• Proceedings of the Korea Concrete Institute Conference
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• 1993.10a
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• pp.108-112
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• 1993

The term Alkali-Silica Reaction (ASR) is used to describe a reaction between certain siliceous aggregates and hydroxyl ions present in the pore fluid of a concrete. The ASR is affected by the content of alkali, the particle size and the content of reactive aggregate, water-cement ratio, humidity, temperature and so on. In this paper, the fluence of alkali content and kind of added alkali to the ASR was studied. As a result, the more the content of alkali was increased, the more the mortar-bar was expand and the expansion of mortar-bar was showed differently with the added alkali kinds, The reaction products by ASR were observed by SEM(Scanning Electron Microscope) and analyzed by EDXA(Energy Dispersive X-ray Analysis) also and showed a gel composed of alkali(Na+, K+), silica and calcium.

• Journal of the Korean Home Economics Association
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• v.18 no.1
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• pp.35-40
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• 1980

This study was designed to find out the mineral content in Korean foods. The data will be used as a fundamental guide in planning sodium and potassium restricted diet in Korea. The study is part 6 sodium and potassium content in meat, eggs and fish. The previous study is s follows: part1 and part 5 on vegetables and fruit, part 2 on cereals, part 3, on milk and soft drinks and part 4 on orange juice and nectars. part 6 includes 10 beef cuts, 5 retail items of pork, 4 parts of chicken, 2 kinds of eggs and 15 individual kinds of fish were collected from the market and analyzed for the content of sodium and potassium by atomic absorption spectrophotometry. The following tables 1-5 show the result.

• Journal of Plant Biology
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• v.18 no.4
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• pp.143-149
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• 1975

For the evaluation of drought resistance of the plant, the growth of Lespedeza bicolor Turcz. var. japonica Nakai was analyzed by the control of water content of soil: 1. The growth of leaf, stem and root showed high value in accordance with the increase of soil water content. 2. The formation of nodule was alos increased as the content of soil water became higher. 3. The highest water content of the plant was shown in the plots of 30 and 40% of water centent in soils and in the middle of the growing period (August-September). 4. The C/F ratio in the early period of the growth(July) was similar in each plot, but showed a higher value as the water centent of soil became higher at the later period(October). 5. The T/R ration increased in early period of the growth as the soil water content became higher, but it was decreased to the value of 1 in each plot.

• Journal of Plant Biology
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• v.22 no.1_2
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• pp.1-4
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• 1979

Wild soybean plants(Glycine ussuriensis) collected from Korea(47 strains) and abroad(41 strains) were grown under field condition and classified according to the growth habit. Seeds were analyzed for protein content. The results were as follows: 1. Wild soybean plants were classified into three groups each by seed size, growth habit of stem, leaf size and flowering time. 2. Seed protein was higher in the strains with large leaves, tendril, stem or late flowering. 3. Glycine gracilis, supposed to be the intermediate species between cultivated and wild soybean(according to the stem growth habit, straight or semitendril, and seed size) was medium in protein content of seeds. 4. The average protein content of Glycine ussuriensis, 43.2%, was highest in comparison with those of others such as G. gracilis, 37.5%, or G. max, 36.2%. 5. One hundred seed weight of Amphicarpaea trisperm, similar to the wild soybean, was almost same as Glycine ussuriensis, but protein content of this species was lower than wild soybeans.

• Magazine of the Korean Society of Agricultural Engineers
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• v.18 no.4
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• pp.4251-4258
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• 1976

In the construction of earth dam, embankment and highway by filling, a compaction contributes to increasing the density of soil by applying pressure. The effect of compaction depends on various factors such as soil type, moisture content, gradation, consistency, and compaction energy. In this study, the correlations amone maximum dry density, moisture content, dry density, and moisture content are analyzed. Some results obtained in this study are summarizep as follows. 1. The maximum dry density sinoreases with increased of optimum moisture content and the correlations of them can be represented by; ${\gamma}$dmx=a-b(W0) 2. Maximum dry density and liquid limit show negative linear correlation and can be represented by; ${\gamma}$dmx=a-b(LL). 3. Optimum moisture content and liquid limit, plastic limit show positive linear correlation and can be represented by the following equation, W0=a+b(LL) W0=a+b(PL). 4. Liquid limit and plastic limit show positive linear correlation, and can be represented by the following equation, LL=a+b(PL).

• Child Health Nursing Research
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• v.10 no.4
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• pp.431-441
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• 2004

Purpose: The purpose of this study was to develop a sexuality education course of study for students in the lower grades of elementary school. Method: On the basis of the sexuality education guidebook for elementary school students published by Korea Ministry of Education & Human Resources Development, the state-designated textbooks for first to third grade were analyzed. Results: 1) In the category of physical and psychological development, physical development and psychosexual development content were covered, but not sexual health content. 2) In the category of understanding of human relationship, marriage and family, and the opposite sex and love were presented but self-determination and selection were only partially presented. 3) In the category of sexual culture and sexual ethics, sexual role in society was covered, but not social environment or equality of the sexes. Conclusion: These results suggest that content on sexuality which is not covered in textbooks for students in lower grades should be included in other school courses or activities in class.

• Journal of Ginseng Research
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• v.19 no.3
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• pp.254-259
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• 1995

The content and composition of saponin compounds of Panax species were analyzed according to their species, region and processing type of red and white ginseng. The species employed were Korean-, Chinese-, Japanese red ginsengs, and Korean white ginseng of Panax ginseng, American- and Canadian ginsengs of Panax quinquefolium, and Panax notoinseng. Twelve main saponin components in the ginseng were identified and quantified using TLC and HPLC. All three species had remarkably different content and composition. However, within each species they were similar. Twelve major ginsenosides were determined in P. ginseng, eight in p. quinquefolium, and six in P. notoginseng. Of the components of P ginseng Rf, $Rh_1$, $Rh_2$ and Ra were not detected in P quinquefolium, and $Rb_2$, Rc, Rf, $Rh_2$, Ra and Ro not detected in P. notoinseam. Crude saponin content and protopanaxadiol/protopanaxatriol saponin ratio were compared. They were 4.81~5.24% and 1.27~ 1.45 in p. ginsengs, 7.01~7.25% and 2.12~ 2.15 in p. quinquefolium, 9.80% and 0.99 in P. notoineng. The prosapogenin and sapogenin content were different among the Panax species.

• Corrosion Science and Technology
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• v.5 no.3
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• pp.94-98
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• 2006

The next generation nuclear power reactor will use Pb-Bi as the cooling material. The steel structure materials such as HT-9 used in the reactor suffer from corrosion when they are exposed to high temperature Pb-Bi. Therefore corrosion should be prevented to use Pb-Bi as the coolant material without any safety problem. One method is to control the oxygen content in Pb-Bi. An appropriate amount of oxygen in Pb-Bi can produce a thin oxide layer on steel, and this layer protects the steel from corrosion attack. Since the required oxygen content in Pb-Bi is in the range of $10^{-5}$ to $10^{-7}$ wt%, this small oxygen content can be controlled by flowing a mixture of hydrogen gas and water vapor. The stagnant corrosion test of HT-9 samples was performed by controlling the oxygen content up to 2,000 hours. The corrosion behavior of HT-9 was analyzed at the temperatures of $500^{\circ}C$ and $650^{\circ}C$ with a reduced condition and a oxygen content of $10^{-6}$ wt%.

• Food Science and Preservation
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• v.5 no.2
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• pp.119-122
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• 1998

This study was conducted to blow the effect of postharvest physiological changes on garlic quality according to its ecotypes and storage temperatures. The changes of water, total soluble solids, crude stein, md total fructans were measured and the rates of respiration and sprouting were analyzed during storage at 20$^{\circ}C$ and 30$^{\circ}C$. The decrease of water content and the increase of total soluble solids were reversely appeared during garlic storage. The crude protein content was gradually increased during storage but total fructan content was decrased. The respiration late was maximized at 60days after storage and the spouting rate was gradually increased. In the aspect of ecotypic characteristics, the water content, fructan content and sprouting rate were higher in 'Namdo' cultivar than those of southern type. The high storage temperature (30$^{\circ}C$) controlled spouting and loss of fructan, and it was effective to maintain the garlic quality.

• Journal of Smart Tourism
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• v.1 no.3
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• pp.21-29
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• 2021

This study explored the relationship between post types and linguistic characteristics in marketer-generated content and social media engagement to find the optimized content to enhance social media engagement level. Post data of 23,588 marketer-generated content were collected from 50 states' destination marketing organization Facebook pages in the United States. The collected data were analyzed by employing social media analytics, linguistic analysis, multivariate analysis of variance, and discriminant analysis. The results showed that there are significant differences in both engagement indicators and linguistic scores among the three post types. Based on research findings, this research not only provided researchers with theoretical implications but also suggested practitioners the most effective content designs for travel destination marketing in Facebook.