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351.
An adaptive digital image watermark algorithm with strong robustness based on gray-scale morphology is proposed in this paper. The embedded strategies include: The algorithm seeks and ex-tracts adaptively the image strong texture regions. The algorithm maps the image strong texture region to the wavelet tree structures, and embeds adaptively watermark into the wavelet coefficients corre-sponding to the image’s strong texture regions. According to the visual masking features, the algorithm adjusts adaptively the watermark-embedding intensity. Experimental results show the algorithm is robust to compression, filtering, noise as well as strong shear attacks. The algorithm is blind watermark scheme. The image strong texture region extraction method based on morphology in this algorithm is simple and effective and adaptive to various images. 相似文献
352.
在液晶电视机的型式试验中经常遇到产品不符合标准要求的问题,这些问题会对用户的人身安全造成侵害。针对液晶电视机安规认证中常见的发热、防触电结构、接触电流和拔出插头放电量试验、电气间隙和爬电距离以及防火等问题,文章对标准进行深入解读并探讨相应的解决方案。 相似文献
353.
Wen‐Yi Cai Liang‐Dong Feng Shan‐Hu Liu Jun‐Jie Zhu 《Advanced functional materials》2008,18(20):3127-3136
A Hemoglobin‐CdTe‐CaCO3@polyelectrolyte 3D architecture is synthesized by a stepwise layer‐by‐layer method and is further used to fabricate an electrochemistry biosensor. While the calcium carbonate (CaCO3) microsphere acts as an effective host for the loading of cadmium telluride (CdTe) quantum dots due to its channel‐like structure, the polyelectrolyte layers further increase the loading amount and help in the formation of a thick and uniform quantum‐dot “shell”, which not only improves the stability of the spheres in water, but also contributes to the fast and effective direct electron transfer between the protein redox center and the macroscopic electrode. The materials are characterized and compared, and the possible mechanism for the direct electrochemistry phenomenon is hypothesized. Our work not only provides a facile and effective route for the preparation of quantum‐dot‐loaded spheres, but also sets an example of how the structure of functional materials can be tuned and related to their applications. In addition, it is one of the few examples of using CaCO3 microspheres in quantum‐dot loading and biosensing. 相似文献
354.
355.
Lp(Rm × Rn) boundedness is considered for the multiple Marcinkiewicz integral. Some size conditions implying the Lp(Rm × Rn) boundedness of the multiple Marcinkiewicz integral for some fixed 1 > p > ∞ are obtained. 相似文献
356.
Two multivariate hazard rate stochastic orders are introduced and studied. Their meaning, properties, and relationship to other common stochastic orders are examined and investigated. Some examples that illustrate the theory are detailed. Finally, some applications of the new orders in reliability theory and in actuarial science are described. 相似文献
357.
The problem of generating a matrix A with specified eigen‐pair, where A is a symmetric and anti‐persymmetric matrix, is presented. An existence theorem is given and proved. A general expression of such a matrix is provided. We denote the set of such matrices by ??????En. The optimal approximation problem associated with ??????En is discussed, that is: to find the nearest matrix to a given matrix A* by A∈??????En. The existence and uniqueness of the optimal approximation problem is proved and the expression is provided for this nearest matrix. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
358.
H. Hu 《Journal of Global Optimization》2003,25(2):237-242
This paper studies the existence of a uniform global error bound when a convex inequality g 0, where g is a closed proper convex function, is perturbed. The perturbation neighborhoods are defined by small arbitrary perturbations of the epigraph of its conjugate function. Under certain conditions, it is shown that for sufficiently small arbitrary perturbations the perturbed system is solvable and there exists a uniform global error bound if and only if g satisfies the Slater condition and the solution set is bounded or its recession function satisfies the Slater condition. The results are used to derive lower bounds on the distance to ill-posedness. 相似文献
359.
胡迪鹤 《数学物理学报(B辑英文版)》2003,23(2)
The structure of any a.s. self-similar set K(w) generated by a class of random elements {gn,wσ} taking values in the space of contractive operators is given and the approximation of K(w) by the fixed points {Pn,wσ} of {gn,ow} is obtained. It is useful to generate the fractal in computer. 相似文献
360.
Guoen Hu 《Journal of Mathematical Analysis and Applications》2003,283(2):351-361
boundedness is considered for the commutator of higher-dimensional Marcinkiewicz integral. Some conditions implying the and the boundedness for the commutator of the Marcinkiewicz integral are obtained. 相似文献