• 생약학회지
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• 제53권2호
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• pp.111-118
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• 2022

Chestnut honey is a sweet dark-colored honey with a distinct bitter aftertaste. It contains numerous phenolic compounds and alkaloids and is noted for its antioxidant and anti-inflammatory activities. However, it has been established that there are differences in the composition and activity of chestnut honey constituents depending on the region of origin, the sources of which warrant further research. In this study, we analyzed the kynurenic acid (KA) contents in chestnut honey produced in nine different regions in Korea, using high-performance liquid chromatography in conjunction with ultraviolet detection, and validated the analytical method developed. Use of a reverse-phase column and detection at a wavelength of 240 nm were found to be optimal for the detection of KA. Similar evaluation of an optimal method for extracting KA from chestnut honey revealed that extraction using 10% EtOH at 20 times the sample volume over a 6 h period was the most suitable for obtaining a high content of KA. Among the nine regional chestnut honeys assessed, KA content was found to be highest in the "Gongju" sample (1.14 mg/g), followed by that in the "Cheongdo" and "Damyang" samples. Validation of the KA analytical method revealed a good analyte linearity, with a correlation coefficient (r²) of 0.9995, an accuracy of between 92.37% and 107.35%, and good precision (RSD ≤ 1.05%). Our findings in this study, based on a validated quantitative analytical method for KA, could make an important contribution to establishing a data profiling procedure for characterizing chestnut honeys produced in different regions, and may also provide basic data for the identification of functional honey.

• 치과방사선
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• 제27권2호
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• pp.83-90
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• 1997

This study was performed to demonstrate the effect of linear or nonlinear contrast enhancement on subtraction images. Three different textures were radiograped on dental film. The first radiograph was taken without the presence of an object. the second, which showed trabucular bone, was taken of the molar area of a human. the third radiograph was taken of the coronal part of molars. Each film was digitized into a 1312 x 1024 pixel x 8 bit depth matrix by means of a Nikon 35 mm film scanner(LS-3510AF, Japan) with fixed gain and internal dark current correction to maintain constant illumination. The scanner was interfaced to a Macintosh Le ill computer(Apple Computer, Charlotte, N.C) This resulted in three pairs of images, including different textures-plain, bone and enamel. Digital regular, linearly and nonlinearly enhanced subtraction was performed. Computer software was ,used to simulate lesions in the shape of a 2D-Gaussian curve on each of a pair of images. The each subtraction images were presented in a random sequence to two groups of 10 observers(students and dentists). ROC analysis was used to compare observer performance. The following results were obtained ; 1. All of LCE subtraction, equalized subtraction and regular subtraction images of plain texture were diagnosed the best by far. 2. The data revealed a siginificant LCE effect in both the student group and the expert group. 3. Clinical expertise was a helphul factor for the observers in this study.

• Journal of Ecology and Environment
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• 제38권4호
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• pp.647-654
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• 2015

A prostrate species of Codium (Bryopsidales, Chlorophyta) was collected from Daejin on the eastern coast of Korea. This alga is morphologically characterized by a prostrate, adherent or pulvinate, dark green thallus that is tightly attached to substratum. The utricles are strongly grouped and cylindrical to slightly clavate. Their apex is rounded to capitated, and it frequently has an alveolate ornament. Hair scars are found in the upper portion of the utricle. The gametangia grow on a short pedicel in the upper part of the utricle. In the phylogenetic tree based on molecular data, this alga is placed in the same clade as C. mozambiquense in UPGMA analysis, and nests in a sister clade of C. lucasii subsp. capense and C. mozambiquense in ML and NJ analyses. However, the genetic distance between the sequences of the Korean alga and the two species is 1.3-1.9%, while that between the Korean alga and C. lucasii from Japan is 1.1% within intraspecific range. The divergence value between the Korean alga and C. lucasii from the type locality (Australia) is 2.7% considered to be interspecific range. As based on this genetic divergence value, the Korean alga together with Japanese C. lucasii can be separated from genuine C. lucasii from the type locality. However, the Korean alga is identified as C. lucasii until those entities are morphologically characterized in species level. This is the first record of C. lucasii in Korea

• 한국정보시스템학회지:정보시스템연구
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• 제24권2호
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• pp.53-72
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• 2015

Purpose The purpose of this study was to investigate the factors affecting the users' stress and using reluctant intention to use social network service(SNS). This study especially focused on stress of SNSs' user. Because SNS has led to negative effects such as invasion of privacy, addiction and social overload recently. In addition, adverse effects of SNS had caused SNSs' user to feel stress and fatigue. Design/methodology/approach This study developed hypotheses to empirically examine the factors that affect SNS users' stress and using reluctant intention. In order to verify research hypotheses, this study collected data from 362 users who currently use the SNS in Korea. Further, we used the smartPLS analysis. Findings The results of this study are as follows; First, reputation perception, unwanted relation burden, privacy concern, information overload and interaction overload had a significant positive effect on SNS users' stress. But international influence had no significant positive effect on SNS users' stress. Second, SNS users' stress had a significant positive effect on using reluctant intention. The results of this study provides theoretical foundations on the research for dark side of SNS and implies that SNS providers are in need of exerting an effort to minimize the negative aspects.

• 환경영향평가
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• 제10권1호
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• pp.1-8
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• 2001

Detection of red tides by satellite remote sensing can be done either by detecting enhanced level of chlorophyll pigment or by detecting changes in the spectral composition of pixels. Using chlorophyll concentration, however, is not effective currently due to the facts: 1) Chlorophyll-a is a universal pigment of phytoplankton, and 2) no accurate algorithm for chlorophyll in case 2 water is available yet. Here, red band algorithm, classification and PCA (Principal Component Analysis) techniques were applied for detecting patches of Cochlodinium polykrikoides red tides which occurred in Korean waters in 1995. This dinoflagellate species appears dark red due to the characteristic pigments absorbing lights in the blue and green wavelength most effectively. In the satellite image, the brightness of red tide pixels in all the three visible bands were low making the detection difficult. Red band algorithm is not good for detecting the red tide because of reflectance of suspended sediments. For supervised classification, selecting training area was difficult, while unsupervised classification was not effective in delineating the patches from surrounding pixels. On the other hand, PCA gave a good qualitative discrimination on the distribution compared with actual observation.

• 한국콘텐츠학회논문지
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• 제14권2호
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• pp.364-375
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• 2014

본 연구는 자살시도 경험이 있는 남성알코올중독자의 삶의 전 과정을 통해 어떤 경험을 하게 되는지 그 본질적 의미를 심층적으로 이해하고자 하였다. 현상학적 연구방법을 활용하였으며, Colaizzi의 분석방법을 통해 연구대상자의 고유경험을 깊이 있게 기술하였다. 자살시도 경험이 있는 남성알코올중독자의 삶의 경험의 본질적 구조는 총 12개의 주제와 5개의 주제묶음이 도출되었다. '심리 정서적 암흑의 굴레 지속하기', '인정하기 싫은 하찮은 자신과의 조우', '자살을 부추기는 방아쇠', '음주와 자살의 뿌리-원죄 같은 해결되지 않은 숙명과 함께 살아가기', '삶의 끈을 잡고 일어서기'이다. 이러한 연구결과를 바탕으로 자살시도 경험이 있는 알코올중독자를 위한 정신보건사회복지 실천적 개입방향을 제시하였다.

• 한국의류산업학회지
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• 제9권2호
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• pp.138-144
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• 2007

The purpose of this research was to compare the harmony of tone on tone coloration according to transformation of color area-ratio in shirt and necktie. The respondents were asked to evaluate 48 stimuli of the shirt and necktie with the coloration of the shirt/necktie, the necktie/shirt was separately compounded to be 4 tones such as vivid, light, dull, dark. The subjects were 288 female undergraduate students. The data was analyzed by using SPSS program. Analysis methods were ANOVA, LSD test and t-test. The results of each can be summerized as follows. As to the red, combination of v-lt made a difference in the harmony of coloration according to the transformation of color area-ratio. As to the blue, combination of v-lt, v-dk, lt-d made a difference in the harmony of coloration according to the transformation of color area-ratio. As to the purple, v-lt, v-d was evaluated as harmonized coloration regardless of area-ratio by both male and female students. As to the green, v-lt, lt-d was evaluated as harmonized coloration regardless of area-ratio by both male and female students.

• Journal of Plant Biology
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• 제34권4호
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• pp.303-309
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• 1991

Limitation of photosynthesis in detached Chinese cabbage (Brassica campestris L.) leaves was induced by feeding of mannose (25 mM) for 12 h in the light, and changes in the basic thylakoid functions under this condition were investigated. The acid soluble phosphate contend and CO2 uptake rate was decreased by 66% and 67%, respectively. However, the starch content was increased by 24% compared to those of controls. From the fast induction curves of chlorophyll fluorescence, dark level fluorescence (Fo) slightly increased while intermediate plateau fluorescence level (FI) to peak level fluorescence (Fp) transient was significantly decreased with a slight decrease in the Fo-to-FI transient. This data means that reduction of secondary electron acceptor of PSII (QB) might be more severely inhibited than that of primary electron acceptor of PSII (QA) by decrease in phosphate level. The strong decline of (Fv)m//Fm ratio suggests that efficiency of excitation energy capture by PSII was decreased markedly. The quenching of Fo (qO), an indicator of state transition, was also occurred over the slow induction kinetics of chlorophyll fluorescence. From quenching analysis, fluorescence was dominantly quenched by nonphotochemical quenchings (qE+qT). These results showed that the capture and transfer efficiency of excitation energy to PSII reaction center in thylakoid was decreased with the decline of leaf phosphate level, and that the state transition was occurred during the induction of photosynthesis under these conditions.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.92-95
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• 2008

The Geostationary Ocean Color Imager (GOCI) is under development to provide a monitoring of ocean-color around the Korean Peninsula from geostationary platforms. It is planned to be loaded on Communication, Ocean, and Meteorological Satellite (COMS) of Korea. The GOCI has been designed to provide multi-spectral data to detect, monitor, quantify, and predict short term changes of coastal ocean environment for marine science research and application purpose. The target area of GOCI observation covers sea area around the Korean Peninsula. Based on the nonlinear radiometric model, the GOCI calibration method has been derived. The radiometric model of GOCI has been validated through radiometric ground test. From this ground test result, GOCI radiometric model has been changed from second order to third order. In this paper, the radiometric test performed to evaluate the radiometric nonlinearity is described and the GOCI radiometric error propagation is analyzed. The GOCI radiometric calibration is based on onboard calibration devices; solar diffuser, DAMD (Diffuser Aging Monitoring Device). The radiometric model error due to the dark current nonlinearity is considered as a systematic error. Also the offset correction error due to gain/offset instability is considered. The radiometric accuracy depends mainly on the ground characterization accuracies of solar diffuser and DAMD.

• 한국주거학회논문집
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• 제14권6호
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• pp.95-104
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• 2003

The purpose of this study was to find out the actual condition of University student's use of colors and its favored colors in their rooms. This is to proffer basic data for the color planning of University student's rooms in the future. Questionnaires research method was conducted and 343 sample were selected. The analysis used spss program. The result was as follows； 1) At present, Y or Light tone of YR are mostly used for the floors of University student's rooms, white or Very pale tone of Y were used for walls and ceilings, YR or various tones were used for opening parts. 2) The degree of satisfaction of the color environment was 2.87 in average - ″a little dissatisfied″, more than half of the samples needed to change the color environment. 3) The favored color image of the students was regarded as ″warm, neat, tender, bright and light″ 4) In case of the favored colors of the essential parts, floors were Y or Pale tone of YR, walls were Very pale tone of Y, PB, B, RP. And Very pale tones of B, PB, Y, White for ceilings, Pale tones of YR, White, Dark Blue for opening parts were favored.