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排序方式: 共有345条查询结果,搜索用时 31 毫秒
1.
The Chinese Remainder Theorem (CRT) explains how to estimate an integer-valued number from the knowledge of the remainders obtained by dividing such unknown integer by co-prime integers. As an algebraic theorem, CRT is the basis for several techniques concerning data processing. For instance, considering a single-tone signal whose frequency value is above the sampling rate, the respective peak in the DFT informs the impinging frequency value modulo the sampling rate. CRT is nevertheless sensitive to errors in the remainders, and many efforts have been developed in order to improve its robustness. In this paper, we propose a technique to estimate real-valued numbers by means of CRT, employing for this goal a Kroenecker based M-Estimation (ME), specially suitable for CRT systems with low number of remainders. Since ME schemes are in general computationally expensive, we propose a mapping vector obtained via Kroenecker products which considerably reduces the computational complexity. Furthermore, our proposed technique enhances the probability of estimating an unknown number accurately even when the errors in the remainders surpass 1/4 of the greatest common divisor of all moduli. We also provide a version of the mapping vectors based on tensorial n-mode products, delivering in the end the same information of the original method. Our approach outperforms the state-of-the-art CRT methods not only in terms of percentage of successful estimations but also in terms of smaller average error.  相似文献   
2.
Visual evaluation experiments of color discrimination threshold and suprathreshold color‐difference comparison were carried out using CRT colors based on the psychophysical methods of interleaved staircase and constant stimuli, respectively. A large set of experimental data was generated ranged from threshold to large suprathreshold color difference at the five CIE color centers. The visual data were analyzed in detail for every observer at each visual scale to show the effect of color‐difference magnitude on the observer precision. The chromaticity ellipses from this study were compared with four previous published data, of CRT colors by Cui and Luo, and of surface colors by RIT‐DuPont, Cheung and Rigg, and Guan and Luo, to report the reproducibility of this kind of experiment using CRT colors and the variations between CRT and surface data, respectively. The present threshold data were also compared against the different suprathreshold data to show the effect of color‐difference scales. The visual results were further used to test the three advance color‐difference formulae, CMC, CIE94, and CIEDE2000, together with the basic CIELAB equation. In their original forms or with optimized KL values, the CIEDE2000 outperformed others, followed by CMC, and with the CIELAB and CIE94 the poorest for predicting the combined dataset of all color centers in the present study. © 2005 Wiley Periodicals, Inc. Col Res Appl, 30, 198–208, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20106  相似文献   
3.
荫罩的热变形使电子束产生着屏偏移 ,进而导致了色纯变坏。本文采用大型软件ANSYS对 1 5英寸荫罩进行了热变形的有限元仿真 ,从而得到了电子束的着屏偏移。建立了包括阴极射线管 (CRT)里所有部件的完整的有限元模型。荫罩被建为无孔连续薄壳的模型 ,对它的表面导热系数和表面弹性模量作了等效的计算。考虑了弹簧片的预应力以及弹簧片和销钉的连接。这样可使我们的分析模型更接近真实情况。本文给出了 50 0、1 0 0 0、1 0 0 0 0s时的热变形和电子束着屏偏移。分析表明 :电子束着屏偏移的最大值发生在 50 0s左右。利用这种分析方法及研究结果可指导新型荫罩的设计和研制。  相似文献   
4.
Aqueous photoresists that are capable of higher resolutions than are currently employed by the cathode ray tube (CRT) industry were developed by combining photoactivators, which activate at shorter UV wavelengths with polyvinylpyrrolidone (PVP). Two photoactivators were synthesized: 4,4′‐diazido‐2,2′‐biphenyl disodium disulfonate (DABP), which has a maximum absorbance at 264 nm, and 4,4′‐diazido‐2,2′‐biphenylethane disodium disulfonate (DABPE), which has a maximum absorbance at 258 nm. The PVP/DABP and PVP/DABPE photoresists successfully imaged a pattern with resolution as small as 4.4 μm with photoactivator concentrations greater than 20% of the PVP concentration. Addition of silane and emulgen greatly improved the performance of the photoresists with more uniform coatings of thicknesses of up to 1.4 μm. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1637–1644, 2006  相似文献   
5.
CRT显示器的颜色转换模型   总被引:3,自引:0,他引:3  
在分析CRT显示器色彩呈现原理的基础上,用色彩管理软件ProfileMaker 5.0以及Eye-One Pro分光光度仪对N700DF CRT显示器进行屏幕的校准和特性化;采用多项式回归算法建立了CIERGB到CIEXYZ颜色转换模型,并对转换模型所得到的X、Y、Z计算值与实际测量值进行了比较.在所抽取的12个色块中...  相似文献   
6.
戴元 《微型电脑应用》2011,27(11):14-15,68
提出了如何设计开发网络设备配置信息备份系统,实现各种网络设备配置信息的远程备份,并用VBScript语言进行了具体实现。  相似文献   
7.
In this paper the problem of the number of fixed points for an RSA algorithm is considered. This is an important question from the point of view of any cryptosystem. We have estimated the expected value of this number for randomly chosen RSA parameters. It turned out that it is O(ln2n), and the probability of finding such a point is O(ln2n/n). Thus, these values are really negligible, which had been intuitively expected.  相似文献   
8.
原有的RSA故障攻击针对的都是运行在智能卡等硬件上的算法,为研究针对RSA软件实现方式的故障攻击,剖析中国剩余定理软件实现算法,提出针对OpenSSL密码库的RSA算法软件实现的故障攻击算法,给出一种只需要一次错误签名的改进攻击方案。通过仿真实验验证算法的可行性,并给出抵御此类攻击的有效措施。  相似文献   
9.
Decision rules have been developed and applied to the bills of materials of a color cathode‐ray tube (CRT) and a liquid‐crystal‐display (LCD) desktop monitor to determine which product and process materials will be evaluated in an environmental life‐cycle assessment. Materials of significant mass, of technological importance, and of potential environmental impact are targeted. The list of materials identified are those for which life‐cycle inventory data will be obtained for the materials extraction and materials processing life‐cycle stages of a CRT and an LCD. Additionally, materials identified will also be used to represent life‐cycle impact in terms of resource consumption, as well as surrogates for occupational health impacts.  相似文献   
10.
用多隐层BP网实现的CRT色度变换   总被引:10,自引:0,他引:10       下载免费PDF全文
为了实现彩色信息的标准化显示,需要对CRT的色度空间进行标定,也就是CRT的R、G、B空间与CIE的标准色度空间的相互转换问题,人工神经网络近年来被广泛应用于多种颜色空间的变换过程中,在分析前人经验的基础上,提出了一种采脾四隐层BP网的CRT的R、G、B与CIE的X、Y、Z色度空间的变换方法,实验结果表明,该方法的收敛性和训练时间均优于前人采用2个或3个隐层的方案,而且通过对512个训练样本的实验  相似文献   
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