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11.
This study provides a stability theory for the nonlinear least-squares formulation of estimating the diffusion coefficient in a two-point boundary-value problem from an error-corrupted observation of the state variable. It is based on analysing the projection of the observation on the nonconvex attainable set.This research was started while G. Chavent visited the Technical University of Graz. Support through the Steiermaerkische Landesregierung is gratefully acknowledged. 相似文献
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C. Ziegler F. Baudenbacher H. Karl H. Kinder W. Göpel 《Fresenius' Journal of Analytical Chemistry》1991,341(3-4):308-313
Summary The influence of different preparation conditions and substrate surface orientations on the superconducting properties of thin YBa2Cu3O7–x (YBCO) films on silicon was studied. Comparative electrical and surface spectroscopic measurements were performed. SAM and SIMS depth profile analysis show an enrichment of barium at the interface between the superconductor and silicon for samples with Tc<76 K. Comparison with XPS data obtained for thin silicon films on YBCO indicates the formation of barium and yttrium silicates at the interface under these conditions. 相似文献
14.
Karl Sigman 《Operations Research Letters》2007,35(5):581-583
In Mandelbaum and Yechiali [The conditional residual service time in the M/G/1 queue, http://www.math.tau.ac.il/∼uriy/publications (No. 30a), 1979] and in Fakinos [The expected remaining service time in a single-server queue, Oper. Res. 30 (1982) 1014-1018] a simple formula is derived for the (stationary) expected remaining service time in a M/G/1 queue, conditional on the number of customers in the system. We give a short new proof of the formula using Rate Conservation Law, and generalize to handle higher moments. 相似文献
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Karl Strambach C. G. Bartolone 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》1989,59(1):93-99
This research was supported by M.P.I. (R.S. 40%). 相似文献
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Marko D. Mihovilovic Bernhard Müller Markus Spina Arjumand I. Durrani Peter Stanetty Georg Dazinger Karl Kirchner 《Monatshefte für Chemie / Chemical Monthly》2006,137(6):785-794
Summary. Recombinant Escherichia coli overexpressing Pseudomonas sp. NCIMB 9872 cyclopentanone monooxygenase (CPMO, EC 1.14.13.16) and Acinetobacter sp. NCIMB 9871 cyclohexanone monooxygenase (CHMO, EC 1.14.13.22) have been utilized in whole-cell Baeyer-Villiger biotransformations of prochiral bicycloketones. A significant difference in substrate acceptance and stereoselectivity was
observed for bicyclo[3.3.0] and bicyclo[4.3.0] substrates. A plausible mechanism of these transformations was established
by means of high level DFT/B3LYP calculations suggesting an essential difference in electronic requirements for a successful
enzymatic conversion, which was similarly encountered in recombinant whole-cell mediated biooxidations. Some of the lactones
produced in the biocatalytic Baeyer-Villiger oxidation represent key intermediates for the synthesis of indole alkaloids. 相似文献
20.
Karl F. Canter 《Hyperfine Interactions》1992,73(1-2):159-171
The present status of low energy positron diffraction (LEPD) and positron reemission microscopy (PRM) is reviewed in the context
of unanswered questions regarding the elastic scattering of positrons in the 1–300 eV energy range from atoms in solids and
at solid surfaces. Recent LEPD studies yield an agreement between theoretical and experimental diffraction intensities for
semiconductors that has never been equalled in electron diffraction studies. This situation is discussed in terms of the repulsive
interaction between the positron and the embedded atomic potential and the lack of exchange with the nonspherically distributed
valence electrons. The scattering of re-emitted positrons in PRM from atoms chemisorbed or physisorbed on the re-emitting
surface has not yet received the same theoretical attention as scattering from embedded atoms in LEPD. Possible ways in which
positron scattering from overlying atomic structures manifests itself in PRM as well as positron re-emission holography are
discussed, both from the practical viewpoint of observing these structures and in the context of fundamental questions regarding
the positron re-emission process itself. 相似文献