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811.
基于偏微分方程的闪光照相图像修补算法   总被引:1,自引:1,他引:0       下载免费PDF全文
针对闪光照相底片图像可能含有缺陷的问题,提出了一种基于偏微分方程的闪光照相图像修补算法,该算法在曲率驱动扩散(CDD)方法的基础上,引入变系数的p-Laplace算子,并将其与BSCB方法交替进行修补。该算法能兼顾水平线的梯度方向和切线方向的修补信息,符合人眼的"连通性准则",并能有效修补面积较大的破损区域。与CDD修补算法相比,该算法能快速收敛,具有更好的修补效果。  相似文献   
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.
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.
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.
The effect of demand uncertainty in a price-setting newsvendor model   总被引:1,自引:0,他引:1  
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.
Ai  Xiaolin 《Nonlinear dynamics》2020,101(2):961-976
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   
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820.
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