TY - JOUR A1 - Ahmed, Essam A1 - Reisgen, Uwe A1 - Schleser, Markus A1 - Mokrov, Oleg T1 - On formability of tailor laser welded blanks of DP/TRIP steel sheets JF - Science and technology of welding and joining N2 - This paper aims to evaluate the formability of tailor welded blanks of dual phase (DP600)/transformation induced plasticity (TRIP700) steel sheets. In this work, bead on plate butt joints of 2·5 mm DP600 and 1·2 mm TRIP700 steel sheets were performed using CO2 laser beam welding. Microhardness measurements and transverse tensile testing were carried out to characterise the welds. The formability of base metals and welds were investigated by standard Erichsen test. In a perpendicular tensile test to the weld line, all specimens were fractured at the TRIP base metal, and the strengths were somewhat higher than those of base metal. There was a significant reduction in formability caused by welding of the DP600/TRIP700 steel sheets, and the formability increased with increasing welding speed. Y1 - 2010 U6 - https://doi.org/10.1179/136217110X12731414739754 SN - 1743-2936 VL - 15 IS - 5 SP - 337 EP - 342 PB - Maney CY - Leeds ER - TY - JOUR A1 - Stulpe, Werner A1 - Bugajski, S. A1 - Hellwig, K.-E. T1 - On Fuzzy Random Variables and Statistical Maps. Bugajski, S.; Hellwig, K.-E.; Stulpe, W. JF - Reports on Mathematical Physics. 41 (1998), H. 1 Y1 - 1998 SN - 0034-4877 SP - 1 EP - 11 ER - TY - JOUR A1 - Baringhaus, Ludwig A1 - Gaigall, Daniel T1 - On Hotelling’s T² test in a special paired sample case JF - Communications in Statistics - Theory and Methods N2 - In a special paired sample case, Hotelling’s T² test based on the differences of the paired random vectors is the likelihood ratio test for testing the hypothesis that the paired random vectors have the same mean; with respect to a special group of affine linear transformations it is the uniformly most powerful invariant test for the general alternative of a difference in mean. We present an elementary straightforward proof of this result. The likelihood ratio test for testing the hypothesis that the covariance structure is of the assumed special form is derived and discussed. Applications to real data are given. KW - complete block symmetry KW - Hotelling’s T² test KW - likelihood ratio test KW - uniformly most powerful invariant test Y1 - 2017 U6 - https://doi.org/10.1080/03610926.2017.1408828 SN - 1532-415X VL - 48 IS - 2 SP - 257 EP - 267 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Schuba, Marko A1 - Reichl, Peter T1 - On large-scale reliable multicast protocols / Schuba, M. ; Reichl, P. JF - 6th IEE Conference on Telecommunications Y1 - 1998 SN - 0-85296-700-4 N1 - Conf. Publ. No. 451 SP - 133 EP - 137 ER - TY - JOUR A1 - Altherr, Lena A1 - Joggerst, Laura A1 - Leise, Philipp A1 - Pfetsch, Marc E. A1 - Schmitt, Andreas A1 - Wendt, Janine T1 - On obligations in the development process of resilient systems with algorithmic design methods JF - Applied Mechanics and Materials N2 - Advanced computational methods are needed both for the design of large systems and to compute high accuracy solutions. Such methods are efficient in computation, but the validation of results is very complex, and highly skilled auditors are needed to verify them. We investigate legal questions concerning obligations in the development phase, especially for technical systems developed using advanced methods. In particular, we consider methods of resilient and robust optimization. With these techniques, high performance solutions can be found, despite a high variety of input parameters. However, given the novelty of these methods, it is uncertain whether legal obligations are being met. The aim of this paper is to discuss if and how the choice of a specific computational method affects the developer’s product liability. The review of legal obligations in this paper is based on German law and focuses on the requirements that must be met during the design and development process. KW - legal obligations KW - product liability KW - design of technical systems KW - optimization KW - resilience Y1 - 2018 SN - 1662-7482 U6 - https://doi.org/10.4028/www.scientific.net/AMM.885.240 VL - 885 IS - 885 SP - 240 EP - 252 PB - Trans Tech Publications CY - Bäch ER - TY - JOUR A1 - Reißel, Martin A1 - Herbst, Michael A1 - Gottschalk, Swen A1 - Hardelauf, Horst T1 - On preconditioning for a parallel solution of the Richards equation / Herbst, Michael ; Gottschalk, Swen ; Reißel, Martin ; Hardelauf, Horst ; Kasteel, Roy ; Javaux, Matthieu ; Vanderborght, Jan ; Vereecken, Harry JF - Computers & Geosciences. 34 (2008), H. 12 Y1 - 2008 SN - 0098-3004 SP - 1958 EP - 1963 ER - TY - JOUR A1 - Dikta, Gerhard T1 - On Semiparametric Random Censorship Models JF - Journal of Statistical Planning and Inference. 66 (1998), H. 2 Y1 - 1998 SN - 0378-3758 SP - 253 EP - 279 ER - TY - JOUR A1 - Grotendorst, Johannes A1 - Jansen, Paul A1 - Schoberth, Siegfried T1 - On Solving the McConnell Equations in Biochemistry / Grotendorst, Johannes ; Jansen, Paul ; Schoberth, Siegfried JF - MapleTech. 1 (1993) Y1 - 1993 SN - 1061-5733 N1 - zgl. Technical Report KFA-ZAM-IB-9314 ; The Maple Technical Newsletter SP - 56 EP - 62 ER - TY - JOUR A1 - Gaigall, Daniel T1 - On the applicability of several tests to models with not identically distributed random effects JF - Statistics : A Journal of Theoretical and Applied Statistics N2 - We consider Kolmogorov–Smirnov and Cramér–von-Mises type tests for testing central symmetry, exchangeability, and independence. In the standard case, the tests are intended for the application to independent and identically distributed data with unknown distribution. The tests are available for multivariate data and bootstrap procedures are suitable to obtain critical values. We discuss the applicability of the tests to random effects models, where the random effects are independent but not necessarily identically distributed and with possibly unknown distributions. Theoretical results show the adequacy of the tests in this situation. The quality of the tests in models with random effects is investigated by simulations. Empirical results obtained confirm the theoretical findings. A real data example illustrates the application. KW - central symmetry test KW - exchangeability test KW - independence test KW - random effects KW - not identically distributed Y1 - 2023 SN - 0323-3944 U6 - https://doi.org/10.1080/02331888.2023.2193748 SN - 1029-4910 VL - 57 PB - Taylor & Francis CY - London ER - TY - JOUR A1 - Zastrow, Udo T1 - On the complete system of fundamental solutions for anisotropic slices and slabs: A comparison by use of the slab analogy JF - Journal of Elasticity. 15 (1985), H. 3 Y1 - 1985 SN - 1573-2681 SP - 293 EP - 318 ER - TY - JOUR A1 - Dankelmann, Peter A1 - Hellwig, Angelika A1 - Volkmann, Lutz T1 - On the connectivity of diamond-free graphs JF - Discrete applied mathematics Y1 - 2007 SN - 0166-218X (E-Journal); 1872-6771 (E-Journal); 0166-218X (Print) VL - Vol. 155 IS - Iss. 16 SP - 2111 EP - 2117 ER - TY - JOUR A1 - Heuermann, Holger A1 - Sadeghfam, Arash T1 - On the design of multimode integrated circuits in multilayered processes / Sadeghfam, A. ; Heuermann, H. JF - European Microwave Conference, 2007, 9-12 Oct. 2007 Y1 - 2007 SN - 978-2-87487-001-9 N1 - EuMC 2007 ; European Microwave Conference ; (37 : ; 2007.10.09-12 : ; Munich) SP - 516 EP - 519 ER - TY - JOUR A1 - Weigand, Christoph T1 - On the Effects of SPC on Production Time JF - Economic Quality Control. 8 (1993) Y1 - 1993 SN - 0940-5151 SP - 23 EP - 61 ER - TY - JOUR A1 - Zhang, G. A1 - Valero, Daniel A1 - Bung, Daniel Bernhard A1 - Chanson, H. T1 - On the estimation of free-surface turbulence using ultrasonic sensors JF - Flow Measurement and Instrumentation N2 - 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. Y1 - 2018 U6 - https://doi.org/10.1016/j.flowmeasinst.2018.02.009 SN - 0955-5986 VL - 60 SP - 171 EP - 184 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Sommer, Ferdinand A1 - Gerling, Ulrich A1 - Predel, Bruno T1 - On the evaluation of interchange energies and the equilibrium-constant from mixing enthalpies of a regular associated solution-comment JF - Zeitschrift für Metallkunde : international journal of materials research and advanced techniques. Bd. 75, H. 11 Y1 - 1984 SN - 0044-3093 ; 0179-4841 SP - 898 ER - TY - JOUR A1 - Zastrow, Udo A1 - Hackl, Klaus T1 - On the existence, uniqueness and completeness of displacements and stress functions in linear elasticity / Hackl, Klaus ; Zastrow, Udo JF - Journal of Elasticity. 19 (1988), H. 1 Y1 - 1988 SN - 1573-2681 SP - 3 EP - 23 ER - TY - JOUR A1 - Götten, Falk A1 - Finger, Felix A1 - Havermann, Marc A1 - Braun, Carsten A1 - Gomez, Francisco A1 - Bill, C. T1 - On the flight performance impact of landing gear drag reduction methods for unmanned air vehicles JF - Deutscher Luft- und Raumfahrtkongress 2018 N2 - 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. Y1 - 2018 U6 - https://doi.org/10.25967/480058 PB - DGLR CY - Bonn ER - TY - JOUR A1 - Zastrow, Udo T1 - On the formulation of the fundamental solutions for orthotropic plane elasticity JF - Acta Mechanica. 57 (1985), H. 3-4 Y1 - 1985 SN - 1619-6937 SP - 113 EP - 122 ER - TY - JOUR A1 - Förster, Arnold A1 - Morvic, M. A1 - Betko, J. T1 - On the hopping and band conductivity in molecular-beam epitaxial low-temperature grown GaAs / M. Morvic ; J. Betko ; J. Novák ... A. Förster JF - Physica status solidi / B, Basic research. 205 (1998), H. 1 Y1 - 1998 SN - 1521-3951 SP - 125 EP - 128 ER - TY - JOUR A1 - Möhren, Felix A1 - Bergmann, Ole A1 - Janser, Frank A1 - Braun, Carsten T1 - On the influence of elasticity on propeller performance: a parametric study JF - CEAS Aeronautical Journal N2 - 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. KW - Propeller KW - Finite element method KW - Blade element method KW - Propeller elasticity KW - Aeroelasticity Y1 - 2023 U6 - https://doi.org/10.1007/s13272-023-00649-y SN - 1869-5590 (Online) SN - 1869-5582 (Print) N1 - Corresponding author: Felix Möhren VL - 14 SP - 311 EP - 323 PB - Springer Nature CY - Berlin ER -