TY  - JOUR
A1  - Havermann, Marc
A1  - Seiler, F.
A1  - George, A.
A1  - Leopold, F.
T1  - Enhanced Doppler Picture Velocimetry (DPV) for Planar Velocity Measurements in High-Speed Shock Tunnel Flow / Seiler, F. ; George, A. ; Leopold, F. ; Havermann, M. ; Srulijes, J.
JF  - 10th International Symposium on Flow Visualization : Kyōto, Japan, August 26 - 29, 2002 / sponsored by International Flow Visualization Society . [Chairman:] Toshio Kobayashi
Y1  - 2002
SN  - 4906497829
N1  - International Symposium on Flow Visualization ; (10 ; 2002.08.26-29 ; Kyōto)
PB  - Visualization Society of Japan
CY  - Kyoto
ER  - 
TY  - JOUR
A1  - Wolf, Martin
A1  - Foltz, Christian
A1  - Schlick, Christopher
A1  - Luczak, Holger
T1  - Development and evaluation of a groupware system to support chemical design processes / Wolf, Martin ; Foltz, Christian ; Schlick, Christopher ; Luczak, Holger
JF  - International Journal of Human-Computer Interaction . 14 (2002), H. 2
Y1  - 2002
SN  - 1044-7318
SP  - 181
EP  - 198
PB  - -
ER  - 
TY  - JOUR
A1  - Heinrich, U.
A1  - Blum, A.
A1  - Bussmann, N.
A1  - Engels, R.
A1  - Kemmerling, G.
A1  - Weber, S.
A1  - Ziemons, Karl
T1  - Statistical studies on the light output and energy resolution of small LSO single crystals with different surface treatments combined with various reflector materials
JF  - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
N2  - The optimization of light output and energy resolution of scintillators is of special interest for the development of high resolution and high sensitivity PET. The aim of this work is to obtain statistically reliable results concerning optimal surface treatment of scintillation crystals and the selection of reflector material. For this purpose, raw, mechanically polished and etched LSO crystals (size 2×2×10 mm3) were combined with various reflector materials (Teflon tape, Teflon matrix, BaSO4) and exposed to a 22Na source. In order to ensure the statistical reliability of the results, groups of 10 LSO crystals each were measured for all combinations of surface treatment and reflector material. Using no reflector material the light output increased up to 551±35% by mechanical polishing the surface compared to 100±5% for raw crystals. Etching the surface increased the light output to 441±29%. The untreated crystals had an energy resolution of 24.6±4.0%. By mechanical polishing the surface it was possible to achieve an energy resolution of 13.2±0.8%, by etching of 14.8±0.7%. In combination with BaSO4 as reflector material the maximum increase of light output has been established to 932±57% for mechanically polished and 895±61% for etched crystals. The combination with BaSO4 also caused the best improvement of the energy resolution up to 11.6±0.2% for mechanically polished and 12.2±0.3% for etched crystals. Relating to the light output there was no significant statistical difference between the two surface treatments in combination with BaSO4. In contrast to this, the statistical results of the energy resolution have shown the combination of mechanical polishing and BaSO4 as the optimum.
Y1  - 2002
SN  - 0168-9002
N1  - Proceedings of the 6th International Conference on Inorganic Scin tillators and their Use in Scientific and Industrial Applications
VL  - 486
IS  - 1-2
SP  - 60
EP  - 66
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - A PET system with free running ADCs
JF  - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
N2  - A small PET system has been built up with two multichannel photomultipliers, which are attached to a matrix of 64 single LSO crystals each. The signal from each multiplier is being sampled continuously by a 12 bit ADC at a sampling frequency of 40 MHz. In case of a scintillation pulse a subsequent FPGA sends the corresponding set of samples together with the channel information and a time mark to the host computer. The data transfer is performed with a rate of 20 MB/s. On the host all necessary information is extracted from the data. The pulse energy is determined, coincident events are detected and multiple hits within one matrix can be identified. In order to achieve a narrow time window the pulse starting time is refined further than the resolution of the time mark (=25 ns) would allow. This is possible by interpolating between the pulse samples. First data obtained from this system will be presented. The system is part of developments for a much larger system and has been created to study the feasibility and performance of the technique and the hardware architecture.
Y1  - 2002
SN  - 0168-9002
N1  - Proceedings of the 6th International Conference on Inorganic Scin tillators and their Use in Scientific and Industrial Applications
VL  - 486
IS  - 1-2
SP  - 18
EP  - 21
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - Coincidence detection by digital processing of free-running sampled pulses
JF  - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
N2  - Coincident events in two scintillator crystals coupled to photomultipliers (PMT) are detected by processing just the digital data of the recorded pulses. For this purpose the signals from both PMTs are continuously sampled by free-running ADCs at a sampling rate of 40 MHz. For each sampled pulse the starting time is determined by processing the pulse data. Even a fairly simple interpolating algorithm results in a FWHM of about 2 ns.
Y1  - 2002
SN  - 0168-9002
VL  - 487
IS  - 3
SP  - 530
EP  - 534
ER  - 
TY  - JOUR
A1  - Khodaverdi, M.
A1  - Pauly, F.
A1  - Schroder, G.
A1  - Ziemons, Karl
A1  - Sievering, R.
A1  - Halling, H.
T1  - Preliminary studies of a micro-CT for a combined small animal PET/CT scanner
JF  - 2001 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - We are developing an X-ray computed tomography (CT) system which will be combined with a high resolution animal PET system. This permits acquisition of both molecular and anatomical images in a single machine. In particular the CT will also be utilized for the quantification of the animal PET data by providing accurate data for attenuation correction. A first prototype has been built using a commercially available plane silicon diode detector. A cone-beam reconstruction provides the images using the Feldkamp algorithm. First measurements with this system have been performed on a mouse. It could be shown that the CT setup fulfils all demands for a high quality image of the skeleton of the mouse. It is also suited for soft tissue measurements. To improve contrast and resolution and to acquire the X-ray energy further development of the system, especially the use of semiconductor detectors and iterative reconstruction algorithms are planned.
Y1  - 2002
SN  - 1082-3654
SP  - 1605
EP  - 1606
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Zimmermann, E.
A1  - Ziemons, Karl
A1  - Halling, H.
T1  - A PET system based on data processing of free-running sampled pulses
JF  - 2001 IEEE Nuclear Science Symposium Conference Record, Vol. 2
N2  - Within the developments for the Crystal Clear small animal PET project (CLEARPET) a dual head PET system has been established. The basic principle is the early digitization of the detector pulses by free running ADCs. The determination of the γ-energy and also the coincidence detection is performed by data processing of the sampled pulses on the host computer. Therefore a time mark is attached to each pulse identifying the current cycle of the 40 MHz sampling clock. In order to refine the time resolution the pulse starting time is interpolated from the samples of the pulse rise. The detector heads consist of multichannel PMTs with a single LSO scintillator crystal coupled to each channel. For each PMT only one ADC is required. The position of an event is obtained separately from trigger signals generated for each single channel. An FPGA is utilized for pulse buffering, generation of the time mark and for the data transfer to the host via a fast I/O-interface.
Y1  - 2002
SN  - 1082-3654
SP  - 693
EP  - 694
ER  - 
TY  - CHAP
A1  - Grothof, M.
A1  - Schwarte, Rudolf
A1  - Buxbaum, Bernd
A1  - Ringbeck, Thorsten
A1  - [u.a.], 
ED  - Wagner, Elmar
T1  - Product monitoring with MSM-PMD-Array
T2  - Proceedings / OPTO 2002 : an event of the Association for Sensor Technology AMA ; 14 - 16 May 2002, Exhibition Centre Erfurt, Germany / International Conference Optoelectronics, Optical Sensors & Measuring Techniques
Y1  - 2002
N1  - OPTO <5, 2002, Erfurt> ; International Conference Optoelectronics, Optical Sensors & Measuring Techniques
SP  - 41
EP  - 47
PB  - AMA Service GmbH
CY  - Wunsdorf
ER  - 
TY  - CHAP
A1  - Zang, Zhigang
A1  - Hess, Holger
A1  - Ringbeck, Thorsten
A1  - Schwarte, Rudolf
ED  - Kamerman, Gary W.
T1  - Phase-lock techniques using new correlation receivers for TOF-laser ranging
T2  - Laser radar technology and applications VII : 3 - 4 April 2002, Orlando, USA. - (SPIE proceedings series ; 4723)
Y1  - 2002
SN  - 0-8194-4473-1
SN  - 0038-7355
SN  - 0361-0748
SN  - 0277-786X
N1  - Laser Radar Technology and Applications <7, 2002, Orlando, FL>
SP  - 112
EP  - 120
PB  - SPIE, International Society for Optical Engineering
CY  - Bellingham, Wash.
ER  - 
TY  - CHAP
A1  - Buxbaum, Bernd
A1  - Schwarte, Rudolf
A1  - Ringbeck, Thorsten
A1  - [u.a.], 
ED  - Schreiber, Ulrich
T1  - MSM-PMD as correlation receiver in a new 3D-ranging system
T2  - Laser radar ranging and atmospheric lidar techniques III : 17 - 18 September 2001, Toulouse, France. - (SPIE proceedings series ; 4546)
Y1  - 2002
SN  - 0-8194-4271-2
SN  - 0038-7355
SN  - 0361-0748
SN  - 0277-786X
N1  - Laser Radar: Ranging and Atmospheric Lidar Techniques <3, 2001, Toulouse>
SP  - 145
EP  - 154
PB  - SPIE
CY  - Bellingham, Wash.
ER  - 
TY  - JOUR
A1  - Schmitz, M.
A1  - Hirsch, E.
A1  - Bongaerts, Johannes
A1  - Takors, Ralf
T1  - Pulse experiments as a prerequisite for the quantification of in vivo enzyme kinetics in aromatic amino acid pathway of Eschericia coli
JF  - Biotechnology progress
Y1  - 2002
SN  - 1520-6033 (E-Journal); 8756-7938 (Print)
VL  - Vol. 18
IS  - Iss. 5
SP  - 935
EP  - 941
ER  - 
TY  - JOUR
A1  - Bongaerts, Johannes
A1  - Bovenberg, Roel
A1  - Krämer, Marco
A1  - Müller, Ulrike
A1  - Raeven, Leon
A1  - Wubbolts, Marcel
T1  - Metabolic engineering to produce fine chemicals in Escherichia coli
JF  - Chemie - Ingenieur - Technik (CIT)
Y1  - 2002
SN  - 1522-2640 (E-Journal); 0009-286X (Print)
N1  - Printausg. in der Bibliothek vorhanden: 63 ZS 022
VL  - Vol. 74
IS  - Iss. 5
SP  - 694
ER  - 
TY  - JOUR
A1  - Gerigk, M.
A1  - Bujnicki, R.
A1  - Ganpo-Nkwenkwa, E.
A1  - Bongaerts, Johannes
A1  - Sprenger, G.
A1  - Takors, Ralf
T1  - Process control for enhanced L-phenylalanine production using different recombinant Escherichia coli strains
JF  - Biotechnology and bioengineering
Y1  - 2002
SN  - 1097-0290 (E-Journal); 0006-3592 (Print)
VL  - Vol. 80
IS  - Iss. 7
SP  - 746
EP  - 754
ER  - 
TY  - JOUR
A1  - Gerigk, M.
A1  - Maaß, D.
A1  - Kreutzer, A.
A1  - Sprenger, G.
A1  - Bongaerts, Johannes
A1  - Wubbolts, Marcel
A1  - Takors, Ralf
T1  - Enhanced pilot-scale fed-batch L-phenylalanine production with recombinant Escherichia coli by fully integrated reactive extraction
JF  - Bioprocess and biosystems engineering
Y1  - 2002
SN  - 1432-0797 (E-Journal); 1615-7605 (E-Journal); 0178-515X (Print); 1615-7591 (Print)
VL  - Vol. 25
IS  - Iss. 1
SP  - 43
EP  - 52
ER  - 
TY  - CHAP
A1  - Gligorevic, Snjezana
A1  - Sorger, Ulrich
T1  - A new approach to tracking time-variant channels
T2  - Proceedings / 5th International Symposium on Wireless Personal Multimedia Communications : WPMC : October 27 - 30, 2002, Honolulu, Hawaii ; vol. 3
Y1  - 2002
SN  - 0-7803-7442-8
SN  - 1347-6890
SP  - 1342
EP  - 1345
ER  - 
TY  - CHAP
A1  - Gligorevic, Snjezana
T1  - Joint channel estimation and equalization for fast time-variant multipath channels
T2  - Proceedings / 13th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications : PIMRC 2002 : Lisboa, Portugal, September 15 - 18, 2002
Y1  - 2002
SN  - 0-7803-7589-0
SP  - 1127
EP  - 1130
ER  - 
TY  - CHAP
A1  - Hadinejad-Mahram, Hafez
A1  - Gligorevic, Snjezana
A1  - Ritscher, Matthias
T1  - Joint iterative channel estimation and parallel interference cancellation for coded DS-CDMA
T2  - Proceeding of the International Conference on Telecommunications 2002 : [Beijing, 23 - 26 June 2002]. Vol. 2
Y1  - 2002
SP  - 566
EP  - 570
ER  - 
TY  - CHAP
A1  - Augenstein, Eckardt
A1  - Kuperjans, Isabel
A1  - Lucas, K.
ED  - Tsatsaronis,, Georgios
T1  - EUSEBIA - Decision-Support-System for Technical, Economical and Ecological Design and Evaluation of Industrial Energy Systems
T2  - ECOS 2002 : proceedings of the 15th International Conference on Efficiency, Costs, Optimization, Simulation and Environmental Impact of Energy Systems, Berlin, Germany July 3 - 5, 2002. - Vol. 1
Y1  - 2002
SN  - 3-00-009533-0
SP  - 446
EP  - 453
PB  - Techn. Univ., Inst. for Energy Engineering
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Dünkelmann, Pascal
A1  - Kolter-Jung, Doris
A1  - Nitsche, Adam
A1  - Demir, Ayhan S.
A1  - Siegert, Petra
A1  - Lingen, Bettina
A1  - Baumann, Martin
A1  - Pohl, Martina
A1  - Müller, Michael
T1  - Development of a donor-acceptor concept for enzymatic cross-coupling reactions of adehydes : the first asymmetric cross-benzoin condensation
JF  - Journal of the American Chemical Society
Y1  - 2002
SN  - 1520-5126 (E-Journal); 0002-7863 (Print)
VL  - Vol. 124
SP  - 12084
EP  - 12085
ER  - 
TY  - CHAP
A1  - Staat, Manfred
A1  - Heitzer, Michael
T1  - The restricted influence of kinematic hardening on shakedown loads
N2  - Structural design analyses are conducted with the aim of verifying the exclusion of ratcheting. To this end it is important to make a clear distinction between the shakedown range and the ratcheting range. In cyclic plasticity more sophisticated hardening models have been suggested in order to model the strain evolution observed in ratcheting experiments. The hardening models used in shakedown analysis are comparatively simple. It is shown that shakedown analysis can make quite stable predictions of admissible load ranges despite the simplicity of the underlying hardening models. A linear and a nonlinear kinematic hardening model of two-surface plasticity are compared in material shakedown analysis. Both give identical or similar shakedown ranges. Structural shakedown analyses show that the loading may have a more pronounced effect than the hardening model.
KW  - Biomedizinische Technik
KW  - Einspielen <Werkstoff>
KW  - Shakedown
KW  - Ratcheting
KW  - Bruchmechanik
KW  - shakedown
KW  - material shakedown
KW  - linear kinematic hardening
KW  - nonlinear kinematic hardening
KW  - ratchetting
Y1  - 2002
ER  -