TY - BOOK A1 - Pettrak, Jürgen T1 - Nutzung nachwachsender Rohstoffe bei der Herstellung thermoplastischer Elastomere aus Folgeprodukten der Olefinmetathese Y1 - 2014 SN - 978-3-942742-35-1 N1 - Nachwachsende Rohstoffe in Forschung und Praxis ; Bd. 4 PB - Attenkofer CY - Straubing ER - TY - JOUR A1 - Fiedler, Thomas M. A1 - Ladd, Mark E. A1 - Bitz, Andreas T1 - RF safety assessment of a bilateral four-channel transmit/receive 7 Tesla breast coil: SAR versus temperature limits JF - Medical Physics Y1 - 2017 U6 - https://doi.org/10.1002/mp.12034 N1 - This article is corrected by: Errata: Erratum: “RF safety assessment of a bilateral four-channel transmit/receive 7 Tesla breast coil: SAR versus tissue temperature limits” [Med. Phys. 44(1), 143–157 (2017)] Volume 44, Issue 2, 772 VL - 44 IS - 1 SP - 143 EP - 157 ER - TY - JOUR A1 - Fiedler, Thomas M. A1 - Ladd, Mark E. A1 - Clemens, Markus A1 - Bitz, Andreas T1 - Safety of subjects during radiofrequency exposure in ultra-high-field magnetic resonance imaging JF - IEEE Letters on Electromagnetic Compatibility Practice and Applications N2 - Magnetic resonance imaging (MRI) is one of the most important medical imaging techniques. Since the introduction of MRI in the mid-1980s, there has been a continuous trend toward higher static magnetic fields to obtain i.a. a higher signal-to-noise ratio. The step toward ultra-high-field (UHF) MRI at 7 Tesla and higher, however, creates several challenges regarding the homogeneity of the spin excitation RF transmit field and the RF exposure of the subject. In UHF MRI systems, the wavelength of the RF field is in the range of the diameter of the human body, which can result in inhomogeneous spin excitation and local SAR hotspots. To optimize the homogeneity in a region of interest, UHF MRI systems use parallel transmit systems with multiple transmit antennas and time-dependent modulation of the RF signal in the individual transmit channels. Furthermore, SAR increases with increasing field strength, while the SAR limits remain unchanged. Two different approaches to generate the RF transmit field in UHF systems using antenna arrays close and remote to the body are investigated in this letter. Achievable imaging performance is evaluated compared to typical clinical RF transmit systems at lower field strength. The evaluation has been performed under consideration of RF exposure based on local SAR and tissue temperature. Furthermore, results for thermal dose as an alternative RF exposure metric are presented. Y1 - 2020 SN - 2637-6423 U6 - https://doi.org/10.1109/LEMCPA.2020.3029747 VL - 2 IS - 3 SP - 1 EP - 8 PB - IEEE CY - New York, NY ER - TY - RPRT A1 - Ghinaiya, Jagdishkumar A1 - Lehmann, Thomas Martin A1 - Göttsche, Joachim T1 - LOCAL+ – ein kreislauffähiger Holzmodulbau mit nachhaltigem Energie- und Wohnraumkonzept T2 - Bauphysik N2 - Mit dem Beitrag des Teams der FH Aachen zum SDE 21/22 wird im Projekt LOCAL+ ein kreislauffähiger Holzmodulbau mit einem innovativen Wohnraumkonzept geplant und umgesetzt. Ziel dieses Konzeptes ist die Verringerung des stetig steigenden Wohnflächenbedarfs durch ein Raum-in-Raum Konzept. Gebäudetechnisch wird in dem Projekt nicht nur das Einzelgebäude betrachtet, sondern unter Berücksichtigung des Gebäudebestandes wird für das Quartier ein innovatives und nachhaltiges Energiekonzept entwickelt. Ein zentrales Wasserstoffsystem ist für ein Quartier geplant, um den Stromverbrauch aus dem Netz im Winter zu reduzieren. Zentraler Bestandteil des TGA-Konzepts ist ein unterirdischer Eisspeicher, eine PVT und eine Wärmepumpe mit intelligenter Regelstrategie. Ein Teil des neuen Gebäudes (Design Challenge DC) wird in Wuppertal als Hausdemonstrationseinheit (HDU) präsentiert. Eine hygrothermische Simulation der HDU wurde mit der WUFI-Software durchgeführt. Da im Innenraum Lehmmodule und -platten als Feuchtigkeitspuffer verwendet werden, spielen die Themen Feuchtigkeit, Holzfäule und Schimmelwachstum eine wichtige Rolle. KW - Energiekonzept KW - Gesamtwassergehalt KW - Feuchtigkeit KW - Verdunstungskälte KW - energy concept Y1 - 2022 U6 - https://doi.org/10.1002/bapi.202200010 SN - 0171-5445 (Print) SN - 1437-0980 (Online) VL - 44 IS - 3 SP - 136 EP - 142 PB - Ernst & Sohn CY - Hoboken ER - TY - BOOK A1 - Scholl, Ingrid ED - Lehmann, Thomas Martin ED - Spitzer, Klaus T1 - Bildverarbeitung für die Medizin : Algorithmen - Systeme - Anwendungen ; proceedings des Aachener Workshops am 8. und 9. November 1996 / Institut für Medizinische Informatik und Biometrie der RWTH Aachen. Hrsg. von Thomas Lehmann ; Ingrid Scholl ; Klaus Spitzer Y1 - 1996 SN - 3-86073-519-5 PB - Verlag der Augustinus-Buchhandlung CY - Aachen ER - TY - JOUR A1 - Blome, Hans-Joachim A1 - Mashhoon, Bahram T1 - Quasi-normal oscillations of a Schwarzschild black hole JF - Physics Letters A. 100 (1984), H. 5 Y1 - 1984 SN - 0375-9601 SP - 231 EP - 234 ER - TY - JOUR A1 - Wollert, Jörg A1 - Fiedler, Jörg A1 - Stockmann, T. T1 - Automatisieren mit dem PC : was der Personal Computer kann und wo er passen muss JF - Elektronik : Fachmedium für industrielle Anwender und Entwickler Y1 - 1994 SN - 0013-5658 IS - Nr. 6 SP - 76 EP - 82 ER - TY - JOUR A1 - Vögele, Stefan A1 - Josyabhatla, Vishnu Teja A1 - Ball, Christopher Stephen A1 - Rhoden, Imke A1 - Grajewski, Matthias A1 - Rübbelke, Dirk A1 - Kuckshinrichs, Wilhelm T1 - Robust assessment of energy scenarios from stakeholders' perspectives JF - Energy N2 - Using scenarios is vital in identifying and specifying measures for successfully transforming the energy system. Such transformations can be particularly challenging and require the support of a broader set of stakeholders. Otherwise, there will be opposition in the form of reluctance to adopt the necessary technologies. Usually, processes for considering stakeholders' perspectives are very time-consuming and costly. In particular, there are uncertainties about how to deal with modifications in the scenarios. In principle, new consulting processes will be required. In our study, we show how multi-criteria decision analysis can be used to analyze stakeholders' attitudes toward transition paths. Since stakeholders differ regarding their preferences and time horizons, we employ a multi-criteria decision analysis approach to identify which stakeholders will support or oppose a transition path. We provide a flexible template for analyzing stakeholder preferences toward transition paths. This flexibility comes from the fact that our multi-criteria decision aid-based approach does not involve intensive empirical work with stakeholders. Instead, it involves subjecting assumptions to robustness analysis, which can help identify options to influence stakeholders' attitudes toward transitions. Y1 - 2023 U6 - https://doi.org/10.1016/j.energy.2023.128326 SN - 1873-6785 (Online) SN - 0360-5442 (Print) IS - In Press, Article 128326 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Göttsche, Joachim A1 - Hoffschmidt, Bernhard A1 - Schmitz, Stefan A1 - Sauerborn, Markus T1 - Solar Concentrating Systems Using Small Mirror Arrays JF - Journal of solar energy engineering N2 - The cost of solar tower power plants is dominated by the heliostat field making up roughly 50% of investment costs. Classical heliostat design is dominated by mirrors brought into position by steel structures and drives that guarantee high accuracies under wind loads and thermal stress situations. A large fraction of costs is caused by the stiffness requirements of the steel structure, typically resulting in ~ 20 kg/m² steel per mirror area. The typical cost figure of heliostats (figure mentioned by Solucar at Solar Paces Conference, Seville, 2006) is currently in the area of 150 €/m² caused by the increasing price of the necessary raw materials. An interesting option to reduce costs lies in a heliostat design where all moving parts are protected from wind loads. In this way, drives and mechanical layout may be kept less robust, thereby reducing material input and costs. In order to keep the heliostat at an appropriate size, small mirrors (around 10x10 cm²) have to be used, which are placed in a box with a transparent cover. Innovative drive systems are developed in order to obtain a cost-effective design. A 0,5x0,5 m² demonstration unit will be constructed. Tests of the unit are carried out with a high-precision artificial sun unit that imitates the sun’s path with an accuracy of less than 0.5 mrad and creates a beam of parallel light with a divergence of less than 4 mrad. Y1 - 2010 U6 - https://doi.org/10.1115/1.4000332 SN - 0199-6231 SN - 1528-8986 (eISSN) VL - 132 IS - 1 PB - ASME CY - New York ER - TY - JOUR A1 - Ball, Christopher Stephen A1 - Vögele, Stefan A1 - Grajewski, Matthias A1 - Kuckshinrichs, Wilhelm T1 - E-mobility from a multi-actor point of view: Uncertainties and their impacts JF - Technological Forecasting and Social Change Y1 - 2021 SN - 0040-1625 U6 - https://doi.org/10.1016/j.techfore.2021.120925 VL - 170 IS - Art. 120925 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Weber, Tobias A1 - Arent, Jan-Christoph A1 - Münch, Lukas A1 - Duhovic, Miro A1 - Balvers, Johannes Mattheus T1 - A fast method for the generation of boundary conditions for thermal autoclave simulation JF - Composites Part A N2 - Manufacturing process simulation enables the evaluation and improvement of autoclave mold concepts early in the design phase. To achieve a high part quality at low cycle times, the thermal behavior of the autoclave mold can be investigated by means of simulations. Most challenging for such a simulation is the generation of necessary boundary conditions. Heat-up and temperature distribution in an autoclave mold are governed by flow phenomena, tooling material and shape, position within the autoclave, and the chosen autoclave cycle. This paper identifies and summarizes the most important factors influencing mold heat-up and how they can be introduced into a thermal simulation. Thermal measurements are used to quantify the impact of the various parameters. Finally, the gained knowledge is applied to develop a semi-empirical approach for boundary condition estimation that enables a simple and fast thermal simulation of the autoclave curing process with reasonably high accuracy for tooling optimization. Y1 - 2016 U6 - https://doi.org/10.1016/j.compositesa.2016.05.036 SN - 1359-835X VL - 88 SP - 216 EP - 225 PB - Elsevier CY - Amsterdam ER - TY - CHAP A1 - Scholl, Ingrid A1 - Bartella, Alexander K. A1 - Moluluo, Cem A1 - Ertural, Berat A1 - Laing, Frederic A1 - Suder, Sebastian T1 - MedicVR : Acceleration and Enhancement Techniques for Direct Volume Rendering in Virtual Reality T2 - Bildverarbeitung für die Medizin 2019 : Algorithmen – Systeme – Anwendungen Y1 - 2019 SN - 978-3-658-25326-4 U6 - https://doi.org/10.1007/978-3-658-25326-4_32 SP - 152 EP - 157 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Sponagel, Stefan A1 - Baroud, Gamal A1 - Falk, R. A1 - Crookshank, M. T1 - Experimental and theoretical investigation of directional permeability of human vertebral cancellous bone for cement infiltration. G. Baroud, R. Falk, M. Crookshank, S. Sponagel, T. Steffen JF - Journal of Biomechanics. 37 (2004), H. 2 Y1 - 2004 SN - 0021-9290 SP - 189 EP - 196 ER - TY - JOUR A1 - Bode, Jürgen A1 - Bartsch, Jörg W. A1 - Boulikas, Toulikas A1 - Iber, Michaela A1 - Mielke, Christian A1 - Schübeler, Dirk A1 - Seibler, Jost A1 - Benham, Craig T1 - Transcription-promoting genomic sites in mammalia: their elucidation and architectural principles JF - Gene therapy & molecular biology Y1 - 1998 SN - 1529-9120 VL - 1 IS - 1 SP - 1 EP - 29 ER - TY - JOUR A1 - Spelthahn, Heiko A1 - Schaffrath, Sophie A1 - Coppe, Thomas A1 - Rufi, Frederic A1 - Schöning, Michael Josef T1 - Development of an electrolyte-insulator-semiconductor (EIS) based capacitive heavy metal sensor for the detection of Pb2+ und Cd2+ ions JF - Physica status solidi (a) : applications and material science N2 - Chalcogenide glass materials as membranes for potentiometric sensors for chemical analysis in solutions have been studied since more than 20 years. In this work, an electrolyte–insulator–semiconductor structure was combined with chalcogenide glass membranes prepared by means of the pulsed laser deposition technique. Depending on the membrane composition a selectivity to different ions (Cd2+ and Pb2+) is achieved. The different sensor membranes have been physically characterised using microscopy, ellipsometry, profilometry, atomic force microscopy (AFM), scanning electron microscopy (SEM) and Rutherford backscattering spectrometry (RBS). The electrochemical behaviour has been investigated via capacitance/voltage (C/V) and constant capacitance (ConCap) measurements and results in a Cd2+ sensitivity of 23.1 ± 0.6 mV per decade in a linear range from 7 × 10−6 to 10−2 mol/l and 24.4 ± 0.5 mV per decade in a linear range from 5 × 10−6 to 10−2 mol/l for Pb2+, respectively. Y1 - 2010 U6 - https://doi.org/10.1002/pssa.200983306 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 VL - 207 IS - 4 SP - 930 EP - 934 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Digel, Ilya A1 - Wehlitz, V. A1 - Kayser, Peter A1 - Figiel-Lange, A. A1 - Bassam, Rasha A1 - Rundstedt, F. von T1 - Suspension depletion approach for exemption of infected Solanum jasminoides cells from pospiviroids JF - Plant Pathology N2 - Despite numerous studies, viroid elimination from infected plants remains a very challenging task. This study introduces for the first time a novel ‘suspension depletion’ approach for exemption of Solanum jasminoides plants from viroids. The proposed method implies initial establishment of suspension cultures of the infected plant cells. The suspended cells were then physically treated (mild thermotherapy, 33 °C), which presumably delayed the replication of the viroid. The viroid concentration in the treated biomass was monitored weekly using pospiviroid-specific PCR. After 10–12 weeks of continuous treatment, a sufficient decrease in viroid concentration was observed such that the infection became undetectable by PCR. The treated single cells then gave rise to microcolonies on a solid culture medium and the obtained viroid-negative clones were further promoted to regenerate into viroid-free plants. Three years of accumulated experimental data suggests feasibility, broad applicability, and good efficacy of the proposed approach. Y1 - 2018 U6 - https://doi.org/10.1111/ppa.12750 SN - 1365-3059 VL - 67 IS - 2 SP - 358 EP - 365 PB - Wiley CY - Oxford ER - TY - JOUR A1 - Staat, Manfred A1 - Baroud, Gamal A1 - Topcu, M. A1 - Sponagel, Stefan T1 - Soft Materials in Technology and Biology – Characteristics, Properties, and Parameter Identification JF - Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.) Y1 - 2008 SN - 978-3-540-75408-4 SP - 253 EP - 315 PB - Springer CY - Berlin ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Başkurt, Oǧuz Kerim A1 - Pekcetin, C. A1 - Kandemir, F. T1 - Leukocyte activation, oxidant stress and red blood cell properties after acute, exhausting exercise in rats. Temiz, A.; Baskurt, O. K., Pekcetin, C.; Kandemir, F.; Güre, A. JF - Clinical Hemorheology and Microcirculation. 22 (2000), H. 4 Y1 - 2000 SN - 1386-0291 SP - 253 EP - 259 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Yalcin, Ozlem A1 - Resmi, Halil A1 - Başkurt, Oǧuz Kerim T1 - Can white blood cell activation be one of the major factors that affect hemorheological parameters during and after exercise? JF - Clinical Hemorheology and Microcirculation. 26 (2002), H. 3 Y1 - 2002 SN - 1386-0291 N1 - = The 11th European Symposium on Clinical Hemorheology, Rouen, France, 19-22 September 2000 SP - 189 EP - 193 ER - TY - JOUR A1 - Sponagel, Stefan A1 - Baroud, Gamal A1 - Falk, R. A1 - Crookshank, M. T1 - Corrigendum to “Experimental and theoretical investigation of directional permeability of human vertebral cancellous bone for cement infiltration”. Baroud, G.; Falk, R.; Crookshank, M.; Sponagel, S.; Steffen, T. JF - Journal of Biomechanics. 37 (2004), H. 2 Y1 - 2004 SN - 0021-9290 SP - 1802 ER - TY - JOUR A1 - Claessen, O. A1 - Grefen, Dana A1 - Mang, Thomas A1 - Dikland, H. G. A1 - Dikland, H. G. A1 - Duin, M. van T1 - Helle Fensterprofilmaterialien : Alterungsverhalten auf Basis von peroxidisch vernetztem EPDM JF - Kautschuk, Gummi, Kunststoffe : KGK Y1 - 2010 SN - 0948-3276 VL - 63 IS - 9 SP - 350 EP - 360 PB - Hüthig CY - Heidelberg ER - TY - JOUR A1 - Weber, Tobias A1 - Arent, Jan-Christoph A1 - Steffen, Lucas A1 - Balvers, Johannes Mattheus A1 - Duhovic, Miro T1 - Thermal optimization of composite autoclave molds using the shift factor approach for boundary condition estimation JF - Journal of Composite Materials Y1 - 2017 U6 - https://doi.org/10.1177/0021998317699868 SN - 1530-793X VL - 51 IS - 12 SP - 1753 EP - 1767 PB - Sage CY - London 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 - Temiz Artmann, Aysegül A1 - Başkurt, Oǧuz Kerim A1 - Edremitlioglu, M. T1 - In vitro effects of in vivo activated leukocytes on red blood cell filterability and lipid peroxidation. Baskurt, O.K.; Edremitlioglu, M.; Temiz, A. JF - Clinical Hemorheology. 14 (1994), H. 4 Y1 - 1994 SP - 591 EP - 596 ER - TY - JOUR A1 - Sponagel, Stefan A1 - Baroud, Gamal A1 - Steffen, T. A1 - Wu, J. T1 - Parameter identification for cement infiltration of osteoporotic bone JF - Poromechanics II : Proceedings of the Second Biot Conference on Poromechanics Grenoble, France 26 - 28 August 2002 / ed. by J.-L. Auriault ... Y1 - 2002 SN - 90-5809-394-8 SP - 55 EP - 58 PB - Balkema CY - Lisse [u.a.] ER - TY - JOUR A1 - Naujokat, Anke T1 - Ut rhetorica architectura – Leon Battista Alberti´s Technique of Architectural Collage / Leon Battista Albertis architektonische Collagetechnik JF - Candide : journal for architectural knowledge N2 - Leon Battista Alberti, probably the most innovative architect of early Renaissance Italy, has always fascinated scholars by virtue of the striking interpenetration of theory and practice manifest in his work. As an architect, Alberti was an autodidact. Without the benefit of the formative influence of a master or design education, the roots of his conception of architecture lie in his intellectual formation through humanistic rhetoric. The present study demonstrates with reference to a specific project — the Tempietto of the Holy Sepulchre in Florence — how Alberti’s humanist approach conditioned his method of architectural design. Y1 - 2010 SN - 1869-6465 VL - 2 SP - 73 EP - 100 PB - RWTH Aachen CY - Aachen ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Başkurt, Oǧuz Kerim A1 - Meiselman, H. J. T1 - Effect of superoxide anions on red blood cell rheologic properties. Baskurt, O. K.; Temiz, A.; Meiselman, H. J. JF - Free Radical Biology and Medicine. 24 (1998), H. 1 Y1 - 1998 SN - 0891-5849 SP - 102 EP - 110 ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Başkurt, Oǧuz Kerim A1 - Meiselman, H. J. T1 - Red blood cell aggregation in experimental sepsis . Baskurt, O. K.; Temiz, A.; Meiselman, H. J. JF - Journal of Laboratory and Clinical Medicine. 130 (1997), H. 2 Y1 - 1997 SN - 0022-2143 SP - 183 EP - 190 ER - TY - JOUR A1 - Kern, Alexander A1 - Schelthoff, Christof A1 - Mathieu, Moritz T1 - Die dynamische Blitzkugel : Wahrscheinlichkeitsberechnung für Blitzeinschläge in Gebäude JF - de - Fachzeitschrift für das Elektrohandwerk Y1 - 2010 SN - 2509-517X IS - 13-14 SP - 24 EP - 29 PB - Hüthig CY - Heidelberg ER - TY - JOUR A1 - Temiz Artmann, Aysegül A1 - Başkurt, Oǧuz Kerim A1 - Edremitlioglu, M. T1 - Effect of erythrocyte deformability on myocardial hematocrit gradient. Baskurt, O.K.; Edremitlioglu, M.; Temiz, A. JF - American Journal of Physiology: Heart and Circulatory Physiology. 268 (1995), H. 1 Y1 - 1995 SN - 0363-6135 SP - 260 EP - 264 ER - TY - JOUR A1 - Esch, Thomas T1 - Trends in der Nutzfahrzeugantriebstechnik JF - Motortechnische Zeitschrift (MTZ) N2 - Umweltzonen und Fahrverbote, kletternde Dieselpreise und steigende Straßenbenutzungsgebühren setzen dem Transportgewerbe aktuell schwer zu. Nutzfahrzeughersteller und Partner finden auf diese Herausforderungen neue Antworten mit der Erfüllung der EEV-Grenzwerte (Enhanced Environmentally Friendly Vehicle) als den gegenwärtig anspruchsvollsten europäischen Abgasstandard für Lkw und Busse. Y1 - 2010 U6 - https://doi.org/10.1007/bf03225608 SN - 0024-8525 VL - 71 IS - 10 SP - 652 EP - 658 PB - Springer Nature CY - Basel ER - TY - JOUR A1 - Biener, Ernst A1 - Sasse, Torsten A1 - Wemhoff, Thomas ED - Egloffstein, Thomas T1 - Deponie auf Deponie - Technische und genehmigungsrechtliche Aspekte JF - Band 19: Abschluss und Rekultivierung von Deponien und Altlasten 2010 : Die Umsetzung der neuen Deponieverordnung - praktische Erfahrungen im Vollzug und erste Änderungsverordnung zur neuen DepV ; Beiträge zum Seminar am 13. und 14. Oktober 2010 in Karlsruhe Y1 - 2010 SN - 978-3-939662-08-2 N1 - Seminar 2010.10.13-14, Karlsruhe SP - 73 EP - 84 PB - ICP-Eigenverlag CY - Karlsruhe ER - TY - JOUR A1 - Gronsfeld, Richard A1 - Sparla, Peter A1 - Weinnhold, Wolfgang T1 - Airborne und terrestrisches Laserscanning - neue Tools für den Talsperrenbetreiber? JF - Wasserwirtschaft Y1 - 2010 U6 - https://doi.org/10.1007/BF03241621 SN - 0043-0978 VL - 100 IS - 4 SP - 80 EP - 82 PB - Springer Vieweg CY - Wiesbaden ER - TY - JOUR A1 - Thelen, Jan A1 - Paschmann, Hans A1 - Hamelmann, Dirk T1 - Zielsichere Herstellung und Anwendung von Flüssigboden JF - bi-UmweltBau Y1 - 2010 SN - 2509-2685 SP - 48 EP - 49 PB - bi-Medien-GmbH CY - Kiel ER - TY - JOUR A1 - Ziemons, Karl A1 - Heinrichs, U. A1 - Streun, M. A1 - Pietrzyk, Uwe T1 - Validation of GEANT3 simulation studies with a dual-head PMT ClearPET™ prototype JF - 2003 IEEE Nuclear Science Symposium Conference Record, Vol. 5 N2 - The ClearPET™ project is proposed by working groups of the Crystal Clear Collaboration (CCC) to develop a 2nd generation high performance small animal positron emission tomograph (PET). High sensitivity and high spatial resolution is foreseen for the ClearPET™ camera by using a phoswich arrangement combining mixed lutetium yttrium aluminum perovskite (LuYAP:Ce) and lutetium oxyorthosilicate (LSO) scintillating crystals. Design optimizations for the first photomultiplier tube (PMT) based ClearPET camera are done with a Monte-Carlo simulation package implemented on GEANT3 (CERN, Geneva, Switzerland). A dual-head prototype has been built to test the frontend electronics and was used to validate the implementation of the GEANT3 simulation tool. Multiple simulations were performed following the experimental protocols to measure the intrinsic resolution and the sensitivity profile in axial and radial direction. Including a mean energy resolution of about 27.0% the simulated intrinsic resolution is about (1.41±0.11)mm compared to the measured of (1.48±0.06)mm. The simulated sensitivity profiles show a mean square deviation of 12.6% in axial direction and 3.6% in radial direction. Satisfactorily these results are representative for all designs and confirm the scanner geometry. Y1 - 2004 SN - 1082-3654 SP - 3053 EP - 3056 ER - TY - JOUR A1 - Khodaverdi, M. A1 - Chatziioannou, A. F. A1 - Weber, S. A1 - Ziemons, Karl A1 - Halling, H. A1 - Pietrzyk, Uwe T1 - Investigation of different MicroCT scanner configurations by GEANT4 simulations JF - IEEE Transactions on Nuclear Science N2 - This study has been performed to design the combination of the new ClearPET (ClearPET is a trademark of the Crystal Clear Collaboration), a small animal positron emission tomography (PET) system, with a micro-computed tomography (microCT) scanner. The properties of different microCT systems have been determined by simulations based on GEANT4. We will demonstrate the influence of the detector material and the X-ray spectrum on the obtained contrast. Four different detector materials (selenium, cadmium zinc telluride, cesium iodide and gadolinium oxysulfide) and two X-ray spectra (a molybdenum and a tungsten source) have been considered. The spectra have also been modified by aluminum filters of varying thickness. The contrast between different tissue types (water, air, brain, bone and fat) has been simulated by using a suitable phantom. The results indicate the possibility to improve the image contrast in microCT by an optimized combination of the X-ray source and detector material. Y1 - 2005 SN - 0018-9499 VL - 52 IS - 1 SP - 188 EP - 192 ER - TY - JOUR A1 - Blome, Hans-Joachim A1 - Chicone, Carmen A1 - Hehl, Friedrich W. A1 - Mashhoon, Bahram T1 - Nonlocal modification of Newtonian gravity JF - Physical Review D N2 - The Newtonian regime of a recent nonlocal extension of general relativity is investigated. Nonlocality is introduced via a scalar “constitutive” kernel in a special case of the translational gauge theory of gravitation, namely, the teleparallel equivalent of general relativity. In this theory, the nonlocal aspect of gravity simulates dark matter. A nonlocal and nonlinear generalization of Poisson’s equation of Newtonian gravitation is presented. The implications of nonlocality for the gravitational physics in the solar system are briefly studied. Y1 - 2010 U6 - https://doi.org/10.1103/PhysRevD.81.065020 SN - 0556-2821 VL - 81 IS - 6 EP - 065020 PB - American Physical Society CY - Melville, NY ER - TY - JOUR A1 - Timme, Michael T1 - Kündigung des Mietverhältnisses wegen nicht gezahlter Kosten eines Rechtsstreits JF - Monatsschrift für deutsches Recht N2 - Der BGH hat entschieden, dass ein Vermieter einen Wohnraummietvertrag nicht deshalb kündigen kann, weil der Mieter die Prozesskosten eines früheren, auf Zahlungsverzug gestützten Räumungsprozesses nicht begleicht. Der folgende Beitrag beleuchtet die Konsequenzen dieser Entscheidung für die mietvertragliche Praxis Y1 - 2010 U6 - https://doi.org/10.9785/ovs-mdtr-2010-1089 SN - 0340-1812 VL - 64 IS - 19 SP - 1089 EP - 1091 PB - Verlag Dr. Otto Schmidt CY - Köln ER - TY - JOUR A1 - Ziemons, Karl A1 - Bruyndonckx, P. A1 - Perez, J. M. A1 - Pietrzyk, Uwe A1 - Rato, P. A1 - Tavernier, S. T1 - Beyond ClearPET: Next Aims JF - 5th IEEE International Symposium on Biomedical Imaging: From Nano to Macro Symposium Proceedings ISBI 2008 N2 - The CRYSTAL CLEAR collaboration, in short CCC, is a consortium of 12 academic institutions, mainly from Europe, joining efforts in the area of developing instrumentation for nuclear medicine and medical imaging. In the framework of the CCC a high performance small animal PET system, called ClearPET, was developed by using new technologies in electronics and crystals in a phoswich arrangement combining two types of lutetium- based scintillator materials: LSO:Ce and LuYAP:Ce. Our next aim will be the development of hybrid image systems. Hybrid MR-PET imaging has many unique advantages for brain research. This has sparked a new research line within CCC for the development of novel MR-PET compatible technologies. MRI is not as sensitive as PET but PET has poorer spatial resolution than MRI. Two major advantages of PET are sensitivity and its ability to acquire metabolic information. To assess these innovations, the development of a 9.4T hybrid animal MR-PET scanner is proposed based on an existing 9.4T MR scanner that will be adapted to enable simultaneous acquisition of MR and PET data using cutting- edge technology for both MR and PET. Y1 - 2008 SN - 978-1-4244-2003-2 SP - 1421 EP - 1424 ER - TY - JOUR A1 - Khodaverdi, M. A1 - Chaziioannou, A. F. A1 - Weber, S. A1 - Ziemons, Karl A1 - Halling, H. A1 - Pietrzyk, Uwe T1 - Investigation of different microCT scanner configurations by GEANT4 simulations JF - 2003 IEEE Nuclear Science Symposium Conference Record, Vol. 4 N2 - This study has been performed to design the combination of the new ClearPET TM (ClearPET is a trademark of the Crystal Clear Collaboration), a small animal Positron Emission Tomography (PET) system, with a microComputed Tomography (microCT) scanner. The properties of different microCT systems have been determined by simulations based on GEANT4. We demonstrate the influence of the detector material and the X-ray spectrum on the obtained contrast. Four different detector materials (selenium, cadmium zinc telluride, cesium iodide and gadolinium oxysulfide) and two X-ray spectra (a molybdenum and a tungsten source) have been considered. The spectra have also been modified by aluminum filters of varying thickness. The contrast between different tissue types (water, air, brain, bone and fat) has been simulated by using a suitable phantom. The results indicate the possibility to improve the image contrast in microCT by an optimized combination of the X-ray source and detector material. Y1 - 2004 SN - 1082-3654 SP - 2989 EP - 2993 ER - TY - JOUR A1 - Wagner, Torsten A1 - Werner, Frederik A1 - Miyamoto, Ko-ichiro A1 - Ackermann, Hans-Josef A1 - Yoshinobu, Tatsuo A1 - Schöning, Michael Josef T1 - FPGA-based LAPS device for the flexible design of sensing sites on functional interfaces JF - Physica Status Solidi (A) N2 - The development of new interfaces for (bio-)chemical sensors requires comprehensive analyses and testing. The light-addressable potentiometric sensor (LAPS) can be used as a platform to investigate the sensitivity of a newly developed interface towards (bio-)chemical agents. LAPS measurements are spatially resolved by utilisation of focused light beams to define individual measurement spots. In this work, a new digitally modulated LAPS set-up based on an FPGA design will be introduced to increase the number of measurement spots, to shorten the measurement time and to improve the measurement accuracy. Y1 - 2010 U6 - https://doi.org/10.1002/pssa.200983320 SN - 1862-6300 N1 - Special Issue: Engineering of Functional Interfaces EnFI 2009 VL - 207 IS - 4 SP - 844 EP - 849 PB - Wiley-VCH CY - Weinheim ER - TY - CHAP A1 - Streun, M. A1 - Al-Kaddoum, R. A1 - Parl, C. A1 - Pietrzyk, Uwe A1 - Ziemons, Karl A1 - Waasen, S. van T1 - Simulation studies of optical photons in monolithic block scintillators T2 - 2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC) N2 - The interest in PET detectors with monolithic block scintillators is growing. In order to obtain high spatial resolutions dedicated positioning algorithms are required. But even an ideal algorithm can only deliver information which is provided by the detector. In this simulation study we investigated the light distribution on one surface of cuboid LSO scintillators of different size. Scintillators with a large aspect ratio (small footprint and large height) showed significant position information only for a minimum interaction depth of the gamma particle. The results allow a quantitative estimate for a useful aspect ratio. Y1 - 2012 SN - 978-1-4673-0120-6 (electronic ISBN) SN - 978-1-4673-0118-3 (print ISBN) U6 - https://doi.org/10.1109/NSSMIC.2011.6154621 SP - 1380 EP - 1382 PB - IEEE CY - New York ER - TY - JOUR A1 - Berretz, Frank A1 - Skorupa, Sascha A1 - Sander, Volker A1 - Belloum, Adam A1 - Bubak, Marian T1 - Actor-Driven Workflow Execution in Distributed Environments JF - Euro-Par 2010 Parallel Processing Workshops : HeteroPAR, HPCC, HiBB, CoreGrid, UCHPC, HPCF, PROPER, CCPI, VHPC ; Ischia, Italy, August 31 - September 3, 2010 ; revised selected papers / Mario R. Guarracino ... (eds.) Y1 - 2011 SN - 978-3-642-21877-4 N1 - Lecture Notes in Computer Science ; 6586 SP - 287 EP - 294 PB - Springer CY - Berlin ER - TY - JOUR A1 - Gerhards, M. A1 - Skorupa, Sascha A1 - Sander, Volker A1 - Pfeiffer, P. A1 - Belloum, Adam T1 - Towards a security framework for a WS-HumanTask processor JF - 7th International Conference on Network and Service Management (CNSM), 2011 Paris Y1 - 2011 SN - 978-3-901882-44-9 SP - 1 EP - 5 PB - IEEE CY - New York ER - TY - JOUR A1 - Bernau, C. R. A1 - Knödler, Matthias A1 - Emonts, Jessica A1 - Jäpel, Ronald Colin A1 - Buyel, Johannes Felix T1 - The use of predictive models to develop chromatography-based purification processes JF - Frontiers in Bioengineering and Biotechnology N2 - Chromatography is the workhorse of biopharmaceutical downstream processing because it can selectively enrich a target product while removing impurities from complex feed streams. This is achieved by exploiting differences in molecular properties, such as size, charge and hydrophobicity (alone or in different combinations). Accordingly, many parameters must be tested during process development in order to maximize product purity and recovery, including resin and ligand types, conductivity, pH, gradient profiles, and the sequence of separation operations. The number of possible experimental conditions quickly becomes unmanageable. Although the range of suitable conditions can be narrowed based on experience, the time and cost of the work remain high even when using high-throughput laboratory automation. In contrast, chromatography modeling using inexpensive, parallelized computer hardware can provide expert knowledge, predicting conditions that achieve high purity and efficient recovery. The prediction of suitable conditions in silico reduces the number of empirical tests required and provides in-depth process understanding, which is recommended by regulatory authorities. In this article, we discuss the benefits and specific challenges of chromatography modeling. We describe the experimental characterization of chromatography devices and settings prior to modeling, such as the determination of column porosity. We also consider the challenges that must be overcome when models are set up and calibrated, including the cross-validation and verification of data-driven and hybrid (combined data-driven and mechanistic) models. This review will therefore support researchers intending to establish a chromatography modeling workflow in their laboratory. KW - biopharmaceutical production process KW - Data-driven models KW - downstream processing design KW - experiment quality KW - hybrid model validation Y1 - 2022 U6 - https://doi.org/10.3389/fbioe.2022.1009102 SN - 2296-4185 (online-ressource) IS - 10 PB - Frontiers Media CY - Lausanne ER - TY - JOUR A1 - Fredebeul-Krein, Markus A1 - Knoben, Werner T1 - Long term risk sharing contracts as an approach to establish public–private partnerships for investment into next generation access networks JF - Telecommunications Policy N2 - This paper develops an investment/pricing model for the deployment of basic broadband networks which, along with other applications, is applicable to public–private partnership projects. In particular, a new investment model is suggested to be used for finance deployment over a longer term by enabling both private and public investors to participate in the roll-out of next generation access (NGA) infrastructure. This so-called “long-term risk sharing concept” has several notable benefits compared with the traditional regulatory approach. Above all, the model enables both private operators and public authorities to share the risk of investing in NGA infrastructure. Thus the model offers a way for public authorities to achieve a timely and countrywide roll-out of NGA networks, including in areas where NGA investment would otherwise not occur. Y1 - 2010 U6 - https://doi.org/10.1016/j.telpol.2010.07.011 SN - 0308-5961 N1 - Part of special issue "Public–private interplay in next generation communications" VL - 34 IS - 9 SP - 528 EP - 539 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Fredebeul-Krein, Markus T1 - Wirtschaftskrise : Staatliche Förderung von glasfaserbasierten Breitbandnetzen? JF - Wirtschaftsdienst N2 - Glasfaserbasierte Breitbandnetze werden in Deutschland auch aufgrund der Wirtschaftskrise nur sehr zögerlich ausgebaut. Markus Fredebeul-Krein hält eine staatliche Subventionierung der Breitbandnetze nur bedingt für gerechtfertigt. Private Investoren benötigen jedoch dringend Planungssicherheit durch verlässliche Regulierungsvorschriften. Y1 - 2010 SN - 0043-6275 VL - 90 IS - 2 SP - 113 EP - 117 PB - ZBW CY - Berlin ER - TY - JOUR A1 - Schlamann, M. A1 - Yoon, M.-S. A1 - Maderwald, S. A1 - Pietrzyk, Thomas A1 - Bitz, Andreas A1 - Gerwig, M. A1 - Forsting, M. A1 - Ladd, S. C. A1 - Ladd, M. E. A1 - Kastrup, O. T1 - Auswirkungen der Magnetresonanztomografie auf die Elektrophysiologie des motorischen Kortex: eine Studie mit transkranieller Magnetstimulation T1 - Effects of MRI on the electrophysiology of the motor cortex: a TMS study JF - RöFo - Fortschritte auf dem Giebiet der Röntgenstrahlen und der bildgebenden Verfahren Y1 - 2009 U6 - https://doi.org/10.1055/s-0028-1109038 SN - 1438-9029 VL - 181 IS - 3 SP - 215 EP - 219 PB - Thieme CY - Stuttgart ER - TY - JOUR A1 - Gerhards, M. A1 - Skorupa, Sascha A1 - Sander, Volker A1 - Belloum, Adam A1 - Vesunin, D. A1 - Benabdelkader, A. T1 - HisT/PLIER : A Two-Fold Provenance Approach for Grid-Enabled Scientific Workflows Using WS-VLAM JF - 12th IEEE/ACM International Conference on Grid Computing (GRID), 2011 Y1 - 2011 U6 - https://doi.org/10.1109/Grid.2011.39 SP - 224 EP - 225 PB - IEEE CY - New York ER - TY - JOUR A1 - Fredebeul-Krein, Markus T1 - Die Abschaffung der Studiengebühren ist der falsche Weg! JF - Der Ordnungspolitische Kommentar Y1 - 2010 N1 - Herausgegeben vom Institut für Wirtschaftspolitik an der Universität zu Köln sowie dem Otto-Wolff-Institut für Wirtschaftsordnung ER -