TY - JOUR A1 - Hellwig, Angelika A1 - Volkmann, Lutz T1 - Neighborhood and degree conditions for super-edge-connected bipartite digraphs JF - Results in mathematics Y1 - 2004 SN - 1420-9012 (E-Journal); 1422-6383 (Print) VL - Vol. 45 IS - Iss. 1-2 SP - 45 EP - 58 ER - TY - JOUR A1 - Hellwig, Angelika A1 - Volkmann, Lutz T1 - Maximally local-edge-connected graphs and digraphs JF - Ars combinatoria Y1 - 2004 SN - 0381-7032 VL - Vol. 72 SP - 295 EP - 306 ER - TY - JOUR A1 - Hellwig, Angelika A1 - Rautenbach, Dieter A1 - Volkmann, Lutz T1 - Note on the connectivity of line graphs JF - Information processing letters Y1 - 2004 SN - 1872-6119 (E-Journal); 0020-0190 (Print) VL - Vol. 91 IS - Iss. 1 SP - 7 EP - 10 ER - TY - CHAP A1 - Döring, Bernd A1 - Sedlacek, Gerhard T1 - Improvement of thermal comfort in light weight buildings made of steel with new concepts for slab systems T2 - 10th Nordic Steel Construction Conference, Copenhagen, Denmark 7-9. June 2004: NSCC 2004 : proceedings Y1 - 2004 SP - 35 EP - 44 PB - Danish Steel Inst. CY - Copenhagen ER - TY - JOUR A1 - Dilthey, Ulrich A1 - Brandenburg, Annette A1 - Schleser, Markus T1 - Dispensing and application of unfilled adhesives in the micro range JF - Welding and cutting. 3 (2004), H. 4 Y1 - 2004 SN - 1612-3433 SP - 250 EP - 254 ER - TY - CHAP A1 - Dilthey, Ulrich A1 - Mund, F. A1 - Raupach, Michael A1 - Schleser, Markus A1 - Walk-Lauffer, Bernd T1 - Improvement of textile reinforced concrete by polymer additives T2 - ICPIC '04 : 11th International Congress on Polymers in Concrete : 2nd-4th June, 2004 at BAM, Berlin, Germany : proceedings / ed. by M. Maultzsch Y1 - 2004 SN - 3-00-013706-8 SP - 469 EP - 476 PB - BAM CY - Berlin ER - TY - CHAP A1 - Walk-Lauffer, Bernd A1 - Raupach, Michael A1 - Dilger, Klaus A1 - Böhm, Stefan A1 - Mundt, F. A1 - Dilthey, Ulrich A1 - Schleser, Markus T1 - The interconnection between inner filaments of textile reinforcement by means of polymer modified concrete T2 - Proceedings of the First International Conference on Innovative Materials and Technologies for Construction and Restoration : : Lecce, June 6 - 9, 2004 / Università degli Studi di Lecce / ed. Antonio La Tegola. Vol. 1: Key-notes, materials, construction Y1 - 2004 SP - 150 EP - 159 PB - Liguori CY - Napoli ER - TY - JOUR A1 - Auffray, E. A1 - Bruyndonckx, P. A1 - Devroede, O. A1 - Fedorov, A. A1 - Ziemons, Karl T1 - The ClearPET project JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment N2 - The Crystal Clear Collaboration has designed and is building a high-resolution small animal PET scanner. The design is based on the use of the Hamamatsu R7600-M64 multi-anode photomultiplier tube and a LSO/LuYAP phoswich matrix with one to one coupling between the crystals and the photo-detector. The complete system will have 80 PM tubes in four rings with an inner diameter of 137 mm and an axial field of view of 110 mm. The PM pulses are digitized by free-running ADCs and digital data processing determines the gamma energy, the phoswich layer and even the pulse arrival time. Single gamma interactions are recorded and coincidences are found by software. The gantry allows rotation of the detector modules around the field of view. Simulations, and measurements a 2×4 module test set-up predict a spatial resolution of 1.5 mm in the centre of the field of view and a sensitivity of 5.9% for a point source in the centre of the field of view. Y1 - 2004 SN - 0168-9002 N1 - Proceedings of the 2nd International Conference on Imaging Technologies in Biomedical Sciences VL - 527 IS - 1-2 SP - 171 EP - 174 ER - TY - JOUR A1 - Ziemons, Karl A1 - Heinrichs, U. A1 - Streun, M. A1 - Pietrzyk, U. 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 - Christ, D. A1 - Hollendung, A. A1 - Larue, H. A1 - Parl, C. A1 - Streun, M. A1 - Weber, S. A1 - Ziemons, Karl A1 - Halling, H. T1 - Homogenization of the MultiChannel PM gain by inserting light attenuating masks JF - 2003 IEEE Nuclear Science Symposium Conference Record, Vol. 4 N2 - MultiChannel Photomultipliers (PM), like the R7600-00-M64 or R5900-00-M64 from Hamamatsu, are often chosen as photodetectors in high-resolution positron emission tomography (PET). A major problem of this PM is the nonuniform channel gain. In order to solve this problem, light attenuating masks were created. The aim of the masks is a homogenization of the output of all 64 channels using different hole sizes at the channel positions. The hole area, which is individually defined for the different channels, is inversely proportional to the channel gain. The measurements by inserting light attenuating masks improved a homogenization to a ratio of 1:1.2. Y1 - 2004 SN - 1082-3654 SP - 2382 EP - 2385 ER -