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See detailMM-Based Solution for Partially Connected Hybrid Transceivers with Large Scale Antenna Arrays
Arora, Aakash UL; Tsinos, Christos UL; Shankar, Bhavani UL et al

in Proc. 2019 IEEE Global Communications Conference (GLOBECOM) (in press)

In a mmWave multiple-input multiple-output (MIMO) communication system employing a large-scale antenna array (LSAA), the hybrid transceivers are used to reduce the power consumption and the hardware cost ... [more ▼]

In a mmWave multiple-input multiple-output (MIMO) communication system employing a large-scale antenna array (LSAA), the hybrid transceivers are used to reduce the power consumption and the hardware cost. In a hybrid analog-digital (A/D) transceiver, the pre/post-processing operation splits into a lower-dimensional baseband (BB) pre/postcoder, followed by a network of analog phase shifters. Primarily two kinds of hybrid architectures are proposed in the literature to implement hybrid transceivers namely, the fully-connected and the partially-connected. Implementation of fully-connected architecture has higher hardware complexity, cost and power consumption in comparison with partially-connected. In this paper, we focus on partially-connected hybrid architecture and develop a low-complexity algorithm for transceiver design for a single user point-to-point mmWave MIMO system. The proposed algorithm utilizes the variable elimination (projection) and the minorization-maximization (MM) frameworks and has convergence guarantees to a stationary point. Simulation results demonstrate that the proposed algorithm is easily scalable for LSAA systems and achieves significantly improved performance in terms of the spectral efficiency (SE) of the system compared to the state-of-the-art solution. [less ▲]

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See detailHybrid Transceivers Design for Large-Scale Antenna Arrays Using Majorization-Minimization Algorithms
Arora, Aakash UL; Tsinos, Christos UL; Shankar, Bhavani UL et al

in IEEE Transactions on Signal Processing (in press)

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See detailHybrid Analog-Digital Precoding Design for Satellite Systems
Arora, Aakash UL; Tsinos, Christos UL; Shankar, Bhavani UL et al

in Proc. 37th International Communications Satellite Systems Conference (ICSSC'19) (in press)

The work investigates the feasibility of massive MIMO in SatCom. Towards this, the necessary channel models, system parameters and scenarios are identified and a basic simulator developed. The work then ... [more ▼]

The work investigates the feasibility of massive MIMO in SatCom. Towards this, the necessary channel models, system parameters and scenarios are identified and a basic simulator developed. The work then considers an efficient implementation of the massive MIMO transmission through the use of hybrid analog/digital precoder. Efficient algorithmic solutions are proposed for the partially connected precoder architecture which enables efficiency in power/ hardware complexity and its performance evaluated. [less ▲]

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See detailMajorization-Minimization Algorithms for Analog Beamforming with Large-Scale Antenna Arrays
Arora, Aakash UL; Tsinos, Christos UL; Shankar, Bhavani UL et al

in Proc. 7th IEEE Global Conference on Signal and Information Processing (GlobalSIP) 2019 (in press)

Beamforming with large-scale antenna arrays (LSAA) is one of the predominant operations in designing wireless communication systems. However, the implementation of a fully digital system significantly ... [more ▼]

Beamforming with large-scale antenna arrays (LSAA) is one of the predominant operations in designing wireless communication systems. However, the implementation of a fully digital system significantly increases the number of required radio-frequency (RF) chains, which may be prohibitive. Thus, analog beamforming based on a phase-shifting network driven by a variable gain amplifier (VGA) is a potential alternative technology. In this paper, we cast the beamforming vector design problem as a beampattern matching problem, with an unknown power gain. This is formulated as a unit-modulus least-squares (ULS) problem where the optimal gain of the VGA is also designed in addition to the beamforming vector. We also consider a scenario where the receivers have the additional processing capability to adjust the phases of the incoming signals to mitigate specular multipath components. We propose efficient majorization-minimization (MM) based algorithms with convergence guarantees to a stationary point for solving both variants of the proposed ULS problem. Numerical results verify the effectiveness of the proposed solution in comparison with the existing state-of-the-art techniques. [less ▲]

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See detailSpecification Patterns for Robotic Missions
Menghi, Claudio UL; Tsigkanos, Christos; Pelliccione, Pelliccione et al

in IEEE Transactions on Software Engineering (in press)

Mobile and general-purpose robots increasingly support our everyday life, requiring dependable robotics control software. Creating such software mainly amounts to implementing their complex behaviors ... [more ▼]

Mobile and general-purpose robots increasingly support our everyday life, requiring dependable robotics control software. Creating such software mainly amounts to implementing their complex behaviors known as missions. Recognizing this need, a large number of domain-specific specification languages has been proposed. These, in addition to traditional logical languages, allow the use of formally specified missions for synthesis, verification, simulation or guiding implementation. For instance, the logical language LTL is commonly used by experts to specify missions as an input for planners, which synthesize the behavior a robot should have. Unfortunately, domain-specific languages are usually tied to specific robot models, while logical languages such as LTL are difficult to use by non-experts. We present a catalog of 22 mission specification patterns for mobile robots, together with tooling for instantiating, composing, and compiling the patterns to create mission specifications. The patterns provide solutions for recurrent specification problems, each of which detailing the usage intent, known uses, relationships to other patterns, and-most importantly-a template mission specification in temporal logic. Our tooling produces specifications expressed in the temporal logics LTL and CTL to be used by planners, simulators or model checkers. The patterns originate from 245 realistic textual mission requirements extracted from the robotics literature, and they are evaluated upon a total of 441 real-world mission requirements and 1251 mission specifications. Five of these reflect scenarios we defined with two well-known industrial partners developing human-size robots. We validated our patterns' correctness with simulators and two different types of real robots. [less ▲]

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See detailHegemonic University Tales: Discussing Narrative Positioning within the Academic Field between Humboldtian and Managerial Governance
Lueg, Klarissa; Graf, Angela; Powell, Justin J W UL

in Lueg, Klarissa; Lundholt, Marianne (Eds.) The Routledge Handbook of Counter-Narratives. (in press)

This chapter observes and analyzes hegemonic narratives in and of the academic field. In particular, our focus is on normative and evaluative accounts relating to forms of university governance. We ... [more ▼]

This chapter observes and analyzes hegemonic narratives in and of the academic field. In particular, our focus is on normative and evaluative accounts relating to forms of university governance. We suggest centering on two overarching approaches to what is seen as legitimate in terms of governing the university. First, we trace the age-old Humboldtian perspective, representing especially professorial independence and self-governance. Second, we consider the newer managerial perspective, separating top-down university management decision-making separate from (or counter to) faculty influence. We find that, as the latter form is currently taking hold within European universities, scholarly remembrance of the former Humboldtian governance tradition has morphed into a nearly uncritical, hegemonic tale of a glorified past. In contrast, we suggest, the managerial perspective represents a powerful ante-narrative, a hegemonic story in-the-making. The morally laden, and somewhat fantastical, Humboldtian tale, being itself hegemonic, is unfit to serve as a critical counter-narrative vis-à-vis the managerial approach that has attained considerable authority. Thus, we argue that contemporary governance discourse is suspended between two poles: the Humboldtian perspective, favoring professorial power and authority relations, and the managerial perspective, subordinating faculty under market considerations and continuous evaluation. The dilemma arising from this “suspension” also renders the governance discourse into regions of impracticality and elitism. We argue that a counter-narrative fit to challenge the managerialist governance structures in practice is lacking, with elitism continuously reproduced in-between an ancient hegemonic narrative (Humboldtian) and equally hegemonic contemporary ante-narrative (managerialist). [less ▲]

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See detail§§ 53a bis 56 AktG zur Gleichbehandlung der Aktionäre und Nebenabreden mit Aktionären
Zetzsche, Dirk Andreas UL

in Zetzsche, Dirk Andreas; Noack, Ulrich (Eds.) Kölner Kommentar zum Aktiengesetz (in press)

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See detail§§ 675u - 676c zur Haftung des Zahlungsdienstleisters, Münch. Kommentar zum Bürgerlichen Gesetzbuch
Zetzsche, Dirk Andreas UL

in Zetzsche, Dirk Andreas (Ed.) §§ 675u - 676c zur Haftung des Zahlungsdienstleisters, Münch. Kommentar zum Bürgerlichen Gesetzbuch (in press)

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See detail§§ 325 bis 329 HGB zur Publizität der Rechnungslegung von Handelsgesellschaften
Zetzsche, Dirk Andreas UL

in Rechnungslegungsrecht (in press)

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See detailEuropäisches Kapitalmarktrecht: Intermediärsrecht (§ 13)
Zetzsche, Dirk Andreas UL; Preiner, Christina

in Enzyklopädie des Europarechts, Europäisches Privat- und Unternehmensrecht, Band 6 (in press)

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See detailEuropäisches Kapitalmarktrecht: Marktmissbrauchsrecht (§ 14)
Zetzsche, Dirk Andreas UL

in Enzyklopädie des Europarechts, Europäisches Privat- und Unternehmensrecht, Band 6 (in press)

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See detailEuropäisches Kapitalmarktrecht: Grundlagen (§ 12)
Zetzsche, Dirk Andreas UL; Veidt, Robin UL

in Enzyklopädie des Europarechts, Europäisches Privat- und Unternehmensrecht, Band 6 (in press)

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See detailEuropäisches Kapitalmarktrecht: Unternehmenskapitalmarktrecht (§ 15)
Zetzsche, Dirk Andreas UL

in Enzyklopädie des Europarechts, Europäisches Privat- und Unternehmensrecht, Band 6 (in press)

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See detail§§ 54 bis 57 WpHG betreffend Positionslimits und Positionsmanagementkontrollen bei Warenderivaten und Positionsmeldungen
Zetzsche, Dirk Andreas UL; Lehmann, Mattias

in Kapitalmarktrechtskommentar (in press)

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See detailEinleitung, §§ 4 -9, 16, 29 bis 39c, 59 bis 68 des Wertpapiererwerbs- und Übernahmegesetzes
Zetzsche, Dirk Andreas UL; Noack, Ulrich

in Schwark; Zimmer (Eds.) Kapitalmarktrechtskommentar (in press)

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See detail§ 53 WpHG betreffend Leerverkäufe
Zetzsche, Dirk Andreas UL; Lehmann, Mattias

in Schwark; Zimmer (Eds.) Kapitalmarktrechtskommentar (in press)

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See detail§§ 6 bis 15 WpHG betreffend die Eingriffsbefugnisse der BaFin und Positionskontrollen
Zetzsche, Dirk Andreas UL; Lehmann, Mattias

in Schwark; Zimmer (Eds.) Kapitalmarktrechtskommentar (in press)

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See detailThe AIFM Directive– European Regulation of Alternative Investment Funds
Zetzsche, Dirk Andreas UL

Book published by Kluwer Law International - 3rd ed. (in press)

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See detailRegulating Libra
Zetzsche, Dirk Andreas UL; Buckley; Arner

in Oxford Journal of Legal Studies (in press)

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See detailThe EU’s Future of Data-Driven Finance
Zetzsche, Dirk Andreas UL; Buckley, Ross; Arner, Douglas et al

in Common Market Law Review (in press)

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