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11.
In this article, we have proposed an image segmentation algorithm FABC, which is a kind of unsupervised classification (clustering), where we combine the concept of artificial bee colony optimization (ABC) and the popular fuzzy C means (FCM) and named it as fuzzy-based ABC or FABC. In FABC, we have used fuzzy membership function to search for optimum cluster centers using ABC. FABC is more efficient than other optimization techniques such as genetic algorithm (GA), particle swarm optimization (PSO) and expectation maximization (EM) algorithms. FABC overcomes the drawbacks of FCM as it does not depend on the choice of initial cluster centers and it performs better in terms of convergency, time complexity, robustness and segmentation accuracy. FABC becomes more efficient as it takes the advantage of the randomized characteristics of ABC for the initialization of the cluster centers. The experiments with FABC, GA, PSO and EM have been done over various grayscale images including some synthetic, medical and texture images, and segmentation of such images is very difficult due to the low contrast, noise and other imaging ambiguities. The efficiency of FABC is proven by both quantitative and qualitative measures. 相似文献
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A high efficiency Yb:YAG/YAG composite slab laser is presented, in which the corner-pumped scheme is adopted. The slab is a composite crystal of Yb:YAG bonded thermally with undoped YAG at both edges. The pump light from diode arrays is coupled into the slab through four chamfers at the four corners independently. The pump absorption efficiency is studied, and an analysis method has been developed as a guide to optimize the geometric parameters of the composite slab, to obtain higher pump absorption efficiency and uniformity. The influence of the internal thermal lens on the laser resonator is analyzed. A 1016 W continuous-wave output has been obtained with the slope efficiency and optical-to-optical efficiency of 42.8% and 34.4%, respectively. 相似文献
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本文通过过载保护装置的设计方法和步骤扼要阐述了“设计方法学”的基本观点与方法。并着重分析了任务提出、功能结构、物理效应、有效结构特征、评价选择、总体设计等基本步骤的实现以及寻找最佳方案的方法。 相似文献
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Dubis Eligiusz Poplawski Janusz Wróbel Jerzy T. Kúsmierz Józef Maliński Edmund Szafranek Janusz 《Lipids》1986,21(7):434-439
The exoskeleton triglyceride fraction isolated from the Colorado beetle,Leptinotarsa decemlineata Say, was studied. Analysis of the hydrolysis products and direct capillary column gas chromatography showed that, apart from
triglycerides, the fraction contained no diol lipids. The composition of the natural triacylglccerol mixture was assessed
by gas chromatography and by field desorption and electron impact mass spectrometry. Triglycerides isolated from the Colorado
beetle are typical glycerol triesters, with long chain (mainly oleic or palmitic) fatty acids. The structures of two major
components (91%), i.e., trioleoyl glycerol and 1,2-dioleoyl-3-palmitoyl glycerol, were determined. 相似文献
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Ass.-Prof. Dipl.-Ing. Dr. mont. Heinrich Mali Bernhard Spuida 《BHM Berg- und Hüttenm?nnische Monatshefte》2013,158(2):47-52
The mineralogical composition and structural properties of iron ores control their behaviour in industrial reduction plants. Micro-images of polished sections are processed by the software VisuMet to determine the proportions of limonite, hematite and magnetite. From the mineralogical composition and the structural properties of iron ores VisuMet assesses their reduction properties at standard reduction conditions. 相似文献
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本文给出了厚透镜实现分数阶付里变换的光学结构;定量分析了阊最透镜和双厚秀镜结构中分数付里叶变换和透镜参数之间的关系。计算表明用厚透镜可以实现分类阶付时变换。 相似文献