• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.5
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• pp.467-475
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• 2013

In order to seize quantitative materials as part of studies on measures for oil pollution prevention and control, the statistics of oil pollution incidents in Korean coastal waters for 10 years from 2003 to 2012 were analyzed with relation to the number of oil spills and the volume of oil spilt according to causes, sources and sea areas of spills. Total number and total volume of oil spills for 10 years were found to be 2,833 cases and 17,877 kL, respectively. 50.4 %(1,429 cases) of total number of oil spills were caused by negligence, although oil spillage due to negligence was 294 kL(1.7 %). While oil spillage caused by marine accidents was 17,400 kL(97.3 %), marine accidents accounted for 27.9 %(790 cases) of total number of oil spills. While negligence had a great influence on the number of oil spills, marine accidents had a huge impact on the amount of oil spilt. Fishing boats accounted for 42.7 %(1,210 cases) of the number of oil spills, and although oil tankers accounted for 9.2 %(261 cases) of the number of oil spills, oil spillage from oil tankers was 15,488kL(86.7 %). It means that oil tankers such as VLCC or ULCC may be the main sources of major oil spills and a few very large spills are responsible for a high percentage of the amount of oil spilt. While the number of oil spill incidents was closely related to the accidents of fishing boats, the volume of oil spilt was greatly affected by the major oil spill incidents of oil tankers such as M/T Hebei Spirit. The number and volume of oil spills were shown to be 1,613 cases(56.9 %) and 3,804 kL(21.3 %) in South Sea, 700 cases(24.7 %) and 13,501 kL(75.5 %) in West Sea, and 520 cases(18.2 %) and 572 kL(3.2 %) in East Sea of Korea, respectively. The highest number of oil spills was found in South Sea and the most volume of oil spilt was shown in West Sea of Korea for 10 years.

• Korean Journal of Plant Tissue Culture
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• v.21 no.3
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• pp.131-135
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• 1994

This experiment was designed to improve the in vitro production system of apple rootstock M.26 as being influenced by the growth regulators, TDZ, BA, IAA, IBA, zeatin, and GA$_3$. Different levels of potassium humate (KH), known as cytokinin and auxin-like substance, were also supplemented to the MS basal medium along with IBA 0.6 mg/L to find out it effect on root formation in apple rootstock M.26. ID initiate and establish the in vitro multiplication of shoots byway of meristem culture, MS medium added with zeatin 1.0 mg/L was found to be the most suitable, showing the 100% of survival rate of shoot tips. A combination of thidiazuron (TDZ) 0.2 mg/L and NAA 0.5 mg/L promoted the shoot proliferation when shoot tips were used as explants. MS basal medium plus IBA 0.6 mg/L was very effective for root induction, but an addition of potassium humate (250 mg/L) to the medium containing IBA 0.6 mg/L stimulated the induction and proliferation of the rook by far the better.

• Korean Journal of Plant Resources
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• v.18 no.1
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• pp.57-63
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• 2005

In order to develop the mass production method of anticancer compound-polyacetylene from tissue culture of Panax ginseng C.A. Mayor, these studies were carried out for the effects of various chemicals used as precursor and elicitor in viかo. Ginseng callus cultured on the growth medium containing 5mg/l L-phenylalanine was well grown and detected polyacetylene compounds as well as panaxydol and panxynol. But same media containing $\alpha-methyl-D.L.methionine$ and D.L.-norleucine was not detected any polyacetylene. Panaxydol, one of polyacetylene and active anticancer compound, was detected in calli cultured on media with upper 1mg/l chitosan used as elicitor, but panaxynol was not detected. Nigeran used as active elicitor, caused to decrease the growth of ginseng callus, and don't work as elictor on the biosynthesis of polyacetylene from ginseng callus.

• KSBB Journal
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• v.23 no.2
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• pp.135-141
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• 2008

SMB (simulated moving bed) chromatography is a very useful utility for the separation of binary system. We simulated the separation of L-arabinose and L-ribose from the mixture by using lab-scale 4(1-1-1-1)-zone SMB chromatography. Preliminary experiments of PIM (pulse input method) were performed to measure adsorption isotherms of L-ribose and L-arabinose in $NH_2$ HPLC column, and experimental and simulated results from ASPEN chromatography were compared. To find the most suitable separation condition in SMB, we carried out a simulation in $m_2-m_3$ plane base on the triangle theory and calculated operating parameters (flow rate of four zone, switching time and feed concentration and so on) using ASPEN chromatography under the conditions of linear isotherms obtained from PIM.

• Proceedings of the KSAR Conference
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• 2001.03a
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• pp.88-88
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• 2001

소 난포란을 체외에서 성숙, 수정시킨 후, 2~8 세포기 수정란을 체외배양액인 CR$_1$aa에 일정량의 nitric oxide scavenger, Hb와, inhibitor인 L-nitro - L- arginine methyl ester (L-NAME)를 첨가 배양하여 체외발육에 미치는 영향을 검토하고자 실시하였다. 체외수정 후 체외배양 48시간에 난구세포의 제거 유.무에 따라 CR$_1$aa 배양액에 hemoglobin을 0, 1, 5$\mu\textrm{g}$/$m\ell$를 첨가한 구의 상실배기이상 체외발육성적은 난구세포를 제거한 구에서 23.8%, 33.3% 및 26.8%였으며, 난구세포를 제거하지 않은 구에서는 각각 39.5%, 54.8% 및 48.8%로써 난구세포를 제거하지 않은 구에 Hb를 1$\mu\textrm{g}$/$m\ell$를 첨가한 구가 여타구 보다 통계적으로 높은 결과를 얻었다(P<0.05). 체외수정 후 체외배양 96시간 후 난구세포를 제거 유.무에 따라 Hb를 0, 1, 5$\mu\textrm{g}$/$m\ell$를 첨가하였을 때, 상실배기 이상 체외발육성적은 난구세포를 제거한 구에서 각각 28.6%, 46.2% 및 39.1%였으며, 난구세포를 제거하지 않은 구에서는 각각 33.9%, 67.2% 및 46.0%로써, 난구세포를 제거하지 않은 구에 Hb를 1$\mu\textrm{g}$/$m\ell$첨가구가 여타구에 비해 통계적으로 유의하게 높게 나타났다( P<0.05).CR$_1$aa배양액에 L-NAME를 0, 10, 50 및 100mM을 첨가한 구에서 상실배이상 발육된 체외발육성적은 각각 55.6%, 64.9%, 58.8% 및 66.7%로써 L-NAME 첨가구가 무첨가구에 비해 커다란 차이가 나타나지 않았다(P>0.05). 본 실험의 결과로 볼 때, nitric oxide scavenger인 hemoglobin의 첨가는 체외수정 후 체외배양 96시간에 1$\mu\textrm{g}$/$m\ell$ 첨가하는 것이 체외수정란의 체외 발육율을 향상시켰으며, nitric oxide inhibitor인 L-NAME는 첨가 농도에 관계없이 체외수정란의 체외발육율에 영향을 미치지 않는 것으로 나타났다. 본 실험에서 생산된 배반포기 체외수정란의 세포수에는 커다란 차이가 인정되지 않았다.

• Korean Journal of Ecology and Environment
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• v.42 no.1
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• pp.19-25
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• 2009

The effects of artificial floating island on the changes in phytoplankton and zooplankton community structure were investigated monthly from September 2006 to May 2007 in Shingu reservoir. The total cell number of phytoplankton under the artificial floating island was three times less than those of control (without artificial floating island). The dominant species of phytoplankton were Lyngbya sp. on September, Cryptomonas sp. from October to January, Aulacoseira granulata on February and Oscillatoria sp. from March to May at lake water. Cyanophyta was dominated from February to March at lake water but it was dominated from March at artificial floating island area. The total individual number, species number of zooplankton and species diversity of phytoplankton and zooplankton under the artificial floating island were higher than those of lake water.

• Journal of Environmental Health Sciences
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• v.21 no.2
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• pp.27-35
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• 1995

In order to investigate acute toxicity and bioconcentration of heavy metals for a freshwater fish, the fish used in this experiment was goldfish, Carassius auratus. Each ten goldfish was accommonidated in a water and was treated with different concentration of Pb and Cu compound. The 24 $hr-LC_{50}$ was obtained by plotting on the log-normal distribution graph. Furthermore, the combined effect of Pb and Cu was also investigated the fish was treated with Pb or Cu compound only, and Pb and Cu compound together, respectively. These results were summarized as follows: 1. The 24 $hr-LC_{50}'s$ of Pb and Cu were 7.48 mg/l and 0.666 mg/l, respectively. 2. When single or/and combined treatment with Pb(7.0 mg/l) or/and Cu(0.6 mg/l) to Carassius auratus for 24 hours were performed, there was significant difference between the single or/and the combined treatment in their bioaccumulated Cu concentrations. Cu concentrations in goldfish were higher in the combined treatment than in the single treatment. 3. When Carassius auratus was exposed to 0.748 mg/l (1/10 of 24 $hr-LC_{50}$) and 1.496 mg/l of Pb (1/5 of 24 $hr-LC_{50}$) for 7 days, the bioconcentration factors (BCF) were 79.14 and 100.11 for Pb, respectively. The BCF of Pb was obtained as a linearity according to the concentration and exposure time as follows log BCF=1.014 log $P\cdot T$+1.011 ($r^2$=0.9041) where, P: pollutant concentration(mg/l) T: exposure time(day) 4. When Carassius auratus was pxposed to 0.0666 mg/l (1/10 of 24 $hr-LC_{50}$) and 0.1332 mg/l of Cu (1/5 of 24 $hr-LC_{50}$) for 7 days, the bioconcentration factors (BCF) were 55.42 and 63.24 for Cu respectively. The BCF of Cu was obtained as a linearity according to the concentration and exposure time as follows log BCF=0.571 log $P\cdot T$+1.823 ($r^2$=0.8974) where, P: polutant concentration(mg/l) T: exposure time(day)

• Journal of Korean Society of Environmental Engineers
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• v.35 no.7
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• pp.495-502
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• 2013

This work was performed to investigate proper condition of coagulation treatment as UF process pretreatment that consider UF permeate flux and residual Al concentration. The coagulant used an alum as $Al_2(SO_4)_3{\cdot}16H_2O$ and PACl (r = 1.5) made this study. The experiment was tested in adjusting conditions such as alum dose, flocculation time and coagulation pH of seawater. Consequently, higher coagulant dose lead to elevation of UF permeate flux while residual aluminium also increased in condition of pH 8.0. The most suitable condition which has a good permeate flux and low residual aluminium, in this works, was coagulant dose of 0.7 mg/L (as Al, alum) and 1.2 mg/L (as Al, PACl) and coagulation pH 6.5. In addition, applying the flocculation time with 1.2 mg/L of PACI reduced. The flocculation time reduced UF permeate flux in using alum.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.766-769
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• 2002

In this paper, we propose new orthogonal modulation method to enhance the performance of CCK adapted in 802.l1b WLAN. To maintain the orthogonality of codewords produced by CCK modulator, we devide 256 codewords into 8 subset by trellis coding and codewords On a subset are orthogonal each other. In result, this method restricts maximum data rate to 9.625Mbps, however, it is better about 1.5dB than original UK modulation at BER 10$^{-5}$ .

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.525-532
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• 2014

Since mine wastes were merely dumped in the mine waste dump, they have produced acid mine drainage (AMD). Therefore, main objective of this study was to evaluate the effect of coal combustion products (CCPs) on heavy metal stabilization and detoxification for mine wastes. Total six treatments for incubation test were conducted depending on mixing method (completely mixing and layered). Also, lysimeter experiment was conducted to examine efficiency of polyacrylamide (PAM) on reduction of mine wastes erosion. Result of incubation test showed that concentrations of soluble aluminium (Al) and iron (Fe) in leachate decreased compared to control. The lowest soluble Al and Fe in leachate was observed in 50% mixed treatment (14.2 and $1.03mg\;kg^{-1}$ for Al and Fe respectively) compared to control treatment (253.0 for Al and $52.6mg\;kg^{-1}$ for Fe). The pH of mine wastes (MW) and leachate increased compared to control after mixing with CCPs and ordered as control (MW 6.4, leachate 6.3) < 10% (MW 7.7, leachate 7.1) < 20% (MW 9.0, leachate 7.8) < 30% (MW 9.5, leachate 8.3) < 40% (MW 9.9, leachate 8.5) < 50% (MW 10.5, leachate 8.6). Application of PAM, both in liquid and granular type, dramatically decreased the suspended solid (SS) concentration of CCPs treatments. Reduction of SS loss was ordered as MW70CR30L ($24.4mg\;L^{-1}$) > MW70CR30LPL ($6.7mg\;L^{-1}$) > NT ($3.1mg\;L^{-1}$) > MW70CR30M ($1.6mg\;L^{-1}$) > MW70CR30MPL ($1.1mg\;L^{-1}$) > MW70CR30PGM ($0.7mg\;L^{-1}$) > MW70CR30LPG ($0.5mg\;L^{-1}$) > MW70CR30MPG ($0.4mg\;L^{-1}$). Overall, application of CCPs can be environmental friendly and cost-effective way to remediate coal mine wastes contaminated with heavy metals. In addition, use of PAM could help to prevent the erosion coal mine wastes in mine waste disposal area.