TY - JOUR A1 - Clausnitzer, Julian A1 - Kleefeld, Andreas T1 - A spectral Galerkin exponential Euler time-stepping scheme for parabolic SPDEs on two-dimensional domains with a C² boundary JF - Discrete and Continuous Dynamical Systems - Series B N2 - We consider the numerical approximation of second-order semi-linear parabolic stochastic partial differential equations interpreted in the mild sense which we solve on general two-dimensional domains with a C² boundary with homogeneous Dirichlet boundary conditions. The equations are driven by Gaussian additive noise, and several Lipschitz-like conditions are imposed on the nonlinear function. We discretize in space with a spectral Galerkin method and in time using an explicit Euler-like scheme. For irregular shapes, the necessary Dirichlet eigenvalues and eigenfunctions are obtained from a boundary integral equation method. This yields a nonlinear eigenvalue problem, which is discretized using a boundary element collocation method and is solved with the Beyn contour integral algorithm. We present an error analysis as well as numerical results on an exemplary asymmetric shape, and point out limitations of the approach. KW - Nonlinear eigenvalue problems KW - Boundary integral equations, KW - Exponential Euler scheme, KW - Parabolic SPDEs Y1 - 2024 U6 - https://doi.org/10.3934/dcdsb.2023148 SN - 1531-3492 SN - 1553-524X (eISSN) VL - 29 IS - 4 SP - 1624 EP - 1651 PB - AIMS CY - Springfield ER - TY - JOUR A1 - Monakhova, Yulia A1 - Diehl, Bernd W. K. T1 - A step towards optimization of the qNMR workflow: proficiency testing exercise at an GxP-accredited laboratory JF - Applied Magnetic Resonance N2 - Quantitative nuclear magnetic resonance (qNMR) is considered as a powerful tool for multicomponent mixture analysis as well as for the purity determination of single compounds. Special attention is currently paid to the training of operators and study directors involved in qNMR testing. To assure that only qualified personnel are used for sample preparation at our GxP-accredited laboratory, weighing test was proposed. Sixteen participants performed six-fold weighing of the binary mixture of dibutylated hydroxytoluene (BHT) and 1,2,4,5-tetrachloro-3-nitrobenzene (TCNB). To evaluate the quality of data analysis, all spectra were evaluated manually by a qNMR expert and using in-house developed automated routine. The results revealed that mean values are comparable and both evaluation approaches are free of systematic error. However, automated evaluation resulted in an approximately 20% increase in precision. The same findings were revealed for qNMR analysis of 32 compounds used in pharmaceutical industry. Weighing test by six-fold determination in binary mixtures and automated qNMR methodology can be recommended as efficient tools for evaluating staff proficiency. The automated qNMR method significantly increases throughput and precision of qNMR for routine measurements and extends application scope of qNMR. Y1 - 2021 U6 - https://doi.org/10.1007/s00723-021-01324-3 SN - 1613-7507 N1 - Corresponding author: Yulia Monakhova VL - 52 SP - 581 EP - 593 PB - Springer Nature CY - Wien ER - TY - JOUR A1 - Reißel, Martin A1 - Bitsch, G. A1 - Stamm, H. T1 - A Stern Door Slam Fatigue Calculation / Bitsch, G. ; Reißel, M. ; Stamm, H. JF - Proceedings of the 18. CAD-FEM Users Meeting Y1 - 2000 ER - TY - JOUR A1 - Faßbender, Heinz A1 - Maneth, Sebastian T1 - A strict border for the decidability of e-unification for recursive functions / Faßbender, Heinz ; Maneth, Sebastian JF - Journal of functional and logic programming. 1998 (1998), H. 4 Y1 - 1998 SN - 1080-5230 ER - TY - JOUR A1 - Faßbender, Heinz A1 - Maneth, Sebastian T1 - A strict border for the decidability of e-unification for recursive functions / Faßbender, Heinz ; Maneth, Sebastian JF - Algebraic and logic programming : proceedings / 5th International Conference, ALP '96, Aachen, Germany, September 25 - 27, 1996. Michael Hanus ... (ed.) Y1 - 1996 SN - 3-540-61735-3 N1 - (Lecture notes in computer science ; 1139) SP - 194 EP - 208 PB - Springer CY - Berlin [u.a.] ER - TY - JOUR A1 - Heuermann, Holger T1 - A Synthesis Technique for Mono- and Mixed-Mode Symmetrical Filter JF - Conference proceedings : Tuesday 12th, Wednesday 13th and Thursday 14th October, [RAI International Exhibition and Congress Centre, Amsterdam ; part of European Microwave Week 2004] / EuMA, European Microwave Association . Vol. 1 Y1 - 2004 SN - 1-580-53992-0 N1 - European Microwave Conference ; (34, 2004, Amsterdam) ; European Microwave Week ; (7, 2004, Amsterdam) SP - 309 EP - 312 PB - Horizon House Publ CY - London ER - TY - JOUR A1 - Kob, Malte A1 - Frauenrath, Tobias T1 - A system for parallel measurement of glottis opening and larynx position JF - Biomedical Signal Processing and Control N2 - The simultaneous assessment of glottal dynamics and larynx position can be beneficial for the diagnosis of disordered voice or speech production and swallowing. Up to now, methods either concentrate on assessment of the glottis opening using optical, acoustical or electrical (electroglottography, EGG) methods, or on visualisation of the larynx position using ultrasound, computer tomography or magnetic resonance imaging techniques. The method presented here makes use of a time-multiplex measurement approach of space-resolved transfer impedances through the larynx. The fast sequence of measurements allows a quasi simultaneous assessment of both larynx position and EGG signal using up to 32 transmit–receive signal paths. The system assesses the dynamic opening status of the glottis as well as the vertical and back/forward motion of the larynx. Two electrode-arrays are used for the measurement of the electrical transfer impedance through the neck in different directions. From the acquired data the global and individual conductivity is calculated as well as a 2D point spatial representation of the minimum impedance. The position information is shown together with classical EGG signals allowing a synchronous visual assessment of glottal area and larynx position. A first application to singing voice analysis is presented that indicate a high potential of the method for use as a non-invasive tool in the diagnosis of voice, speech, and swallowing disorders. KW - EGG KW - Transfer impedance KW - Tomography KW - Larynx position KW - Voice assessment Y1 - 2009 U6 - https://doi.org/10.1016/j.bspc.2009.03.004 SN - 1746-8108 VL - 4 IS - 3 SP - 221 EP - 228 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Wissenbach, U. A1 - Six, S. A1 - Bongaerts, Johannes A1 - Ternes, D. A1 - Steinwachs, S. A1 - Unden, G. T1 - A third periplasmic transport system for l-arginine in Escherichia coli: molecular characterization of the artPIQMJ genes, arginine binding and transport JF - Molecular microbiology Y1 - 1995 SN - 1365-2958 (E-Journal); 0950-382x (Print) VL - Vol. 17 IS - Iss. 4 SP - 675 EP - 686 ER - TY - JOUR A1 - Gebhardt, Michael A1 - Jarke, Matthias A1 - Jacobs, Stephan T1 - A Toolkit for Negotiation Support Interfaces to Multidimensional Data JF - SIGMOD 1997 : proceedings ACM SIGMOD International Conference on Management of Data, May 13 - 15, 1997, Tucson, Arizona, USA / ed. by Joan M. Peckman Y1 - 1997 SN - 0897919114 N1 - International Conference on Management of Data ; (1997, Tucson, Ariz.) PB - ACM Press CY - New York, NY ER - TY - JOUR A1 - Jochim, Haldor E. T1 - A traffic resistance model of long-distance travel JF - Networks for mobility : 2nd international symposium, September 29 - October 1, 2004, Stuttgart, Germany ; proceedings ; abstracts and CD-ROM / [2nd International Symposium on Networks for Mobility]. FOVUS, Centre of Transportation Research, University of Y1 - 2004 SN - 3-89301-180-3 N1 - International Symposium on Networks for Mobility (2, 2004, Stuttgart) PB - FOVUS CY - Stuttgart ER - TY - JOUR A1 - Kraff, Oliver A1 - Bitz, Andreas A1 - Breyer, Tobias A1 - Kruszona, Stefan A1 - Maderwald, Stefan A1 - Brote, Irina A1 - Gizewski, Elke R. A1 - Ladd, Mark E. A1 - Quick, Harald H. T1 - A transmit/receive radiofrequency array for imaging the carotid arteries at 7 Tesla: coil design and first in vivo results JF - Investigative Radiology N2 - Objective: To develop a transmit/receive radiofrequency (RF) array for magnetic resonance imaging (MRI) of the carotid arteries at 7 T. The prototype is characterized in numerical simulations and bench measurements, and the feasibility of plaque imaging at 7 T is demonstrated in first in vivo images. Materials and Methods: The RF phased array coil consists of 8 surface loop coils. To allow imaging of both sides of the neck, the RF array is divided into 2 coil clusters, each with 4 overlapping loop elements. For safety validation, numerical computations of the RF field distribution and the corresponding specific absorption rate were performed on the basis of a heterogeneous human body model. To validate the coil model, maps of the transmit B1+ field were compared between simulation and measurement. In vivo images of a healthy volunteer and a patient (ulcerating plaque and a 50% stenosis of the right internal carotid artery) were acquired using a 3-dimensional FLASH sequence with a high isotropic spatial resolution of 0.54 mm as well as using pulse-triggered proton density (PD)/T2-weighted turbo spin echo sequences. Results: Measurements of the S-parameters yielded a reflection and isolation of the coil elements of better than −18 and −13 dB, respectively. Measurements of the g-factor indicated good image quality for parallel imaging acceleration factors up to 2.4. A similar distribution and a very good match of the absolute values were found between the measured and simulated B1+ transmit RF field for the validation of the coil model. In vivo images revealed good signal excitation of both sides of the neck and a high vessel-to-background image contrast for the noncontrast-enhanced 3-dimensional FLASH sequence. Imaging at 7 T could depict the extent of stenosis, and revealed the disruption and ulcer of the plaque. Conclusions: This study demonstrates that 2 four-channel transmit/receive RF arrays for each side of the neck is a suitable concept for in vivo MRI of the carotid arteries at 7 Tesla. Further studies are needed to explore and exploit the full potential of 7 T high-field MRI for carotid atherosclerotic plaque imaging. Y1 - 2011 U6 - https://doi.org/10.1097/RLI.0b013e318206cee4 SN - 1536-0210 VL - 46 IS - 4 SP - 246 EP - 254 PB - Wolters Kluwer CY - Köln ER - TY - JOUR A1 - Selmer, Thorsten A1 - Thamer, Wiebke A1 - Cirpus, Irina A1 - Hans, Marcus T1 - A two [4Fe-4S]-cluster-containing ferredoxin as an alternative electron donor for 2-hydroxyglutaryl-CoA dehydratase from Acidaminococcus fermentans / Thamer, Wiebke ; Cirpus, Irina ; Hans, Marcus ; Pierik, Antonio, J. ; Selmer, Thorsten ; Bill, Eckhard ; JF - Archives of Microbiology. 179 (2003), H. 3 Y1 - 2003 SN - 1432-072X SP - 197 EP - 204 ER - TY - JOUR A1 - Kühn, Raoul-Roman A1 - Haugner, Werner A1 - Staat, Manfred A1 - Sponagel, Stefan T1 - A Two Phase Mixture Model based on Bone Observation N2 - An optimization method is developed to describe the mechanical behaviour of the human cancellous bone. The method is based on a mixture theory. A careful observation of the behaviour of the bone material leads to the hypothesis that the bone density is controlled by the principal stress trajectories (Wolff’s law). The basic idea of the developed method is the coupling of a scalar value via an eigenvalue problem to the principal stress trajectories. On the one hand this theory will permit a prediction of the reaction of the biological bone structure after the implantation of a prosthesis, on the other hand it may be useful in engineering optimization problems. An analytical example shows its efficiency. KW - Knochen KW - Knochenbildung KW - Knochenchirugie KW - Strukturanalyse KW - Schwammknochen KW - Knochendichte KW - Wolffsches Gesetz KW - bone structure KW - bone density KW - Wolff's Law KW - cancellous bone Y1 - 2004 ER - TY - JOUR A1 - Hardt, Arno A1 - Köhler, M. A1 - Müller, K. D. A1 - Stoff, H. T1 - A two-dimensional position sensitive charged-particle detector for the magnetic spectrograph "BIG KARL" of the Jülich Cyclotron "JULIC". M. Köhler, K. D. Müller, H. Stoff, M. Teske, G. P. A. Berg, A. Hardt, S. Martin, C. Mayer-Böricke , J. Meißburger JF - Nuclear Instruments and Methods. 75 (1980), H. 2-3 Y1 - 1980 SN - 0029-554X SP - 357 EP - 362 ER - TY - JOUR A1 - Faßbender, Heinz A1 - Vogler, Heiko T1 - A universal unification algorithm based on unification-driven leftmost outermost narrowing JF - Acta Cybernetica. 11 (1994), H. 3 Y1 - 1994 SN - 0324-721x SP - 139 EP - 167 ER - TY - JOUR A1 - Faßbender, Heinz T1 - A verified implementation of narrowing JF - Programming languages: implementations, logics and programs : proceedings / 7th International Symposium, PLILP '95, Utrecht, The Netherlands, September 20 - 22, 1995. Manuel Hermenegildo ... (ed.) Y1 - 1995 SN - 3-540-60359-X N1 - (Lecture notes in computer science ; 982) SP - 63 EP - 80 PB - Springer CY - Berlin [u.a.] ER - TY - JOUR A1 - Stock, J. A1 - Malindretos, J. A1 - Indlekofer, K.M. A1 - Pöttgens, Michael A1 - Förster, Arnold A1 - Lüth, Hans T1 - A Vertical Resonant Tunneling Transistor for Application in Digital Logic Circuits JF - IEEE Transactions on Electron Devices (T-ED). 48 (2001), H. 6 Y1 - 2001 SN - 0018-9383 SP - 1028 EP - 1032 ER - TY - JOUR A1 - Bergmann, Sandra A1 - Demuth, Bastian A1 - Sander, Volker T1 - A Web Framework for Workflow Submission and Monitoring via UNICORE 6 based on Distributable Scientific Workflow Templates JF - UNICORE Summit 2011 : proceedings, 7-8 July 2011, Torun, Poland / Mathilde Romberg ... (Eds.) Y1 - 2011 SN - 9783893367504 N1 - UNICORE Summit ; (2011 ; 2011.07.07-08 ; Torun) ; Schriften des Forschungszentrums Jülich IAS Series 9 SP - 45 EP - 50 PB - Forschungszentrum Jülich CY - Jülich ER - TY - JOUR A1 - Simonis, A. A1 - Krings, T. A1 - Lüth, H. A1 - Wang, J. A1 - Schöning, Michael Josef T1 - A „hybrid“ thin-film pH sensor with integrated thick-film reference JF - Sensors. 1 (2001), H. 6 Y1 - 2001 SN - 1424-8220 SP - 183 EP - 192 ER - TY - JOUR A1 - Golland, Alexander A1 - Engling, Christoph T1 - a-i3/BSI Symposium 2014: Sicherheit von Daten und Identitäten angesichts NSA und Big Data JF - DSB Datenschutz-Berater Y1 - 2014 SN - 0170-7256 VL - 38 IS - 7-8 SP - 165 EP - 166 PB - DFV Mediengruppe CY - Frankfurt a.M. ER -