• Resources Recycling
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• v.30 no.4
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• pp.11-19
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• 2021

Arsenic (As) oxidation followed by precipitation from a high-As(III)-containing leaching solution derived from a sulfidic ore was investigated in this study to remove aqueous As from the solution using activated carbon (AC) with air injection as an oxidant. To obtain the initial leaching solution, a domestic sulfidic ore was leached in a sulfuric acid solution at pH 1 and 50℃ for 95 h, and approximately 7 g/L of Fe and 3 g/L of As were leached out. To determine the effect of the oxidative reaction utilizing AC with air injection, the leaching solution was tested under the following five oxidative conditions at an initial pH of 1 and 90℃ for 72 h: air-only injection; air injection with 1, 5, and 10 w/v% of AC addition; and H₂O₂ addition. The tests in the presence of both air and AC revealed that the oxidation kinetics and As removal were improved by the reaction between the metallic species and the surface group formed on the AC surface. In addition, the greater the amount of AC added, the better was the reaction efficiency, removing 93-94% of As with more than 5 w/v% of AC addition. Finally, X-ray diffraction analysis confirmed that the precipitate formed from the oxidative reaction was scorodite (FeAsO₄·2H₂O).

• Journal for History of Mathematics
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• v.27 no.4
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• pp.285-297
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• 2014

G. H. Hardy laid the foundation of classical studies on double Fourier series at the beginning of the 20th century. In this paper we are concerned not only with Fourier series but more generally with trigonometric series. We consider Norlund means and Cesaro summation method for double Fourier Series. In section 2, we investigate the classical results on the summability and the convergence of double Fourier series from G. H. Hardy to P. Sjolin in the mid-20th century. This study concerns with the $L^1(T^2)$-convergence of double Fourier series fundamentally. In conclusion, there are the features of the classical results by comparing and reinterpreting the theorems about double Fourier series mutually.

• Communications of the Korean Mathematical Society
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• v.23 no.4
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• pp.597-606
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• 2008

Let {$Y_{ij}-{\infty}\;<\;i\;<\;{\infty}$} be a doubly infinite sequence of identically distributed and ${\rho}^*$-mixing random variables with zero means and finite variances and {$a_{ij}-{\infty}\;<\;i\;<\;{\infty}$} an absolutely summable sequence of real numbers. In this paper, we prove the complete moment convergence of {${\sum}^n_{k=1}\;{\sum}^{\infty}_{i=-{\infty}}\;a_{i+k}Y_i/n^{1/p}$; $n\;{\geq}\;1$} under some suitable conditions. We extend Theorem 1.1 of Li and Zhang [Y. X. Li and L. X. Zhang, Complete moment convergence of moving average processes under dependence assumptions, Statist. Probab. Lett. 70 (2004), 191.197.] to the ${\rho}^*$-mixing case.

• KSBB Journal
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• v.31 no.1
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• pp.27-32
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• 2016

Several CoA transferases from Clostridium beijerinckii, C. perfringens and Klebsiella pneumoniae were examined for biosynthesis of lactate-containing polyhydroxyalkanoates (PHAs) in recombinant Escherichia coli XL1-Blue strain. The CB3819 gene and the CB4543 gene from C. beijerinckii, the pct gene from C. perfringens and the pct gene from K. pneumoniae, which encodes putative CoA transferase gene, respectively, was co-expressed with the Pseudomonas sp. MBEL 6-19 phaC1437 gene encoding engineered Pseudomonas sp. MBEL 6-19 PHA synthase 1 ($PhaC1_{Ps6-19}$) to examine its activity for the construction of key metabolic pathway to produce poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)]. The recombinant E. coli XL1-Blue expressing the phaC1437 gene and CB3819 gene synthesized poly(3-hydroxybutyrate) [P(3HB)] homopolymer to the P(3HB) content of 60.5 wt% when it was cultured in a chemically defined medium containing 20 g/L of glucose and 2 g/L of sodium 3-hydroxybutyrate. Expression of the phaC1437 gene and CB4543 gene in recombinant E. coli XL1-Blue also produced P(3HB) homopolymer to the P(3HB) content of 51.2 wt% in the same culture condition. Expression of the phaC1437 gene and the K. pneumoniae pct gene in recombinant E. coli XL1-Blue could not result in the production of PHAs in the same culture condition. However, the recombinant E. coli XL1-Blue expressing the phaC1437 gene and the C. perfringens gene could produce poly(3-hydroxybutyrate-co-lactate [P(86.4mol%3HB-co-13.7 mol%LA) up to the PHA content of 10.6 wt% in the same culture condition. Newly examined CoA transfereases in this study may be useful for the construction of engineered E. coli strains to produce PHA containing novel monomer such lactate.

• The Korean Journal of Food & Health Convergence
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• v.5 no.3
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• pp.1-5
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• 2019

The field experiment was conducted in vegetable area, Institute of Horticultural Sciences in University of Agriculture, Faisalabad in order to recognize morphological and fruit growth pattern and yield of Tinda (Praecitrullus fistulosus) gourd germplasm lines. Sixteen germplasm lines in which one line is used as check are included were sown and grown on flat beds in field. The field experiment was arranged as randomized complete block design (RCBD) with three replications. Data on days to maturity, fruit per vine, fruit weight in grams, fruit diameter and total yield obtained were recorded. The fruit texture is marked as phenotype parameter. All parameters were collected and then analyzed statistically. All lines and replications showed different results among each other according to parameter. The maximum DTM (days to maturity), F/P (fruit per plant), FW (fruit weight), FD (fruit diameter) and Yield were recorded was $L_0$ (68.66), $L_3$ (1.66), $L_{10}$ (248.33), $L_{13}$ (8.50) and $L_0$ (599.33) and the minimum were recorded was $L_1$ (56), $L_{11}$ (0.33), $L_0$ (198), $L_9$ (7) and $L_4$ (421) grams respectively. All lines showed smooth texture of fruits with no hairs when mature at harvesting stage.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.4_2
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• pp.699-706
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• 2022

In this study, Directed energy deposition (DED) among additive manufacturing is applied to repair damaged spindle key parts of planner miller. The material of the spindle key is SCM415, and the P21 Powder is used. In order to find the optimal deposition conditions for DED equipment, a single-line deposition experiment is conducted to analysis five parameters. The laser power affects the width, and the height is a parameter affected by coaxial gas and powder gas. In addition, laser power, powder feed rate, coaxial gas, and powder gas are parameters that affect dilution. Otimal deposition is that 400 W of laser power, 4.0 g/min of powder feed rate, 6.5 L/min of coaxial gas, 3.0 L/min of powder gas and 4.5 L/min of shield gas. By setting the optimum conditions, a uniform deposition cross section in the form of an ellipse can be obtained. Damage recovery process of spindle key consists of 3D shape design of the base and deposition parts, deposition path creation and deposition process, and post-processing. The hardness of deposited area with P21 powder on the SCM415 spindle key is 336 HV for the surface of the deposition, 260 HV for the boundary area, and 165 HV for the base material.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.12 no.3
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• pp.133-137
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• 2008

We prove an extended version of asymptotic behavior of the orthonormal cardinal refinable functions from Blaschke products introduced by Contronei et al [2]. In fact, we show the orthonormal cardinal refinable function ${\varphi}_{k,q}$ converges in $L^p(\mathbb{R})$ ($2{\leq}p{\leq}{\infty}$) to the Shannon refinable function as ${\kappa}{\rightarrow}{\infty}$ uniforml on a class $\mathcal{Q}_{A,B}$ of real symmetric polynomials determined by positive constants $A{\leq}B$.

• Bulletin of the Korean Mathematical Society
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• v.38 no.2
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• pp.237-260
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• 2001

The approximation properties for $L^2$-projection, Raviart-Thomas projection, and inverse inequality have been derived in 3 dimensional space. h-p-mixed finite element methods for strongly nonlinear second order elliptic problems are proposed and analyzed in 3D. Solvability and convergence of the linearized problem have been shown through duality argument and fixed point argument. The analysis is carried out in detail using Raviart-Thomas-Nedelec spaces as an example.

• Journal of the Korean Mathematical Society
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• v.45 no.1
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• pp.177-196
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• 2008

Using the results on the coefficients of Hermite-Fej$\acute{e}$r interpolations in [5], we investigate convergence of Hermite and Hermite-$Fej{\acute{e}}r$ interpolation of order m, m=1,2,... in $L_p(0<p<{\infty})$ and associated product quadrature rules for a class of fast decaying even $Erd{\H{o}}s$ weights on the real line.

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.1009-1015
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• 2022

The purpose of this study was to investigate the effects of protease in Letinus edodes, Agaricus bisporus and Pear powder after freeze drying which has the ratio of 3% on the Tenderness of the Beef Eye of Round muscle. It were marinated in distilled water (Control), 3% Letinus edodes powder (L3), 3% Agaricus bisporus powder (A3), and 3% Pear powder (P3). As a result, enzyme activities were highest in Agaricus bisporus (p<0.001). There are significant difference in pH (p<0.001), color of the beef were slightly different between the C (control) group and the sample groups. The cooking loss showed the lowest value in the control and the highest value in the water holding capacity of Agaricus bisporus. In addition, Agaricus bisporus showed the lowest shear force values than the other sample groups(p<0.001).