Reduced feedback SDMA based on subspace packings

in IEEE Transactions on Wireless Communications (2009), 8(3), 13291339

Herein, we treat Space Division Multiple Access (SDMA) based on partial channel state information and limited feedback. We propose a novel framework utilizing subspace packings, where beamforming ... [more ▼]

Herein, we treat Space Division Multiple Access (SDMA) based on partial channel state information and limited feedback. We propose a novel framework utilizing subspace packings, where beamforming, feedback, and scheduling are integrated. Advantages of the proposed framework are that the fed back supportable rates are based on the post-scheduling SINR and that the feedback implicitly contains information about the spatial compatibility of the users. The feasibility region of packings of different dimensions is indicated by the allocation outage probability which is derived. Grassmannian subspace packings, DFT-based packings, and non-orthogonal Grassmannian packings are formulated and studied as candidates. Numerical simulations show better performance for the proposed scheme compared to conventional channel quantization at the receiver with zero-forcing transmission in i.i.d. Rayleigh fading. Finally, we propose and evaluate a beam-graph method to further reduce the feedback load, that can be used in the context of tracking quantized beamformers. [less ▲]

Urteilsfehler in der schulischen Leistungsbeurteilung: Der Einfluss von Verarbeitungszielen und Expertise

Scientific Conference (2009, March)

Wohlstand jenseits des Einkommens. Der „Capabilities“-Ansatz in Bildungs- und Gesundheitswesen bewertet Teilhabe an der Gesellschaft

Article for general public (2009)

Würde sich der Wohlstand einer Gesellschaft am Bruttoinlandsprodukt pro Kopf bemessen, hätte das Emirat Katar international die Nase vorn, gefolgt von Luxemburg und Norwegen. Rang vier würde das Sultanat ... [more ▼]

Würde sich der Wohlstand einer Gesellschaft am Bruttoinlandsprodukt pro Kopf bemessen, hätte das Emirat Katar international die Nase vorn, gefolgt von Luxemburg und Norwegen. Rang vier würde das Sultanat Brunei auf der Insel Borneo belegen, wo seit 1988 Parteien verboten sind und der Sultan per Dekret regiert. Ganz so einfach sollte man es sich mit der Wohlstandsmessung nicht machen. Um den Reichtum einer Gesellschaft vergleichend zu beurteilen, bedarf es weiterer Kriterien. Die Suche nach dem guten Leben beschäftigt Philosophen seit Platon und Aristoteles. Auch heute mangelt es unter Sozialwissenschaftlern nicht an Theorien der Gerechtigkeit. Der Ökonomie-Nobelpreisträger Amartya Sen und die Rechtsphilosophin und diesjährige A.SK-Preisträgerin Martha Nussbaum haben einen ganz eigenen Maßstab entwickelt, um den Zustand eines Gemeinwesens zu prüfen - weit über ökonomische Kennzahlen hinaus. Kann ein Mensch ein Leben führen, für das er sich aus guten Gründen entschieden hat und das seine Selbstachtung garantiert, fragen sie. Kann er sich bilden, arbeiten und politisch engagieren? Hat er Zugang zum Gesundheitssystem? Steht ihm angemessener Wohnraum zu Verfügung? Verwirklichungschancen (capabilities) haben Sen und Nussbaum ihren Ansatz genannt. Dahinter steckt eine zweifache Annahme: Der Einzelne ist seines Glückes Schmied, aber sein Leben gelingt nur in dem Maße, wie die Gesellschaft ihn dabei unterstützt. [less ▲]

Analyse de fiabilité des systèmes semicohérents et description par des polynômes latticiels

Scientific Conference (2009, February 10)

Inside the Serbian war machine: The Milošević intercepts, 1991-1992

in East European Politics & Societies (2009), 23(1), 86-104

This article examines the arguably most interesting pieces of evidence used during the trial of Slobodan Milošević at the International Criminal Tribunal for the former Yugoslavia—more than two hundred ... [more ▼]

This article examines the arguably most interesting pieces of evidence used during the trial of Slobodan Milošević at the International Criminal Tribunal for the former Yugoslavia—more than two hundred recordings of intercepted conversations that took place in 1991 and 1992 between Milošević, Radovan Karadžić, Dobrica Ćosić, and various other protagonists on the Serbian side of the wars in Croatia and Bosnia and Herzegovina (BiH). Analysis of the intercepts presented in this article makes several important contributions to the interpretation of events in former Yugoslavia during that period. First, it identifies the ideological foundations of Milošević-led Serbian war campaigns in the political influence of Dobrica Ćosić and his platform of “unification of Serbs.” Second, it contributes to the vigorous debate regarding the possible deal between Milošević and the Croatian president Franjo Tuđman for the division of BiH. It confirms that negotiations took place, but that Milošević and his associates had no intention of respecting any agreement and wanted the whole of BiH until at least late 1991. Third, it provides indications that Milošević held the position of the de facto commander-in-chief in the operations of the Yugoslav People's Army in Croatia and BiH. And fourth, it establishes that the two institutions of force Milošević had direct legal control over—Serbia's State Security Service and Ministry of Interior—were his principal means of control over Croatian and Bosnian Serbs and instruments in the aggression against BiH even after its international recognition. [less ▲]

Transformationen des Bösen : Zur Adaption in Francis Ford Coppolas BRAM STOKER’S DRACULA

Presentation (2009, February)

Recent windmusic Manuscripts of Luxemburgian „National“ composer Laurent Menager

in IGEB Mitteilungsblatt (2009)

Infinitary aggregation

in Bodenhofer, Ulrich; De Baets, Bernard; Klement, Erich Peter (Eds.) et al Proc. 30th Linz Seminar on Fuzzy Set Theory (LINZ 2009): The Legacy of 30 Seminars – Where Do We Stand and Where Do We Go? (2009, February)

In this paper, based on [12, 18], we present infinitary aggregation functions on sequences possessing some a priori given properties. General infinitary aggregation is also discussed, and the connection ... [more ▼]

In this paper, based on [12, 18], we present infinitary aggregation functions on sequences possessing some a priori given properties. General infinitary aggregation is also discussed, and the connection with integrals, e.g., Lebesgue, Choquet and Sugeno integrals, is given. [less ▲]

Aggregation on bipolar scales

in Bodenhofer, Ulrich; De Baets, Bernard; Klement, Erich Peter (Eds.) et al Proc. 30th Linz Seminar on Fuzzy Set Theory (LINZ 2009): The Legacy of 30 Seminars – Where Do We Stand and Where Do We Go? (2009, February)

Behavioral analysis of aggregation functions

in Bodenhofer, Ulrich; De Baets, Bernard; Klement, Erich Peter (Eds.) et al Proc. 30th Linz Seminar on Fuzzy Set Theory (LINZ 2009): The Legacy of 30 Seminars – Where Do We Stand and Where Do We Go? (2009, February)