@article{ZhangValeroBungetal.2018, author = {Zhang, G. and Valero, Daniel and Bung, Daniel Bernhard and Chanson, H.}, title = {On the estimation of free-surface turbulence using ultrasonic sensors}, series = {Flow Measurement and Instrumentation}, volume = {60}, journal = {Flow Measurement and Instrumentation}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0955-5986}, doi = {10.1016/j.flowmeasinst.2018.02.009}, pages = {171 -- 184}, year = {2018}, abstract = {Accurate determination of free-surface dynamics has attracted much research attention during the past decade and has important applications in many environmental and water related areas. In this study, the free-surface dynamics in several turbulent flows commonly found in nature were investigated using a synchronised setup consisting of an ultrasonic sensor and a high-speed video camera. Basic sensor capabilities were examined in dry conditions to allow for a better characterisation of the present sensor model. The ultrasonic sensor was found to adequately reproduce free-surface dynamics up to the second order, especially in two-dimensional scenarios with the most energetic modes in the low frequency range. The sensor frequency response was satisfactory in the sub-20 Hz band, and its signal quality may be further improved by low-pass filtering prior to digitisation. The application of the USS to characterise entrapped air in high-velocity flows is also discussed.}, language = {en} } @article{SommerGerlingPredel1984, author = {Sommer, Ferdinand and Gerling, Ulrich and Predel, Bruno}, title = {On the evaluation of interchange energies and the equilibrium-constant from mixing enthalpies of a regular associated solution-comment}, series = {Zeitschrift f{\"u}r Metallkunde : international journal of materials research and advanced techniques. Bd. 75, H. 11}, journal = {Zeitschrift f{\"u}r Metallkunde : international journal of materials research and advanced techniques. Bd. 75, H. 11}, issn = {0044-3093 ; 0179-4841}, pages = {898}, year = {1984}, language = {en} } @article{ZastrowHackl1988, author = {Zastrow, Udo and Hackl, Klaus}, title = {On the existence, uniqueness and completeness of displacements and stress functions in linear elasticity / Hackl, Klaus ; Zastrow, Udo}, series = {Journal of Elasticity. 19 (1988), H. 1}, journal = {Journal of Elasticity. 19 (1988), H. 1}, isbn = {1573-2681}, pages = {3 -- 23}, year = {1988}, language = {en} } @article{GoettenFingerHavermannetal.2018, author = {G{\"o}tten, Falk and Finger, Felix and Havermann, Marc and Braun, Carsten and Gomez, Francisco and Bill, C.}, title = {On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles}, series = {Deutscher Luft- und Raumfahrtkongress 2018}, journal = {Deutscher Luft- und Raumfahrtkongress 2018}, publisher = {DGLR}, address = {Bonn}, doi = {10.25967/480058}, pages = {11 S.}, year = {2018}, abstract = {The flight performance impact of three different landing gear configurations on a small, fixed-wing UAV is analyzed with a combination of RANS CFD calculations and an incremental flight performance algorithm. A standard fixed landing gear configuration is taken as a baseline, while the influence of retracting the landing gear or applying streamlined fairings is investigated. A retraction leads to a significant parasite drag reduction, while also fairings promise large savings. The increase in lift-to-drag ratio is reduced at high lift coefficients due to the influence of induced drag. All configurations are tested on three different design missions with an incremental flight performance algorithm. A trade-off study is performed using the retracted or faired landing gear's weight increase as a variable. The analysis reveals only small mission performance gains as the aerodynamic improvements are negated by weight penalties. A new workflow for decision-making is presented that allows to estimate if a change in landing gear configuration is beneficial for a small UAV.}, language = {en} } @article{Zastrow1985, author = {Zastrow, Udo}, title = {On the formulation of the fundamental solutions for orthotropic plane elasticity}, series = {Acta Mechanica. 57 (1985), H. 3-4}, journal = {Acta Mechanica. 57 (1985), H. 3-4}, isbn = {1619-6937}, pages = {113 -- 122}, year = {1985}, language = {en} } @article{FoersterMorvicBetko1998, author = {F{\"o}rster, Arnold and Morvic, M. and Betko, J.}, title = {On the hopping and band conductivity in molecular-beam epitaxial low-temperature grown GaAs / M. Morvic ; J. Betko ; J. Nov{\´a}k ... A. F{\"o}rster}, series = {Physica status solidi / B, Basic research. 205 (1998), H. 1}, journal = {Physica status solidi / B, Basic research. 205 (1998), H. 1}, isbn = {1521-3951}, pages = {125 -- 128}, year = {1998}, language = {en} } @article{MoehrenBergmannJanseretal.2023, author = {M{\"o}hren, Felix and Bergmann, Ole and Janser, Frank and Braun, Carsten}, title = {On the influence of elasticity on propeller performance: a parametric study}, series = {CEAS Aeronautical Journal}, volume = {14}, journal = {CEAS Aeronautical Journal}, publisher = {Springer Nature}, address = {Berlin}, issn = {1869-5590 (Online)}, doi = {10.1007/s13272-023-00649-y}, pages = {311 -- 323}, year = {2023}, abstract = {The aerodynamic performance of propellers strongly depends on their geometry and, consequently, on aeroelastic deformations. Knowledge of the extent of the impact is crucial for overall aircraft performance. An integrated simulation environment for steady aeroelastic propeller simulations is presented. The simulation environment is applied to determine the impact of elastic deformations on the aerodynamic propeller performance. The aerodynamic module includes a blade element momentum approach to calculate aerodynamic loads. The structural module is based on finite beam elements, according to Timoshenko theory, including moderate deflections. Several fixed-pitch propellers with thin-walled cross sections made of both isotropic and non-isotropic materials are investigated. The essential parameters are varied: diameter, disc loading, sweep, material, rotational, and flight velocity. The relative change of thrust between rigid and elastic blades quantifies the impact of propeller elasticity. Swept propellers of large diameters or low disc loadings can decrease the thrust significantly. High flight velocities and low material stiffness amplify this tendency. Performance calculations without consideration of propeller elasticity can lead to decreased efficiency. To avoid cost- and time-intense redesigns, propeller elasticity should be considered for swept planforms and low disc loadings.}, language = {en} } @article{BergmannMoehrenBraunetal.2023, author = {Bergmann, Ole and M{\"o}hren, Felix and Braun, Carsten and Janser, Frank}, title = {On the influence of elasticity on swept propeller noise}, series = {AIAA SCITECH 2023 Forum}, journal = {AIAA SCITECH 2023 Forum}, publisher = {AIAA}, address = {Reston, Va.}, doi = {10.2514/6.2023-0210}, year = {2023}, abstract = {High aerodynamic efficiency requires propellers with high aspect ratios, while propeller sweep potentially reduces noise. Propeller sweep and high aspect ratios increase elasticity and coupling of structural mechanics and aerodynamics, affecting the propeller performance and noise. Therefore, this paper analyzes the influence of elasticity on forward-swept, backward-swept, and unswept propellers in hover conditions. A reduced-order blade element momentum approach is coupled with a one-dimensional Timoshenko beam theory and Farassat's formulation 1A. The results of the aeroelastic simulation are used as input for the aeroacoustic calculation. The analysis shows that elasticity influences noise radiation because thickness and loading noise respond differently to deformations. In the case of the backward-swept propeller, the location of the maximum sound pressure level shifts forward by 0.5 °, while in the case of the forward-swept propeller, it shifts backward by 0.5 °. Therefore, aeroacoustic optimization requires the consideration of propeller deformation.}, language = {en} } @article{HelsperNiessner1985, author = {Helsper, Christoph and Nießner, R.}, title = {On the Influence of the Vapour Substance on the Behaviour of an Expansion Type Condensation Nucleus Counter}, series = {Journal of Aerosol Science. 16 (1985), H. 5}, journal = {Journal of Aerosol Science. 16 (1985), H. 5}, isbn = {0021-8502}, pages = {457 -- 461}, year = {1985}, language = {en} } @article{BlomeChuHoelletal.1988, author = {Blome, Hans-Joachim and Chu, Y. and Hoell, J and Priester, W.}, title = {On the observational discrimination of Friedmann-Lema{\^i}tre models}, series = {Large Scale Structures of the Universe: Proceedings of the 130th Symposium of the International Astronomical Union, dedicated to the memory of Marc A. Aaronson (1950-1987) held in Balatonfured, Hungary, June 15-20, 1987. Edited by Jean Audouze, Marie-Christine Pelletan and Sandor Szalay.}, journal = {Large Scale Structures of the Universe: Proceedings of the 130th Symposium of the International Astronomical Union, dedicated to the memory of Marc A. Aaronson (1950-1987) held in Balatonfured, Hungary, June 15-20, 1987. Edited by Jean Audouze, Marie-Christine Pelletan and Sandor Szalay.}, publisher = {Kluwer Academic Publishers}, address = {Dordrecht}, isbn = {90-277-2742-2}, pages = {517}, year = {1988}, language = {en} } @article{SchneiderTran2015, author = {Schneider, Felix and Tran, Duc Hung}, title = {On the relation between the fair value option and bid-ask spreads: descriptive evidence on the recognition of credit risk changes under IFRS}, series = {Journal of Business Economics}, volume = {85}, journal = {Journal of Business Economics}, number = {9}, publisher = {Springer}, address = {Berlin}, issn = {1861-8928}, doi = {10.1007/s11573-015-0776-2}, pages = {1049 -- 1081}, year = {2015}, language = {en} } @article{YangKriechbaumerAlbrachtetal.2015, author = {Yang, Peng-Fei and Kriechbaumer, Andreas and Albracht, Kirsten and Sanno, Maximilian and Ganse, Bergita and Koy, Timmo and Shang, Peng and Br{\"u}ggemann, Gert-Peter and M{\"u}ller, Lars Peter and Rittweger, J{\"o}rn}, title = {On the relationship between tibia torsional deformation and regional muscle contractions in habitual human exercises in vivo}, series = {Journal of Biomechanics}, volume = {48}, journal = {Journal of Biomechanics}, number = {3}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0021-9290}, doi = {10.1016/j.jbiomech.2014.12.031}, pages = {456 -- 464}, year = {2015}, language = {en} } @article{Stulpe1998, author = {Stulpe, Werner}, title = {On the Representation of Quantum Mechanics on a Classical Sample Space}, series = {International Journal of Theoretical Physics. 37 (1998), H. 1}, journal = {International Journal of Theoretical Physics. 37 (1998), H. 1}, isbn = {1572-9575}, pages = {349 -- 356}, year = {1998}, language = {en} } @article{Stulpe1992, author = {Stulpe, Werner}, title = {On the Representation of Quantum Mechanics on Phase Space}, series = {International Journal of Theoretical Physics. 31 (1992), H. 9}, journal = {International Journal of Theoretical Physics. 31 (1992), H. 9}, isbn = {1572-9575}, pages = {1785 -- 1795}, year = {1992}, language = {en} } @article{ZatkoDubeckyBohaceketal.2004, author = {Zatko, B. and Dubeck{\´y}, F. and Bohacek, P. and Gombia, E. and Frigeri, P. and Mosca, R. and Franchi, S. and Huarn, J. and Nescas, V. and Sekacova, M. and F{\"o}rster, Arnold and Kordos, P.}, title = {On the spectrometric performance limit of radiation detectors based on semi-insulating GaAs}, series = {Nuclear instruments and methods in physics research, Section A. 531 (2004), H. 1-2}, journal = {Nuclear instruments and methods in physics research, Section A. 531 (2004), H. 1-2}, isbn = {0168-9002}, pages = {111 -- 120}, year = {2004}, language = {en} } @article{ReisselQuell1996, author = {Reißel, Martin and Quell, P.}, title = {On the Vanishing Displacement Current Limit for Eddy-Current Problems / Quell, P. ; Reißel, M.}, series = {ZAMM - Zeitschrift f{\"u}r Angewandte Mathematik und Mechanik. 76 (1996), H. S2}, journal = {ZAMM - Zeitschrift f{\"u}r Angewandte Mathematik und Mechanik. 76 (1996), H. S2}, isbn = {0044-2267}, pages = {649 -- 650}, year = {1996}, language = {en} } @article{FerreinSteinbauer2010, author = {Ferrein, Alexander and Steinbauer, Gerald}, title = {On the Way to High-Level Programming for Resource-Limited Embedded Systems with Golog}, series = {Simulation, Modeling, and Programming for Autonomous Robots}, journal = {Simulation, Modeling, and Programming for Autonomous Robots}, pages = {229 -- 240}, year = {2010}, language = {en} } @article{PieronekKleefeld2024, author = {Pieronek, Lukas and Kleefeld, Andreas}, title = {On trajectories of complex-valued interior transmission eigenvalues}, series = {Inverse problems and imaging : IPI}, volume = {18}, journal = {Inverse problems and imaging : IPI}, number = {2}, publisher = {AIMS}, address = {Springfield, Mo}, issn = {1930-8337 (Print)}, doi = {10.3934/ipi.2023041}, pages = {480 -- 516}, year = {2024}, abstract = {This paper investigates the interior transmission problem for homogeneous media via eigenvalue trajectories parameterized by the magnitude of the refractive index. In the case that the scatterer is the unit disk, we prove that there is a one-to-one correspondence between complex-valued interior transmission eigenvalue trajectories and Dirichlet eigenvalues of the Laplacian which turn out to be exactly the trajectorial limit points as the refractive index tends to infinity. For general simply-connected scatterers in two or three dimensions, a corresponding relation is still open, but further theoretical results and numerical studies indicate a similar connection.}, language = {en} } @article{FoersterZamdmerHuetal.1999, author = {F{\"o}rster, Arnold and Zamdmer, N. and Hu, Qing and McIntosh, K. A.}, title = {On-chip frequency domain submillimeter-wave transceiver. Zamdmer, N.; Hu, Qing ; McIntosh K. A. ; Verghise, S. ; F{\"o}rster, A.}, series = {Applied Physics Letters. 75 (1999), H. 24}, journal = {Applied Physics Letters. 75 (1999), H. 24}, isbn = {1077-3118}, pages = {3877 -- 3879}, year = {1999}, language = {en} } @article{HardtBisplinghoffErnstetal.1977, author = {Hardt, Arno and Bisplinghoff, J. and Ernst, J. and L{\"o}hr, R.}, title = {On-line apparatus BANDIT for half-life determination of short-lived neutron deficient isotopes. A. Hardt, J. Bisplinghoff, J. Ernst, R. L{\"o}hr, H. Machner, T . Mayer-Kuckuk}, series = {Nuclear Instruments and Methods. 143 (1977), H. 3}, journal = {Nuclear Instruments and Methods. 143 (1977), H. 3}, isbn = {0029-554X}, pages = {519 -- 523}, year = {1977}, language = {en} }