• Proceedings of the Korean Nuclear Society Conference
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• 1995.05b
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• pp.775-780
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• 1995

방사성폐기물 처분장 폐쇄후 처분시설의 성능평가를 수행하기 위해 해안에 위치한 임의의 지역을 가정하여 평가하여 보았다. 성능평가를 위해 영국 AEA Technology가 개발한 확률론적 종합 성능평가 코드인 MASCOT을 이용하였다. 임해지역에 위치한 가상 처분장에 대해 MASCOT을 이용하여 계산하여 본 결과 생태계에서 개인이 받게되는 예상 최대 위험확률은 폐쇄후 4,000년에 9.45$\times$$10^{-7}$yr$^{-1}$로서 이는 성능목표치를 만족할 수 있음을 알 수 있었다. 가상 처분장에 대해 성능평가를 수행함으로써 향후 방사성폐기물 처분부지가 결정되었을 경우, 결정된 처분부지의 특성에 따른 성능평가 및 환경영향평가를 원활히 수행할 수 있을 것이다.

• Elastomers and Composites
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• v.35 no.1
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• pp.12-18
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• 2000

With growing concerns of environment and due to strengthening the government regulations on volatile organic compounds(VOC) the coatings industries are developing new technologies to reduce the amount of VOC released from coatings. In this study. a water soluble curing agent of amino-epoxy adduct was synthesized and its structure was identified by FT-IR, GPC and TG/DTA. The mechanical properties of the new curing agent in combination of KER-828 and KER-500 were investigated respectively. As an experimental result, the drying time of KER-828 was faster than that of KER-500 but the adhesion and impact strength of KER-500 was better than that of KER-828.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.349-354
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• 2015

The AMMI (additive main effects and multiplicative interaction) and GGE (genotype main effect and genotype by environment interaction) biplot which were accounted for a substantial part of total sum of square in the analysis of variance suggested to be more appropriate models for explaining G $\times$ E interaction. The grain yield of total ten sesame genotypes was significantly affected by environment which explained 61% of total variation, whereas genotype and genotype x environment interaction (G $\times$ E) were explained 16%, 24% respectively. From the results of experiment, three genotypes Miryang49, Koppoom and Ansan were unstable, whereas other three genotypes Kyeongbuk18, Miryang50 and Kanghuk which were shorter projections to AEA ordinate were relatively stable over the environments. Yangbak which was closeness to the mean yield and short projection of the genotype marker lines was regarded as genotype indicating good performance with stability. Ansan, Miryang48 and Yangbaek showed the best performance in the environments of Naju, Suwon, Iksan and Andong. Similarly, genotype Miyrang47 exhibited the best performance in the environments of Chuncheon and Miryang. Andong is the closest to the ideal environment, and therefore, is the most desirable among eight environments.

• The Korean Journal of Ecology
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• v.13 no.3
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• pp.165-172
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• 1990

The contents of Pb and Cd in litters of Ginko biloba collected from thirty-four areas in Seoul were measured and analyzed for among relative air pollutions. S contents in litters of G. biloba were 0.88% at Hyehwadong, 0.98% at Yongsan and 0.95% at Ch angdong. Mean value were 0.65% in 0-10 km areas from Kwanghwamun, but were 0.47% in 10-15 km areas. In S contents, the correlation between 0-5 km area and 10-15 km area from Kwanghwamun was high significant, but correlation between 0-5 km area and 5-10 km area from Kwanghwamun had no significance. Pb contents were 118.95 ppm at Pildong, 112.22 ppm at Ulchiro 3-ga and 105.55 ppm at Bus terminal (Banpo). In Pb contents the correlation between 0-5 km area and 10-15 km aea from kwanghwamun was high significant, but the correlation between 0-5 km area and 5-10 km area from Kwanghwamun had no significance. In Cd contents. Cd contents were high in Youido, Shinch on, Kongdokdong, Haengdangdong, Kirum, Ch ongnyangni and Imundong.

• 한국해양학회지
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• v.11 no.1
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• pp.1-8
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• 1976

This work concerns ecological studies on the larvae of the ark shell, Anadara broughtonii(SCHRENCK), in the aea adjacent to Gajyo-do in Jinhae Bay. Marine environmental factors, namely, temperatue, salinity, depth, and tidal current were observed in connection with the larval distributions. Water temperature appeared to be one of the main factors that influence the spawning activity. The numbers of the drifting larvae fluctuated greatly during the study period. The trend, however, was for numbers to be low in early summern, increasing in mid summer, and reaching a peak in late summer, at high bottom water temperature and low bottom salinities. Significantly increased numbers of the drifting larvae were observed during the period in which the bottom water temperatures and salinities were very close to those at the surface. the numbers of the drifting larvae showed a positive relationship with velocities of the water mass within the range of 0∼20 cm/sec. It was also noticed that the drifting larvae were relatively abundant in the area of eddy motion.

• Nuclear Engineering and Technology
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• v.36 no.6
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• pp.559-570
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• 2004

A computational fluid dynamics model for predicting moderator circulation inside the Canada deuterium uranium (CANDU) reactor vessel has been developed to estimate the local subcooling of the moderator in the vicinity of the calandria tubes. The buoyancy effect induced by the internal heating is accounted for by the Boussinesq approximation. The standard $k-{\varepsilon}$ turbulence model with logarithmic wall treatment is applied to predict the turbulent jet flows from the inlet nozzles. The matrix of the calandria tubes in the core region is simplified to a porous media in which the anisotropic hydraulic impedance is modeled using an empirical correlation of pressure loss. The governing equations are solved by DFX-4.4, a commercial CFD code developed by AEA technology. The resultant flow patterns of the constant-z slices containing the inlet nozzles and the outlet port are "mined-type", as observed in the former 2-dimensional experimental investigations. With 103% full power for conservatism, the maximum temperature of the moderator is $82.9^{\circ}C$ at the top of the core region. Considering the hydrostatic pressure change, the minimum subcooling is $24.8^{\circ}C$.

• Journal of Radiation Protection and Research
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• v.11 no.1
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• pp.77-82
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• 1986

Determination of the relation between the kerma(Kinetic Energy Released in Material) and the absorbed dose is one of the basic problems of dosimetry. Kerma and absorbed dose were measured for 6 MV X-ray from the high energy medical linear accelerator and $^{60}Co$ gamma-ray. The experimental results show that the absorbed dose in the transient equilibrium region practically coincide with the kerma in water and Al for $^{60}Co$. The maximum dose depths were $1.45g/cm^2$ for 6MV X-ray and $0.48g/cm^2\;for\;^{60}Co$ gamma-ray. The ratios of the absorbed dose at maximum build-up to the collision kerma at the surface, ($K^{att}$), were 0.949 for 6MV X-ray and 0.992 for $^{60}Co$ gamma-ray. No difference was found between water and Al when the standard field size was used. This results show that the dependence of $K^{att}$ on the material is very small.

• Proceedings of the KSME Conference
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• 2001.11b
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• pp.499-504
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• 2001

A validation of a 3D CFD model for predicting local subcooling of moderator in the vicinity of calandria tubes in a CANDU reactor is performed. The small scale moderator experiments performed at Sheridan Park Experimental Laboratory(SPEL) in Ontario, Canada[1] is used for the validation. Also a comparison is made between previous CFD analyses based on 2DMOTH and PHOENICS, and the current model analysis for the same SPEL experiment. For the current model, a set of grid structures for the same geometry as the experimental test section is generated and the momentum, heat and continuity equations are solved by CFX-4.3, a CFD code developed by AEA technology. The matrix of calandria tubes is simplified by the porous media approach. The standard $k-\varepsilon$ turbulence model associated with logarithmic wall treatment and SIMPLEC algorithm on the body fitted grid are used and buoyancy effects are accounted for by the Boussinesq approximation. For the test conditions simulated in this study, the flow pattern identified is a buoyancy-dominated flow, which is generated by the interaction between the dominant buoyancy force by heating and inertial momentum forces by the inlet jets. As a result, the current CFD moderator analysis model predicts the moderator temperature reasonably, and the maximum error against the experimental data is kept at less than $2.0^{\circ}C$ over the whole domain. The simulated velocity field matches with the visualization of SPEL experiments quite well.

• Journal of Environmental Science International
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• v.9 no.3
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• pp.253-259
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• 2000

The purpose of this study is to investigate the physicochemical characteristics of salinization of groundwater at the estern area of Cheju island. For this purpose, the major ions of groundwater, spring water are analyzed. The concentration of $Cl^-$ and Na^++K^+$/ contained in the groundwater at near the coastline are higher than those at inland area away from the coastline. The water quality components of groundwater observed at this area can be classified into 4 types such as Na-Cl, $HCO_3, Na-Cl-HCO_3$ and Ca-HCO$_3$. The concentration ratio of $SO_4^1 to Cl^- is 0.1354(R^2=0.972)$ at this area. This value is very similar with Dittomer's ratio of 0.13. For Na^+, K^+, and Mg^{2+}/ versus Cl^-$, their ratios also show a significant relationship between sea water and groundwater in this area. From the chloride-bicarbonate ratio, it can be estimated that the intrusion distance of seawater from coastline to inland area is 2.8km at Onpyung-Nansan, Sangdo and Pyungdae areas, and 5.4km at Kosung-Susan area. The mixing ratio between seawater and fresh water by the intrusion of seawater is decreased with the distance toward inland from coastline. This ratio(fresh water : seawater) is 80:20 in spring water adjacent the coastlines, Onpyung area and 99.8:0.2 in the well at No.3 of Susan located at inland away from the coastline. The concentration of $Na^+$ observed at field is 25~45% lower than that theoretically calculated by this mixing ratio. Based on the data of EC, the equipotential line of 500$\mu$mhos/cm is located at 4~5km poing at Kosung-Susan area and 2.5km point at the other area. The equation of correlation between $Cl^-$ concentration and EC values is $Cl^-$=0.1927EC-16.683 for the area lower than 500 $\mu$mhos/cm and $Cl^-$=0.2773EC for the area beyond 500 $\mu$mhos/cm.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.555-560
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• 2003

Korean High Speed Train(KHST) has been tested on the high speed test line in Osung site of Korea High Speed Rail Construction Authority (KHRC). since it was developed as G7 Project Plan In 2002. This paper introduces the dynamic test devices in KHST and shows the comparison between the results of test and theoretical computing results which derive from the new model for KHST dynamic behavior. Previous computer simulation model for KHST was developed to review wether the vehicle system was satisfied with the dynamic performance requirements during the design procedure. But It should be applied the results of the parts test for suspension elements in order to compare between the results of computation and real test. Using VAMPIRE Program made by AEA Technology in UK. the new model also was modified. This paper shows that the static wheel loads calculated from new model is similar to test results. For test on high speed line, we prepared the test devices for evaluating the dynamic performances. which was consisted of the accelerometers( based on Kisler Co.) and the data aquisition systems (based on National instrument Co.), and test program coded by LabView 6i program. These lest devices and programs are flexible to extension the channels for adding sensors and connect to the ethernet network. The acceleration of car bodies, bogie frames and axle boxes were compared between the results of computation and test at 150km/. This paper shows that the results of test were high in high frequency band range but similar frequency band range. It might be considered that these differences were caused by the test which did not performed at constant speed for comparison analysis. Also. It will be able to understand the differences and make better results through a lot of tests planed in future.