Roughness and granularity measures using Hausdorff metric: a new approach

Measures for uncertainty due to approximation of sets in rough set theory are accuracy and roughness. In determining these quantities, the cardinality of a set is always used and never the numerical values of the attributes (if they exist) of elements in the sets. Therefore, distances between the exact set and the corresponding upper and lower approximations can give a better quantitative measure of the roughness. Here, we propose a measure based on Hausdorff metric which takes into account the distance between two sets, the exact set and its two approximations (lower and upper). Using this measure, we can quantify the uncertainty of a rough set based on the values in the domain of sample points but not on the basis of number of sample points. Also, we propose a new measure for granulation which is again based on the Hausdorff metric. The effectiveness of the proposed measures is demonstrated on a synthetic data.     

Artificial neural network modeling to evaluate and predict the deformation behavior of stainless steel type AISI 304L during hot torsion

The deformation behavior of type 304L stainless steel during hot torsion is investigated using artificial neural network (ANN). Torsion tests in the temperature range of 600–1200 °C and in the (maximum surface) strain rate range of 0.1–100 s^?1 were carried out. These experiments provided the required data for training the neural network and for subsequent testing. The input parameters of the model are strain, log strain rate and temperature while torsional flow stress is the output. A three layer feed-forward network was trained with standard back propagation (BP) and Resilient propagation (Rprop) algorithm. The paper makes a robust comparison of the performances of the above two algorithms. The network trained with Rprop algorithm is found to perform better and also needs less number of iterations for convergence. The developed ANN model employing this algorithm could efficiently track the work hardening, dynamic softening and flow localization regions of the deforming material. Sensitivity analysis showed that temperature and strain rate are the most significant parameters while strain affects the flow stress only moderately. The ANN model, described in this paper, is an efficient quantitative tool to evaluate and predict the deformation behavior of type 304L stainless steel during hot torsion.     

BILEAT: a highly generalized and robust approach for unified aspect-based sentiment analysis

Applied Intelligence - Aspect-based sentiment analysis (ABSA) includes two subtasks, namely, aspect term extraction and aspect-level sentiment classification. Most existing works address these...     

Secondary crystallization and premelting endo‐ and exotherms in oriented polymers

Crystallization in polyamide 6 (nylon 6) fibers during annealing was studied in detail by following the changes that occurred in the neighborhood of crystalline relaxation temperatures, by using wide‐ and small‐angle X‐ray scattering and differential scanning calorimetry (DSC). Two distinct crystallization regimes were observed depending on whether annealing was carried out below or above onset of crystalline relaxation at ～190°C. In fibers annealed below 190°C, minor melting peaks were followed by exothermic transitions. These were attributed to ～1.5% (by weight) of microcrystals formed during annealing that melt and recrystallize during the DSC scan. These microcrystals are nucleated from unoriented amorphous chains between the lamellar stack within a fibril, and are shown to account for the observed increase in the crystalline orientation and decrease in permeability. Fibers annealed above 190°C did not show the exotherm and had significantly fewer microcrystals. The crystallization in this regime was attributed to the growth of existing lamellae, as evidenced by the increase in crystallite size, crystalline density, crystalline orientation, lamellar spacing, and lamellar intensity. The changes at annealing temperatures >190°C are accompanied by increased dyeability, indicative of more open amorphous regions. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 447–454, 2006     

Microstructure dependent erosion in Cr3C2-20(NiCr) coating deposited by a detonation gun

Cr₃C₂-20(NiCr) coating powder was deposited on a low carbon steel by pulsed detonation spray gun technique. The coated samples were heat-treated at 600 °C for 11/2 h and allowed to cool in air. A systematic microstructural study was carried out using SEM and TEM to understand the microstructural changes. The mechanical properties like hardness, indentation fracture toughness and adhesion strength of the coating in the as-sprayed and heat-treated conditions were also determined. The change in solid particle erosion of the coating was correlated with the microstructural and subsequent mechanical property changes. It was observed that exposure of the as-sprayed coating to elevated temperature improves the wear resistance. It is concluded that crystallisation of the amorphous phase into nanocrystalline composite combined with better bonding between the adjacent splats through sintering contributes to improved hardness, fracture toughness and wear resistance of the heat-treated coating. The deformation characteristics of the binder phase, amorphous vis-à-vis crystalline, also influence the wear behaviour of the coating.     

Nitrided and carbided magnets

In this article, we review our recent studies on new rare-earth intermetallic compounds including the Ga, Si substituted 2:17-type compounds, their nitrides, carbides, and the Sm₃ (Fe,Ti)₂₉N₅ compounds. Much of our recent work is focused on the Sm₂(Fe,Ga)₁₇C_x alloys where we used melt spinning and subsequent annealing to obtain high coercivity. The highest coercivity obtained so far was in Sm₂Fe₁₄Ga₃C_2.5 with a value of 12.8 kOe at room temperature. The off-stoichiometric Sm₂Fe_14-xCo_xSi₂N_y nitrides maintain the Th₂Zn₁₇-type structure but with a unit-cell expansion ΔVV up to 5 % compared to the host materials. The Sm₂Fe_14-xCo_xSi₂C_z carbides maintain the Tr₂Zn₁₇-type structure when z = 1 and transform to the BaCd₁₁-type structure when z = 2. A very large anisotropy field with an applied magnetic field (H_a) value of 227 kOe for Sm₂Fe₁₄Si₂N_2.6 and 276 kOe for Sm₂Fe₁₀Co₄Si₂N_2.3 is observed at low temperature (1.5 K). The Sm₃(Fe,Ti)₂₉N₅ compound and its nitrides show very interesting magnetic properties. Both of these compounds exhibit ferromagnetic ordering with Curie temperature (T_c) of 486 and 750 K, respectively. The room temperature saturation magnetization is 119 emu/g for the parent compounds and 145 emu/g for the nitrides. The easy magnetization direction changes from planar to uniaxial upon nitrogenation. The anisotropy field for the nitrides is 12 T at room temperature and 25 T at 4.2 K.     

Large‐Scale Fabrication of MoS2 Ribbons and Their Light‐Induced Electronic/Thermal Properties: Dichotomies in the Structural and Defect Engineering

Controlled design and patterning of layered transition metal dichalcogenides (TMDs) into specific dimensions and geometries hold great potential for next‐generation micro/nanoscale electronic applications. Herein, the large‐scale fabrication of MoS₂ ribbons with widths ranging from micro‐ to nanoscale is reported. Their unique electric and thermal properties introduced by the shape change and defect creation are also demonstrated, with particular focus on the performance associated with light–matter interactions. The theoretical calculation indicates significantly increased absorption and scattering efficiency of the MoS₂ ribbons with decreasing width. As a result, enhanced photocarrier generation ability is detected on their phototransistors with defect‐modulated light‐response behavior. The light‐induced thermal transport properties of the MoS₂ ribbons are further studied. A decreased thermal conductivity is observed on narrower ribbons, attributed to the defects created during fabrication. It is also found that the effect of phonon scattering at ribbon edges on their thermal conductivity is insignificant, and the thermal transport has no obvious dependence on the ribbon direction at such width scale. This study evaluates the prospects for designing and fabricating TMD semiconductors with specific geometries for future optoelectronic applications.     

Genetic loadings in schizophrenia: a dermatoglyphic study

Finger and palmar dermatoglyphics of 120 male and 120 female schizophrenics with and without a family history of schizophrenia in first-degree relatives were studied in the northwestern part of India. Patients were selected according to specific diagnostic criteria. Significant dermatoglyphic differences were observed for fingerprint patterns, total finger ridge counts and 'atd' angle between the schizophrenics with and those without a positive family history of schizophrenia, suggesting a strong "genetic loading" (i.e., hereditary factors) in familial cases of schizophrenia. Dermatoglyphic features of isolated schizophrenics also significantly differed from those of controls, thus indicating the involvement of genetic factors in the etiology of schizophrenia.     

Constitution and properties of phosphosilicate coatings

The constitution and structure of sodium phosphosilicate coatings were investigated by paper chromatography, X-ray diffraction, and infrared spectroscopy. All the tests performed indicated that heating phosphosilicate coating samples resulted in the polymerization of the silicate to crystalline silica (-crystobalite) while the phosphate depolymerized. The extent of the depolymerization of the phosphate depended on the total Na₂O in the phosphosilicate system. The assumption that the maximum quantity of Na₂O in the phosphosilicate system, up to a molar ratio of 31 Na₂OP₂O₅, associates with the phosphate, gave a good estimate of the phosphate chain distribution in the phosphosilicate system.