• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.19 no.4
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• pp.517-532
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• 2021

Safe geological disposal of spent nuclear fuel (SNF) requires knowledge of the deep hydrochemical characteristics of the repository site. Here, we conducted a set of deep hydrochemical investigations using a 750-m borehole drilled in a model granite system in Wonju, South Korea. A closed investigation system consisting of a double-packer, Waterra pump, flow cell, and water-quality measurement unit was used for in situ water quality measurements and subsequent groundwater sampling. We managed the drilling water labeled with a fluorescein dye using a recycling system that reuses the water discharged from the borehole. We selected the test depths based on the dye concentrations, outflow water quality parameters, borehole logging, and visual inspection of the rock cores. The groundwater pumped up to the surface flowed into the flow cell, where the in situ water quality parameters were measured, and it was then collected for further laboratory measurements. Atmospheric contact was minimized during the entire process. Before hydrochemical measurements and sample collection, pumping was performed to purge the remnant drilling water. This study on a model borehole can serve as a reference for the future development of deep hydrochemical investigation procedures and techniques for siting processes of SNF repositories.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.2
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• pp.89-96
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• 2019

This study was conducted to investigate 106 grassland farms in six provinces including Chungcheongbuk-do, Gangwon-do, Gyeonggi-do, Gyeongsangbuk-do, Gyeongsangnam-do, Jeju-do, and Jeollanam-do to present their problems and causes by surveying the actual state of grassland farms during three years(2014~2016). The grassland survey was divided into three categories; used as the perennial grasses and annual forage crops (Complied with Grassland Act), not used as the perennial grasses and annual forage crops (Not complied with Grassland Act) and failed to meet the farmer and some items are missing or inaccurate (Insufficient contents). Among the surveyed grassland farm, 68 farms (64.2 %) were complied with Grassland Act but 30 farms (28.3 %) were not complied with Grassland Act. Especially, the 8 farms (26.7 %) not complied with Grassland Act used the grassland as other purposes such as tree growing, golf club and swine farm etc.. Therefore, strict on-site investigation by local governments is required to prevent the grassland from being used by illegal purposes. And there's a strong likelihood that 5 farms (62.5 %) avoided the survey violate the positive law. Grassland grades used by the local administrative agencies were not influenced by the factors affecting the yield (existence and non-existence of overseeding and fertilization by grassland grade, soil pH and organic matter content). This results suggest that there is a fundamental problem on the current grassland grade system based on the yield and the irregular time of investigation and lack of on-site investigation are another causes for inaccurate grassland grade. Therefore, the new method evaluating grassland grades which is not based on yield and the thorough on-site investigation by local administrative agencies are necessary when the grassland grade is evaluated.

• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.817-823
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• 2003

We have performed ab initio calculation on the active site of HIV-1 protease. The FEP method was used to determine the binding free energy of four different of protonated states of HIV-1 protease with inhibitor. The structure of the active site and hole structure was taken from the X-ray crystallographic coordinates of the C₂ symmetric inhibitor A74704 protease bound. The active site was modeled with the fragment molecules of binding pocket, acetic acid/ acetate anion (Asp25, Asp125), formamide (amide bond of Thr26/Gly27, Thr126/ Gly127), and methanol as inhibitor fragment. All possibly protonated states of the active site were considered, which were diprotonated state (0, 0), monoprotonated (-1, 0),(0, -1) and diunprotonated state (-1, -1). Once the binding energy Debind, of each model was calculated, more probabilistic protonated states can be proposed from binding energy. From ab-initio results, the FEP simulations were performed for the three following mutations: Ⅰ) Asp25 … Asp125 → AspH25 … Asp125, ⅱ) Asp25 … Asp125 → Asp25 … AspH125, ⅲ) AspH25 … Asp125 → AspH25 … AspH125. The free energy difference between the four states gives the information of the more realistic protonated state of active site aspartic acid. These results provide a theoretical prediction of the protonation state of the catalytic aspartic residues for A74707 complex, and may be useful for the evaluation of potential therapeutic targets.

• Journal of Korean Critical Care Nursing
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• v.15 no.3
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• pp.75-87
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• 2022

Purpose : This retrospective investigation study aimed to determine the predictive validity of superficial surgical site infection assessment tools by measuring the risk score at the surgical site. Methods : This study included patients hospitalized to the general surgery department of a Hospital from January 2021 to December 31, 2021. The inclusion criteria were age ≥19 years, general abdominal surgery under general anesthesia, and hospital stay longer than 2 days. Patients who had undergone transplantation were excluded. Results : Tool validity results showed that tools including surgical time and operative procedure were more accurate than previously developed tools, with a sensitivity of 71.1%, specificity of 71.4%, positive prediction of 12.3%, negative prediction of 97.8%, and area under the curve of 0.743 (95% confidence interval, 0.678~0.745). The tool's cut-off score was 15, and the risks of infection was increased by 6.14 times at or above this cut-off point. Preoperative hair removal period, surgical wound classification, surgery time, body temperature on the second day after surgery, drainage tube type, and suture type affected the risk of infection at the surgical site. Conclusion : The incidence of healthcare-associated infections has been declining in the past decade; however, surgical site infections still account for a considerable proportion. Therefore, early identification of high-risk groups for surgical site infection is crucial for reducing the incidence of surgical site infection using appropriate management.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.20 no.6
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• pp.131-137
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• 2018

The two recent excavations at the site of Beopsusa Temple in Seongju revealed that it contained eight building remains, three pedestrian facilities, four drainage facilities, two walls, three embankments, and an estimated pagoda remain. Even though this investigation was restricted to some sections of the site, it confirmed remains of architectural significance and thus attracted the attention of concerned researchers. This study thus set out to make an architectural survey of the site based on the excavation results and examine the characteristics and nature of remains of Buildings No.2 and 3 at the site. The planar analysis results show that Building No.2 (Remains 2-2) at the site of Beopsusa Temple was a gable-roofed building with a single story including 6 kan(間) in the front and 4 kan(間) in the flank and that Building No.3 (Remains 3-3) was a single-story building with a hipped-and-gable roof including 5 kan(間) in the front and 3 kan(間) in the flank. The most noteworthy remain of this excavation was the north-south square platform discovered at the Building No.2 at the site. It is estimated as a high chair platform used for Buddhist sermons. It was confirmed only at the lecture hall remains of Hwangnyongsa Temple and Anyangsa Temple in the nation and had never been found at remains related to Chinese and Japanese Buddhist Temples, being regarded as a very important and unique artifact. Since it was found at the remains of Building No.2, they was estimated as the lecture hall remain at the site. Found at the remains of Building No.3 at the site, the oblong altar remains were also very unique and rare and never found at other Buddhist temple sites. The inside of oblong altar was evenly covered with roof tiles instead of rubble, and there were small crushed stones for internal division, which is an altar construction method distinctly different from its counterparts at other Buddhist temple sites. Those findings raise the possibility high that a wooden facility was put up at the top of oblong remains.

• Journal of Conservation Science
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• v.18 s.18
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• pp.5-18
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• 2006

Dujeong-dong site of Cheonan is known as the site of Baekje period in the first half of the fourth century. This study investigated the visible properties and the chemical composition of the 18 pieces of the glass found in the site, and considered scientific properties and periodic interrelationship of the glass on the basis of the analysis result. The observation of the visible properties and microstructure of ancient glass was performed with both an electron microscope and an optical microscope, and the chemical composition was conducted by way of both quantitative and qualitative analysis using Scanning Electron Microscope(SEM) with Energy Dispersive Spectrometer(EDS). In the analysis result, various chemical composition systems are identified in the glass beads of Dujeong-dong site, such as lead-barium, soda and potash glass, and also different shapes were found such as gold foil glass beads, tubular beads, and round beads. It is estimated that the classification of glass by means of its chemical composition was also closely related to the color of glass.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E4
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• pp.191-201
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• 2002

The pH, electric conductivity. and the major ionic components were analyzed for the precipitation samples collected at 1100 Site of Mt. Halla and Jeju city. The quality of analytical data was verified by the comparison of ion balances, conductivities and acid fractions, all of which correlation coefficients were over 0.952. The ionic strengths lower than 10$^{-4}$ M were found in 57 and 28% at 1100 Site and Jeju city respectively. The precipitation in Jeju city was influenced more by the oceanic effect than those in 1100 Site. The acidification of precipitation was caused mostly by S $O_4$$^{2-}$and N $O_3$$^{[-10]}$ in both areas, and the organic acids have contributed to the acidity with only 7~8%. The neutralization factors by N $H_3$ were about 44 and 47％ at the 1100 site and the Jeju city, respectively, whereas those by CaC $O_3$were 21 and 24%, and the free acidity were about 38 and 28％ at two sites. From the investigation of seawater and soil enrichment factors, the S $O_4$$^{2-}$, N $O_3$$^{[-10]}$ and N $E_4$$^{+}$ were immigrated by other sources rather than from the seawater or soil origins. but not in the case of $Mg^{2+}$, C $l^{[-10]}$ , N $a^{+}$, and $K^{+}$. Factor analysis has shown that the precipitation at the 1100 site had been influenced mostly by anthropogenic sources, followed by soil and sea-water sources. On the other hand, the precipitation at the Jeju city was mainly influenced by oceanic sources, followed by anthropogenic and soil sources.urces.

• Journal of Korean Tunnelling and Underground Space Association
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• v.15 no.4
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• pp.415-429
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• 2013

Performance-based design is becoming a key word for structure design in architectural and civil engineering spheres. In this paper, the need of the performance-based design, especially for tunnels, was enhanced by case study on the largely deformed cut-and-cover arch tunnel built by the prescribed design. In addition, this paper introduces effective method of subdivision on tunnel performance to help field engineer's comprehension. Case study dealing with the issue of typical backwards problem in geotechnical engineering was examined. First of all, the outline of the damaged culvert as well as the surrounding embankment is in detail described. The background, together with the cause of damage, is discussed based on the results of site investigation. Secondly, it was attempted to elucidate the deformation mechanism of the embankment by means of numerical analysis, and the countermeasures are proposed. Finally, the stability of the embankment with the countermeasures was evaluated.

• 한국신재생에너지학회:학술대회논문집
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• 2005.11a
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• pp.587-590
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• 2005

A detailed geothermal characteristics survey with numerical simulations of the heat transfer in a site for ground source heat pump system is necessary for deploying a shallow geothermal utilization system. Density, specific heat, thermal diffusivity, and thermal conductivity are measured on 91 core samples from a 300 m deep borehole in KIGAM(Korea Institute of Geoscience and Mineral Resources). The heat flow is estimated from the thermal gradient and average thermal conductivity and the correlation between fracture system and hydraulic conductivity is analyzed. From the obtained ground information of the study site the performance of the ground heat pump system can be analyzed with some detailed numerical simulations for seasonal heat pump operation skill and optimal system design techniques.

• The Korean Journal of Ecology
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• v.25 no.1
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• pp.51-58
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• 2002

An investigation of occurrence and distribution of dictyostelid cellular slime molds in South Korea were carried out. Thirty-one dictyostelid cellular slime molds were isolated from soils of 256 sample sites of 41 area within mountain forests, riversides, streamsides and coastal area in South Korea. The average number of species isolated at a given study area was 6.85. Based on the distribution value calculated from average frequency and site presence, four dictyostelid species distributed widely in South Korea; Polyspondylium pallidum, P violaceum, Dictyostellium mucoroides and D. minutum. Especially, P pallidum. were found in 30 area and the highest site presence. Eight dictyostelid species was described firstly in this study: D areum var. luteolum, D. delicatum, D. deminutivum, D. implicatum, D. microsporum, D. mucoroides var. stoloniferum, D septentrionalis, and P. candidum.