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Hybrid Fuzzy Classifiers
Published in Anil Kumar, Priyadarshi Upadhyay, A. Senthil Kumar, Fuzzy Machine Learning Algorithms for Remote Sensing Image Classification, 2020
Anil Kumar, Priyadarshi Upadhyay, A. Senthil Kumar
Bray Curtis is a statistical dissimilarity and named after J. Roger Bray and John T. Curtis. Apart from image processing, it is also used in biology and ecology. It is used to quantify the compositional dissimilarity between two different sites, based on counts at each site. Bray Curtis is a normalization method that is commonly used in botany, ecology, and environmental science fields. It visualizes the space as a grid just like city block distance. It is directly related to the Sorenson similarity index. One important property: if all the coordinates are positive, then the Bray Curtis value is between 0 and 1. For exactly similar coordinates, its value is 0. If either vectors overlap or have zero coordinates, then Bray Curtis dissimilarity cannot be defined (Bloom, 1981). The Bray Curtis dissimilarity does not satisfy the triangle inequality and hence it is not exactly a distance. Bray Curtis dissimilarity is given by Equation (5.18): () D(Xj,Vi)=∑Abs[Xj−Vi]∑Abs[Xj−Vi];(Bray CurtisIndex)
Diversity of microbial community structure and their association with phthalic acid esters and physicochemical parameters in informal landfills
Published in Environmental Technology, 2022
Qin Yin, Haihong Yan, Xiaoya Guo, Yu Liang, Xingzhi Wang, Yuegang Nian, Haiyan Wang
A Venn diagram was used to evaluate the unique and shared operational taxonomic units (OTUs) at different informal landfill depths. Based on the Bray–Curtis dissimilarity, the relationship between the samples was illustrated using nonmetric multidimensional scaling. Spearman’s correlation coefficients were determined using the R Vegan package and were calculated. Redundancy analysis (RDA) was performed to analyze the relationship between the bacterial community and physicochemical factors using the Canoco (V 4.5) software.