@inproceedings{40768, abstract = {{We derive the generalized likelihood ratio test (GLRT) for detecting cyclostationarity in scalar-valued time series. The main idea behind our approach is Gladyshev’s relationship, which states that when the scalar-valued cyclostationary sig- nal is blocked at the known cycle period it produces a vector- valued wide-sense stationary process. This result amounts to saying that the covariance matrix of the vector obtained by stacking all observations of the time series is block-Toeplitz if the signal is cyclostationary, and Toeplitz if the signal is wide- sense stationary. The derivation of the GLRT requires the maximum likelihood estimates of Toeplitz and block-Toeplitz matrices. This can be managed asymptotically (for large num- berofsamples)exploitingSzego ̈’stheoremanditsgeneraliza- tion for vector-valued processes. Simulation results show the good performance of the proposed GLRT.}}, author = {{Ramírez, D. and Scharf, L. L. and Vía, J. and Santamaría, I. and Schreier, P. J.}}, booktitle = {{Proc.\ IEEE Int.\ Conf.\ Acoustics, Speech and Signal Process.}}, title = {{{An asymptotic GLRT for the detection of cyclostationary signals}}}, doi = {{10.1109/ICASSP.2014.6854234}}, year = {{2014}}, } @article{38094, author = {{Harder, G. and Mogilevtsev, D. and Korolkova, N. and Silberhorn, Christine}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, keywords = {{General Physics and Astronomy}}, number = {{7}}, publisher = {{American Physical Society (APS)}}, title = {{{Tomography by Noise}}}, doi = {{10.1103/physrevlett.113.070403}}, volume = {{113}}, year = {{2014}}, } @inbook{37922, author = {{Grotjahn, Rebecca}}, booktitle = {{Blickpunkt Bühne. Musiktheater in Deutschland von 1900 bis 1950}}, editor = {{Steiert , Thomas and Coul, Paul Op de }}, isbn = {{978-3-936655-35-3}}, publisher = {{Dohr}}, title = {{{Stimmbesitzer und Sängerdarsteller. Die Inszenierung des Singens auf der Musiktheater-Bühne in den ersten Jahrzehnten des 20. Jahrhunderts}}}, year = {{2014}}, } @article{40757, abstract = {{In this paper, we propose a novel mechanism for spectrum sensing that leads us to exploit the spatio-temporal correlation present in the received signal at a multi-antenna receiver. For the proposed mechanism, we formulate the spectrum sensing scheme by adopting the generalized likelihood ratio test (GLRT). However, the GLRT degenerates in the case of limited sample support. To circumvent this problem, several extensions are proposed that bring robustness to the GLRT in the case of high dimensionality and small sample size. In order to achieve these sample-efficient detection schemes, we modify the GLRT-based detector by exploiting the covariance structure and factoring the large spatio-temporal covariance matrix into spatial and temporal covariance matrices. The performance of the proposed detectors is evaluated by means of numerical simulations, showing important advantages over existing detectors.}}, author = {{Ali, S. and Ramírez, D. and Jansson, M. and Seco-Granados, G. and López-Salcedo, J. A.}}, journal = {{Eurasip\ J.\ Applied Signal Process.}}, title = {{{Multi-antenna spectrum sensing by exploiting spatio-temporal correlation}}}, doi = {{10.1186/1687-6180-2014-160}}, volume = {{160}}, year = {{2014}}, } @article{40758, abstract = {{Phase synchronization among neuronal oscillations within the same frequency band has been hypothesized to be a major mechanism for communication between different brain areas. On the other hand, cross-frequency com- munications are more flexible allowing interactions between oscillations with different frequencies. Among such cross-frequency interactions amplitude-to-amplitude interactions are of a special interest as they show how the strength of spatial synchronization in different neuronal populations relates to each other during a given task. While, previously, amplitude-to-amplitude correlations were studied primarily on the sensor level, we present a source separation approach using spatial filters which maximize the correlation between the envelopes of brain oscillations recorded with electro-/magnetoencephalography (EEG/MEG) or intracranial multichannel re- cordings. Our approach, which is called canonical source power correlation analysis (cSPoC), is thereby capable of extracting genuine brain oscillations solely based on their assumed coupling behavior even when the signal-to- noise ratio of the signals is low. In addition to using cSPoC for the analysis of cross-frequency interactions in the same subject, we show that it can also be utilized for studying amplitude dynamics of neuronal oscillations across subjects. We assess the performance of cSPoC in simulations as well as in three distinctively different analysis sce- narios of real EEG data, each involving several subjects. In the simulations, cSPoC outperforms unsupervised state-of-the-art approaches. In the analysis of real EEG recordings, we demonstrate excellent unsupervised dis- covery of meaningful power-to-power couplings, within as well as across subjects and frequency bands.}}, author = {{Dähne, S. and Nikulin, V. V. and Ramírez, D. and Schreier, P. J. and Müller, K.-R. and Haufe, S.}}, journal = {{NeuroImage}}, pages = {{334–348}}, title = {{{Finding brain oscillations with power dependencies in neuroimaging data}}}, doi = {{10.1016/j.neuroimage.2014.03.075}}, volume = {{96}}, year = {{2014}}, } @article{40762, abstract = {{Detecting and analyzing directional structures in images is important in many applications since one-dimensional patterns often correspond to important features such as object contours or trajectories. Classifying a structure as directional or non-directional requires a measure to quantify the degree of directionality and a threshold, which needs to be chosen based on the statistics of the image. In order to do this, we model the image as a random field. So far, little research has been performed on analyzing directionality in random fields. In this paper, we propose a measure to quantify the degree of directionality based on the random monogenic signal, which enables a unique decomposition of a 2D signal into local amplitude, local orientation, and local phase. We investigate the second-order statistical properties of the monogenic signal for isotropic, anisotropic, and unidirectional random fields. We analyze our measure of directionality for finite-size sample images, and determine a threshold to distinguish between unidirectional and non-unidirectional random fields, which allows the automatic classification of images.}}, author = {{Olhede, S. C. and Ramírez, D. and Schreier, P. J.}}, journal = {{IEEE Trans.\ Inform.\ Theory}}, number = {{10}}, pages = {{6491–6510}}, title = {{{Detecting Directionality in Random Fields Using the Monogenic Signal}}}, doi = {{10.1109/TIT.2014.2342734}}, volume = {{60}}, year = {{2014}}, } @inproceedings{40759, abstract = {{We derive an estimator of the cycle period of a univariate cyclostationary process based on an information- theoretic criterion. Transforming the univariate cyclostationary process into a vector-valued wide-sense stationary process allows us to obtain the structure of the covariance matrix, which is block-Toeplitz, and its block size depends on the unknown cycle period. Therefore, we sweep the block size and obtain the ML estimate of the covariance matrix, required for the information- theoretic criterion. Since there are no closed-form ML estimates of block-Toeplitz matrices, we asymptotically approximate them as block-circulant. Finally, some numerical examples show the good performance of the proposed estimator.}}, author = {{Ramírez, D. and Schreier, P. J. and Vía, J. and Santamaría, I. and Scharf, L. L.}}, booktitle = {{Proc.\ Asilomar Conf.\ Signals Syst.\ Computers}}, title = {{{A Regularized Maximum Likelihood Estimator for the Period of a Cyclostationary Process}}}, year = {{2014}}, } @article{38105, author = {{Motka, L. and Stoklasa, B. and Rehacek, J. and Hradil, Z. and Karasek, V. and Mogilevtsev, D. and Harder, G. and Silberhorn, Christine and Sánchez-Soto, L. L.}}, issn = {{1050-2947}}, journal = {{Physical Review A}}, keywords = {{Atomic and Molecular Physics, and Optics}}, number = {{5}}, publisher = {{American Physical Society (APS)}}, title = {{{Efficient algorithm for optimizing data-pattern tomography}}}, doi = {{10.1103/physreva.89.054102}}, volume = {{89}}, year = {{2014}}, } @inproceedings{42025, author = {{Bulgarini, G and Reimer, M.E and Bavinck, M. Bouwes and Jöns, Klaus D. and Dalacu, D and Poole, P.J and Bakkers, E.P.A.M and Zwiller, V}}, number = {{7}}, pages = {{4102--4106}}, title = {{{Nanowire waveguides launching single photons in a Gaussian mode for ideal fiber-coupling}}}, volume = {{14}}, year = {{2014}}, } @inproceedings{42024, author = {{ Versteegh, M.A.M and Reimer, M.E and Jöns, Klaus D. and Dalacu, D and Poole, P.J and Gulinatti, A and Giudice, A and Zwiller, V}}, title = {{{Observation of strongly entangled photon pairs from a nanowire quantum dot}}}, volume = {{5}}, year = {{2014}}, } @inproceedings{42026, author = {{Müller, M and Bounouar, S and Jöns, Klaus D. and Glässl, M and Michler, P}}, pages = {{224--228}}, title = {{{On-demand generation of indistinguishable polarization-entangled photon pairs}}}, volume = {{8}}, year = {{2014}}, } @inbook{25950, abstract = {{In this paper, the development and validation of a shield prototype for resistive sensor array characterization with Arduino UNO, a platform based on ATmega328 microcontroller provided by ATMEL, is reported. The resistance variation of the sensor can be evaluated by properly choosing the capacitance value and by measuring the period (frequency) of a custom inverter-based oscillator. The GUI and the developed firmware are able to perform the real-time monitoring of the sensor responses. The developed shield is able to measure the response of up to six sensors under UV radiation by means of LED devices. First results carried out with resistive sensors based on mesoporous In2O3-based material under UV light exposure are reported.}}, author = {{Aloisio, D. and Donato, N. and Neri, G. and Latino, M. and Wagner, T. and Tiemann, Michael and Capra, P. P.}}, booktitle = {{Lecture Notes in Electrical Engineering}}, issn = {{1876-1100}}, title = {{{Arduino-Based Shield for Resistive Gas Sensor Array Characterization Under UV Light Exposure}}}, doi = {{10.1007/978-3-319-00684-0_79}}, year = {{2014}}, } @article{43908, author = {{Schroeter-Wittke, Harald}}, journal = {{Praktische Theologie}}, pages = {{259--260}}, title = {{{Impuls und Design - Friedensklänge aus dem 20. Jahrhundert. Zum 100. Geburtstag von Andrzej Panufnik}}}, volume = {{49}}, year = {{2014}}, } @inproceedings{43920, abstract = {{Dynamical Bloch oscillations and coherent interband polarization in bulk GaSe are controlled by CEP-stable, ultra-intense multi-THz waveforms and result in the emission of phase-stable high-order harmonics covering 12.7 optical octaves from THz to VIS regimes.}}, author = {{Meier, Torsten and Langer, F. and Schubert, O. and Hohenleutner, M. and Urbanek, B. and Lange, C. and Huttner, U. and Golde, D. and Kira, M. and Koch, S.W. and Huber, R.}}, booktitle = {{CLEO: QELS_Fundamental Science}}, isbn = {{978-1-55752-999-2}}, location = {{San Jose, California United States}}, title = {{{CEP control of dynamical Bloch oscillations in a bulk semiconductor via ultra-intense multi-THz fields}}}, doi = {{10.1364/CLEO_QELS.2014.FTh1C.1}}, year = {{2014}}, } @article{22957, abstract = {{We show, by means of numerical and analytical methods, that media with a repulsive nonlinearity which grows from the center to the periphery support a remarkable variety of previously unknown complex stationary and dynamical three-dimensional (3D) solitary-wave states. Peanut-shaped modulation profiles give rise to vertically symmetric and antisymmetric vortex states, and novel stationary hybrid states, built of top and bottom vortices with opposite topological charges, as well as robust dynamical hybrids, which feature stable precession of a vortex on top of a zero-vorticity soliton. The analysis reveals stability regions for symmetric, antisymmetric, and hybrid states. In addition, bead-shaped modulation profiles give rise to the first example of exact analytical solutions for stable 3D vortex solitons. The predicted states may be realized in media with a controllable cubic nonlinearity, such as Bose–Einstein condensates.}}, author = {{Driben, Rodislav and Kartashov, Yaroslav V. and Malomed, Boris A. and Meier, Torsten and Torner, Lluis}}, issn = {{1367-2630}}, journal = {{New Journal of Physics}}, title = {{{Three-dimensional hybrid vortex solitons}}}, doi = {{10.1088/1367-2630/16/6/063035}}, volume = {{16}}, year = {{2014}}, } @inproceedings{39497, abstract = {{The wide usage of thermoelectric generators (TEG) is still blocked by very high product costs. This paper presents anodized aluminum (Al) as an effective and cheap alternative for ceramics like alumina (Al2O3) or aluminum nitride (AlN). Al has a significantly higher thermal conductivity as both named ceramics. In addition, the lower thermal stability of Al is still high enough to work with bismuth telluride based modules, which are most common. To show the advantages of the changed substrate, finite element method (FEM) simulations were performed. These simulations show that by changing the cold side substrate material the temperature drop across the substrate is reduced by 60 K. This correlates to a theoretical power gain of more than 20 {%}. Furthermore, Al can be shaped much easier than a ceramic material. The biggest advantage is obviously the price. Anodized Al is around twenty times cheaper than Al2O3. To demonstrate the easy fabrication of the proposed substrate, samples were prepared only with widely used processes like those used for conventional printed circuit boards.}}, author = {{Assion, F. and Geneiß, V. and Schönhoff, M. and Hedayat, C. and Hilleringmann, Ulrich}}, booktitle = {{Proceedings of the 11th European Conference on Thermoelectrics}}, editor = {{Amaldi, Andrea and Tang, Francois}}, isbn = {{978-3-319-07332-3}}, pages = {{83–88}}, publisher = {{Springer International Publishing}}, title = {{{Anodized Aluminum as Effective and Cheap Alternative Substrate for Thermoelectric Generators}}}, year = {{2014}}, } @inproceedings{39494, author = {{Kanwar, Kelash and Mager, Thomas and Hilleringmann, Ulrich and Geneiss, Volker and Hedayat, Christian}}, booktitle = {{2014 IEEE RFID Technology and Applications Conference (RFID-TA)}}, publisher = {{IEEE}}, title = {{{Embedded UHF RFID tag design process for rubber transmission belt using 3D model}}}, doi = {{10.1109/rfid-ta.2014.6934208}}, year = {{2014}}, } @inproceedings{43914, abstract = {{Ultra-intense and CEP-stable waveforms in the multi-THz range control dynamical Bloch oscillations and interband polarization in bulk GaSe, leading to the emission of all-coherent high-order harmonics covering 12.7 optical octaves from THz to VIS regimes.}}, author = {{Meier, Torsten and Hohenleutner, M. and Schubert, O. and Langer, F. and Urbanek, B. and Lange, C. and Huttner, U. and Golde, D. and Kira, M. and Koch, S.W. and Huber, R.}}, booktitle = {{19th International Conference on Ultrafast Phenomena}}, isbn = {{1-55752-279-0}}, location = {{Okinawa Japan}}, title = {{{Phase-locked multi-THz high-harmonic generation by dynamical bloch oscillations in bulk semiconductors}}}, doi = {{10.1364/UP.2014.10.Thu.A.3}}, year = {{2014}}, } @article{22955, abstract = {{The dynamics of 3D Airy-vortex wave packets is studied under the action of strong self-focusing Kerr nonlinearity. Emissions of nonlinear 3D waves out of the main wave packets with the topological charges were demonstrated. Because of the conservation of the total angular momentum, charges of the emitted waves are equal to those carried by the parental light structure. The rapid collapse imposes a severe limitation on the propagation of multidimensional waves in Kerr media. However, the structure of the Airy beam carrier allows the coupling of light from the leading, most intense peak into neighboring peaks and consequently strongly postpones the collapse. The dependence of the critical input amplitude for the appearance of a fast collapse on the beam width is studied for wave packets with zero and nonzero topological charges. Wave packets carrying angular momentum are found to be much more resistant to the rapid collapse.}}, author = {{Driben, Rodislav and Meier, Torsten}}, issn = {{0146-9592}}, journal = {{Optics Letters}}, number = {{19}}, pages = {{5539--5542}}, title = {{{Nonlinear dynamics of Airy-vortex 3D wave packets: emission of vortex light waves}}}, doi = {{10.1364/ol.39.005539}}, volume = {{39}}, year = {{2014}}, } @inbook{44746, author = {{Herzig, Bardo and Aßmann, S.}}, booktitle = {{School’s out? Informelle und formelle Medienbildung}}, editor = {{Aßmann, S. and Meister, D. M. and Pielsticker, A.}}, pages = {{43--55}}, publisher = {{kopaed}}, title = {{{Entgrenzung von Schule in der digitalen Welt}}}, year = {{2014}}, }