TY  - JOUR
A1  - Dachwald, Bernd
A1  - Schmidt, Tanja D.
A1  - Seboldt, Wolfgang
A1  - Auweter-Kurtz, 
T1  - Flight Opportunities from Mars to Earth for Piloted Missions Using Continuous Thrust Propulsion / Schmidt, Tanja D. ; Dachwald, Bernd ; Seboldt, Wolfgang ; Auweter-Kurtz, Monika
Y1  - 2003
N1  - 39th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit
20-23 July 2003, Huntsville, Alabama ; AIAA 2003-4573
SP  - 1
EP  - 9
PB  - -
ER  - 
TY  - JOUR
A1  - Pfeiffer, Johann
T1  - Lernfeld 'Prozeßkette der Freiformflächenherstellung' : [Online-Ressource] / ... in Zus.-Arb. mit Johann Pfeiffer
JF  - NUMAS - Ein Lehr- und Lernsystem zur Numerischen Mathematik und Statistik : [Online-Ressource] / Projektleitung: Gisela Engeln Müllges
Y1  - 2003
N1  - Die Online-Lerneinheit ist erst nach Registrierung im Lernsystem (http://www.numas.de) einsehbar.
Stand der Aktualisierung von NUMAS®: 21.05.2004.
PB  - NUMAS.de
CY  - Aachen
ER  - 
TY  - JOUR
A1  - Heinrichs, U.
A1  - Pietrzyk, U.
A1  - Ziemons, Karl
T1  - Design optimization of the PMT-ClearPET prototypes based on simulation studies with GEANT3
JF  - 2002 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - Within the Crystal Clear Collaboration four centres are developing 2nd generation high performance small animal PET scanners for different kinds of animals and medical applications. The first prototypes are PMT-based systems including depth of interaction (DOI) detection by using a phoswich layer of LSO and LuYAP. The aim of these simulation studies is to optimize sensitivity and spatial resolution of given designs, which vary in FOVs caused by different detector configurations (ring/octagon) and sizes. For this purpose the simulation tool GEANT3 (CERN) was used. The simulations have shown that all PMT designs with one-to-one coupling of crystals have a very nonlinear axial sensitivity profile. By shifting every other PMT 1/4 of a PMT length in axial direction the sampling of the FOVs became more homogeneous. At an energy threshold of 350keV the regression coefficient increases from 0.818 for the non-shifted to 0.993 for the shifted design. Simulations of a point source centred in the FOV (threshold: 350keV) resulted in sensitivities of 4.2% for a 4×20PMT (LSO/LuYAP a 10mm) and 3.8% for a 4×16PMT (LSO/LuYAP a 8mm) ring design. The 3D-MLEM reconstruction of a point source shows the enormous improvement of resolution using a crystal double layer with DOI (3.1mm at 40mm from CFOV) instead of a 20mm single layer (11.9mm).
Y1  - 2003
SN  - 1082-3654
SP  - 682
EP  - 686
ER  - 
TY  - JOUR
A1  - Heinrichs, U.
A1  - Pietrzyk, U.
A1  - Ziemons, Karl
T1  - Design optimization of the PMT-ClearPET prototypes based on simulation studies with GEANT3
JF  - IEEE Transactions on Nuclear Science
N2  - Within the Crystal Clear Collaboration (CCC), four centers are developing second generation high performance small animal positron emission tomography (PET) scanners for different kinds of animals and medical applications. The first prototypes are photomultiplier tube (PMT)-based systems including depth of interaction (DOI) detection by using a phoswich layer of lutetium oxyorthosilicate (LSO) and lutetium yttrium aluminum perovskite (LuYAP). The aim of these simulation studies is to optimize sensitivity and spatial resolution of given designs, which vary in fields of view (FOVs) caused by different detector configurations (ring/octagon) and sizes. For this purpose the simulation tool GEANT3 (CERN, Geneva, Switzerland) was used.
Y1  - 2003
SN  - 0018-9499
VL  - 50
IS  - 5
SP  - 1428
EP  - 1432
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Saleh, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - Pulse shape discrimination of LSO and LuYAP scintillators for depth of interaction detection in PET
JF  - 2002 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - A feasible way to gain the depth of interaction information in a PET scanner is the use of phoswich detectors. In general the layer of interaction is identified front the pulse shape of the corresponding scintillator material. In this work pulses from LSO and LuYAP crystals were investigated in order to find a practical method of distinguishing. It turned out that such a pulse processing could he kept simple due to an additional slow component in the light decay of the LuYAP pulse. At the same time the short decay time guarantees that the major amount of the light output is still collected within a short pulse recording time.
Y1  - 2003
SN  - 1082-3654
SP  - 1636
EP  - 1639
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Saleh, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - Pulse shape discrimination of LSO and LuYAP scintillators for depth of interaction detection in PET
JF  - IEEE Transactions on Nuclear Science
N2  - A feasible way to gain the depth of interaction information in a positron emission tomography scanner is the use of phoswich detectors. In general, the layer of interaction is identified from the pulse shape of the corresponding scintillator material. In this work, pulses from LSO and LuYAP crystals were investigated in order to find a practical method of distinguishing. It turned out that such a pulse processing could be kept simple because of an additional slow component in the light decay of the LuYAP pulse. At the same time, the short decay time guarantees that the major amount of the light output is still collected within a short pulse recording time.
Y1  - 2003
SN  - 0018-9499
VL  - 50
IS  - 3
SP  - 344
EP  - 347
ER  - 
TY  - JOUR
A1  - Holthaus-Sellheier, Ursula
A1  - Boenert, Lothar
T1  - Alternative Brandschutzkonstruktionen führen zu Kostenreduzierungen / Boenert, Lothar ;  Holthaus, Ursula
JF  - Trockenbau, Akustik : Magazin für Planung und Ausführung (2003)
Y1  - 2003
SN  - 0179-8006
SP  - 30
EP  - 33
ER  - 
TY  - JOUR
A1  - Temiz Artmann, Aysegül
A1  - Cavdar, C.
A1  - Yenicerioglu, Y.
A1  - Caliskan, S.
T1  - The effects of intravenous iron treatment on oxidant stress and erythrocyte deformability in haemodialysis patients. Cavdar, C.; Temiz, A.; Yenicerioglu, Y.; Caliskan, S.; Celik, A.; Sifil, A.; Onvural, B.; Camsari, T.
JF  - Scandinavian Journal of Urology and Nephrology. 37 (2003), H. 1
Y1  - 2003
SN  - 0036-5599
SP  - 77
EP  - 82
ER  - 
TY  - JOUR
A1  - Fredebeul-Krein, Markus
T1  - Adopting a coherent institutional framework for the Ukrainian telecom sector: Lessons to be learnt from European and German experience
JF  - Zerkalo Nedeli  (2003)
Y1  - 2003
N1  - (Ukrainian Journal)
ER  - 
TY  - JOUR
A1  - Mayer, Claudia
A1  - Fuchs, Britta
T1  - Der neue Studiengang Communication and Multimediadesign beginnt
JF  - Fachhochschule <Aachen>: Fachblatt. 2003 (2003), H. 2
Y1  - 2003
SP  - 11
EP  - 11
ER  - 
TY  - JOUR
A1  - Mayer, Claudia
T1  - MBA-Studiengang "Entrepreneurship" in Düren bald auch mit Qualitätssiegel
JF  - Fachhochschule <Aachen>: Fachblatt. 2003 (2003), H. 2
Y1  - 2003
SN  - 1430-7707
SP  - 10
EP  - 10
ER  - 
TY  - JOUR
A1  - Oßmann, Martin
A1  - Hattrup, C.
A1  - Broeck, H. W. van der
T1  - Fast estimation techniques for digital control of resonant converters / Hattrup, C.; van der Broeck, H.W.; Ossmann, M.;
JF  - IEEE Transaction on Power Electronics. 18 (2003), H. 1
Y1  - 2003
SN  - 0885-8993
N1  - Part 2
SP  - 365
EP  - 372
ER  - 
TY  - JOUR
A1  - Havermann, Marc
A1  - Seiler, F.
A1  - George, A.
A1  - Leopold, F.
T1  - Planar Velocity Visualization in High-Speed Wedge Flow using Doppler Picture Velocimetry (DPV) compared with Particle Image Velocimetry (PIV) / Seiler, F. ; Havermann, M. ; George, A. ; Leopold, F. ; Srulijes, J.
JF  - Journal of Visualization. 6 (2003), H. 3
Y1  - 2003
SN  - 1343-8875
SP  - 253
EP  - 262
PB  - -
ER  - 
TY  - JOUR
A1  - Lindemann, Markus
T1  - webMethods sieht Koexistenz mit SAP
JF  - Computerwoche. Nr. 25 vom 20.6.2013
Y1  - 2003
SN  - 0170-5121
SP  - 16
ER  - 
TY  - JOUR
A1  - Palmer, J. W.
A1  - Lindemann, Markus
T1  - Business models and market mechanisms : evaluating efficiency in consumer electronic markets
JF  - Data base and advanced information systems. Bd. 34 (2003), H. 2
Y1  - 2003
SN  - 0105-9912
SP  - 23
EP  - 38
ER  - 
TY  - JOUR
A1  - Dielmann, Klaus-Peter
A1  - Cudina, Boris
A1  - Mehlkopf, Marcus
T1  - Einfluss der Brennstoffdaten auf die CO2-Inventarisierung : Handel mit Emissionsrechten
JF  - Euroheat and power : Kraft-Wärme-Kopplung, Nah-/Fernwärme, Contracting
Y1  - 2003
SN  - 0949-166X
VL  - 32
IS  - 9
SP  - 22
EP  - 25
ER  - 
TY  - JOUR
A1  - Hoffschmidt, Bernhard
A1  - Fend, Thomas
A1  - Jorgensen, Gary
A1  - Küster, Harald
T1  - Comparative assessment of solar concentrator materials / Fend, Thomas ; Hoffschmidt, Bernhard ; Jorgensen, Gary ; Küster, Harald ; Krüger, Dirk ; Pitz-Paal, Robert ; Riebrock, Peter ; Riffelmann, Klaus-Jürgen
JF  - Solar energy. 74 (2003), H. 2
Y1  - 2003
SN  - 0038-092X
SP  - 149
EP  - 155
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Seboldt, W.
A1  - Richter, L.
T1  - Multiple Rendezvous and Sample Return Missions to Near-Earth Asteroids Using Solar Sailcraft
JF  - Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]
Y1  - 2003
SN  - 92-9092-853-0
N1  - International Conference on Low Cost Planetary Missions <5, 2003, Noordwijk> ; International Academy of Astronautics ; European Space Research and Technology Centre
SP  - 351
EP  - 358
PB  - ESA
CY  - Noordwijk
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
T1  - Verwendung eines neuronalen Reglers und evolutionärer Algorithmen zur Berechnung optimaler interplanetarer Sonnenseglerbahnen
JF  - Deutscher Luft- und Raumfahrtkongress 2003 : München, 17. bis 20. November 2003, Motto: 100 Jahre Motorflug - 112 Jahre Menschenflug: Visionen gestalten Zukunft / Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth e.V. (DGLR). [Red.: Peter Brandt (verantwortlich)]. - Bd. 1. - (Jahrbuch ... der Deutschen Gesellschaft für Luft- und Raumfahrt)
Y1  - 2003
N1  - Deutscher Luft- und Raumfahrt-Kongreß <2003, München> ; Deutsche Gesellschaft für Luft- und Raumfahrt - Lilienthal-Oberth ; DGLR-2002-089
SP  - 211
EP  - 218
CY  - Bonn
ER  - 
TY  - JOUR
A1  - Dachwald, Bernd
A1  - Leipold, M.
A1  - Fichtner, H.
T1  - Heliopause Explorer - A Sailcraft Mission to the Outer Boundaries of the Solar System / M. Leipold ; H. Fichtner ; B. Heber  ... B. Dachwald ...
JF  - Proceedings of the Fifth IAA International Conference on Low Cost Planetary Missions : 24 - 26 September 2003, ESTEC, Noordwijk, the Netherlands / [comp. by R. A. Harris]
Y1  - 2003
SN  - 92-9092-853-0
N1  - International Conference on Low Cost Planetary Missions <5, 2003, Noordwijk> ; International Academy of Astronautics ; European Space Research and Technology Centre
SP  - 367
EP  - 375
PB  - ESA
CY  - Noordwijk
ER  -