• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.5
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• pp.200-204
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• 2008

Mechano Chemical Process (MCP) skips the calcinations steps at an intermediate temperature that is always required in the conventional solid-state reaction because forming phase from raw powder is activated by mechanical energy. In this study, we prepared (Pb, La)$TiO_3$ nanopowder with perovskite structure by only high energy MCP. Especially, the PLT nanopowder was synthesized without any thermal treatment using oxides, not salts as raw powder. This process is also very simple due to dry milling method, unnecessary to dry of powder. The oxide powder was milled up to 12 hr at intervals of an hour using MCP and the pure PLT phase of perovskite structure was formed after milling time of 3 hr. And the average particle size was 20 nm with narrow distribution after milling time of 3 hr from raw powder of several $\mu m$ with inhomogeneous distribution.

• Journal of the Korean Society of Earth Science Education
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• v.13 no.1
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• pp.100-109
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• 2020

This study aimed to develop a 'star-car' operational program combining with the STEAM program and the PEST method for motivating elementary school students who belonged to less favored areas in terms of scientific culture to get an interest in astronomy and appropriately forming scientific concepts of Astronomy and Space and, subsequently, to examine the effectiveness of the program. For the purposes to be feasible, 5 experts participated in the study. They set a development direction of the program through a workshop, developed a draft with respect to a mobile astronomical observatory program of the Korea Astronomy and Space Science Institute, and then complete the development of the program through one trial application. The program which was developed in the study applied the STEAM program and targeted the elementary school students who lived in isolated regions of the scientific culture. The results of the research were as follows. First, The mobile astronomical observatory program developed in this study was improved as a program which stimulated the curiosity of elementary school students in all grades towards the Astronomy and Space. Second, The program developed in the study consisted of 11 periods in total; one period was for the presentation of the situation, five periods for emotional experience, the other five periods for creative design. Third, The results of analyzing the students' satisfaction were turned out to be effective in general. Judging from the aforementioned results, the mobile astronomical observatory program is expected to enhance learners' core competencies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.192-198
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• 2016

The purpose of this study was to determine the relationship between the brand and awareness of the brand image relationship in a catering company in Gwangju quality(trust, satisfaction). Twenty adults aged 20 years or older residing in Gwangju were surveyed after setting a hypothesis as a convenience sampling method in order to achieve the research objectives via extraction of the sample survey and empirical analysis. Customers using the brand image of catering companies in a relationship significantly affected the quality of the relationship (trust) forming symbolic images, but the images that were empirically related significantly to the trust did not form a significant relationship for trust. Brand image quality significantly impacted the relationship(satisfaction) that is the symbolic image of relations forms a significant relationship between satisfaction. Empirically, however, the image did not form a significant relationship for satisfaction. Brand recognition is significant in relationship quality(trust) and a significant relationship brand recognition, as it has formed a significant relationship on trust. Brand recognition is the quality of the catering companies using the customer significant effect on the relationship (satisfaction) relationship of brand recognition was formed a significant relationship satisfaction. As a result, the catering company's brand image, brand perception and empirical validation suggested a relationship between the quality of the relationship that provided very significant implications in this regard. In the future, overcoming the limitations of this study will necessitate conducting a more in-depth and detailed study.

• Composites Research
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• v.31 no.3
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• pp.88-93
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• 2018

In this study, damaged composite laminates were repaired by a stepped patch repair method using halloysite nanotube(HNT) and milled carbon(MC) reinforced composite materials with different amount of the particles. And the mechanical and structural effects of the particles on the interface between the damaged and repair surfaces were analyzed. At this time, after exposing them to a harsh environment of high temperature and humidity for a long time, the recovery rate of the material properties relative to the material forming the damaged plate was compared. As a result, at $70^{\circ}C$ high temperature distilled water, the hygroscopicity of the HNT/GFRP composites was significantly different from that of the MC/GFRP composites. Especially, 0.5, 1 wt. % HNT was added, the moisture absorption rate was the lowest and this was the factor that contributed to the mechanical strength increase. On the other hand, MC showed a high hygroscopic resistance only with a small amount, and the strength was different according to the action direction of the load, and the addition amount was also different.

• Journal of the Korean Chemical Society
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• v.46 no.1
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• pp.7-13
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• 2002

Although it has been known that the magnetized water shows different physicochemical properties, the exact nature of the magnetized water is not clearly elucidated yet. We have explored the effect of magnetized water in the precipitation of salts, i.e., $BaSO_4,\;BaCO_3,\;CaCO_3$, and in the hydration hardening of gypsum plaster. The amount of salt precipitation was measured by salt filter assay in water bath, $25^{\circ}C$ and also the hydration hardening speed of gypsum plaster was measured by the Gillmore needle method at room temperature. When the salt ions were interacted with each other in 0.1 M concentration, the precipitation reactions of $BaSO_4,\;BaCO_3$, and $CaCO_3$ increased more in the magnetized water, about 3.6%, 3.8%, and 4.4%, respectively, than in the control water. And the hydration hardening speed of gypsum plaster increased more in the magnetized water than in the control water. These data suggest that the magnetized water, which is supposed to be organized by forming numerous nano/micro clusters, induces the increase of salt precipitation and also accelerates the hydration hardening speed of gypsum plaster.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.291-298
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• 2008

Methylmercury, an organic derivative, is the principal form of mercury that biomagnifies and causes neurodegenerative symptoms in animals. In recent years, living modified organism (LMO) resulting from biotechnology has played a highly visible and controversial role. Despite the potential benefits of this technology, public concerns have been raised about the environmental risk of LMO. The concern on the risk from LMO release has urged efforts to evaluate and manage the risks of the LMO. To build up the capacity building of risk assessment method for LMO used environmental remediation, we engineered Solanum nigrum L, expressing the modified bacterial gene, merB, encoding organomercurial lyase. Two independently isolated transgenic lines produced merB RNA. Transgenic Solanum nigrum leaf discs expressing merB gene showed organic mercury resistance, forming shoots well on growth medium containing $0.5{\mu}M$ methylmercury (II) chloride and $1{\mu}M$ phenylmercuric acetate while control plants breached. Transgenic merB seeds germinated and grew on growth medium containing $2{\mu}M$ methylmercury (II) chloride and phenylmercuric acetate. The merB transgenic plants will be used for risk assessment of natural environment.

• Korean Journal of Human Ecology
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• v.19 no.1
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• pp.149-156
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• 2010

TV news anchor woman's appearance, voice, expression, and clothing, etc., have an influence on the reliability of the article to be reported. Among these, clothing is the most crucial factor in forming an anchor woman's image, especially the clothing color factor. This study is aimed at providing the basic foundation for anchor woman when they select the clothing color by analyzing the clothing color image on the screen. For this purpose, the KBS and MBC 9 o'clock news desk and SBS 8 o'clock news of the local major news programs were selected. With the collection of 300 pieces of news clips related to anchor woman's clothing from January to December 2008, they were classified into F/W seasons and analyzed by the clothing color. The surveying method of clothing color was to capture the anchor woman's clothing among the news clips, then pick the representing color by applying Adobe Photoshop, and researching the formed $L^*a^*b^*$ value of color chips. The surveyed color was transformed into value of distant cell, H V/C, and the results were analyzed. As a result, it showed that the White system for anchor woman's clothing during the S/S seasons is most frequently picked, followed by the Red system. In F/W seasons, Gray system is the most favored, then White and Red, respectively. It was revealed that the most frequently selected colors for upper-wear by anchor women in the three broadcasting stations was an achromatic color, such as White or Gray, and then the chromatic color, Red. It shows that there is no big difference in season. The Inner-wear color matched the jackets which were also achromatic in color, white and black being the most favored in the S/S seasons, and in the case of chromatic colors, Red was the most favored. In addition to this, identical coloration with jacket, coloration with similar color, or single color as clothing color were no less frequently adopted. During the F/W seasons, identical coloration accounts for 26%, the most popular colored being White and Red. It was found that the coloration with achromatic colors are highly favored in the three major broadcasting stations alike.

• Journal of Biomedical Engineering Research
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• v.28 no.2
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• pp.306-309
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• 2007

PXLM(Phosphor based x-ray light modulator) has a combined structure by phosphor, photoconductor, and liquid crystal and it can realize x-ray image of high resolution in clinical diagnosis area. In this study, we fabricated a photoconductor and investigated electrical and optical properties to confirm application possibility of radiator detector of PXLM structure. As photoconductor, amorphous selenium(a-Se), which is used most in DR(Digital radiography) of direct conversion method, was used and for formation of thin film, it was formed as $20{\mu}m-thick$ by using thermal vacuum evaporation system. For a produced a-Se film, through XRD(X-ray diffraction) and SEM(Scanning electron microscope), we investigated that amorphous structure was uniformly established and through optical measurement, for visible light of 40 $0\sim630nm$, it had absorption efficiency of 95 % and more. After fabricated a-Se film on the top of ITP substrate, hybrid structure was manufactured through forming $Gd_2O_3:Eu$ phosphor of $270{\mu}m-thick$ on the bottom of the substrate. As the result to confirm electrical property of the manufactured hybrid structure, in the case of appling $10V/{\mu}m$, leakage current of $2.5nA/cm^2$ and x-ray sensitivity of $7.31nC/cm^2/mR$ were investigated. Finally, we manufactured PXLM structure combined with hybrid structure and liquid crystal cell of TN(Twisted nematic) mode and then, investigated T-V(Transmission vs. voltage) curve of external light source for induced x-ray energy. PXLM structure showed a similar optical response with T-V curve that common TN mode liquid crystal cell showed according to electric field increase and in appling $50\sim100V$, it showed linear transmission efficiency of $12\sim18%$. This result suggested an application possibility of PXLM structure as radiation detector.

• Research in Community and Public Health Nursing
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• v.10 no.1
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• pp.227-238
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• 1999

The goal of this study is to discover the effect of sex education on sex-related knowledge and attitudes of middle school girls. Non-equivalent control group pretest-posttest design was used. The number of experimental group students was 134 and the number of control group students was 134. A total of 268 second grade middle school girls were selected for a convenience sampling method. This study was carried out in a middle school located in Taegu City, Korea, from February 5 to February 18, 1998. To des cover the needs of sex education, the researcher sent a predesigned questionnaire to 1464 girls in 19 different middle schools. The sex education curriculum was designed on the basis of this survey's results. 'The Sex Education Teaching Plan' (published by the Research Institution of Korean School Health Education) and 'Sex and Happiness' (published by the Seoul City Education Ministry) were used to redesign the sex education curriculum and content. Fifty minute long sex education classes were taught to the experimental group every other day and the total number of classes was five. The contents of the teaching -learning plan for sex education were: 'The Characteristics of Adolescence', 'Pregnancy and Contraception', 'Friendship with the Opposite Sex and Prevention of Sexual Violence', 'Prevention of Venereal Disease', and 'Sex and Society'. To measure the degree of sex knowledge of the subjects, the researcher used the modified sex knowledge tools of Kim(l995) and Han(1997). The reliability values of these sex knowledge tools range from 0.71 to 0.74, using Cronbach's alpha. To measure the degree of sex attitude in the subjects, the researcher used the modified sex attitudes tools of Han(l997). The reliability values of these sex attitude tools range from 0.73 to 0.78 using Cronbach's alpha. The PC-SAS package program was used to analyse the data along with Frequency, Percentage, XLtest, t -test, and a paired t -test The results of this study were as follows; 1. The first hypothesis was accepted. The experimental group showed more change in sex - related knowledge than the control group(t =22. 76, p=0.0001). 2. The second hypothesis was accepted. The experimental group showed more change in sex-related attitudes than the control group (t=11.91, p=0.0001). In conclusion, the level of sex-related knowledge and sex-related attitudes of middle school girls who received sex education was higher than that of the girls who did not receive sex education. According to this research, planned sex education was effective in forming accurate knowlege and appropriate attitudes related to sex. Clearly, we must carry out a well-designed step by step sex education program that is well-suited to the sex education needs and the developmental level of the students.

• Journal of Environmental Science International
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• v.14 no.9
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• pp.817-825
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• 2005

The purpose of this study was to research about salt marsh flora and vegetation in the Dongjin-river estuary area where has a project for Sea Man Geum Reclaimed Land so that we can foster foundation on restoration of an ecological habitat, development of applicable plant and establishment of a conservation policy after deceloping the reclaimed land for salt marsh vegetation which has great value ecologically. In conclusion, we was distributed that there are 7 families 21 genera, 25 species, 2 varieties of vascular plant at the Dongjin-river estuary area which have 27 taxa in total and are $0.64\%$ among 4,191 of korean vascular plant. There are also 2 family, 2 genus, 2 species of a naturalized plant which are $1.1\%$ of indicator of a naturalized plant salt marsh vegetation of the downstream are very much affected by the time of inundation, tidal water so that a low degree of salt marsh has frequent flooding by sea water and has a pure group of Suaeda japonica. A Phragmites communis, Carex scabrifolia are distributed mainly around a waterway of salt marsh and Zoysia sinica, Atriplex subcordata, Phragmites communis are living in stock as forming into patch around medium salt marsh. Suaeda asparagoides, Phacelurus latifolius are living around a little high ground and a Phragmites communis is a behind vegetation of Phacelurus latifolius and a part of the Phragmites communis are living along with waterway in a salt marsh as a community. By the 2-M method twelve plant communities were recognized ; Suaeda japonica. Carex scabrifolia, Zoysia sinica, Artemisia scoparia, Phacelurus latifolius, Phragmites communis, Suaeda maritima, Suaeda japonica-Atriplex gmelini, Phragmites communis-Suaeda japonica, Suaeda japonica-Salicornia herbacea, Salicornia herbacea-Suaeda aspar-agoides and Scirpus planiculmis community. The actual vegetation map was constructed on the grounds of the communities classified and other data.