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71.
An adaptive color similarity function suitable for image segmentation and its numerical evaluation 下载免费PDF全文
Rodolfo Alvarado‐Cervantes Edgardo M. Felipe‐Riverón Vladislav Khartchenko Oleksiy Pogrebnyak 《Color research and application》2017,42(2):156-172
In this article, we present an adaptive color similarity function defined in a modified hue‐saturation‐intensity color space, which can be used directly as a metric to obtain pixel‐wise segmentation of color images among other applications. The color information of every pixel is integrated as a unit by an adaptive similarity function thus avoiding color information scattering. As a direct application we present an efficient interactive, supervised color segmentation method with linear complexity respect to the number of pixels of the input image. The process has three steps: (1) Manual selection of few pixels in a sample of the color to be segmented. (2) Automatic generation of the so called color similarity image (CSI), which is a gray level image with all the gray level tonalities associated with the selected color. (3) Automatic threshold of the CSI to obtain the final segmentation. The proposed technique is direct, simple and computationally inexpensive. The evaluation of the efficiency of the color segmentation method is presented showing good performance in all cases of study. A comparative study is made between the behavior of the proposed method and two comparable segmentation techniques in color images using (1) the Euclidean metric of the a* and b* color channels rejecting L* and (2) a probabilistic approach on a* and b* in the CIE L*a*b* color space. Our testing system can be used either to explore the behavior of a similarity function (or metric) in different color spaces or to explore different metrics (or similarity functions) in the same color space. It was obtained from the results that the color parameters a* and b* are not independent of the luminance parameter L* as one might initially assume in the CIE L*a*b* color space. We show that our solution improves the quality of the proposed color segmentation technique and its quick result is significant with respect to other solutions found in the literature. The method also gives a good performance in low chromaticity, gray level and low contrast images. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 156–172, 2017 相似文献
73.
The Pythagorean fuzzy set (PFS) is characterized by two functions expressing the degree of membership and the degree of nonmembership, which square sum of them is equal or less than 1. It was proposed as a generalization of a fuzzy set to deal with indeterminate and inconsistent information. In this study, we shall present some novel Dice similarity measures of PFSs and the generalized Dice similarity measures of PFSs and indicates that the Dice similarity measures and asymmetric measures (projection measures) are the special cases of the generalized Dice similarity measures in some parameter values. Then, we propose the generalized Dice similarity measures-based multiple attribute group decision-making models with Pythagorean fuzzy information. Then, we apply the generalized Dice similarity measures between PFSs to multiple attribute group decision making. Finally, an illustrative example is given to demonstrate the efficiency of the similarity measures for selecting the desirable ERP system. 相似文献
74.
An effective practical approach that allows not only a significant reduction in the scope of practical experiments in the course of studying suspension separation processes in hydrocyclones, but also makes it possible to assess the intensity of random components of the processes and define the interrelation between such components and hydrodynamics of flows in a hydrocyclone is presented. Within the frames of the developed probabilistic‐statistical model of suspension separation in hydrocyclones on the basis of statistical self‐similarity properties, a relationship was found between determined and random components of the processes. This allowed transitioning from three‐parameter probability density functions for suspension particles in hydrocyclones to two‐parameter functions; thus significantly improving the efficiency of practical application of the developed model. 相似文献
75.
对于新型反应堆的研究设计,零功率堆实验是不可缺少的阶段。为评估零功率堆和目标堆型间物理特性的相似程度,根据敏感性和不确定性分析技术,引入了3种评估系统间物理相似特性的指标。基于MONK连续能量下敏感性计算结果,编制了与其耦合的相似性分析程序,将分析程序的计算结果与TSUNAMI进行比较,结果显示符合良好。对两个主要相似性指标Ck和E大于0.95、大于0.9、大于0.8 3种情况进行了分析,结果显示,系统间的相似性指标大于0.9才能保证足够的相似性。以铅铋快堆为目标堆型,采用相似性分析方法对其进行了零功率堆物理方案的设计。 相似文献
76.
In the real world all events are connected. There is a hidden network of dependencies that governs behavior of natural processes. Without much argument it can be said that, of all the known data-structures, graphs are naturally suitable to model such information. But to learn to use graph data structure is a tedious job as most operations on graphs are computationally expensive, so exploring fast machine learning techniques for graph data has been an active area of research and a family of algorithms called kernel based approaches has been famous among researchers of the machine learning domain. With the help of support vector machines, kernel based methods work very well for learning with Gaussian processes. In this survey we will explore various kernels that operate on graph representations. Starting from the basics of kernel based learning we will travel through the history of graph kernels from its first appearance to discussion of current state of the art techniques in practice. 相似文献
77.
扩散过程是主导氡在铀矿岩中运移与析出的主要方式。铀矿原岩辐射较大且取样困难,不利于开展有关室内实验。为了解决以上问题,依据相似理论,以某花岗岩为原型,选取石英砂、铀尾砂、水泥、精铁粉和微硅粉等为原材料,制备了3种不同材料配比的圆柱形类铀矿岩试样,并测定了原型和试样的物理力学参数;然后采用密闭腔体法测量了原型和试样在不同包裹方式下的累积氡浓度,推导氡的扩散性能参数的计算公式,通过计算获得了原型和试样的氡扩散长度和扩散系数。实验结果表明:花岗岩原型与所制备的类铀矿岩的颗粒密度、抗压强度、抗拉强度、内聚力和内摩擦角相似比的均值分别为1.09∶1、3.93∶1、4.28∶1、3.47∶1和1.00∶1;花岗岩原型的扩散系数为0.146×10-6m2·s-1,类铀矿岩的扩散系数介于0.114×10-6~0.594×10-6m2·s-1之间,两者的相似比介于0.25∶1~1.28∶1之间。研究认为所制备的试样3在一定程度上可用来模拟花岗岩型铀矿岩,以满足室内实验的需求。 相似文献
78.
Abstract A simple method of similarity transformation is formulated to analyze a two‐dimensional creeping corner flow. By this peculiar transformation, governing equations for the plane velocity are reduced to a pair of ordinary differential equations. With a particular selection of appropriate boundary conditions, the field variables of velocity, pressure, vorticity, and stream function are obtained analytically. A special case with constant velocity at one boundary is explored. The salient characteristics of this example are used to compare with previous investigations. The present study shows that both approaches provide exactly the same solutions. A very interesting feature is that the velocity components in the coordinate system are independent of the radial direction. 相似文献
79.
Similarity measurement (SM) between pairs of features plays an essential role in the tooling retrieval. However, the number of tooling is usually large and difficult to retrieve. What’s more, the most similar tooling model is not always optimal in the case-based reasoning (CBR). To refine this situation, we propose a novel module-based similarity measurement method. Through dividing each tooling model into different modules, a new similarity is obtained by integrating all the most similar modules (MSMs) from existing tooling models. As a result, the new similarity is superior or at least equal to the result which is derived from previous methods. With the proposed method in this paper, feature similarities of modules between a new tooling ontology and each similar tooling ontology are calculated by fuzzy similarity measurement, and the MSMs are restructured to form a new tooling model after conflict resolution. A case study on forming mould is provided to illustrate the applications and prove the higher similarity by comparing with CBR. The proposed method has been adopted in an aircraft manufacturing company. 相似文献
80.
A. Yu. Polyakov S. M. Furmanov T. I. Bendik A. M. Kurlenkov 《Welding International》2017,31(11):868-873
A highly efficient energy-saving method of resistance projection welding of 3–4 components in a single cycle is described. The method is based on the automatically regulated gradual introduction of electric energy into the zone between the electrodes. 相似文献