중.저준위 방사성 폐기물 처분부지의 지구화학 특성 I. 지하수

최병영,김건영,고용권,신선호,유시원,김두행,Choi, Byoung-Young,Kim, Geon-Young,Koh, Yong-Kwon,Shin, Seon-Ho,Yoo, Si-Won,Kim, Doo-Haeng 한국방사성폐기물학회 2008 방사성폐기물학회지 Vol.6 No.4

This study was carried out to identify the characteristics of hydrochemistry controlling groundwater chemical condition in a repository site of Gyeongju. For this study, 12 bore holes of all monitoring bore holes in the study area were selected and total 46 groundwater samples were collected with depth. In addition, 3 surfacewater samples and 1 seawater sample were collected. For water samples, cations and anions were analyzed. The environmental isotopes(${\delta}^{18}O-{\delta}D$, Tritium, ${\delta}^{13}C,\;{\cdot}{\delta}^{34}S$) were also analyzed to trace the origin of water and solutes. The result of ${\delta}^{18}O\;and\;{\delta}D$ analysis showed that surface water and groundwater were originated from precipitation. Tritium concentrations of groundwater decreased with depth but high concentrations of tritium indicated that groundwater was recharged recently. The results of ion and correlation analysis showed that groundwater types of the study area were represented by Ca-Na-$HCO_3$ and Na-Cl-$SO_4$, which was caused by sea spray and water-rock interaction. Especially, high ratio of Na content in groundwater resulted from ion exchange. For redox condition of groundwater, the values of DO and Eh decreased with depth, which indicated that reducing condition was formed in deeper groundwater. In addtion, high concentration of Fe and Mn showed that redox condition of groundwater was controlled by the reduction of Fe and Mn oxides.

[수필] 새 달력을 걸며

최병영 고시계사 2017 考試界 Vol.63 No.1

低炭素 dual Phase 鋼의 마르텐사이트 組織과 機械的 性質에 關한 硏究

崔秉泳 전북대학교 공업기술연구소 1982 工學硏究 Vol.12 No.-

A study has been made on the effect of martensite volume fraction, martensite morphology on the mechanical properties of low carbon dual phase steel(AISI 1020). In order to obtain both high strength and good formability, the following heat treatment were applied ; intermediate quenching, intercritical annealing and step quenching under the condition of various intercritical temperature. Experimental results showed as follows ; 1. Martensite volume fraction was increased in linear proportions with inercritical temperatures. 2. The yield and tensile strength were increased in linear with increasing martensite volume fraction. 3. In case of intermediate quenching, the value of σ_Y․S σ_U․T․S ration was the lowest and showed the largest elongation. These results showed good formability due to fine martensite morphology and discontinuous distribution of martensite particles in the ferrite matrix.

Spatio-temporal variation of pH and ionic concentrations in precipitation: interaction between two contrasting stationary sources affecting air quality

최병영,윤성택,Gyu-Il Yeom,김기현,김경호,Yong-Kwon Koh 한국지질과학협의회 2008 Geosciences Journal Vol.12 No.3

Meteorological and geological factors affecting the pH and ionic concentrations of precipitation were investigated from Jecheon City, Korea. The air quality of the study area is affected by two contrasting stationary sources: 1) a coal-fired power plant to the east-northeast and 2) limestone quarries and cement-manufacturing factories to the east to south-southeast of Jecheon. The temporal change of rainwater chemistry is affected by the interaction between acidic gases and alkaline substances from the above two sources. Accordingly, rainwater pH at a city center widely varies from 4.9 to 8.3. Acidic gases from the power plant are likely to acidify the rainwater pH. As the prevailing wind direction during rainfall events shifted to ENE–SSE, rainwater pH at the city center rapidly increased to >6.5 (up to 7.8). Concomitantly, ionic concentrations (esp., Ca, K, and Na) increased sharply, especially when winds are brown from SE, probably due to major influences of particles coming from limestone quarries. The enrichment factor analyses of acidity and cations also indicate that the acidic components in precipitation are mostly neutralized by limestone particles. In addition, rainwater chemistry showed a spatial variation as a function of the direction and distance from the above two sources. Our results demonstrate a good example of competing roles between the anthropogenic acidic source and the geologic alkaline source.

고주파 유도경화처리한 중탄소강의 회전접촉 피로거동에 미치는 탄소함량의 영향

최병영,이동민,Choe, Byeong-Yeong,Lee, Dong-Min 한국재료학회 1997 한국재료학회지 Vol.7 No.9

본 연구에서는 고주파 유도경화처리한 중탄소강의 회전접촉 피로거동을 0.44wt.%C강과 0.55wt.%C강을 사용하여 조사하였다. 회전접촉 피로시험은 Polymet RCF-1 시험기에서 탄성유체 윤활 조건으로 회전속도 8,000rpm, 최대 Hertz응력 492kg/m$m^2$을 가하면서 실시하였다. 미세한 lath마르텐사이트가 고주파 유도경화한 0.44wt.%C강과 0.55wt.%C강의 표면경화층에 형성되었고 소량의 페라이트가 일부 형성되었으며 0.44wt.%C강과 0.55wt.%C에 비해 비교적 큰 페라이트가 나타났다. 회전접촉 피로시험 후 표면경도가 거의 유지되는 표면경화층에서 회전접촉 피로시험전에 비해 경도가 상승하였다. 이 경도증가량의 최대치($\Delta$ Hv$_{max}$)와 피로수명과의 관계를 조사한 결과 0.55wt.%C강이 0.44wt.%C강에 비해 회전접촉 피로중에 일어나는 소변형에 대한 높은 저항성에 주로 기인하여 $\Delta$ Hv$_{max}$값은 낮게 나타나고 피로수명은 높게 나타났다.

구조체 콘크리트의 강도 발현성에 관한 연구

최병영 中央大學校 建設大學院 1994 建設論叢 Vol.7 No.1

반응성용질이동 모델링을 이용한 장기간의 콘크리트 변질과정과 우라늄의 용해도에 대한 개념 모델링

최병영,고용건,김건영,유시원,안상원,배대석,Choi, Byoung-Young,Koh, Yong-Kwon,Kim, Geon-Young,Yoo, Si-Won,An, Sang-Won,Bae, Dae-Seok 한국방사성폐기물학회 2008 방사성폐기물학회지 Vol.6 No.1

Long-term degradation of coment barrier by diffusion was studied with reactive transport modeling. The result of modeling showed that cement barrier was altered about 30cm thickness after 50,000 years. The pH decreased from 13.0 to 11.9 because of depletion of alkali ions, and dissolution/precipitation of portlandite and CSH (Calcium Silicate Hydrate). In addition, porosity increased about 0.3 because of dissolution of portlandite and $CSH2.0(Ca_2SiO_3(OH)_2:0.17H_2O)$. The solubility of uranium also increased with the increase of pe value The results of this study indicate that long-term degradation of comet can enhance the transport of nuclide by changing pH, pe, porosity in barrier.

한국인 골반뼈의 성별판별을 위한 군집분석

최병영 관동대학교 의과학연구소 2000 關東醫大學術誌 Vol.4 No.1

Pelvic bone is the major bone which has the quite different features between male and female. And these features are well described in almost all gross anatomy textbooks. The parameters which are used to sex determination are related with those of obstetrics. To suggest the most significant parameters for sex discrimination with the bones, we have selected the frequently mentioned 21 metric fields of non-pathologic Korean pelvic bones, whose sexes were already confirmed (M:40, F:19). For easuring these metric parameters, the statistic procedures (descriptive statistics and discriminant analysis, group analysis) were performed(SAS PC version 6.11). The parameters showing more than 80% of discriminating probability are the acetabular length(Martin No. 22) and the pubic angle (Martin No. 16). The parameters showing more than 75% of discriminating probability are the transverse diameters of pelvic outlet (Martin No.27), the breadth of greater sciatic notch, the ischial length (Martin No. 15a), the pelvic breadth (Martin No. 2), the obturator foramen long length (Martin No. 20), the obturator foramen short length (Martin No. 20), and the pelvic height (Martin No.1). All the metric parameters, it could be categorized into 5 groups.

2 상조직강의 항복 및 변형거동에 미치는 퍼얼라이트의 영향

최병영,오상엽 대한금속재료학회(대한금속학회) 1987 대한금속·재료학회지 Vol.25 No.9

The dual phase steels of ferrite-martensite and ferrite-martensite-pearlite were prepared by two step cooling or isothermal holding after intercritical annealing. And this research investigated the effect of pearlite on the yielding and deformation behavior of these dual phase steels. It was observed that second phase particles with pearlite-martesite interfaces were distributed in the ferrite matrix. The structure of pearlite-martensite interface was also observed by using SEM. Continuous or discontinuous yielding apeared in the specimens of ferrite-martensite-pearlite. The lower yielding ratio and continuous yielding were shown in the specimens with more martensite content (≥5.8 vol%). The microstructure observed by TEM showed that the mobile dislocations causing continuous yielding and the pinned dislocations by solute atoms were distributed in the ferrite. The effect of pearlite on the variation of work hardening exponents during tensile deformation was also discussed in terms of the Modified Crussard-Jaoul analysis.

지구화학 모델을 이용한 장기간의 강알칼리성 지하수-암석의 반응 개념 모델링

최병영,류시원,장광수,김건영,고용권,최종원,Choi, Byoung-Young,Yoo, Si-Won,Chang, Kwang-Soo,Kim, Geon-Young,Koh, Yong-Kwon,Choi, Jong-Won 한국방사성폐기물학회 2007 방사성폐기물학회지 Vol.5 No.4

본 연구에서는 핵폐기물 매립장의 인공 방벽으로 사용되는 시멘트 물질들과 주변 지하수 반응 결과로 형성되는 강알칼리성 지하수와 주변 암과의 반응을 통해 변화되는 지하수 특성을 지구화학 모델링을 통해 예측하고자 하였다. 연구 결과 시멘트 수화반응을 통해서 pH는 13.3를 나타내었으며 이때 생성되는 광물들은 Brucite, Katoite, Calcium Silicate Hydrate(CSH 1.1), Ettringite, Hematitie, Portlandite였다. 이들 광물들과 경주 지역에서 채취된 지하수의 반응 모델링에서는 지하수의 pH가 12.4로 예측되었다. 이러한 강알칼리성 지하수와 주변 화강암과의 반응은 $10^3$ 년 동안 반응속도 모델링을 통해 모사하였다. 그 결과 지하수의 최종 pH는 11.2였으며 pH는 규산염 광물과 CSH 광물들의 용해 침전에 의해 조절되고 있었다. 또한 지하수 수질도 이들 광물들과 점토광물 및 산화광물들의 용해 침전에 의해 결정되고 있었다. 본 연구 결과는 장기간 동안의 강알칼리성 지하수와 주변 암과의 반응 모델링을 통해 지구화학 및 수질 변화를 예측함으로서 인공 방벽의 안정성 평가에 기여할 수 있을 것으로 판단된다.