@article{BeckenbachScheidweiler2016, author = {Beckenbach, Isabel and Scheidweiler, Robert}, title = {Perfect ƒ-Matchings and ƒ-Factors in Hypergraphs - A Combinatorial Approach}, series = {Discrete Mathematics}, volume = {240}, journal = {Discrete Mathematics}, number = {10}, publisher = {Elsevier}, address = {Amsterdam}, issn = {2192-7782}, doi = {10.1016/j.disc.2017.05.005}, pages = {2499 -- 2506}, year = {2016}, abstract = {We prove characterizations of the existence of perfect ƒ-matchings in uniform mengerian and perfect hypergraphs. Moreover, we investigate the ƒ-factor problem in balanced hypergraphs. For uniform balanced hypergraphs we prove two existence theorems with purely combinatorial arguments, whereas for non-uniform balanced hypergraphs we show that the ƒ-factor problem is NP-hard.}, language = {en} } @article{ScholzRomagnoliDachwaldetal.2011, author = {Scholz, Christina and Romagnoli, Daniele and Dachwald, Bernd and Theil, Stephan}, title = {Performance analysis of an attitude control system for solar sails using sliding masses}, series = {Advances in Space Research}, volume = {48}, journal = {Advances in Space Research}, number = {11}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0273-1177}, pages = {1822 -- 1835}, year = {2011}, language = {en} } @article{FiedlerOrzadaFloeseretal.2021, author = {Fiedler, Thomas M. and Orzada, Stephan and Fl{\"o}ser, Martina and Rietsch, Stefan H. G. and Quick, Harald H. and Ladd, Mark E. and Bitz, Andreas}, title = {Performance analysis of integrated RF microstrip transmit antenna arrays with high channel count for body imaging at 7 T}, series = {NMR in Biomedicine}, volume = {34}, journal = {NMR in Biomedicine}, number = {7}, publisher = {Wiley}, address = {Weinheim}, issn = {0952-3480 (ISSN)}, doi = {10.1002/nbm.4515}, pages = {18 SeitenWiley}, year = {2021}, abstract = {The aim of the current study was to investigate the performance of integrated RF transmit arrays with high channel count consisting of meander microstrip antennas for body imaging at 7 T and to optimize the position and number of transmit ele- ments. RF simulations using multiring antenna arrays placed behind the bore liner were performed for realistic exposure conditions for body imaging. Simulations were performed for arrays with as few as eight elements and for arrays with high channel counts of up to 48 elements. The B1+ field was evaluated regarding the degrees of freedom for RF shimming in the abdomen. Worst-case specific absorption rate (SARwc ), SAR overestimation in the matrix compression, the number of virtual obser- vation points (VOPs) and SAR efficiency were evaluated. Constrained RF shimming was performed in differently oriented regions of interest in the body, and the devia- tion from a target B1+ field was evaluated. Results show that integrated multiring arrays are able to generate homogeneous B1+ field distributions for large FOVs, espe- cially for coronal/sagittal slices, and thus enable body imaging at 7 T with a clinical workflow; however, a low duty cycle or a high SAR is required to achieve homoge- neous B1+ distributions and to exploit the full potential. In conclusion, integrated arrays allow for high element counts that have high degrees of freedom for the pulse optimization but also produce high SARwc , which reduces the SAR accuracy in the VOP compression for low-SAR protocols, leading to a potential reduction in array performance. Smaller SAR overestimations can increase SAR accuracy, but lead to a high number of VOPs, which increases the computational cost for VOP evaluation and makes online SAR monitoring or pulse optimization challenging. Arrays with interleaved rings showed the best results in the study.}, language = {en} } @article{GutheilBergGrotendorst2012, author = {Gutheil, Inge and Berg, Tommy and Grotendorst, Johannes}, title = {Performance Analysis of Parallel Eigensolvers of two Libraries on BlueGene/P}, series = {Journal of Mathematics and Systems Science}, volume = {2}, journal = {Journal of Mathematics and Systems Science}, number = {4}, publisher = {David Publishing}, address = {Libertyville}, issn = {2159-5291}, doi = {10.17265/2159-5291/2012.04.003}, pages = {231 -- 236}, year = {2012}, abstract = {Many applications in computational science and engineering require the computation of eigenvalues and vectors of dense symmetric or Hermitian matrices. For example, in DFT (density functional theory) calculations on modern supercomputers 10\% to 30\% of the eigenvalues and eigenvectors of huge dense matrices have to be calculated. Therefore, performance and parallel scaling of the used eigensolvers is of upmost interest. In this article different routines of the linear algebra packages ScaLAPACK and Elemental for parallel solution of the symmetric eigenvalue problem are compared concerning their performance on the BlueGene/P supercomputer. Parameters for performance optimization are adjusted for the different data distribution methods used in the two libraries. It is found that for all test cases the new library Elemental which uses a two-dimensional element by element distribution of the matrices to the processors shows better performance than the old ScaLAPACK library which uses a block-cyclic distribution.}, language = {en} } @article{Schuba1999, author = {Schuba, Marko}, title = {Performance Analysis of Reliable Multicast Mechanisms for Widely Spread Distributed Applications in the Internet}, series = {International Conference on Parallel and Distributed Processing Techniques and Applications : PDPTA '99 ; June 28 - July 1, 1999, Las Vegas, Nevada, USA / ed.: Hamid R. Arabnia}, journal = {International Conference on Parallel and Distributed Processing Techniques and Applications : PDPTA '99 ; June 28 - July 1, 1999, Las Vegas, Nevada, USA / ed.: Hamid R. Arabnia}, isbn = {1892512157}, pages = {1 -- 7}, year = {1999}, language = {en} } @article{HavermannBeylich1997, author = {Havermann, Marc and Beylich, A. E.}, title = {Performance and Limitations of the Laser-Induced Fluorescence Measurement Technique and the Established Experimental Methods for the Study of Supersonic Mixing / Havermann, M. ; Beylich, A. E.}, series = {International Journal of heat and technology. 15 (1997), H. 2}, journal = {International Journal of heat and technology. 15 (1997), H. 2}, publisher = {-}, pages = {3 -- 10}, year = {1997}, language = {en} } @article{FiedlerOrzadaFloeseretal.2022, author = {Fiedler, Thomas M. and Orzada, Stephan and Fl{\"o}ser, Martina and Rietsch, Stefan H. G. and Schmidt, Simon and Stelter, Jonathan K. and Wittrich, Marco and Quick, Harald H. and Bitz, Andreas and Ladd, Mark E.}, title = {Performance and safety assessment of an integrated transmit array for body imaging at 7 T under consideration of specificabsorption rate, tissue temperature, and thermal dose}, series = {NMR in Biomedicine}, volume = {35}, journal = {NMR in Biomedicine}, number = {5}, publisher = {Wiley}, issn = {0952-3480 (Print)}, doi = {10.1002/nbm.4656}, pages = {1 -- 17}, year = {2022}, abstract = {In this study, the performance of an integrated body-imaging array for 7 T with 32 radiofrequency (RF) channels under consideration of local specific absorption rate (SAR), tissue temperature, and thermal dose limits was evaluated and the imaging performance was compared with a clinical 3 T body coil. Thirty-two transmit elements were placed in three rings between the bore liner and RF shield of the gradient coil. Slice-selective RF pulse optimizations for B1 shimming and spokes were performed for differently oriented slices in the body under consideration of realistic constraints for power and local SAR. To improve the B1+ homogeneity, safety assessments based on temperature and thermal dose were performed to possibly allow for higher input power for the pulse optimization than permissible with SAR limits. The results showed that using two spokes, the 7 T array outperformed the 3 T birdcage in all the considered regions of interest. However, a significantly higher SAR or lower duty cycle at 7 T is necessary in some cases to achieve similar B1+ homogeneity as at 3 T. The homogeneity in up to 50 cm-long coronal slices can particularly benefit from the high RF shim performance provided by the 32 RF channels. The thermal dose approach increases the allowable input power and the corresponding local SAR, in one example up to 100 W/kg, without limiting the exposure time necessary for an MR examination. In conclusion, the integrated antenna array at 7 T enables a clinical workflow for body imaging and comparable imaging performance to a conventional 3 T clinical body coil.}, language = {en} } @article{BayonValeroGarciaBartualetal.2016, author = {Bayon, Arnau and Valero, Daniel and Garcia-Bartual, Rafael and Vall{\´e}s-Mor{\´a}n, Francisco Jos{\´e} and L{\´o}pez-Jim{\´e}nez, P. Amparo}, title = {Performance assessment of OpenFOAM and FLOW-3D in the numerical modeling of a low Reynolds number hydraulic jump}, series = {Environmental Modelling \& Software}, volume = {80}, journal = {Environmental Modelling \& Software}, publisher = {Elsevier}, address = {Amsterdam}, isbn = {1364-8152}, doi = {10.1016/j.envsoft.2016.02.018}, pages = {322 -- 335}, year = {2016}, abstract = {A comparative performance analysis of the CFD platforms OpenFOAM and FLOW-3D is presented, focusing on a 3D swirling turbulent flow: a steady hydraulic jump at low Reynolds number. Turbulence is treated using RANS approach RNG k-ε. A Volume Of Fluid (VOF) method is used to track the air-water interface, consequently aeration is modeled using an Eulerian-Eulerian approach. Structured meshes of cubic elements are used to discretize the channel geometry. The numerical model accuracy is assessed comparing representative hydraulic jump variables (sequent depth ratio, roller length, mean velocity profiles, velocity decay or free surface profile) to experimental data. The model results are also compared to previous studies to broaden the result validation. Both codes reproduced the phenomenon under study concurring with experimental data, although special care must be taken when swirling flows occur. Both models can be used to reproduce the hydraulic performance of energy dissipation structures at low Reynolds numbers.}, language = {en} } @article{SchubaHaverkortSchneider2000, author = {Schuba, Marko and Haverkort, Boudewijn R. and Schneider, Gaby}, title = {Performance evaluation of multicast communication in packet-switched networks / Schuba, Marko ; Haverkort, Boudewijn R. ; Schneider, Gaby}, series = {Performance Evaluation. 39 (2000), H. 1-4}, journal = {Performance Evaluation. 39 (2000), H. 1-4}, isbn = {0166-5316}, pages = {61 -- 80}, year = {2000}, language = {en} } @article{BraunChengDoweyetal.2021, author = {Braun, Sebastian and Cheng, Chi-Tsun and Dowey, Steve and Wollert, J{\"o}rg}, title = {Performance evaluation of skill-based order-assignment in production environments with multi-agent systems}, series = {IEEE Journal of Emerging and Selected Topics in Industrial Electronics}, journal = {IEEE Journal of Emerging and Selected Topics in Industrial Electronics}, number = {Early Access}, publisher = {IEEE}, address = {New York}, issn = {2687-9735}, doi = {10.1109/JESTIE.2021.3108524}, year = {2021}, abstract = {The fourth industrial revolution introduces disruptive technologies to production environments. One of these technologies are multi-agent systems (MASs), where agents virtualize machines. However, the agent's actual performances in production environments can hardly be estimated as most research has been focusing on isolated projects and specific scenarios. We address this gap by implementing a highly connected and configurable reference model with quantifiable key performance indicators (KPIs) for production scheduling and routing in single-piece workflows. Furthermore, we propose an algorithm to optimize the search of extrema in highly connected distributed systems. The benefits, limits, and drawbacks of MASs and their performances are evaluated extensively by event-based simulations against the introduced model, which acts as a benchmark. Even though the performance of the proposed MAS is, on average, slightly lower than the reference system, the increased flexibility allows it to find new solutions and deliver improved factory-planning outcomes. Our MAS shows an emerging behavior by using flexible production techniques to correct errors and compensate for bottlenecks. This increased flexibility offers substantial improvement potential. The general model in this paper allows the transfer of the results to estimate real systems or other models.}, language = {en} } @article{HoffschmidtTellezValverdeetal.2003, author = {Hoffschmidt, Bernhard and T{\´e}llez, F{\´e}lix M. and Valverde, Antonio and Fernandez, Valerio and Fernandez, Jesus}, title = {Performance evaluation of the 200-kWth HiTRec-II open volumetric air receiver}, series = {Journal of solar energy engineering}, volume = {Vol. 125}, journal = {Journal of solar energy engineering}, number = {Iss. 1}, pages = {87 -- 94}, year = {2003}, language = {en} } @article{JacobsQuernheimAghadavoodiJolfaei1991, author = {Jacobs, Stephan and Quernheim, Ulrich and Aghadavoodi Jolfaei, Masoud}, title = {Performance Evalutation of three Access Protocols for VSAT Networks / Ulrich Quernheim, Stephan Jacobs, Masoud Aghadavoodi Jolfaei}, series = {Proceedings of the second European Conference on Satellite Communications : ECSC-2 ; Palais de Congr{\`e}s, Li{\`e}ge, Belgium, 22 - 24 October 1991 / [ed.: Brigitte Kaldeich]}, journal = {Proceedings of the second European Conference on Satellite Communications : ECSC-2 ; Palais de Congr{\`e}s, Li{\`e}ge, Belgium, 22 - 24 October 1991 / [ed.: Brigitte Kaldeich]}, publisher = {ESA Publ. Div.}, address = {Noordwijk}, isbn = {92-9092-170-6}, pages = {XXXII, 533 S. : Ill., graph. Darst.}, year = {1991}, language = {en} } @article{SchubaHermanns1995, author = {Schuba, Marko and Hermanns, Oliver}, title = {Performance Investigations of the IP Multicast Architecture / Hermanns, Oliver ; Schuba, Marko}, series = {Performance of the IP Multicast Achitecture . Proceedings JENC 6. Proceedings of the 6th Joint European Networking Conference, Tel Aviv}, journal = {Performance of the IP Multicast Achitecture . Proceedings JENC 6. Proceedings of the 6th Joint European Networking Conference, Tel Aviv}, pages = {121-1 -- 121-8}, year = {1995}, language = {en} } @article{GoetzeBaerWinkelmannetal.2005, author = {Goetze, Sandra and Baer, Alexandra and Winkelmann, Silke and Nehlsen, Kristina and Seibler, Jost and Maass, Karin and Bode, J{\"u}rgen}, title = {Performance of genomic bordering elements at predefined genomic loci}, series = {Molecular and Cellular Biology}, volume = {25}, journal = {Molecular and Cellular Biology}, number = {6}, issn = {1098-5549}, doi = {10.1128/MCB.25.6.2260-2272.2005}, pages = {2260 -- 2272}, year = {2005}, language = {en} } @article{FeuerriegelStahlberg1996, author = {Feuerriegel, Uwe and Stahlberg, R.}, title = {Performance of the Thermoselect Demonstration Plant at Fondotoce, Italy: Product Quality and Distribution of Chemical Elements in the Material Flow. Stahlberg, R. ; Feuerriegel, U.}, series = {Solid waste management: thermal treatment \& waste-to-energy technologies : proceedings of an international specialty conference sponsored by the Air \& Waste Management Association, [Washington, DC, April 18 - 21, 1995] / comp. by James D. Kilgroe}, journal = {Solid waste management: thermal treatment \& waste-to-energy technologies : proceedings of an international specialty conference sponsored by the Air \& Waste Management Association, [Washington, DC, April 18 - 21, 1995] / comp. by James D. Kilgroe}, publisher = {Air \& Waste Management Assoc.}, address = {Pittsburgh, Pa.}, pages = {XVI, 965 S : graph. Darst.}, year = {1996}, language = {en} } @article{LindemannRunge1997, author = {Lindemann, Markus and Runge, Alexander}, title = {Permanent IT-support in electronic commerce transactions}, series = {Electronic markets : the international journal of networked business. Vol. 7 (1997), iss. 1}, journal = {Electronic markets : the international journal of networked business. Vol. 7 (1997), iss. 1}, issn = {1422-8890}, pages = {18 -- 20}, year = {1997}, language = {en} } @article{AminTemizArtmannArtmannetal.2009, author = {Amin, Rashid and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard and Lazarovici, Philip and Lelkes, Peter I.}, title = {Permeability of an In Vitro Model of Blood Brain Barrier (BBB)}, series = {13th International Conference on Biomedical Engineering / Lim, Chwee Teck [Ed.]}, journal = {13th International Conference on Biomedical Engineering / Lim, Chwee Teck [Ed.]}, isbn = {978-3-540-92841-6}, pages = {81 -- 84}, year = {2009}, language = {en} } @article{KuchlerGuenthnerRibeiroetal.2023, author = {Kuchler, Timon and G{\"u}nthner, Roman and Ribeiro, Andrea and Hausinger, Renate and Streese, Lukas and W{\"o}hnl, Anna and Kesseler, Veronika and Negele, Johanna and Assali, Tarek and Carbajo-Lozoya, Javier and Lech, Maciej and Adorjan, Kristina and Stubbe, Hans Christian and Hanssen, Henner and Kotliar, Konstantin and Haller, Berhard and Heemann, Uwe and Schmaderer, Christoph}, title = {Persistent endothelial dysfunction in post-COVID-19 syndrome and its associations with symptom severity and chronic inflammation}, volume = {26}, publisher = {Springer Nature}, address = {Dordrecht}, doi = {10.1007/s10456-023-09885-6}, pages = {547 -- 563}, year = {2023}, abstract = {Background Post-COVID-19 syndrome (PCS) is a lingering disease with ongoing symptoms such as fatigue and cognitive impairment resulting in a high impact on the daily life of patients. Understanding the pathophysiology of PCS is a public health priority, as it still poses a diagnostic and treatment challenge for physicians. Methods In this prospective observational cohort study, we analyzed the retinal microcirculation using Retinal Vessel Analysis (RVA) in a cohort of patients with PCS and compared it to an age- and gender-matched healthy cohort (n = 41, matched out of n = 204). Measurements and main results PCS patients exhibit persistent endothelial dysfunction (ED), as indicated by significantly lower venular flicker-induced dilation (vFID; 3.42\% ± 1.77\% vs. 4.64\% ± 2.59\%; p = 0.02), narrower central retinal artery equivalent (CRAE; 178.1 [167.5-190.2] vs. 189.1 [179.4-197.2], p = 0.01) and lower arteriolar-venular ratio (AVR; (0.84 [0.8-0.9] vs. 0.88 [0.8-0.9], p = 0.007). When combining AVR and vFID, predicted scores reached good ability to discriminate groups (area under the curve: 0.75). Higher PCS severity scores correlated with lower AVR (R = - 0.37 p = 0.017). The association of microvascular changes with PCS severity were amplified in PCS patients exhibiting higher levels of inflammatory parameters. Conclusion Our results demonstrate that prolonged endothelial dysfunction is a hallmark of PCS, and impairments of the microcirculation seem to explain ongoing symptoms in patients. As potential therapies for PCS emerge, RVA parameters may become relevant as clinical biomarkers for diagnosis and therapy management.}, language = {en} } @article{SchaeferSchollGerschuetzetal.1994, author = {Sch{\"a}fer, Horst and Scholl, S. and Gersch{\"u}tz, F. and Fischer, A. (u.a.)}, title = {Persistent Photoconductivity in CdTe-based II-VI-Semiconductors}, series = {Solid State Communications. 91 (1994), H. 6}, journal = {Solid State Communications. 91 (1994), H. 6}, isbn = {0038-1098}, pages = {491 -- 495}, year = {1994}, language = {en} } @article{SchaeferSchollGerschuetzetal.1995, author = {Sch{\"a}fer, Horst and Scholl, S. and Gersch{\"u}tz, F. and Fischer, F. (u.a.)}, title = {Persistent Photoconductivity in Halogen-doped Cd1-X ZnX Te, Cd1-X MnX Te and Cd1-X-MgX -Te Layers}, series = {22nd International Conference on the Physics of Semiconductors : Vancouver, Canada, August 15 - 19, 1994 / ed. David J. Lockwood}, journal = {22nd International Conference on the Physics of Semiconductors : Vancouver, Canada, August 15 - 19, 1994 / ed. David J. Lockwood}, publisher = {World Scientific}, address = {Singapore [u.a.]}, isbn = {981-02-2021-9}, pages = {2423 -- 2426}, year = {1995}, language = {en} }