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991.
The guaranteed service model (GSM) computes optimal order-points in multi-echelon inventory control under the assumptions that delivery times can be guaranteed and the demand is bounded. Our new stochastic guaranteed service model (SGSM) with Recourse covers also scenarios that violate these assumptions. Simulation experiments on real-world data of a large German car manufacturer show that policies based on the SGSM dominate GSM-policies. 相似文献
992.
Konrad Pióro 《Central European Journal of Mathematics》2014,12(7):1052-1108
The aim of this paper is to characterize pairs (L, A), where L is a finite lattice and A a finite algebra, such that the subalgebra lattice of A is isomorphic to L. Next, necessary and sufficient conditions are found for pairs of finite algebras (of possibly distinct types) to have isomorphic subalgebra lattices. Both of these characterizations are particularly simple in the case of distributive subalgebra lattices. We do not restrict our attention to total algebras only, but we consider the more general case of partial algebras. Moreover, we use connections between algebras and hypergraphs to solve these problems. 相似文献
993.
Roland Beyer Arnd R. Junghans Peter Schillebeeckx Ivan Sirakov Tae-Yung Song Daniel Bemmerer Roberto Capote Anna Ferrari Andreas Hartmann Ronald Hannaske Jan Heyse Hyeon Il Kim Jong Woon Kim Toni Kögler Cheol Woo Lee Young-Ouk Lee Ralph Massarczyk Stefan E. Müller Tobias P. Reinhardt Marko Röder Konrad Schmidt Ronald Schwengner Tamás Szücs Marcell P. Takács Andreas Wagner Louis Wagner Sung-Chul Yang 《The European Physical Journal A - Hadrons and Nuclei》2018,54(5):81
994.
Edna Bode Antje K. Heinrich Merle Hirschmann Desalegne Abebew Yan‐Ni Shi Tien Duy Vo Frank Wesche Yi‐Ming Shi Peter Grün Svenja Simonyi Nadine Keller Yvonne Engel Sebastian Wenski Reuel Bennet Sophie Beyer Iris Bischoff Anthony Buaya Sophie Brandt Ibrahim Cakmak Harun imen Simone Eckstein Denia Frank Robert Fürst Martin Gand Gerd Geisslinger Selcuk Hazir Marina Henke Ralf Heermann Virginie Lecaudey Wilhelm Schfer Susanne Schiffmann Anja Schüffler Rebecca Schwenk Marisa Skaljac Eckhard Thines Marco Thines Thomas Ulshfer Andreas Vilcinskas Thomas A. Wichelhaus Helge B. Bode 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):19288-19288
995.
We predict the formation of a stable solitary rectangular pulse in semiconductor quantum dot media. The formation of such a pulse occurs when a quantum dot system is pumped in a way, where the s shell excitation exhibits gain while the p shell absorbs. We provide formulas to describe the rectangular pulse by the systems material parameters. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
996.
997.
D. Nickelsen A. Engel 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,82(3-4):207-218
We determine the complete asymptotic behaviour of the work distribution in driven stochastic systems described by Langevin equations. Special emphasis is put on the calculation of the pre-exponential factor which makes the result free of adjustable parameters. The method is applied to various examples and excellent agreement with numerical simulations is demonstrated. For the special case of parabolic potentials with time-dependent frequencies, we derive a universal functional form for the asymptotic work distribution. 相似文献
998.
Megha Patel Jiayun Zhong Konrad S. Gomez-Haibach Maria A. Gomez Graham King 《International journal of quantum chemistry》2020,120(20):e26356
Inspired by significant local distortions found near vacancies in a neutron pair distribution function analysis study (G. King et al., Inorg. Chem. 2012, 51, 13060) of Sr2 MSbO5.5 (M = Ca and Sr), this computational study finds minimum-energy structures with these and related distortions using density functional theory (DFT) with the Perdew-Burke-Ernzerhof (PBE) functional as implemented in the Vienna Ab Initio Simulations Package (VASP) (G. Kresse and J. Furthmüller, Phys. Rev. B, 1996, 54, 11169; G. Kresse and J. Hafner, Phys. Rev. B, 1993, 47, 558; G. Kresse and J. Furthmüller, Comput. Mater. Sci., 1996, 6, 15). All structures were optimized using the conjugate gradient method. The global minima found for both systems featured trigonal bipyramid SbO5 structures and edge sharing with M-centered polyhedra. However, while calcium ions occupied full and partial octahedra, the larger strontium ions were more commonly found in full and partial pentagonal bipyramids. Molecular dynamics with velocity rescaling at 1200 K revealed movements of the oxygen vacancy via polyhedral rotations. This work highlights the need to consider both square pyramid to trigonal bipyramid rearrangements around small ions and rotational polyhedral movements in simulating oxygen vacancy conduction in oxygen-deficient double perovskites. 相似文献
999.
1000.
Stability and Unimolecular Reactivity of Palladate(II) Complexes [LnPdR3]− (L=Phosphine,R=Organyl,n=0 and 1)
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Marlene Kolter Prof. Dr. Konrad Koszinowski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15744-15750
The reduction of PdII precatalysts to catalytically active Pd0 species is a key step in many palladium‐mediated cross‐coupling reactions. Besides phosphines, the stoichiometrically used organometallic reagents can afford this reduction, but do so in a poorly understood way. To elucidate the mechanism of this reaction, we have treated solutions of Pd(OAc)2 and a phosphine ligand L in tetrahydrofuran with RMgCl (R=Ph, Bn, Bu) as well as other organometallic reagents. Analysis of these model systems by electrospray‐ ionization mass spectrometry found palladate(II) complexes [LnPdR3]? (n=0 and 1), thus pointing to the occurrence of transmetallation reactions. Upon gas‐phase fragmentation, the [LnPdR3]? anions preferentially underwent a reductive elimination to yield Pd0 species. The sequence of the transmetallation and reductive elimination, thus, constitutes a feasible mechanism for the reduction of the Pd(OAc)2 precatalyst. Other species of interest observed include the PdIV complex [PdBn5]?, which did not fragment via a reductive elimination but lost BnH instead. 相似文献