• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.537-543
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• 2019

Alumina(Al₂O₃) is a ceramic material used in industry with a range of particle sizes and characteristics. In this study, a boehmite sol was prepared by a hydrolysis and peptizing process using the Sol-Gel method from aluminum isopropoxide (AIP). γ-Al₂O₃ was prepared by drying and calcining. To prevent particle agglomeration during the manufacturing process, four kinds of polyvinyl alcohol (PVA) with molecular weights of 9,000~10,000, 31,000~50,000, 89,000~98,000, and 130,000 were added and three concentrations of HNO₃ (0.1, 0.3, 0.5 molar ratio) were added to determine their effects on the particles. The crystal structure, composition, particle size and shape of the prepared γ-Al₂O₃ were confirmed through x-ray diffraction (XRD), x-ray fluorescence analyzer (XRF), particle size analyzer (PSA), and field emission scanning electron microscopy (FE-SEM). As a result, γ-Al₂O₃ with a purity of approximately 98.2% was synthesized, and the particle size decreased and the uniformity increased with increasing ratio of HNO₃ addition and PVA molecular weight. From these results, the particle size can be controlled during the manufacturing process of γ-Al₂O₃ by controlling the addition ratio of PVA and HNO₃.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.70-77
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• 2020

Microalgae are independent organisms that perform photosynthesis and can alter the culture environment to increase accumulation of useful substances derived from microalgae. In this study, cell growth was measured by incubation for 39 days using MBBM, Neo medium, and seven light sources, which is the main factor affecting cell growth of microalgae S. obliquus. In the case of S. oliquus, which grew in MBBM and Neo medium, cell growth was highest under fluorescent light sources and Red2 LED (R660) light sources, and cell growth was lowest under Infra Red LED (R741) light sources. The average cell growth rate was 17.7% for MBBM and 15.4% for Neo. Comparing the effects of dry cell weight of Neo medium containing nutrients on the production of aquatic plants, MBBM and dry cell weight of Neo resulted in higher cell growth than Neo medium under all LED light sources except for Blue LED (B450). This proves that MBBM is more suitable for increasing the cell growth of microalgae than Neo medium and confirms that light source selection is important in the production of useful materials through mass cultivation of microalgae in the future.

• Journal of the Korean Institute of Landscape Architecture
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• v.48 no.5
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• pp.67-79
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• 2020

Plans to mitigate overheating in urban areas requires the identification of the characteristics of the thermal environment of the city. The key information is the distribution of higher and lower temperatures (referred to as "hotspot" or "coldspot", respectively) in the city. This study aims to identify the areas within Jeonju City that are suffering from increasing land surface temperatures (LST) and the factors linked to such this phenomenon. To identify the hot and cold spots, Local Moran's I and Getis-Ord Gi^* were calculated for the LST based on 2017 images taken using the thermal band of the Landsat 8 satellite. Hotspot analysis revealed that hotspot regions, (the areas with a high concentration of Land Surface Temperature) are located in the old town area and in industrial districts. To figure out the factors linked to the hotspots, a correlation analysis, and a regression analysis taking into account environmental covariates including Normalized Difference Vegetation Index (NDVI) and land cover. The values of NDVI showed that it had the strongest effect on the lowering LSTs. The results of this study are expected to provide directions for urban thermal environment designing and policy development to mitigate the urban heat island effect in the future.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.31 no.4
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• pp.447-453
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• 1986

Germination and seedling elongation of soybeans [cult. ‘Williams’] were measured at two temperatures (15 and 3$0^{\circ}C$), three seed water contents (30, 50, and 70%), and with and without polyethylene glycol-8000 (PEG) treatments. A split-plot design was used with four replications. Observations were made from two hours to eight days for each treatment combination. Seeds were soaked with 30% PEG solution with 0.2% thiram at 15 C for six days, rinsed with deionized water and dried at 25.5$^{\circ}C$ for three days. Ten treated or untreated seeds were placed on Whatman No. I (9 cm) filter paper in plastic petridishes to which sufficient deionized water was added to adjust seed moisture content to the desired level. The dishes were then sealed with parafilm and placed in a continuous programmed temperature chamber under dark condition. Seedling growth did not occur at either temperature when moisture content was 50 percent or less. Osmo-conditioning with PEG showed positive effects on seedling moisture uptake and seedling growth at 15$^{\circ}C$ but little effect at 3$0^{\circ}C$. Seedling moisture content increased rapidly early in the germination period and reached 60% at 15 C for 56 hours and at 3$0^{\circ}C$ for 28 hours. Seedling growth started when seed moisture reached a critical point of 60% at 15$^{\circ}C$, however, growth started after 20 hours of germination at 3$0^{\circ}C$. Seedlings of soybeans elongated more than four times faster at 3$0^{\circ}C$ than at 15$^{\circ}C$. Water uptake during germination was characterized by two phases in this experiment.

• Korean Journal of Environmental Biology
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• v.37 no.3
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• pp.229-248
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• 2019

This study was carried out to investigate the flora of Mt. Jaamsan on the Gyeongsang supergroup, Korea. From the results of eight field surveys from March to October 2017, we have identified 530 total taxa, representing 483 species, eight subspecies, 35 varieties, two forms, and two hybrids, which were placed in 325 genera and 110 families. The plant formation of Mt. Jaamsan is the deciduous broad-leaved and conifer mixed forests, which are the common ones in the middle part of the Korean Peninsula. Most of the mountain is covered with young secondary forest, which is mainly composed of Quercus spp., and Pinus. Out of these 530 taxa, 12 are endemic to Korea, 17 taxa are listed on the Korean Red List of threatened species, 65 are floristic target species, and 55 are invasive alien species. The percentage of naturalized index(NI) and urbanization index (UI) were 10.4% and 17.2%, respectively. Mt. Jaamsan has a high plant diversity, including endemic and rare species, which consist of geomorphological landscapes. We considered that the composition and distribution of species are affected by the different environmental factors according to the sedimentary rocks, drying ridges, valleys, and streams. Together with the rocks and soils were the substrate type that play a major role in providing the unique habitats for sun plants in the area.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.625-637
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• 2020

In order to decide the naval ship weapon system acquisition for national policy/market economy activities, the decision makers can determine policy based on current technology level/concentration/utilization. For this, the decision makers apply the major common technology field analysis using patents data. As a method for collecting patent data, we can collect patent data of domestic mobile carriers through the Korea Intellectual Property Rights Information System of Korean Intellectual Property Office. As a result, we collected 14,964 patents/352 International Patent Classification(IPC) types. Based on these data, we performed three analysis processes (SNA, PCA, ARIMA, Text Mining) and got each result from extracting 58 IPC types of SNA and 7 IPC types of PCA. Based on the analysis results, we have confirmed that 7 IPC(B63B, H01M, F03D, B01D, H02K, B23K, H01H) types are the Major Common Technology Distribution of domestic Defense Companies.

• Journal of Korean Medical classics
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• v.18 no.4 s.31
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• pp.101-119
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• 2005

금원사대가적태두류완소(金元四大家的泰斗劉完素), 1110년생어하북성하간현(年生於河北省河間縣), 졸어(卒於)1200년(年), 향년(享年)90세(歲). 타통과연구(他通過硏究)${\ulcorner}$황제내경(黃帝內經)${\lrcorner}$화(和)${\ulcorner}$상한론(傷寒論)${\lrcorner}$, 저술료(著述了)${\ulcorner}$소문현기원병식(素問玄機原病式)${\lrcorner}$, ${\ulcorner}$황제소문선명론방(黃帝素問宣明論方)${\lrcorner}$, ${\ulcorner}$소문병기기의보명집(素問病機氣宜保命集)${\lrcorner}$, ${\ulcorner}$상한표본심법류췌(傷寒標本心法類萃)${\lrcorner}$, ${\ulcorner}$상한직격론(傷寒直格論)${\lrcorner}$등저작(等著作). 령외, 응용운기대이론진행연구(應用運氣對理論進行硏究), 주장(主張)‘화열론(火熱論)’, 제출이한량약물치료질병적방법, 사금원시대재의학상(使金元時代在醫學上), 형성료백가쟁명적국면(形成了百家爭鳴的局面). 필자통과대류완소적방제학설급임상경험적연구(筆者通過對劉完素的方劑學說及臨床經驗的硏究), 득출여하결론(得出如下結論): 재방제학설상(在方劑學說上), ${\ulcorner}$황제소문선명론방(黃帝素問宣明論方)${\lrcorner}$중(中), 기사용적(其使用的)${\ulcorner}$상한론(傷寒論)${\lrcorner}$화각가급기제자문운용방제(和各家及其弟子們運用方劑), 공포괄(共包括)366개(個). 대부분주장료이용신고적한약(大部分主張了利用辛苦的寒藥), 래개통울결(來開通鬱結), 조습제열(操濕除熱). ‘상복보양(常服保養)’시인위여기소거주적중국북방(是因爲與其所居住的中國北方), 기후건조(氣候乾操), 인문다식습성강(人們多食濕性强), 차교표한적식물(且較標悍的食物), 소이유사인체장위비조적경향(所以有使人體腸胃秘操的傾向). ${\ulcorner}$황제소문선명론방(黃帝素問宣明論方)${\lrcorner}$적(的)366개방중(個方中), 유산제(有散劑)126개(個), 탕제(湯劑)87개(個), 기중(其中), 지유(只有)18개방가칭지위진정적탕제, 기여도접근위자산(其餘都接近爲煮散). ${\ulcorner}$황제소문선명론방(黃帝素問宣明論方)${\lrcorner}$중소나열적주요방제유(中所羅列的主要方劑有)‘방풍통성산(防風通聖散)’, ‘삼화신우환(三花神佑丸)’, ‘쌍해산(雙解散)’, ‘삼일승기탕(三一承氣湯)’, ‘대금화환(大金花丸)’, ‘익원산(益元散)’, ‘대건중탕(大建中湯)’, ‘당귀룡담환(當歸龍膽丸)’, ‘비방다주조산(秘方茶酒調散)’, ‘계령감로산(桂零甘露散)’, ‘천궁석고탕(川弓石膏湯)’, ‘전성산(全聖散)’, ‘지유탕(地楡湯)’, ‘인참산(人參散)’, ‘작약탕(芍藥湯)’, ‘내통황연탕(內統黃連湯)’, ‘신궁환(神芎丸)’, ‘도환산(倒換散)’등(等). 재임상경험상(在臨床經驗上), 류씨유풍부치료경험(劉氏有豊富治療經驗), 단시유감적시몰유전하일부관우의안방면적저작(但是遺憾的是沒有傳下一部關于醫案方面的著作). 재질병적치료상(在疾病的治療上), 가간출기유독창적견해(可看出其有獨創的見解), 저일점도견우(這一點都見于)${\ulcorner}$소문현기원병식(素問玄機原病式)${\lrcorner}$등이론저작(等理論著作), 우기산견어(尤其散見於)${\ulcorner}$황제소문선명론방(黃帝素問宣明論方)${\lrcorner}$중(中).

• Journal of Korean Ophthalmic Optics Society
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• v.17 no.2
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• pp.233-239
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• 2012

Purpose: In the study, the change of protein and lipid deposits on soft contact lens by drinking was investigated. Methods: Fifty male subjects wearing soft contact lens were surveyed whether they felt any discomfort induced by drinking or not. Further, 32 male subjects who has no ocular disease drank 190 mL alcohol. The protein and lipid deposits on soft contact lens (etafilcon A material) of subjects were measured after 4 hours later and compared with those of non-drinking subject. Results: When subjects drink alcohol with soft contact lens on, 58% of subjects answered they experienced the change of lens awareness such as stiffness, blurry sight, dryness and so on. The protein deposit on soft contact lens increased an average of $59.3{\mu}g/lens$ by drinking and the case of more than double in protein deposit was reached in 9 eyes. However, the protein deposited on soft contact lens was lysozyme which was unchanged by drinking. The amounts of cholesterol and methyl oleate after drinking were 85.5% (p=0.25) and 52.6% (p=0.002) of non-drinking's indicating some change of lipid deposit on soft contact lens by drinking. Conclusions: The results showed the composition of protein and lipid deposited on soft contact lens was changed due to drinking. Thus, it is suggested that wearing soft contact lens when drinking might be one of the reasons to feel discomfort.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.355-362
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• 1983

A vacuum-packed seasoned-dried product of sea mussel, Mytilus edulis, caught in the southern coasts of Korea, was prepared and stored at $35^{\circ}C$ for 70 days to test quality stability. Sea mussel, purchased from Jagalchi fish market in Busan, was steamed, shucked and eliminated byssus. The sea mussel meat was seasoned with the seasoning solution prepared with sugar, salt, sorbitol, glycerol, monosodium glutamate, 5'-ribonucleotide and smoke flavor (Smoke-EZ, Alpha Foods Co., Ltd.). After seasoning, the meat was dried at $52-58^{\circ}C$ for three hours, vacuum-packed in the laminated plastic film bag($14{\times}15cm$), and finally sterilized at $120^{\circ}C$ for 26 minutes in hot water circulating retort. The moisture, water activity, color value(L, a and b value), texture, TBA value and viable bacterial count of the products were determined during the period of storage at $35^{\circ}C$. From the results obtained, it became clear that the product could be preserved in a good quality for 70 days at $35^{\circ}C$, though a slight decrease in moisture content and development of a pale brown color was resulted. Judging from the sensory evaluation on flavor, the products containing smoke flavor were most desirable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.146-152
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• 2018

In this study, to improve the performance of asphalt mixtures for plastic deformation occurring mainly in Korea, complex modifiers were prepared by mixing powders and liquid type modifiers. The main constituents were powdery diatomaceous earth, mica and carbon black, and liquid type solid 70% SBR latex. The tensile strength ratios for the two asphalt mixtures used in the test were above 0.80 for the Ministry of Land Transportation (2017) asphalt mixture production and construction guidelines. The effects of increasing the tensile strength in the dry state was more than 14% when the composite modifier was added. The deformation rate per minute by the wheel tracking test load was an average of 0.07 to 0.147 for each mixture. The strain rate per minute was improved by the modifier, and the dynamic stability was improved by almost 100% from 295 to 590. In addition, the final settling was reduced from 11.38 mm to 9.57 mm. A plastic deformation test using the triaxial compression test showed that the amount of deformation entering the plastic deformation failure zone at the end of the second stage section and in the third stage plastic deformation section was 1.76 mm for the conventional mixture and 1.50 mm for the complex modifier mixture. The average slope of the complex modifier asphalt mixture mixed with the multi-functional modifier was 0.005 mm/sec. The plastic deformation rate is relatively small in the section where the road pavement exhibits stable common performance, i.e. the traffic load.