• Title/Summary/Keyword: content of research

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Study on the Phosphorus Content of Algae (藻類細胞內 燐含量에 관한 연구)

  • Song, Jun-Sang;Lee, Mun-Ho;Yang, Sang-Yong
    • Journal of Environmental Health Sciences
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    • v.14 no.1
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    • pp.55-61
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    • 1988
  • Study was conducted on how the phosphorus content of algae changed by the algal species and the algal growth conditions. Phosphorus contents were not so different by algal species if algae grow on the same phosphorus concentration. Phosphorus content of algae grown on higher P medium was higher than that of algae grown on lower P medium. Algae excrete P-compounds from cell to the medium when the dissolved reactive phosphorus is depleted in the medium, and the excreted P-compounds were decomposed by algae and used for the growth of algae. Phosphorus content of algae grown in the P-limited condition was about 5-1 $\mu$gP/mg dry wt., but that of algae grown in the condition not P-lirnited was above 10$\mu$gP/rng dry wt.

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Preparation of Nanocapsules Containing Phase Change Materials by Miniemulsion Polymerization

  • Oh, Keun Jin;Kim, Dae-Su;Lee, Jae Heung;Choi, Kil-Yeong;Lee, Changjin
    • Journal of Adhesion and Interface
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    • v.4 no.1
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    • pp.35-42
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    • 2003
  • Polystyrene nanocapsules containing octadecane as a core material were prepared by miniemulsion polymerization. The morphology and size of the nanocapsules were measured with varying the surfactant concentration, content of initiator, core/shell ratio and content of comonomer. The morphologies of the prepared nanoparticles were examined by a scanning electron microscope, a transmission electron microscope and the core material was confirmed by a differential scanning calorimeter. The particles below 70 nm in diameter were formed at a high surfactant concentration. The size of the nanoparticles was not significantly affected by the initiator content. With increasing the core/shell ratio and polar comonomer content, the particle size and its distribution were increased.

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Changes of Physicochemical Quality in Hardy Kiwifruit (Actinidia arguta) during Storage at Different Temperature

  • Park, Youngki;Kim, Chul-Woo
    • Korean Journal of Plant Resources
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    • v.28 no.3
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    • pp.329-332
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    • 2015
  • The effect of storage temperature and the storage period of hardy kiwifruits on the fruit firmness, soluble solids and fruit weight were studied in this work. The investigation was carried out on the Sae-Han cultivar of Actinidia arguta. It has an edible smooth skin and contains high amounts of sugar and vitamin C (ascorbic acid). In this research, the measurement of fruit firmness, soluble solids, and fruit weight were carried out at various temperatures (5, 10, 15, and 20℃) during 14 days. Fruit firmness rapidly decreased and soluble solids content increased at 15 and 20℃. We also investigated the correlation between fruit firmness and soluble solids content. There was a strong correlation between fruit firmness and soluble solids content. That means that fruit firmness affect the soluble solids content of hardy kiwifruit.

Lignans from the Fruits of Schizandra chinensis and Their Inhibitory Effects on Dopamine Content in PC12 Cells

  • Seo, Seon-Mi;Lee, Hak-Ju;Park, Young-Ki;Lee, Myung-Koo;Park, Jae-In;Paik, Ki-Hyon
    • Natural Product Sciences
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    • v.10 no.3
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    • pp.104-108
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    • 2004
  • Five lignans including gomisin N (1), wuweizisu C (2), gomisin L1 (3), (+)-deoxyschizandrin (4), and gomisin J (5) have been isolated from the fruits of Schizandra chinensis. The structures of the isolated compounds were elucidated by analyzing MS and NMR spectra. Effects of the compounds isolated in this study on the dopamine content in PC12 cells were investigated to evaluate their inhibitory effectiveness. The gomisin N, wuweizisu C, and gomisin J showed 25.4%, 39.8%, and 35.1 %, respectively, inhibition effect on dopamine content in PC12 cells at the concentration of $50\;{\mu}g/ml$.

Changes in physicochemical characteristics of cation exchange resins by high dose gamma irradiation

  • Seung Joo Lim;Wang Kyu Choi;Mansoo Choi
    • Nuclear Engineering and Technology
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    • v.56 no.5
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    • pp.1777-1780
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    • 2024
  • Chemical and thermal characteristics of cation exchange resins were examined after irradiation of gamma rays. The degradation of cation exchange resins was mainly observed at doses of up to 500 kGy, whereas the balance between degradation and cross-linking reactions was sustained at 700 kGy. While the carbon content decreased significantly up to a maximum dose of 500 kGy, it showed an increase at higher doses. Conversely, the oxygen content exhibited a decrease in contrast to the carbon content. The continuous reduction in sulfur content was attributed to the decomposition of sulfonic groups. Gamma-ray irradiation caused a decrease in the initiation temperature of sulfonic groups and PS-DVB, but unlike the chemical properties of cation exchange resins due to gamma-ray irradiation, the thermal properties of resins remained unaffected.

Mixed Display Platform to Expand Comfortable Zone of Stereoscopic 3D Viewing

  • Yang, Ungyeon;Kim, Namkyu;Seo, Jinseok;Kim, Ki-Hong;Lee, Gil-Haeng
    • ETRI Journal
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    • v.35 no.2
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    • pp.352-355
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    • 2013
  • Common stereoscopic three-dimensional (3D) display has a convergence and accommodation conflict that violates the natural human cognitive process of viewing. This weakness exposes the challenge in supporting fun factors while eliminating safety problems in the 3D viewing experience. Thus, human factors have become a major research topic. In this letter, we propose a 3D stereoscopic visualization platform that can expand the sense of a 3D space by fusing organically mixed stereoscopic displays to provide a continuous feeling of 3D depth. In addition, we present pilot test results to show the possibility of the technical implementation of the proposed platform and note ongoing research issues to be addressed.

Quality Characteristics and Antioxidant Activity of Regional Traditional Soybean Pastes (Deonjang) in Jeonbuk Province (전북지역 전통 된장의 품질특성 및 항산화 활성)

  • Song, Young Eun;Han, Hyun Ah;Lee, Song Yee;Shin, So Hee;Choi, So Ra;Kim, So Young
    • The Korean Journal of Food And Nutrition
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    • v.32 no.6
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    • pp.598-610
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    • 2019
  • The purpose of this study was to investigate the quality characteristics and antioxidant activity by collecting four times on six samples of Jeonbuk regional soybean pastes (Doenjang) traditionally prepared for this study. The water content of samples decreased according to progress of the aging period and the water content of the fourth sample collected was 42.40~59.64% (p<0.05). The salinity of the fourth Doenjang samples was 11.80~18.60%. The amino-type nitrogen content was 122.67~540.33 mg% immediately after the preparation of Doenjang in the Jeonbuk region and the content of the fourth collection samples increased from 251.49 to 982.36 mg% (p<0.05). The isoflavone glycosides decreased but daidzein, genistein and glycitein, which are aglycones, increased during aging periods. The total polyphenol content of the fourth collected samples was 11.99~19.27 mg GAE/g (p<0.05). The DPPH radical scavenging activity, ABTS radical scavenging activity and FARP of the fourth Doenjang samples were 51.88~81.21%, 84.14~90.32%, and 1.08~3.11 mg Trolox/g, respectively. As a result of quality analysis on Doenjang, the superiority of traditional Doenjang has been proven by the increase of amino nitrogen content and antioxidant activity according to the aging period. However, factor analysis on quality differences of regional Doenjang should be conducted to ensure standardization and quality improvement.

Mitigating the ICA Attack against Rotation-Based Transformation for Privacy Preserving Clustering

  • Mohaisen, Abedelaziz;Hong, Do-Won
    • ETRI Journal
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    • v.30 no.6
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    • pp.868-870
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    • 2008
  • The rotation-based transformation (RBT) for privacy preserving data mining is vulnerable to the independent component analysis (ICA) attack. This paper introduces a modified multiple-rotation-based transformation technique for special mining applications, mitigating the ICA attack while maintaining the advantages of the RBT.

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Hydraulic Conductivity of Bentonite-Sand Mixture for a Potential Backfill Material for a High-level Radioactive Waste Repository

  • Cho, Won-Jin;Lee, Jae-Owan;Kang, Chul-Hyung
    • Nuclear Engineering and Technology
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    • v.32 no.5
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    • pp.495-503
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    • 2000
  • The hydraulic conductivities in the bentonite-sand mixtures with high density were measured, and the effects of sand content and dry density on the hydraulic conductivity were investigated. The hydraulic conductivities of the bentonite-sand mixtures with a dry density of 1.6 Mg/㎥ and 1.8 Mg/㎥ are less than 10$^{-11}$ m/s when the sand content is not higher than 70 wt%. However at the sand content of 90 wt%, the hydraulic conductivity increases rapidly At the same dry density, the logarithm of hydraulic conductivity increases linearly with increasing sand content. The hydraulic conductivity of the bentonite-sand mixture can be explained by the concept of effective clay dry density, and using this concept, the hydraulic conductivities for the mixtures with various sand contents and dry densities can be estimated.

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An Analysis on the Content Elements of Housing Area in Middle School Technology·Home Economics Textbooks by 2009 Revised Curriculum (2009 개정 중학교 기술·가정 교과서 주생활영역의 내용요소 분석)

  • Cho, Han Gyul;Jang, Sang Ock
    • Korean Journal of Human Ecology
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    • v.24 no.2
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    • pp.297-325
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    • 2015
  • The purpose of this research is to analyze content elements of Housing area in 2013 middle school Technology Home Economics textbooks 1 and 2, total of 22 according to 2009 revised curriculum. The analysis method was content analysis, focusing on contents of main text, tables & figures, reading material, and activity materials by their content elements. This research will contribute in obtaining suggestion for the post curriculum/textbook development and helping teachers to perform a lesson. The results are as follows. First, Housing area included 1 to 4 content elements per each units, from 2 chapters and 6 units. The content elements stated in Home economics curriculum were total of 16 which consists of 'the meaning of housing,' 'housing types,' 'family forms,' 'family life style cycle,' 'life style,' 'neighboring environment,' 'co-living values,' 'air environment,' 'heat environment,' 'light environment,' 'acoustic environment,' 'space division,' 'circulation', 'effective use of space,' and 'sustainable dwelling practice.' All of these components are dealt with in every textbooks. Second, the numbers of content elements provided in each textbooks were the same, however they showed difference in their contextual aspect. Some contents need supplemental material for their lacking content element. Others need proper understanding of the concept because some showed different contents from the appropriate content elements. Third, repetitions in content elements were observed, the contents of 'co-living values' in textbook 1 and 'sustainable dwelling practice' in textbook 2 were similar in terms of eco-friendly housing, co-housing and universal housing. These two content elements should be merged as one next curriculum, or should be stated together in one subunit.