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  - 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  - Hartung, Frank
T1  - Mobile DRM Introduction: The Need for Mobile DRM
JF  - Digital Rights Management : Technological, Economic, Legal and Political Aspects / Becker, Eberhard [u.a.]
Y1  - 2003
N1  - Lecture Notes in Computer Science ; 2770
SP  - 138
EP  - 149
PB  - Springer
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Grap, Rolf Dietmar
T1  - Determining manpower requirements in a spinning mill
JF  - Chemical fibers international : CFI ; fiber polymers, fibers, texturing, and spunbonds (2003)
Y1  - 2003
SN  - 0340-3343
SP  - 455
EP  - 458
ER  - 
TY  - BOOK
A1  - Gebhardt, Andreas
T1  - Rapid Prototyping
Y1  - 2003
SN  - 3-446-21259-0
PB  - Hanser
CY  - Munich [u.a.]
ER  - 
TY  - JOUR
A1  - Förster, Arnold
A1  - Kiesslich, G.
A1  - Wacker, A.
A1  - Scholl, E.
T1  - Nonlinear charging effect of quantum dots in a p-i-n diode. Kiesslich, G.; Wacker, A.; Scholl, E.; Vitusevich, S.A.; Belyaev, A.E.; Danylyuk, S.V.; Forster, A.; Klein, N.; Henini, M.
JF  - Physical Review B. 68 (2003)
Y1  - 2003
SN  - 1550-235X
N1  - 125331 (6 Seiten)
ER  - 
TY  - JOUR
A1  - Förster, Arnold
T1  - Layer Deposition I
JF  - Fundamentals of nanoelectronics / Stefan Blügel ... (ed.). - (Lecture manuscripts of the ... Spring School of the Department of Solid State Research ; 34). - (Schriften des Forschungszentrums Jülich : Materie und Material ; 14 ; 34)
Y1  - 2003
SN  - 3-89336-319-X
SP  - C2.1
EP  - C2.13
PB  - Forschungszentrum, Zentralbibliothek
CY  - Jülich
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  - Ferrein, Alexander
A1  - Fritz, Christian
A1  - Lakemeyer, Gerhard
T1  - Extending DTGOLOG with Options / Ferrein, Alexander ; Fritz, Christian ; Lakemeyer, Gerhard
JF  - IJCAI-03, Proceedings of the Eighteenth International Joint Conference on Artificial Intelligence, Acapulco, Mexico, August 9-15, 2003
Y1  - 2003
SP  - 1391
EP  - 1393
ER  -