• Nuclear Engineering and Technology
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• v.29 no.5
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• pp.375-384
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• 1997

Relative power density distributions of the Kori Unit 1 pressurized water reactor are calculated by Monte Carlo modeling with the MCNP code. The Kori Unit 1 core is modeled on a three-dimensional representation of the one-eighth of the reactor in-vessel component with reflective boundaries at 0 and 45 degrees. The axial core model is based on half core symmetry and is divided into four axial segments. Fission reaction density in each rod is calculated by following 100 cycles with 5,000 test neutrons in each cycle after starling with a localized neutron source and ten noncontributing settle cycles. Relative assembly power distributions are calculated from fission reaction densities of rods in assembly. After 100 cycle calculations, the system converges to a k value of 1.00039 $\geq$ 0.00084. Relative assembly power distribution is nearly the same with that of the Kori Unit 1 FSAR. Applicability of the full-scope Monte Carlo simulation in the power distribution calculation is examined by the relative root moan square error of 2.159%.

• Restorative Dentistry and Endodontics
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• v.26 no.1
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• pp.32-40
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• 2001

The aim of this study was to evaluate the effect of various polymerization techniques on the microleakage of compomer restorations. Fifty extracted human premolars and molar were used and randomly divided into 5 groups. After cavity preparation, compomer (F2000$^{\circledR}$) was filled according to the manufacturer's directions. All groups, except group 5, were filled using an incremental technique. Group 1 was polymerized for 40 seconds at a continuous 485mW/$\textrm{cm}^2$ with a VIP$^{\circledR}$(Bisco, USA) light cure unit. Group 2 was polymerized for 20 seconds at 345mW/$\textrm{cm}^2$ and then for 20 seconds at 645mW/$\textrm{cm}^2$ with the VIP equation omitted light cure unit. Group 3 was polymerized at 400mW/$\textrm{cm}^2$, gradually increased to 50mW/$\textrm{cm}^2$ 10 seconds until 550mW/$\textrm{cm}^2$ was reached; total 40 seconds with a Spectrum 800$^{\circledR}$ (Dentsply Caulk, USA) light cure unit. Group 4 was polymerized for 3 seconds using an incremental technique with a Flipo$^{\circledR}$ (LOKKi, France) light cure unit. Group 5 was polymerized for 3 seconds using a bulk fill technique with the Flipo$^{\circledR}$ light cure unit. The specimens were embedded with acrylic resin, and were sectioned with diamond saws in a mesiodistal direction along the longitudinal axis of the tooth so as to pass through the center of the restoration, and three surfaces (occlusal, pulpal, and gingival) were examined with SEM. The results were as follows ; 1. Group 5 showed a significantly larger gaps compared to other groups on the gingival, occlusal, and pulpal walls. 2. All groups except group 5 had no statistically significant gap on the gingival, occlusal, and pulpal walls. 3. There was no significant correlation between the amount of enamel on the gingival and occlusal walls and polymerization shrinkage.

• Korean Institute of Interior Design Journal
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• no.3
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• pp.85-90
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• 1994

The purpose of this study was to present design direction of a unit plan in elderly housing. In order to perform the above purpose, this study was organized into two sections. First, literature review to understand the relationship between late adulthood development and housing environment, unit plan of elderly housing and design needs. Second, questionnaire and field survey research to seek a design direction of unit plan. Statistics were frequency, percentage, mean and crosstabulated analysis. The major findings were summerized as follows ; 1) The size of ideal single room was 20.4$m^2$-28.5$m^2$, and the minimum size for the couple was 28.5$m^2$. 2) The entrance of each room must not be faced each other, in case of the corridor type building like YooDang village. 3) Spare heater which can be turned on anytime was requested in bathroom especially for wintertime or whenever elderly need more heat. 4) The minimum size of closet was 1.5m per single room and the ideal size of it is over 1.8m. 5) The platform ondol type bed was ideal type bed was ideal for Korean elderly.

• Journal of the Korean housing association
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• v.18 no.6
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• pp.93-101
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• 2007

This study was to find out users' satisfaction on the dormitory of high school in Jeonju City and to propose it's physical environmental improvement directions. This was performed by a questionnaire survey method, and the questionnaire was designed by researchers considering relative literatures. Data were collected from 200 students, who had been dwelling 4 high school dormitories in Jeonju City. By analyzing those data, findings were as follows: 1) Users of students were satisfied the whole of their dormitory; facilities, spaces, and living. 2) They were highly concerned about a library and a personal unit space in their dormitory. 3) They needed their personal unit space to be designed bedroom+bathroom type with 2 persons' sharing and be equipped one story bed and desk furniture. Also, they needed improvement on heating & cooling, small space and indoor air quality of unit space. 4) The users' satisfaction on unit space were 2.88, and their satisfaction of the technical factor was 2.71 that was the lowest score in them. And The functional factor was highly effected their satisfaction. 5) The space utility and the space size of functional factor, the soundproof, the heating/ventilation and the indoor quality of technical factor, and the privacy of behavior factor were highly correlative to their satisfaction of unit space.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.26 no.8
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• pp.388-393
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• 2014

Energy consumption unit in a building is classified according to uses of electricity, gas, and oil, and it has been studied steadily as a material for establishing policy standards for energy saving in buildings. Meanwhile, consumption unit in apartment house can be calculated differently according to its survey method and area standard. Therefore, with the necessity of reestablishing energy consumption unit, this study has researched thermal energy consumption, Supply dwelling area Exclusive dwelling area, completion year and housing type of 23,791 households of 31 complex in Daejeon. As a result, (1) there was about 20% difference between supply and exclusive dwelling areas. (2) On the basis of exclusive dwelling area, thermal energy consumption unit was calculated as $104.9kWh/m^2{\cdot}a$ in 2010, $104.6kWh/m^2{\cdot}a$ in 2011, and $107.7kWh/m^2{\cdot}a$ in 2012.

• Journal of Pharmaceutical Investigation
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• v.36 no.1
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• pp.19-22
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• 2006

The pharmacokinetics of nimodipine, following a single 16 mg/kg oral dose, was investigated in rabbits with hepatic failure induced by 0.5 mL/kg (mild), 1.0 mL/kg (moderate) and 2.0 mL/kg (severe) of carbon tetrachloride $(CCl_{4}$ : olive oil = 20 : 80, v/v). The plasma concentrations of nimodipine were determined by a high performance liquid chromatographic assay. The levels of sGOT and sGPT in rabbits with mild $(86.2{\pm}29.0\;and\;98.5{\pm}33.1\;unit/dL)$, moderate $(168.1{\pm}61.2\;and\;196.2{\pm}66.0\;unit/dL)$ and severe $(292.7{\pm}82.2\;and\;314.2{\pm}99.8\;unit/dL)$ hepatic failure were significantly increased compared to the control $(38.0{\pm}10.1\;and\;32.4{\pm}10.2\;unit/dL)$. The area under the plasma concentration-time curve (AUC) of nimodipine was significantly increased in mild $(131.7{\pm}28.1%)$, moderate $(168.8{\pm}32.8%)$ and severe $(204.6{\pm}58.3%)$ carbon tetrachloride-induced hepatic failure rabbits compared to the control (100%) rabbits. The volume of distribution $(V_{d})$ and the total body clearance $(CL_{t})$ of nimodipine were significantly decreased in all hepatic failure groups. The elimination rate constant $(K_{el})$ of nimodipine was significantly decreased in moderate and severe carbon tetrachloride-induced hepatic failure rabbits. There was a correlation between sGOT (y= 1.01x+241, r=0.993) or sGPT (y=0.92x +243, r=0.997) value and the AUC of nimodipine in the rabbits with hepatic failure. These findings suggest that the hepatic metabolism of nimodipine was inhibited by carbon tetrachloride-induced hepatic failure rabbits, resulting in the decrese in $V_{d}$ and $CL_{t}$ of nimodipine in the rabbits with mild, moderate and severe hepatic failure.

• Atmosphere
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• v.27 no.2
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• pp.151-162
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• 2017

The rainfall amount data measured by 'Wootaek', a method of measuring how far the moisture had absorbed into the soil when it rains during the Joseon Dynasty, were estimated with the Chugugi data in the 12 sites where both the 'Wootaek' and 'Chugugi' data are available. Excluding the 5 sites (Ganghwa, Jinju, Jeonju, Chuncheon, Hamheung) poor in sample data, the 'Wootaek' data 1 'Ri' and 1 'Seo' in 'Chugugi' unit (Bun) in the 7 sites; Suwon, Gwangju (Gyeonggi-do), Gongju, Daegu, Wonju, Haeju and Pyeongyang, were 11.1/5.6 Bun, 9.4/3.2 Bun, 14.0/5.7 Bun, 9.3/3.9 Bun, 13.6/4.3 Bun, 11.3/4.8 Bun and 16.8/7.4 Bun, respectively. The Chugugi unit 1 'Bun' is equall to approximately 2 'mm'. The average of the 7 sites is 13.1/5.7 Bun, however it becomes small to 11.7/4.5 Bun when the Pyeongyang of which data is considerably distributed over wide range is excluded, showing that the 'Wootaek' data 1 'Ri' is approximately the 2.3~2.6 times of 1 'Seo'. It is recommended to use the individual estimates of the sites in utilizing the 'Wootaek' rainfall data of 352 stations across the country restored from the "Gaksa-deungnok".

• Journal of the Korean GEO-environmental Society
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• v.14 no.10
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• pp.11-16
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• 2013

Success or failure of the bi-directional pile load test for drilled shaft depends on point selection for loading cells, that is balanced location both uplift force and downward force. Methods to evaluate the ultimate unit side resistance in rockmass layer in both domestic and foreign are based on the uniaxial compression strength of rock core, which can hardly be obtained in domestic rockmass layers which are weathered rockmass layer and soft rockmass layer with very low RQD. Therefore, this study suggested the relation charts between the revised SPT N values and developed unit side resistance of each different layers, which were obtained from bi-directional pile load tests in various domestic sites. To evaluate the appropriateness of the relation charts, the developed unit side resistances from the relation charts were used to select the loading cell position and compared with the measured unit side resistances from field pile load test. Results showed that the developed side resistance from relation charts and the measured side resistance of weathered soil layer and weathered rock layer were very close. Average developed side resistance($1,325kN/m^2$), which are average of upper soft rock layer of loading device($1,151kN/m^2$) and lower($1,500kN/m^2$), was similar with the estimated value ($1,250kN/m^2$).

• Journal of the korean academy of Pediatric Dentistry
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• v.32 no.2
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• pp.284-292
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• 2005

The aim of this study was to identify and quantify the major or detectable monomers released from any of five commercially-available, light-cured pit and fissure sealants with three different light sources : conventional halogen light curing unit, plasma arc light curing unit and LED curing unit. After curing, specimens were immediately immersed in distilled water for different time intervals. The time related release of monomers were analyzed by high performance liquid chromatography(HPLC). Identification and quantitative analysis of monomers were performed by the comparison of the elution time and the absorption peak height of the eluates with those of the authentic sample. The result of this study can be summarized as follows. 1. Standard solution peaks with retention times of 2.3, 3.2, 5.6, 6.5, 10.4 minutes were identified as BPA, TEGDMA, UDMA, Bis-GMA, Bis-DMA, respectively. 2. None of the chromatograms of the tested sealants displayed peaks with the same retention time as that of the standard solution, except for TEGDMA. 3. The highest release rate of TEGDMA was observed during the 12hr period for all samples and declined thereafter. 4. The elution of TEGDMA from curing with Halogen curing unit for 20 second and LED for 10 second was less than that resulting from curing with Plasma arc for 3 second. 5. TEGDMA was detected at much lower levels in eluates from the Pit & Fissure $Sealant^{TM}$ than other sealants. The elution of TEGDMA from the $Helioseal^{(R)}$ F cured with Halogen light curing unit, the $Concise^{TM}$ cured with Plasma arc curing unit and the $Teethmate^{(R)}$ F-1 cured with LED curing unit were higher than other sealants.

• Journal of Biosystems Engineering
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• v.30 no.6 s.113
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• pp.321-326
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• 2005

Tractor performance was analyzed using the data from 226 Korean-made and 107 imported tractors tested at the National Institute of Agricultural Engineering for the 25-year period from 1980 through 2004. The performance analysis included the specific volumetric fuel consumption (svfc), power per unit weight and traction coefficient evaluated from the viewpoint of PTO power level. No significant performance improvement has been made for the Korean-made tractors over the last 25 years. The average svfc for the maximum PTO power has increased by only $2.1\%$ from 1980 to 2004, resulting in 2.86 kW${\cdot}$h/L in 2004. The average maximum PTO and drawbar power per unit weight of ballasted tractors were 1.38 and 1.19 kW/kN in 2000-2004, indicating $14.0\%$ and $5.9\%$ decreases respectively from 1980 to 2004. The traction coefficient has increased by $23.1\%$ over the 25 years, resulting in 0.68 in the 2000-2004 period. Poor performance improvement was also observed from the imported tractors. In the 2000-2004 period, average svfc for the maximum PTO power, PTO power per unit ballasted weight, drawbar power per unit ballasted weight and traction coefficient of the imported tractors were respectively 3.0 kW${\cdot}$h/L, 1.34 kW/kN, 1.13 kW/kN and 0.68. PTO and drawbar power per unit weight were lower in imported tractors than the Korean-made tractors. Comparing the test results with those of tractors less than 37 kW tested at the Nebraska Tractor Test Laboratory from 1981 to 2002, the Korean-made tractors have exhibited better performance in terms of power per unit weight. However, poor performance in the svfc and traction coefficient was observed. The average svfc and traction coefficient of the Korean-made tractors were respectively $86.4\%$ and $83.7\%$ of the tractors tested at the NTTL over the same period.