In this paper, we propose a novel image indexing and retrieval algorithm using local tetra patterns (LTrPs) for content-based image retrieval (CBIR). The standard local binary pattern (LBP) and local ...ternary pattern (LTP) encode the relationship between the referenced pixel and its surrounding neighbors by computing gray-level difference. The proposed method encodes the relationship between the referenced pixel and its neighbors, based on the directions that are calculated using the first-order derivatives in vertical and horizontal directions. In addition, we propose a generic strategy to compute nth-order LTrP using (n - 1)th-order horizontal and vertical derivatives for efficient CBIR and analyze the effectiveness of our proposed algorithm by combining it with the Gabor transform. The performance of the proposed method is compared with the LBP, the local derivative patterns, and the LTP based on the results obtained using benchmark image databases viz., Corel 1000 database (DB1), Brodatz texture database (DB2), and MIT VisTex database (DB3). Performance analysis shows that the proposed method improves the retrieval result from 70.34%/44.9% to 75.9%/48.7% in terms of average precision/average recall on database DB1, and from 79.97% to 85.30% and 82.23% to 90.02% in terms of average retrieval rate on databases DB2 and DB3, respectively, as compared with the standard LBP.
We present 3-D simulations of wormhole formation in carbonate rocks using a two-scale continuum model. We employ the multigrid technique to obtain accurate solution of the model and analyze wormhole ...patterns in various acidization regimes. We also present a sensitivity analysis of the dissolution process with respect to acid injection rate, dissolution rate constant and rock properties such as initial average permeability, heterogeneity and permeability–porosity relationships. Finally, we determine the wormhole properties such as tip diameter and fractal dimension and compare the simulation results with available experimental data.
The effect of heterogeneity magnitude on wormhole pattern (a) Δε0=0.01 and (b) Δε0=0.1. A low heterogeneity (Δε0=0.01) leads to a smooth wormhole. As the heterogeneity magnitude is increased (Δε0=0.10) the wormhole becomes branched and fractal in nature. Display omitted
▸ Scaling analysis is used to estimate wormhole tip diameter. ▸ The dependence of the optimum injection rate on rock properties is estimated. ▸ The structure of the wormhole is computed under various conditions. ▸ Sensitivity of wormhole properties with respect to rock properties is presented.
Identification of 2,6-diisopropylphenol by Raman spectroscopy using the TruScan Raman spectrum is validated by specificity test and robustness. HPLC assay method is developed to detect the ...2,6-diisopropylphenol and its impurities A = determination of 2,6-diisopropylphenol; its main impurities related compound A = 2,6-diisopropylphenyl isopropyl ether, related compound B = 2,6-diisopropylquinone, and related compound C = 3,3'-5,5'-tetraisopropyl diphenol; and unknown impurities done by HPLC method. Related compound A and C determination has been developed by normal phase HPLC; good resolution peak shapes have resulted from the peak results. The limit of impurities A and C is reported to be 0.05% and 0.03%, and the limit of impurity B is also detected by using the same above procedure, but the column has been changed for the maximum wavelength detection and better elution from the peak results. The reported impurity level was 0.02%, the unknown impurity limit was 0.0149%, and the total impurity level of 2,6-diisopropylphenol was reported to be 0.06% which are in the threshold limit level. It specifies that the drug is safe and efficient without any toxicity.
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