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91.
In this article, we study for the ‐realization of the vector‐valued Schrödinger operator . Using a noncommutative version of the Dore–Venni theorem due to Monniaux and Prüss, we prove that the ‐realization of , defined on the intersection of the natural domains of the differential and multiplication operators which form , generates a strongly continuous contraction semigroup on . We also study additional properties of the semigroup such as extension to L1, positivity, ultracontractivity and prove that the generator has compact resolvent. 相似文献
92.
Both residual Cesàro alpha-integrability (RCI( α)) and strongly residual Cesàro alpha-integrability (SRCI(α)) are two special kinds of extensions to uniform integrability, and both asymp-totically almost negative association (AANA) and asymptotically quadrant sub-independence (AQSI) are two special kinds of dependence structures. By relating the RCI(α) property as well as the SRCI(α) property with dependence condition AANA or AQSI, we formulate some tail-integrability conditions under which for appropriate α the RCI(α) property yields L1-convergence results and the SRCI(α) property yields strong laws of large numbers, which is the continuation of the corresponding literature. 相似文献
93.
Nadezhda S. Temnyakova Dmitry A. Vasilenko Mstislav I. Lavrov Dmitry S. Karlov Yuri K. Grishin Vladimir L. Zamoyski Vladimir V. Grigoriev Elena B. Averina Vladimir A. Palyulin 《Mendeleev Communications》2021,31(2):219-220
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94.
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96.
In this paper, a nonparametric method for reliability
of the stress-strength model is proposed when the dependent stress variable
and strength variable are subject to right censoring. The dependence between
variables is measured by the common Farlie-Gumbel-Morgenstern copula function
and Clayton copula function. Using the empirical process theory, consistency
and asymptotic normality of the proposed estimator is established in this
paper. The results of numerical simulation show that the proposed method
performs well in the case of finite sample. The method proposed in this paper
has a wide application prospect in practice. 相似文献
97.
The galvanic behavior of a hollow cathode discharge versus an external weak magnetic field is investigated. The application of this field leads to disordering of the self-aligned states, which is detected as a resonance in the discharge current, named the magneto-galvanic signal. A correlation magneto-galvanic signal–operating voltage-current point is established and attributed to Penning ionization. The contribution of the metastable Ne I 1 s5 to the magneto-galvanic resonance is also verified. 相似文献
98.
Ruifang Yang Nanjing Zhao Xue Xiao Shaohui Yu Jianguo Liu Wenqing Liu 《Journal of Chemometrics》2015,29(8):442-447
Sparse non‐negative matrix factorization on right side factor (SNMF/R) has better performance in feature extraction than non‐negative matrix factorization. In this work, SNMF/R was first used to separate the overlapped three‐dimensional fluorescence spectra of polycyclic aromatic hydrocarbons mixtures in pure water, lake water, and river water, respectively. It is found that the similarity coefficients between the acquired three‐dimensional spectra and the corresponding reference spectra with random initials are all above 0.80; the recognition rate of SNMF/R is higher than that of PARAFAC and non‐negative matrix factorization algorithms, especially in the case of lake water and river water samples. In addition, SNMF/R does not need any initialization scheme designing during spectra separation. These results demonstrate that SNMF/R is an appropriate algorithm to separate the overlapped fluorescence spectra of polycyclic aromatic hydrocarbons in aquatic environment accurately and effectively. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
99.
Qiufen Wang Ying Huang Yang Zhao Wei Zhang Yan Wang 《Surface and interface analysis : SIA》2013,45(8):1297-1303
Tin‐based oxide Li2SnO3 has been synthesized by a hydrothermal route as negative material for lithium‐ion batteries. The microstructure and electrochemical properties of the as‐synthesized materials were investigated by some characterizations means and electrochemical measurements. The as‐synthesized Li2SnO3 is a porous rod, which is composed of many uniform and regular nano‐flakes with a size of 50–60 nm. Li2SnO3 also displays an electrochemical performance with high capacity and good cycling stability (510.2 mAh g?1 after 50 cycles at a current density of 60 mA g?1 between 0.0 V and 2.0 V verusus Li/Li+). Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
100.
《Journal of Dispersion Science and Technology》2013,34(6):753-756
Mixed vesicles can be formed spontaneously from aqueous mixture of the double‐tailed anionic surfactant sodium bis(2‐ethylhexyl) sulfosuccinate (AOT) and the nonionic surfactant octylphenoxypolyethoxyethanol (Triton X‐100) under the inducement of salt, the formation mechanism of which should be attributed to the compression of salt on the electric bilayers of the head groups. The stability and the polydispersity of the vesicles are superior to single‐component AOT vesicles, which can be proved by the TEM image and visual observation. The vesicle region was presented in a pseudo‐ternary diagram of AOT/TX‐100/brine. The size of the vesicle was measured using dynamic light scattering. It is found that the vesicle size increases with the salinity but decreases with the content of TX‐100 in the mixture at the same salinity. Especially, the vesicle size is independent of the surfactant concentration at fixed salinity. 相似文献