• Journal of the Mineralogical Society of Korea
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• v.24 no.2
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• pp.91-99
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• 2011

The turbidity in several wells of Samdong-myeon, Ulsan, exceeded potable groundwater standard (1 NTU). Mineralogical analysis showed that the fine suspended particles are ferrihydrite spheres with a size of less than $0.5\;{\mu}m$ and helical iron-oxidizing bacterial filaments, and their aggregates. Ferrihydrite was almost amorphous only showing two electron diffraction rings, and contained Si and P. Helical bacterial filaments were almost replaced by ferrihydrite. The helical bacteria have played an important role in the ferrihydrite formation by becoming the loci for ferrihydrite precipitation as well as oxidizing ferrous iron. The physicochemical conditions of low pH, low redox potential, high Ca concentration, and high alkalinity are consistent with the hydrogeochemical characteristics of carbonate groundwater, implicating that the inflow of deep ferriferous carbonate groundwater and its oxidation have caused the ferrihydrite turbidity in several wells of the study area.

• Journal of the Microelectronics and Packaging Society
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• v.26 no.2
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• pp.1-8
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• 2019

The demand and importance of adhesives and paint coatings applied to solid surfaces such as metals, ceramics, and plastics are increasing. In this study, the influencing factors on the adhesive strength between the polymer coating and the metal adherend were investigated by Dolly test when the adhesive or the paint coating was applied on the metal adherend. Two-component epoxy adhesive was used as the adhesive, and EH2350, a two-component epoxy paint for anti-corrosion, was used as the paint. Especially, the effect of adherend metals(Al, Fe, STS, Cu, Zn), surface roughness and surface contamination(tap water, salt water) on adhesive strength was studied as influencing factors. The adhesive strength between adhesive and adherend was different when the type of metal adherend was different even when the same adhesive was used. It was found that spray water cleaning was necessary before the paint coating process on the surface of the oxide contaminated adherend with tap water or salt water. As a result of this study, it was confirmed that Dolly test can be widely used in the future to measure adhesive strength between paint coating and adherend.

• The Journal of Internal Korean Medicine
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• v.25 no.1
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• pp.138-148
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• 2004

Objective : Insomnia is the disorder of initiation or maintenance in sleeping that results in daytime sleepiness and dysfunction, and it arises from multiple psychological, physiological and environmental factors. A number of stroke patients suffer from insomnia are classified as sleep disorder patients with physical illness. In addition, insomnia may have profound deleterious effects on the natural course of stroke. We are to assess the effectiveness of intradermal acupucture on stroke combined with insomnia. Methods : We recruited hospitalized patients with insomnia after stroke. Then, the subjects were allocated into a treatment group and a control group by randomization. The treatment group received intradermal acupuncture therapy at He-7(神門), EH-6(內關) correctly. However in control group, intradermal acupuncture were just attached to He-7(神門), EH-6(內關) without insertion. Treatment over time at first day and second day a various indexes were repeatedly checked such as sleep latency, total sleep time, sleep quality, condition on awakening, ability of concentration, morning sleepiness, Insomnia Severity Index, and Athens Insomnia Scale. In the second analysis, we divided the treatment group into a response and a non-response group by their response to intradermal acupuncture. With the acupuncture treatment, accompanied symptoms were checked Results : Among thirty two subjects, two of them were dropped out: One complained the pain from needle insertion, and the other underwent the change of his herbal medication. At baseline investigation with the residual 30 subjects, the control and the treatment group were assessed to have an equal comparability. In the treatment group, sleep latency, total sleeping time, a number of awakenings, sleep quality and ability of concentration showed improvement significantly compared with the control group. The non-response Group showed symptoms such as nausea and halitosis, belching and acid regurgitation, abundant expectoration, while Responder Group showed palpitation, oppressed feelings in chest and sleep disorder. Conclusions: The result of this clinical study suggests that the intradermal acupuncture at He-7(神門), EH-6(內關) is one of the effective treatments for the insomnia after stroke.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.166-173
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• 2006

This research has been performed to clarify the relationship between hydrogeochemistry and bacterial community structure in groundwater contaminated with landfill leachate. We collected and analyzed samples from 5 sites such as leachate (KSG1-12), treated leachate (KSG1-16), two contaminated groundwaters (KSG1-07 and KSG1-08) and non-contaminated groundwater (KSG1-13). pH was 8.83, 8.04, 6.87, 6.87 and 6.53 in order; redox potential (Eh) 108, 202, 47, 200 and 154 mV; electric conductivity (EC) 3710, 894, 1223, 559 and 169.9 $\mu$S/cm; suspended solids (SS) 86.45, 13.74, 4.18, 0.24 and 11.91 mg/L. In KSG01-12, the ion concentrations were higher especially in $Cl^-$ and $HCO_3^-$ than other sites. The concentrations of Fe, Mn and $SO_4^{2-}$ were higher In KSG1-07 than in KSG1-08, and vise versa in $NO_3^{2-}$. In the comparison of DGGE fingerprint patterns, the similarity was highest between KSG1-13 and KSG1-16 (57.2%), probably due to common properties like low or none contaminant concentrations. Otherwise KSG1-08 showed lowest similarities with KSG1-13 (25.8%) and KSG1-12 (27.6%), maybe because of the degree of contamination. The most dominant bacterial species in each site were involved in $\alpha$-Proteobacteria (55.6%) in KSG1-12, $\gamma$-Proteobacteria (50.0%) in KSG1-16, $\beta$-Proteobacteria (66.7%) in KSG1-07, $\gamma$-Proteobacteria (54.5%) in KSG1-08 and $\beta$-Proteobacteria (36.4%) in KSG1-13. These results indicate that the microbial community structure might be changed according to the flow of leachate in grounderwater, implying changes in concentrations of pollutants, available electron accepters and/or other environmental conditions.

• Macromolecular Research
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• v.17 no.4
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• pp.240-244
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• 2009

High molecular weight(MW), 3-arm star poly(methyl methacrylate)(PMMA) with a narrow MW distribution($M_n$=570,000 g/mol, PDI=1.36) was successfully synthesized by activators regenerated by electron transfer(ARGET) atom transfer radical polymerization(ATRP). The polymerization was carried out with a trifunctional initiator/$CuBr_2$/N,N,N',N",N"-pentamethyldiethy lenetriamine(PMDETA) initiator/catalyst system in the presence of a tin(II) 2-ethylhexanoate [$Sn(EH)_2$] reducing agent at $90^{\circ}C$. The concentration of the copper catalyst was as low as 30 ppm, and a high initiation efficiency of the initiating sites was obtained. The chain-end functionality of the high MW, 3-arm star PMMA was confirmed by a chain extension experiment with styrene via ARGET ATRP, using the same catalyst system.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.129-130
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• 2008

교감 신경계의 활성정도를 판별할 수 있는 지표로 피부저항(Galvanic skin resistance: GSR)이 있다. 교감신경이 흥분하면 땀이 분비되어 손가락의 피부저항이 감소하게 된다[1]. 전자기장에 민감한 사람(electromagnetic hypersensitivity: EHS)에게 전자기장을 노출시키면 전자기장을 잘 느끼지 못하는 일반인에 비해 교감신경이 많이 흥분하여 땀을 더 많이 분비할 것이라 생각하여 손가락 피부저항의 변화를 측정하여 전자기장에 민감한 사람과 일반인의 교감신경 활성정도의 차이를 알아보고자 하였다. 그러나 전자기장에 민감한지 민감하지 않은지를 판별하기 위한 인지 및 증상에 관한 설문에 의해서도 피부저항의 변화가 생길 수 있다. 따라서 본 연구에서 전자파에 민감한 사람과 일반인간의 언어자극에 의한 피부저항의 변화를 알아보고 전자기장 노출 실험에서 인지 설문이 전자기장 노출여부에 의한 피부저항의 변화에 영향을 주는지 주지 않는지를 알아보고자 한다. 피부저항 측정 결과 EHS와 일반인군 모두에게서 언어자극(인지 및 자각증상에 관한 설문)에 의해 피부저항이 감소되는 경향을 보였다.

• Journal of Acupuncture Research
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• v.23 no.1
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• pp.179-186
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• 2006

Background : Recently the demand was increasing on the data describing treatment rates and the outcome of Androgenetic Alopecia using Oriental Medicine. Thus this study was designed to observe androgenetic Alopecia treatment using Oriental Medicine including acupuncture and herb because there has been no such statistics. Objectives : Our purpose was determine whether oriental medicine treatment leads to clinical improvement in men with androgenetic alopecia. Methods : Eighty two Men, 17 to 53 years of age, with male pattern hair loss according to a modified Norwood/Hamilton classification scale(II to VI) were enrolled in this study. Patients were treated with multidisciplinary Korean oriental medicine treatment (herbal acupuncture, acupuncture, herb, chuna therapy) at twice a week for 6 months to 12 months. Efficacy was evaluated by patient and investigator assessment, and global photographic review. Results : Oriental medicine treatment improved scalp hair by all evaluation. Patient self assessment demonstrated that Oriental medicine treatment slowed hair loss, increased hair growth, and improvement appearance of hair. These improvements were corroborated by investigator assessments and assessments of photographs. Conclusion : Oriental medicine treatment has significant effects on the androgenetic alopecia. Longer follow up studies are needed to examine whether its effects last long enough for the patients with androgenetic alopecia.

• Progress in Superconductivity and Cryogenics
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• v.4 no.2
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• pp.73-77
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• 2002

In order to derive the detailed design of Thermal Shield Cryopanel. which plays a role to make the Tokamak Nuclear Fusion Equipment work at both static and efficient conditions the commercially available software package FLUENT Version 5.3, was utilized. This study investigated the effects of thermal sources and distributions on the temperatures of Lid. Body. Base. and EH-Port Cryopanel by the numerical technique whose grid generations cover the solid and 9as region of the panel. The physical model of the Thermal Shield Cryopanel is that the 10mm diameter of the pipe with 1mm thickness is soldered on the Stainless steel Panel with 4mm thickness. The heat fluxes to the panel are assumed to be by thermal radiation in the vacuum space and by conduction through the supporters. The inlet conditions of Helium gas are 20 atmospheric Pressures and 60K temperature. The panel shapes with cooling Pipes and the operational conditions to keep appropriate temperature distribution of Thermal Shield Cryopanel Have been found and suggested.

• Journal of Environmental Impact Assessment
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• v.12 no.1
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• pp.9-22
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• 2003

To consider environmental characteristics in the scope of geochemistry of streams, Hwasun area, soil, sediment and water samples near/in the streams were analyzed in texture and metal contents of soil and sediment and in quality in water. From those analyses, the soils are loamy sand, sandy loam, loam and silty loam in texture. And, the sediments are slightly gravelly sand, gravelly sand and gravelly muddy sand in facies. Metal contents in soils and sediments are of high near Hwasuneup and Hwasun coalfield. In peculiar, P, Co, Li, Ni, Zn and Pb exceed over crust mean contents. Physico-chemistry of above streams according to pH-Eh and Piper's diagrams indicates that the streams are, typically, assigned to natural river water. Water qualities of BOD, T-N and T-P in areas near Hwasun coalfield, Dongmyeon and Hwasuneup are polluted over V level. Enrichment factor(EF) representing metal condensation in P, Cu, Zn and Pb appear near Hwasun coalfield and Hwasuneup from the soil and sediment samples, in part. Additionally, river water in dry season is very high in BOD, T-N, $Na^+$ and ${SO_4}^{2-}$. It is suggested that the relatively high metal contents in the stream be connected with above coalfield and urban areas.

• Nuclear Engineering and Technology
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• v.55 no.4
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• pp.1439-1447
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• 2023

The fuel cycle characteristics of the IVG.1M reactor were studied within the framework of the research reactor conversion program to modernize the IVG.1M reactor. Optimum use of the nuclear fuel and reactor was achieved through routine methods which included partial fuel reloading combined with scheduled maintenance operations. Since, the additional problem in planning the fuel cycle of the IVG.1M reactor was the poisoning of the beryllium parts of the core, reflector, and control system. An assessment of the residual power and composition of spent fuel is necessary for the selection and justification of the technology for its subsequent management. Computational studies were performed using the MCNP6.1 program and the neutronics model of the IVG.1M reactor. The proposed scheme of annual partial fuel reloading allows for maintaining a high reactor reactivity margin, stabilizing it within 2-4 β_eff for 20 years, and achieving a burnup of 9.9-10.8 MW × day/kg U in the steady state mode of fuel reloading. Spent fuel immediately after unloading from the reactor can be placed in a transport packaging cask for shipping or safely stored in dry storage at the research reactor site.