• Journal of the Korean Geotechnical Society
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• v.20 no.7
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• pp.141-158
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• 2004

The dependency of criteria used to terminate compatibility tests on the prehydration and quality of bentonite in geosynthetic clay liners (GCLs) is evaluated based on permeation with chemical solutions containing 5, 10, 20, 50, and 100 mM calcium chloride ($CaCl_2$). The hydraulic conductivity tests are not terminated before chemical equilibrium between the effluent and the influent chemistry has been established, resulting in test durations ranging from < 1 day to > 900 days, with longer test durations associated with lower $CaCl_2$ concentrations. The evaluation includes both physical termination criteria (i.e., volumetric flow ratio and steady hydraulic conductivity based on ASTM D 5084, ${\ge}2$ pore volumes of flow, constant thickness of specimen) and chemical termination criteria requiring equilibrium between influent and effluent chemistry (viz., electrical conductivity, pH, and $Ca^{2+}\;and\;Cl^-$ concentrations). For specimens permeated with 5, 10, and 20 mM $CaCl_2$ solutions, only the criterion based on chemical equilibrium in $Ca^{2+}$ concentration correlates well with equilibrium in hydraulic conductivity, regardless of prehydration or quality of bentonite. However, all of the termination criteria, except for the volumetric flow ratio and 2 pore volumes of flow for the prehydrated specimens, correlate well with equilibrium in hydraulic conductivity regardless of prehydration or quality of bentonite when permeated with 50 and 100 mM $CaCl_2$ solutions. The results illustrate the uniqueness of the termination criterion based on solute concentration equilibrium between the effluent and the influent with respect to both prehydration and quality of bentonite in the GCLs.

• Journal of Korean Home Economics Education Association
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• v.28 no.2
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• pp.95-111
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• 2016

This study investigated the descriptive statistics and correlation among self-identity, school violence experience, and family social capital of adolescents and examined influence of school violence experience on self-identity and moderating effect of family social capital on the relationship between school violence experience and self-identity. Data used for analysis was from 7th grade students in The Korean Children and Youth Panel Survey in 2012. Analyses were performed using the IBM SPSS program for demographic analysis, pearson correlation, and stepwise regression analyses. Results of the study were as follows: First, the average was slightly higher for self-identity, parents' affectionate attention, and awareness of their child's friends; the average was lower for misconduct experience and victimization experience; second, there was a weak negative correlation between self-identity and bully victimization; there was a positive correlation between self-identity and family social capital (parents' affectionate attention and awareness of their child's friends). Third, to investigate the effect of school violence experience (bullying and bully victimization) on self-identity, stepwise regression analysis results were as follows: Bullying had a statistically positive influence on self-identity and bully victimization had a statistically negative influence on self-identity; both parents' affectionate attention and awareness of their child's friends had a statistically positive influence on self-identity; fourth, parents' affectionate attention had a statistically negative moderating effect on the self-identity; therefore, it signifies that the relationship between bully victimization and self-identity appears differently depending on the parents' affectionate attention, which means that the parents' affectionate attention had a negative effect on the self-identity of the adolescents who were victimized by school violence.

• Journal of Korean Home Economics Education Association
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• v.25 no.1
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• pp.79-94
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• 2013

In this study, the teaching-learning materials and the plan using persimmon juice dyeing, which is one of the traditional natural dyeing methods of Korea, were developed for the purpose of inspiring further awareness of our traditional clothing life-culture. A questionnaire was designed to make a survey on the educational effect, and t-test and Kruscal-Wallis test were conducted to test the significant differences between pre- and post-lessons. A correlation analysis between culture awareness and its education awareness was also done. These prototypes were applied to high school Technology Home Economics classes under the theme, 'Making living goods with persimmon juice dyed fabrics'. Examining the changes in students' awareness of traditional images, and changes in their interest and attitude towards learning in those classes led to the following results. First, as a result of applying LT cooperative learning in order for an understanding of the formation of clothing life-culture and the process of persimmon juice dyeing, many original handicrafts with modern sense were created. Second, a comparative analysis between pre- and post-lessons on the change in students' degree of awareness of traditional clothing life-culture and its education showed that students' awareness had risen after the class; the data was collected from three separate sample groups which had been clustered according to their initial degree of awareness, i.e. high, middle, and low, and the group that scored the lowest before the class showed the greatest improvement. Third, feedback surveys on 'Making living goods with persimmon juice dyed fabrics' classes returned with scores greater than 'moderate', thus revealing that the students' concern and interest towards traditional clothing life-culture hae been enhanced through the class experience. Their attitude had also become more positive. Fourth, since learners with more awareness of the traditional clothing life-culture also showed more awareness of the need for an education designed to promote the culture, a positive correlation between the two had been found. As explained above, the teaching-learning materials and the plan that had been developed for this study has caused a deeper understanding of the value and significance of the traditional natural dyeing and clothing life-culture, and has therefore brought about an educational effect that powers idea creation.

• Journal of Korean Home Economics Education Association
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• v.25 no.3
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• pp.19-38
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• 2013

This study focuses on the differences in general self-concept, academic self-concept, significant others self-concept and emotional-physical self-concept in relation to appearance management behavior. It goes on to show that appearance management behaviors such as styles in clothing, makeup, skin care, hair care, cosmetic surgery and body shaping, weight control management are strongly influenced by self-concept. Therefore, this study was carried out with the aim of providing basic understanding and information on the appearance management behavior of middle school students. It was also done in an effort to find ways of improving the self-concept of students through education as a part of the domestic science curriculum. The results obtained in this study are as follows: On average, the middle school students who took part in this study showed low self-concept and appearance management behavior which indicates a negative image of themselves. This suggests that efforts need to be made so that students can see themselves in a positive way and improve their self-concept through appearance management behavior. Middle school students with a positive self-concept try to present themselves by keeping their skin clean and their hair attractive. They express their self-esteem and personality through fashion and by keeping and maintaining their clothing, shoes and bags. They also tend to show a positive attitude towards their studies and are more likely to understand and get along with others. The students who showed positive attitudes towards their bodies and emotions have a higher interest in clothing and try to express the image that they want for themselves. They are also less likely to change their bodies unnaturally through cosmetic surgery and body shaping. Appropriate appearance management behavior can help middle school students see themselves in a more positive way.

• Journal of Korean Home Economics Education Association
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• v.32 no.3
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• pp.81-96
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• 2020

This study aims to identify implications for the role of home economics in consumer education in middle schools focusing on building consumer competency. To this end, the content in middle school textbooks of home economics and other subjects, written according to the 2015 revised curriculum, were analyzed. This study examined consumer education content based on the consumer competency measurement index developed by the Korean Consumer Agency, and reviewed different foci presented by subjects. This study also investigated how the knowledge, attitude and practice, which are components of consumer competency, are presented. The major findings of this study can be summarized as follows: First, consumer competency content, presented in textbooks of home economics and other subjects, were comprised of citizenship competency(65.3%), transactional competency(27%), and financial competency(7.7%). Second, in terms of content on the consumer's citizenship competency, little attention was paid to consumer rights, revealing an imbalance between responsibilities and rights. Third, despite its importance, the "utilization of information and communications technology" in transaction competency, and "consumer participation" in citizenship competency are insufficiently covered in the home economics. Fourth, social studies was the subject that most extensively covered the content of consumer competency. In terms of scope, home economics dealt with most of the sub-fields. Fifth, even when the same content of consumer competency was covered, it was presented differently by subject. Sixth, there was a lack of connection between components of consumer competency-knowledge, attitude, and practice, with a disproportionately high emphasis on knowledge. In conclusion, this study concluded that consumer education content of middle school subjects is insufficient to enhance consumer competency.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.2
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• pp.120-125
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• 2016

Purpose: The purpose of this study is to identify the effect of mesenchymal stem cell proliferation on recombinant human transforming growth factor-beta (rhTGF-${\beta}2$) / poly (D,L-lactide-co-glycolide) (PLGA) treated titanium discs by electrospray. Materials and methods: Anodized titanium surface coated with PLGA was used for a control group to compare anodized titanium surface coated with 125 ng/ml and 500 ng/ml rhTGF-${\beta}2$ as test groups. Atomic force microscope (AFM) test was utilized to determine the difference in coating surface roughness, and field-emission scanning electron microscopy (FE-SEM) was taken to visualize even distribution of coating particles on titanium discs. The mesenchymal stem cell proliferation was tested by using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl-tetrazolium bromide) assay on 1st, 4th, 7th days. Results: According to AFM results, there was no statistically significant difference in titanium discs treated with PLGA and with rhTGF-${\beta}2$/PLGA (P>.05). MTT assay test results showed that there was statistically significant difference in mesenchymal stem cell proliferation on test groups compared to control groups at 7th day, and cell viability on discs coated with rhTGF-${\beta}2$ was significantly higher than control groups (P<.05). Conclusion: Titanium surface coated with rhTGF-${\beta}2$/PLGA shows statistically significant higher cell proliferation and the titanium surface coated with the higher concentration of rhTGF-${\beta}2$ presents faster cell growth activity.

• Journal of The Korean Association For Science Education
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• v.33 no.4
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• pp.826-839
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• 2013

The purpose of this study is to examine science education researchers' views on what and how much science educational theories would be needed for pre-service science teachers, and to investigate the relationship between their views and the Examination for Appointing Secondary School Science Teachers(EASST). For this study, the views of science education professors on science education theories have been analyzed in terms of their priorities for contributing to the improvement of science teacher competency and literacy. Their views have been compared with proportions of questions related to science education theories of the EASST in terms of what kinds of science education theories have been used for solving each item. As results of this study show, they have perceived that more essential things are needed for the improvement of science teacher competency and literacy including science inquiry process, methods of experimental equipments and tools, laboratory safety, misconception of students, discussion, writing, evaluation of scientific knowledges, and evaluation of scientific inquiry ability other than science philosophy, changes of science curricula, science curricula of foreign countries, Bruner's instructional theory, Karplus's Learning Cycle model, generative learning model, discovery learning model, and Klopfer's taxonomy of educational objectives. There is a higher proportion of questions related to science curriculum and Ausubel's learning theory in the EASST. They are hardly correlated with science education professors' selections of science educational theories for EASST questions. This study advocates the needs of exploring a new method of narrowing down the gap between science educators' opinions and questions of ESSAT in terms of science educaiton theories.

• Journal of Aquaculture
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• v.9 no.1
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• pp.43-55
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• 1996

The experiment was performed to evaluate the possibility of utilizing underground sea water for the seed production of tiger puffer, Takifugu rubripes. For this purpose, the effects of 6 different salinities (3.5, 7.0, 14.0, 20.0, 27.0, $33.0\%_{\circ}$) were determined based on the hatching rate of fertilized eggs, survival rate and the amount of food consumed by hatched larvae, where as the effects of 3 different salinities (20.0, 27.0, $33.0\%_{\circ}$) were also examined with rearing tiger puffer juvenile ($4.29{\pm}0.50$ cm in total length) for 50 days in the closed recirculating water system. As a results, either the hatching or the survival rate of more than $70.0\%$ were obtained from the fertilized eggs reared at the salinity of 27.0 to $33.0\%_{\circ}$, the early hatched larvae at 27.0 to $33.0\%_{\circ}$, and the 10-day-old larvae at 20 to $33.0\%_{\circ}$. At three different salinities, the survival rate of 20-day- and 30-day-old larvae turned out to be $89.0\%$ and $92.5\%$, respectively. The salinity for maximum food intake thus appeared to be from 27.0 to $33.0\%_{\circ}$. In this condition, 20-day-old hatched larvae consumed $323\~342$ Artemia nauplii and 30-day-old hatched larvae ate $1,559\~1,5791$ A. nauplii. The highest growth rate of fingerlings were observed at the salinity $27\%$ and followed by 33.0 and $20.0\%_{\circ}$, respectively. The relationship between the days of rearing (X) and the total length (Y) of the fingerlings were as follows : $33.0\%_{\circ}$ group : Y=0.107X-2.532 (r=0.982) $27.0\%_{\circ}$ group : Y=0.116X-3.195 (r=0.975) $20.0\%_{\circ}$ group : Y=0.116X-2.693 (r=0.987) The slopes of regression line estimated from $27.0\%_{\circ}$ and $33.0\%_{\circ}$ groups were significantly different from that of $20.0\%_{\circ}$ group.

• 대한공업교육학회지
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• v.33 no.2
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• pp.192-217
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• 2008

This paper investigated the perceived criticalities and patterns of Korean Professional Engineer's competency regarding the working activities of automative product development, manufacturing, etc by using questionnaires responded to the survey which were applied to the automotive professors, experts and professional engineers (vocational parties) by e/mail, etc. This research investigated the following questions: First, what are the characteristic patterns, relevancy and perceived criticalities of Korean Professional Engineer's competencies? Second, What are the ranked priority of the Korean Professional Engineers' competencies? Are there any differency for each item, sub group of job, intelectual criterior of the competencies between relevancy and perceived criticalities according to the types of vocational parties, etc.? Accoring to the results; first, Professor group showed highest points among 3 groups per each item of the competencies by vocational parties Second, Chassis design group ranked top position among the 8 sub groups by vocational parties and, third, Problem Solving Knowledge ranked highest points than any others. Korean Professional Engineers are found to be positioned as key members, leaders and managers on surveying market, product planning, designing product & components, developing component parts, establishing shop with production equipment, managing quality control & material handling, organizing relevant meetings, developing human resources by training and learning, to back up finance with law matters, cooperating with concerned parties to achieve organizational goals, and to coordinate projects. etc, identifying ethical issues and business skills in order to survive and win to be competitive in various kinds of the automotive industry battle fields.

• 대한공업교육학회지
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• v.36 no.1
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• pp.75-94
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• 2011

The purpose of this study is to suggest the basic data in order to examine and perform the plan for activating the team teaching between industry-educational adjunct teachers and vocational teachers in technical high school. The research results are as follows. First, It is found that both teacher groups acknowledge the necessity of the team teaching, but vocational teachers are less likely to recognize the necessity than industry-educational adjunct teachers. Second, In the preparation of team teaching, both two groups of the teachers believe that the preliminary interchange and training between them are to be highly supportive for the activities expected to help teachers. Therefore, it is necessary to have opportunity of communication and narrow the difference of opinions between them by promoting the deep interest about applicable field and sharing the mutual idea between the teachers in the preparation of team teaching. Third, And the two groups recognize that the cooperation and joint establishment of design of team teaching and the individual process or joint progress of class activity are desirable for the proper design of team teaching. Therefore, it is necessary to establish the class environment for the interaction between teachers and students through not only the reciprocal activities between teachers but the interest class by systematically preparing the class design and role division clearly. Fourth, In the practice of team teaching, the two groups believe that the teaching activities can be usually divided and progressed, but it is desirable to work together in the related contents. The vocational teachers recognize that it is necessary to actively interact with students by connecting with the case of industry field. On the other side, industry-educational adjunct teachers think that the learning contents should be selected and organized according to the interests of students by associating with the case of industry field. Fifth, And two groups of teachers recognize that it is desirable to evaluate the grade by reflecting on the assessment by vocational teachers(50%), industry-educational adjunct teachers(50%).