• The Journal of the Korea institute of electronic communication sciences
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• v.18 no.5
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• pp.817-826
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• 2023

In this paper, a fault determination methodology based on an artificial neural network was proposed to protect the system from faults on the lines in the smart grid distribution system. In the proposed methodology, first, it was designed to determine whether there is a low impedance line fault (LIF) based on the magnitude of the current RMS value, and if it is determined to be a normal current, it was designed to determine whether a high impedance ground fault (HIF) is present using Normal/HIF classifier based on artificial neural network. Among repetitive DSP module-based algorithm verification tests, the normal/HIF classifier recognized the current waveform as normal and did not show reclosing operation for the cases of normal state current waveform simulation test where the RMS value was smaller than the minimum operating current value. On the other hand, for the cases of LIF where RMS value is greater than the minimum operating current value, the validity of the proposed methodology could be confirmed by immediately recognizing it as a fault state and showing reclosing operation according to the prescribed procedure.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.484-492
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• 2019

The aim of the present study was to compare the cold tolerance of seven different types of trees growing in southern Korea to select evergreen broad-leaved trees that can be used as street trees in large land areas experiencing climate change. The trees compared were the thorn tree, Cinnamomum camphora, Camellia japonica, Machilus thunbergii, Dendropanax morbifera, Daphniphyllum macropodum Miq., Quercus glauca Thunb., and Raphiolepis indica. When the trees were subjected to low temperature treatment, their electrolyte elution volume values appeared to increase with the decreases in the treatment temperature. The analysis of the cold tolerance of each type of tree was based on the estimated temperatures in the following order: C. japonica (-11.586℃) > R. indica (-9.348℃) > Q. glauca (-8.719℃) > M. thunbergii (-8.090℃) > D. macropodum (-7.409℃) > D. morbifera (-7.085℃) > C. camphora (-6.995℃). The relative cold tolerance difference found in the seven tree species was more than 5℃, as evaluated previously. In the Lauraceae family, the difference in cold tolerance was more than 2℃, even in the same species. The analysis showed that trees with excellent cold tolerance included Q. glauca Thunb., C. japonica, R. indica, and the thorn tree. This knowledge is required for the evaluation of the possibility of the survival of trees under cold temperature conditions in cities.

• Elastomers and Composites
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• v.41 no.2
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• pp.116-124
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• 2006

Cloud-point data to $160^{\circ}C$ and 1,000 bar are presented with poly(ethylene-co-15.3 mole% octene) copolymers ($PEO_{15}$) in pure 1-octene and mixtures of ethylene - 1-octene. The cloud-point curves for $PEO_{15}$ - ethylene - 1-octene mixture dramatically increase in pressure to as high as 1,000 bar with an increasing ethylene concentration. At ethylene concentrations less than 18 wt%, the ternary mixture has bubble- and cloud-point curves. As the ethylene concentration of the ternary mixture increases, the bubble-point curve and the single-phase region reduce. The reduction in the single phase region with increasing ethylene concentrations is the result of reduced dispersion interactions between $PEO_{15}$ and the mixed solvent. The single-phase region decreases with increasing temperatures when ethylene concentrations are lower than 36 wt%, whereas the single-phase region increases with temperatures at ethylene concentrations greater than 50 wt%. At ethylene concentrations greater than 50 wt% the effect of the polar interactions of the mixed solvent, which is unfavorable to dissolve PEO, is greater than the effect of the density of the mixed solvent. Therefore, the cloud-point pressures increase with a decreasing temperature. However, at ethylene concentrations less than 50 wt%, the cloud-point pressures decrease with temperature, because the effect of the polar interactions is less than the density effect.

• Elastomers and Composites
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• v.40 no.4
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• pp.277-283
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• 2005

LV transition curves for poly(ethylene-co-15.3 mol% octene) ($PEO_{15}$) and poly(ethylene- co-17.0 mol% octene) ($PEO_{17}$) were measured in cyclo-pentane and cyclo-hexane. Between $40{\sim}150^{\circ}C$, the LV curve for ($PEO_{15}$ + cyclo pentane) located $1.1{\sim}2.7$ bar higher than that for ($PEO_{17}$+ cyclo-pentane). In cyclo-hexane, similar behavior was observed for $PEO_{15}$ and $PEO_{17}$ solution except the pressure difference reduced to $0.9{\sim}l.6$ bar. If the backbone structure of $PEO_{15}$ were identical to that of $PEO_{17}$, the LV line for $PEO_{17}$ would locate at high pressures than that for $PEO_{15}$, since the number average molecular weight of $PEO_{17}$ (Ave. Mn=153,040) is 1.9 times higher 4han that of $PEO_{15}$ (Ave. Mn=82,200). The difference in the octene comonomer content between $PEO_{15}$ and $PEO_{17}$ is only 1.7 mole%, nevertheless this small difference in the backbone structure of the PEO greatly affected the location of the L-V curves in the mixtures comprised of PEO and cyclo-alkane.

• Korean Journal of Clinical Laboratory Science
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• v.50 no.4
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• pp.414-421
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• 2018

In this study, Gram-positive bacilli (GPB) were identified by MALDI-TOF MS and analyzed according to the quaternary and microbial strains in the blood culture medium over a two year period at a university hospital. The results were as follows. The overall positive rate of blood culture was 9.97%. In 713 isolated GPB, 410 strains (57.5%) were identified using a microflex MALDI Biotyper. The positive rate of GPB among the blood culture positive bacteria was 8.2%, and the quarterly isolation rate was 9.8% in the third quarter of 2015, 8.7% in the second quarter of 2016, 8.1% in the third quarter of 2016, 8.1% in the first quarter of 2015, 7.9% in the first quarter of 2015, 7.9% in the second quarter of 2015, 6.8% in the first quarter of 2016, and 6.7% in the fourth quarter of 2015. The isolates were Corynebacterium striatum 89 (12.4%), Bacillus cereus 60 (8.4%), Bacillus subtilis 30 (4.2%), Paenibacillus urinalis 29 (4.1%), and Listeria monocytogenes 25 (3.5%). The results of 16S rRNA sequencing of 43 isolates (86.0%) were consistent with those of the other 50 isolates. Five out of the seven unmatched weeks were not identified by MALDI-TOF MS.

• Korean Journal of Heritage: History & Science
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• v.49 no.4
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• pp.180-195
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• 2016

Since being designated as an important Intangible Cultural Property, Yeongsanjae has become recognized as a unique representation of Buddhist rituals in Korea. Following vigorous research in recent years, however, Suryukjae(水陸齋) was found to have been performed for a longer period and on a larger scale than Yeongsanjae, and under state leadership. This allowed researchers to move beyond the previous perspective that Yeongsanjae(靈山齋) lay at the center of many rituals. This study aims first to examine the origin and development of Yeongsanjae in Korea based on the literature, and then to discuss the meaning it holds today. Yeongsanjae was recorded as a ritual in Jineongwongong -published in 1496 during the early Joseon Dynasty- and also appeared in Yeongsandaehoejakbeopjeolcha -published in 1634(the 12th year of Injo's reign) in the mid-Joseon Dynasty and it was called Yeongsandaehoejakbeopjeolcha. It continued into the late Joseon Dynasty and it was called Yeongsanjakbeop or Yeongsandaehoejakbeop in the Ojongbeomeum collections(1661), CheonjimyeongyangSuryukjaeuiBeomeumsanbo collections(1721), and Jakbeobguigam(1826). In modern times, it has been called Yeongsanje in newspaper articles of TongnipSinmun (The Independent) and Yeongsanjae in Seokmunuibeom(1935). Nevertheless, the difference between the early Joseon Dynasty and subsequent periods is whether mourning of the spirit(唱魂) is added. In this regard, Yeongsanhoe in the early Joseon Dynasty mainly concerned Buddhist teachings realized through rituals such as sermon scenes of the Buddha. On the other hand, it was combined with Buddhist masses for the dead(追薦) from the mid-Joseon Dynasty and performed alongside with Buddhist teachings and prayers for the dead. Taking into account the seven-day Suryukjae, however, Yeongsanjae was performed daily during the day and mainly dealt with Buddhist teachings, while Buddhist masses for the dead were included when Yeongsanjae was performed independently.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.196-207
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• 2019

This study was carried out to investigate the effects of C. japonica, D. morbifera, D. macropodum, I. anisatum, Q. glauca and R. indica To investigate the photosynthetic ability, chlorophyll content, chlorophyll fluorescence analysis, and physiological environmental. The photosynthetic rate, cancer respiration rate, stomatal conductance, and rate of evaporation tended to decrease as a result of drying stress in the no-water condition for 28 days. I. anisatum, Q. glauca and R. indica showed a low rate of less than 40% until 28 days of no-treatment. The total chlorophyll contents were decreased in the order of D. macropodum> D. morbifera> C. japonica> Q. glauca> M. thunbergii> R. indica> I. anisatum. Chlorophyll fluorescence analysis showed that there was no change in the qP, but after 28 days no $Fv/F_m$, $F_o$, $R_{fd}$, $NPQ_{_-LSS}$ can be a useful indicator for quantitative estimation within a short period of time with a marked reduction rate of PSII quantum yield ${\Phi}PSII$ in the rectified state by continuous light during the nominal adaptation period. In the case of I. anisatum, Q. glauca and R. indica If water management can be carried out at intervals, it may be possible to plant trees in trees and landscape trees.

• Tunnel and Underground Space
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• v.29 no.4
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• pp.230-242
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• 2019

While various automatic rock fracture survey methods have been researched, the evaluation of the accuracy of these methods raises issues due to the absence of a metric which fully expresses the similarity between automatic and manual fracture maps. Therefore, this paper proposes a geometry similarity metric which is especially designed to determine the overall similarity of fracture maps and to evaluate the accuracy of rock fracture survey methods by a single number. The proposed metric, Scanline Intersection Similarity (SIS), is derived by conducting a large number of scanline surveys upon two fracture maps using Python code. By comparing the frequency of intersections over a large number of scanlines, SIS is able to express the overall similarity between two fracture maps. The proposed metric was compared with Intersection Over Union (IoU) which is a widely used evaluation metric in computer vision. Results showed that IoU is inappropriate for evaluating the geometry similarity of fracture maps because it is overly sensitive to minor geometry differences of thin elongated objects. The proposed metric, on the other hand, reflected macro-geometry differences rather than micro-geometry differences, showing good agreement with human perception. The metric was further applied to evaluate the accuracy of a deep learning-based automatic fracture surveying method which resulted as 0.674 (SIS). However, the proposed metric is currently limited to 2D fracture maps and requires comparison with rock joint parameters such as RQD.

• Tunnel and Underground Space
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• v.32 no.6
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• pp.464-477
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• 2022

DFN (discrete fracture network) models that take account of spatial variability and correlation between rock fractures have been demanded for analysis of fractured rock mass behavior for wide areas with high reliability, such as that of underground nuclear waste repositories. In this regard, this report describes the spatial distribution characteristics of fracture networks, and the DFN modeling methodologies that aim to represent such characteristics. DFN modeling methods have been proposed to represent the spatial variability of rock fractures by defining fracture domains (Darcel et al., 2013) and the spatial correlation among fractures by genetic modeling techniques that imitate fracture growth processes (Davy et al., 2013, Libby et al., 2019, Lavoine et al., 2020).These methods, however, require further research for their application to field surveys and for modeling in-situ rock fracture networks.

• Journal of Korean Society of Forest Science
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• v.111 no.3
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• pp.394-404
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• 2022

This study was conducted to optimize the amount of drip irrigation for Prunus×yedoensis Matsum., one of the major medium-sized landscaping trees used mainly for streetscapes and as ornamentals. The experiment was conducted in a container nursery, where we assessed the growth and physiological characteristics of 4- and 8-year-old seedlings watered at different rates (x) by a drip irrigation system. The relative growth rates (based on height and root collar diameter (RCD) measurements) were highest at 288 and 416 L/year/tree for the 4- and 8-year-old containerized seedlings, respectively. These age and treatment combinations also produced significantly different dry weight and seedling quality index values, indicating good growth. The two age groups had significantly different total root lengths, root diameters, and root volumes under these respective irrigation treatments. In addition, the 4-year-old containerized seedlings irrigated at 288 L/year/tree and the 8-year-old containerized seedlings irrigated at 416 L/year/tree had the highest activations in their chlorophyll contents. Overall, the results (differences in irrigation amounts affect the seedlings morphological relative growth, biomass growth, seedling quality, and physiological reaction) indicate that the optimal irrigation amounts for container-grown Prunus×yedoensis are 288 L/year/tree for 4-year-old (RCD class, 3cm) and 416 L/year/tree for 8-year-old (RCD class, 7 cm) containerized seedlings.