@inproceedings{39360, author = {{Krupp, Alexander and Müller, Wolfgang}}, title = {{{Formale Verfeinerung und Modelchecking von zeitbehafteten endlichen Automaten}}}, year = {{2003}}, } @inproceedings{39368, author = {{Krupp, Alexander and Müller, Wolfgang}}, booktitle = {{Proceedings of FDL'03}}, title = {{{Combining Formal Refinement and Model Checking for Analysis of Realtime Systems}}}, year = {{2003}}, } @inproceedings{39369, abstract = {{The latest OCL 2.0 proposal provides two semantic descriptions, i.e., a metamodel based semantics that uses UML itself to associate the semantic domain with the language concepts and a formal semantics based on a set-theoretic approach called object model. Unfortunately, these two semantics are currently neither consistent nor complete, as (a) the formal semantics does not consider the newly introduced concept of OCL messages and (b) both semantics lack an integration of Statecharts and a semantic denition of state-related operations. This article focuses on a formal semantics for OCL messages as a foundation for consistency among,the two OCL semantics. We extend object models and present an extended denition of a system state that comprises all relevant information to be able to evaluate OCL expressions also w.r.t. OCL messages.}}, author = {{Flake, Stephan and Müller, Wolfgang}}, booktitle = {{Proceedings of the Workshop OCL 2.0 at UML 2003}}, title = {{{Formal Semantics of OCL Messages}}}, year = {{2003}}, } @article{38422, author = {{Milivojevic, B and Sandel, D and Bhandare, S and Noé, Reinhold and Wust, F}}, issn = {{0013-5194}}, journal = {{ELECTRONICS LETTERS}}, number = {{20}}, pages = {{1455--1456}}, title = {{{40 Gbit/s CSRZ-DPSK transmission system with signed online chromatic dispersion detection}}}, doi = {{10.1049/el:20030933}}, volume = {{39}}, year = {{2003}}, } @article{38388, author = {{Sandel, D and Mirvocla, V and Wust, F and Noé, Reinhold}}, issn = {{0948-7921}}, journal = {{ELECTRICAL ENGINEERING}}, number = {{1}}, pages = {{41--44}}, title = {{{Robust, signed, online chromatic dispersion detection in a 40-Gbit/s optical transmission link}}}, doi = {{10.1007/S00202-002-0138-2}}, volume = {{85}}, year = {{2003}}, } @article{38375, author = {{Bhandare, S and Sandel, D and Noé, Reinhold and Ricken, R and Suche, H and Sohler, W}}, issn = {{1350-2409}}, journal = {{IEE PROCEEDINGS-CIRCUITS DEVICES AND SYSTEMS}}, number = {{6}}, pages = {{490--494}}, title = {{{LiNbO3-based integrated optical network analyser for vectorial structure characterisation of fibre Bragg gratings}}}, doi = {{10.1049/ip-cds:20030762}}, volume = {{150}}, year = {{2003}}, } @article{38358, author = {{Sandel, D and Mirvoda, V and Bhandare, S and Wust, F and Noé, Reinhold}}, issn = {{0733-8724}}, journal = {{JOURNAL OF LIGHTWAVE TECHNOLOGY}}, number = {{5}}, pages = {{1198--1210}}, title = {{{Some enabling techniques for polarization mode dispersion compensation}}}, doi = {{10.1109/JLT.2003.811563}}, volume = {{21}}, year = {{2003}}, } @article{38325, author = {{Bhandare, S and Sandel, D and Noé, Reinhold and Ricken, R and Suche, H and Sohler, W}}, issn = {{1350-2409}}, journal = {{IEE PROCEEDINGS-CIRCUITS DEVICES AND SYSTEMS}}, number = {{6}}, pages = {{490--494}}, title = {{{LiNbO3-based integrated optical network analyser for vectorial structure characterisation of fibre Bragg gratings}}}, doi = {{10.1049/ip-cds:20030762}}, volume = {{150}}, year = {{2003}}, } @article{38308, author = {{Sandel, D and Mirvoda, V and Bhandare, S and Wust, F and Noé, Reinhold}}, issn = {{0733-8724}}, journal = {{JOURNAL OF LIGHTWAVE TECHNOLOGY}}, number = {{5}}, pages = {{1198--1210}}, title = {{{Some enabling techniques for polarization mode dispersion compensation}}}, doi = {{10.1109/JLT.2003.811563}}, volume = {{21}}, year = {{2003}}, } @inbook{39956, author = {{Rösler, Margit}}, booktitle = {{Lecture Notes in Mathematics}}, isbn = {{9783540403753}}, issn = {{0075-8434}}, pages = {{93–135}}, publisher = {{Springer Berlin Heidelberg}}, title = {{{Dunkl Operators: Theory and Applications}}}, doi = {{10.1007/3-540-44945-0_3}}, year = {{2003}}, } @inproceedings{40903, abstract = {{Non-stationary complex random signals are in general improper (not circularly symmetric), which means that their complementary covariance is non-zero. Since the Karhunen-Loeve expansion in its known form is only valid for proper processes, we derive the improper version of this expansion. It produces two sets of eigenvalues and an improper internal description. We use the Karhunen-Loeve expansion to solve the problem of detecting non-stationary improper complex random signals in additive white Gaussian noise. Using the deflection criterion we compare the performance of conventional processing, which ignores complementary covariances, with processing that takes these into account. The performance gain can be as great as a factor of 2.}}, author = {{Schreier, Peter J. and Scharf, Louis L.}}, booktitle = {{Proc.\ IEEE Int.\ Conf.\ Acoustics, Speech and Signal Process.}}, pages = {{717–720}}, title = {{{The Karhunen-Loève expansion of improper complex random signals with applications in detection}}}, doi = {{10.1109/ICASSP.2003.1201782}}, volume = {{6}}, year = {{2003}}, } @inproceedings{40900, abstract = {{In this paper we describe a beamforming algorithm based on widely-linear rather than linear data models. Initially, we develop this beamformer by generalizing the Capon (MVDR) optimization problem. That is, if the objective is to minimize output power while maintaining a specified directional gain, then we show that the output power of the widely-linear beamformer is less than or equal to the output power of the Capon (MVDR) beamformer. This result is valid regardless of the “true” distribution of the data. We also derive the widely-linear beamformer by considering beamforming to be an estimation problem. Linear models assume that the composite covariance matrix formed from the real and imaginary parts of the array-snapshot has a particular structure. This structure is often summarized by stating that the covariance formed from the array snapshot and its transpose (not Hermitian transpose) is zero. We could also call these data “proper” Gaussian vectors. The beamformers in this paper are appropriate for situations in which these implicit assumptions are violated.}}, author = {{McWhorter, Todd and Schreier, Peter J.}}, booktitle = {{Proc. 37th\ Asilomar Conf.\ Signals Syst.\ Computers}}, pages = {{753–759}}, title = {{{Widely-linear beamforming}}}, doi = {{10.1109/ACSSC.2003.1292015}}, volume = {{1}}, year = {{2003}}, } @inproceedings{40901, abstract = {{Historically, transform coding of noisy sources has been performed by first estimating the message and then quantizing this estimate. We show that it is also optimum to first transform the noisy observations into canonical coordinates, quantize, apply a Wiener filter in this coordinate system, and then transform the result back to the original coordinates. Canonical coordinates are uncorrelated, and quantizing and Wiener filtering are applied to each component independently. Optimality of this approach can be proved assuming additive white quantization noise. Half canonical coordinates minimize the mean-squared error by minimizing the trace of the error covariance matrix and full canonical coordinates maximize information rate by minimizing the determinant of the error covariance matrix.}}, author = {{Schreier, Peter J. and Scharf, Louis L. and Hu, Tianjian and Voran, Stephen D.}}, booktitle = {{Proc.\ IEEE Works.\ Statistical Signal Proces.}}, pages = {{234–237}}, title = {{{Canonical coordinates are the right coordinate system for transform coding of noisy sources}}}, doi = {{10.1109/SSP.2003.1289387}}, year = {{2003}}, } @inproceedings{40902, abstract = {{Recently, a number of papers have been published that show significant performance gains can be obtained by accounting for the fact that communication signals can be improper. In this paper, we derive a general result comparing the performance of conventional processing, which ignores the improper nature of signals, with processing that takes it into account. In particular, for an estimation and a detection problem, we find that the performance gain, as measured by mean-squared error and deflection, respectively, can be as large as a factor of 2, but no larger. In a communications example, we show how this finding generalizes the result that coherent processing enjoys a 3 dB gain over non-coherent processing.}}, author = {{Schreier, Peter J. and Scharf, Louis L. and Mullis, Clifford T.}}, booktitle = {{Proc.\ IEEE Works.\ Statistical Signal Proces.}}, pages = {{114–117}}, title = {{{A unified approach to performance comparisons between linear and widely linear processing}}}, doi = {{10.1109/SSP.2003.1289353}}, year = {{2003}}, } @article{40899, abstract = {{We challenge the perception that we live in a “proper world”, where complex random signals can always be assumed to be proper (also called circularly symmetric). Rather, we stress the fact that the analytic signal constructed from a nonstationary real signal is, in general, improper, which means that its complementary correlation function is nonzero. We explore the consequences of this finding in the context of stochastic time-frequency analysis in Cohen’s class. There, the analytic signal plays a prominent role because it reduces interference terms. However, the usual time-frequency representation (TFR) based on the analytic signal gives only an incomplete signal description. It must be augmented by a complementary TFR whose properties we develop in detail. We show why it is still advantageous to use the pair of standard and complementary TFRs of the analytic signal rather than the TFR of the corresponding real signal.}}, author = {{Schreier, Peter J. and Scharf, Louis L.}}, journal = {{{IEEE} {T}rans.\ {S}ignal\ {P}rocess.}}, number = {{12}}, pages = {{3071–3079}}, title = {{{Stochastic time-frequency analysis using the analytic signal: why the complementary distribution matters}}}, doi = {{10.1109/TSP.2003.818911}}, volume = {{51}}, year = {{2003}}, } @article{39957, abstract = {{It is an open conjecture that generalized Bessel functions associated with root systems have a positive product formula for non-negative multiplicity parameters of the associated Dunkl operators. In this paper, a partial result towards this conjecture is proven, namely a positive radial product formula for the non-symmetric counterpart of the generalized Bessel function, the Dunkl kernel. Radial hereby means that one of the factors in the product formula is replaced by its mean over a sphere. The key to this product formula is a positivity result for the Dunkl-type spherical mean operator. It can also be interpreted in the sense that the Dunkl-type generalized translation of radial functions is positivity-preserving. As an application, we construct Dunkl-type homogeneous Markov processes associated with radial probability distributions.}}, author = {{Rösler, Margit}}, journal = {{Transactions of the American Mathematical Society}}, number = {{6}}, pages = {{2413–2438}}, publisher = {{American Mathematical Society (AMS)}}, title = {{{A positive radial product formula for the Dunkl kernel}}}, doi = {{10.48550/ARXIV.MATH/0210137}}, volume = {{355}}, year = {{2003}}, } @article{40904, abstract = {{We present a comprehensive treatment of the second-order theory of complex random vectors and wide-sense stationary (WSS) signals. The main focus is on the improper case, in which the complementary covariance does not vanish. Accounting for the information present in the complementary covariance requires the use of widely linear transformations. Based on these, we present the eigenanalysis of complex vectors and apply it to the problem of rank reduction through principal components. We also investigate joint properties of two complex vectors by introducing canonical correlations, which paves the way for a discussion of the Wiener filter and its rank-reduced version. We link the concepts of propriety and joint propriety to eigenanalysis and canonical correlation analysis, respectively. Our treatment is extended to WSS signals. In particular, we give a result on the asymptotic distribution of eigenvalues and examine the connection between WSS, proper, and analytic signals.}}, author = {{Schreier, Peter J. and Scharf, Louis L.}}, journal = {{{IEEE} {T}rans.\ {S}ignal\ {P}rocess.}}, number = {{3}}, pages = {{714–725}}, title = {{{Second-order analysis of improper complex random vectors and processes}}}, doi = {{10.1109/TSP.2002.808085}}, volume = {{51}}, year = {{2003}}, } @article{34896, abstract = {{We apply class field theory to the computation of the minimal discriminants for certain solvable groups. In particular, we apply our techniques to small Frobenius groups and all imprimitive degree 8 groups such that the corresponding fields have only a degree 2 and no degree 4 subfield.}}, author = {{Fieker, Claus and Klüners, Jürgen}}, issn = {{0022-314X}}, journal = {{Journal of Number Theory}}, keywords = {{Algebra and Number Theory}}, number = {{2}}, pages = {{318--337}}, publisher = {{Elsevier BV}}, title = {{{Minimal discriminants for fields with small Frobenius groups as Galois groups}}}, doi = {{10.1016/s0022-314x(02)00071-9}}, volume = {{99}}, year = {{2003}}, } @inproceedings{39887, author = {{Hilleringmann, Ulrich and Vieregge, T. and Horstmann, J.T.}}, booktitle = {{IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)}}, publisher = {{IEEE}}, title = {{{Masking and etching of silicon and related materials for geometries down to 25 nm}}}, doi = {{10.1109/iecon.1999.822171}}, year = {{2003}}, } @inproceedings{39888, author = {{Horstmann, J.T. and Hilleringmann, Ulrich and Goser, K.}}, booktitle = {{IECON'99. Conference Proceedings. 25th Annual Conference of the IEEE Industrial Electronics Society (Cat. No.99CH37029)}}, publisher = {{IEEE}}, title = {{{Matching analysis of NMOS-transistors with a channel length down to 30 nm}}}, doi = {{10.1109/iecon.1999.822163}}, year = {{2003}}, }