• Korean Journal of Environmental Agriculture
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• v.41 no.3
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• pp.191-198
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• 2022

BACKGROUND: Plants can be grown using a culture medium without soil using a hydroponic system. Crop production by the hydroponic system is likely to increase as a means of solving various problems in the agricultural sector such as aging of rural population and climate change. Different water sources can be used to prepare the culture medium used in the hydroponic system. Therefore, it is necessary to study the effect of different water sources on crop production by the hydroponic system in order to explore the applicability of various water resources. METHODS AND RESULTS: Lettuce was cultivated by the hydroponic system and three different water sources [tap water (TW), bottled water (BW), and groundwater (GW)] were used to compare the effect of water sources on lettuce growth. The three kinds of waters with a nutrient solution (TW-M, BW-M, GW-M) were also used as the media. After the six-week growth period, the lettuce length and weight, the number of leaves, and the contents of chlorophylls and polyphenols were compared among the different media used. The lettuces did not grow in the waters without the nutrient solution. In the media, the lettuce growth and the contents of chlorophylls were affected by the different water sources used to prepare the media, while the contents of polyphenols were not affected. The absorbed amounts of ions by lettuces, especially Ca and Zn ions, and the dry weight of the harvested lettuces showed a strong positive correlation. CONCLUSION(S): Overall, this study shows that different water sources used for growing lettuce in a hydroponic system can affect lettuce growth. Further studies on the enhancement of crop qualities using different water sources may be required in future studies.

• Korean Journal of Environmental Agriculture
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• v.41 no.4
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• pp.310-317
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• 2022

BACKGROUND: The salt in soil interrupts crop growth. Therefore, water resources are used to remove any salt found in the soil. However, water resources have been reduced by global warming; thus, a new study is required into reducing the salt in soil. Recently, the bottom ash (BA) of a biomass power plant was found to be similar to biochar. Hence, it can be used to remove heavy metals and wastewater through the adsorption characteristics of BA. The objective of this study was to evaluate the improvement effects on crop growth in saline soil containing the BA from biomass power plants. METHODS AND RESULTS: The effect on crop growth in the saline soil supplemented with BA was studied with the crop-planted pots, which were packed by reclaimed greenhouse soils collected from Byolyang, Suncheon. The BA application level was 25, 50, 100, 200, and 400 kg/10a (referred as BA25, BA50, BA100, BA200, and BA400, respectively). The BA increased the fresh weights of the leaf and root, while nitrogen uptake increased by approximately 24-102% and 54-77%, respectively for the lead and root. The phosphorous uptake increased by 38%, although only in the leaf of the lettuce. In the case of soil, BA increased water content, pH, EC, CEC, and NH₄⁺ and the SAR of the soil decreased by 5-15%. The bottom ash increased the contents of Ca²⁺ and Mg²⁺, and fixed the amount of Na⁺. CONCLUSION(S): It was confirmed the bottom ash of a biomass power plant, based on wood pellets, improved crop growth, and increased the nutrient uptake of crops in saline soil. In addition, bottom ash, which has a wide range of porosity and high values of pH and EC, improved properties of the saline soil. However, the BA has a large amount of B, As, and heavy metals. Finally, it may require a study on the safety and contamination of heavy metals contained in the bottom ash, which would be applied in soil for a long time.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.167-174
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• 2019

A process-oriented crop growth model can simulate the biophysical process of rice under diverse environmental and management conditions, which would make it more versatile than an empirical crop model. In the present study, we examined chronology and background of the development of the rice growth models in Korea, which would provide insights on the needs for improvement of the models. The rice crop growth models were introduced in Korea in the late 80s. Until 2000s, these crop models have been used to simulate the yield in a specific area in Korea. Since then, improvement of crop growth models has been made to take into account biological characteristics of rice growth and development in more detail. Still, the use of the crop growth models has been limited to the assessment of climate change impact on crop production. Efforts have been made to apply the crop growth model, e.g., the CERES-Rice model, to develop decision support system for crop management at a farm level. However, the decision support system based on a crop growth model was attractive to a small number of stakeholders most likely due to scarcity of on-site weather data and reliable parameter sets for cultivars grown in Korea. The wide use of the crop growth models would be facilitated by approaches to extend spatial availability of reliable weather data, which could be either measured on-site or estimates using spatial interpolation. New approaches for calibration of cultivar parameters for new cultivars would also help lower hurdles to crop growth models.

• Journal of the Korean Society of Costume
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• v.39
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• pp.139-166
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• 1998

This dissertation is to help understanding about the emergence of active children's clothes in the latter part of the 18th century in England. In previous ages children had not been look-ed upon as children, but as incomplete and in-ferior men and women, the costume of children had not been distinguishable from that of their elders. The early eighteenth-century chil-d could not play in comfort because they dressed like their parents. But in the third quarther of the eighteenth century children became free from their con-comfortable and became active. English chil-dren's clothes was prevailing even in Europe as well. In the background of this liberation, there were many enlightened ideas, such as philosophers of enlightenment, doctors, writers, educators. Among these John Locke and Jean Jacque Rousseau criticized openly about rampant fashion which was distorting the body by corset and hoop. Rousseau was the one who wrote$\boxDr$Emile$\boxUl$and played the most important role to free children from an old fashioned idea, and emphasized to bring up children by the natural process of mental and physical development as human beings are a part of nature. Fashion reflects politic, economic, social, ideology, culture of the days and these factor function to create fashion which shows“Time Spirit”.Children's clothes, like those of their parents, follow the fashion, but with a difference, the form of which varies with the attitude to the child. Thus this dissertation was to study in relation with the background of the times in the latter part of 18th century in England and Rousseau's Naturalism in connection with the emergence of active children's clothes. The result is that diffusion of the idea of freedom and equality, the growth of bourgeoisie, the development of clothing and tex-tile industry have influenced to the emergence of active children's clothes. Also a great deal of middle and high class parents devoted to their children's education and was influenced by Rousseau's Naturalism. Specially the bourgeoisie who made their fortune by their own effort were eager to educate their achievement and business by their children through education. This factor influenced to the children's clothes as well.

• Journal of Environmental Science International
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• v.25 no.7
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• pp.973-987
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• 2016

The spatial and temporal variations of $CO_2$ concentrations and radiative forcing (RF) due to $CO_2$ were examined at urban center (Yeon-dong) during 2010-2015 and background sites (Gosan) during 2010-2014 on Jeju Island. The RF at the two sites was estimated based on a simplified expression for calculating RF for the study period. Overall, annual mean $CO_2$ concentrations at the Yeon-dong and Gosan sites have gradually increased, and the concentrations were higher at Yeon-dong (401-422 ppm) than at Gosan (398-404 ppm). The maximum $CO_2$ concentrations at the two sites were observed in winter or spring, followed by fall and summer, with higher concentrations at Yeon-dong. The RF at Yeon-dong (annual mean of up to $0.70W/m^2$ in 2015) was higher than that at Gosan (up to $0.46W/m^2$ in 2014), possibly because of higher $CO_2$ concentrations at Yeon-dong resulting from population growth and human activities (e.g., fossil fuel combustion). The highest monthly mean RFs at Yeon-dong (approximately $0.92W/m^2$) and Gosan ($0.52W/m^2$) were observed in spring 2015 (Yeon-dong) and spring 2013 (Gosan), whereas the lowest RFs (0.17 and $0.31W/m^2$, respectively) in fall 2011 (Yeon-dong) and summer in 2012 (Gosan).

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.4
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• pp.573-585
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• 1996

This study of counter-culture - the cultural background of the Jean Fashion of which express the consciousness and youthfulness of young - shows the various social, cultural developments and the direction of growth for the Jean industry Until now, the fashion trends flowed from the elite, upper-class minority to the general public : however, in the case of the Jean Fashion, it has spread inversely to the upper-class from the young people who have adopted the life-styles of the lower, middle class, working people. With the emphasis on Jean Fashion's establishment through and within a counter- culture influences, the first chapter explores the counter-culture's background theory and how fashion has metamorphisized within the counter-culture. The second chapter explores the image of the jeans within the society of the youth and the general public. Finally in the fourth chapter, this study divides the images of Jean Fashion within the youth and the general population into classifications of Feminism, Eroticism, Dismantlementation. Thus, 1 came to the conclusion that the above stated theories have had great influence on the Jean Fashion Industry. The conclusion of this study are as follows: 1 Jeans are the representative article of clothing of unisex appeal which is the core characteristic of Feminism. Feminism, which surfaced coincidentally with the emergence of jeans in the 1850s, took charge of expressing the freedoms and the wills of women. 2. Jeans, being the representative article of Eroticism, have firmly entrenched its image in the young people's wardrobe through mass media such as movies, $\mu$ic, and commercials. 3. In the 90s the tendencies of Defacement and Dismantlementation of Jeans developed. In the Dismantlement tendencies of colors, the color blue foretells of the century's coming to an end, and blue also expresses the superiority of spirit and intelligence which transcends materialism.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.208-208
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• 2010

Zinc oxide (ZnO) is a functional material with interesting optical and electrical properties, a wide band gap (more than 3.3 eV), a high transmittance in the visible light region, piezoelectric properties, and a high n-type conductivity. This material has been investigated for use in many applications, such as transparent electrodes, blue light-emitting diodes, and ultra-violet detector. ZnO films grown under low oxygen pressure by thin film deposition methods show low resistivity and large free electron concentration. Therefore, reducing the background carrier concentration in ZnO films is one of the major challenges ahead of realizing high-performance ZnO-based optoelectronic devices. In this study, we deposited ZnO thin films on sapphire substrates by pulsed laser deposition (PLD) with employing an oxygen plasma source to decrease the background free-electron concentration and enhance the crystalline quality. Then, the substrate temperature was varied between 200 'C to 900 'C The vacuum chamber was initially evacuated to a pressure of $10^{-6}$ Torr, and then a pure $O_2$ gas was introduced into the chamber and the pressure during deposition was maintained at $10^{-2}$ Torr. Crystallinity and orientation of ZnO films were investigated by X-ray diffraction (XRD). The film surface was analyzed with atomic force microscope (AFM). And electrical properties were measured at room temperature by Hall measurement.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.9
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• pp.1185-1190
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• 2018

As a countermeasure to the increasing workforce diversity worldwide, this study addresses the need for an ICT (information communication technology) based diversity management function and identifies the role of e-HRM (electronic-human resource management), which enables this function. ICT has essential for the survival and growth of a company. And it is strategically crucial to recruit and manage a workforce efficiently that comprises individuals not only with diverse demographic backgrounds in terms of gender, race, and age, but also with diverse personal history in terms of educational background, functional background, and the number of years working at a previous job, because these are directly related to organizational performance. Based on the fact that only the organizations that utilize ICT adequately in managing diversity can gain a competitive advantage, this paper discusses the implications of ICT-based diversity management for organizations and managers.

• Archives of design research
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• v.14 no.1
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• pp.119-134
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• 2001

It can be said that Italian designs are unrestrained, aesthetic and art for arts sake, and they come to stylize their character based on geographical features, racial traits and culture. The Italian architects work for the reconstruction of their devastated country and spare no pains to produce competitive goods on international markets since the second wend war. In spite of a inherent scarcity of resources, Italian furniture is the product of mixture of aesthetic material and new material with creative gifts. A lot of companies succeed in finding and training capable designers and devote themselves to modem furniture industry. As a result, Italy becomes one of the worlds most eminent furniture industrial countries now. And the fame is owed to Italy's national awareness of the importance of the matter and endeavor without sparing systematic support. This research is to find out which factors have an influence on the progress of furniture design in Italy and to analyze how these factors build up formative arts combining with historical background in Italy. Moreover, this research suggests how to make contributions to the cause of furniture design growth when considering our geographical features, racial characteristics, culture and industrial circumstances, by analyzing the process of development and strategy in Italian design industry.

• Nuclear Engineering and Technology
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• v.38 no.7
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• pp.639-656
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• 2006

In order to apply the leak before break (LBB) concept to nuclear piping systems, the dynamic strain aging effect of low carbon steel materials has to be taken into account, in compliance with the requirements of the Korean Standard Review Guide (KSRG) 3.6.3-1. For this goal, J-R tests are needed for a range of various temperatures and loading rates, including dynamic loading conditions. In the dynamic loading J-R test, the unloading compliance method can not be applied to measure the crack growth and direct current potential drop (DCPD) method; this method also has a problem defining the crack initiation point. The normalization method is known as a very useful method to determine the J-R curve under dynamic loading because it does not need additional equipment or complicated loading sequences such as electric current or unloading. This method was accepted by the American Society for Testing and Materials (ASTM) as a standard test method E1820 A15 in 2001. However, it has not yet been clearly verified yet if the normalization method is sufficiently reliable to be applied to LBB. In this study, the basic background of the J-integral, LBB and dynamic loading J-R test are explained, and the current status for dynamic loading J-R test methods are reviewed from the view point of LBB for nuclear piping. In particular, the theoretical and historical background of the normalization method which has received attention recently, is summarized. Recent studies for this method are introduced and future works are suggested that may improve the reliability of LBB for nuclear piping.