• Journal of the Korean Society of Earth Science Education
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• v.10 no.2
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• pp.173-184
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• 2017

The purpose of this study is to examine the effects of science classes using the geological materials of a locality on academic achievement and scientific attitude of elementary school students. For this study, the class unit is 'stratum and fossils', 2nd semester of 3rd grade, and the geological materials of a locality is applied for class. The geological materials used in teaching and learning of 'stratum and fossil' unit are photographs & video data relating to geological phenomenon, and rock & fossils samples collected in Jeollanam-do province. This study has been aimed at 2 classes 47 students of 3rd grade in G elementary school of G metropolitan. One class 23 students are the research group to apply science class using the geological materials in a locality, on the order hand another class 24 students are the comparison group to apply general science classes. The results of this study are follows. First, a positive relationship was identified between academic achievement and science class applying the geological materials in a locality in the research group. This shows that academic achievement was improved by science class applying the geological materials in a locality. Second, a positive relationship was identified between scientific attitude and science class applying the geological materials in a locality in the research group. This shows that scientific attitude was improved by science class applying the geological materials in a locality. Third, by the results of interview with students who was participated in science class applying the geological materials in a locality, it shows that they have interest and curiosity about local geology. Above results means that science class applying the geological materials in a locality help elementary schools students improve the educational effect about 'stratum and fossils' unit. Thus, it is needed to use the geological materials of a locality in science class relating to the geology units of elementary school science in order to improve academic achievement and scientific attitude of elementary school students.

• Journal of The Korean Association For Science Education
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• v.38 no.4
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• pp.495-504
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• 2018

This study was conducted to develop items to measure scientific core competency based on statements of scientific core competencies presented in the 2015 revised national science curriculum and to identify the validity and reliability of the newly developed items. Based on the explanations of scientific reasoning, scientific inquiry ability, scientific problem-solving ability, scientific communication ability, participation/lifelong learning in science presented in the 2015 revised national science curriculum, 25 items were developed by five science education experts. To explore the validity and reliability of the developed items, data were collected from 11,348 students in elementary, middle, and high schools nationwide. The content validity, substantive validity, the internal structure validity, and generalization validity proposed by Messick (1995) were examined by various statistical tests. The results of the MNSQ analysis showed that there were no nonconformity in the 25 items. The confirmatory factor analysis using the structural equation modeling revealed that the five-factor model was a suitable model. The differential item functioning analyses by gender and school level revealed that the nonconformity DIF value was found in only two out of 175 cases. The results of the multivariate analysis of variance by gender and school level showed significant differences of test scores between schools and genders, and the interaction effect was also significant. The assessment items of science core competency based on the 2015 revised national science curriculum are valid from a psychometric point of view and can be used in the science education field.

• Sleep Medicine and Psychophysiology
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• v.10 no.2
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• pp.93-99
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• 2003

Objectives：Sleep loss and excessive daytime sleepiness may have serious consequences, including traffic and industrial accidents, decreased productivity, learning disabilities and interpersonal problems. Yet despite these adverse effects, there are few epidemiological studies on sleep loss and daytime sleepiness in the general population of Korea. This study investigates the number of people who suffer from sleep insufficiency, how much recovery sleep occurs on weekends, and the relationship between the amount of recovery sleep and daytime sleepiness. Methods：A total 164 volunteers, aged 20 and over, were recruited by advertisement. The subjects were workers and college students living in Seoul, Korea. Subjects were excluded if they were aged over 60；if they had medical, neurological, psychiatric or sleep disorders that could cause insomnia or daytime sleepiness；if they were not following a regular sleep schedule；if they traveled abroad during the study；or if they did not leave home to work or were shift workers. They were interviewed and given a sleep log to complete on each of 14 consecutive mornings. They also completed the Epworth Sleepiness Scale (ESS) at noontime on the last day of the second week. All statistical data were analyzed by t-test, $X^2$-test or ANOVA, using SPSS/PC+. Results：The results showed that the subjects woke up at 6：50 (${\pm}1$：16) on weekdays, 7：09 (${\pm}1$：29) on Saturdays, and 8：12 (${\pm}1$：39) on Sundays and holidays. They took more frequent and longer naps on Sundays than on weekdays and Saturdays. The mean sleep duration was 6h 35 min. on week nights, with a mean increase of about 1h on weekends. Only 9.1% of the subjects spent more than 8h in bed on week nights, with 67% spending less than 7h, and 49.4% reported recovery sleep of more than 1h on Sundays. The subjects who reported recovery sleep of more than 2h on Sundays, showed significantly more excessive daytime sleepiness than those who reported less than 30 min (F=2.62, p<.05). Conclusions：These findings suggest that sleep insufficiency and excessive daytime sleepiness are relatively common in Korea, and that the people who get insufficient sleep on weekdays try to compensate for sleep loss with oversleeping and daytime napping on Sundays and holidays. It appeared that daily sleep insufficiency had a cumulative effect and increased daytime sleepiness.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.47-60
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• 2010

Most of the researches about classification usually have used kNN(k-Nearest Neighbor), SVM(Support Vector Machine), which are known as learn-based model, and Bayesian classifier, NNA(Neural Network Algorithm), which are known as statistics-based methods. However, there are some limitations of space and time when classifying so many web pages in recent internet. Moreover, most studies of classification are using uni-gram feature representation which is not good to represent real meaning of words. In case of Korean web page classification, there are some problems because of korean words property that the words have multiple meanings(polysemy). For these reasons, LSA(Latent Semantic Analysis) is proposed to classify well in these environment(large data set and words' polysemy). LSA uses SVD(Singular Value Decomposition) which decomposes the original term-document matrix to three different matrices and reduces their dimension. From this SVD's work, it is possible to create new low-level semantic space for representing vectors, which can make classification efficient and analyze latent meaning of words or document(or web pages). Although LSA is good at classification, it has some drawbacks in classification. As SVD reduces dimensions of matrix and creates new semantic space, it doesn't consider which dimensions discriminate vectors well but it does consider which dimensions represent vectors well. It is a reason why LSA doesn't improve performance of classification as expectation. In this paper, we propose new LSA which selects optimal dimensions to discriminate and represent vectors well as minimizing drawbacks and improving performance. This method that we propose shows better and more stable performance than other LSAs' in low-dimension space. In addition, we derive more improvement in classification as creating and selecting features by reducing stopwords and weighting specific values to them statistically.

• Journal of the Korean Society of School Health
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• v.12 no.2
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• pp.207-215
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• 1999

The objectives of this study are to explain the use of media materials in school health education with other related factors in elementary, middle, and high schools in Korea. The data were collected by questionnaires from June to September in 1998. The number of subjects were 294 school nurses. The PC-SAS program was used for statistical analysis such as percent distribution, chi-squared test, spearman correlation test, and logistic regression. The use of media materials in health education has become extremely common. Unfortunately, much of the early materials were of poor production quality, reflected low levels of interest, and generally did little to enhance health education programming. A recent trend in media materials is a move away from the fact filled production to a more affective, process-oriented approach. There is an obvious need for health educators to use high-quality, polished productions in order to counteract the same levels of quality used by commercial agencies that often promote "unhealthy" lifestyles. Health educators need to be aware of the advantages and disadvantages of the various forms of media. Selecting media materials should be based on more than cost, availability, and personal preference. Selection should be based on the goal of achieving behavioral objectives formulated before the review process begins. The decision to use no media materials rather than something of dubious quality usually be the right decision. Poor-quality, outdated, or boring materials will usually have a detrimental effect on the presentation. Media materials should be viewed as vehicles to enhance learning, not products that will stand in isolation. Process of materials is an essential part of the educational process. The major results were as follows : 1. The elementary schools used the materials more frequently. But the production rate of media materials was not enough. The budget was too small for a wide use of media materials in school health education. These findings suggest that all schools have to increase the budget of health education programs. 2. Computers offer an incredibly diverse set of possibilities for use in health education, ranging from complicated statistical analysis to elementary-school-level health education games. But the use rate of this material was not high. The development of related software is essential. Health educators would be well advised to develop a basic operating knowledge of media equipment. 3. In this study, the most effective materials were films in elementary school and videotapes in middle and high school. Film tends to be a more emotive medium than videotape. The difficulties of media selection involved the small amount of extant educational materials. Media selection is a multifaceted process and should be based on a combination of sound principles. 4. The review of material use following student levels showed that the more the contents were various, the more the use rate was high. 5. Health education videotapes and overhead projectors proved the most plentiful and widest media tools. The information depicted was more likely to be current. As a means to display both text and graphic information, this instructional medium has proven to be both effective and enduring. 6. An analysis of how effective the quality of school nurse and school use of media materials shows a result that is not complete (p=0.1113). But, the budget of health education is a significant variable. The increase of the budget therefore is essential to effective use of media materials. From these results it is recommended that various media materials be developed and be wide used.

• Korean Journal of Social Welfare
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• v.57 no.3
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• pp.223-249
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• 2005

This study examines the hazard rate of reemployment by conducting the Cox regression analysis. In addition, two gender groups are subjected to comparative analysis to identify the effect of the factors related to the human capital and human capability perspective on reemployment. For this purpose, 1,871 cases are selected from the 5th year data from Korea Labor and Income Panel Study. The results of study are as follows. First, the factors of human capital, such as education, appropriateness of skill level, and job tenure hold negative impact on the probability of reemployment, while factors of human capability, such as basic learning ability, health insurance, social insurance, residential area(living in the Seoul metropolitan area) hold positive on the probability of reemployment. It is interesting note that there are different sets of factors that affect the probability of reemployment in the two gender groups. This trend is even more apparent in the case of factors that pertain to human capability. The results of this study imply that the factors of human capability, which stress the socio-institutional characteristics, should be considered as comparably significant compared to the factors that pertain to human capital when it comes to the estimation of reemployment. Also, results of this comparative study teach us that various perspectives, such as dual labor market theory and gender-segmented labor market theory, should be factored in for reemployment discussion as well. In conclusion, this research delivers several significant messages since it introduces the concept of human capability perspective, subjected to few empirical analyses in the past, and also heralds the way for comparative analysis on the impact of the factors pertaining to human capability on reemployment.

• Journal of Korean Home Economics Education Association
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• v.23 no.1
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• pp.159-176
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• 2011

The purpose of this study was to investigate 1) how the middle school Home Economics teachers perceive the importance of the practical problem-focused instruction, 2) how often they perform the instruction, and 3) what they require for the implementation the instruction. Data were collected from 150 Home Economics teachers via e-mail survey and from 6 Home Economics teachers' face-to-face interviews. Descriptive statistics including frequency, percentage, average, and standard deviation, and the results of such analyses as ANOVA, T-test, and correlation were reported using SPSS/win 10.1. The results of this research were as follows: First, even though the majority of the respondents recognized the high need for practical problem-focused instruction, only a small portion of the respondents reported that they performed that instruction in the classroom. There was no correlation between the perception of the need for practical problem-focused instruction and the degree of performance of practical problem-focused instruction. Secondly, the of performance of practical problem-focused instruction was significantly different depending on the years of teaching experience and the subject that the teachers majored in. Job satisfaction had positive correlations with the perception of the need for practical problem-focused instruction and the degree of performance of practical problem-focused instruction. Thirdly, the more teachers shared information and materials with colleagues, the better they tended to be at practical problem-focused instruction. On the other hand, insufficient time for their instruction and a deficiency in understanding the rationale of the instruction were pointed out as barriers to classroom practice. The respondents answered that long-term training programs on the philosophical foundation of practical problem-focused instruction, materials related to the instruction as well as additional credits for Home Economics are most critical to reduce the discrepancy between the teacher perception and the classroom practice of practical problem-focused instruction.

• 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%).

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.6
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• pp.807-815
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• 2012

This study was carried out to investigate the factors affecting the dietary adaptation of female immigrants in multi-cultural families in Busan. The survey was conducted from October 10 to November 30, 2010 using questionnaires, and the data was analyzed using the SPSS program. The subjects were mainly from China (58.8%), Vietnam (14.7%), Philippines (8.8%) and Japan (7.4%). The longer they had resided in Korea, the lower their preference they had for Korean foods. There were no significant differences in preference according to their nationality. The subjects reported that their consumption of cereals (36.7%), meats (40.0%), fish (50.8%), milk and dairy products (47.4%), vegetables (48.3%), fruits (44.8%), fat and oil (29.1%) and beverages (32.8%) were increased after immigration. They usually obtained information about Korean foods from family (26.5%) and television and internet (26.5%). Sixty four point seven percent of the females ate 'everyday' Korean foods and 30.9% ate their home country foods every day. A higher will for learning Korean foods, intake frequency and age resulted in a higher adaptation of Korean dietary life. Lower marital conflict resulted in higher adaptation. These results suggest that it would be effective to provide systematic nutrition education program for female immigrants and their families to adapt to Korean dietary life.

• The Korean Journal of Nuclear Medicine
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• v.38 no.1
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• pp.21-29
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• 2004

Purpose: Much evidence suggests long-term cigarette smoking alters coronary vascular endothelial response. On this study, we applied nonnegative matrix factorization (NMF), an unsupervised learning algorithm, to CO-less $H_2^{15}O-PET$ to investigate coronary endothelial dysfunction caused by smoking noninvasively. Materials and methods: This study enrolled eighteen young male volunteers consisting of 9 smokers $(23.8{\pm}1.1\;yr;\;6.5{\pm}2.5$ pack-years) and 9 nonsmokers $(23.8{\pm}2.9 yr)$. They do not have any cardiovascular risk factor or disease history. Myocardial $H_2^{15}O-PET$ was performed at rest, during cold ($5^{\circ}C$) pressor stimulation and during adenosine infusion. Left ventricular blood pool and myocardium were segmented on dynamic PET data by NMF method. Myocardial blood flow (MBF) was calculated from input and tissue functions by a single compartmental model with correction of partial volume and spillover effects. Results: There were no significant difference in resting MBF between the two groups (Smokers: 1.43 0.41 ml/g/min and non-smokers: $1.37{\pm}0.41$ ml/g/min p=NS). during cold pressor stimulation, MBF in smokers was significantly lower than 4hat in non-smokers ($1.25{\pm}0.34$ ml/g/min vs $1.59{\pm}0.29$ ml/gmin; p=0.019). The difference in the ratio of cold pressor MBF to resting MBF between the two groups was also significant (p=0.024; $90{\pm}24%$ in smokers and $122{\pm}28%$ in non-smokers.). During adenosine infusion, however, hyperemic MBF did not differ significantly between smokers and non-smokers ($5.81{\pm}1.99$ ml/g/min vs $5.11{\pm}1.31$ ml/g/min ; p=NS). Conclusion: in smokers, MBF during cold pressor stimulation was significantly lower compared wi4h nonsmokers, reflecting smoking-Induced endothelial dysfunction. However, there was no significant difference in MBF during adenosine-induced hyperemia between the two groups.