@article{7301, author = {{Höpfner, Henning and Fritsche, Carola and Ludwig, Arne and Ludwig, Astrid and Stromberg, Frank and Wende, Heiko and Keune, Werner and Reuter, Dirk and Wieck, Andreas D. and Gerhardt, Nils C. and Hofmann, Martin R.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{11}}, publisher = {{AIP Publishing}}, title = {{{Magnetic field dependence of the spin relaxation length in spin light-emitting diodes}}}, doi = {{10.1063/1.4752162}}, volume = {{101}}, year = {{2012}}, } @article{7302, author = {{Varwig, S. and Schwan, A. and Barmscheid, D. and Müller, C. and Greilich, A. and Yugova, I. A. and Yakovlev, D. R. and Reuter, Dirk and Wieck, A. D. and Bayer, M.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{7}}, publisher = {{American Physical Society (APS)}}, title = {{{Hole spin precession in a (In,Ga)As quantum dot ensemble: From resonant spin amplification to spin mode locking}}}, doi = {{10.1103/physrevb.86.075321}}, volume = {{86}}, year = {{2012}}, } @article{7303, author = {{Ganczarczyk, A. and Rojek, S. and Quindeau, A. and Geller, M. and Hucht, A. and Notthoff, C. and König, J. and Lorke, A. and Reuter, Dirk and Wieck, A. D.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{8}}, publisher = {{American Physical Society (APS)}}, title = {{{Transverse rectification in density-modulated two-dimensional electron gases}}}, doi = {{10.1103/physrevb.86.085309}}, volume = {{86}}, year = {{2012}}, } @article{7312, author = {{Beckel, Andreas and Zhou, Daming and Marquardt, Bastian and Reuter, Dirk and Wieck, Andreas D. and Geller, Martin and Lorke, Axel}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{23}}, publisher = {{AIP Publishing}}, title = {{{Momentum matching in the tunneling between 2-dimensional and 0-dimensional electron systems}}}, doi = {{10.1063/1.4728114}}, volume = {{100}}, year = {{2012}}, } @article{7313, author = {{Schwan, A. and Varwig, S. and Greilich, A. and Yakovlev, D. R. and Reuter, Dirk and Wieck, A. D. and Bayer, M.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{23}}, publisher = {{AIP Publishing}}, title = {{{Non-resonant optical excitation of mode-locked electron spin coherence in (In,Ga)As/GaAs quantum dot ensemble}}}, doi = {{10.1063/1.4726264}}, volume = {{100}}, year = {{2012}}, } @article{7315, author = {{Buchholz, Sven S. and Sternemann, Elmar and Chiatti, Olivio and Reuter, Dirk and Wieck, Andreas D. and Fischer, Saskia F.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{23}}, publisher = {{American Physical Society (APS)}}, title = {{{Noise thermometry in narrow two-dimensional electron gas heat baths connected to a quasi-one-dimensional interferometer}}}, doi = {{10.1103/physrevb.85.235301}}, volume = {{85}}, year = {{2012}}, } @article{7324, author = {{Kurtze, H. and Yakovlev, D. R. and Reuter, Dirk and Wieck, A. D. and Bayer, M.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{19}}, publisher = {{American Physical Society (APS)}}, title = {{{Hyperfine interaction mediated exciton spin relaxation in (In,Ga)As quantum dots}}}, doi = {{10.1103/physrevb.85.195303}}, volume = {{85}}, year = {{2012}}, } @article{7325, author = {{Schuster, J and Kim, T Y and Batke, E and Reuter, Dirk and Wieck, A D}}, issn = {{0953-8984}}, journal = {{Journal of Physics: Condensed Matter}}, number = {{16}}, publisher = {{IOP Publishing}}, title = {{{Photoluminescence lineshape features of carbon δ-doped GaAs heterostructures}}}, doi = {{10.1088/0953-8984/24/16/165801}}, volume = {{24}}, year = {{2012}}, } @article{7326, author = {{Bryja, L. and Jadczak, J. and Wójs, A. and Bartsch, G. and Yakovlev, D. R. and Bayer, M. and Plochocka, P. and Potemski, M. and Reuter, Dirk and Wieck, A. D.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{16}}, publisher = {{American Physical Society (APS)}}, title = {{{Cyclotron-resonant exciton transfer between the nearly free and strongly localized radiative states of a two-dimensional hole gas in a high magnetic field}}}, doi = {{10.1103/physrevb.85.165308}}, volume = {{85}}, year = {{2012}}, } @article{7327, author = {{Huang, J. and Chen, Y. S. and Ludwig, A. and Reuter, Dirk and Wieck, A. D. and Bacher, G.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{13}}, publisher = {{AIP Publishing}}, title = {{{Electron-nuclei spin coupling in GaAs—Free versus localized electrons}}}, doi = {{10.1063/1.3699261}}, volume = {{100}}, year = {{2012}}, } @article{7329, author = {{Houel, J. and Kuhlmann, A. V. and Greuter, L. and Xue, F. and Poggio, M. and Gerardot, B. D. and Dalgarno, P. A. and Badolato, A. and Petroff, P. M. and Ludwig, A. and Reuter, Dirk and Wieck, A. D. and Warburton, R. J.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{10}}, publisher = {{American Physical Society (APS)}}, title = {{{Probing Single-Charge Fluctuations at aGaAs/AlAsInterface Using Laser Spectroscopy on a Nearby InGaAs Quantum Dot}}}, doi = {{10.1103/physrevlett.108.107401}}, volume = {{108}}, year = {{2012}}, } @article{7330, author = {{Chen, J. C. H. and Wang, D. Q. and Klochan, O. and Micolich, A. P. and Das Gupta, K. and Sfigakis, F. and Ritchie, D. A. and Reuter, Dirk and Wieck, A. D. and Hamilton, A. R.}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{5}}, publisher = {{AIP Publishing}}, title = {{{Fabrication and characterization of ambipolar devices on an undoped AlGaAs/GaAs heterostructure}}}, doi = {{10.1063/1.3673837}}, volume = {{100}}, year = {{2012}}, } @inproceedings{7334, author = {{Höpfner, Henning and Li, Mingyuan and Ludwig, Arne and Ludwig, Astrid and Stromberg, Frank and Wende, Heiko and Keune, Werner and Reuter, Dirk and Wieck, Andreas D. and Gerhardt, Nils C. and Hofmann, Martin R.}}, booktitle = {{Ultrafast Phenomena and Nanophotonics XVI}}, publisher = {{SPIE}}, title = {{{Room temperature spin relaxation in quantum dot based spin-optoelectronic devices}}}, doi = {{10.1117/12.907821}}, year = {{2012}}, } @article{7338, author = {{Li, Yan and Sinitsyn, N. and Smith, D. L. and Reuter, Dirk and Wieck, A. D. and Yakovlev, D. R. and Bayer, M. and Crooker, S. A.}}, issn = {{0031-9007}}, journal = {{Physical Review Letters}}, number = {{18}}, publisher = {{American Physical Society (APS)}}, title = {{{Intrinsic Spin Fluctuations Reveal the Dynamical Response Function of Holes Coupled to Nuclear Spin Baths in (In,Ga)As Quantum Dots}}}, doi = {{10.1103/physrevlett.108.186603}}, volume = {{108}}, year = {{2012}}, } @article{7339, author = {{Dumslaff, Uwe and Engels, Gregor and Kremer, Marion}}, journal = {{OBJEKTspektrum}}, number = {{Nr. 5}}, pages = {{52 -- 57}}, title = {{{IT ist nicht gleich IT: Ein Plädoyer für eine situationsbezogene Softwareentwicklung}}}, year = {{2012}}, } @article{7340, author = {{Luckey, Markus and Erwig, Martin and Engels, Gregor}}, issn = {{1045-926X}}, journal = {{Journal of Visual Languages & Computing}}, number = {{5}}, pages = {{267--286}}, publisher = {{Elsevier BV}}, title = {{{Systematic evolution of model-based spreadsheet applications}}}, doi = {{10.1016/j.jvlc.2011.11.009}}, volume = {{23}}, year = {{2012}}, } @article{7342, author = {{Chernilovskaya, Anna and Gehrke, Mai and van Rooijen, Lorijn}}, issn = {{1367-0751}}, journal = {{Logic Journal of IGPL}}, number = {{6}}, pages = {{1110--1132}}, publisher = {{Oxford University Press (OUP)}}, title = {{{Generalized Kripke semantics for the Lambek-Grishin calculus}}}, doi = {{10.1093/jigpal/jzr051}}, volume = {{20}}, year = {{2012}}, } @article{7344, author = {{Grieger, Marvin and Güldali, Baris and Sauer, Stefan}}, journal = {{Softwaretechnik-Trends, Proceedings of the 14th Workshop Software-Reengineering (WSR)}}, number = {{2}}, pages = {{37--38}}, title = {{{Sichern der Zukunftsfähigkeit bei der Migration von Legacy-Systemen durch modellgetriebene Softwareentwicklung}}}, volume = {{32}}, year = {{2012}}, } @article{7345, author = {{Engels, Gregor and Whittle, Jon }}, issn = {{1619-1366}}, journal = {{Software & Systems Modeling}}, number = {{4}}, pages = {{463--465}}, publisher = {{Springer Nature}}, title = {{{Ten years of software and systems modeling}}}, doi = {{10.1007/s10270-012-0287-3}}, volume = {{11}}, year = {{2012}}, } @article{7351, author = {{Christ, Fabian and Nagel, Benjamin and Bachman-Gmür, Reto and Westenthaler, Rupert}}, journal = {{JavaMagazin}}, pages = {{96--100}}, title = {{{Semantisches Content Management}}}, volume = {{8}}, year = {{2012}}, } @article{7352, abstract = {{Mittlerweile sind viele Unternehmen dazu übergegangen, ihre Software „agil“ zu entwickeln. Die damit verbundenen Erwartungen sind vor allem ein frühes Kundenfeedback sowie eine kürzere „Time-to-Market“ durch entsprechend schnelle Release-Zyklen. Hinter den Kulissen finden sich jedoch oftmals Probleme, sodass die erwarteten Vorteile agiler Softwareentwicklung nicht oder nur teilweise zum Tragen kommen. Gründe dafür liegen selten an technischen Hürden, sondern oftmals in einer zu oberflächlichen Interpretation der Philosophie von agiler Softwareentwicklung und den damit zusammenhängenden Kernzielen: Planung und Analyse auf ein sinnvolles Maß zu reduzieren und zugleich unnötige Arbeiten zu vermeiden. Was sinnvoll und was unnötig ist, stellt dabei eine der wesentlichen Herausforderungen dar.}}, author = {{Geisen, Silke and Güldali, Baris}}, journal = {{OBJEKTspektrum (Online Themenspecials)}}, number = {{Agility/2012}}, pages = {{1--4}}, title = {{{Agiles Testen in Scrum – Testtypen und Abläufe}}}, year = {{2012}}, } @article{7490, author = {{Ruth, Marcel and Meier, Cedrik}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{22}}, publisher = {{American Physical Society (APS)}}, title = {{{Scaling coefficient for three-dimensional grain coalescence of ZnO on Si(111)}}}, doi = {{10.1103/physrevb.86.224108}}, volume = {{86}}, year = {{2012}}, } @article{7491, author = {{Kröger, Philipp and Ruth, Marcel and Weber, Nils and Meier, Cedrik}}, issn = {{0003-6951}}, journal = {{Applied Physics Letters}}, number = {{26}}, publisher = {{AIP Publishing}}, title = {{{Carrier localization in ZnO quantum wires}}}, doi = {{10.1063/1.4731767}}, volume = {{100}}, year = {{2012}}, } @article{7492, author = {{Kampmeier, J. and Rashad, M. and Woggon, U. and Ruth, M. and Meier, Cedrik and Schikora, D. and Lischka, K. and Pawlis, A.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{15}}, publisher = {{American Physical Society (APS)}}, title = {{{Enhanced photoluminescence of colloidal nanocrystals embedded in epitaxially grown semiconductor microstructures}}}, doi = {{10.1103/physrevb.85.155405}}, volume = {{85}}, year = {{2012}}, } @book{7507, author = {{Kremer, Marion and Engels, Gregor and Hofmann, Alexander and Hohwiller, Jörg and E. Nandico, Oliver and Nötzold, Thomas and Prott, Karl and Schlegel, Diethelm and Seidl, Andreas and Wolf, Thomas}}, publisher = {{Capgemini CSD Research, Offenbach 2012}}, title = {{{Quasar 3.0 - A Situational Approach to Software Engineering}}}, year = {{2012}}, } @inbook{7557, abstract = {{Software systems are part of our everyday life and they become more complex day by day. The ever-growing complexity of software and high quality requirements pose tough challenges to quality assurance. The quality of a software system can be measured by software testing. However, if manually done, testing is a time-consuming and error-prone task. Especially test case design and test execution are the most cost-intensive activities in testing. In the previous 20 years, many automation tools have been introduced for automating test execution by using test scripts. However, the effort for creating and maintaining test scripts remains. Model-based testing (MBT) aims at improving this part by systematizing and automating the test case design. Thereby, test cases or automatable test scripts can be generated systematically from test models. MBT is already known for several years, but it currently gains a great momentum due to advanced tool support and innovative methodological approaches. This chapter aims at giving an overview of MBT and summarizes recent achievements in MBT. Experiences with using the MBT approach are illustrated by reporting on some success stories. Finally, open issues and future research challenges are discussed.}}, author = {{Mlynarski, Michael and Güldali, Baris and Weißleder, Stephan and Engels, Gregor}}, booktitle = {{Advances in Computers}}, editor = {{ Hurson, Ali and Memon, Atif}}, pages = {{1 -- 39}}, publisher = {{Elsevier}}, title = {{{Model-Based Testing: Achievements and Future Challenges}}}, doi = {{http://dx.doi.org/10.1016/B978-0-12-396535-6.00001-6}}, volume = {{86}}, year = {{2012}}, } @phdthesis{7572, abstract = {{Software-Architekturen betrieblicher Informationssysteme bestehen aus Architekturbausteinen wie Frameworks, Komponenten und Bibliotheken. Die Entwicklung dieser Architekturen unter Einbeziehung wiederverwendbarer Architekturbausteine ist eine Voraussetzung einer industriell organisierten Software-Entwicklung. Für eine effiziente Trennung der Zuständigkeiten werden dabei häufig Architekturbausteine von Drittanbietern wiederverwendet.Frameworks als erweiterbare Architekturbausteine bieten besondere Vorteile. Sie erlauben sowohl die Wiederverwendung der Funktionalität als auch der durch das Framework vorgegebenen Software-Architektur. Beispiele sind Frameworks für Benutzungsoberflächen oder für die Anbindung von Datenbanken. Durch Implementierung anwendungsspezifischer Erweiterungen wird ein Framework für den konkreten Anwendungsfall angepasst. Eine Anwendung, deren Software-Architektur ein Framework einsetzt, benutzt das Framework über dessen Erweiterungspunkte.Im Laufe der Evolution einer solchen Anwendung entsteht häufig die Situation, dass das Framework durch eine neuere Version aktualisiert werden soll. Die Aktualisierung enthält das Risiko, dass Inkompatibilitäten zwischen bestehender Anwendung und neuer Framework-Version auftreten, die wiederum zu aufwendigen Anpassungen führen. Daher müssen mögliche Inkompatibilitäten vor der Aktualisierung erkannt und bewertet werden. Nach aktuellem Stand der Technik ist dies nicht möglich, so dass es in der industriellen Praxis zu unvorhergesehenen Problemen verbunden mit hohen Kosten kommt.Wir stellen ein Verfahren zur automatischen Kompatibilitätsanalyse Framework-basierter Anwendungen vor, mit dem das beschriebene Problem gelöst wird. Durch eine Kombination aus Codeanalyse und neuartiger Framework-Beschreibung lassen sich mögliche Inkompatibilitäten vor Durchführung der Aktualisierung automatisch berechnen. Eine prototypische Implementierung des Verfahrens im Werkzeug »Companian« demonstriert die praktische Einsetzbarkeit unseres Verfahrens.Für die Definition der benötigten Framework-Beschreibungssprache mittels Meta-Modellierung setzen wir die neuartige Modellierungstechnik der parametrisierten Meta-Modelle ein. Die Technik unterstützt unseren Ansatz einer anforderungsbasierten Wiederverwendung von Sprachen. Mit diesem Ansatz können bestehende Sprachen für Teilaspekte neu definierter Sprachen wiederverwendet werden. Unser pragmatischer Ansatz stellt dabei sicher, dass hierbei nur die Sprachen benutzt werden können, die syntaktisch und semantisch den geforderten Sprachen entsprechen.}}, author = {{Christ, Fabian}}, publisher = {{Universität Paderborn}}, title = {{{Automatische Kompatibilitätsprüfung Framework-basierter Anwendungen}}}, year = {{2012}}, } @inproceedings{8473, author = {{Gerth, Christian and Luckey, Markus }}, booktitle = {{Proceedings of the Workshop on Comparison and Versioning of Software Models (CVSM'12)}}, number = {{4}}, pages = {{32--34}}, publisher = {{FG Softwaretechnik, Gesellschaft für Informatik e.v. (GI)}}, title = {{{Towards Rich Change Management for Business Process Models}}}, volume = {{32}}, year = {{2012}}, } @inproceedings{8475, author = {{Huma , Zille and Gerth , Christian and Engels, Gregor and Juwig, Oliver }}, booktitle = {{Proceedings of the Forum at the CAiSE'12 Conference on Advanced Information Systems Engineering}}, pages = {{90----97}}, publisher = {{CEUR-WS.org}}, title = {{{A UML-based Rich Service Description Language for Automatic Service Discovery of Heterogeneous Service Partners}}}, doi = {{http://ceur-ws.org/Vol-855/paper11.pdf}}, volume = {{855}}, year = {{2012}}, } @inproceedings{8476, author = {{Luckey , Markus and Mutz, Felix }}, booktitle = {{Repository for Model-Driven Development (ReMoDD)}}, title = {{{Modeling with Adapt Cases}}}, year = {{2012}}, } @inproceedings{8477, author = {{Geisen , Silke and Luckey , Markus and Engels, Gregor}}, booktitle = {{Proceedings of 19. GI-WIVM Workshop: Qualitätsmanagement und Vorgehensmodelle}}, pages = {{111--120}}, publisher = {{Shaker Verlag}}, title = {{{Ein Ansatz zur dynamischen Qualitätsmessung, -bewertung und Anpassung von Software Engineering Methoden}}}, year = {{2012}}, } @inproceedings{8478, author = {{Arifulina, Svetlana }}, booktitle = {{Proceedings of the Doctoral Symposium of the 5th International Conference on Software Language Engineering 2012, Dresden, Germany (SLE (Doctoral Symposium))}}, pages = {{23--26}}, publisher = {{CEUR-WS.org}}, title = {{{Towards a Framework for the Integration of Modeling Languages}}}, volume = {{935}}, year = {{2012}}, } @inproceedings{8479, author = {{Güldali , Baris and Sauer, Stefan and Löhr, Perdita }}, booktitle = {{Proceedings of the Workshop Modellbasierte und Modellgetriebene Softwaremodernisierung (MMSM 2012)}}, number = {{2}}, pages = {{5--6}}, publisher = {{Softwaretechnik-Trends}}, title = {{{Entwicklung eines Softwarewerkzeugs für die modellgetriebene Migration betrieblicher Informationssysteme}}}, volume = {{32}}, year = {{2012}}, } @inproceedings{8480, author = {{Mussbacher , Gunter and Alam , Omar and Alhaj , Mohammed and Ali , Shaukat and Amálio , Nuno and Barn , Balbir and Bræk , Rolv and Clark , Tony and Combemale , Benoit and Cysneiros , Luiz Marcio and Fatima , Urooj and France , Robert and Georg , Geri and Horkoff , Jennifer and Kienzle , Jörg and Leite , Julio Cesar and Lethbridge , Timothy C. and Luckey , Markus and Moreira , Ana and Mutz , Felix and A. Oliveira, A. Padua and C. Petriu , Dorina and Schöttle, Matthias and Troup, Lucy and Werneck, Vera M. B. }}, booktitle = {{Proceedings of the Workshop about Comparing Modeling Approaches 2012 (@MODELS 2012)}}, publisher = {{ACM}}, title = {{{Assessing composition in modeling approaches}}}, doi = {{https://dl.acm.org/citation.cfm?id=2459032}}, year = {{2012}}, } @inproceedings{8483, author = {{Luckey , Markus and Thanos , Christian and Gerth, Christian and Engels, Gregor}}, booktitle = {{Proceedings of 1st International Workshop on EVALUATION for SELF-ADAPTIVE and SELF-ORGANIZING SYSTEMS at SASO'12}}, title = {{{Multi-Staged Quality Assurance for Self-Adaptive Systems}}}, year = {{2012}}, } @inproceedings{8484, author = {{Geisen, Silke }}, booktitle = {{Proceedings of Software Engineering 2012 (SE 2012) - Doktorandensymposium}}, pages = {{7--12}}, publisher = {{Petra Hofstedt, Claus Lewerentz (BTU Cottbus)}}, title = {{{Ein Ansatz zur Anpassung von Software Engineering Methoden im laufenden Projekt}}}, volume = {{Report 01/12}}, year = {{2012}}, } @inproceedings{8548, author = {{Liebendörfer, Michael and Hochmuth, Reinhard}}, booktitle = {{Beiträge zum Mathematikunterricht 2012 : Vorträge auf der 46. Tagung für Didaktik der Mathematik}}, pages = {{545--548}}, publisher = {{WTM-Verlag}}, title = {{{Mathematikinteresse im 1. Studiensemester}}}, volume = {{1}}, year = {{2012}}, } @inproceedings{8552, author = {{Biehler, Rolf and Hoppenbrock, Axel and Klemm, Juliane and Liebendörfer, Michael and Wassong, Thomas}}, booktitle = {{CETL-MSOR Conference 2011}}, title = {{{Training of student teaching assistants and e-learning via math-bridge – Two projects at the German Centre for Higher Mathematics Education}}}, year = {{2012}}, } @article{8556, abstract = {{We consider the space of complete rank two collineations. Starting from its description as a limit of GIT-quotients of a Grassmanian G(2, n) by a certain {\textbackslash}documentclass\{article\}{\textbackslash}usepackage\{amssymb\}{\textbackslash}begin\{document\}{\textbackslash}pagestyle\{empty\}\${\textbackslash}mathbb \{C\}{\textasciicircum}*\${\textbackslash}end\{document\}-action, we determine the Cox ring by means of toric ambient modifications.}}, author = {{Hausen, Jürgen and Liebendörfer, Michael}}, issn = {{1522-2616}}, journal = {{Mathematische Nachrichten}}, number = {{8-9}}, pages = {{974--980}}, title = {{{The Cox ring of the space of complete rank two collineations}}}, doi = {{10.1002/mana.201100043}}, volume = {{285}}, year = {{2012}}, } @inbook{9587, author = {{Beutner, Marc and Kremer, H.-Hugo and Zoyke, A}}, booktitle = {{Individuelle Förderung und berufliche Orientierung im berufsschulischen Übergangssystem. Ergebnisse aus dem Forschungs- und Entwicklungsprojekt InLab}}, editor = {{Kremer, H.-H and Beutner, M and Zoyke, A}}, pages = {{7 -- 20}}, title = {{{Vorstellung des Modellprojekts InLab}}}, year = {{2012}}, } @inbook{9588, author = {{Beutner, Marc and Frehe, Petra and Gebbe, M and Gockel, C and Kremer, H.-Hugo and Zoyke, A}}, booktitle = {{Individuelle Förderung und berufliche Orientierung im berufsschulischen Übergangssystem. Ergebnisse aus dem Forschungs- und Entwicklungsprojekt InLab}}, editor = {{Kremer, H.-H and Beutner, M and Zoyke, A}}, pages = {{109 -- 149}}, title = {{{Vorstellung von vier Instrumenten zur Individuellen Förderung}}}, year = {{2012}}, } @inbook{9670, author = {{Strauß, Sara}}, booktitle = {{anglistik & englischunterricht}}, title = {{{Victorian Values in Nineteenth- and Twenty-First-Century Advertising and Consumer Practices}}}, year = {{2012}}, } @inbook{9699, author = {{Strauß, Sara}}, booktitle = {{Who’s afraid of...? Facets of Fear in Anglophone Literature and Film}}, editor = {{Gymnich, Marion}}, pages = {{141--156}}, publisher = {{V&R Unipress Bonn}}, title = {{{Facets of Children’s Fears in Twentieth- and Twenty-First-Century Stream-of-Consciousness Fiction}}}, year = {{2012}}, } @inbook{9700, author = {{Strauß, Sara}}, booktitle = {{A Hundred Years of The Secret Garden – Frances Hodgson Burnett’s Children’s Classic Revisited}}, editor = {{Gymnich, Marion and Lichterfeld, Imke}}, pages = {{77--89}}, publisher = {{V&R Unipress Bonn}}, title = {{{Constructions of ‘Otherness’ in Frances Hodgson Burnett’s The Secret Garden}}}, year = {{2012}}, } @misc{9701, booktitle = {{Critical Engagements: A Journal of Criticism and Theory: Special Section: Eva Figes}}, editor = {{Strauß, Sara}}, number = {{2}}, pages = {{95--108}}, title = {{{The Persistence of Modernism in Light}}}, volume = {{5}}, year = {{2012}}, } @misc{9733, abstract = {{Interview 11 Oct. 2012}}, author = {{Flotmann, Christina}}, publisher = {{Deutschlandfunk}}, title = {{{Der Zauber Magischer Welten}}}, year = {{2012}}, } @article{9781, abstract = {{A piezoelectric energy harvester is an electromechanical device that converts ambient mechanical vibration into electric power. Most existing vibration energy harvesting devices operate effectively at a single frequency only, dictated by the design of the device. This frequency must match the frequency of the host structure vibration. However, real world structural vibrations rarely have a specific constant frequency. Therefore, piezoelectric harvesters that generate usable power across a range of exciting frequencies are required to make this technology commercially viable. Currently known harvester tuning techniques have many limitations, in particular they miss the ability to work during harvester operation and most often cannot perform a precise tuning. This paper describes the design and testing of a vibration energy harvester with tunable resonance frequency, wherein the tuning is accomplished by changing the attraction force between two permanent magnets by adjusting the distance between the magnets. This tuning technique allows the natural frequency to be manipulated before and during operation of the harvester. Furthermore the paper presents a physical description of the frequency tuning effect. The experimental results achieved with a piezoelectric bimorph fit the calculated results very well. The calculation and experimental results show that using this tuning technique the natural frequency of the harvester can be varied efficiently within a wide range: in the test setup, the natural frequency of the piezoelectric bimorph could be increased by more than 70\%.}}, author = {{Al-Ashtari, Waleed and Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}}, journal = {{Smart Materials and Structures}}, number = {{3}}, pages = {{035019}}, title = {{{Frequency tuning of piezoelectric energy harvesters by magnetic force}}}, volume = {{21}}, year = {{2012}}, } @article{9782, abstract = {{Piezoelectric structures are nowadays used in many different applications. A better understanding of the influence of material properties and geometrical design on the performance of these structures helps to develop piezoelectric structures specifically designed for their application. Different equivalent circuits have been introduced in the literature to investigate the behaviour of piezoelectric transducers. The model parameters are usually determined from measurements covering the characteristic frequencies of the piezoelectric transducer. This article introduces an analytical technique for calculating the mechanical and electrical equivalent system parameters and characteristic frequencies based on material properties and geometry for a cantilever bimorph structure. The model is validated by measurements using a cantilever bimorph and fits the experimental results better than previous models. The model gives a full set of piezoelectric transducer parameters and is therefore well suited for further theoretical investigations of piezoelectric transducers for different applications. The results also show that even small manufacturing tolerances have a considerable effect on the system parameters and characteristic frequencies. This might lead to intolerable deviations, especially in dynamic applications and should be avoided by careful design and production.}}, author = {{Al-Ashtari, Waleed and Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}}, journal = {{Journal of Intelligent Material Systems and Structures}}, number = {{1}}, pages = {{15--23}}, title = {{{Analytical determination of characteristic frequencies and equivalent circuit parameters of a piezoelectric bimorph}}}, doi = {{10.1177/1045389X11430742}}, volume = {{23}}, year = {{2012}}, } @inproceedings{9783, abstract = {{To optimize the ultrasound irradiation for cavitation based ultrasound applications like sonochemistry or ultrasound cleaning, the correlation between cavitation intensity and the resulting effect on the process is of interest. Furthermore, changing conditions like temperature and pressure result in varying acoustic properties of the liquid. That might necessitate an adaption of the ultrasound irradiation. To detect such changes during operation, process monitoring is desired. Labor intensive processes, that might be carried out for several hours, also require process monitoring to increase their reliability by detection of changes or malfunctions during operation. In some applications cavitation detection and monitoring can be achieved by the application of sensors in the sound field. Though the application of sensors is possible, this necessitates modifications on the system and the sensor might disturb the sound field. In other applications harsh, process conditions prohibit the application of sensors in the sound field. Therefore alternative techniques for cavitation detection and monitoring are desired. The applicability of an external microphone and a self-sensing ultrasound transducer for cavitation detection were experimentally investigated. Both methods were found to be suitable and easily applicable.}}, author = {{Bornmann, Peter and Hemsel, Tobias and Sextro, Walter and Maeda, Takafumi and Morita, Takeshi}}, booktitle = {{Ultrasonics Symposium (IUS), 2012 IEEE International}}, issn = {{1948-5719}}, keywords = {{cavitation, chemical reactors, microphones, process monitoring, reliability, ultrasonic applications, ultrasonic waves, acoustic properties, cavitation based ultrasound applications, cavitation intensity, change detection reliability, external microphone, malfunction detection reliability, nonperturbing cavitation detection, nonperturbing cavitation monitoring, process monitoring, self-sensing ultrasound transducer, sonochemical reactors, sonochemistry, ultrasound cleaning, ultrasound irradiation, Acoustics, Liquids, Monitoring, Sensors, Sonar equipment, Transducers, Ultrasonic imaging}}, pages = {{1141--1144}}, title = {{{Non-perturbing cavitation detection / monitoring in sonochemical reactors}}}, doi = {{10.1109/ULTSYM.2012.0284}}, year = {{2012}}, } @inproceedings{9784, abstract = {{Piezoelectric inertia motors use the inertia of a body to drive it by means of a friction contact in a series of small steps. These motors can operate in ``stick-slip'' or ``slip-slip'' mode, with the fundamental frequency of the driving signal ranging from several Hertz to more than 100 kHz. To predict the motor characteristics, a Coulomb friction model is sufficient in many cases, but numerical simulation requires microscopic time steps. This contribution proposes a much faster simulation technique using one evaluation per period of the excitation signal. The proposed technique produces results very close to those of timestep simulation for ultrasonics inertia motors and allows direct determination of the steady-state velocity of an inertia motor from the motion profile of the driving part. Thus it is a useful simulation technique which can be applied in both analysis and design of inertia motors, especially for parameter studies and optimisation.}}, author = {{Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}}, booktitle = {{Ultrasonics Symposium (IUS), 2012 IEEE International}}, issn = {{1948-5719}}, keywords = {{friction, ultrasonic motors, Coulomb friction model, efficient simulation technique, friction contact, high-frequency piezoelectric inertia motor, motor characteristics prediction, numerical simulation, slip-slip mode, stick-slip mode, time-step simulation, ultrasonic inertia motor, Acceleration, Acoustics, Actuators, Computational modeling, Friction, Numerical models, Steady-state}}, pages = {{277--280}}, title = {{{An efficient simulation technique for high-frequency piezoelectric inertia motors}}}, doi = {{10.1109/ULTSYM.2012.0068}}, year = {{2012}}, } @inproceedings{9785, abstract = {{Hydrothermal method enables to synthesize high quality piezoelectric materials. To shorten the reaction time and to get higher quality materials, we propose an ultrasonic irradiation to the solution during the hydrothermal method. We named it ultrasonic assisted hydrothermal method (UAHTM). We have synthesized lead-free piezoelectric material and PZT thin film and the effect of UAHTM have been confirmed. In this study, we tried to improve UAHTM. First, to generate powerful and stable ultrasonic irradiation at high temperature on UAHTM, we developed a new transducer using LiNbO3 single crystal. Second, to prevent contamination to the materials, A Teflon cover on the tip of transducer was attached.}}, author = {{Isobe, Gaku and Ageba, Ryo and Maeda, Takafumi and Bornmann, Peter and Hemsel, Tobias and Morita, Takeshi}}, booktitle = {{AIP Conference Proceedings}}, editor = {{B. J. Linde, Bogumil and Paczkowski, Jacek and Ponikwicki, Nikodem}}, keywords = {{contamination, lead compounds, piezoelectric materials, piezoelectric thin films, piezoelectric transducers, ultrasonic effects}}, number = {{1}}, pages = {{569--572}}, publisher = {{AIP}}, title = {{{Synthesis of piezoelectric materials by ultrasonic assisted hydrothermal method}}}, doi = {{10.1063/1.3703251}}, volume = {{1433}}, year = {{2012}}, } @article{9786, abstract = {{Self-optimizing mechatronic systems are a new class of technical systems. On the one hand, new challenges regarding dependability arise from their additional complexity and adaptivity. On the other hand, their abilities enable new concepts and methods to improve the dependability of mechatronic systems. This paper introduces a multi-level dependability concept for selfoptimizing mechatronic systems and shows how probabilistic planning can be used to improve the availability and reliability of systems in the operating phase. The general idea to improve the availability of autonomous systems by applying probabilistic planning methods to avoid energy shortages is exemplified on the example of an innovative railway vehicle.}}, author = {{Klöpper, Benjamin and Sondermann-Wölke, Christoph and Romaus, Christoph}}, journal = {{Journal of Robotics and Mechatronics}}, keywords = {{self-optimizing systems, dependability, probabilistic planning, energy management}}, number = {{1}}, pages = {{5--15}}, title = {{{Probabilistic Planning for Predictive Condition Monitoring and Adaptation Within the Self-Optimizing Energy Management of an Autonomous Railway Vehicle}}}, volume = {{24}}, year = {{2012}}, } @inproceedings{9787, author = {{Kohl, Sergej and Sextro, Walter and Zuber, Armin}}, booktitle = {{8. Tag des Fahrwerks, Aachen, 2012}}, pages = {{38--60}}, title = {{{Benteler Vehicle Dynamics -- Fahrdynamikentwicklung basierend auf einer neuen Auslegungstheorie}}}, year = {{2012}}, } @inproceedings{9788, abstract = {{A hydrothermal method utilizes a crystallization process in the solution so that the pure and high-quality powders can be realized. Sintering from the hydrothermal KNbO3 and NaNbO3 powders, a high-dense lead-free piezoelectric (K,Na)NbO3 ceramics could be obtained (density: 98.8\%). Concerning about the g33 constant, high value as large as commercial PZT ceramics was measured. Therefore, the hydrothermal (K,Na)NbO3 ceramics is usable for the sensors and the energy harvesting devices. To demonstrate the (K,Na)NbO3 ceramics, a hydrophone sensor was fabricated and evaluated.}}, author = {{Maeda, Takafumi and Bornmann, Peter and Hemsel, Tobias and Morita, Takeshi}}, booktitle = {{Ultrasonics Symposium (IUS), 2012 IEEE International}}, issn = {{1948-5719}}, keywords = {{crystallisation, hydrophones, piezoceramics, potassium compounds, powder technology, powders, sensors, sintering, sodium compounds, (K0.48Na0.52)NbO3, KNbO3 powder, NaNbO3 powder, crystallization, energy harvesting devices, g33 constant, hydrophone sensor, hydrothermal lead-free (K0.48Na0.52)NbO3 ceramics, hydrothermal method, piezoelectric applications, sintering, Materials, Transducers}}, pages = {{194--195}}, title = {{{Piezoelectric applications of hydrothermal lead-free (K0.48Na0.52)NbO3 ceramics}}}, doi = {{10.1109/ULTSYM.2012.0048}}, year = {{2012}}, } @article{9789, abstract = {{[$Li_x(Na_0.52K_0.48)_1-x]NbO_3 (0 \leq x \leq 0.091)$ ceramics were synthesized using hydrothermal powders and the lithium doping content was controlled to optimize their piezoelectric properties. The raw KNbO$_3$ and NaNbO$_3$ powders were obtained separately by a hydrothermal method and LiNbO$_3$ powders were prepared by milling a commercial LiNbO$_3$ single crystal. These powders were mixed with ethanol at a molar ratio LiNbO$_3$: ($Na_0.52K_0.48$)NbO$_3 = x : 1-x$. The synthesized powders were sintered at 1060--1120 $\,^{\circ}$C for 2 h. We succeeded in obtaining highly dense [$Li_x(Na_0.52K_0.48)_1-x]NbO_3$ ceramics using hydrothermal powder. The X-ray diffraction patterns revealed that the crystal phase changed from orthorhombic to tetragonal at around x = 0.06. At this morphotropic phase boundary (MPB), the c/a ratio changed from 1.016 to 1.024 and the highest piezoelectric constant was obtained with the chemical component of [$Li_x(Na_0.52K_0.48)_1-x]NbO_3$. The obtained piezoelectric properties were as follows: $k_33 = 0.51, \epsilon 33^T/ \epsilon _0 = 836$ , $c_33^E = 46$ GPa, $d_33 = 203$ pC/N, and $T_c = 482 $\,^{\circ}$C$.}}, author = {{Maeda, Takafumi and Hemsel, Tobias and Morita, Takeshi}}, journal = {{Japanese Journal of Applied Physics}}, pages = {{09MD08}}, publisher = {{The Japan Society of Applied Physics}}, title = {{{Piezoelectric Properties of Li-Doped (K0.48Na0.52)NbO3 Ceramics Synthesized Using Hydrothermally-Derived KNbO3 and NaNbO3 Fine Powders}}}, doi = {{10.1143/JJAP.51.09MD08}}, volume = {{51}}, year = {{2012}}, } @inproceedings{9791, abstract = {{The rapid development of communication and information technology opens up fascinating perspectives, which go far beyond the state of the art in mechatronics: mechatronic systems with inherent partial intelligence. These so called self-optimizing systems adapt their objectives and behavior autonomously and flexibly to changing operating conditions. On the one hand, securing the dependability of such systems is challenging due to their complexity and non-deterministic behavior. On the other hand, self-optimization can be used to increase the dependability of the system during its operation. However, it has to be ensured, that the self-optimization works dependable itself. To cope with these challenges, the multi-level dependability concept was developed. It enables predictive condition monitoring, influences the objectives of the system and determines suitable means to improve the system's dependability during its operation. In this contribution we introduce a procedure for the conceptual design of an advanced condition monitoring based on the system's principle solution. The principle solution describes the principal operation mode of the system and its desired behavior. It is modeled using the specification technique for the domain-spanning description of the principle solution of a self-optimizing system and consists of a coherent system of eight partial models (e.g. requirements, active structure, system of objectives, behavior, etc.). The partial models are analyzed separately in order to derive the components of the multi-level dependability concept. In particular, the reliability analysis of the partial model active structure is performed to identify the system elements to be monitored and parameters to be measured. The principle solution is extended accordingly: e.g. with system elements required for the realization of the dependability concept. The advantages of the method are shown on the self-optimizing guidance module of a railroad vehicle.}}, author = {{Sondermann-Wölke , Christoph and Meyer, Tobias and Dorociak, Rafal and Gausemeier, Jürgen and Sextro, Walter}}, booktitle = {{Proceedings of the 11th International Probabilistic Safety Assessment and Management Conference (PSAM11) and The Annual European Safety and Reliability Conference (ESREL2012)}}, keywords = {{Mechatronic Systems, Principle Solution, Condition Monitoring, Conceptual Design}}, title = {{{Conceptual Design of Advanced Condition Monitoring for a Self-Optimizing System based on its Principle Solution}}}, year = {{2012}}, } @article{9806, abstract = {{Piezoelectric inertia motors, also known as ``stick-slip-drives'', use the inertia of a body to drive it by means of a friction contact in small steps. While these steps normally involve stiction and sliding, the motors can also operate in ``slip-slip'' mode without any phase of static friction. In this contribution, a one degree of freedom model of an inertia motor driven by an ideal actuator is analysed. Start-up and constant velocity operation of the motor are investigated and appropriate quantities to compare ``stick-slip'' and ``slip-slip'' operation are determined. Different aspects such as velocity, uniformity of motion, load capacity, robustness, efficiency, and wear are considered. The analysis allows both modes to be applied advantageously in different applications and can widen the field of application of piezoelectric inertia motors. Motor designers are enabled to choose the appropriate mode of operation and the best drive parameters for their individual applications.}}, author = {{Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}}, journal = {{ACTUATOR 2012 Conference Proceedings}}, keywords = {{Piezoelectric Inertia Motors, Drive Signals, Stick-slip, Slip-slip}}, pages = {{761--764}}, title = {{{Analysis of different operation modes for inertia motors}}}, year = {{2012}}, } @article{4095, abstract = {{Aiming to diminish the reflection losses of glass covered light harvesting devices, the optical reflectivity of nanostructured glass surfaces is studied theoretically and experimentally. The work is inspired by the nanoscale roughness of insect eyes, which is tried to be replicated on a technical glass surface. To this end, the reflectivity of glass surfaces with topographies represented by linear, parabolic and Fermishaped glass/air fill factor profiles is calculated for normal incidence. It is shown that using the latter ones, an almost complete suppression of reflections can be achieved. A simple, self-organization technique to create such Fermi-shaped filling factor profiles in glass experimentally is also presented.}}, author = {{Achtelik, J. and Sievers, W. and Lindner, Jörg}}, issn = {{0921-5107}}, journal = {{Materials Science and Engineering: B}}, location = {{Straßburg (France)}}, number = {{9}}, pages = {{635--638}}, publisher = {{Elsevier BV}}, title = {{{Biomimetic approaches to create anti-reflection glass surfaces for solar cells using self-organizing techniques}}}, doi = {{10.1016/j.mseb.2012.10.014}}, volume = {{178}}, year = {{2012}}, } @article{4104, abstract = {{We report on the molecular beam epitaxy growth of cubic GaN on 3C–SiC (001) nanostructures. Transmission electron microscopy (TEM) studies show phase-pure cubic GaN crystals with a low defect density on top of the post shaped 3C–SiC nanostructures and GaN grown on their sidewalls, which is dominated by {111} planar defects. The nanostructures, aligned parallel and perpendicular to the [110] directions of the substrate, are located in anti-phase domains of the 3C–SiC/Si (001) substrate. These anti-phase domains strongly influence the optimum growth of GaN layers in these regions. TEM measurements demonstrate a different stacking fault density in the cubic GaN epilayer in these areas.}}, author = {{Kemper, R.M. and Hiller, L. and Stauden, T. and Pezoldt, J. and Duschik, K. and Niendorf, T. and Maier, H.J. and Meertens, D. and Tillmann, K. and As, D.J. and Lindner, Jörg}}, issn = {{0022-0248}}, journal = {{Journal of Crystal Growth}}, location = {{Nara (Japan)}}, pages = {{291--294}}, publisher = {{Elsevier BV}}, title = {{{Growth of cubic GaN on 3C–SiC/Si (001) nanostructures}}}, doi = {{10.1016/j.jcrysgro.2012.10.011}}, volume = {{378}}, year = {{2012}}, } @article{4114, abstract = {{Two methods to create biomimetic anti-reflection nanostructures in ordinary glass microscope object slides are presented. One technique is based on a nanosphere lithography process combined with physical vapour deposition of nickel and reactive ion etching (RIE). The other uses plasma induced dewetting of a smooth nickel surface. The amount of reflected light was measured and a method to simulate the reflectivity from an atomic force microscopy (AFM) topography scan of the glass surface is presented. The reflectivity for visible light at normal incidence was reduced to 20-50 % of the original value with both methods and the simulation gives results in good agreement to the measurement.}}, author = {{Achtelik, Jörn and Kemper, Ricarda M. and Sievers, Werner and Lindner, Jörg}}, issn = {{1946-4274}}, journal = {{MRS Proceedings}}, location = {{Boston (USA)}}, publisher = {{Cambridge University Press (CUP)}}, title = {{{Self-Organized Nanostructure Formation for Anti-Reflection Glass Surfaces}}}, doi = {{10.1557/opl.2012.491}}, volume = {{1389}}, year = {{2012}}, } @inproceedings{4115, author = {{Brodehl, Christoph and Greulich-Weber, Siegmund and Lindner, Jörg}}, location = {{Paderborn}}, title = {{{Gyrotropic Metamaterials}}}, year = {{2012}}, } @article{4131, abstract = {{We report an anisotropic formation of defects in cubic GaN grown on nano-patterned 3C-SiC/Si (001) by molecular beam epitaxy. Nano-patterning of 3C-SiC/Si (001) is achieved by nanosphere lithography and a reactive ion etching process. Atomic force microscopy and scanning electron microscopy show that the selectivearea- grown cubic GaN nucleates in two structurally different domains, which most probably originate from the substrate. In adjacent domains the formation of defects, especially hexagonal inclusions, is different and leads to two different surface morphologies. The dominant phase within these domains was measured by electron backscatter diffraction. Optical properties were investigated by micro-photoluminescence and cathodoluminescence spectroscopy.}}, author = {{Kemper, R. M. and Häberlen, M. and Schupp, T. and Weinl, M. and Bürger, M. and Ruth, M. and Meier, Cedrik and Niendorf, T. and Maier, H. J. and Lischka, K. and As, D. J. and Lindner, Jörg}}, issn = {{1862-6351}}, journal = {{physica status solidi (c)}}, number = {{3-4}}, pages = {{1028--1031}}, publisher = {{Wiley}}, title = {{{Formation of defects in cubic GaN grown on nano-patterned 3C-SiC (001)}}}, doi = {{10.1002/pssc.201100174}}, volume = {{9}}, year = {{2012}}, } @inproceedings{4133, author = {{Kemper, R.M. and Hiller, L. and Stauden, T. and Pezoldt, J. and Meertens, D. and Luysberg, M. and Tillmann, K. and Riedl, Thomas and As, Donald and Lindner, Jörg}}, location = {{Manchester (UK)}}, title = {{{TEM investigation of GaN thin films grown on nanostructured 3C-SiC/Si(001) substrates}}}, year = {{2012}}, } @inproceedings{4134, author = {{Lindner, Jörg}}, location = {{Warsaw (Poland)}}, title = {{{Nanosphere Lithography: State-of-the-art and Future Directions}}}, year = {{2012}}, } @inproceedings{4135, author = {{Pauly, Johannes and Lindner, Jörg}}, location = {{Warsaw (Poland)}}, title = {{{TEM Characterization of Nickel Nanodot Arrays on Silicon formed by Nanosphere Lithography}}}, year = {{2012}}, } @inproceedings{4138, author = {{Lindner, Jörg}}, location = {{Oberkochen und Jena (online)}}, title = {{{Nanokugellithographie: Grundlagen und Anwendungen}}}, year = {{2012}}, } @inproceedings{4139, author = {{Lindner, Jörg}}, location = {{Leipzig (Germany)}}, title = {{{Nanolithographie von Oberflächen für das Wachstum optoelektronischer Strukturen}}}, year = {{2012}}, } @article{43, author = {{Chen, Xianzhong and Huang, Lingling and Mühlenbernd, Holger and Li, Guixin and Bai, Benfeng and Tan, Qiaofeng and Jin, Guofan and Qiu, Cheng-Wei and Zhang, Shuang and Zentgraf, Thomas}}, issn = {{2041-1723}}, journal = {{Nature Communications}}, publisher = {{Springer Nature}}, title = {{{Dual-polarity plasmonic metalens for visible light}}}, doi = {{10.1038/ncomms2207}}, volume = {{3}}, year = {{2012}}, } @article{4333, author = {{Feneberg, Martin and Röppischer, Marcus and Cobet, Christoph and Esser, Norbert and Schörmann, Jörg and Schupp, Thorsten and As, Donat Josef and Hörich, Florian and Bläsing, Jürgen and Krost, Alois and Goldhahn, Rüdiger}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{15}}, publisher = {{American Physical Society (APS)}}, title = {{{Optical properties of cubic GaN from 1 to 20 eV}}}, doi = {{10.1103/physrevb.85.155207}}, volume = {{85}}, year = {{2012}}, } @inproceedings{4380, abstract = {{The structural and vibrational properties of lithium niobate (LN) – lithium tantalate (LT) mixed crystals (LNT, LiNb1-xTaxO3) are investigated over the whole composition range by first-principles simulations. The crystal volume grows roughly linearly from LT to LN, whereby the lattice parameters a and c show minor deviations from the Vegard behavior between the end compounds, LiNbO3 and LiTaO3. Our calculations in the framework of the density functional theory show the TO1, TO2 and TO4-modes to become harder with increasing Nb concentration. TO3 becomes softer with increasing Nb content, instead. The frequency shifts of the zone center A1-TO phonon modes for crystals with different compositions are found to be as large as 30 cm-1. Raman spectroscopy, which is sensitive to the A1 modes, can be therefore employed to determine the crystal composition.}}, author = {{Sanna, Simone and Riefer, Arthur and Neufeld, Sergej and Schmidt, Wolf Gero and Berth, Gerhard and Widhalm, Alex and Zrenner, Artur}}, booktitle = {{Proceedings of ISAF-ECAPD-PFM 2012}}, keywords = {{Ferroelectrics, Vibrational properties, LiNbO3, LiTaO3, Mixed Crystals}}, location = {{Aveiro, Portugal}}, title = {{{Vibrational fingerprints of LiNbO3-LiTaO3 mixed crystals}}}, year = {{2012}}, } @inbook{4381, abstract = {{Coherent physics and applications of exciton qubits in electric fi eld tunable quantum dot structures are our focus. Excitations with picosecond (ps) laser pulses result in qubit rotations. Using state projection by tunnelling the readout can be performed in quantitative way. As a function of electric fi eld induced detuning Ramsey fringes of a single exciton qubit can be observed and controlled for double pulse excitation. Therefore it is possible to demonstrate voltage controlled qubit manipulations within a wide range of pulse delays. Using fast electric signals, phase-locked to ps-laser pulses, the coherent control of an exciton qubit can be obtained by electric interaction. Such voltage controlled qubit manipulations seem to be essential for new types of optoelectronic quantum gates and novel applications in the fi eld of coherent optoelectronics.}}, author = {{Michaelis de Vasconcellos, Steffen and Gordon, Simon and Mantei, Dirk and Leier, Yves Alexander and Al-Hmoud, M. and Quiring, Wadim and Zrenner, Artur}}, booktitle = {{QUANTUM OPTICS WITH SEMICONDUCTOR NANOSTRUCTURES}}, editor = {{Jahnke, Frank}}, isbn = {{9780857092328 0857092324}}, keywords = {{excitons, quantum bits, coherent manipulation, Ramsey interference, quantum gate}}, pages = {{528--559}}, publisher = {{Woodhead Publishing}}, title = {{{Coherent optoelectronics with quantum dots}}}, year = {{2012}}, } @inbook{5032, author = {{Becker, Jörg and Beverungen, Daniel and Knackstedt, Ralf}}, booktitle = {{Modeling for Decision Support in Network-Based Services: The Application of Quantitative Modeling to Service Science}}, editor = {{Granat Janusz Dolk, Daniel;}}, pages = {{87----117}}, title = {{{A Method for Selectively Designing Modeling Languages for Product-Service Systems}}}, year = {{2012}}, } @inbook{5034, author = {{Becker, Jörg and Knackstedt, Ralf and Beverungen, Daniel and Dietrich, Hanns-Alexander and Breuker, Dominic and Peter Rauer, Hans}}, booktitle = {{Service Engineering --- Management}}, editor = {{Böhmann, Tilo and Knackstedt, Ralf and Marco Leimeister, Jan and Nüttgens, Markus and Thomas, Oliver}}, isbn = {{978-3-8482-2109-7}}, pages = {{127----139}}, title = {{{Ansätze zur methodischen Unterstützung der Konstruktion von Produktivitätsmodellen für die Data Envelopment Analysis --- Entwicklung eines Softwareprototypen zur Umsetzung und Evaluation}}}, year = {{2012}}, } @inbook{5035, author = {{Beverungen, Daniel and Matzner, Martin and Müller, Oliver and Becker, Jörg}}, booktitle = {{Handbook of Service Description}}, editor = {{Barros, Alistair and Oberle, Daniel}}, isbn = {{978-1-4614-1864-1}}, pages = {{19----44}}, title = {{{Product-Service System Approaches}}}, doi = {{10.1007/978-1-4614-1864-1_2}}, year = {{2012}}, } @techreport{5051, author = {{Hegemann, Annika}}, title = {{{Besteuerung von Beteiligungsinvestitionen und Risikoempfindlichkeit – Wie wirkt die Abgeltungssteuer?}}}, volume = {{140}}, year = {{2012}}, } @techreport{5055, author = {{Mehrmann, Annika and Schneider, Georg and Sureth-Sloane, Caren}}, title = {{{Asymmetric Taxation of Profits and Losses and Its Influence on Investment Timing: Paradoxical Effects of Tax Increases}}}, volume = {{134}}, year = {{2012}}, } @article{5056, author = {{Sloane, Peter F. E. and Sureth-Sloane, Caren}}, journal = {{Wirtschaft und Beruf}}, number = {{7-8}}, pages = {{10--13}}, title = {{{Mehr Theorie wagen. Betriebswirtschaftslehre nach Bologna oder Hochschulbildung im Wandel}}}, volume = {{64}}, year = {{2012}}, } @misc{5057, author = {{Sureth-Sloane, Caren}}, booktitle = {{Frankfurter Allgemeine Zeitung}}, number = {{112}}, pages = {{12}}, title = {{{Analytisch und strukturiert denken lernen}}}, year = {{2012}}, } @misc{5060, author = {{Sureth-Sloane, Caren}}, booktitle = {{Frankfurter Allgemeine Zeitung}}, title = {{{Studium nach Bologna: Theorie oder Praxis – ein Scheinwiderspruch?}}}, year = {{2012}}, } @article{5063, author = {{Sureth-Sloane, Caren}}, journal = {{Wirtschaft und Beruf}}, number = {{7-8}}, pages = {{49--51}}, title = {{{Unternehmensführung und interkulturelle Hochschulbildung. Unternehmensführung in Europa - Interkulturelle Fragen}}}, volume = {{64}}, year = {{2012}}, } @inbook{5066, author = {{Sureth-Sloane, Caren}}, booktitle = {{Der Verband der Hochschullehrer für Betriebswirtschaft, Geschichte des VHB und Geschichten zum VHB}}, editor = {{Burr, Wolfgang and Wagenhofer, Alfred}}, publisher = {{Gabler Verlag}}, title = {{{Vorwort. Geschichte des VHB und der BWL: Rückblick und Einblicke}}}, year = {{2012}}, } @misc{5069, author = {{Sureth-Sloane, Caren and zu Knyphausen-Aufseß, Dodo}}, booktitle = {{Frankfurter Allgemeine Zeitung}}, number = {{276}}, pages = {{12}}, title = {{{Welcher BWLer ist ein guter Forscher?}}}, year = {{2012}}, } @article{5116, author = {{Gilroy, Bernard Michael and Kruse, Daniel}}, journal = {{WiSt-Wirtschaftswissenschaftliches Studium}}, number = {{3}}, pages = {{143--150}}, publisher = {{Verlag Franz Vahlen GmbH}}, title = {{{Die Prinzipal-Agent-Theorie als Erklärungsinstrumentarium von Korruption}}}, volume = {{41}}, year = {{2012}}, } @article{5183, author = {{Bodden, Eric and Lam, Patrick and Hendren, Laurie}}, issn = {{0164-0925}}, journal = {{ACM Transactions on Programming Languages and Systems}}, number = {{2}}, pages = {{1--52}}, publisher = {{Association for Computing Machinery (ACM)}}, title = {{{Partially Evaluating Finite-State Runtime Monitors Ahead of Time}}}, doi = {{10.1145/2220365.2220366}}, volume = {{34}}, year = {{2012}}, } @article{5193, abstract = {{We study the predictive ability of individual analyst target price changes for post-event abnormal stock returns within each recommendation category. Although prior studies generally demonstrate the investment value of target prices, we find that target price changes do not cause abnormal returns within each recommendation level. Instead, contradictory analyst signals (e.g., strong buy reiterations with large target price decreases) neutralize each other, whereas confirmatory signals reinforce each other. Further, our analysis reveals that large target price downgrades can be explained by preceding stock price decreases. However, upgrades are not preceded by stock price increases, thereby demonstrating asymmetric analyst behavior when adjusting target prices to stock prices. Our results suggest that investors should treat recommendations with caution when they are issued with large contradictory target price changes. Thus, instead of blindly following a recommendation, investors might put more weight on the change in the corresponding target price and consider transaction costs.}}, author = {{Kanne, Stefan and Klobucnik, Jan and Kreutzmann, Daniel and Sievers, Sönke}}, journal = {{Financial Markets and Portfolio Management (VHB-JOURQUAL 3 Ranking C)}}, keywords = {{Analyst recommendation, Target price, Stock performance, Trading strategy}}, number = {{4}}, pages = {{405--428}}, publisher = {{Springer}}, title = {{{To buy or not to buy? The value of contradictory analyst signals}}}, doi = {{10.1007/s11408-012-0196-z}}, volume = {{26}}, year = {{2012}}, } @article{5196, abstract = {{This study shows how venture capital investors can identify potential biases in multi-year management forecasts before an investment decision and derive significantly more accurate failure predictions. By advancing a cross-sectional projection method developed by prior research and using firm-specific information in financial statements and business plans, we derive benchmarks for management revenue forecasts. With these benchmarks, we estimate forecast errors as an a priori measure of biased expectations. Using this measure for our proprietary dataset on venture-backed start-ups in Germany, we find evidence of substantial upward forecast biases. We uncover that firms with large forecast errors fail significantly more often than do less biased entrepreneurs in years following the investment. Overall, our results highlight the implications of excessive optimism and overconfidence in entrepreneurial environments and emphasize the relevance of accounting information and business plans for venture capital investment decisions. }}, author = {{Mokwa, Christopher Frederik and Sievers, Sönke}}, journal = {{SSRN Electronic Journal}}, keywords = {{Management forecast biases, cross-sectional projection models, venture-backed start-ups, failure prediction, overoptimism, overconfidence}}, title = {{{The Relevance of Biases in Management Forecasts for Failure Prediction in Venture Capital Investments}}}, doi = {{10.2139/ssrn.2100501}}, year = {{2012}}, } @article{5198, abstract = {{This study provides evidence of significant biases in multi-year management forecasts by analyzing a proprietary dataset on venture-backed start-ups in Germany. We find that revenues and expenses are highly overestimated in each of the investigated one- to five-year-ahead planning periods. Furthermore, entrepreneurs underestimate one-year-ahead profit forecasts but clearly overestimate their profit forecasts for all longer-term forecast horizons. Additional analyses reveal that teams with prior management experience issue even more overestimated forecasts and misrepresent their forward-looking information. In contrast, greater asset verifiability and corporate lead investors are associated with lower levels of forecast errors. All key results hold if bias is either measured by traditionally comparing forecasts to ex-post realizations or by using a cross-sectional projection approach based on historical accounting data developed by prior research. }}, author = {{Mokwa, Christopher and Sievers, Sönke}}, journal = {{SSRN Electronic Journal}}, keywords = {{Management forecasts, Forecasting biases, Venture-backed start-ups, Projection methods}}, title = {{{Biases in Management Forecasts of Venture-Backed Start-Ups: Evidence from Internal Due Diligence Documents of VC Investors}}}, doi = {{10.2139/ssrn.1714399}}, year = {{2012}}, } @inbook{5242, author = {{Schmitz, Hendrik and Eibich, P. and Ziebarth, N.R.}}, booktitle = {{DIW Economic Bulletin}}, pages = {{15--24}}, publisher = {{German Institute for Economic Research}}, title = {{{Add-On Premiums Increase Price Transparency: More Policy Holders Switch Health Plans}}}, volume = {{2}}, year = {{2012}}, } @article{5243, author = {{Schmitz, Hendrik and Augurzky, B. and Beivers, A.}}, journal = {{Krankenhaus-Report 2012}}, publisher = {{Schattauer}}, title = {{{Regionale Unterschiede in der stationären Versorgung: Das ländliche Krankenhaus im Fokus}}}, year = {{2012}}, } @article{5494, author = {{Baum, M and Gsell, L and Kabst, Rüdiger}}, journal = {{Die Betriebswirtschaft (ZfB).}}, number = {{3}}, pages = {{235--253}}, title = {{{Determinanten des Employer Branding in deutschen Unternehmen: Ein neoinstitutionalistischer Erklärungsansatz.}}}, volume = {{72}}, year = {{2012}}, } @article{5496, author = {{Baum, M and Kabst, Rüdiger}}, journal = {{Zeitschrift für Betriebswirtschaft (ZfB).}}, pages = {{117--142}}, title = {{{ Die Wirkung von informellen und internetbasierten Rekrutierungskanälen auf den Rekrutierungserfolg: Eine empirische Analyse in kleinen und mittleren Unternehmen.}}}, volume = {{3}}, year = {{2012}}, } @article{5497, author = {{Maekelburger, B and Schwens, C and Kabst, Rüdiger}}, journal = {{Journal of International Business Studies (JIBS).}}, number = {{5}}, pages = {{458--476}}, title = {{{Asset Specificity and Foreign Market Entry Mode Choice of Small and Medium-Sized Enterprises: The Moderating Influence of Knowledge Safeguards and Institutional Safeguards.}}}, volume = {{42}}, year = {{2012}}, } @article{5498, author = {{Eberz, L M and Baum, M and Kabst, Rüdiger}}, journal = {{Zeitschrift für Personalforschung (ZfP).}}, number = {{1}}, pages = {{5--29}}, title = {{{Der Einfluss von Rekrutiererverhaltensweisen auf den Bewerber: Ein mediierter Prozess.}}}, volume = {{26}}, year = {{2012}}, } @article{5508, author = {{Wehner, M C and Kabst, Rüdiger and Meifert, M and Cunz, L M}}, journal = {{Zeitschrift für Betriebswirtschaft (ZfB).}}, number = {{9}}, pages = {{913--933}}, title = {{{Der Personalverantwortliche als strategischer Partner: Persönliche Einstellung oder subjektive Norm?}}}, volume = {{82}}, year = {{2012}}, } @article{5510, author = {{Strohmeier, S and Kabst, Rüdiger}}, journal = {{International Journal of Business Information Systems (IJBIS).}}, number = {{3}}, pages = {{328--342}}, title = {{{Evaluating Major Human Resource Information Systems Design Characteristics: An Empirical Analysis.}}}, volume = {{9}}, year = {{2012}}, } @article{5512, author = {{Frese, M and Bausch, A and Schmidt, P and Rauch, A and Kabst, Rüdiger}}, journal = {{Foundations and Trends in Entrepreneurship. }}, number = {{1}}, pages = {{1--62}}, title = {{{Evidence-based entrepreneurship (EBE): Cumulative science, action principles, and bridging the gap between science and practice.}}}, volume = {{8}}, year = {{2012}}, } @article{5515, author = {{Wehner, M C and Giardini, A and Kabst, Rüdiger}}, journal = {{ Human Resource Management.}}, number = {{4}}, pages = {{601--623}}, title = {{{Graduates’ Reactions to Recruitment Process Outsourcing: A Scenario-Based Study.}}}, volume = {{51}}, year = {{2012}}, } @article{5516, author = {{Eiche, J and Schwens, C and Kabst, Rüdiger}}, journal = {{Zeitschrift für Betriebswirtschaft (ZfB).}}, number = {{3}}, pages = {{143--165}}, title = {{{Greenfield Investment versus Akquisition: Der moderierende Einfluss wahrgenommener institutioneller Unsicherheit bei der Internationalisierung von KMU. }}}, volume = {{82}}, year = {{2012}}, } @article{5518, author = {{Isidor, R and Schwens, C and Kabst, Rüdiger and Hornung, F}}, journal = {{Zeitschrift für Betriebswirtschaft (ZfB).}}, number = {{5}}, pages = {{539--583}}, title = {{{Internationaler Joint Venture Erfolg: Eine Meta-Analyse.}}}, volume = {{82}}, year = {{2012}}, } @article{5519, author = {{Steinmetz, Holger and Isidor, R and Bäuerle, N}}, journal = {{Survey Research Methods}}, number = {{1}}, pages = {{61--75}}, title = {{{Testing the Circular Structure of Human Values: A Meta-Analytical Structural Equation Modelling Approach.}}}, volume = {{6}}, year = {{2012}}, }