• 센서학회지
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• 제30권1호
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• pp.56-60
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• 2021

In this study, the relationship between the transmitted light intensity and full-width-at-half-maximum (FWHM) of a Fabry-Perot filter was investigated. The measured refractive indices and absorption coefficients of the fabricated thin films were applied to the Fabry-Perot filter via simulations using optical software. Although considerable research has been conducted on Fabry-Perot filters, this study focused on the usefulness of 4.26-㎛ infrared filtering in carbon dioxide detection. Optical analysis was performed considering the effects of the thickness, refractive indices, and number of thin films in a distributed Bragg reflector. Ultimately, a clear trade-off relationship was observed wherein the transmitted light intensity decreased as the number of multilayers increased; however, the FWHM was observed to be narrower.

• Journal of Korea Trade
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• 제26권5호
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• pp.23-38
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• 2022

Purpose - This research intends to find out whether R&D cost stickiness shows differentiated aspects depending on exports in Korea. A cost behavior that indicates a lower rate of costs decrease when sales decrease than the rate of costs increase when sales increase is called cost stickiness. This sticky cost behavior is caused by considering the adjusting costs. This study aims to empirically verify that R&D cost stickiness is greater in export firms than in non-export firms. We also investigate the effect of exports on R&D cost stickiness is nonlinear. Design/methodology - We obtain data for the analysis from Kis-Value and TS2000 from 2012 to 2020. This study tests for R&D cost stickiness of exports using the cost stickiness model developed by Anderson et al. (2003) that is used in a lot of prior literature. To explore the nonlinear behavior of R&D cost stickiness we include a quadratic term of exports in our model. Findings - The results of our analysis are as follows. First, we observed that R&D costs of export firms are more sticky than that of non-export firms. Our result indicated that export firms are less likely to reduce R&D costs in decreasing sales periods in preparation for future sales recovery. Second, our empirical evidence shows that export firms view R&D costs much favorably. However, we hypothesize that the effect of export intensity on R&D costs may not necessarily be linear. Our result shows the effect of exports intensity on R&D stickiness is thus nonlinear, forming a reverse U-shaped curve. When export intensity exceeds a certain threshold, the growth rate of R&D costs appears to be viewed negatively. Firms with relatively high export intensity do not support R&D costs, viewing them as taking away firms' resources from other more productive costs. On the contrary, those with export intensity under the threshold view R&D costs as beneficial and therefore promote further R&D costs when revenue decreases. Originality/value - The results of this research can contribute academically to the expansion of empirical research on R&D cost stickiness. R&D cost stickiness varies by industry. As a result of our research, the managers of export firms recognize the importance of R&D to lead innovation. We expected that this research contributes to further studies on R&D costs and cost stickiness. Second, this research has implications from a business perspectives. Our findings of export firms' R&D stickiness suggest that export firms' managers should consider keeping the stickiness of R&D when revenue decreases because it is essential for exporting firms to maintain their R&D stickiness to secure long-term competitiveness. R&D stickiness can be used on a practical basis to emphasize the need for continuous investment in exporting firms' R&D activities.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.124-124
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• 2003

Citrus canker is very important disease in international trade of citrus. The disease was usually take place from late of June, and severe middle of July to middle of August, though disease occurrence was affected by environmental conditions. In pathogenicity test, three varieties, orange, lemon and kiyomi among 7 varieties, were succeptible, two varieties, satsuma mandarin and iwasachi, intermediate resistant. On the other hand, shiranuhi and yuzu were resistant relatively. The pathogen, Xanthomonas axonopodis pv. citri, grew well in PD broth adjusted to pH 7.0 at 26$^{\circ}C$. It's growth was best in medium containing group of monosaccharide as a carbon source and group of ammonium as a nitrogen source. Tow isolates were resistant to streptomycin among 11 isolates isolated from diseased leaves in field in Jeju-Do. The streptomycin sensitives isolate was controlled by in greenhouse test. On the other hand, the resistant and sensitive isolates were controlled by treatment with copper sulfate, the control value is 88.7％ and 90.6％, respectively.

• 한국육종학회지
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• 제42권2호
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• pp.163-168
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• 2010

본 실험은 곡류 작물중에서 육종의 소재로써 많은 장점을 지닌 호밀을 Gimsa C-분염법과 FISH기법을 이용하여 구성이질 염색질과 5S와 18S-26S rRNA 유전자의 염색체상의 위치를 확인하고자 본 실험을 수행하였다. 그 결과를 요약하면 아래와 같다. 표지되었으며 2차협착으로 부수체가 존재하는 1번 염색체의 부수체의 말단과 5번 염색체의 중간에 표지되었고, 18S-26S rDNAs 유전자는 1개의 염색체에 표지되었으며 이 염색체는 2차협착으로 부수체가 존재하는 1번 염색체의 인 형성체 부위에 표지되었다. 1번 염색체에는 5S 와 18S-26S rDNAs 유전자가 표지되었고 5번 염섹체에는 5S rDNA 유전자만이 표지되었다.

• 한국염색가공학회지
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• 제26권2호
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• pp.71-78
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• 2014

This review paper is a state of the art report of the development of high performance nano-composites with carbon nanotube. We investigate the research and development (R&D) trends of high performance nano-composites with carbon nanotube by analyzing technical trends in research institutes and industry. We report the R&D and technology trends for the properties and applications of fabrication of hybrid composites with aligned carbon nanotubes, multifunctional fiber/carbon nanotube composites. We discuss the specific topics including unidirectional carbon nanotube, carbon nanotube forests, transfer-printing carbon nanotube technology, deposition of carbon nanotube by electrophoresis, vapor grown carbon fiber (VGCF), cup-stacked carbon nanotube, bucky paper and carbon nanotube yarns in this review paper.

• 전기전자학회논문지
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• 제26권2호
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• pp.329-332
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• 2022

본 논문에서는 ferroelectric(HfO₂)구조가 적용된 3D NAND flash memory의 parameter에 따른 lateral charge migration의 retention과 V_th를 분석하였다. P_s가 클수록 Program 시 ferroelectric에서 가능한 최대 polarization이 크기 때문에 초기 V_th는 P_s 25µC/cm² 보다 P_s 70µC/cm²에서 약 1.04V차이로 커진다. 또한 Program 이후 trap된 전자는 시간이 지남에 따라서 lateral charge migration이 발생한다. Program 이후 gate에 전압을 가하지 않고 ferroelectric은 polarization을 유지하기 때문에 P_s와 크게 관계없이 P_r이 클수록 polarization이 커지고 lateral charge migration에 의한 ∆V_th는 P_r 5µC/cm² 보다 P_r 50µC/cm²에서 약 1.54V차이로 작아진다.

• 한국생산제조학회지
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• 제26권3호
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• pp.278-284
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• 2017

Generally, classifiers have been used as machines to crush raw materials and classify suitable particle sizes in all industrial fields, such as food, chemical, and mineral. However, the technique for classifying micron-sized particles between 5 and $20{\mu}m$ is inferior. In particular, numerous experiments and considerable experiences are required to predict the particle size, because the classifier particle size is determined according to the internal flow. However, it is quite difficult to set the driving conditions so that the desired particle size can be classified only by experience and experimentation. Therefore, this study proposes a method of predicting the average particle size by employing multiphase flow analysis and the Taguchi method; this method is subsequently verified.

• Mycobiology
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• 제40권4호
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• pp.255-257
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• 2012

Among 80 types of yeast isolated from wild flowers in Daejeon, Korea, two species that have not yet been identified by phylogenetic analysis of the internal transcribed spacer-2 (ITS2) genes and 26S rDNA sequences were identified as Candida sp. 44-C-1 and Cryptococcus sp. 9-D-1. Neither of the newly identified species formed ascospores, while Candida sp. 44-C-1 formed pseudomycelium and Cryptococcus sp. 9-D-1 did not.

• Molecules and Cells
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• 제21권1호
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• pp.34-41
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• 2006

The neuronal localization of alpha-amino-3-hydroxyl-5-methyl-4-isoxazole propionic acid (AMPA) glutamate receptor (GluR) subunits is vital as they play key roles in the regulation of calcium permeability. We have examined the distribution of the calcium permeable AMPA glutamate receptor subunit GluR1 in the mouse visual cortex immunocytochemically. We compared this distribution to that of the calcium-binding proteins calbindin D28K, calretinin, and parvalbumin, and of GABA. The highest density of GluR1-immunoreactive (IR) neurons was found in layers II/III. Enucleation appeared to have no effect on the distribution of GluR1-IR neurons. The labeled neurons varied in morphology; the majority were round or oval and no pyramidal cells were labeled by the antibody. Two-color immunofluorescence revealed that 26.27%, 10.65%, and 40.31% of the GluR1-IR cells also contained, respectively, calbindin D28K, calretinin, and parvalbumin. 20.74% of the GluR1-IR neurons also expressed GABA. These results indicate that many neurons that express calcium-permeable GluR1 also express calcium binding proteins. They also demonstrate that one fifth of the GluR1-IR neurons in the mouse visual cortex are GABAergic interneurons.

• 대한지역사회영양학회지
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• 제19권1호
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• pp.12-26
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• 2014

The purpose of this study was to investigate the relationships among serum adiponectin, leptin and vitamin D concentrations and the metabolic syndrome in Korean farmers. 105 (26 males, 79 females) farmers (39~78 years, mean age $59.4{\pm}9.6$ years) in Gangwon - area were included in this study. Anthropometric measurements and biochemical blood analysis of subjects were carried out. The prevalence of obesity, abdominal obesity, hypertension, diabetes, hypertriglyceridemia, hypercholesterolemia and hyper LDL-cholesterolemia, metabolic syndrome were 51.9%, 65.7%, 49.5%, 15.3%, 17.3%, 13.5%, 11.5% and 40.9%, respectively. Serum adiponectin and leptin levels ($8.90{\mu}g/ml$ and 12.6 ng/ml) of females were significantly higher than those ($6.49{\mu}g/ml$ and 4.88 ng/ml) of males. But there was no significant difference in 25(OH)vitamin D concentration between males (15.4 ng/ml) and females (16.9 ng/ml). In the subjects with metabolic syndrome, the adiponectin levels were significantly lower and leptin levels were significantly higher than those of the subjects without metabolic syndrome. Serum adiponectin level had positive correlations with HDL-cholesterol level (r = 0.325, p < 0.001), but showed negative correlations with triglyceride and fasting blood glucose concentrations, body weight and waist/hip circumference ratio (r = -0.202 ~ -0.317, p < 0.05). Serum leptin and 25(OH)vitamin D concentrations were positively correlated with body fat (kg, %) and BMI, waist and hip circumferences (r = 0.244 ~ 0.682, p < 0.001). The results of this study suggested that adiponectin and leptin levels could be credible indices to predict chronic diseases in farmers. However, further research on vitamin D should be carried out considering another factors.