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41.
We study the multiple-sets split feasibility problem that requires to find a point closest to a family of closed convex sets in one space such that its image under a linear transformation will be closest to another family of closed convex sets in the image space. By casting the problem into an equivalent problem in a suitable product space we are able to present a simultaneous subgradients projections algorithm that generates convergent sequences of iterates in the feasible case. We further derive and analyze a perturbed projection method for the multiple-sets split feasibility problem and, additionally, furnish alternative proofs to two known results. 相似文献
42.
Measuring the one-particle excitations of ultracold fermionic atoms by stimulated Raman spectroscopy
We propose a Raman spectroscopy technique which is able to probe the one-particle Green function, the Fermi surface, and the quasiparticles of a gas of strongly interacting ultracold atoms. We give quantitative examples of experimentally accessible spectra. The efficiency of the method is validated by means of simulated images for the case of a usual Fermi liquid as well as for more exotic states: specific signatures of, e.g., a d-wave pseudogap are clearly visible. 相似文献
43.
Influence of Solution Volume on the Dissolution Rate of Silicon Dioxide in Hydrofluoric Acid 下载免费PDF全文
Boris Shvartsev Danny Gelman Ilia Komissarov Alon Epshtein Dr. David Starosvetsky Prof. Yair Ein‐Eli 《Chemphyschem》2015,16(2):370-376
Experimental data and modeling of the dissolution of various Si/SiO2 thermal coatings in different volumes of hydrofluoric acid (HF) are reported. The rates of SiO2‐film dissolution, measured by means of various electrochemical techniques, and alteration in HF activity depend on the thickness of the film coating. Despite the small volumes (0.6–1.2 mL) of the HF solution, an effect of SiO2‐coating thickness on the dissolution rate was detected. To explain alterations detected in HF activity after SiO2 dissolution, spectroscopic analyses (NMR and FTIR) of the chemical composition of the solutions were conducted. This is associated with a modification in the chemical composition of the HF solution, which results in either the formation of an oxidized species in solution or the precipitation of dissolution products. HF2? accumulation in the HF solution, owing to SiO2 dissolution was identified as the source of the chemical alteration. 相似文献
44.
“Buzzwords” are new words (i.e., neologisms) that enter the language and acquire great popularity as “fashion words.” To date, the dynamic aspect of buzzwords has not been the subject of a rigorous scientific analysis. In this study, we analyzed the appearance of buzzwords in the blogosphere and compared their dynamics to the one of nonpopular neologisms and well‐established words. It was found that the growth rate of buzzwords is exponential and higher than that of the blogosphere. Moreover, we have identified general early warning signals for an approaching tipping point in the dynamics of buzzwords indicating that as fashion words they are on their way to a tipping‐point of decline. The article presents these findings and others and concludes by presenting a model for studying the dynamics of new words entering the language. © 2010 Wiley Periodicals, Inc. Complexity 16: 58‐68, 2011 相似文献
45.
Bigeon Jean Le Digabel Sébastien Salomon Ludovic 《Computational Optimization and Applications》2021,79(2):301-338
Computational Optimization and Applications - The context of this research is multiobjective optimization where conflicting objectives are present. In this work, these objectives are only available... 相似文献
46.
Ohne Zusammenfassung 相似文献
47.
Ohne Zusammenfassung 相似文献
48.
49.
Goumri-Said S. Salomon L. Dufour J. P. De Fornel F. 《Optical and Quantum Electronics》2004,36(9):787-806
Numerical simulation of a two-dimensional probe–object system for photon scanning tunneling microscope is presented. The R-matrix propagation algorithm incorporated into the Fourier modal method was used to achieve an extended capability for modeling of a realistic system consisting of both a probe and a sample. The type of the mode guided through the dielectric probe and the coupling of the near-field to fundamental guiding mode in the probe are discussed. The influence of the probe parameters on the near-field images is investigated. Three different probe shapes were simulated in the constant height scanning mode. The transmitted flux intensity through the probe was found to be strongly dependent on the tip shape. The analysis shows a good agreement of the obtained results with the available theoretical works and confirming experimental results. The proposed numerical scheme can find applications for near-field probe characterization and provides an understanding of the degree of perturbation introduced by a probe tip in the experiment. 相似文献
50.
Yair Caro 《Journal of Graph Theory》1992,16(3):257-266
We introduce several variations of the Turan and Ramsey numbers, including zero-sum and bounded-average Ramsey numbers. Some interesting relations between these concepts are presented. In particular, a generalization of the k-local Ramsey numbers is established. 相似文献