Grußwort des Senators für Wissenschaft und Forschung

Der vorliegende Band dokumentiert Reden, die zur Amtseinführung von Prof. Dr.-Ing. habil. Monika Auweter-Kurtz als Präsidentin der Universität Hamburg am 1. Februar 2007 gehalten wurden.This volume documents speeches given at the inauguration of Prof. Dr. -Ing. habil. Monika Auweter-Kurtz as President of the University of Hamburg on 1 February 200

Theoretical Limits of Backscatter Communications

Backscatter communication is a hot candidate for future IoT systems. It offers the possibility for connectivity with tiny amounts of energy that can be easily obtained from energy harvesting. This is possible as backscatter devices do not actively transmit electromagnetic waves. Instead they only reflect existing electromagnetic waves by changing the antenna load. This fact leads to significant differences compared to classical communication wrt. the modulation schemes and achievable data rates. However, to our best knowledge nobody has so far systematically analyzed the achievable data rates and transmit ranges for different parameter configurations. Within this paper we derive theoretical bounds for backscatter communications based on classical information theory. We then use these bounds to analyze how different parameters - e.g. the distance, the frequency, or the transmit power - affect the achievable data rates. The bounds are derived for mono-static configuration, as well as for bi-static configurations. This allows feasibility analyses for different use-cases that are currently discussed in 3GPP and IEEE 802.Comment: v2: Subsection IV G "Influence of the Distance in a Bi-static Configuration" replaced by a new subsection about an Ambient Backscattering Configuration (Subsection IV G "Influence of the Distance in an Ambient Backscattering Configuration"

Cyclopropylmethyldiphosphates are substrates for sesquiterpene synthases: experimental and theoretical results

New homo-sesquiterpenes are accessible after conversion of presilphiperfolan-8β-ol synthase (BcBOT2) with cyclopropylmethyl analogs of farnesyl diphosphate, and this biotransformation is dependent on subtle structural refinements. Two of the three cyclisation products are homo variants of germacrene D and germacrene D-4-ol while the third product reported contains a new bicyclic backbone for which no analogue in nature has been described so far. The findings on diphosphate activation are discussed and rationalised by relaxed force constants and dissociation energies computed at the DFT level of theory

Rednerinnen und Redner

Der vorliegende Band dokumentiert Reden, die zur Amtseinführung von Prof. Dr.-Ing. habil. Monika Auweter-Kurtz als Präsidentin der Universität Hamburg am 1. Februar 2007 gehalten wurden.This volume documents speeches given at the inauguration of Prof. Dr. -Ing. habil. Monika Auweter-Kurtz as President of the University of Hamburg on 1 February 200

G.: uppaal/DMC – abstraction-based heuristics for directed model checking

Abstract. UPPAAL/DMC is an extension of UPPAAL that provides generic heuristics for directed model checking. In this approach, the traversal of the state space is guided by a heuristic function which estimates the distance of a search state to the nearest error state. Our tool combines two recent approaches to design such estimation functions. Both are based on computing an abstraction of the system and using the error distance in this abstraction as the heuristic value. The abstractions, and thus the heuristic functions, are generated fully automatically and do not need any additional user input. UPPAAL/DMC needs less time and memory to find shorter error paths than UPPAAL’s standard search methods.