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Abstract: An adaptive support vector machine decision feedback equalizer (ASVM DFE) with less computational intensity based on least square support vector machine (LS SVM) is proposed in this paper. It solves linear systems iteratively. Simulations made in nonlinear time variant channels show that ASVM DFE performs excellent nonlinear equalization which is better than traditional decision feedback equalizer (DFE). [Copyright &y& Elsevier]

• The structure of reaction rim formed in ACR can block the migration of alkali ions. • The thickening of the reaction rim will inhibit the dedolomitization progress. • Large particles of dolostone will not react completely when exposed to NaOH solution. • The process of dedolomitization is shown in this manuscript. Alkali-carbonate reaction (ACR) are chemical reactions in concrete which may induce significant damage in concrete structures. Researchers have mainly focused on studies of the symptoms pertaining to the reaction, namely expansion and loss of mechanical properties. Not enough attention has been paid to the processes of dedolomitization in dolomitic rocks, such as migration of alkali and hydroxide ions to the surfaces of dolomite crystals, formation of products and effect of products on further migration of alkali and hydroxide ions to newly generated surface of the reacted dolomite crystals. These processes may significantly affect dedolomitization of dolomite and the resulted expansion of ACR. This paper investigates the alkali ion migration in dolostone and the process of dedolomitization of dolomite in the aggregates. Dolostones were crushed, sieved, and graded. Chemical, physical, and microstructural analysis of dolostones and degree of dedolomitization based on X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), atomic force microscopy (AFM), and laser scanning confocal microscopy (LSCM) of dolostones. Three of the key outcomes of this study provide new insights on the dedolomitization under autoclave conditions: (i) the degree of dedolomitization for large dolostone particles will stop increasing after a period of autoclaving time in 1 mol/L NaOH solutions, (ii) the reaction rim forms a nanofiltration-like structure that, when thick enough, can block the migration of alkali ions and inhibits the dedolomitization process, and (iii) the mechanism of dedolomitization of dolomite is that Mg2+ ions in the dolomite gradually dissolved from dolomite to form brucite with OH− ions, while the rest of dolomite eventually converts to calcite when all Mg2+ is dissolved. [ABSTRACT FROM AUTHOR]