• The Bulletin of The Korean Astronomical Society
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• v.41 no.1
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• pp.81.2-81.2
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• 2016

Many signals in the nature have power-law behaviors, namely they are "scale-free". The method of detrended fluctuation analysis (DFA), as one of the popular methods (e.g., Rescaled range analysis and Spectral analysis) for determining scale-free nature of time series, has a very important advantage that the DFA can be applied to both stationary and non-stationary signals. The analysis of time series using the DFA has been broadly used in physiology, finance, hydrology, meteorology, geology, and so on. We performed the DFA of 16 Spaceweather HMI Active Region Patch (SHARP) parameters for 38 HMI Active Region Patches (HARPs) obtained by Solar Dynamics Observatory (SDO) from May 2010 to June 2014. The main results from this study are as follows. (1) The most of the time series data are non-stationary. (2) The DFA scaling exponents of "mean vertical current density" for 38 HARPs have a negative correlation coefficient (-0.41) with flare index. (3) The DFA scaling exponents of parameters such as "Sum of the absolute value of net currents per polarity", "Absolute value of the net current helicity", and "Mean photospheric excess magnetic energy density" for the most active HARPs having more than 10 major flares, have positive correlation coefficients (0.64, 0.59, and 0.53, respectively) with the ratio of "the number of CMEs associated with major flares" to "the number of major flares". Physical interpretations on our results will be discussed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.3
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• pp.37-43
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• 2001

The bleach efficiency between PY and YP bleaching of pulps, which were deinked in neutral (cellulase) and alkaline (NaOH, NaOH/${Na_2}{SiO_3}$) ranges, and were treated on kneader, was compared in this study. The brightness of pulps (84.8~88.4% ISO) which were deinked in alkaline or neutral ranges increased up to 88.4%~88.8% ISO after PY or YP bleaching. There was no difference in the brightness between PY and YP bleaching. And the dirt count of bleached pulps was similar each other at the range of 17~38 ppm. The tensile index of bleached pulps was slightly higher in PY bleaching than those in YP bleaching. While with the treatment of kneading, the brightness and dirt count decreased remarkably compared to those of no-kneading. However, the sharp difference in the brightnesses or in dirt count of bleached pulps decreased after bleaching. The brightness of bleached pulps at YP stages was only numberically higher than those at PY stages without regard to the treatment of kneading. Therefore, in the case of the neutral deinkiing process, the conversion of PY bleaching stages to YP bleaching stages was profitable to water loop system, and was harmless in the aspect of the bleach efficiency.

• Archives of Craniofacial Surgery
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• v.20 no.2
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• pp.139-143
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• 2019

Here we report a case of a focal atypical proliferative nodule (PN) arising from a congenital melanocytic nevus (CMN). Diagnosis was challenging because it had both benign and malignant clinical features. Unusual histopathology, immunohistochemistry, and intraoperative findings of this atypical PN are discussed. A 5-year-old girl was admitted for a congenital $5{\times}5cm$ sized scalp mass. This hemangioma-like soft mass showed biphasic characteristics such as a slow, gradual, and benign increase in size but worrisome dural invasion with cranial bone defect. We removed the scalp mass with clear resection margins. Interoperatively, we found that the cranial bone defect had already filled. Histopathologic examination showed CMN with focal atypical PN. The nodule showed sharp demarcation and cellular pleomorphism. However, in immunohistochemical study, Ki-67 proliferation index and expression levels of protein S-100 and Melan-A were very low. These were unusual findings of atypical PNs. Despite her worrisome preoperative radiologic features, she showed an indolent clinical course compatible with previously reported biologic behavior. The patient underwent follow-up inspection with magnetic resonance imaging every 6 months for up to 3 years. The nodule appeared to be stationary at the last visit.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.181-187
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• 1981

The changes in the chemical composition of yeast extracts during autolysis and their effect to the sensory quality were studied with baker's yeast, Saccharomyces cerevisiae. The amounts of extracted solids, proteins, amio-N. amino acids, especially glutamic acid, alanine and lysine, increased by the autolysis time up to 48 hrs. The results of sensory evaluation made by the multiple paired comparision test and Duncan's test indicated a significant difference is taste by the time of autolysis. In the profile test, the flavor character notes expressed by the panel were 17 different characters, 11 in aroma and 6 in taste. The character notes and the intensity of flavor changed with the time of autolysis. The sharp and beany flavor of the extracts which was autolyzed for 4 hours turned into meaty and worty flavor by 48 hours of autolysis. A proper arrangement of the flavor characters in the quantitative descriptive chart could provide a weighted value of the flavor grade. The aroma grade index and the taste grade index correlated to the amplitudes of the profile test.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.548-557
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• 2009

For centuries, forests have been a key component of rural livelihood. They are important both socially and economically in Nepal. Firewood and fodder are the basic forest products that are extracted daily or weekly basis in most of the rural areas in Nepal. In this study, a field survey of 100 households was conducted to examine the degree of forest dependency and forest resource availability, households' livelihood strategy and their relationship with forest dependency in Chitwan, Nepal. A household' response indexes were constructed, Gini coefficient, Head Count Poverty Index (HCI) and Poverty Gap Index (PGI) were calculated and one way ANOVA test was also performed for data analysis. Data revealed that 82/81% of all households were constantly used forest for firewood and fodder collection respectively while 42% of households were used forest or forest fringe for grazing. The Forest Product Availability Indexes (FPAI) showed a sharp decline of forest resources from 0.781 to 0.308 for a 20-yr time horizon while timber wood was noticeably lowered than the other products. Yet, about 33% of households were below the poverty threshold line with 0.0945 PGI. Income distribution among the household showed a lower Gini coefficient 0.25 than 0.37 of landholdings size. However, mean income was significantly varies with F-statistics=246.348 at P=0.05 between income groups (rich, medium and poor). The extraction of firewood, fodder and other forest products were significantly different between the income group with F-statistics=16.480, 19.930, 29.956 at P=0.05 respectively. Similarly, landholdings size and education were also significantly different between the income groups with F-statistics=4.333, 5.981 at P=0.05 respectively. These findings suggested that income status of households was the major indicator of forest dependency while poor and medium groups were highly dependent on the forests for firewood, fodder and other products. Forest dependency still remains high and the availability of forest products that can be extracted from the remaining forestlands is decreasing. The high dependency of households on forest coupled with other socioeconomic attributes like education, poverty, small landholders and so on were possibly caused the forest degradation in Chitwan.Therefore, policy must be directed towards the poor livelihood supporting agenda that may enhance the financial conditions of rural households while it could reduce the degree of forest dependency inspired with other income generating activities in due course.

• Journal of Korea Water Resources Association
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• v.56 no.12
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• pp.883-893
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• 2023

While South Korea's dependence on imported grains is very high, droughts impacts from exporting countries have been overlooked. Using the Evaporative Stress Index (ESI), this study globally analyzed frequency, extent, and long-term trends of agricultural droughts and their relation to natural oscillations and global crop prices. Results showed that global-scale correlations were found between ESI and soil moisture anomalies, and they were particularly strong in crop cultivation areas. The high correlations in crop cultivation areas imply a strong land-atmosphere coupling, which can lead to relatively large yield losses with a minor soil moisture deficits. ESI showed a clear decreasing trend in crop cultivation areas from 1991 to 2022, and this trend may continue due to global warming. The sharp increases in the grain prices in 2012 and 2022 were likely related to increased drought areas in major grain-exporting countries, and they seemed to elevate South Korea's producer price index. This study suggests the need for drought risk management for grain-exporting countries to reduce socioeconomic impacts in South Korea.

• Journal of Korean Biological Nursing Science
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• v.20 no.3
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• pp.187-195
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• 2018

Purpose: The purpose of this study was to identify associations among the sleep disturbance, fatigue, job stress, and blood and body fluid (BBF) exposure of shift-work nurses. Methods: A total of 299 shift-work nurses from two tertiary hospitals were enrolled in this study. We used the Insomnia Severity Index (ISI), and the Fatigue Severity Scale (FSS), and the Korean Occupational Stress Scale-Short Form (KOSS-SF) to evaluate sleep disturbance, fatigue, and job stress, respectively. The data were analyzed using t-test or chi-squared test and Logistic regression analysis using the SPSS 23.0 program. Results: We found that 43.8% of participants reported BBF exposure over the past year. Splash or exposure to broken skin of BBF were most frequent (56.9%), and followed by needlestick injuries (30.4%) and sharp injuries (12.8%). Age, hospital, working period, level of stress, sleep disturbance ($ISI{\geq}15$), fatigue (FSS $score{\geq}4$), job demand and organizational climate subset in KOSS-SF were significantly associated with BBF exposure in shift-work nurses. In multivariate analysis after adjusting age and hospital, the risk factors of BBF exposure in shift-work nurses were the level of stress and fatigue (FSS $score{\geq}4$). Conclusion: Fatigue and job stress were related to BBF exposure in shift-work nurses. Our results suggest that management of sleep disturbance, fatigue, and high job stress in shift-work nurses is needed to reduce risk of BBF exposure.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1996.04a
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• pp.208-208
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• 1996

In this work we investigated coupling of the m2 and m4 subtypes of muscarinic acetylcholine receptors expressed in chinese hamster ovary (CHO) cells to activation of neuronal nitric oxide synthase (nNOS). Stimulation of guanylate cyclase activity in detector neuroblastoma cells was used as an index of generation of nitric oxide (NO) in CHO cells. The agonist carbachol induced marked time and concentration-dependent enhancement of the activity of nNOS at m2 receptors. In sharp contrast, the response in CHO cells transfected with the m4 receptor gene was similar in magnitude to that observed in non-transfected cells, suggesting lack of significant coupling of m4 muscarinic receptors to NO signaling. This novel observation of functional divergence of the two muscarinic receptor subtypes at the level of activation of nNOS is quite intriguing, in light of the currently accepted dogma that they belong to the same functional class. This functional selectivity was not due to differential effects on intracellular Ca$\^$2+/ concentration, since activation of both subtypes of muscarinic receptors produced a comparable, albeit quite small, Ca$\^$2+/ signal. Taken together, our present data strongly suggest that the generally assumed functional equivalence of m2 and m4 muscarinic receptors should be carefully reexamined. These data also suggest the presence of alternate mechanisms of activation of nNOS, which might be operative in the absence of large changes in the concentration of cellular Ca$\^$2+/. The latter mechanisms are expected to be activated by m2, but not m4 muscarinic receptors. Both sets of findings are quits important in regards to refining the functional classification of muscarinic receptor subtypes and the cellular mechanisms of activation of NOS.

• Journal of Conservation Science
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• v.30 no.4
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• pp.365-372
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• 2014

The purpose of the present study is to determine the species of red and green pigments used on paintings of Korean temples and also to compare the two pigments according to the particle characteristics. The component analysis shows that the red pigment consists of cinnabar, hematite, and minium and the green pigment are composed of atacamite, celadonite, and malachite. The result suggests that mixture of various pigments were applied to the painting. When it comes to the particle characteristics, there are various hedral or anhedral shapes such as sharp, long, angular, and platy shapes even in the same cinnabar. In addition, the green pigment also shows a similar pattern with those of the red pigment. Up to now, an identification of minerals has been relied on examination of component and crystal shape. However, it is notable that using form related characteristics can be a better and useful method not only for categorization of pigments which are similar in terms of color and species but also specific index.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.7
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• pp.693-700
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• 2016

It is important that we can calculate the order of non-supersingular elliptic curves with large prime factors over the finite field GF(q) to guarantee the security of public key cryptosystems based on discrete logarithm problem(DLP). Schoof algorithm, however, which is used to calculate the order of the non-supersingular elliptic curves currently is so complicated that many papers are appeared recently to update the algorithm. To avoid Schoof algorithm, in this paper, we propose an algorithm to calculate orders of elliptic curves over finite composite fields of the forms $GF(2^m)=GF(2^{rs})=GF((2^r)^s)$ using Weil's theorem. Implementing the program based on the proposed algorithm, we find a efficient non-supersingular elliptic curve over the finite composite field $GF(2^5)^{31})$ of the order larger than $10^{40}$ with prime factor larger than $10^{40}$ using the elliptic curve $E(GF(2^5))$ of the order 36.