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Prediction of future hydrologic variables of Asia using RCP scenario and global hydrology model (RCP 시나리오 및 전지구 수문 모형을 활용한 아시아 미래 수문인자 예측)

  • Kim, Dawun;Kim, Daeun;Kang, Seok-koo;Choi, Minha
    • Journal of Korea Water Resources Association
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    • v.49 no.6
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    • pp.551-563
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    • 2016
  • According to the 4th and 5th assessment of the Intergovernmental Panel on Climate Change (IPCC), global climate has been rapidly changing because of the human activities since Industrial Revolution. The perceived changes were appeared strongly in temperature and concentration of carbon dioxide ($CO_2$). Global average temperature has increased about $0.74^{\circ}C$ over last 100 years (IPCC, 2007) and concentration of $CO_2$ is unprecedented in at least the last 800,000 years (IPCC, 2014). These phenomena influence precipitation, evapotranspiration and soil moisture which have an important role in hydrology, and that is the reason why there is a necessity to study climate change. In this study, Asia region was selected to simulate primary energy index from 1951 to 2100. To predict future climate change effect, Common Land Model (CLM) which is used for various fields across the world was employed. The forcing data was Representative Concentration Pathway (RCP) data which is the newest greenhouse gas emission scenario published in IPCC 5th assessment. Validation of net radiation ($R_n$), sensible heat flux (H), latent heat flux (LE) for historical period was performed with 5 flux tower site-data in the region of AsiaFlux and the monthly trends of simulation results were almost equaled to observation data. The simulation results for 2006-2100 showed almost stable net radiation, slightly decreasing sensible heat flux and quite increasing latent heat flux. Especially the uptrend for RCP 8.5 has been about doubled compared to RCP 4.5 and since late 2060s, variations of net radiation and sensible heat flux would be significantly risen becoming an extreme climate condition. In a follow-up study, a simulation for energy index and hydrological index under the detailed condition will be conducted with various scenario established from this study.

An Analysis of Thermal Comforts for Pedestrians by WBGT Measurement on the Urban Street Greens (도심 가로 녹음의 습구흑구온도(WBGT) 측정을 통한 보행자 열쾌적성 효과 분석)

  • Ahn, Tong-Mahn;Lee, Jae-Won;Kim, Bo-Ram;Yoon, Ho-Seon;Son, Seung-Woo;Choi, Yoo;Lee, Na-Rae;Lee, Ji-Young;Kim, Hae-Ryung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.41 no.3
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    • pp.22-30
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    • 2013
  • This study aims to measure the thermal comfort effects of urban street trees. As the usual dry bulb air temperature does not indicate properly how the average pedestrian feels the heat of a typical summer day under the strong sunshine, we adopted the Wet Bulb Globe Temperature(WBGT). WBGT involves black globe temperature to measure the direct radiation of sun beams on our bodies, for example our heads. We measured temperatures on very sunny and hot summer days, August 3, 4, and 7, 2012, on the urban streets of Seoul, Korea. Wet bulb, globe, and dry bulb temperatures were measured under direct sunlight from 1 O'clock to 5 O'clock pm. Globe and dry bulb temperatures were measured under street tree shades nearby during the same hours. Then the WBGTs were calculated with the formulae, one for sunny outdoor spaces, and the other for shaded outdoor spaces or indoor. The results are compared with the Korean Standards Association(KS A ISO 7243). The major findings were: 1) On very sunny and hot summer days in Seoul, street tree shades lower the WBGT about 1 to 4 degrees, 2) during the hours of 3 and 4 O'clock in the afternoon, the WBGT under the tree shades are about 3 to 4 degrees lower compared to those under sunshines(approx. 29 to 32 degrees respectively), 3) This difference makes a major thermal comfort for urban pedestrians because senior citizens or weak persons are recommended to move indoor, and even healthy people are recommended stop outdoor sports and take rests in the shades when WBGT is about 32. On the other hand, if the WBGT is around 29, or 3 degrees lower, slower walking, light works or sports are allowable, 4) On site questionnaire survey confirms the thermal comforts under the tree shades, and we even could not get survey subjects on the sunny parts of the sidewalks, 5) We strongly recommend change of guidelines for urban street trees from "one row of street trees on 6m~8m intervals" to "street trees to make continuous shades".

Forsythiae Fructus Induces VEGF Production via p38 MAPK Activation in Human Keratinocytes (각질형성세포에서 p38 MAPK 활성을 통한 연교의 VEGF 생성 효과)

  • Kim, Mi-Sun;Choi, Yun Ho;Park, Sun Gyoo;Lee, Cheon Koo;Lee, Sang Hwa
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.42 no.4
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    • pp.329-336
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    • 2016
  • Cutaneous microvasculature plays a critical role in age-associated skin changes. A considerable reduction of number and size of vessels has been observed in the upper dermis of elderly skin. Forsythiae fructus (FF), the dried fruit of plant Forsythia suspensa (F. suspensa), has been traditionally used as an herbal medicine to treat inflammatory diseases and bacterial diseases. However, its regulatory effect on angiogenic responses has not been elucidated in skin. Therefore, we analyzed secretory profiles upon treatment of FF extract using array designed to detect angiogenesis-associated mediators in human keratinocytes. Because keratinocyte-derived VEGF (vascular endothelial growth factor) has been regarded as a potent factor for new microvasculature under the epidermis, we further investigated the effect of FF extract on VEGF production. We observed that the VEGF expression of mRNA and protein level was increased by about 2 folds in a dose-dependent manner after FF extract treatment. In signaling experiments, FF extract induced rapid p38 MAPK activation within 5 min, and the activation was totally abrogated by pretreatment with a p38 MAPK specific inhibitor. The FF-induced VEGF upregulation was also significantly attenuated by a p38 MAPK inhibition. Taken together, FF extract induces VEGF production via p38 MAPK activation in human epidermal keratinocytes. These novel findings suggest that FF is useful as a potential agent with pro-angiogenic activity and may help to improve age-dependent reduction of the microvasculature in aged skin or to heal skin wound.

Early histological change in hard tissue from orthodontic force placed on microscrews in ovariectomized rats (난소 적출 백서에 식립된 마이크로스크류에 교정력 부여 시 나타난 초기 경조직 변화에 관한 연구)

  • Lee, Dea-Seung;Chang, Moon-Jung;Lee, Jin-Woo
    • The korean journal of orthodontics
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    • v.36 no.2 s.115
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    • pp.103-113
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    • 2006
  • Most elderly women experience a decrease in their bone density due to a deficiency of calcium intake, ovariectomy, or menopause. This study evaluated the usability of the microscrew as a skeletal anchorage system in these orthodontic treatment cases, using rats as a research group. The 4 month old sprague-dawley species rats were divided into two groups, the OS (Ovariectomy Screw), and the SS (Sham operation Screw) group. In both the OS and SS groups, microscrews were implanted into the palatal bone between the upper molar teeth and two upper incisors were retracted using NETE coil spring with 75 g of force. After 3days, the again after 7 days, 7 rats in each group were sacrificed. Three days before they were sacrificed, Alizarin red S was intraperitoneally injected, and their maxillary bone, tibia and blood from their hearts were taken. The components of the extracted blood were biochemically analyzed and non-decalcified grinding resin sections for maxillary bone and tibia were made. The sections were examined with a polarization microscope, and fluorescent microscope. Smaller concentrations of Ca and P, the inorganic substances closely related to bone density, were found in the extracted blood of the OS group. Both OS and SS groups showed a possibility of bone remodeling with a high concentration of ALP after 7 days. An increase in bone density on the tension and compression sides of the microscrew and the tension side of the tooth for both OS and SS groups was confirmed with a polarization microscope. However, the bone density of the pressure side of the tooth and apical side was decreased. More deposits of Alizarin red S in the bone after 7 days rather than 3 days seen with a fluorescent microscope suggested the existence of new bone formation.

Characteristics of Everbearing Strawberry Cultivars and the Effect of Precooling Treatment to Maintain Quality of 'Charlotte' Cultivar Grown on Highland in Summer Season (고랭지 사계성 딸기 품종 특성 비교 및 'Charlotte' 품종의 예냉 처리 효과)

  • Hwang, Dae Keun;Eum, Hyang Lan;Yeoung, Young Rog;Park, Kuen Woo;Hong, Sae Jin
    • Horticultural Science & Technology
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    • v.31 no.3
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    • pp.282-288
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    • 2013
  • This study was conducted to investigate the quality characteristics of eight everbearing strawberry cultivars and the effect of precooling treatment to maintain the quality during storage and shelf life of 'Charlotte'. Several quality parameters including firmness, soluble solids content (SSC), color, soluble sugars, and organic acids were evaluated. For Successful marketing everbearing strawberries required more than 1 N of firmness and $6^{\circ}Brix$ of SSC, respectively. 'Albion', 'Charlotte', and 'Goha' cultivars were higher in fruit SSC and 'Charlotte' cultivar was higher in fruit firmness among eight cultivars examined in this study. Fruit had more bright red color in 'Charlotte', 'Flamingo', 'GW-4', and 'San Andreas', which may reflect the consumer acceptance. Physicochemical characteristics of 'Charlotte' strawberry after with/without room precooling treatment were evaluated during storage at $4^{\circ}C$, $10^{\circ}C$, and $25^{\circ}C$ and additional 3 days at $25^{\circ}C$ for shelf-life. Weight loss increased about 8% in the fruits stored at $25^{\circ}C$ for 3 days, while in low temperature storage was about 2% for 7 days showing precooling was more effect on during shelf life periods rather than storage periods. Decay was not found during storage at $4^{\circ}C$ regardless of precooling treatment, but fungal growth was found in all the treatments after transferred to room temperature. Precooling treatment did not affect fruit color in shelf life period. For advanced marketing, everbearing strawberry should maintain in low temperature less than $4^{\circ}C$ to sustain quality, but the room precooling showed less significant effect to maintain quality on 'Charlotte' cultivar.

Reduction of the Antigenicity of Whey Protein by Enzymatic Hydrolysis (효소가수분해에 의한 유청단백질의 항원성 저하)

  • Ha, Woel-Kyu;Juhn, Suk-Lak;Kim, Jung-Wan;Lee, Soo-Won;Lee, Jae-Young;Shon, Dong-Hwa
    • Korean Journal of Food Science and Technology
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    • v.26 no.1
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    • pp.74-80
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    • 1994
  • As a preliminary study about the reduction of the antigenicity of whey protein isolate(WPI) by treatment of chymotrypsin, trypsin, pancreatin, and protease from Aspergillus oryzae, the properties and antigenicities of whey protein hydrolysates(WPH) were investigated. When degrees of hydrolysis (DH) were measured by use of trinitrobenzensulfonic acid(TNBS), the DH of the WPH treated by pancreatin or protease from Aspergillus oryzae$(5.05{\sim}11.47)$ were much higher than those of the tryptic or chymotryptic WPH$(15.67{\sim}20.20)$. And the pretreatments of heat$(75^{\circ}C)$, 20 min and/or pepsin resulted in higher DH of WPH, generally. When the molecular distributions of the WPH were determined by high performance size exclusion chromatography(HPSEC), the ratios of polypeptides with molecular weight more than 10kDa ranged from 12% to 36%, and the average molecular weights and the average peptide lengths of the WPH were $4,252{\sim}9,132$ dalton and $38{\sim}83$ amino acids, respectively. And there was no bitter taste in all of the WPH. Results of SDS-PAGE showed that most of intact native proteins were eliminated by the enzymatic hydrolysis but there were a few bands of peptides larger than 14.2 kDa in some WPH. When antigenicity was assayed by competitive inhibition enzyme-linked immunosorbent assay(cELISA), monovalent antigenicity of WPH to rabbit anti-WPI antiserum were lowered to $10^{-1.7}-10^{-4.9}$ times and less by the enzymatic hydrolysis. And the pretreatments of heat and pepsin resulted in the lowest antigenicicy within a group of enzymatic hydrolysis, especially in case of the pancreatic hydrolysate(PDP) whose antigenicity was found almost to be removed.

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Spatial Ability, Its Relationship to Mathematics Achievement, and Strategic Choices for Spatial Tasks Among Engineering Freshmen, and Gender Differences (공과대학 신입생들의 공간 시각화 능력의 수학 성취도와의 관계와 문제해결 전략 및 성별 차이에 관한 연구)

  • Kim, Yon Mi
    • Korean Journal of Cognitive Science
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    • v.28 no.3
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    • pp.149-171
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    • 2017
  • In this research, based on the fact that spatial ability is important for the achievement in the STEM fields, and technological innovation, Purdue Spatial Visualization Test-Rotation has been used to investigate engineering freshmen's spatial ability and gender differences. Students who have taken advanced mathematics courses in high school(those who have taken type B math test in Korean SAT test) and students with general math courses(those who have taken type A in Korean SAT-Math test) are included in this study to find out the relationship between mathematics achievement and spatial ability. Finding out the strategies taken by students was another aim of this study. This strategic differences between high achievers and lower achievers, male and female students were analyzed from students' self report. Spatial ability test score was highest in the SAT-Math type B male students, decreased in the order of type A male students, type B female students, and lastly type A female students. There was no substantial difference between second and third groups. In each group, male students' average score was 8~10% higher than female students, which affirms 2015's results. The correlation between spatial ability and mathematics achievement was negligible in each group, but male students' math score and spatial ability score were higher than that of female students. This can be interpreted that there is some correlation between these two. Strategic choices can vary in the continuous spectrum with analytic method and holistic method at both ends. From students' self report, using Mann-Witney test, it turned out that there exists strategic differences between male and female students. Male students have a tendency to use holistic strategy more often than female students. I also found that the strategy choice did not vary greatly among all score groups. For the perfect score groups, both female and male students used holistic strategy most frequently. For low achieving groups, there is an evidence that these students overuse one method compared to average or high achieving groups, which turned out to be less effective. Based on these, I suggest that low achieving students need to have more chances to adopt efficient strategies and to practice challenging problems to improve their spatial abilities.

Evaluation of $^{14}C$ Behavior Characteristic in Reactor Coolant from Korean PWR NPP's (국내 경수로형 원자로 냉각재 중의 $^{14}C$ 거동 특성 평가)

  • Kang, Duk-Won;Yang, Yang-Hee;Park, Kyong-Rok
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.7 no.1
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    • pp.1-7
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    • 2009
  • This study has been focused on determining the chemical composition of $^{14}C$ - in terms of both organic and inorganic $^{14}C$ contents - in reactor coolant from 3 different PWR's reactor type. The purpose was to evaluate the characteristic of $^{14}C$ that can serve as a basis for reliable estimation of the environmental release at domestic PWR sites. $^{14}C$ is the most important nuclide in the inventory, since it contributes one of the main dose contributors in future release scenarios. The reason for this is its high mobility in the environment, biological availability and long half-life(5730yr). More recent studies - where a more detailed investigation of organic $^{14}C$ species believed to be formed in the coolant under reducing conditions have been made - show that the organic compounds not only are limited to hydrocarbons and CO. Possible organic compounds formed including formaldehyde, formic acid and acetic acid, etc. Under oxidizing conditions shows the oxidized carbon forms, possibly mainly carbon dioxide and bicarbonate forms. Measurements of organic and inorganic $^{14}C$ in various water systems were also performed. The $^{14}C$ inventory in the reactor water was found to be 3.1 GBq/kg in PWR of which less than 10% was in inorganic form. Generally, the $^{14}C$ activity in the water was divided equally between the gas- and water- phase. Even though organic $^{14}C$ compound shows that dominant species during the reactor operation, But during the releasing of $^{14}C$ from the plant stack, chemical forms of $^{14}C$ shows the different composition due to the operation conditions such as temperature, pH, volume control tank venting and shut down chemistry.

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Studies on Salient Metabolites of Plant Tissues (I) -Nitrogen Metabolism and Proline Accumulation in Halophytes- (식물조직계(植物組織系)의 유효성분(有效成分)에 관(關)한 연구(硏究) [1] -내염성(耐鹽性) 식물(植物)의 Proline축적(蓄積) 및 질소대사(窒素代謝)-)

  • Cho, I.H.
    • Applied Biological Chemistry
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    • v.20 no.2
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    • pp.221-227
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    • 1977
  • Contents of proline and chloride in halophytes were $80-1700\;{\mu}g/gfw$ and 0.13-0.45 mM/gfw respectively. The content of proline was inversely proportional to that of chloride. Rhizomes of Phargmites communis Trin, a halophyte, were grown in non-saline medium and then taken to saline treatment for one or two weeks. Growth of P. communis was inhibited when salinized with 0.25M NaCl. Total nitrogen decreased and alcohol soluble nitrogen and proline increased when growth was retarded. The quantity of Fraction 1 protein decreased at 0.25M NaCl treatment. The accumulation of proline at high concentration in P. communis suggested that it might play a role in osmotic adjustment.

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A Research on Private apparel Brand's Product Strategy in Discounted Stores. (할인점의 의류PB 상품전략에 관한 연구)

  • Choi, Sung-Sik;Kim, Pan-Jin;Lee, Sang-Youn
    • The Journal of Industrial Distribution & Business
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    • v.2 no.2
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    • pp.25-38
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    • 2011
  • After the financial crisis, what has been the rapidly growth of large supermarkets, stores, and restaurants linked to concerns that have already reached saturation point, but the new opening large supermarkets is expected to continue into the future. The major supermarkets are continue to grow outward but growth slowed. And that is expected to continue differentiation of the product, acceptance the customer needs, acquiring high margin of sales products. Then the ongoing development of PB brand is to be positioned effective marketing strategy for overcoming the period of slow growth. In addition, big three local supermarkets continue to launch a clothing PB brand, expansion and operation strategy for the situation and based on this study and the success of the domestic large-Mart's PB and PB identifying problem and the need for differentiation and profit for the successful strategy is to discuss in this study. This research looks at the concept of major market's private brand, the strategy, the success example and the prospects, and views the globally rapid-growing private brands, not only having the limited role of distributing the products as retailers, but also having a control of the distribution channel as a manufacturing company. World's major advanced distribution companies, to differentiate their companies' products and increase the profitability, are putting a lot of efforts into private brand products, and there are many good examples that are globalizing, externally expanding, and creating high financial results. In this research, we presented three major domestic discount stores as examples to show that there is a need for a differentiated private brand management strategy in the saturated discount store industry in Korea. Also, we aim to provide a new product strategy for the future that has been saturated with discount stores to the limit, by providing suggestions that private brand products can be used as weapons with the strongest competiveness in the retail industry through pursuing store differentiations from thorough market analysis and product researches, meeting the customers' needs, and obtaining high margins. PB products, particularly clothing design, a thorough market analysis and product development trends and customer needs to reflect the acquisition of High margin differentiated powerful products and sustainable growth through the stores, large supermarkets, congested, a new breakthrough that can give a good opportunity to provide implications discount stores, new product strategy based on ways to limit proposed. This study discount the major three companies studied, the less strain is a generalization. In the future, domestic and local discount store brand PB, SPA brand that the multinational comparative analysis of the value of the PB expansion strategy centered on clothing, additional studies will be needed.

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