@misc{HaugVernimReindl, author = {Haug, Sonja and Vernim, Matthias and Reindl, Andreas}, title = {Pr{\"a}sentation des Abschlussberichts "Integrationsbericht und Integrationskonzept f{\"u}r Regensburg"}, series = {Integrationsforum f{\"u}r Stadt und Landkreis Regensburg, 16.05.2014, Regensburg}, journal = {Integrationsforum f{\"u}r Stadt und Landkreis Regensburg, 16.05.2014, Regensburg}, language = {de} } @techreport{HaugVernimGelfertetal., author = {Haug, Sonja and Vernim, Matthias and Gelfert, Verena and Reindl, Andreas}, title = {Integrationsbericht und Integrationskonzept f{\"u}r Regensburg}, organization = {Stadt Regensburg und Ostbayerische Technische Hochschule Regensburg}, language = {de} } @article{ReindlZhengSchwarzetal., author = {Reindl, Klaus and Zheng, Yuanhang and Schwarz, Andreas and Meier, Stefan and Maas, Roland and Sehr, Armin and Kellermann, Walter}, title = {A stereophonic acoustic signal extraction scheme for noisy and reverberant environments}, series = {Computer Speech and Language}, volume = {27}, journal = {Computer Speech and Language}, number = {3}, publisher = {Elsevier}, doi = {10.1016/j.csl.2012.07.011}, pages = {726 -- 745}, abstract = {In this contribution, a novel two-channel acoustic front-end for robust automatic speech recognition in adverse acoustic environments with nonstationary interference and reverberation is proposed. From a MISO system perspective, a statistically optimum source signal extraction scheme based on the multichannel Wiener filter (MWF) is discussed for application in noisy and underdetermined scenarios. For free-field and diffuse noise conditions, this optimum scheme reduces to a Delay \& Sum beamformer followed by a single-channel Wiener postfilter. Scenarios with multiple simultaneously interfering sources and background noise are usually modeled by a diffuse noise field. However, in reality, the free-field assumption is very weak because of the reverberant nature of acoustic environments. Therefore, we propose to estimate this simplified MWF solution in each frequency bin separately to cope with reverberation. We show that this approach can very efficiently be realized by the combination of a blocking matrix based on semi-blind source separation ('directional BSS'), which provides a continuously updated reference of all undesired noise and interference components separated from the desired source and its reflections, and a single-channel Wiener postfilter. Moreover, it is shown, how the obtained reference signal of all undesired components can efficiently be used to realize the Wiener postfilter, and at the same time, generalizes well-known postfilter realizations. The proposed front-end and its integration into an automatic speech recognition (ASR) system are analyzed and evaluated in noisy living-room-like environments according to the PASCAL CHiME challenge. A comparison to a simplified front-end based on a free-field assumption shows that the introduced system substantially improves the speech quality and the recognition performance under the considered adverse conditions.}, language = {de} } @inproceedings{ReindlLangNiemetzetal., author = {Reindl, Andrea and Lang, Andreas and Niemetz, Michael and Meier, Hans}, title = {Switching and Averaging Models of a Bidirectional, Half-Bridge Based DC-DC converter with Load Distribution}, series = {Proceedings of the 15th International Modelica Conference 2023, Aachen, October 9-11}, booktitle = {Proceedings of the 15th International Modelica Conference 2023, Aachen, October 9-11}, publisher = {OJS}, doi = {10.3384/ecp204683}, abstract = {Batteries are used in numerous applications such as mobile devices, electric vehicles, home storage systems and islanded microgrids. Bidirectional DC-DC converters are vital for the integration of batteries, for the power conversion during (dis)charge and the battery management. Modeling of these is helpful, especially for the design of larger, more complex systems consisting of multiple DC-DC converters in parallel. Due to the high switching frequencies, the simulation of DC-DC converters is associated with increased computational time and effort. In this paper, three models of different complexity and accuracy are proposed for a bidirectional DC-DC converter consisting of two phase-shifted half-bridges. Two switching models, which differ mainly in the way the mosfets are driven, account for the individual switching operations and exhibit high accuracy. An averaging model replaces the switching elements with current and voltage sources providing the mean values. It is particularly suitable for multiple components and longer simulation durations. The dynamic behavior of the models is analyzed using the step responses of the load current. For validation, these are compared with the theoretical transfer function. The three models are analyzed comparatively in terms of computational time and effort. The calculation time of the averaging model has been reduced by two thirds compared to the strictly complementary switching model and by 96\% relative to the model with diode emulation mode. The averaging model requires only one third of the computation time of the complementary switching model and only 3.5\% of that of the model with diode emulation. Recommendations for the use of the models are given and a possible use case is shown. Two parallel connected DC-DC converters with load current sharing between them are simulated using the averaging model.}, language = {en} }