共查询到20条相似文献,搜索用时 46 毫秒
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组合NNSC收缩技术和改进四阶PDE的MMW图像恢复 总被引:1,自引:0,他引:1
毫米波(MMW)图像含有大量未知噪声,仅用一种方法恢复的效果较差,因此结合非负稀疏编码(NNSC)收缩技术和改进四阶偏微分方程(PDE)模型的优点,提出了一种基于组合处理的MMW图像恢复方法.NNSC收缩法具有自适应消噪图像的特性,和数据的属性无关;而改进四阶PDE能够消除二阶PDE产生的阶梯效应,同时避免光滑区域不平整的现象,具有较好的图像恢复效果.分别采用模拟的和真实的MMW图像进行测试,并用相对信噪比(RSNR)进行评判,实验表明,与NNSC收缩、基于四阶的PDE模型以及小波收缩等方法相比,所提出的方法能够有效地用于MMW图像的恢复. 相似文献
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在被动毫米波的图像恢复中,L-R算法是一种简单而有效的非线性方法。但当噪声不可忽略时,L-R算法难以获得较好的复原结果。自适应稀疏表示,作为一种新的信号处理方法,具有表达信号灵活的特点,能够在保持目标特征的同时有效地去除噪声。该文提出一种基于自适应稀疏表示的L-R算法。首先采用稀疏信号表示的方法进行去噪,然后使用L-R算法进行图像恢复。这种改进算法通过使用基于自适应稀疏表示的去噪算法有效地减少了噪声对L-R算法的影响。实验数据的成像结果表明:该文的改进算法提高了L-R算法的性能,可用于低信噪比的图像复原。 相似文献
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图像盲复原( IBR)问题一直是图像处理中的重要研究课题。目前空间不变的多通道图像盲复原算法研究较为普遍,这种算法具有较好的盲去模糊效果,但是对噪声的抑制能力不足,特别是对含有大量噪声的低分辨率图像而言,消噪效果较差。基于K-奇异值分解( K-SVD )的模型能够有效地处理噪声方差较大的图像,但是不能自适应图像的稀疏先验性。为了解决上述问题,在全变分( TV)多通道IBR算法处理的基础上,结合一种改进的K-SVD消噪模型的优势,提出了一种新的组合图像恢复方法。改进的K-SVD模型考虑了图像特征系数的稀疏先验知识和最大化稀疏度,具有自适应的消噪鲁棒性。分别采用模拟的和真实的低分辨率图像(毫米波图像)进行测试,与采用单一的多通道盲恢复和图像消噪算法相比,实验结果表明所提出的图像恢复方法具有较好的视觉效果和较高的信噪比。 相似文献
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在毫米波的图像恢复中,L-R算法是一种简单而有效的非线性方法,但当噪声不可忽略时,L-R算法难以获得较好的复原结果。针对毫米波图像数据量少和图像分辨率低的特点,提出基于改进自蛇模型和L-R算法毫米波图像恢复方法,以局部方差构造自蛇模型的边缘停止函数,其改进自蛇模型在消除噪声的同时更能够保留图像中的边缘和细节特征,然后使用L-R算法进行图像恢复,这种改进算法通过使用基于改进自蛇模型去噪能有效地减少噪声对L-R算法的影响。实验结果表明:在信噪比和相关度方面本文算法提高了L-R算法的性能,可用于含噪声的图像复原。 相似文献
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为了克服傅立叶域和小波域正则化方法不能同时保持目标特征和有效滤除噪声的缺点,提出一种被动毫米波图像恢复的新方法。它利用稀疏表示表达信号灵活的特点,对逆滤波后的毫米波图像采用基于奇异值分解的K聚类(K-SVD)算法进行学习,自适应地得到图像恢复需要的基函数。与傅立叶域和小波域正则化方法相比,论文方法采用了自适应的处理方法,因此能够更好地保持目标特征,更有效地抑制噪声,进而更好地恢复图像。将论文方法用于被动毫米波仿真图像的恢复,得到了很好的结果。因此,它是一种有效的被动毫米波成像方法。 相似文献
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针对噪声在多小波分解后的尺度性以及图像本身的特性,提出了一种基于遗传算法的多小波自适应去噪算法,该方法能通过遗传算法自适应地寻求去噪后图像的最小均方误差.实验结果表明,该算法优于传统算法,不仅能有效滤除图像的噪声,而且能较好地保留图像的边缘信息,具有更加理想的去噪效果. 相似文献
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Meihua Shen Wilfred Pau Nicolas Gani Jianping Wen Shashank Deshmukh Thorsten Lill Jian Zhang Hanming Wu Guqing Xing 《半导体技术》2004,29(8)
This paper presents a brief overview of the Applied Centura(R)DPS(R)system,configured with silicon etch DPS Ⅱ chamber, with emphasis on discussing tuning capability for CD uniformity control. It also presents the studies of etch process chemistry and film integration impact for an overall successful gate patterning development. Discussions will focus on resolutions to key issues, such as CD uniformity, line-edge roughness, and multilayer film etching integration. 相似文献
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White organic light-emitting devices based on fac tris(2- phenylpyridine) iridium sensitized 5,6,11,12-tetraphenylnap -hthacene 总被引:1,自引:0,他引:1
We have fabricated the white organic light-emitting devices (WOLEDs) based on 4,4' -bis(2,2 -diphenyl vinyl)-1,1' - biphenyl (DPVBi) and phosphorescence sensitized 5,6,11,12,-tetraphenylnaphthacene (rubrene). The device structure is ITO/2T-NATA (20 nm)/NPBX (20 nm)/CBP: x%Ir(ppy)3:0.5% rubrene (8 nm)/NPBX (5 nm)/DPVBi (30 nm)/Alq(30 nm)/LiF(0.5 nm)/A1. In the devices, DPVBi acts as a blue light-emitting layer, the rubrene is sensitized by a phosphorescent material, fac tris (2-phenylpyridine) iridium [Ir(ppy)3], acts as a yellow light-emitting layer, and N,N' -bis- (1-naphthyl)- N,N' -diphenyl -1, 1' -biphenyl-4,4' -diamine (NPBX) acts as a hole transporting and exciton blocker layer, respectively. When the concentration of Ir (PPY)3 is 6wt%, the maximum luminance is 24960 cd/m^2 at an applied voltage of 15 V, and the maximum luminous efficiency is 5.17 cd/A at an applied voltage of 8 V. 相似文献
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Complete approach to automatic identification and subpixel center location for ellipse feature 总被引:1,自引:0,他引:1
XUE Ting WU Bin SUN Mei YE Sheng-hua 《光电子快报》2008,4(1):51-54
To meet the need of automatic image features extraction with high precision in visual inspection, a complete approach to automatic identification and sub-pixel center location for similar-ellipse feature is proposed. In the method, the feature area is identified automatically based on the edge attribute, and the sub-pixel center location is accomplished with the leastsquare algorithm. It shows that the method is valid, practical, and has high precision by experiment. Meanwhile this method can meet the need of instrumentation of visual inspection because of easy realization and without man-machine interaction. 相似文献
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Credence Systems Corporation 《半导体技术》2004,29(9)
Integrated circuits (ICs) intended for increasingly sophisticated automotive applications bring unique test demands. Advanced ICs for applications such as highly integrated automatic braking system (ABS) and airbag controllers combine high voltage digital channels, significant VI demands and precise timing capability. Along with continued missioncritical reliability concerns, the trend toward higher voltage operation and increased device integration requires specialized test capabilities able to extend across the wide operating ranges found in automotive applications. Among these capabilities, automotive test requirements increasingly dictate a need for a cost-effective versatile mixed-signal pin electronics with very high data rates reaching up to 50MHz with a voltage swing of-2 V to +28 V. 相似文献
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It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV). 相似文献
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Zhang Xinsheng 《中国通信》2014,(1)
正Happy New Year!As we step into a new year,we take a look back at the key feature topics covered in China Communications over the past 12 months and set out our expecta- 相似文献
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正For a long time,optical and wireless systems/net-works are developed in separate communities witha few attempts for in-depth convergence.In fact,it prom-ises many advantages to combine the optical and wire-less technologies in the levels of systems and networks.Recently,both academia and industry have made manyefforts to enter a new phase of development to take op-tical and wireless systems as fully integrated networks.To provide high bandwidth and reliable service for bothfixed and mobile users,a well-designed network must 相似文献
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