• Nuclear Engineering and Technology
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• v.27 no.5
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• pp.701-709
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• 1995

The realistic discharge coefficient for the critical How model of RELAP5/AOD3/KAERI are determined for the subcooled and too-phase critical flow by assessments of nine MARVIKEN Critical flew Test(CFT). The selected test runs include a high initial subcooling and large nozzle aspect rat-io(L/D). The code assessment results show that RELAP5/MOD3/KAERI over-predicts the subcooled critical flow and under-predicts the two-phase critical flow. Using these result, the realistic discharge coefficients of critical flow models are quantified by an iterative method. The realistic discharge coefficients are determined to be 0.89 for the subcooled critical How and 1.07 for the two-phase critical flow, and the associated standard deviations are 0.0349 and 0.1189, respectively. The results obtained from this study can be applied to calculate the realistic system response of Large Break Loss of Coolant Accident and to evaluate the realistic Emergency Core Cooling System performance.

• PNF and Movement
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• v.21 no.1
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• pp.37-45
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• 2023

Purpose: Whiplash-associated disorder is often caused by external impact, such as a car accident, and it involves acceleration and deceleration of the flexion and extension of the neck. The purpose of this study is to determine whether the combination of cyrotherapy and a joint mobilization intervention in patients with acute whiplash-associated disorder is effective for pain, cervical range of motion (ROM), and muscle tone in the neck muscles. Methods: In this study, 20 patients with acute whiplash-associated disorder were randomly assigned to two groups. Group A was treated with cyrotherapy for 5 minutes, while group B was treated with cyrotherapy and a joint mobilization intervention. In both groups, visual analogue scale (VAS), neck disability index (NDI), cervical ROM, and muscle tone values were measured pre- and post-intervention. Results: According to the VAS values, both groups showed significant differences pre- and post-intervention (p<0.05), and in both groups, NDI was significantly decreased pre- and post-intervention (p<0.05). Finally, in terms of muscle tone, both groups showed significant changes before and after the intervention (p<0.05). Conclusion: These results showed that cryotherapy and joint mobilization can be effective interventions in patients with whiplash-associated disorder. In addition, to improve the ROM of the cervical joint and reduce NDI, the combination of cryotherapy and joint mobilization is considered more effective than the single intervention of cryotherapy.

• The Journal of Engineering Geology
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• v.23 no.2
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• pp.149-160
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• 2013

Volcanic activity commonly creates a highly complicated volcanic complex due to the admixture of lava flow and sedimentation of volcanic ash. The Song-Gok site is composed of volcanic rocks that collapsed at the lower part of the slope, in combination with several discontinuities in and around a fault. The results of projection analysis indicated the possibility of plane, wedge, and toppling failure in the failure section. The results of discontinuity modeling using the Distinct Element Method (DEM) revealed a total displacement of 207 mm and a joint shear displacement of 114 mm. The yield surface zone was verified at the fault plane of the failure section. In geotechnical terms, volcanic rock slopes are characteristically vulnerable to failure because of differential weathering among the various rock types, the effect of groundwater based on the permeability of the rocks, and the presence of systematic joints generated by the cooling and contraction of lava. When considering the stability of a volcanic rock slope, it is necessary to consider data such as the geological features of the rock, as obtained through detailed geological survey, and variations in discontinuities and rock blocks.

• Journal of Conservation Science
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• v.9 no.1
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• pp.1-10
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• 2000

In 1993, many bronze artifacts were excavated from the Sanoesa Temple(思惱寺), Chongju, Chungbuk. Twelve items were selected and chemically analyzed with AA Spectrometry and ICP-Atomic Emission Spectrometry. They were also observed under the optical microscopy and SEM. According to the results from chemical analysis, production method and use, these artifacts were classified into four groups: casting, wrought and welding products, and bells. Cast products, probably used for ritual, were alloy of 70% Cu, 10% Sn and 20% Pb. They showed ${\alpha}+{\beta}$ phase as a typical microstructure of casting. The ${\delta}$ phase was rarely observed due to the small amount of Sn. These artifacts included more lead than other alloys. They showed segregation like island-shape on the lead part. Wrought products used for daily too1s. were alloy of 80% Cu and 20% Sn. Since they were consist of ${\alpha}$ phase and martensite ${\beta}$ phase, it could be presumed that they were heat-treated. The production method could be identified from twinned grains in ${\alpha}$ phase. Lead was not included in because it had a bad effect to alloy. The bells were alloyed with 85% Cu, 10% Sn, 5% Pb or 90% Cu and 10% Sn. They show the dendrite structure because they were cast and alloyed with many tin. Weldinged were alloyed with 83% Cu, 12% Sn and 5% Pb. lt showed the fine dendrite structure because of fast cooling in air.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.6
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• pp.453-458
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• 2002

High temperature sterilization method (30min. at $40^{\circ}C$longrightarrow30 min. at $70^{\circ}C$longrightarrow30 min. cooling at $20^{\circ}C$) was evaluated better than that of chloride, ion water, $O_3$ water, and salt water for the controling of micro-organisms at the early stage of sprout culture. Due to the improved germination rate and effective control of micro-organisms at early stage, the method resulted in much lower in the number of micro-organisms, higher in sprout yield, and 2 days longer in quality keeping at market than sprouts prepared by conventional method. There are two methods related with water temperature; constant temperature method (18.5$\pm$ $0.5^{\circ}C$) which keeps the same water temperature during the culture and 3-stage temperature method which changes the water temperature depending on the days after culture. Three-stage temperature method set the temperature at 21$\pm$ $1^{\circ}C$) in the second and third days after the initial acceleration of germination (about 4 hours), at 18.5$\pm$0.5$^{\circ}C$ in the fourth and fifth days, and at 17.0$\pm$ $0.5^{\circ}C$) in the sixth and seventh days. Three-stage temperature method could enhance the resistance power to diseases at the early growth stage, control the growth to standard goods (8-9cm in length and 2.15-2.30mm in width), and keep good body color at the middle or final stage. This method also increased the sprout yield by 6% compared with the conventional method, constant temperature method.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.117.1-117
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• 2003

새송이 버섯은 맛과 향이 좋고 영양적으로 우수하여 성인병 예방과 개선 효과가 있다고 알려져 있으나 재배농가의 급증으로 인한 가격하락과 집중출하로 신선도의 하락 등이 문제가 되고 있어 새송이 버섯의 활용성을 향상시키고, 소비자의 기호를 충족시킬 수 있는 버섯류 가공품 개발이 요구되고 있다. 전통절임식품을 응용한 새로운 버섯류 장류절임 가공법을 개발하기 위하여 절임 전 처리에 따른 품질특성을 비교하였으며, 이를 위하여 먼저 절임 전처리 조건으로 블랜칭처리, 적정 염농도와 처리시간 및 탈염법을 개발하고 건조 등의 전처리에 따른 품질 평가는 수분함량, 염도, 색상, 조직감, 관능특성 등을 평가하였다. 새송이 버섯을 전처리하기 위한 블랜칭 처리조건은 7$0^{\circ}C$에서 10분간 처리한 구가 조직감이 우수하고 갈변이 적었으며 염 침지시간은 침지 72시간까지는 증가하였으나 그 이후로는 증가하지 않았고 4$0^{\circ}C$에서 탈염하는 것이 가장 우수하여 전처리 조건으로 선정하였다. 전처리 방법에 따른 중량변화는 블랜칭 처리가 약 10% 정도 중량이 더 많았으며 이 영향은 건조 후에도 지속되었다. 수분함량도 블랜칭 처리가 높았으며 염도 또한 건조 처리에 따라 높은 함량을 보였으나 블랜칭 처리를 병행했을 경우 낮은 값을 나타내었다. 조직의 강도는 무처리에 비하여 전처리를 함에 따라 많은 힘이 소요되어 질긴 조직 특성을 나타냄을 알 수 있다. 관능평가 결과 블랜칭 처리를 단독으로 실시한 B(B)처리구가 관능적 특성치 모두 높은 값을 보여 전처리 방법으로는 가장 우수한 전처리 방법임을 알 수 있었다.저온 장시간 처리한 경우에 비하여 낮은 수준이지만 약간의 증감 경향을 보이다가 고른 평형 상태를 유지하였다. 산소 농도는 저온 장시간 처리 직후 급격히 저하된 후 다시 증가하였으며 저장 7일 후에는 4$0^{\circ}C$ 3시간 처리구를 제외하고는 평형 상태를 유지하였다. 고온 단시간 처리구의 경우 처리 직후부터 저장 7일 후까지 고른 평형 상태를 유지하였다. 에틸렌의 경우 저온 장시간 처리구는 처리 직후 그 농도가 급격히 상승하였다가 저장 1일 후부터 대조구보다 낮은 값을 나타내었다. 고온 단시간 처리구의 경우 저온 장시간 처리구와는 달리 저장 1일 후부터 그 농도가 다소 상승되었다가 다시 감소는 경향을 보였다. 한편 열처리하여 냉각시킨 직후 및 저장1주 후 사과의 pH, 산도, 당도, 경도, 과육의 갈변도 등을 조사하였던 바 대조구 및 처리구간에 일부 항목에 있어서는 약간의 차이를 나타내었다. 대치할 수 있을 것이라고 사료된다. 수분함량은 기계적 검사보다 관능검사와 더욱 높은 상관관계를 나타냈다.내었다. 항균활성이 우수한 생약재를 농도별로 활성을 조사한 결과, 물 추출물과 10% Ethanol 추출물 모두 낮은 농도에서도 우수한 항균활성을 나타내었다.취와 함께 점질성 갈변물질이 생성되었다. 이와 같은 결과로 볼 때, BAAG의 처리는 BAAC의 경우보다 가격은 저렴하면서도 항균력은 우수한 천연 항균복합제재로써 농산물 식품원료에 적용하여 선도유지 기간을 연장할 수 있는 효과를 기대할 수 있었다. 과일 등의 포장제로서 이용할 가능성을 확인하였다.로 [-wh] 겹의문사는 복수 의미를 지닐 수 없 다. 그러면 단수 의미는 어떻

• Journal of Radiation Protection and Research
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• v.8 no.2
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• pp.15-35
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• 1983

High voltage paper-electrophoresis of fission products from 24 hour neutron-irradiated and 150 days-decayed 90% highly enriched uranyl nitrate solution has been carried out by using the specially designed migration apparatus. The separation of Zr-95 and Nb-95 from the other fission products is possible under the migration condition of 0.1 $M-HClO_4$ (pH=0.85), 0.05 M-HCl+0.09M-KCl (pH=0.9), 0.1M-HCl (pH=1.1) and 0.01 M-HCl (pH=2.0). Zr-95 and Nb-95 are separated out at+1cm from the fiducial point. The separation of Zr-95 and Nb-95 from each other is possible under the migration condition of 0.1 $M-HClO_4$, 0.05 M-HCl+0.09 M-KCl, 0.1 M-HCl and 0.1 M-HAc+0.1 M-NaAc (pH=4.68) together with 2% ammonium oxalate. Nb-95 is separated out at $-6{\sim}-7cm$ from the fiducial point and Zr-95 at $+1{\sim}-lcm$. The separation of Ru-103 from the other fission products is possible under the migration condition of 0.025 $M-Na_2CO_3+0.025\;M-NaHCO_3$ (pH=10.0), 0.01M-$Na_3PO_4$ (pH=11.7) and 0.1 M-NaOH (pH=13.2). Ru-103 migrates towards the anode -6cm, -4cm and -3cm, respectively.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.10 no.3
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• pp.239-244
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• 2000

Synthesis and high temperature phase stability of $_{1+x}$ Co$_{y}$ Mn$_{2-y}$ $O_4$(0$\leq$x$\leq$0.2,y=0,1/9,1/6) spinel, both the excess lithium and cobalt added, have been studied. The spinel was prepared by oxalate precipitation method as the wet chemical process. Oxalate derived spinel was synthesized by heating of precipitates at temperature lower than $600^{\circ}C$. As a result of the TG-DTA and XRD analysis of prepared and quenched powders, it was found that reversible phase transitions started at temperatures $T_1$, $T_2$및 $T_{2'}$. The transitions involved weight (oxygen) loss and gain during heating and cooling. The effects of Li excess and Co doping on the spinel lattice constant, phase stability and transition temperatures of the prepared powders are investigated. This study would provide important data for determining the spinel preparation process such as synthesis temperature and cooling speed.

• Economic and Environmental Geology
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• v.26 no.2
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• pp.117-127
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• 1993

Ag-Au vein ores from the Weolyu mine, Youngdong district, contain significant germanium (up to 145g/t, average 34.9g/t), in the form of argyrodite ($Ag_8GeS_6$). Mineral chemistries of argyrodite and its associated minerals were determined by electron probe microanalysis. Twenty eight elements in thirteen ore samples were analyzed using an ICP mass spectrometer. Argyrodite occurs in the paragenetically later mineral assemblage consisting of carbonates+quartz+native silver+argentite+Ag-sulfosalts, indicating that the germanium mineralization represents the culmination of a complex mineral sequence which includes early gold and late silver deposition. The mean formula of the argyrodite is $Ag_{7.90}\;(Ge_{0.76}Sn_{0.04})S_6$, with minor amounts of Cu, Fe, Sb, As, Sn, and Zn. The Weolyu argyrodite shows systematic substitutions of Ag by Cu, and of Ge by Sb. Chemical analyses of vein ores indicate that metals were precipitated in the order of $Fe{\rightarrow}Pb$, $Zn{\rightarrow}Cu{\rightarrow}Ag$, Sb, As, Ge. Germanium has a strong geochemical affmity with As and Sb, and Cu, Pb, Zn, Mo, and Sr show weak positive correlations with Ge. Germanium deposition at Weolyu was mainly a result of cooling of hydrothermal fluids (down to $175^{\circ}C{\sim}210^{\circ}C$, due to increasing involvement of cooler meteoric waters in the epithermal system.

• Korean Journal of Crystallography
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• v.4 no.2
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• pp.74-85
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• 1993

Single crystals of LiNbO3 have found extensive application in electro-optic and nonlinear optic devices. However, laser-induced refartive index inhomogeneities, which have been labeled opical damage impose limits on device optical damage in LiNbO3 is imporved if more than 4.5 rml% MgO is added to the melt The laser damage thrueshold increased as much as 100 times better then that of undoped crystals. The MgO doped cystal has thus been urterlsiv81y studied since then. In the study, Mgo:LiNbOs(MLA) single crystals dopsd with 0, 2.5, 5.0, 7.5, 10.0 mol% MgO have been grown by the czocrualski technique. The metls were prepared in the platinum crluible and 15∼20mm diameter crystals were grown with a length of 20∼30mm in a resitance heater. The growth rate was 2.5mm/hr, the rotation speed 15rpn. Before sawing MLN single crystals were annealed for 24 hours under atmosphere at a temperature of 1080℃. After sawing, we have found an annual ring cross section of MNA crystals only in the direction of perpendicilar to the c-axis. Nonuniform dispusion of MgO was pointed out that the cuties of the state of oxide were strongly affected by oxygen partial pressure in.