing time windows utilizing a basis of orthogonal polynomials. This allows the definition of fast update steps for the approximating polynomial, where the computational effort depends only on the degree of the approximating polynomial and not on the length of the time window. The coefficients of the orthogonal expansion of the approximating polynomialobtained by means of the update stepscan be interpreted as optimal (in the least-squares sense) estimators for average, slope, curvature, change of curvature, etc., of the signal in the time window considered. These coefficients, as well as the approximation error, may be used in a very intuitive way to define segmentation criteria. The properties of SwiftSeg are evaluated by means of some artificial and real benchmark time series. It is compared to three different offline and online techniques to assess its accuracy and runtime. It is shown that SwiftSegwhich is suitable for many data streaming applicationsoffers high accuracy at very low computational costs. © 2010 IEEE.


Reitmaier T.,University of Passau | Sick B.,Deggendorf University of Applied Sciences
IEEE SSCI 2011: Symposium Series on Computational Intelligence - CIDM 2011: 2011 IEEE Symposium on Computational Intelligence and Data Mining | Year: 2011

In this article, we introduce and investigate 3DS, a novel selection strategy for pool-based active training of a generative classifier, namely CMM (classifier based on a probabilistic mixture model). Such a generative classifier aims at modeling the processes underlying the generation of the data. The strategy 3DS considers the distance of samples to the decision boundary, the density in regions where samples are selected, and the diversity of samples in the query set that are chosen for labeling, e.g., by a human domain expert. The combination of the three measures in 3DS is adaptive in the sense that the weights of the distance and the density measure depend on the uniqueness of the classification. With nine benchmark data sets it is shown that 3DS outperforms a random selection strategy (baseline method), a pure closest sampling approach, ITDS (information theoretic diversity sampling), DWUS (density-weighted uncertainty sampling), DUAL (dual strategy for active learning), and PBAC (prototype based active learning) regarding evaluation criteria such as ranked performance based on classification accuracy, number of labeled samples (data utilization), and learning speed assessed by the area under the learning curve. © 2011 IEEE.


Futterer G.,Deggendorf University of Applied Sciences
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

An important chain link in modeling of three dimensional data (3D data), 3D prototyping, CAD-CAM, computerintegrated manufacturing (CIM), PC gaming, global 3D teleconferencing, future e-commerce, product advertisement and mobile infotainment is the visualization of 3D data and 3D objects. On the one hand, there is an increasing demand for 3D displays providing natural three dimensional viewing experience, but on the other hand there is a lack of available 3D displays capable of generating all depth cues. Available state of the art 3D displays can provide only a few depth cues and a very limited 3D experience. This is due to the inherent physical limits of the different approaches used. Holographic displays, for instance based on space bandwidth limited wave segment reconstruction, can provide all depth cues and a large viewing volume. They can provide satisfying 3D visualization. But still they are not available. Thick hologram gratings 1, which also can be referred to as Bragg diffraction based volume gratings, are key components, which enable small form factor holographic 3D displays. Manufacturing large, display size Bragg diffraction based volume gratings is challenging. Collimators are key components within interference lithographic exposure setups. Using off-axis parabolic mirrors (OAPM) as collimating optical elements enables the generation of exact plane waves by using a single reflective surface. Thus, off-axis parabolic mirrors are preferred in order to realize the collimation of large wave fronts. The surface roughness has to be very low. The relationship between holographic 3D displays and specific requirements, which have to be taken into account when manufacturing off-axis parabolic mirrors, will be presented. © 2016 SPIE.


Turnau M.,Deggendorf University of Applied Sciences
Transportation Research Part A: Policy and Practice | Year: 2015

In this study several hypotheses comprising a heuristic framework derived from rational-choice (RC) premises and regarding some potentially influencing variables on future use intention of different vehicle types are tested with a rural area sample. Especially the differentiation between long-term vs. short-term as well as functional/rational vs. extra-functional/emotional motivators is assessed. Results suggest a predominance of functional motivators and rational connotations over extra-functional/emotional ones. The models to check whether short-term or long-term effects dominate did not clearly confirm a predominance of long-term factors as hypothesized. In several regression models a moderating effect of rational short-term connotations on different long-term motivators was found, thus contributing notably to the prediction of future vehicle use-intention. The need for further research and theory-driven modeling is briefly discussed. © 2015 Elsevier Ltd.

Loading Deggendorf University of Applied Sciences collaborators
Loading Deggendorf University of Applied Sciences collaborators