TY - CHAP A1 - Meskouris, Konstantin A1 - Gellert, Christoph A1 - Butenweg, Christoph T1 - Neuer Ansatz für die Bemessung von Mauerwerksbauten T2 - Innovationen im konstruktiven Ingenieurbau : Methoden - Materialien - Bauwerke ; Festschrift Professor Hirschfeld / hrsg. von Karl Beucke Y1 - 2010 SP - 217 EP - 224 PB - Bauhaus-Univ. Weimar CY - Weimar ER - TY - JOUR A1 - Butenweg, Christoph A1 - Gellert, Christoph A1 - Schlundt, Andreas T1 - Nichtlinearer Erdbebennachweis von Gebäuden aus Kalksandsteinmauerwerk nach DIN EN 1998 JF - Mauerwerk : European journal of masonry N2 - Die Erdbebensicherheit von Gebäuden aus Kalksandsteinmauerwerk ist aktuell nach DIN 4149 mit linearen Verfahren nachzuweisen. Dies führt in der praktischen Anwendung zu großen Problemen, da selbst traditionell übliche Grundrisse teilweise nicht mehr ohne zusätzliche Maßnahmen nachweisbar sind. Zur Lösung dieser Problematik wurden von der deutschen Mauerwerksindustrie auf nationaler und europäischer Ebene Forschungsprojekte initiiert, deren Ergebnisse in Form von statisch nichtlinearen Verfahren Eingang in den Nationalen Anhang zur DIN EN 1998-1 [12] gefunden haben. Mit den Verfahren wird die Nachweissituation zukünftig grundlegend verbessert, da mit diesen die Tragwerksreserven wesentlich besser ausgenutzt werden können. Im Folgenden wird die Anwendung der Verfahren am Beispiel einer Reihenhauszeile aus Kalksandsteinmauerwerk demonstriert. Der Nachweis der Reihenhäuser wurde im Rahmen einer Zustimmung im Einzelfall, die vom Bundesverband Kalksandsteinindustrie eV in Hannover koordiniert wurde, durch unabhängige Gutachter und die Bauaufsicht eingehend geprüft und für richtig befunden. Die Durchführung des Nachweises erfolgte auf Grundlage eines an der RWTH Aachen entwickelten neuen Nachweiskonzeptes. Die baupraktische Anwendbarkeit und einfache Nachvollziehbarkeit dieses Konzepts ist durch eine softwaretechnische Umsetzung sichergestellt. Y1 - 2010 U6 - https://doi.org/10.1002/dama.201000463 SN - 1432-3427 VL - 14 IS - 3 SP - 120 EP - 125 PB - Ernst & Sohn CY - Berlin ER - TY - JOUR A1 - Pieper, Martin A1 - Klein, Peter T1 - Numerical solution of the heat equation with non-linear, time derivative-dependent source term JF - International Journal for Numerical Methods in Engineering N2 - The mathematical modeling of heat conduction with adsorption effects in coated metal structures yields the heat equation with piecewise smooth coefficients and a new kind of source term. This term is special, because it is non-linear and furthermore depends on a time derivative. In our approach we reformulated this as a new problem for the usual heat equation, without source term but with a new non-linear coefficient. We gave an existence and uniqueness proof for the weak solution of the reformulated problem. To obtain a numerical solution, we developed a semi-implicit and a fully implicit finite volume method. We compared these two methods theoretically as well as numerically. Finally, as practical application, we simulated the heat conduction in coated aluminum fibers with adsorption in the zeolite coating. Copyright © 2010 John Wiley & Sons, Ltd. Y1 - 2010 U6 - https://doi.org/10.1002/nme.2937 SN - 0029-5981 VL - 84 IS - 10 SP - 1205 EP - 1221 PB - Wiley CY - Chichester ER - TY - JOUR A1 - Kern, Alexander A1 - Klöters, Georg A1 - Pferdemenges, Jörg T1 - Optimised protection against lightning for the signalling and safety systems of level crossings on non-electrified railway lines JF - RTR : European Rail Technology Review Y1 - 2010 SN - 0079-9548 VL - 50 IS - 2 PB - DVV Media Group CY - Hamburg ER - TY - JOUR A1 - Fleischhaker, Robert A1 - Evers, Jörg A1 - Dey, Tarak N. T1 - Phase modulation induced by cooperative effects in electromagnetically induced transparency JF - Physical Review A - Atomic, molecular, and optical physics N2 - We analyze the influence of dipole-dipole interactions in an electromagnetically induced transparency set up for a density at the onset of cooperative effects. To this end, we include mean-field models for the influence of local-field corrections and radiation trapping into our calculation. We show both analytically and numerically that the polarization contribution to the local field strongly modulates the phase of a weak pulse. We give an intuitive explanation for this local-field-induced phase modulation and demonstrate that it distinctively differs from the nonlinear self-phase-modulation that a strong pulse experiences in a Kerr medium. Y1 - 2010 U6 - https://doi.org/10.1103/PhysRevA.82.013815 SN - 1050-2947 VL - 82 IS - 1 PB - AIP Publishing CY - Melville, NY ER - TY - JOUR A1 - Kern, Alexander A1 - Schelthoff, Christof A1 - Mathieu, Moritz T1 - Probability of lightning strikes to air-terminations of structures using the electro-geometrical model theory and the statistics of lightning current parameters N2 - Planning the air-terminations for a structure to be protected the use of the rolling-sphere method (electro-geometrical model) is the best way from the physics of lightning point-of-view. Therefore, international standards prefer this method. However, using the rolling-sphere method only results in possible point-of-strikes on a structure without giving information about the probability of strikes at the individual points compared to others. KW - atmospheric modeling KW - probability distribution KW - lightning protection KW - standards KW - planning Y1 - 2010 SN - 978-88-905519-0-1 U6 - https://doi.org/10.1109/ICLP.2010.7845757 N1 - 2010 30th International Conference on Lightning Protection (ICLP), 13-17 Sept. 2010, Cagliari, Italy SP - 750-1 EP - 750-8 PB - IEEE CY - New York ER - TY - JOUR A1 - Vogt, C. A1 - Mottaghy, Darius A1 - Wolf, A. A1 - Rath, V. A1 - Pechnig, R. A1 - Clauser, C. T1 - Reducing temperature uncertainties by stochastic geothermal reservoir modelling JF - Geophysical Journal International N2 - Quantifying and minimizing uncertainty is vital for simulating technically and economically successful geothermal reservoirs. To this end, we apply a stochastic modelling sequence, a Monte Carlo study, based on (i) creating an ensemble of possible realizations of a reservoir model, (ii) forward simulation of fluid flow and heat transport, and (iii) constraining post-processing using observed state variables. To generate the ensemble, we use the stochastic algorithm of Sequential Gaussian Simulation and test its potential fitting rock properties, such as thermal conductivity and permeability, of a synthetic reference model and—performing a corresponding forward simulation—state variables such as temperature. The ensemble yields probability distributions of rock properties and state variables at any location inside the reservoir. In addition, we perform a constraining post-processing in order to minimize the uncertainty of the obtained distributions by conditioning the ensemble to observed state variables, in this case temperature. This constraining post-processing works particularly well on systems dominated by fluid flow. The stochastic modelling sequence is applied to a large, steady-state 3-D heat flow model of a reservoir in The Hague, Netherlands. The spatial thermal conductivity distribution is simulated stochastically based on available logging data. Errors of bottom-hole temperatures provide thresholds for the constraining technique performed afterwards. This reduce the temperature uncertainty for the proposed target location significantly from 25 to 12 K (full distribution width) in a depth of 2300 m. Assuming a Gaussian shape of the temperature distribution, the standard deviation is 1.8 K. To allow a more comprehensive approach to quantify uncertainty, we also implement the stochastic simulation of boundary conditions and demonstrate this for the basal specific heat flow in the reservoir of The Hague. As expected, this results in a larger distribution width and hence, a larger, but more realistic uncertainty estimate. However, applying the constraining post-processing the uncertainty is again reduced to the level of the post-processing without stochastic boundary simulation. Thus, constraining post-processing is a suitable tool for reducing uncertainty estimates by observed state variables. Y1 - 2010 U6 - https://doi.org/10.1111/j.1365-246X.2009.04498.x SN - 1365-246X VL - 181 IS - 1 SP - 321 EP - 333 PB - Oxford University Press CY - Oxford ER - TY - CHAP A1 - Reindl, Lukas A1 - Park, Jin A1 - Norda, Hannah A1 - Butenweg, Christoph T1 - Seismic design of masonry walls subject to out-of-plane bending T2 - Proceedings of the Tenth International Conference on Computational Structures Technology : Valencia, Spain, 14 - 17 September 2010 / organised in association with: Universidad Politecnica de Valencia ... Ed. by B. H. V. Topping ... Y1 - 2010 SN - 978-1-905088-36-2 U6 - https://doi.org/10.4203/ccp.93.348 SP - Paper 348 PB - Civil-Comp Press CY - Kippen ER - TY - CHAP A1 - Gellert, Christoph A1 - Park, Jin A1 - Butenweg, Christoph T1 - Seismic safety verification of masonry structures T2 - Proceedings of the Eight International Masonry Conference : held in Dresden from 4th to 7th of July 2010 / [International Masonry Society ; Technische Universität Dresden]. Ed. by: Wolfram Jäger ... Volume 1. (Masonry / International Masonry Society Special Publication ; 11) Y1 - 2010 SN - 978-3-00-031381-3 SP - 813 EP - 822 PB - ARGE 8IMC Dresden CY - Radebeul ER - TY - CHAP A1 - Meskouris, Konstantin A1 - Holtschoppen, Britta A1 - Butenweg, Christoph A1 - Park, Jin T1 - Seismische Auslegung von Silo- und Tankbauwerken T2 - Festschrift zum 60. Geburtstag von Univ.-Prof. Dr.-Ing. Ingbert Mangerig. (Berichte aus dem konstruktiven Ingenieurbau ; 2010,6) Y1 - 2010 SP - 215 EP - 224 PB - Univ. der Bundeswehr CY - Neubiberg ER - TY - JOUR A1 - Kern, Alexander A1 - Frentzel, Ralf A1 - Behrens, Jörg T1 - Simulation of the transient voltages in the auxiliary power network of a large power plant in case of a direct lightning strike to the high-voltage overhead transmission line N2 - Large power plants can be endangered by lightning strikes with possible consequences regarding their safety and availability. A special scenario is a lightning strike to the HV overhead transmission line close to the power plant's connection to the power grid. If then additionally a so-called shielding failure of the overhead ground wire on top of the overhead transmission line is assumed, i.e. the lightning strikes directly into a phase conductor, this is an extreme electromagnetic disturbance. The paper deals with the numerical simulation of such a lightning strike and the consequences on the components of the power plant's auxiliary power network connected to different voltage levels. KW - power generation KW - surges KW - conductors KW - arresters KW - power transmission lines KW - lightning Y1 - 2010 SN - 978-88-905519-0-1 U6 - https://doi.org/10.1109/ICLP.2010.7845756 N1 - 2010 30th International Conference on Lightning Protection (ICLP), 13-17 Sept. 2010, Cagliari, Italy SP - 749-1 EP - 749-7 PB - IEEE CY - New York ER - TY - JOUR A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard T1 - Solar tower power plant in Germany and future perspectives of the development of the technology in Greece and Cyprus JF - Renewable Energy N2 - Since the 80s power production with solar thermal power plants has been a way to substitute fossil fuels. By concentrating direct solar radiation from heliostats very high temperatures of a thermal fluid can be reached. The resulting heat is converted to mechanical energy in a steam cycle which generates electricity. High efficiencies and fast start-up are reached by using air as a heat medium, as well as using porous ceramic materials as solar receiver of the concentrated sunlight. In Germany the construction of a 1.5 MWe solar tower power plant began in 2008. It is operational since December 2008 and started production of electricity in the spring of 2009. In Greece and Cyprus, countries with high solar potential, the development of this competitive solar thermal technology is imperative, since it has already been implemented in other Mediterranean countries. Y1 - 2010 U6 - https://doi.org/10.1016/j.renene.2009.11.003 SN - 0960-1481 VL - 35 IS - 7 SP - 1352 EP - 1356 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Alexopoulos, Spiros A1 - Hoffschmidt, Bernhard T1 - Solarthermische Kraftwerke mit thermischen Speichern JF - Chemie Ingenieur Technik N2 - Solarthermische Kraftwerke stellen eine bedeutende Technologieoption für einen nachhaltigen Energiemix der Zukunft dar. Sie konzentrieren die Strahlung der Sonne, erzeugen Wärme und wandeln diese mit konventioneller Kraftwerkstechnik in Strom um. Die Wärme kann auch gespeichert werden, so dass der Betrieb während des Durchzugs von Wolken möglich ist und bis in die Abendstunden hinein verlängert werden kann. Zu den solarthermischen Kraftwerken gehören neben der Parabolrinne und dem Solarturm der Fresnel-Kollektor und die Dish-Stirling-Systeme. Im Zuge einer späteren Vergrößerung des Solarfeldes von Solarkraftwerken kann mithilfe von thermischen Energiespeichern die solare Energieerzeugung bei gleichbleibender Kraftwerksleistung sukzessiv bis um den Faktor 3 erweitert werden. Es besteht so die Möglichkeit einer massiven Substitution von fossilen Brennstoffen.Bei den ersten solarthermischen Speichern für die SEGS-Parabolrinnekraftwerke wurde Öl als Speichermedium eingesetzt. Ein weiteres Speichermedium ist Salzschmelze, die im Andasol-1-Projekt in Spanien sowie bei Solarturmkraftwerken eingesetzt wird. Beton ist ein weiteres mögliches Speichermaterial für Parabolrinnensysteme. Eine weitere Alternative bei einem Solarturmkraftwerk mit Luft als Wärmeträgermedium ist die Verwendung von keramischen Feuerfestmaterialien in Form von Schüttungen oder stapelbaren, porösen Elementen. In Jülich wurde das weltweit erste solarthermische Turmkraftwerk mit einer Leistung von 1,5 MWe, das Luft als Wärmeträgermedium einsetzt und einen solchen Speicher verwendet, gebaut. Y1 - 2010 SN - 1522-2640 U6 - https://doi.org/10.1002/cite.201050678 N1 - Special Issue: ProcessNet-Jahrestagung 2010 und 28. Jahrestagung der Biotechnologen VL - 82 IS - 9 SP - 1606 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Goldbach, Daniel A1 - Ament, Christoph ED - Scharff, Peter T1 - Stabilized reversing with vehicle trailer combinations T2 - Crossing borders within the ABC : automation, biomedical engineering and computer science; proceedings; 55. IWK Internationales Wissenschaftliches Kolloquium; 13 - 17 September 2010, Ilmenau Y1 - 2010 SN - 978-3-938843-53-6 SP - 352 EP - 357 PB - Verl. ISLE CY - Ilmenau ER - TY - BOOK A1 - Hoffschmidt, Bernhard A1 - Lan, Marco A1 - Fricke, Barbara A1 - Anthrakidis, Anette A1 - Peter, Stefan T1 - Struktur und Dynamik einer Stromversorgung mit einem hohen Anteil erneuerbarer Energieerzeuger. Kurzbezeichnung: Energiestudie. Schlussbericht Y1 - 2010 N1 - BMU-Forschungsbericht. Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit / 2010 / 20110602205 PB - Solar-Institut, FH Aachen CY - Jülich ER - TY - JOUR A1 - Geimer, Konstantin A1 - Sauerborn, Markus A1 - Hoffschmidt, Bernhard A1 - Schmitz, Mark A1 - Göttsche, Joachim T1 - Test facility for absorber specimens of solar tower power plants JF - Advances in Science and Technology N2 - The Solar-Institute Jülich (SIJ) has initiated the construction of the first and only German solar tower power plant and is now involved in the accompanying research. The power plant for experimental and demonstration purposes in the town of Jülich started supplying electric energy in the beginning of 2008. The central receiver plant features as central innovation an open volumetric receiver, consisting of porous ceramic elements that simultaneously absorb the concentrated sunlight and transfer the heat to ambient air passing through the pores so that an average temperature of 680°C is reached. The subsequent steam cycle generates up to 1.5 MWe. A main field of research at the SIJ is the optimization of the absorber structures. To analyze the capability of new absorber specimens a special test facility was developed and set up in the laboratory. A high-performance near-infrared radiator offers for single test samples a variable and repeatable beam with a power of up to 320 kW/m² peak. The temperatures achieved on the absorber surface can reach more than 1000°C. To suck ambient air through the open absorber - like on the tower - it is mounted on a special blower system. An overview about the test facility and some recent results will be presented. Y1 - 2010 U6 - https://doi.org/10.4028/www.scientific.net/AST.74.266 N1 - 5th Forum on New Materials : CIMTEC 2010, Montecatini Terme, Italy 13-18 June 2010. Part C VL - 74 SP - 266 EP - 271 PB - Trans Tech Publications CY - Baech ER - TY - CHAP A1 - Park, Jin A1 - Butenweg, Christoph A1 - Reindl, Lukas T1 - Untersuchung der Eignung von Ankerschienensystemen unter Erdbebeneinwirkungen T2 - Conference proceedings / ANSYS Conference & 28th CADFEM Users´ Meeting 2010 : 3. - 5. November 2010, Eurogess Aachen / CADFEM; ANSYS Y1 - 2010 SN - 3-937523-07-3 SP - Dokument 2.11.1 PB - CADFEM [u.a.] CY - Grafing ER -