@book{DonnerCserSchwarzetal.2004, author = {Donner, Reik Volker and Cser, Adrienn and Schwarz, Udo and Otto, Andreas H. and Feudel, Ulrike}, title = {An approach to a process model of laser beam melt ablation using methods of linear and non-linear data analysis}, isbn = {3-527-40430-9}, year = {2004}, abstract = {As a non-contact process laser beam melt ablation offers several advantages compared to conventional processing mechanisms. During ablation the surface of the workpiece is molten by the energy of a CO2-laser beam, this melt is then driven out by the impulse of an additional process gas. Although the idea behind laser beam melt ablation is rather simple, the process itself has a major limitation in practical applications: with increasing ablation rate surface quality of the workpiece processed declines rapidly. With different ablation rates different surface structures can be distinguished, which can be characterised by suitable surface parameters. The corresponding regimes of pattern formation are found in linear and non-linear statistical properties of the recorded process emissions as well. While the ablation rate can be represented in terms of the line-energy, this parameter does not provide sufficient information about the full behaviour of the system. The dynamics of the system is dominated by oscillations due to the laser cycle but includes some periodically driven non-linear processes as well. Upon the basis of the measured time series, a corresponding model is developed. The deeper understanding of the process can be used to develop strategies for a process control.}, language = {en} } @book{DonnerCserSchwarzetal.2003, author = {Donner, Reik Volker and Cser, Adrienn and Schwarz, Udo and Otto, Andreas H. and Feudel, Ulrike}, title = {An approach to a process model of laser beam melt ablation using methods of linear and non-linear data analysis}, isbn = {3-928921-88-6}, year = {2003}, abstract = {As a non-contact process laser beam melt ablation offers several advantages compared to conventional processing mechanisms. During ablation the surface of the workpiece is molten by the energy of a CO2-laser beam, this melt is then driven out by the impulse of an additional process gas. Although the idea behind laser beam melt ablation is rather simple, the process itself has a major limitation in practical applications: with increasing ablation rate surface quality of the workpiece processed declines rapidly. With different ablation rates different surface structures can be distinguished, which can be characterised by suitable surface parameters. The corresponding regimes of pattern formation are found in linear and non-linear statistical properties of the recorded process emissions as well. While the ablation rate can be represented in terms of the line-energy, this parameter does not provide sufficient information about the full behaviour of the system. The dynamics of the system is dominated by oscillations due to the laser cycle but includes some periodically driven non-linear processes as well. Upon the basis of the measured time series, a corresponding model is developed. The deeper understanding of the process can be used to develop strategies for a process control.}, language = {en} } @article{CserDonnerSchwarzetal.2002, author = {Cser, Adrienn and Donner, Reik Volker and Schwarz, Udo and Otto, Andreas H. and Geiger, M. and Feudel, Ulrike}, title = {Towards a better understanding of laser beam melt ablation using methods of statistical analysis}, isbn = {88-87030-44-8}, year = {2002}, abstract = {Laser beam melt ablation, as a contact free machining process, offers several advantages compared to conventional processing mechanisms. Although the idea behind it is rather simple, the process has a major limitation: with increasing ablation rate surface quality of the workpiece processed declines rapidly. The structures observed show a clear dependence of the line energy. In dependence of this parameter several regimes of the process have been separated. These are clearly distinguishable as well in the surfaces obtained as in the signals gained by the measurement of the process emissions which is the observed quantity chosen.}, language = {en} } @book{KargSchopperPaschkeetal.2007, author = {Karg, Detlef and Schopper, Franz and Paschke, Ralph and Meyer, Michael and Ackermann, Irmgard and Baxmann, Matthias and Buchinger, Marie-Luise and Cante, Marcus and Dreger, Hans-Joachim and Gramlich, Sybille and Schwarz, Ulrike and H{\"u}bener, Dieter and Metzler, Matthias and Niemann, Alexander and Rohowski, Ilona and Senst, Ingetraud and Groß, Wera}, title = {Denkmalentdeckungen}, editor = {Brandenburgisches Landesamt f{\"u}r Denkmalpflege und Arch{\"a}ologisches Landesmuseum,}, edition = {1200}, publisher = {Wernersche Verlagsgesellschaft}, address = {Worms}, isbn = {978-3-88462-244-5}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-72290}, publisher = {Universit{\"a}t Potsdam}, pages = {288}, year = {2007}, abstract = {»Wenn du reisen willst, mußt du die Geschichte dieses Landes kennen und lieben. Das ist ganz unerl{\"a}ßlich. [...] Wag' es getrost und du wirst es nicht bereuen. Eigent{\"u}mliche Freuden und Gen{\"u}sse werden dich begleiten. Du wirst Entdeckungen machen, denn {\"u}berall wohin du kommst, wirst du, vom Touristenstandpunkt aus, eintreten wie in ›jungfr{\"a}uliches Land‹. Du wirst Klosterruinen begegnen, von deren Existenz h{\"o}chstens die n{\"a}chste Stadt eine leise Kenntnis hatte; du wirst inmitten alter Dorfkirchen, deren zerbr{\"o}ckelter Schindelturm nur auf Elend deutete, große Wandbilder oder in den treppenlosen Gr{\"u}ften reiche Kupfers{\"a}rge mit Kruzifix und vergoldeten Wappenschildern finden; du wirst Schlachtfelder {\"u}berschreiten, Wendenkirchh{\"o}fe, Heidengr{\"a}ber, von denen die Menschen nichts mehr wissen.« Die in diesem Bildband gesammelten »Denkmalentdeckungen« verstehen sich als Einladung zu einer Reise durch das Land Brandenburg. Theodor Fontane hatte f{\"u}r ein solches Unternehmen genau den richtigen Blick, als er in seinen »Wanderungen durch die Mark Brandenburg« 1864 diese S{\"a}tze schrieb. Auch heute noch sollten wir seiner Anregung zu Begegnungen mit der Geschichte und der Kunstgeschichte des Landes folgen, die uns im Dialog der Kulturen und der Zeiten eine Standortbestimmung in der Gegenwart und eine Orientierung f{\"u}r die Zukunft zugleich bietet.}, language = {de} } @article{FeudelJansenKurthsetal.1997, author = {Feudel, Ulrike and Jansen, Wolfgang and Kurths, J{\"u}rgen and Schwarz, Udo and Voss, Henning U.}, title = {Solar variability : simple models and proxy data}, isbn = {4-274-90187-4}, year = {1997}, language = {en} } @article{BubeNetoDonneretal.2006, author = {Bube, Kevin and Neto, Camilo Rodrigues and Donner, Reik Volker and Schwarz, Udo and Feudel, Ulrike}, title = {Linear and nonlinear characterization of surfaces from a laser beam melt ablation process}, issn = {0022-3727}, doi = {10.1088/0022-3727/39/7/011}, year = {2006}, abstract = {We apply linear and nonlinear methods to study the properties of surfaces generated by a laser beam melt ablation process. As a result we present a characterization and ordering of the surfaces depending on the adjusted process parameters. Our findings give some insight into the performance of two widely applied multifractal analysis methods-the detrended fluctuation analysis and the wavelet transform modulus maxima method-on short real world data}, language = {en} } @article{CserDonnerSchwarzetal.2001, author = {Cser, Adrienn and Donner, Reik Volker and Schwarz, Udo and Feudel, Ulrike and Otto, Andreas H.}, title = {Statistical parameters of a control strategy of laser beam melt ablation}, year = {2001}, abstract = {Laser beam melt ablation - a contact-free machining process - offers several advantages compared to conventional processing mechanisms: there exists no tool wear and even extremely hard or brittle materials can be processed. During ablation the workpiece is molten by a CO2-laser beam, this melt is then driven out by the impulse of a process gas. The idea behind laser ablation is rather simple, but it has a major limitation in practical applications: with increasing ablation rates surface quality of the workpiece processed declines rapidly. At high ablation rates, depending on the process parameters different periodic-like structures can be observed on the ablated surface. These structures show a dependence on the line energy, which has been identified as a fundamental control parameter. In dependence on this parameter several regimes with different behaviours of the process have been separated. These regimes are distinguishable as well in the surfaces obtained as in the signals gained by the measurement of the process emissions. Further aim is to identify the different modes of the system and reach a deeper understanding of the dynamics of the molten material in order to understand the formation of these surface structures. With this it should be possible to influence the system in the direction of avoiding structure formation even at high ablation rates. Relying on the results on-line monitoring and control of the process should be studied.}, language = {en} } @article{JobstKnoblochLeitneretal.2006, author = {Jobst, Anne and Knobloch, Eberhard and Leitner, Ulrike and Mikosch, Regina and Pieper, Herbert and Schwarz, Ingo and Werner, Petra and Werther, Romy}, title = {Margot Faak zum 80. Geburtstag}, volume = {VII}, number = {13}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1617-5239}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-35594}, pages = {8 -- 9}, year = {2006}, language = {de} } @misc{JobstKnoblochLeitneretal.2006, author = {Jobst, Anne and Knobloch, Eberhard and Leitner, Ulrike and Mikosch, Regina and Pieper, Herbert and Schwarz, Ingo and Bourguet, Marie-No{\"e}lle and Ette, Ottmar and Suckow, Christian and Thiemer-Sachse, Ursula and Faak, Margot}, title = {HiN : Alexander von Humboldt im Netz = Festschrift f{\"u}r Margot Faak zu Ehren ihres 80. Geburtstages}, volume = {VII}, number = {13}, editor = {Ette, Ottmar and Knobloch, Eberhard}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1617-5239}, doi = {10.18443/hinvol7iss132006}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-35709}, pages = {115}, year = {2006}, abstract = {Inhalt: - Die Mitarbeiter der Avh-Forschungsstelle: Margot Faak zum 80. Geburtstag - Marie-No{\"e}lle Bourguet: La fabrique du savoir. Essai sur les carnets de voyage d'Alexander von Humboldt - Ottmar Ette: Unterwegs zu einer Weltwissenschaft? Alexander von Humboldts Weltbegriffe und die transarealen Studien - Eberhard Knobloch: Erkundung und Erforschung - Alexander von Humboldts Amerikareise - Herbert Pieper: Die Geognosie der Vulkane - Christian Suckow: Prinz Humboldt - Ursula Thiemer-Sachse: !'Qu{\´e} arte es comprender el arte ...! La visi{\´o}n del arte ind{\´i}gena de Am{\´e}rica por Alejandro de Humboldt - Margot Faak: G. W. Leibniz im Urteil Alexander von Humboldts - Regina Mikosch, Ingo Schwarz: Bibliographie zu Margot Faak}, language = {mul} } @misc{KnoblochKoelbelSauerweinetal.2008, author = {Knobloch, Eberhard and K{\"o}lbel, Bernd and Sauerwein, Martin and Sauerwein, Katrin and K{\"o}lbel, Steffen and Buckow, Cathleen and Leitner, Ulrike and Schwarz, Ingo and Suckow, Christian and Werner, Petra and Pieper, Herbert}, title = {HiN : Alexander von Humboldt im Netz = Herbert Pieper zum 65. Geburtstag}, volume = {IX}, number = {16}, editor = {Ette, Ottmar and Knobloch, Eberhard}, publisher = {Universit{\"a}tsverlag Potsdam}, address = {Potsdam}, issn = {1617-5239}, doi = {10.18443/hinvol9iss162008}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-42246}, pages = {65}, year = {2008}, abstract = {Herbert Pieper zum 65. Geburtstag Inhalt: - Eberhard Knobloch: Herbert Pieper zum 65. Geburtstag. Ein R{\"u}ckblick - Bernd K{\"o}lbel, Martin Sauerwein, Katrin Sauerwein, Steffen K{\"o}lbel, Cathleen Buckow: Das Fragment des englischen Tagebuches von Alexander von Humboldt - Ulrike Leitner: Humboldt, Cotta, Ritter. Eine Miszelle {\"u}ber die Arbeit an einer Edition - Ingo Schwarz: "da ich mich lebhaft f{\"u}r sein Schiksal im Neuen Continent interessire". A. v. Humboldt als F{\"o}rderer Oscar M. Liebers - Christian Suckow: Humboldts spanische Option 1830. Eine Nachlese - Petra Werner: Bemerkungen zu Alexander von Humboldts Russland-Tagebuch - Herbert Pieper Alexander von Humboldts Wahl in die Akademie der Wissenschaften zu Berlin - Publikationen von Herbert Pieper [Bibliographie]}, language = {de} }