• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.151-151
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• 2003

토양에 방치된 농업용 폐비닐은 거의 분해가 되지 않으며, 수분과 공기의 유통을 차단하고 토양 내 미생물들의 흐름을 막아 토양을 더욱 황폐화시키게 된다. 불법적인 소각 때는 산불의 위험에다 다이옥신, 염소 및 염화수소가스 등을 배출해 대기오염을 유발시킨다. 폐비닐을 열분해과정으로 처리하여 아주 작은 입자로 미분쇄하고 겔상태로 용융된 원료물질속으로 완전히 균일하게 혼합하여 골재로 활용하는 과정에서 가스상과 액상의 여러 가지 중간생성물질이 발생하게 되며, 농약의 살포에 의한 잔류농약 둥 인체에 유해가능한 요소들이 있을 수 있다. 본 연구에서는 개발공정이나 제품에서 인체에 영향을 미칠 수 있는 물질에 대하여 유해성을 평가하고 용응 겔 및 가스와 오일에 함유된 화학성분을 분석하였기에 보고하고자 한다 시험동물의 혈액생화학적 검사에서는 농업용 폐비닐물질 및 열분해 파생물질의 혈청 Cholesterol, 혈청 Alanine aminotranseferse와 Aspartate aminotransferse, Albumin 수치, LDH, Glucose, Uric acid, A/C 비 등의 생화학적 활성도를 측정한 결과들에서는 농업용 폐비닐물질을 투여한 시험군에서 나타난 결과와 비교하여 열분해 파생물질을 투여한 시험군에서 나타난 결과가 감소된 통계결과를 보였다. 이 결과들은 농업용 폐비닐물질을 투여한 시험군보다 열분해 파생물질을 투여한 시험군의 외부독성물질 투여에 의한 생체독성의 영향과 생체에 가해진 스트레스강도가 작았음을 의미하는 것이다. 잔류농약분석에서는 시료로부터 농약을 추출하는 용매추출과정, 시료추출물 중 공존하는 방해성분을 제거하는 정제과정, 폐비닐물질 및 열분해 파생물질 성분을 100mg/kg 이상군의 투여 후 시험동물의 부검시 모든 투여군에서 독성소견이 인정되지 않았다. 이와 같은 결과로 열분해 및 연소과정에서 발생하는 파생물질의 분석결과를 응용하여 대기오염을 방지하고 인체 유해물질을 차단하는 공해 방지 설계의 기초자료를 제안하고자 한다.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.2
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• pp.103-108
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• 2014

Using dried sludge as a secondary fuel of a coal-fired power plant is proposed as an alternative option for sludge disposal. Because elemental contents of sludge are different from those of coal, different levels of acidic gas emissions are expected from the co-combustion of sludge with coal. In this study, sludge samples were obtained from 7 sewage treatment plants in Korea. Each sludge sample was combusted together with coal in a lab-scale combustor, and the concentrations of nitrogen oxides ($NO_x$), sulfur dioxide ($SO_2$), hydrogen chloride (HCl), chlorine ($Cl_2$) in the flue gas were analyzed. Compared to the combustion of coal only, $NO_x$ concentration was slightly higher in the flue gas from the co-combustion of coal and sludge. $SO_2$ emission increased with the combustion of sludge due to the higher content of sulfur in sludge than in coal. For most of the tested samples, the concentrations of HCl and $Cl_2$ were varied depending on the chlorine content in the sludge sample.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.12
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• pp.967-972
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• 2013

A MILD (Moderate and Intense Low oxygen Dilution) combustion, which is effective in the reduction of NOx, is considerably affected by the recirculation flow rate of hot exhaust gas to the combustion furnace. The present study used the MILD combustor, which has coaxial cylindrical tube. The outside tube of the MILD combustor corresponds to the exhaust gas passage and the inner side tube is the furnace passage. A numerical analysis was accomplished to elucidate the characteristics of exhaust gas entrainment toward the inner furnace with the changes of coanda nozzle geometrical parameters, nozzle passage gap length, nozzle passage length, nozzle angle and expansion length. The optimal configuration of coanda nozzle for the best entrainment flow rate was gap length, 0.5 mm, expansion angle, 4o and expansion length, 146 mm. The nozzle passage length was irrelevant to the exhaust gas entrainement.

• Economic and Environmental Geology
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• v.37 no.5
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• pp.437-457
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• 2004

The geology of the Kualakulun in the Middle Kalimantan, Indonesia comprises Permian to Carboniferous Pinoh Metamorphic Rocks and Cretaceous Sepauk Plutonics of the Sunda Shield, late Eocene Tanjung Formation, Oligocene Malasan Volcanics, Oligocene to early Miocene Sintang Intrusives and Quaternary alluvium. Tanjung Formation was deposited in low-and high-sinuosity channel networks developed on the proximal to distal delta plain and delta front forming southward paleoflow system, which, in turn, gradually change into shallow marine environment. Four main deformational phases are recognized: D1, folding of metamorphic rocks accompanied by development of S1 schistosity under regional metamorphic condition; D2, ductile shearing in Cretaceous granitoids; D3, folding of metamorphic rocks accompanied by S2 crenulation cleavage; D4, faulting under N-S compressional regime during Tertiary times, producing NE-trending sinistral and NW-trending dextral strike-slip faults and N-S to NNE-trending normal faults.

• Communications for Statistical Applications and Methods
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• v.18 no.6
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• pp.675-685
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• 2011

This paper proposes a job matching function that calculates the job matching probability of a job-seeker to an employer taking the working conditions of a job-seeker and an employer into account. In addition, this study analysis the degree of centrality that means interactions of a job-seeker and an employer utilizing social network analysis. The results are follows. First, a degree of centrality is found to be severely concentrated in certain job-seekers or certain employers; in addition, there are many job-seekers and employers who have no matching results. Second, according to decision tree analysis, characteristics of a job-seeker that influences the degree of centrality are gender, age and degree of education in order of importance. The characteristics of a employer that influences the degree of centrality are proposed salary, industry classification and firm size in order of importance.

• Journal of Korean Society of Steel Construction
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• v.20 no.6
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• pp.793-805
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• 2008

Recently, steel modular systems are developed and have been applied to the projects requiring fast construction such as military barracks and vertical expansion of school buildings. The existing modular system with standard module of ${6m\times3m}$ has a problem that many columns are duplicated in the module connection and the wall thickness increases. In this study, $12m{\times}3m$ module is proposed to solve this problem. Various types of beam-middle column connection which are essential for realizing the $12m{\times}3m$ module are proposed and their maximum load capacity and failure mode are analytically and experimentally evaluated. The comparison between analytical and experimental results shows that the maximum axial load and failure mode can be accurately estimated by finite element analysis. Some connection types which have higher failure load than the design load of the column, can be used as the beam-middle column connection detail of the $12m{\times}3m$ module.

• The Journal of Internal Korean Medicine
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• v.27 no.2
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• pp.295-304
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• 2006

Objectives : This study was done to investigate whether two oriental prescriptions, saganmahwang-tang (SMT) and prescription C (P-C) significantly affect mucin release from cultured hamster tracheal surface epithelial (HTSE) cells. Methods : Cofluent HTSE cells were metabolically radiolabeled with 3H-glucosamine for 24 hrs and chased for 30 min in the presence of SMT or P-C to assess the effect of each agent on 3H-mucin release. Possible cytotoxicities of each agent were assessed by measuring lactate dehydrogenase (LDH) release. Also, the effects of SMT and P-C on contractility of isolated tracheal smooth muscle were investigated. Results : SMT significantly inhibited mucin release from cultured HTSE cells, without cytotoxicity. P-C significantly increased mucin release from cultured HTSE cells, with significant cytotoxicity. SMT inhibited Ach-induced contraction of isolated tracheal smooth muscle. P-C did not affect Ach-induced contraction of isolated tracheal smooth muscle. Conclusion : Results su99est that SMT and P-C have regulating effects on mucin secretion from airway goblet cells. Further investigation is needed, because of the value in finding novel agents to this purpose, and these oriental medical prescription have potential for such a role.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.723-733
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• 2009

The purpose of this study is to evaluate the difference about pathogenesis of normal group and depression group(who' pulmonary function is below expected value). Author used DSOM to investigate oriental pathogenesis. Depression group is consisted of people who's FVC%(forced vital capacity)is below 80% or $FEV_1$/FVC%(Forced Expiratory Volume in 1sec/FVC) is below 70%, and they don't have history of lung disease(Athma, tuberculosis, COPD, suchlike). Normal group is consisted of people who's FVC%(Forced Vital Capacity) is in 80-120% and $FEV_1$/FVC%(Forced Expiratory Volume in 1sec/FVC) is above 70%. they also don't have history of lung disease. Author carried out each group's PFT(pulmonary function test) by ATS(American Thoracic Society) method. DSOM was used for oriental pathogenesis investigation of two groups. There was significant difference between normal group and depression group in Kidney(p<0.05). In depression group comparison of sex, there was significant difference between male and female in stagnation of qi, cold, heat, spleen, phlegm(p<0.05). In Normal group there was significant difference between male and female in stagnation of qi, blood stasis, cold, heat, spleen(p<0.05). In depression group comparison of smoke, there was no significant difference between smoker and non-smoker(p<0.05). In Normal group comparison of smoke, there was significant difference between smoker and non-smoker in heat(p<0.05). This result showed difference of the pathogenesis between Depression group and Normal group.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.3
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• pp.600-606
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• 2008

The purpose of this study was to investigate Anti-allergic Inflammatory Effects of Hwangyounhaedog-tang on PMA plus A23187-stimulated RBL-2H3 cells. We examined MTT assay, ${\beta}$-hexosaminidase activity, IL-4 and TNF-${\alpha}$ from RBL-2H3 after pre-treatment with HHT. In addition, we investigated expression of COX-1 and COX-2 mRNA using RT-PCR study. The results are as follows: All the concentrations of HHT from 1 to 4 mg/ml didn't have an effect on cell viability. In RBL-2H3 cells, ${\beta}$-hexosaminidase release, IL-4 and TNF-${\alpha}$ were significantly reduced by treated all concentrations of HHT. COX-2 on mRNA expression was reduced at treatment 2mg of HHT prior to stimulating by A23187. These results indicate that HHT has inhibition effects on allergy in this study.

• Biomolecules & Therapeutics
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• v.10 no.3
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• pp.193-199
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• 2002

The arylamine N-acetyltransferases (NATs) are a family of enzymes that N-acetylate mylhydrazines and arylamines through transfer of an acetyl group from acetyl coenzyme A. This activity was found to vary among individuals as a Mendalian trait and the basis of the genetic differences in human NAT activity is one of the best of the genetic studied examples of pharmacogenetic variation. The classical N-acetylation polymorphism is regulated at the NAT2 locus, which segregates individuals into rapid, intermediate, and slow acetylator phenotypes. In this study, the relationship between NAT2 activity phenotype using HPLC:UV assay for the determination of dapsone and monoacetyldapsone in plasma and NAT2 genotype by PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) was investigated in the F2 hybrid (Fischer 344 vs Wistar-Kyoto) rats. Three Common mutant alleles at the NAT2 gene locus have been identified in the F2 generation progeny of Fischer 344 rats as raid acetylator and Wistar-Kyoto rats as slow acetylator segregated into three modes (low, intermediates, and high) with simple Mendelian inheritance. The metabolic activity of NAT2 of the intermediate and rapid acetylators is significant1y greater than slow acetylator, but the metabolic activity of rapid acetylator is not significantly different from Intermediate type. Therefore, we could observe that complete trimodal NAT2 genotypic alleles and incomplete trimodal NAT2 metabolic phenotypic distribution in tile F2 hybrid rats. These observations suggest that the relationships between NAT2 genotype and metabolic phenotype exists and F2 hybrid (Fischer 344: Wistar-Kyoto) animal models about NAT2 polymorphism might be applied in the toxicity and pharmacogenetic studies of arylamine drugs and carcinogens.