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A Granular Computing Approach to Symbolic Value Partitioning

Wen L.-Y., Min F.

Fundamenta Informaticae

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2015

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Vol. 142, nr 1-4

337--371

EN

Symbolic value partitioning is a knowledge reduction technique in the field of data mining. In this paper, we propose a granular computing approach for the partitioning task that includes granule construction and granule selection algorithms. The granule construction algorithm takes advantage of local information associated with each attribute. A binary attribute value taxonomy tree is built to merge these attribute values in a bottom-up manner using information-loss heuristics. The use of a balancing technique enables us to control different nodes in the same level to have approximately the same size. The granule selection algorithm uses global information about all of the attributes in the decision system. Hence, nodes across the taxonomy forest of all attributes are selected and expanded using information-gain heuristics. We present a series of experimental results that demonstrate the effectiveness of the proposed approach in terms of reducing the data size and improving the resulting classification accuracy.

2

Rough Set Characterization for 2-circuit Matroid

Wang S., Zhu Q., Zhu W., Min F.

Fundamenta Informaticae

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2014

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Vol. 129, nr 4

377--393

EN

Rough sets are efficient to extract rules from information systems. Matroids generalize the linear independency in vector spaces and the cycle in graphs. Specifically, matroids provide well-established platforms for greedy algorithms, while most existing algorithms for many rough set problems including attribute reduction are greedy ones. Therefore, the combination between rough sets and matroids may bring new efficient solutions to those important and difficult problems. In this paper, 2-circuit matroids, abstracted from matroidal characteristics of rough sets, are studied and axiomatized. A matroid is induced by an equivalence relation, and its characteristics including the independent set and duality are represented with rough sets. Based on these rough set representations, this special type of matroid is defined as 2-circuit matroids. Conversely, an equivalence relation is induced by a matroid, and its relationship with the above induction is further investigated. Finally, a number of axioms of the 2-circuit matroid are obtained through rough sets. These interesting and diverse axioms demonstrate the potential for the connection between rough sets and matroids.

3

Hydration layers on clay mineral surfaces in aqueous solutions: a review

Min F., Peng C., Song S.

Archives of Mining Sciences

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2014

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Vol. 59, no. 2

489--500

EN

Hydration layer on clay mineral surfaces is originated from the adsorption of polar water molecules and hydrated cations on the surfaces through unsaturated ionic bonds, hydrogen bonds and van der Waals bonds. It has attracted great attentions because of their important influences on the dispersive stability of the particles in aqueous solutions. This review highlighted the molecular structure of clay minerals, the origin of hydration layers on clay mineral surfaces, the hydration layer structural model, hydration force and the main parameters of affecting the hydration layers on clay minerals (crystal structure, cationic type and strength, and solution pH). Also, the research methods for hydration layers were briefly described, especially the determination of hydration layer thickness by the Einstein viscosity method and AFM method. In addition, the applications of the stability of fine clay mineral particles in aqueous suspensions were summarized.

PL

Warstwa uwodniona na powierzchni minerałów ilastych (gliniastych) powstaje w wyniku adsorpcji polarnych cząsteczek wody i uwodnionych kationów powierzchniowych wiązanych za pomocą nienasyconych wiązań jonowych, wiązań wodorowych i wiązań van der Waalsa. Zagadnienie to wzbudza wiele uwagi ze względu na to, że w dużej mierze warunkuje stabilność dyspersyjną cząstek w roztworach wodnych. W pracy omówiono strukturę molekularną minerałów ilastych, powstawanie warstw uwodnionych na powierzchni minerałów ilastych i siły hydratacji; przedstawiono także model strukturalny warstwy uwodnionej oraz główne parametry warunkujące powstawanie warstwy uwodnionej na powierzchni materiałów ilastych (struktura krystaliczna, rodzaj występujących kationów, stężenie roztworu i jego pH). Ponadto, pokrótce przedstawiono metody badań, ze szczególnym uwzględnieniem badania grubości warstw uwodnionych przy zastosowaniu modelu lepkości Einsteina oraz metody AFM. Ponadto, zestawiono zagadnienia związane ze stabilnością cząstek drobnoziarnistych minerałowa ilastych i ich potencjalne zastosowania.

4

Experimental study on electrokinetic of kaolinite particles in aqueous suspensions

Min F., Zhao Q., Liu L.

Physicochemical Problems of Mineral Processing

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2013

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Vol. 49, iss. 2

659--672

EN

Influence of aqueous phase properties and process parameters on kaolinite particle zeta potential was quantified by electrophoresis experiments. The results indicated that pH strongly altered the zeta potential of kaolinite and it decreases at the beginning and then increases in the range of pH = 2–13. The activity of different cations changes the zeta potential and has the following tendency of Al3+ > Ca2+ > Mg2+ > Na+ and the zeta potential increases due to heterocoagulation of different mineral particles in suspension. It was found that the zeta potential of kaolinite particles increases after the suspension was stirred and decreases at the beginning, and then increases with soaking time. The FTIR results showed that the zeta potential takes into account ion adsorption and the change of Si–O, Al–O and Al–OH groups on the surface of the kaolinite particles.