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The fuzzy c-partition entropy has been widely adopted as a global optimization technique for finding the optimized thresholds for multilevel image segmentation. However, it involves expensive computation as the number of thresholds increases and often yields noisy segmentation results since spatial coherence is not enforced. In this paper, an iterative calculation scheme is presented for reducing redundant computations in entropy evaluation. The efficiency of threshold selection is further improved through utilizing the artificial bee colony algorithm as the optimization technique. Finally, instead of performing thresholding for each pixel independently, the presented algorithm oversegments the input image into small regions and uses the probabilities of fuzzy events to define the costs of different label assignments for each region. The final segmentation results is computed using graph cut, which produces smooth segmentation results. The experimental results demonstrate the presented iterative calculation scheme can greatly reduce the running time and keep it stable as the number of required thresholds increases. Quantitative evaluations over 20 classic images also show that the presented algorithm outperforms existing multilevel segmentation approaches. 相似文献
164.
烟气脱硫技术在浮法玻璃线上的应用 总被引:1,自引:1,他引:1
简介了烟气脱硫技术在浮法玻璃线上的应用情况,以工程实例详细介绍该技术在某浮法玻璃线上的设计、实施、应用情况以及重点、难点问题的处理,为该技术在浮法玻璃线的应用提供借鉴和参考. 相似文献
165.
Maoguo Gong Meng Jia Linzhi Su Shuang Wang Licheng Jiao 《International journal of remote sensing》2014,35(11-12):4009-4030
The Yellow River Estuary area of China is under great pressure from both human intervention and natural processes. For analysis of the changes in this area, this article presents a novel change-detection method based on a local fit-search model and kernel-induced graph cuts in multitemporal synthetic aperture radar images. Change detection involves assigning a label to every pixel. This task is naturally formulated in terms of energy minimization, which can be effectively solved by graph cuts. The difference image is transformed implicitly by a kernel function so that an alternative to complex modelling of the original data makes the piecewise constant model become applicable for graph cuts formulation. An issue is that graph cuts are sensitive to the initial estimate. The local fit-search model is proposed to approximate to the local histogram while selecting an optimal threshold for the initial labelling, which leads to an effective constraint for graph cuts and computational benefits as well. Visual and quantitative analyses obtained on the Yellow River Estuary data set confirm the effectiveness of the proposed method and that it outperforms the other state-of-the-art methods of change detection. 相似文献
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介绍了目前国内飞机蒙皮涂料的发展及存在的问题 ,分析讨论了性能优异的氟碳涂料在飞机蒙皮中应用的意义。 相似文献
169.
本文论述了目前国内外连续移动床炼焦新技术的工艺原理,介绍了国外连续移动床炼焦新技术的工艺流程及特性,并对连续移动床炼焦新技术的经济技术指标和焦炭特性进行了评述。 相似文献
170.
Sharks are the most dangerous predators of people in the sea, resulting in people being mauled and killed each year. A shark
repellent could help to diminish this danger. The aglycone of the shark repellent pavoninin-5, (25R)-cholest-5-en-3β,15α,26-triol (5a), was synthesized from diosgenin (9). Removing mercury from the Clemmensen reduction of 9 gave a higher yield of (25R)-cholest-5-en-3β,16β,26-triol, 10a, and was also more environmentally friendly. Attempted methods for the transposition of the C-16β hydroxyl to the 15α position
are described. A successful method for this transposition via the 15α-hydroxy-16-ketone, 8a, using the Barton deoxygenation reaction on the 16-alcohol 14b, is reported. 相似文献