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811.
812.
The beam quality factor for a coherently combined beam is studied in detail. A theoretical analysis and a numerical calculation are given to illustrate that the M2 factor is not a proper means for evaluating the beam quality of a coherently combined beam. The beam propagation factor is introduced to evaluate the beam quality. The effect of phase error on the beam quality is also studied. Results indicate that the beam quality of a coherently combined beam depends mainly on the fill factor of the laser array and not on the number of lasers. It is also revealed that the allowed phase error does not change with the number of lasers in order to ensure the energy encircled in a certain bucket. 相似文献
813.
Lei Shi Xiaolin Huang Zheng Tian Johan A. K. Suykens 《Advances in Computational Mathematics》2014,40(2):517-551
The quantile regression problem is considered by learning schemes based on ? 1—regularization and Gaussian kernels. The purpose of this paper is to present concentration estimates for the algorithms. Our analysis shows that the convergence behavior of ? 1—quantile regression with Gaussian kernels is almost the same as that of the RKHS-based learning schemes. Furthermore, the previous analysis for kernel-based quantile regression usually requires that the output sample values are uniformly bounded, which excludes the common case with Gaussian noise. Our error analysis presented in this paper can give satisfactory convergence rates even for unbounded sampling processes. Besides, numerical experiments are given which support the theoretical results. 相似文献
814.
815.
Algebras and Representation Theory - We provide a necessary and sufficient condition for a type D Temperley-Lieb algebra TLDn(δ) being semi-simple by studying branching rule for cell modules.... 相似文献
816.
Naphthalene‐Functionalized,Photoluminescent Room Temperature Ionic Liquids Bearing Small Counterions
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Hongxia Zhu Geping Zhang Mengjun Chen Shengju Zhou Guihua Li Xiaolin Wang Prof. Qingzeng Zhu Prof. Hongguang Li Prof. Jingcheng Hao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(18):6286-6293
Obtaining π‐conjugated room temperature ionic liquids (RTILs) is difficult because of the relatively strong π–π interaction among the π‐moieties. Existing strategies by using bulky counterions greatly hindered further property optimization and potential applications of these intriguing functional fluids through simple ion exchange. Herein, four naphthalene‐functionalized, π‐conjugated RTILs with small counterions (Br?) have been facilely synthesized with high yields. Our strategy is to attach branched alkyl chains to the cationic backbone of the target compounds ( 2 a – d ), which effectively tune inter‐ and intramolecular interactions. Compounds 2 a – d have satisfactory thermal stability (up to 300 °C) and low melting points (<?19 °C). Rheological measurements revealed the fluid character of 2 a – d , whose viscosity decrease with the increase of the alkyl chain length and temperature. The presence of the π‐conjugated naphthalene moiety imparts 2 a – d photoluminescent properties in bulk solutions. Moreover, the absence of strong π–π stacking among the naphthalene units in solvent‐free states enables them to be used as a new generation of photoluminescent inks. 相似文献
817.
We study the effects of demand uncertainty on optimal decisions and the expected profit of a price-setting newsvendor who faces either additive or multiplicative stochastic demand. Our key findings are as follows. (1) A stochastically larger demand may even lead to a smaller order size and a lower profit when price is endogenous. (2) A stochastically larger demand will lead to a higher selling price in general for the additive demand case but to a lower selling price under certain mild conditions for the multiplicative demand case. Moreover, if the larger demand can be represented by a transformation of the lower one, it will lead to a higher expected profit for both demand cases. However, except for the setting with a zero shortage cost, a larger demand may not necessarily result in a higher expected profit in general. (3) Under mild conditions, a less variable demand will lead to a higher and lower selling price for the additive and multiplicative demand case, respectively, and a higher expected profit for both cases. 相似文献
818.
Nonlinear Dynamics - This paper investigates distributed Nash equilibrium seeking problems for networked games played by multiple high-order systems with disturbance rejection and communication... 相似文献
819.
820.