• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.1
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• pp.69-77
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• 2014

Unsaturated hydraulic conductivity of the bentonite-buffer was evaluated using the relative humidity data. The method for calculating unsaturated hydraulic conductivity was deduced from the general analytical equation representing the movement of water in unsaturated media, which was applied to the experimental results of water infiltration tests for identifying the behavior of unsaturated hydraulic conductivity according to the water saturation. Unlike the saturated condition, the hydraulic gradient and water flux were irregularly changed, and the unsaturated hydraulic conductivity was increased with increasing the experimental time. Swelling of bentonite grains due to the water absorption increased the volume and size of pore within bentonite, resulting in the increase of water velocity and unsaturated hydraulic conductivity. This result suggested the necessity of further investigation on the correlation between the swelling degree of bentonite-buffer and unsaturated hydraulic conductivity. The method used in this study can be useful technique for evaluating long-term hydraulic performance of bentonite-buffer in the radioactive waste disposal system.

• Water for future
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• v.7 no.2
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• pp.75-82
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• 1974

본시험은 관개 및 배수 설계를 위한 기초자료 제공을 목적으로 토양수분 및 지하수위의 변화상태를 구명하고자 하는 것으로 카나다 퀴백(Quebec) 지방 저지대의 대표적인 2종의 태양인 점토와 사질로움 토양에 대해서 일차적으로 지표, 지하배수간의 토양수분과 지하수위의 변화를 연구분석한 것으로 그 결과를 요약하면 다음과 같다. 1. 2종의 토양(점토, 사질로움)에 있어서 공히 토양수분은 지표로부터 지하로 내려갈수록 증가되는 상태를 나타냈으면 이는 하층토로 내려감에 따라 팽창된 치밀한 토양 조직을 가지고 있음을 시사하며 2. 동기에 있어서는 지표로부터 12inch 깊이의 토양수분이 더 깊은 18inch나 24inch 깊이의 토양수분보다 증가된 상태를 유지하였다. 이는 토양내의 빙결막이나 지표면의 눈 또는 어름에 영향으로 생각되며 이 경향은 점토질 토양에서 보다 토양내 빙결막으로의 수분 이종을 조장해주는 투수 계수가 큰 사질로움 토양에서 더 높았다. 3. 양식험구 공히 지표에서 얕은 지하 0∼3inch 이내의 토양수분은 항우를 전후해서 급격한 변화를 가져왔다. 여기에서 수분의 급상승은 호우시나 표층토가 하층토의 토양수분에 영향을 주는 항우이전에 포장용수량(Field capacity)에 달했기 때문에 급항하는 지표면의 물 분자가 열에너지에 의해 증발산되고 천층에 산재한 초, 수근에 의해 소비되는 때문인 것으로 사료된다. 4. 지하수위하의 토양수분은 포화에 달하여 거의 일정할 것으로 기대되었지만 실제로 많은 변화를 가져왔다. 이들 변화에는 부분적으로 토양사극이 지하수위하이라도 채워지지 않았거나(Capillary pressure가 작을 시) 혹은 관측기간 중에 토양의 융기와 수축에 기인된다고 생각된다. 5. 지하배수구가 지표배수구에 비해 지하수위항하가 빨랐음은 물론 사질로움 토양에서는 보다 높은 투수계수로 인해서 지하수위의 항하가 점토질 토양에서 보다 훨씬 빨랐음을 보여주고 있다.표시할 수 있다.된다.acid $0.41{\sim}0.65%$, 오미자는 malic acid $1.51{\sim}3.90%$, citric acid $2.40{\sim}3.92%$로 주요 유기산이 있다. 타닌은 물보다 에탄올 추출물이 다소 함량이 높았으며 특히 오갈피는 $3.35{\sim}3.85%$로 매우 높은 함량이었다.a 6 cases, etc. 2. The retroperitoneal space including kidneys were the most commonly involved site (43.5%), of which Wilms' tumor was the commonest. 3. About 2/3 of tumors developed under the age of 6 and the commonest lesion was Wilms' tumor and the next being neuroblastoma, teratoma, ovarian cyst and so forth. 4. In all tumors except ovarian tumor and choledochal cyst, male was more frequently affected. 5. In plain abdomen 75% of neuroblastoma crossed the mid line while in Wilms' tumor only 2 cases (14%) showed midline cross. Calcific density was 입력불가 in all 6 cases of teratoma (100%) as dense and discrete ossification, in 3 case of neuroblatoma (38%) characteristically in diffuse stippled appearance and in one case

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.3
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• pp.167-173
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• 1979

It is preented the removable moving screen media-activated sludge (REMSMAS) process by using the biological fixed-film systems. The substrate removal kinetic difference between the aeration-only completed mixing activated sludge (CMAS) process and REMSMAS process were observed. The substrate removal kinetics were developed based on the attached and suspended microbial growths. The units of the aeration-only CMAS process were continously operated with the normal detention time of 4.5, 6, 9.5 and 12 flours studies after steady-state condition and the operating of the REMSMAS units conducted with the normal detention time of 6 and 12 hours studies in nonsteady-state condition. The feed solution was diluted 18 times to the raw starch wastewater in of order to maintain the proper COD (950mg/l) and BOD (450mg/l) concentration. Design parameters related to the suspended microbial growths were caculated by the equations used in the aeration-only CMAS model and these parameters used to evalute the kinetic constants in the REMSMAS process. The kinetic constant values of $Y_2,\;K_d,(\mu_{max})_s\;and\;K_s$ from Monod equations were respectively 0.78, 0.027/hr, 1.1/hr and 95mg/l in the aeration-only CMAS process. The value of the aera capacity (F) appeared to be $9.1\;mg/cm^2-day$ and the mean value of the saturation constant $(K_g)$ appeared to be 53.5 mg/l in the REMSMAs process. Also, the substrate removal .ate of the REMSMAS process was higher than that of the normal activated sludge process when this system was operated in steady-state condition. However, the rate was reduced as the critical operating day was approached.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.145-157
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• 2004

The cycle length design model of the Korean traffic responsive signal control systems is devised to vary a cycle length as a response to changes in traffic demand in real time by utilizing parameters specified by a system operator and such field information as degrees of saturation of through phases. Since no explicit guideline is provided to a system operator, the system tends to include ambiguity in terms of the system optimization. In addition, the cycle lengths produced by the existing model have yet been verified if they are comparable to the ones minimizing delay. This paper presents the studies conducted (1) to find shortcomings embedded in the existing model by comparing the cycle lengths produced by the model against the ones minimizing delay and (2) to propose a new direction to design a cycle length minimizing delay and excluding such operator oriented parameters. It was found from the study that the cycle lengths from the existing model fail to minimize delay and promote intersection operational conditions to be unsatisfied when traffic volume is low, due to the feature of the changed target operational volume-to-capacity ratio embedded in the model. The 64 different neural network based cycle length design models were developed based on simulation data surrogating field data. The CORSIM optimal cycle lengths minimizing delay were found through the COST software developed for the study. COST searches for the CORSIM optimal cycle length minimizing delay with a heuristic searching method, a hybrid genetic algorithm. Among 64 models, the best one producing cycle lengths close enough to the optimal was selected through statistical tests. It was found from the verification test that the best model designs a cycle length as similar pattern to the ones minimizing delay. The cycle lengths from the proposed model are comparable to the ones from TRANSYT-7F.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.5
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• pp.1-8
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• 2010

Recently subscribers in mobile communication services increase gradually, and the new multifunctional portable terminals can provide various functionalities. However this trend may not be desirable in Green IT respect because the emission of carbon dioxides emitted during operations of base station and mobile stations can cause significant effect on the emissions of carbon dioxides. In this paper the power saving scheme which can adjust slot index while the system is in a paging phase has been proposed and its performance has been evaluated. The slot cycle index can be adjusted according to individual user's property, its effect on the system performance has been investigated. In order to mitigate its adverse effect, power ramping scheme is considered and evaluated thereafter.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.24 no.3
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• pp.7-12
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• 1979

Seven hundred and forty eight rice cultivars were screened for drought tolerance at seedling stage in a special green house. A number of cultivars such as Wonkiljo, Hanyangdo, YR 52-$_{x}\textrm{BF}_7-67, Satominori, Mamoriaka, Akanomochi 114, Thkebenimochi, IR 937-55-3, IR2735-F_3B-6-2, IR 2871-53-2, $_{x}\textrm{BFI76}^9/Dwan, Khoo lliok Mali-4-2-105, Os6, Palawan, IRAT10, TOS 2583 and H-l05 seemed to be tolerant to drought at seedling stage. There was negative correlation between drought resistance score and growth of plant height and water content of culm and leaf after drought treatment, and highly positive correlation between resistance to blast and resistance to drought at seedling stage. There was no relationship between drought resistance and germination speed, plant height before drought treatment.

• Korean journal of applied entomology
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• v.40 no.1
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• pp.45-45
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• 2001

Development and predation of an aphidophagous gall midge, Aphidoletes aphydimyza (Rondani) , on the green peach aphid, Myzus persicae Sulzer, were studied under laboratory and greenhouse conditions. The developmental threshold temperature of the gall midge larvae was estimated to be $13^{\circ}C$. Larval and total developmental periods were 5.3 and 29 days at 25 $\pm$$2^{\circ}C$. The gall midge attacked more aphids as increasing density of peach aphids, and consumed 4 out of 10 peach aphids per day in a petri dish (9 cm in diameter) at maximum. In green house, the gall midge could control the density of the green peach aphids efficiently with a delayed density dependent-like pattern.

• Journal of the Korean Vacuum Society
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• v.10 no.1
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• pp.87-92
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• 2001

Magnetic Fe-Co(C) nanocapsules and Fe-Co nanoparticles were prepared by arc-discharge in two kinds of atmospheres, i.e. methane and a mixture of ($H_2$+Ar), respectively. Characterization and magnetic properties of this two kinds of ultrafine particles were investigated systematically by means of X-ray diffraction, Mssbauer spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, energy disperse spectroscopy analysis, chemical analysis, oxygen determination and magnetization measurement. Effects of carbon element, decomposed from a methane atmosphere in carbon arc process, on phase structures, magnetic states and surface characterization were studied in comparison to that of Ar element. Two ultrafine particles showed a little difference in the weight ratio of (Fe/co) and the size for Fe-Co nanoparticles was about two times bigger than Fe-Co(C) nanocapsules. The saturation magnetization of Fe-Co (C) nanocapsules was about 8% higher than that of Fe-Co nanoparticles while their phase constitutions were similar. Although no carbon could be detected by XRD measurement because of extremely thin shells on the surfaces of the cores, it is still believed that they are carbon and oxygen layers.

• Journal of the Korean Geotechnical Society
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• v.27 no.2
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• pp.17-26
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• 2011

To solve the problem of saturated dredged soil dumping area, it is possible to extend the life span of dredged soil dumping area by accelerating consolidation of dredged soil and making alluvial soil layer consolidated additionally by using dewatering method and PDF method without construction of new dumping area which entails great expense. Self-weight consolidation tests on samples from Busan and Incheon with the column of 400 mm in diameter were conducted to estimate those methods applicability to domestic dredged soil. As a result of tests, it was proved that dewatering method and PDF method were highly effective in increasing reclamation capacity of dredged soil by reduction of self-weight consolidation completion time and increase of self-weight consolidation settlement.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.218-225
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• 2014

Landslides, one of earth's natural disasters, increase every year due to heavy rainfall, and cause damage to human life and assets. This study used the SHALSTAB to predict places at risk of landslides, in accordance with the intensity of rainfall. The parameter value of transmissivity was $19.58m^2/day$, the internal friction angle $36.3^{\circ}$, and the saturated unit weight $2.03t/m^3$. The slope stability status was classified into four categories, namely: unconditionally stable, stable, unstable and unconditionally unstable. In order to evaluate the applicability of the SHALSTAB, actual landslide areas were checked, with the unstable area under 263 mm rainfall. 85.1% of them were consistent. And so we can identify the distribution of places at risk of landslides, on the basis of the intensity of rainfall by means of SHALSTAB.