• Title/Summary/Keyword: 저경도

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Future Projections of Köppen Climate Shifts in the Asia Regions Using A2 Scenario (A2 시나리오를 이용한 아시아 지역 기후대의 변화 전망)

  • Shin, Sang Hoon;Bae, Deg Hyo
    • Journal of Korea Water Resources Association
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    • v.46 no.3
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    • pp.253-265
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    • 2013
  • The objective of this study is to analyse the current climate zone applied by K$\ddot{o}$ppen climate classification and the future climate zone projected by the A2 scenario in Asia regions. The spatial and temporal variations of precipitation and temperature were also analyzed. As regards to the result of analysis on the variation of climate factor, temperature and precipitation will be increasing $4.0^{\circ}C$ and 12% respectively in the 2080s comparing with the reference period (1991~2010). Spatially, the range of temperature increase on the high latitude area is higher than that on the low latitude area. The precipitation will be increasing averagely in the overall area, but the spatial unequal distribution of precipitation will be intensified. At the result of the future climate zone, the area of warm climates will be increasing while the area of cold climates will be decreasing. In 2080s, the temperature will be increasing as much as 7.2% and 1.9% on the Tropical climates and Arid climates respectively, but it will be decreasing as -2.4%, -4.9% and -1.8% on the Warm temperate climates, Cold climates and Polar climates respectively. Furthermore, the part of Savannah climates and Desert climates will be mostly increasing. It is mainly caused by the temperature increase and desertification impact according to global warming.

A Study on the Performance Improvement of ta-C Thin Films Coating on Tungsten Carbide(WC) Surface for Aspherical Glass Lens by FCVA Method Compared with Ir-Re coating (Ir-RE 코팅 대비 자장여과필터방식을 이용한 비구면 유리 렌즈용 초경합금(WC)표면의 ta-C 박막 코팅 성능 개선 연구)

  • Jung, Kyung-Seo;Kim, Seung-Hee
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.27-36
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    • 2019
  • The demand for a low dispersion lens with a small refractive index and a high refractive index is increasing, and accordingly, there is an increasing need for a releasable protective film with high heat resistance and abrasion resistance. On the other hand, the optical industry has not yet established a clear standard for the manufacturing process and quality standards for mold-releasing protective films used in aspheric glass lens molding. Optical lens manufacturers treat this technology as proprietary information. In this study, an experiment was conducted regarding the optimization of ion etching, magnetron, and arc current at each source and filter part, and bias voltage in FCVA (filtered cathode vacuum arc)-based Ta-C thin film coatings. This study found that compared to iridium-rhenium alloy thin film sputtering products, the coating conditions were improved by approximately 50%, 20%, and 40% in terms of thickness, hardness, and adhesive strength of the film, respectively. The thin-film coating process proposed in this study is expected to contribute significantly to the development and utilization of glass lenses, which will help enhance the minimum mechanical properties and quality of the mold-release thin film layer required for glass mold surface forming technology.

The Characteristics of Energy Distribution to Arc Length and Hydrogen Mixing in GTA Welding (GTA 용접에서 아크 길이와 수소 혼합에 따른 에너지분포 특성)

  • Oh, Dong-Soo;Baek, Sang-Yeob;Lee, Chil-Soon;Hwang, Dong-Soo;Ham, Hyo-Sik;Park, Kyung-Do;Jung, Yun-Ho;Cho, Sang-Myung
    • Proceedings of the KWS Conference
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    • 2009.11a
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    • pp.30-30
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    • 2009
  • GTA 용접에서 용입, 용접부의 크기와 형상이 형성되는 아크 물리학적 현상을 이해함에 있어서 에너지 분포특성은 매우 중요한 인자이다. GTA 용접에서 아크 길이의 변화와 사용된 실드 가스 종류에 따라 음극인 텅스텐 전극 팁의 아크 루트 직경에 큰 변화를 주며, 양극인 모재 쪽의 에너지 분포에 영향을 미치며 된다. 기존의 연구자들은 저전류나 중전류 영역의 GTA 용접에서 텅스텐 전극의 선단각과 용입 형태와 의 관계를 plasma 기류 등에 의해 고찰하거나, 최대 아크압력에 미치는 전극형상의 영향에 대하여 연구하였다. 용접부에 작용하는 아크 압력의 분포는 결국 운동 에너지의 분포이다. 기존의 연구자들에 비하여 보다 간편한 실험을 통하여 양극 모재위의 아크 압력에 의한 에너지 분포특성을 규명하는 연구가 필요하다. 본 연구의 목적은 GTA 용접의 용접전류 100A~200A 영역에서 아크 길이 변화와 Ar 가스에 $H_2$ 혼합에 따른 측정된 아크 압력으로부터 기존연구자들의 아크 물리학적 결과들을 활용하여 양극 모재 위에 작용하는 전류밀도 분포를 유도하는 것이다. GTA 용접에서 아크 길이의 변화와 Ar 가스에 $H_2$ 혼합은 아크 압력분포에 큰 영향을 미치며, 이에 따라 에너지 분포특성에 많은 영향을 미친다. 아크 길이가 증가함에 따라 Ar가스와 $H_2$ 혼합가스의 에너지 분포는 감소하였고, Ar가스에 $H_2$ 혼합에 의해 아크 에너지가 증가하여 용입형상에 큰 영향을 미칠 것으로 판단된다. 이에 대한 연구는 향후 GTA 용접 응용분야 확대 적용될 것이며, 아크 물리학 연구에 기초적이고 아주 중요한 과학적인 자료가 될 것으로 판단된다.

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Changes in the Physicochemical Properties of Korean rice cake by the Addition of Gelatinized Rice flour (알파미분 첨가에 따른 흰떡의 이화학적 특성변화)

  • Lee, Chang-Ho;Han, Ouk;Kum, Jun-Seok;Bak, Kyoung-Huk;Yoo, Byong-Kyu
    • Journal of the Korean Society of Food Culture
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    • v.10 no.2
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    • pp.101-106
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    • 1995
  • The effects of ${\alpha}-rice$ flour on the physicochemical properties of Korean rice cake were investigated. Before cooking, the degree of gelatinization of rice cake without ${\alpha}-rice$ flour was 5.75%, but 16% for adding ${\alpha}-rice$ flour. After cooking, the degree of gelatinization of rice cake were increased from 52% to 85% by adding ${\alpha}-rice$ flour. The L value of rice cake with ${\alpha}-rice$ flour increased, but there was no significant difference in L value between samples. The hardness of rice cake before and after cooking were increased by adding ${\alpha}-rice$ flour whereas after frozen stoarge there was no apparent effect on the color values of rice cake. The water absorption ratio of rice cakes during cooking were increased by addition of ${\alpha}-rice$ flour. Scanning electron photomicrographs revealed that the rice cake with ${\alpha}-rice$ flour has more porous structure with rapid rehydration.

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Effect of Glue Plant(Codium Fragile) on Physicochemical Characteristics of Dongchimi During Fermentation (청각채가 동치미의 발효 중 이화학적 특성에 미치는 영향)

  • Park, Bock-Hee;Cho, Hee-Sook
    • Journal of the Korean Society of Food Culture
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    • v.20 no.5
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    • pp.508-515
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    • 2005
  • The effect of glue plant(Codium fragile) on the Dongchimi fermentation was investigated by measuring physicochemical properties during fermentation at $10^{\circ}C$. Dongchimi was prepared with various levels(0, 0.5, 1.0 and 1.5%) of glue plant(Codium fragile). The pH of Dongchimi decreased slowly in all samples during fermentation. Total acidity of Dongchimi increased gradually during fermentation and total acidity of Dongchimi with glue plant(Codium fragile) was higher than that of control. Redox potentials decreased until 30 days of fermentation but increased thereafter. Reducing sugar content increased in the initial stage of the fermentation periods, and then decreased gradually. The reducing sugar content of Dongchimi with glue plant(Codium fragile) was higher than that of control. The content of total vitamin C was much higher in dongchimi with glue plant(Codium fragile). In color measurement, lightness value decreased gradually. However, redness and yellowness values increased gradually during fermentation but decreased thereafter. The content of hot water soluble pectin(HWSP) decreased as the fermentation proceeded, but the content of hydrochloric acid soluble pectin(HClSP) and sodium hexametaphosphate soluble pectin(NaSP) increased.

Effects of Gamma Irradiation and Methyl Bromide Fumigation on Quarantine Pest and Physical Quality of Apples (감마선과 methyl bromide 처리가 사과의 검역해충 및 물리적 품질에 미치는 영향)

  • Kang, Ho-Jin;Kwon, Yong-Jung;Byun, Myung-Woo;Kim, Hyun-Ku;Chung, Hun-Sik;Choi, Jong-Uook;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.35 no.5
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    • pp.783-790
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    • 2003
  • Tetranychus urticae Koch and Panonychus ulmi Koch were identified as quarantine pests in apple samples and were controlled soon after the commercial treatment of methyl bromide (MeBr) and with irradiation doses $(0.5{\sim}3kGy)$ after irradiation. The physical qualities of apples, such as rotting, withering, weight changes, hardness, and color, were apparently affected by MeBr. Furthermore, more than 2 kGy irradiation resulted from the lapse of storage time. Associated with the physical qualities of stored apples, irradiation and fumigation for quarantine purposes were more adequate after 40 days of storage at $0{\pm}1^{\circ}C\;(85{\pm}2%\;RH)$ immediately following harvest, rather than soon after harvest. Less than 1 kGy irradiation, based on its accumulated control effect on pests, can potentially be applied as a quarantine procedure without causing significant changes in the physical qualities of fresh apples, in contrast to MeBr.

Quality Characteristics of Yanggaeng Added with Tomato Powder (토마토 가루를 첨가한 양갱의 품질특성)

  • Kim, Kyoung-Hee;Kim, Young Shik;Koh, Jong-Ho;Hong, Min-Seo;Yook, Hong-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.7
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    • pp.1042-1047
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    • 2014
  • This study examined the quality characteristics of Yanggaeng added with tomato powder (0, 5, 10, 15, and 20%) and oligosaccharides instead of red beans and sugar. The moisture content of tomato Yanggaeng was 45.89~33.64% and was highest in the control group. The pH ranged 3.96~6.24 and significant decreased with the addition of tomato powder. Hunter's color value, lightness (L value) were the highest in Yanggaeng added with 20% tomato powder. Redness (a value) increased with tomato powder content, except for 20% tomato powder. Yellowness (b value) significantly increased with tomato powder content (P<0.05) but decreased with 20% tomato powder. In the texture profile analysis, hardness, cohesiveness, gumminess, and chewiness significantly decreased (P<0.05) with the addition of tomato powder. Total soluble solid content ($^{\circ}Brix$) was the highest (5.16) in the control group, whereas that of tomato Yanggaeng ranged 4.46~4.92 and significantly decreased (P<0.05) with the addition of tomato powder. The antioxidative activity based on 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of Yanggaeng increased with the concentration of tomato powder, although those of Yanggaeng added with 15% and 20% tomato powder were not significantly different (P<0.05). Yanggaeng added with 5 and 10% tomato powder showed acceptable sensory properties, including color, flavor, sweet taste, sour taste, and overall quality. In terms of sensory evaluation and antioxidant activity, the results show that Yanggaeng added with 10% tomato powder was the best, but more research should be conducted in order to improve sensory acceptability.

Studies on the Utilization of Persimmons -(Part 1) Effect of Carton Dioxide Treatment on the Removal of Astringency- (감의 이용(利用)에 관(關)한 연구(硏究) -제1보(第一報) 탄산(炭酸)가스처리(處理)가 탈삽(脫澁)에 미치는 영향(影響)-)

  • Seu, Ohn-Soo;Sohn, Tae-Hwa
    • Applied Biological Chemistry
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    • v.19 no.2
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    • pp.93-98
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    • 1976
  • The experiment was made to investigate concentrations of $CO_2\;and\;O_2$ in the removal of astringency of persimmon fruits and to study the changes of total, reducing sugar and hardness during the removal of astringency. 1. During the removal of astringency of persimmon fruits, channel of tannin content showed the rapid decrease in high concentration of $CO_2$ and the gradual decrease in low concentration of $CO_2$. 2. Concentration of oxygen did not show effect on the removal of astringency at high concentration of $CO_2$ but at low concentration of $CO_2$ in Chungdo-Bansi. 3. Optimal concentration of the removal of astringency was $60{\sim}70%,\;CO_2$ and $6{\sim}8%\;O_2$ in Chungdo-Bansi and Sagoksi 4. In changes of sugar content total sugar was decreased and reducing sugar was increased.

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Various Factors giving impacts on the Visual Impairment in schoolchildren (초등학생들의 시력장애에 영향을 미치는 요인)

  • Kim, Jeoung Hee
    • Journal of Korean Ophthalmic Optics Society
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    • v.5 no.2
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    • pp.79-85
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    • 2000
  • This study was investigated the refractive state and the analysis of ametropic frequency among schoolchildren who were the three grade in W elementary school in Suwon. Total 488eye (244 persons) were examined by the trial-lens set and the questionary. Through Trial-Lens set verification, several factors related to ametropic frequency were obtained as the following. Among the 244 persons, the students who wear spectacles or need to wear spectacles were 27.3%, among the 27.3% students, the students who have low visual acuity below 0.3 were 6.3%. The ametropia eyes among the total eyes were 27.3%. Among ametropic eyes, myopia and hyperopia were 25.4% and 1.9%. Among the total ametropic errors were low refractive error were 71.4%, and middle refractive error were 28.6%. In ratio myopic frequency, it was statistically related to the refractive errors with the environments factors such as reading distance & habits, T.V watching distance. Among the students belonged to below 0.7 visual acuity, the wear spectacles students were 63.3%. The ratio of anisometropia was 3.4%.

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Comparison of Immunohistochemical Expression of CBP(cAMP-responsive Element Binding Protein) Transcriptional Co-activator between Premalignant Lesions and Squamous Cell Carcinomas in the Lungs (전암성 폐병변 및 편평상피세포폐암 조직에서 CBP(cAMP-responsive Ele-ment Binding Protein) 전사 공동 활성인자의 면역조직화학적 발현양상의 비교)

  • Shin, Jong Wook;Kim, Jin Soo;Kim, Mi Kyung
    • Tuberculosis and Respiratory Diseases
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    • v.63 no.2
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    • pp.165-172
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    • 2007
  • Background: The pathogenesis of lung cancer includes the accumulation of multiple genetic abnormalities. The CREB-binding protein(CBP) is one of several transcriptional co-activators among various sequence-specific DNA-binding transcription factors. CBP is involved in a wide range of cellular activities, such as DNA repair, cell growth, differentiation, and apoptosis that are suspected of contributing to tumorigenesis. The goal of this study was to evaluate CBP expression in a series of human lung tissues containing normal epithelium, premalignant lesions(hyperplasia and dysplasia) and squamous cell carcinomas. Materials and Methods: Immunohistochemical staining was performed on formalin-fixed paraffin-embedded sections by use of a monoclonal anti-CBP antibody. CBP expression was compared in samples from 120 patients with premalignant and malignant histological types including 20 metaplastic specimens, 40 dysplastic specimens, and 60 squamous cell carcinomas in the lung. Results: CBP expression was seen in 35% (7/20) of the metaplastic specimens. 65% (26/40) of the dysplastic specimens, and 70% (42/60) of the squamous cell carcinomas (p<0.05). According to celluar atypism, CBP expression was 50% (10/20) of the low-grade dysplastic specimens and 80% (16/20) of the high-grade dysplastic specimens(p <0.01). By cellular differentiation, CBP expression was seen in 95% (19/20) of the well differentiated squamous cell carcinomas, 85% (17/20) of the moderately differentiated carcinomas and 30% (6/20) of the poorly differentiated lesions (p <0.05). Conclusion: These results suggest that CBP may have an important role in malignant transformation of precancerous lung lesions and may be a marker for malignancy.