References of "2009"
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See detailJoint Bit Allocation and Precoding for MIMO Systems with Decision Feedback Detection
Bergman, Svante; Palomar, Daniel; Ottersten, Björn UL

in IEEE Transactions on Signal Processing (2009), 57(11), 4509-4521

This paper considers the joint design of bit loading, precoding and receive filters for a multiple-input multiple-output (MIMO) digital communication system employing decision feedback (DF) detection at ... [more ▼]

This paper considers the joint design of bit loading, precoding and receive filters for a multiple-input multiple-output (MIMO) digital communication system employing decision feedback (DF) detection at the receiver. Both the transmitter as well as the receiver are assumed to know the channel matrix perfectly. It is well known that, for linear MIMO transceivers, a diagonal transmission (i.e., orthogonalization of the channel matrix) is optimal for some criteria. Surprisingly, it was shown five years ago that for the family of Schur-convex functions an additional rotation of the symbols is necessary. However, if the bit loading is optimized jointly with the linear transceiver, then this rotation is unnecessary. Similarly, for DF MIMO optimized transceivers a rotation of the symbols is sometimes needed. The main result of this paper shows that for a DF MIMO transceiver where the bit loading is jointly optimized with the transceiver filters, the rotation of the symbols becomes unnecessary, and because of this, also the DF part of the receiver is not required. The proof is based on a relaxation of the available bit rates on the individual substreams to the set of positive real numbers. In practice, the signal constellations are discrete and the optimal relaxed bit loading has to be rounded. It is shown that the loss due to rounding is small, and an upper bound on the maximum loss is derived. Numerical results are presented that confirm the theoretical results and demonstrate that orthogonal transmission and the truly optimal DF design perform almost equally well. [less ▲]

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See detailGibt es einen Zusammenhang zwischen Schlafbezogenen Atemstörungen (SBAS) und Angstsensitivität?
Schröder, A.; Kemper, Christoph UL; Specht, M. et al

Poster (2009, November)

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See detailThe Causes and Mechanisms of Historical Dike Failures in the Netherlands
Van Baars, Stefan UL; Van Kempen, I.M.

in E-water (2009)

In a historical perspective, flood protection in the past was not given high priority - plague and periods of famine and war took precedence. Poverty and a lack of knowledge made it difficult to create ... [more ▼]

In a historical perspective, flood protection in the past was not given high priority - plague and periods of famine and war took precedence. Poverty and a lack of knowledge made it difficult to create safer dikes. Dike engineering did improve in Napoleonic era due to the French Central Government, but many dikes still failed. A historical overview of the causes and mechanisms of dike failures in the Netherlands has been drawn up, and resulted in a list of 337 recorded events leading to an assumed total of 1735 dike failures in the Netherlands between 1134 and 2006. Storm surges were, generally speaking, the primary cause of dike failure, followed by high water and ice drift. Two-thirds of all dikes failed as a result of the inner slope protection or the crest of the dike being eroded. The main causes for this were run-over and wave overflow, which could have been prevented, had the dikes been higher. The second cause of dike failure was ice drift. All other mechanisms were of minor importance, but were in the past either difficult to determine or even know about. [less ▲]

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See detailOn monopolistic competition and optimal product diversity: workers' rents also matter
Picard, Pierre M. UL; Toulemonde, Eric

in Canadian Journal of Economics (2009), 42(4), 1347-1360

In the Dixit-Stiglitz model of monopolistic competition, entry of rms is socially too small. Other authors have shown that excess entry is also a possibility with other preferences for diversity. We show ... [more ▼]

In the Dixit-Stiglitz model of monopolistic competition, entry of rms is socially too small. Other authors have shown that excess entry is also a possibility with other preferences for diversity. We show that workers rents also contribute to explain excess entry through a general equilibrium mechanism. Larger wages indeed raises the aggregate earnings and rms sales and pro ts, which entices too many rms to enter. We discuss the possibility of over-provision of varieties by comparing the equilibrium to unconstrained and constrained social optima and to other regulatory framework where wages are not controlled. [less ▲]

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See detailL'italiano, lingua del melodramma
Cicotti, Claudio UL

Speeches/Talks (2009)

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See detailWissenschaftliches Schreiben. Ein Praxisbuch für Studierende der Geistes- und Sozialwissenschaften
Gruber, Helmut; Huemer, Birgit UL; Rheindorf, Markus

Book published by Böhlau (2009)

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See detailLa stylistique : une discipline à l’aune de la vie
Freyermuth, Sylvie UL

Presentation (2009, October 27)

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See detailTraumberuf Landarzt - Berufliche Perspektiven des medizinischen Nachwuchses
Heinz, Andreas UL

Scientific Conference (2009, October 02)

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See detailWorking memory and language learning: A 4-year longitudinal study
Engel de Abreu, Pascale UL

Poster (2009, October)

The aim of the present study was to investigate the contribution of two working memory systems (the phonological loop and the central executive) to children’s foreign language learning. A sample of 119 ... [more ▼]

The aim of the present study was to investigate the contribution of two working memory systems (the phonological loop and the central executive) to children’s foreign language learning. A sample of 119 Luxembourgish children, whose native language is Luxembourgish and who learn German and French as secondary languages in school were assessed longitudinally over a 4-year time period. Children were tested in kindergarten (5 years of age), in first, second, and third grade with a one-year interval between each testing wave. Results indicate that individual differences in phonological loop functioning were causally related to foreign vocabulary development. One particular phonological loop measure - the repetition of low wordlike nonwords - was identified as the single best predictor of the acquisition of an unfamiliar foreign language up to two years later, suggesting that this measure may provide a valuable tool for early screening to identify children who are at present and future risk for foreign language learning difficulties. [less ▲]

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See detailInterdisciplinary cooperation on media effects
Steffgen, Georges UL

Presentation (2009, October)

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See detailIntroducing African literacies
Juffermans, Kasper UL; Asfaha, Yonas Mesfun; Kurvers, Jeanne

in van de Craats, Ineke; Kurvers, Jeanne (Eds.) Low-educated adult second language and literacy acquisition: Proceedings of the 4th symposium in Antwerp (2009)

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See detailAssociation between goal orientation and the means as well as the outcomes of a goal
Mustafic, Maida UL; Freund, Alexandra M.

Poster (2009, October)

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See detailHow to write if you cannot write: collaborative literacy in a Gambian village
Juffermans, Kasper UL

in van de Craats, Ineke; Kurvers, Jeanne (Eds.) Low-educated adult second language and literacy acquisition: Proceedings of the 4th symposium in Antwerp (2009)

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