• Economic and Environmental Geology
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• v.56 no.4
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• pp.409-419
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• 2023

Acid mine drainage(AMD) treatment is classified as both passive and active treatment. During the treatment, about 5,000 tons of neutralization sludge is generated as a by-product per year in Korea. This study was conducted to evaluate the characteristics of sludge generated from physico·chemical treatment processes as an active treatment from 5 different sources (D, H, S, T, Y) and the possibility of the sludges being recycled. The sludges have a pH range of 5.86 ~ pH 7.89, and a water content range of 51% ~ 82%. Most of particle sizes were less than 25 ㎛. In analysis of inorganic elements, the concentration of Al, Fe, and Mn were between 1,189 mg/kg ~ 129,344 mg/kg, 106,132 mg/kg ~ 338,011 mg/kg, and 3,472 mg/kg ~ 11,743 mg/kg, respectively. The concentration of As and Zn in sludge-T, Cd in sludge-D, Ni in sludge-H, Zn in sludge-S, and Cd in sludge-Y exceeded the soil contamination standards of Korea. The results from 2 separate kinds of leaching test, the Korea Standard Leaching Test(KSLT) and Toxicity Characteristic Leaching Procedure(TCLP), showed that all the sludges met the Korea groundwater standards. From the XRD and SEM-EDS analysis, the peaks of calcite and quartz were found in the sludges. The sludge also had a high proportion of Fe and O, and the majority of the composition was amorphous iron hydroxide.

• Korean Journal of Organic Agriculture
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• v.26 no.2
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• pp.281-296
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• 2018

This study was conducted to evaluate the effect of different processing of rice on rumen fermentation in in vitro and in situ experiments. Different processing treatments (extruding, roasting, and steaming) were used in this study and all treatments were ground through a cyclone mill (Foss, Hillerød, Denmark) fitted with a 1 mm screen. Non-treated rice was considered to a control substrate. Then, all treatments were used in in vitro and in situ experiments. Total gas production and dry matter digestibility in control were lower than any other treatment at all incubation times (P<0.01). The lowest ammonia nitrogen ($NH_3-N$) concentration was observed in control among treatments at 6, 12, and 24 h incubation (P<0.01). Extruding had a highest total volatile fatty acids (VFA) concentration at 6, 12 h incubation (P<0.01) and Steaming exhibited a highest total VFA at 24 h (P<0.01). The lowest total VFA concentration was observed in control at 6, 12, and 24 h (P<0.01). In an in situ, The highest value of soluble fraction, degradation rates, effective degradability was observed in extruding (P<0.01). It was considered that feed processing increased dry matter digestibility, total VFA concentration, and decreased pH as well as $NH_3-N$ concentration indicating that processing may increase nutrient degradation of rice in the rumen.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.545-551
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• 2017

Curcuma longa L. (CL) is widely used as a spice and coloring agent in several foods, such as curry and mustard, as well as cosmetics and drugs. In this study, we investigated the protective effects of CL extracted with various solvents [methanol (MC), ethanol (EC), acetone (AC)] on $H_2O_2-induced$ DNA damage in human leukocytes along with total polyphenol contents (TPC) and antioxidant properties. The antioxidant effects of CL were determined by measuring 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (RSA) and superoxide dismutase (SOD)-like activity. The preventive effect of CL on oxidative stress-induced DNA damage and DNA repair capacities were assessed using comet assay. MC showed the highest TPC (11.17 g gallic acid equivalents/100 g) and antioxidant properties among the solvent extracts. The $SC_{50}$ for DPPH RSA was MC: 35.0 > AC: 45.8 > EC: $57.8{\mu}g/mL$ and SOD-like activity was MC: 46.6 > EC: 141.5 > AC: $296.4{\mu}g/mL$. In the comet assay, the $ED_{50}$ value of MC showed the highest inhibition ($86.7{\mu}g/mL$) of $H_2O_2-induced$ DNA damage, followed by AC ($110.0{\mu}g/mL$) > EC ($115.8{\mu}g/mL$). Analysis of the percentage of damaged cells showed that repair capacity significantly decreased at 4, 8, and 12 h from $H_2O_2-induced$ oxidative stress in each extract. After 12 h, level of DNA damage recovery was similar to the negative control level. These results suggest that CL has potential antioxidant activity and a protective effect against oxidation-induced DNA damage, and the methanol extract of CL was the most effective.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1650-1656
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• 2011

A series of potent tricyclic derivatives with a non-aromatic amide as potent PARP-1 inhibitors were successfully synthesized and their PARP-1 inhibitory activity was evaluated. Among the derivatives, 2-(1-propylpiperidin-4-yloxy)-7,8,9,10-tetrahydrophenanthridin-6(5H)-one 23c displayed potent activity in a PARP-1 enzymatic assay and cell-based assay ($IC_{50}$ = 0.142 ${\mu}M$, $ED_{50}$ = 0.90 ${\mu}M$) with good water solubility. Further, molecular modeling studies confirmed the obtained biological results.

• Journal of Oriental Neuropsychiatry
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• v.23 no.3
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• pp.161-174
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• 2012

Objectives : The purpose of this study is to study as reference for practical application in clinics, examine the procedure of historical changes and compare components and their doses of herb medicines, which are recorded in the chapter, Sinmun Jeonkwang of "Donguibogam". Methods : I examined 19 Herb Medicines (Ed note: no need to capitalize the 'h' and 'm') in Chapter Sinmun Jeonkwang of "Donguibogam". Fourteen books, which were noted in Chapter Sinmun Jeonkwang of "Donguibogam" and 16 books in Jeonkwang part of "The Eastern Medical Textbook of neuropsychiatry" and 25 books were mentioned in same part of "Uibujeonrok", were selected as reference. Results and Conclusions : Fourteen documents were referred to the 19 Herb Medicines in Chapter Sinmun Jeonkwang of "Donguibogam". Seventeen Herb Medicines were recorded in the source book but 2 Herb Medicines were not recorded. Fourteen Herb Medicines among 19 were recorded in the source book, which were directly quoted from the firstly appeared books, and 3 Herb Medicines were re-quoted from the other books that succeeded the source books. I suspect that the components and dosages of the Herb Medicines were revised, according to the author's clinical experience and circumstances.

• Structural Engineering and Mechanics
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• v.17 no.3_4
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• pp.393-408
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• 2004

There exists a clear need to monitor the performance of civil structures over their operational lives. Current commercial monitoring systems suffer from various technological and economic limitations that prevent their widespread adoption. The wires used to route measurements from system sensors to the centralized data server represent one of the greatest limitations since they are physically vulnerable and expensive from an installation and maintenance standpoint. In lieu of cables, the introduction of low-cost wireless communications is proposed. The result is the design of a prototype wireless sensing unit that can serve as the fundamental building block of wireless modular monitoring systems (WiMMS). An additional feature of the wireless sensing unit is the incorporation of computational power in the form of state-of-art microcontrollers. The prototype unit is validated with a series of laboratory and field tests. The Alamosa Canyon Bridge is employed to serve as a full-scale benchmark structure to validate the performance of the wireless sensing unit in the field. A traditional cable-based monitoring system is installed in parallel with the wireless sensing units for performance comparison.

• Structural Engineering and Mechanics
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• v.15 no.3
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• pp.285-297
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• 2003

Complementing recent advances made in the field of structural health monitoring and damage detection, the concept of a wireless sensing network with distributed computational power is proposed. The fundamental building block of the proposed sensing network is a wireless sensing unit capable of acquiring measurement data, interrogating the data and transmitting the data in real time. The computational core of a prototype wireless sensing unit can potentially be utilized for execution of embedded engineering analyses such as damage detection and system identification. To illustrate the computational capabilities of the proposed wireless sensing unit, the fast Fourier transform and auto-regressive time-series modeling are locally executed by the unit. Fast Fourier transforms and auto-regressive models are two important techniques that have been previously used for the identification of damage in structural systems. Their embedment illustrates the computational capabilities of the prototype wireless sensing unit and suggests strong potential for unit installation in automated structural health monitoring systems.

• Journal of Powder Materials
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• v.12 no.4 s.51
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• pp.291-295
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• 2005

CdSe hollow sphere with average size of about 30-50 nm was synthesized from the mixed solution of cadmium chloride $(CdCl_2)$, sodium selenosulfate $(Na_2SeSO_3)$ and ethylenediamine(EDA, $H_2NCH_2CH_2NH_2$) at room temperature. The molar ratio of EDA to $Cd^{2+}$ showed the most significant effect on the morphology of CdSe hollow sphere. This paper will present and discuss the possible formation mechanism of CdSe hollow sphere based on the observation of morphological changes.

• Journal of the Korean Mathematical Society
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• v.48 no.4
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• pp.837-847
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• 2011

For an integer $m{\geq}3$, every integer of the form $p_m(x)$ = $\frac{(m-2)x^2(m-4)x}{2}$ with x ${\in}$ $\mathbb{Z}$ is said to be a generalized m-gonal number. Let $a{\leq}b{\leq}c$ and k be positive integers. The quadruple (k, a, b, c) is said to be universal if for every nonnegative integer n there exist integers x, y, z such that n = $ap_k(x)+bp_k(y)+cp_k(z)$. Sun proved in [16] that, when k = 5 or $k{\geq}7$, there are only 20 candidates for universal quadruples, which h listed explicitly and which all involve only the case of pentagonal numbers (k = 5). He veri ed that six of the candidates are in fact universal and conjectured that the remaining ones are as well. In a subsequent paper [3], Ge and Sun established universality for all but seven of the remaining candidates, leaving only (5, 1, 1, t) for t = 6, 8, 9, 10, (5, 1, 2, 8) and (5, 1, 3, s) for s = 7, 8 as candidates. In this article, we prove that the remaining seven quadruples given above are, in fact, universal.

• 한국해양학회지
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• v.16 no.1
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• pp.12-23
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• 1981

A numerical experiment is made in order to clarify the mechanism of the upwelling phenomenon along the coast near the poleward edge of the western boundary current. The possibility of the upwelling is suggested from the analysis of the observational data in the east of Honshu, Japan, and in the south eastern coast of Korean Peninsula. This upwelling phenomenon is very deep and can be traced to the bottom layer. The upwelling phenomenon seems to be a general oceanic feature which characterizes the region along the west coast near the poleward edge of the western boundary current. This experiment is simulating the oceanic condition of the transition region between Kuroshio front and the Oyashio front in the east of Honshu, Japan. The possible explanations of the causes of the upwelling are as follows;In the interior of the modeled ocean the cold heavy water supplied from the north and the warm light water from the south make the north-south gradient of the pressure field and accelerate the eastward current to produce the h-orizontal divergence feld near the west coast. The divergence is compensated by the upwelling near the separation region. Another one is that the upwell-ed cold water strengthen constantly the pressure gradient which is balanced by the northward current and is weakened by the horizontal diffusion.