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51.
车号定位识别与可信度估计 总被引:2,自引:0,他引:2
以车号的定位与识别为例,应用行投影法对车号图片进行倾斜行定位,证明了模拟与场景的二维互相关系数近拟等于一维投影互相关系数,在此基础上提列投影法快速行扫描识别算法及相应的可信度估计方法,这种方法对于室外拍摄的有复杂背景,光照变化,字体微倾,字符排列疏密不均及噪声干扰的车牌图像具有很好的识别效果。 相似文献
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天馈线电压驻波比是微波电路运行的重要指标,通过典型事例来阐述天馈线电压驻波比的劣化对微波电路的影响,并根据多年实践经验提出天馈线维护需注意的事项。 相似文献
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57.
卢金生 《理化检验(物理分册)》1995,31(6):27-30
通过对“软-软”、“中-软”、“中-中”、“中-硬”四组不同硬度匹配的滚子接触疲劳试验得出四条P-N曲线。并发现中硬度材料的接触疲劳寿命高于软材料,而当主试样为中硬时,与之相匹配的陪试件硬度越高,主试样的寿命越短,通过分析讨论解释了产生上述现象的原因及其失效机理。 相似文献
58.
This work discusses the issue of approximation in point set matching. In general, one may have two classes of approximations when tackling a matching problem: (1) an algorithmic approximation which consists in using suboptimal procedures to infer the assignment, and (2), a representational approximation which involves a simplified and suboptimal model for the original data. Matching techniques have typically relied on the first approach by retaining the complete model and using suboptimal techniques to solve it. In this paper, we show how a technique based on using exact inference in simple Graphical Models, an instance of the second class, can significantly outperform instances of techniques from the first class. We experimentally compare this method with well-known Spectral and Relaxation methods, which are exemplars of the first class. We have performed experiments with synthetic and real-world data sets which reveal significant performance improvement in a wide operating range. 相似文献
59.
The simultaneous contrast effect is investigated in this article. A total of 174 and 154 test/induction combinations were studied for CRT and surface colours respectively. Each combination was assessed by nine observers using a matching technique. The test and induction colours used for CRT colours were similar to surface colours using fabric samples. The results indicated a strong lightness contrast effect for both CRT and surface media; that is, the lightness of a test colour surrounded by a lighter induction colour was reduced for both CRT and surface colours. However, the effect in CRT medium was more pronounced than in the surface medium. © 2004 Wiley Periodicals, Inc. Col Res Appl, 30, 13–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20074 相似文献
60.
Motion picture films are susceptible to local degradations such as dust spots. Other deteriorations are global such as intensity
and spatial jitter. It is obvious that motion needs to be compensated for before the detection/correction of such local and
dynamic defects. Therefore, we propose a hierarchical motion estimation method ideally suited for high resolution film sequences.
This recursive block-based motion estimator relies on an adaptive search strategy and Radon projections to improve processing
speed. The localization of dust particles then becomes straightforward. Thus, it is achieved by simple inter-frame differences
between the current image and motion compensated successive and preceding frames. However, the detection of spatial and intensity
jitter requires a specific process taking advantage of the high temporal correlation in the image sequence. In this paper,
we present our motion compensation-based algorithms for removing dust spots, spatial and intensity jitter in degraded motion
pictures. Experimental results are presented showing the usefulness of our motion estimator for film restoration at reasonable
computational costs.
Received: 9 July 2000 / Accepted: 13 January 2002
Correspondence to:S. Boukir 相似文献