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111.
孙博文 《数字社区&智能家居》2011,(20)
女性网站是针对女性群体的资讯门户,主要为女性提供前沿服饰、瘦身、休闲、娱乐、健康等生活咨询,体现现代都市女性热爱生活、展现自我的自信一面。文章旨在通过对典型女性网站网页设计的分析、解读各种页面元素,为女性网站的网页设计提供理论上的建议。 相似文献
112.
T. Hoang Ngan Le Chia-Chen Lin Chin-Chen Chang Hoai Bac LeAuthor vitae 《Digital Signal Processing》2011,21(6):734-745
Many secret sharing schemes for digital images have been developed in recent decades. Traditional schemes typically must deal with the problem of computational complexity, and other visual secret sharing schemes come with a higher transmission cost and storage cost; that is, each shadow size is m times as big as the original secret image. The new (2,n) secret sharing scheme for grayscale images proposed in this paper is based a combination of acceptable image quality using block truncation coding (BTC), high compression ratio discrete wavelet transform (DWT) and good subjective performance of the vector quantization (VQ) technique. Experimental results confirm that our proposed scheme not only generates a high quality reconstructed original image but also generates small, random-like grayscale shadows. 相似文献
113.
114.
Takeshi Emura 《Computational statistics & data analysis》2010,54(12):3033-3043
A goodness-of-fit testing procedure for Archimedean copula (AC) models is developed based on right-censored data. The proposed approach extends an existing method, which is suitable for the Clayton model, to general AC models. Asymptotic properties of the proposed test statistics under the true model assumption are derived. Simulation analysis shows that the proposed test has reasonable performance. Finally, two real data examples are analyzed for illustrative purposes. 相似文献
115.
Marco Riani 《Computational statistics & data analysis》2010,54(12):3300-3312
The forward search provides data-driven flexible trimming of a Cp statistic for the choice of regression models that reveals the effect of outliers on model selection. An informed robust model choice follows. Even in small samples, the statistic has a null distribution indistinguishable from an F distribution. Limits on acceptable values of the Cp statistic follow. Two examples of widely differing size are discussed. A powerful graphical tool is the generalized candlestick plot, which summarizes the information on all forward searches and on the choice of models. A comparison is made with the use of M-estimation in robust model choice. 相似文献
116.
Blanchet-Sadri et al. have shown that Avoidability, or the problem of deciding the avoidability of a finite set of partial words over an alphabet of size k≥2, is NP-hard [F. Blanchet-Sadri, R. Jungers, J. Palumbo, Testing avoidability on sets of partial words is hard, Theoret. Comput. Sci. 410 (2009) 968-972]. Building on their work, we analyze in this paper the complexity of natural variations on the problem. While some of them are NP-hard, others are shown to be efficiently decidable. Using some combinatorial properties of de Bruijn graphs, we establish a correspondence between lengths of cycles in such graphs and periods of avoiding words, resulting in a tight bound for periods of avoiding words. We also prove that Avoidability can be solved in polynomial space, and reduces in polynomial time to the problem of deciding the avoidability of a finite set of partial words of equal length over the binary alphabet. We give a polynomial bound on the period of an infinite avoiding word, in the case of sets of full words, in terms of two parameters: the length and the number of words in the set. We give a polynomial space algorithm to decide if a finite set of partial words is avoided by a non-ultimately periodic infinite word. The same algorithm also decides if the number of words of length n avoiding a given finite set of partial words grows polynomially or exponentially with n. 相似文献
117.
E. Popescu 《Journal of Computer Assisted Learning》2010,26(4):243-257
Personalized instruction is seen as a desideratum of today's e‐learning systems. The focus of this paper is on those platforms that use learning styles as personalization criterion called learning style‐based adaptive educational systems. The paper presents an innovative approach based on an integrative set of learning preferences that alleviates some of the limitations of similar systems. The adaptive methods used as well as their implementation in a dedicated system (WELSA) are presented, together with a thorough evaluation of the approach. The results of the experimental study involving 64 undergraduate students show that accommodating learning styles in WELSA has a beneficial effect on the learning process. 相似文献
118.
An obnoxious facility is to be located inside a polygonal region of the plane, maximizing the sum of the k smallest weighted Euclidean distances to n given points, each protected by some polygonal forbidden region. For the unweighted case and k fixed an O(n2logn) time algorithm is presented. For the weighted case a thorough study of the relevant structure of the multiplicatively weighted order-k-Voronoi diagram leads to the design of an O(kn3+n3logn) time algorithm for finding an optimal solution to the anti-t-centrum problem for every t=1,…,k, simultaneously. 相似文献
119.
120.
虎纹样文化是中华民族文化的重要组成部分,是民间审美的重要对象之一。山东民间虎纹样是山东地域内一种独特的文化现象,体现了当地的民风民俗、生存状态,有一定的文化价值、艺术价值、科技价值以及经济价值。本文从虎纹样的文化内涵、体现载体及艺术风格等方面对山东民间虎纹样文化进行了具体的阐述。这不但是对虎文化资料的丰富,同时唤起人们对虎纹样文化遗产的珍视,进而弘扬、保护。 相似文献