@article{GronsfeldSparlaWeinnhold2010, author = {Gronsfeld, Richard and Sparla, Peter and Weinnhold, Wolfgang}, title = {Airborne und terrestrisches Laserscanning - neue Tools f{\"u}r den Talsperrenbetreiber?}, series = {Wasserwirtschaft}, volume = {100}, journal = {Wasserwirtschaft}, number = {4}, publisher = {Springer Vieweg}, address = {Wiesbaden}, issn = {0043-0978}, doi = {10.1007/BF03241621}, pages = {80 -- 82}, year = {2010}, language = {de} } @article{ThelenPaschmannHamelmann2010, author = {Thelen, Jan and Paschmann, Hans and Hamelmann, Dirk}, title = {Zielsichere Herstellung und Anwendung von Fl{\"u}ssigboden}, series = {bi-UmweltBau}, journal = {bi-UmweltBau}, publisher = {bi-Medien-GmbH}, address = {Kiel}, issn = {2509-2685}, pages = {48 -- 49}, year = {2010}, language = {de} } @article{BerretzSkorupaSanderetal.2010, author = {Berretz, Frank and Skorupa, Sascha and Sander, Volker and Belloum, Adam}, title = {Towards an actor-driven workflow management system for grids}, series = {Proceedings of 2010 International Symposium on Collaborative Technologies and Systems}, journal = {Proceedings of 2010 International Symposium on Collaborative Technologies and Systems}, publisher = {IEEE}, address = {Piscataway, NJ}, isbn = {978-1-4244-6619-1}, doi = {10.1109/CTS.2010.5478458}, pages = {611 -- 616}, year = {2010}, abstract = {Currently, most workflow management systems in Grid environments provide push-oriented job distribution strategies, where jobs are explicitly delegated to resources. In those scenarios the dedicated resources execute submitted jobs according to the request of a workflow engine or Grid wide scheduler. This approach has various limitations, particularly if human interactions should be integrated in workflow execution. To support human interactions with the benefit of enabling inter organizational computation and community approaches, this poster paper proposes the idea of a pull-based task distribution strategy. Here, heterogeneous resources, including human interaction, should actively select tasks for execution from a central repository. This leads to special demands regarding security issues like access control. In the established push-based job execution the resources are responsible for granting access to workflows and job initiators. In general this is done by access control lists, where users are explicitly mapped to local accounts according to their policies. In the pull-based approach the resources actively apply for job executions by sending requests to a central task repository. This means that every resource has to be able to authenticate against the repository to be authorized for task execution. In other words the authorization is relocated from the resources to the repository. The poster paper introduces current work regarding to the mentioned security aspects in the pull-based approach within the scope of the project "HiX4AGWS".}, language = {en} } @article{ZiemonsHeinrichsStreunetal.2004, author = {Ziemons, Karl and Heinrichs, U. and Streun, M. and Pietrzyk, Uwe}, title = {Validation of GEANT3 simulation studies with a dual-head PMT ClearPET™ prototype}, series = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 5}, journal = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 5}, issn = {1082-3654}, pages = {3053 -- 3056}, year = {2004}, abstract = {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.}, language = {en} } @article{KhodaverdiChatziioannouWeberetal.2005, author = {Khodaverdi, M. and Chatziioannou, A. F. and Weber, S. and Ziemons, Karl and Halling, H. and Pietrzyk, Uwe}, title = {Investigation of different MicroCT scanner configurations by GEANT4 simulations}, series = {IEEE Transactions on Nuclear Science}, volume = {52}, journal = {IEEE Transactions on Nuclear Science}, number = {1}, isbn = {0018-9499}, pages = {188 -- 192}, year = {2005}, abstract = {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.}, language = {en} } @article{SchollSchubertZieneretal.2010, author = {Scholl, Ingrid and Schubert, Nicole and Ziener, Pascal and Pietrzyk, Uwe}, title = {GPU-basiertes Volumenrendering von multimodalen medizinischen Bilddaten in Echtzeit}, series = {Bildverarbeitung f{\"u}r die Medizin 2010}, journal = {Bildverarbeitung f{\"u}r die Medizin 2010}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-642-11967-5}, pages = {400 -- 404}, year = {2010}, abstract = {Die vorliegende Arbeit zeichnet sich dadurch aus, dass registrierte unsegmentierte Volumina aus multimodalen Bilddatens{\"a}tzen (z.B. MRT, PET) gleichzeitig in einer 3D-Rekonstruktion visualisiert werden und in Echtzeit manipuliert werden k{\"o}nnen. Erm{\"o}glicht wird die Echtzeitf{\"a}higkeit durch die Programmierung der Algorithmen zur direkten Volumenvisualisierung auf der Grafikkarte mittels der neuen CUDA-Technologie. Die Zuordnung der Farbeigenschaften wird {\"u}ber 1D-Transferfunktionen f{\"u}r jedes Volumen getrennt gesteuert. So k{\"o}nnen durch die interaktive Ver{\"a}nderung der 1D-Transferfunktion Detailinformationen aus den zwei Bilddatens{\"a}tzen getrennt kontrolliert werden und die Vorteile der verschiedenen Bildmodalit{\"a}ten in einer Visualisierung genutzt werden. Mittels dieses interaktiven Frameworks k{\"o}nnen neue Erkenntnisse insbesondere {\"u}ber neurodegenerativen Erkrankungen gewonnen werden.}, language = {de} } @article{BlomeChiconeHehletal.2010, author = {Blome, Hans-Joachim and Chicone, Carmen and Hehl, Friedrich W. and Mashhoon, Bahram}, title = {Nonlocal modification of Newtonian gravity}, series = {Physical Review D}, volume = {81}, journal = {Physical Review D}, number = {6}, publisher = {American Physical Society}, address = {Melville, NY}, issn = {0556-2821}, doi = {10.1103/PhysRevD.81.065020}, year = {2010}, abstract = {The Newtonian regime of a recent nonlocal extension of general relativity is investigated. Nonlocality is introduced via a scalar "constitutive" kernel in a special case of the translational gauge theory of gravitation, namely, the teleparallel equivalent of general relativity. In this theory, the nonlocal aspect of gravity simulates dark matter. A nonlocal and nonlinear generalization of Poisson's equation of Newtonian gravitation is presented. The implications of nonlocality for the gravitational physics in the solar system are briefly studied.}, language = {en} } @article{Timme2010, author = {Timme, Michael}, title = {K{\"u}ndigung des Mietverh{\"a}ltnisses wegen nicht gezahlter Kosten eines Rechtsstreits}, series = {Monatsschrift f{\"u}r deutsches Recht}, volume = {64}, journal = {Monatsschrift f{\"u}r deutsches Recht}, number = {19}, publisher = {Verlag Dr. Otto Schmidt}, address = {K{\"o}ln}, issn = {0340-1812}, doi = {10.9785/ovs-mdtr-2010-1089}, pages = {1089 -- 1091}, year = {2010}, abstract = {Der BGH hat entschieden, dass ein Vermieter einen Wohnraummietvertrag nicht deshalb k{\"u}ndigen kann, weil der Mieter die Prozesskosten eines fr{\"u}heren, auf Zahlungsverzug gest{\"u}tzten R{\"a}umungsprozesses nicht begleicht. Der folgende Beitrag beleuchtet die Konsequenzen dieser Entscheidung f{\"u}r die mietvertragliche Praxis}, language = {de} } @article{KowollikSchnitzlerBisellietal.2010, author = {Kowollik, Silvia and Schnitzler, Thomas and Biselli, Manfred and Krueger, R. and Zang, Werner and Peuscher, A. and Schillberg, S. and Fischer, R.}, title = {Die Rolle des Respirationsquotienten in der Zellkulturfermentation}, series = {Chemie Ingenieur Technik}, volume = {82}, journal = {Chemie Ingenieur Technik}, number = {9}, publisher = {Wiley-VCH}, address = {Weinheim}, isbn = {Chemie Ingenieur Tec}, doi = {10.1002/cite.201050393}, pages = {1505 -- 1506}, year = {2010}, abstract = {In der biopharmazeutischen Industrie werden rekombinante Proteine und monoklonale Antik{\"o}rper in Zellkulturfermentationen produziert, da nur humane oder tierische Zelllinien {\"u}ber die F{\"a}higkeit der Glykosylierung verf{\"u}gen. Um hohe Produktausbeuten in ausgezeichneter Qualit{\"a}t zu erzielen, ist eine funktionst{\"u}chtige Prozesskontrolle unerl{\"a}sslich. Hierzu wurde in Kooperation mit der Firma Hitec Zang GmbH die HiSense� Pr{\"a}zisionsabgasanalytik entwickelt, die auf Basis der vollautomatischen Ermittlung des Respirationsquotienten (RQ; Verh{\"a}ltnis vonKohlendioxidbildungsrate (CER) zu Sauerstoffaufnahmerate (OTR)) einen Fermentationsprozess nicht-invasiv {\"u}berwacht. Der RQ kann in Hybridoma- und CHO-Zellen (s. Abb.) in sowohl serumhaltigen als auch serumfreien Medien erfolgreich ermittelt werden. Hier spiegeln die CER und die OTR das Wachstumsverhalten der kultivierten CHO-Zellen wider. Der RQ nimmt dabei Werte zwischen 0,9 und 1,2 an. Dies l{\"a}sst auf verschiedene Stoffwechselaktivit{\"a}ten schließen. Da die momentane industrielle Prozesskontrolle auf gemessenen Sauerstoffaufnahmeraten oder entsprechende Offline-Analytiken der Metaboliten basieren, soll durch die vollautomatische RQ-Ermittlung ein neues Verfahren zur Fermentations{\"u}berwachung etabliert werden. Bisher war diese, in bakteriellen Kultivierungen standardisierte Methode, aufgrund der schwierigen CER-Berechnung bei Zellkulturen keine ad{\"a}quate Alternative.}, language = {de} } @article{ZiemonsBruyndonckxPerezetal.2008, author = {Ziemons, Karl and Bruyndonckx, P. and Perez, J. M. and Pietrzyk, Uwe and Rato, P. and Tavernier, S.}, title = {Beyond ClearPET: Next Aims}, series = {5th IEEE International Symposium on Biomedical Imaging: From Nano to Macro Symposium Proceedings ISBI 2008}, journal = {5th IEEE International Symposium on Biomedical Imaging: From Nano to Macro Symposium Proceedings ISBI 2008}, isbn = {978-1-4244-2003-2}, pages = {1421 -- 1424}, year = {2008}, abstract = {The CRYSTAL CLEAR collaboration, in short CCC, is a consortium of 12 academic institutions, mainly from Europe, joining efforts in the area of developing instrumentation for nuclear medicine and medical imaging. In the framework of the CCC a high performance small animal PET system, called ClearPET, was developed by using new technologies in electronics and crystals in a phoswich arrangement combining two types of lutetium- based scintillator materials: LSO:Ce and LuYAP:Ce. Our next aim will be the development of hybrid image systems. Hybrid MR-PET imaging has many unique advantages for brain research. This has sparked a new research line within CCC for the development of novel MR-PET compatible technologies. MRI is not as sensitive as PET but PET has poorer spatial resolution than MRI. Two major advantages of PET are sensitivity and its ability to acquire metabolic information. To assess these innovations, the development of a 9.4T hybrid animal MR-PET scanner is proposed based on an existing 9.4T MR scanner that will be adapted to enable simultaneous acquisition of MR and PET data using cutting- edge technology for both MR and PET.}, language = {en} } @article{KhodaverdiChaziioannouWeberetal.2004, author = {Khodaverdi, M. and Chaziioannou, A. F. and Weber, S. and Ziemons, Karl and Halling, H. and Pietrzyk, Uwe}, title = {Investigation of different microCT scanner configurations by GEANT4 simulations}, series = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 4}, journal = {2003 IEEE Nuclear Science Symposium Conference Record, Vol. 4}, issn = {1082-3654}, pages = {2989 -- 2993}, year = {2004}, abstract = {This study has been performed to design the combination of the new ClearPET TM (ClearPET is a trademark of the Crystal Clear Collaboration), a small animal Positron Emission Tomography (PET) system, with a microComputed Tomography (microCT) scanner. The properties of different microCT systems have been determined by simulations based on GEANT4. We 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.}, language = {en} } @article{SchmittSchollCaietal.2010, author = {Schmitt, Robert and Scholl, Ingrid and Cai, Yu and Xia, Ji and Dziwoki, Paul and Harding, Martin and Pavim, Alberto}, title = {Machine vision system for inline inspection in carbide insert production}, series = {Proceedings of the 36th International MATADOR Conference}, journal = {Proceedings of the 36th International MATADOR Conference}, publisher = {Springer}, address = {Berlin}, isbn = {978-1-84996-431-9}, doi = {10.1007/978-1-84996-432-6_77}, pages = {339 -- 342}, year = {2010}, abstract = {In steps of the production chain of carbide inserts, such as unloading or packaging, the conformity test of the insert type is done manually, which causes a statistic increase of errors due to monotony and fatigue of the worker and the wide variety of the insert types. A machine vision system is introduced that captures digital frames of the inserts in the production line, analyses inspects automatically and measures four quality features: coating colour, edge radius, plate shape and chip-former geometry. This new method has been tested on several inserts of different types and has shown that the prevalent insert types can be inspected and robustly classified in real production environment and therefore improves the manufacturing automation.}, language = {en} } @article{WagnerWernerMiyamotoetal.2010, author = {Wagner, Torsten and Werner, Frederik and Miyamoto, Ko-ichiro and Ackermann, Hans-Josef and Yoshinobu, Tatsuo and Sch{\"o}ning, Michael Josef}, title = {FPGA-based LAPS device for the flexible design of sensing sites on functional interfaces}, series = {Physica Status Solidi (A)}, volume = {207}, journal = {Physica Status Solidi (A)}, number = {4}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6300}, doi = {10.1002/pssa.200983320}, pages = {844 -- 849}, year = {2010}, abstract = {The development of new interfaces for (bio-)chemical sensors requires comprehensive analyses and testing. The light-addressable potentiometric sensor (LAPS) can be used as a platform to investigate the sensitivity of a newly developed interface towards (bio-)chemical agents. LAPS measurements are spatially resolved by utilisation of focused light beams to define individual measurement spots. In this work, a new digitally modulated LAPS set-up based on an FPGA design will be introduced to increase the number of measurement spots, to shorten the measurement time and to improve the measurement accuracy.}, language = {en} } @inproceedings{StreunAlKaddoumParletal.2012, author = {Streun, M. and Al-Kaddoum, R. and Parl, C. and Pietrzyk, Uwe and Ziemons, Karl and Waasen, S. van}, title = {Simulation studies of optical photons in monolithic block scintillators}, series = {2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC)}, booktitle = {2011 IEEE Nuclear Science Symposium Conference Record (NSS/MIC)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-4673-0120-6 (electronic ISBN)}, doi = {10.1109/NSSMIC.2011.6154621}, pages = {1380 -- 1382}, year = {2012}, abstract = {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.}, language = {en} } @article{BerretzSkorupaSanderetal.2011, author = {Berretz, Frank and Skorupa, Sascha and Sander, Volker and Belloum, Adam and Bubak, Marian}, title = {Actor-Driven Workflow Execution in Distributed Environments}, series = {Euro-Par 2010 Parallel Processing Workshops : HeteroPAR, HPCC, HiBB, CoreGrid, UCHPC, HPCF, PROPER, CCPI, VHPC ; Ischia, Italy, August 31 - September 3, 2010 ; revised selected papers / Mario R. Guarracino ... (eds.)}, journal = {Euro-Par 2010 Parallel Processing Workshops : HeteroPAR, HPCC, HiBB, CoreGrid, UCHPC, HPCF, PROPER, CCPI, VHPC ; Ischia, Italy, August 31 - September 3, 2010 ; revised selected papers / Mario R. Guarracino ... (eds.)}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-642-21877-4}, pages = {287 -- 294}, year = {2011}, language = {en} } @article{GerhardsSkorupaSanderetal.2011, author = {Gerhards, M. and Skorupa, Sascha and Sander, Volker and Pfeiffer, P. and Belloum, Adam}, title = {Towards a security framework for a WS-HumanTask processor}, series = {7th International Conference on Network and Service Management (CNSM), 2011 Paris}, journal = {7th International Conference on Network and Service Management (CNSM), 2011 Paris}, publisher = {IEEE}, address = {New York}, isbn = {978-3-901882-44-9}, pages = {1 -- 5}, year = {2011}, language = {en} } @article{BernauKnoedlerEmontsetal.2022, author = {Bernau, C. R. and Kn{\"o}dler, Matthias and Emonts, Jessica and J{\"a}pel, Ronald Colin and Buyel, Johannes Felix}, title = {The use of predictive models to develop chromatography-based purification processes}, series = {Frontiers in Bioengineering and Biotechnology}, journal = {Frontiers in Bioengineering and Biotechnology}, number = {10}, publisher = {Frontiers Media}, address = {Lausanne}, issn = {2296-4185 (online-ressource)}, doi = {10.3389/fbioe.2022.1009102}, pages = {25 Seiten}, year = {2022}, abstract = {Chromatography is the workhorse of biopharmaceutical downstream processing because it can selectively enrich a target product while removing impurities from complex feed streams. This is achieved by exploiting differences in molecular properties, such as size, charge and hydrophobicity (alone or in different combinations). Accordingly, many parameters must be tested during process development in order to maximize product purity and recovery, including resin and ligand types, conductivity, pH, gradient profiles, and the sequence of separation operations. The number of possible experimental conditions quickly becomes unmanageable. Although the range of suitable conditions can be narrowed based on experience, the time and cost of the work remain high even when using high-throughput laboratory automation. In contrast, chromatography modeling using inexpensive, parallelized computer hardware can provide expert knowledge, predicting conditions that achieve high purity and efficient recovery. The prediction of suitable conditions in silico reduces the number of empirical tests required and provides in-depth process understanding, which is recommended by regulatory authorities. In this article, we discuss the benefits and specific challenges of chromatography modeling. We describe the experimental characterization of chromatography devices and settings prior to modeling, such as the determination of column porosity. We also consider the challenges that must be overcome when models are set up and calibrated, including the cross-validation and verification of data-driven and hybrid (combined data-driven and mechanistic) models. This review will therefore support researchers intending to establish a chromatography modeling workflow in their laboratory.}, language = {en} } @article{FredebeulKreinKnoben2010, author = {Fredebeul-Krein, Markus and Knoben, Werner}, title = {Long term risk sharing contracts as an approach to establish public-private partnerships for investment into next generation access networks}, series = {Telecommunications Policy}, volume = {34}, journal = {Telecommunications Policy}, number = {9}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0308-5961}, doi = {10.1016/j.telpol.2010.07.011}, pages = {528 -- 539}, year = {2010}, abstract = {This paper develops an investment/pricing model for the deployment of basic broadband networks which, along with other applications, is applicable to public-private partnership projects. In particular, a new investment model is suggested to be used for finance deployment over a longer term by enabling both private and public investors to participate in the roll-out of next generation access (NGA) infrastructure. This so-called "long-term risk sharing concept" has several notable benefits compared with the traditional regulatory approach. Above all, the model enables both private operators and public authorities to share the risk of investing in NGA infrastructure. Thus the model offers a way for public authorities to achieve a timely and countrywide roll-out of NGA networks, including in areas where NGA investment would otherwise not occur.}, language = {en} } @article{FredebeulKrein2010, author = {Fredebeul-Krein, Markus}, title = {Wirtschaftskrise : Staatliche F{\"o}rderung von glasfaserbasierten Breitbandnetzen?}, series = {Wirtschaftsdienst}, volume = {90}, journal = {Wirtschaftsdienst}, number = {2}, publisher = {ZBW}, address = {Berlin}, issn = {0043-6275}, pages = {113 -- 117}, year = {2010}, abstract = {Glasfaserbasierte Breitbandnetze werden in Deutschland auch aufgrund der Wirtschaftskrise nur sehr z{\"o}gerlich ausgebaut. Markus Fredebeul-Krein h{\"a}lt eine staatliche Subventionierung der Breitbandnetze nur bedingt f{\"u}r gerechtfertigt. Private Investoren ben{\"o}tigen jedoch dringend Planungssicherheit durch verl{\"a}ssliche Regulierungsvorschriften.}, language = {de} } @article{SchlamannYoonMaderwaldetal.2009, author = {Schlamann, M. and Yoon, M.-S. and Maderwald, S. and Pietrzyk, Thomas and Bitz, Andreas and Gerwig, M. and Forsting, M. and Ladd, S. C. and Ladd, M. E. and Kastrup, O.}, title = {Auswirkungen der Magnetresonanztomografie auf die Elektrophysiologie des motorischen Kortex: eine Studie mit transkranieller Magnetstimulation}, series = {R{\"o}Fo - Fortschritte auf dem Giebiet der R{\"o}ntgenstrahlen und der bildgebenden Verfahren}, volume = {181}, journal = {R{\"o}Fo - Fortschritte auf dem Giebiet der R{\"o}ntgenstrahlen und der bildgebenden Verfahren}, number = {3}, publisher = {Thieme}, address = {Stuttgart}, issn = {1438-9029}, doi = {10.1055/s-0028-1109038}, pages = {215 -- 219}, year = {2009}, language = {de} }