TY  - CHAP
A1  - Streun, M.
A1  - Al-Kaddoum, R.
A1  - Parl, C.
A1  - Pietrzyk, U.
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  - Gebhardt, Andreas
A1  - Fateri, Miranda
T1  - 3D printing and its applications
JF  - RTejournal - Forum für Rapid Technologie
N2  - Eine zunehmende Anzahl von Artikeln in Publikumszeitschriften und Journalen rückt die direkte Herstellung von Bauteilen und Figuren immer mehr in das Bewusstsein einer breiten Öffentlichkeit. Leider ergibt sich nur selten ein einigermaßen vollständiges Bild davon, wie und in welchen Lebensbereichen diese Techniken unseren Alltag verändern werden. Das liegt auch daran, dass die meisten Artikel sehr technisch geprägt sind und sich nur punktuell auf Beispiele stützen. Dieser Beitrag geht von den Bedürfnissen der Menschen aus, wie sie z.B. in der Maslow’schen Bedürfnispyramide strukturiert dargestellt sind und unterstreicht dadurch, dass 3D Printing (oder Additive Manufacturing resp. Rapid Prototyping) bereits alle Lebensbereiche erfasst hat und im Begriff ist, viele davon zu revolutionieren.
N2  - An increasing amount of popular articles focus on making models and sculptures by 3D Printing thus making more and more even private users aware of this technology. Unfortunately they mostly draw an incomplete picture of how our daily life will be influenced by this new technology. Often this is caused by a very technical point of view based on not very representative examples. This article focuses on the peoples needs as they have been structured by the so-called Maslow pyramid. Doing so, it underlines that 3D Printing (called Additive Manufacturing or Rapid Prototyping as well) already touches all aspects of life and is about to revolutionize most of them.
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:0009-2-35626
SN  - 1614-0923
VL  - 10
IS  - 1
PB  - Fachhochschule Aachen
CY  - Aachen
ER  - 
TY  - JOUR
A1  - Kirchner, Patrick
A1  - Oberländer, Jan
A1  - Suso, Henri-Pierre
A1  - Rysstad, Gunnar
A1  - Keusgen, Michael
A1  - Schöning, Michael Josef
T1  - Towards a wireless sensor system for real-time H2O2 monitoring in aseptic food processes
JF  - Physica status solidi (a)
N2  - A wireless sensor system based on the industrial ZigBee standard for low-rate wireless networking was developed that enables real-time monitoring of gaseous H2O2 during the package sterilization in aseptic food processes. The sensor system consists of a remote unit connected to a calorimetric gas sensor, which was already established in former works, and an external base unit connected to a laptop computer. The remote unit was built up by an XBee radio frequency (RF) module for data communication and a programmable system-on-chip controller to read out the sensor signal and process the sensor data, whereas the base unit is a second XBee RF module. For the rapid H2O2 detection on various locations inside the package that has to be sterilized, a novel read-out strategy of the calorimetric gas sensor was established, wherein the sensor response is measured within the short sterilization time and correlated with the present H2O2 concentration. In an exemplary measurement application in an aseptic filling machinery, the suitability of the new, wireless sensor system was demonstrated, wherein the influence of the gas velocity on the H2O2 distribution inside a package was determined and verified with microbiological tests.
KW  - calorimetric gas sensor;hydrogen peroxide;wireless sensor system
Y1  - 2013
U6  - https://doi.org/10.1002/pssa.201200920
SN  - 1862-6319
VL  - 210
IS  - 5
SP  - 877
EP  - 883
PB  - Wiley
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Khodaverdi, M.
A1  - Chatziioannou, A. F.
A1  - Weber, S.
A1  - Ziemons, Karl
A1  - Halling, H.
A1  - Pietrzyk, U.
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  - Streun, M.
A1  - Brandenburg, G.
A1  - Larue, H.
A1  - Parl, C.
A1  - Ziemons, Karl
T1  - The data acquisition system of ClearPET neuro - a small animal PET scanner
JF  - IEEE Transactions on Nuclear Science
N2  - The Crystal Clear Collaboration has developed a modular system for a small animal PET scanner (ClearPET). The modularity allows the assembly of scanners of different sizes and characteristics in order to satisfy the specific needs of the individual member institutions. The system performs depth of interaction detection by using a phoswich arrangement combining LSO and LuYAP scintillators which are coupled to Multichannel Photomultipliers (PMTs). For each PMT a free running 40 MHz ADC digitizes the signal and the complete scintillation pulse is sampled by an FPGA and sent with 20 MB/s to a PC for preprocessing. The pulse provides information about the gamma energy and the scintillator material which identifies the interaction layer. Furthermore, the exact pulse starting time is obtained from the sampled data. This is important as no hardware coincidence detection is implemented. All single events are recorded and coincidences are identified by software. The system in Jülich (ClearPET Neuro) is equipped with 10240 crystals on 80 PMTs. The paper will present an overview of the data acquisition system.
Y1  - 2006
SN  - 0018-9499
VL  - 53
IS  - 3
SP  - 700
EP  - 703
ER  - 
TY  - JOUR
A1  - Khodaverdi, M.
A1  - Weber, S.
A1  - Streun, M.
A1  - Parl, C.
A1  - Ziemons, Karl
T1  - High resolution imaging with ClearPET™ Neuro - first animal images
JF  - 2005 IEEE Nuclear Science Symposium Conference Record, Vol. 3
N2  - The ClearPET™ Neuro is the first full ring scanner within the Crystal Clear Collaboration (CCC). It consists of 80 detector modules allocated to 20 cassettes. LSO and LuYAP:Ce crystals in phoswich configuration in combination with position sensitive photomultiplier tubes are used to achieve high sensitivity and realize the acquisition of the depth of interaction (DOI) information. The complete system has been tested concerning the mechanical and electronical stability and interplay. Moreover, suitable corrections have been implemented into the reconstruction procedure to ensure high image quality. We present first results which show the successful operation of the ClearPET™ Neuro for artefact free and high resolution small animal imaging. Based on these results during the past few months the ClearPET™ Neuro System has been modified in order to optimize the performance.
Y1  - 2006
SN  - 1082-3654
SP  - 1641
EP  - 1644
ER  - 
TY  - JOUR
A1  - Streun, M.
A1  - Brandenburg, G.
A1  - Khodaverdi, M.
A1  - Larue, H.
A1  - Parl, C.
A1  - Ziemons, Karl
T1  - Timemark correction for the ClearPET™ scanners
JF  - 2005 IEEE Nuclear Science Symposium Conference Record, Vol. 4
N2  - The small animal PET scanners developed by the Crystal Clear Collaboration (ClearPETtrade) detect coincidences by analyzing timemarks which are attached to each event. The scanners are able to save complete single list mode data which allows analysis and modification of the timemarks after data acquisition. The timemarks are obtained from the digitally sampled detector pulses by calculating the baseline crossing of the rising edge of the pulse which is approximated as a straight line. But the limited sampling frequency causes a systematic error in the determination of the timemark. This error depends on the phase of the sampling clock at the time of the event. A statistical method that corrects these errors will be presented
Y1  - 2006
SN  - 1082-3654
SP  - 2057
EP  - 2060
ER  - 
TY  - CHAP
A1  - Gerhards, Michael
A1  - Sander, Volker
A1  - Belloum, Adam
T1  - Seamlessly enabling the use of cloud resources in workflows
T2  - Cloud Computing 2013 : The Fourth International Conference on Cloud Computing, GRIDs, and Virtualization : May 27 - June 1, 2013 - Valencia, Spain
Y1  - 2013
SN  - 978-1-61208-271-4
SP  - 108
EP  - 114
PB  - Curren
CY  - Red Hook, NY
ER  - 
TY  - JOUR
A1  - Jens, Otto
A1  - Kaldenhoff, E.
A1  - Kirschner-Hermanns, R.
A1  - Mühl, Thomas
A1  - Klinge, Uwe
T1  - Elongation of textile pelvic floor implants under load is related to complete loss of effective porosity, thereby favoring incorporation in scar plates
JF  - Journal of biomedical materials research. Part A
N2  - Use of textile structures for reinforcement of pelvic floor structures has to consider mechanical forces to the implant, which are quite different to the tension free conditions of the abdominal wall. Thus, biomechanical analysis of textile devices has to include the impact of strain on stretchability and effective porosity. Prolift® and Prolift + M®, developed for tension free conditions, were tested by measuring stretchability and effective porosity applying mechanical strain. For comparison, we used Dynamesh-PR4®, which was designed for pelvic floor repair to withstand mechanical strain. Prolift® at rest showed moderate porosity with little stretchability but complete loss of effective porosity at strain of 4.9 N/cm. Prolift + M® revealed an increased porosity at rest, but at strain showed high stretchability, with subsequent loss of effective porosity at strain of 2.5 N/cm. Dynamesh PR4® preserved its high porosity even under strain, but as consequence of limited stretchability. Though in tension free conditions Prolift® and Prolift + M® can be considered as large pore class I meshes, application of mechanical strain rapidly lead to collapse of pores. The loss of porosity at mechanical stress can be prevented by constructions with high structural stability. Assessment of porosity under strain was found helpful to define requirements for pelvic floor devices. Clinical studies have to prove whether devices with high porosity as well as high structural stability can improve the patients' outcome.
Y1  - 2014
U6  - https://doi.org/10.1002/jbm.a.34767
SN  - 1552-4965
VL  - 102
IS  - 4
SP  - 1079
EP  - 1084
PB  - Wiley
CY  - New York
ER  - 
TY  - CHAP
A1  - Schwarzer, Klemens
A1  - Vieira, Maria Eugenia
A1  - Müller, Christoph
A1  - Lehmann, Harry
A1  - Coutinho, Lecimara
T1  - Modular solar thermal desalination system with flat plate collector
T2  - RIO 3 - World Climate & Energy Event : proceedings of the international conference held in Rio de Janeiro, Brazil, 1 -5 december 2003 / chief-ed.: Stefan Krauter ...
Y1  - 2003
SN  - 85-902710-2-1
SP  - 281
EP  - 286
PB  - Krauter
CY  - Rio de Janeiro
ER  -