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The incomplete datasets with missing values are unsuitable for making strategic decisions since they lead to biased results. This problem is even worse when the dataset is large and collected from many heterogeneous sources. The paper deals with missing scenarios which were not dealt together earlier. The proposed Dual Repopulated Bayesian Ant Colony Optimization (DPBACO) handles both ignorable and non-ignorable missing values in heterogeneous attributes of large datasets The DPBACO integrates Bayesian principles with Ant Colony Optimization technique since both are simple and efficient to implement. After pheromone updation, repopulation of the solution pool is done by dividing the population into two based on their fitness values and generating new offsprings by performing crossover operation. The DPBACO algorithm is implemented on six large mixed-attribute datasets for imputing both kinds of missing values. The empirical and statistical results show that DPBACO performs better than other existing methods at variable missing rates ranging from 5% to 50%. [ABSTRACT FROM AUTHOR]

• Proposes Tri-Staged Feature Selection (TFS) for multi-class heterogeneous datasets. • Initial features are selected using Kruskal Wallis Test. • Refinement of obtained features using Memetic Algorithm with local beam search. • Final feature set refinement using Cuckoo search algorithm for better classification. • Experiments conducted on 12 real datasets for validation of proposed method. Classification algorithms and their preprocessing operations usually performs on feature selection on homogeneous or heterogeneous attributes, binary or multi-class labels separately. Only very few methods attempt to perform feature selection on datasets with heterogeneous multi-class attributes. In order to bridge this gap with better classification performance, the paper proposes a Tri-staged Feature Selection (TFS) methodology which performs (i) Feature selection using Kruskal Wallis test (ii) Refinement of feature selection using a new Memetic Algorithm with local beam search and genetic algorithm operations and (iii) Further refinement of feature selection using Cuckoo Search algorithm. Proper tradeoff between both exploration and exploitation is maintained in the proposed method. The experimental results on 12 datasets show that the proposed method is better than that of state-of-the-art methods used for feature selection in terms of multi-class accuracy, hamming loss, ranking loss, normalized coverage and convergence rate for multi-class heterogeneous datasets. [ABSTRACT FROM AUTHOR]

Abstract: A study has been carried out to analyze the effects of variable electric conductivity, non-uniform heat source/sink and higher order chemical reaction on unsteady, free convective viscoelastic (Walters liquid model-B) fluid flow over a moving vertical cone and a flat plate saturated with porous medium. The constitutive equations for the boundary layer regime are solved by an efficient finite difference scheme of the Crank-Nicolson type. The features of the fluid flow, heat and mass transfer characteristics are analyzed by plotting graphs and the physical aspects are discussed in detail to interpret the effect of various significant parameters of the problem. It is observed that the impact of variable electric conductivity with magnetic field has significant effect on the viscoelastic fluid flow through porous medium. The effect of temperature dependent heat generation is much stronger than the effect of surface dependent heat generation. The mass transfer of the reactive species strongly depends on the chemical reaction parameter as well as the order of chemical reaction. It is stronger for the first-order reaction than that for the higher order reaction. [Copyright &y& Elsevier]

Abstract: The present paper is concerned with the study of flow, heat and mass transfer characteristics in the unsteady free convective flow of an incompressible viscoelastic fluid over a moving vertical cone and a flat plate in the presence of magnetic field and higher order chemical reaction. The fluid viscosity and thermal conductivity are assumed to vary as a linear function of temperature. The governing partial differential equations are solved numerically using the implicit finite difference method of Crank–Nicolson type. The features of the fluid flow, heat and mass transfer characteristics are analyzed by plotting graphs and the physical aspects are discussed in detail. The results obtained show that the impact of magnetic field, buoyancy ratio parameter, viscosity variation parameter, Ecart number and chemical reaction parameter plays an important role in the viscoelastic fluid flow through porous medium. The mass transfer of the reactive species strongly depends on the chemical reaction parameter as well as the order of chemical reaction. [Copyright &y& Elsevier]

Abstract: A study has been carried out to analyze the double dispersion effects on unsteady, free convective, chemically reacting, MHD viscoelastic fluid (Walters liquid-B model) flow over a vertical cone and a flat plate saturated with non-Darcy porous medium in the presence of Soret and Dufour effects. The constitutive equations for the boundary layer regime are solved by an efficient finite difference scheme of the Crank-Nicolson type. The features of the fluid heat and mass transfer characteristics are analyzed by plotting graphs and the physical aspects are discussed in detail to interpret the effect of significant parameters of the problem. The overall heat and mass transfer profiles are enhanced for increasing the thermal and solutal dispersion effects, respectively. The results indicate that the Soret and Dufour effects have considerable effect on the viscoelastic fluid flow through non-Darcy porous medium. [Copyright &y& Elsevier]

Abstract: The present investigation deals with the study of unsteady, MHD, heat absorbing and chemically reacting dusty viscoelastic (Walter’s liquid model-B) fluid Couette flow between vertical long wavy wall and a parallel flat wall saturated with porous medium subject to convective cooling and varying mass diffusion. The perturbation method is employed to analyze the coupled equations involving nonlinear problem and solution for the velocity, temperature and concentration distributions are obtained analytically. The graphical results are presented and the physical aspects are discussed in detail to interpret the effect of various significant parameters of the problem. The effect of the skin-friction, rate of heat and mass transfer coefficients at the channel walls are tabulated. [Copyright &y& Elsevier]

Aluminium ions are present in the human body and in the environment. Chemo-sensing of mobile aluminium ions is hence vital, and in this paper we report two isomeric 4-aminoantipyrine derivatives, as turn–on fluorescent Al 3+ ion sensors. The compounds are synthesized as simple Schiff bases and characterized using UV–visible, IR, 1 H NMR, 13 C NMR and Mass spectroscopy. Selectivity of aluminium ions is displayed by the receptors when screened for binding against a pool of metal ions, and the magnitude of selectivity differs between the two chemo-sensors. The chemo-sensors show visible colour changes when binding Al 3+ ions through PET (Photoinduced Electron Transfer) which make them colorimetric sensors. We propose the binding strength and the mode of binding of the metal ion to the chemo sensors. Further, the molecular logic behaviour of chemo-sensors with proton and Al 3+ ions as inputs is also explored. [ABSTRACT FROM AUTHOR]