• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.11 no.11
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• pp.947-953
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• 1998

The microwave dielectric properties of X BaO-0.15($Nd_{0.87}Bi_{0.13})_2O_3-(0.85-X)TiO_2 (X=0.14~0.17) and 0.16BaO-0.15(Bi_xNd_{1-x})_2O_3-0.69TiO_2$ (X=0.12~0.15) ceramics sintered at 1320~$1380^{\circ}C$ were investigated. The microwave dielectric properties of X BaO-0.15(Nd_{0.87}Bi_{0.13})_2O_3-(0.85-X)TiO_2$ (X=0.14~0.17) can be controlled effectively by adjusting X content : with increasing X from 0.14 to 0.17 both dielectric constant and temperature coefficient of resonant frequency decreased from 94.6 to 86 and from 22 ppm/^${\circ}C to -7 ppm/^{\circ}C$, respectively, while quality factor increased from 1300 to 1920 (at 4GHz). The microwave dielectric properties of 0.16BaO-0.15(Bi_x/Nd_{1-x2}O_3 -0.69TiO_2$ (X=0.12~0.15) can be controlled effectively by adjusting X content : with increasing X from 0.12 to 0.15 both quality factor and temperature coefficient of resonant frequency decreased from 1920 to 1430 and from 9 ppm/^${\circ}C to -10 ppm/^{\circ}C$, respectively, while dielectric constant increased from 87.5 to 92.6.

• Journal of Korean Academy of Nursing
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• v.26 no.2
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• pp.345-358
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• 1996

All human health behavior is deeply rooted one's beliefs or value system usually encompassed within the culture in which they live. The Taegyo, based on Oriental folk medicine, is defined as the behavior and self care of pregnant women administered for herself and her fetus(unborn child). Taegyo is believed to be desirable, effective, and healthy behavior by most of Korean pregnant women. It is essential in our contemporary culture, to ascertain what the components of Taegyo are and to integrate them into current, western nursing care, particularly in the area of prenatal care. 910 Korean women were the subjects of this study, who were in a gestation period of pregnancy between 10 weeks to three months postpartum. The subjects were selected by clustered smpling from 10 representative cities in Korea. Data was collected from February 10 to March 30 1995 by a constructed Questionnaire which consisted of 95 items. The questionnaire was developed through three steps such as content analysis, calculation of content validity index, and pretest. Data was analyzed by descriptive statistics and rotated matrix factor analysis with pc-SAS. The mean age of the subjects was 28.9 years : 36.5％ of them were employed and the mean income per month was about 2000 dollars. The component of Taegyo was clustered into five factors such as fetus psychological stability(equity), fetus personality development, maternal-fetal interaction, fetus intellectual development and physical health promotion. The variance of each factor were 23.7％, 8.3％, 4. 7％, 4.1％, and 3.3％ respectively in that order. The Eigen value of each factor was 13.03, 4.57, 2.60, 2.23, and l.83 respectively. It was found that the Taegyo is an unique and holistic self care behavior of Korean pregnant women. Therefore it has been concluded that this study has broadened the understandability of the implications the Taegyo. It is suggested that further studies on the effects of the Taegyo are needed to provide a scientific basis for professional maternity nursing.

• Analytical Science and Technology
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• v.30 no.4
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• pp.159-166
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• 2017

Exposure to UV light, i.e., UV-A (320-400 nm) or UV-B (290-320 nm) radiation, can cause skin cancer. Titanium dioxide ($TiO_2$) effectively disperses UV light. Therefore, it is used as a physical UV filter in many UV light blockers. Usually, the $TiO_2$ content in commercialized UV blockers is 25 % at most. To block UV-B, a chemical UV blocker, octyl-methoxy cinnamate (OMC) is used. OMC is commonly used in combination with $TiO_2$. In this study, $TiO_2$ and OMC were mixed in different proportions to produce UV blockers with different compositions. Also the changes in the sun protection factor (SPF) based on the composition and $TiO_2$ particle sizes were investigated. In order to analyze the $TiO_2$ particle size, dynamic light scattering (DLS) and asymmetrical flow field-flow fractionation (AsFlFFF) were used. The results showed that the SPF was influenced by the proportion of $TiO_2$ and OMC, where the proportion of $TiO_2$ induced a more significant influence. In addition, changes in the $TiO_2$ particle size based on the proportion of OMC were observed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1227-1232
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• 2014

Background: Given that there are many Iranian women who have never had a Pap smear, this study was designed to develop and validate a measurement tool based on the Protection Motivation Theory to assess factors influencing the Iranian women's intention to perform first Pap testing. Materials and Methods: In this psychometric research, to determine the Content Validity Index (CVI) and the Content Validity Ratio (CVR), a panel of experts (n=10) reviewed scale items. Reliability was estimated through the Intraclass Correlation Coefficient (n=30) and internal consistency (n=240). Also, factor analysis (exploratory and conformity) was performed on the data of the sample women who had never had a Pap smear test (n=240). Results: A 26-item questionnaire was developed. The CVI and CVR scores of the scale were 0.89 and 0.90, respectively. Exploratory factor analysis loaded a 26-item with seven factors questionnaire (perceived vulnerability and severity, fear, response costs, response efficacy, self-efficacy, and protection motivation (or intention)) that jointly accounted for 72.76% of the observed variance. Confirmatory factor analysis indicated a good fit for the data. Internal consistency (range 0.70-0.93) and test-retest reliability (range 0.72-0.96) of sub-scales were acceptable. Conclusions: This study showed that the designed instrument was a valid and reliable tool for measuring the factors influencing the women's intention to perform their first Pap testing.

• Journal of Korea Water Resources Association
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• v.47 no.4
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• pp.321-330
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• 2014

This study was performed to investigate relation between riparian vegetation and environmental factor and to predict riparian vegetation succession in Nakdong river, which is typical sand river in Korea Peninsula. We searched 5 natural levee and installed 84 quadrats in Nakdong river near by Andong city. Also, We analyzed flora, vegetation cover degree, topography, soil moisture, organic content, pH, electrical conductivity and soil texture. According to the result of CCA (canonical correspondence analysis), which considered both investigated vegetation data and environmental factor, vegetation were divided down three groups, and each group was difference by height above ordinary water level, organic content and sand. In addition, the most powerful factor was indicated the height above ordinary water level.

• Publications of The Korean Astronomical Society
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• v.26 no.3
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• pp.89-101
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• 2011

The International Olympiad on Astronomy and Astrophysics (IOAA) initiated by the Thailand Astronomical Society in 2007 is an annual competition for high school students. One of its aim is to enhance the development of international exchange in the field of school education in astronomy and astrophysics. This paper first provides the overview of the IOAA in terms of key regulations based on its statutes, history and current status. Secondly, the published syllabus of the IOAA is used for content analysis according to subject areas regarding the exam questions of the IOAA in theoretical, observational and data analysis parts from 2007 to 2010. Also, a scientific inquiry framework is applied to the same questions for assessment based on scientific inquiry in the cognitive aspect with two sub-classes of scientific knowledge and scientific reasoning. Among a dozen astronomy subject areas listed on the syllabus, the theoretical part of the IOAA makes more frequent use of the Sun, the solar system, properties of stars, and concept of time. In content knowledge, a factor of scientific knowledge, the IOAA questions, especially in the theoretical part have a lesser degree in difficulty than the IAO (International Astronomy Olympiad) exam questions for the same period whose degree in difficulty is comparable to college level. With regard to scientific reasoning, the IOAA questions tend to involve convergent rather than divergent thinking. Lastly, in light of these findings, discussions are given on the outcome of Korean participation in the previous IOAAs and ways to help better in preparing Korean students for future astronomy Olympiads.

• The Journal of the Convergence on Culture Technology
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• v.6 no.3
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• pp.437-442
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• 2020

Since the advent of the innovative information technology called the Internet, the dynamism of the information environment has brought about changes in information users' needs and behavior. It is essential to understand information users in this rapidly changing environment, and based on this, it is necessary to effectively build and operate an information service and a system therefor. The purpose of this study is to understand the characteristics according to the segmentation of users of the National Science and Technology Information Service System, and to derive improvements to customized services and content development through research and analysis of content usage. A total of 816 science and technology information service system users participated in online surveys from September to November. Collected data is applied to factor analysis and cluster analysis techniques to subdivide users of science and technology information service systems, to recognize new information technologies and information services, science technology information needs, and science and technology attributes that users consider important. We derived the results according to the segmented user group.

• Journal of Korean Academy of Nursing
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• v.37 no.3
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• pp.313-323
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• 2007

Purpose: Health-related quality of life (HRQOL) in patients with cardiovascular disease in Korea has rarely been studied, mostly due to the lack of a psychometrically validated disease-specific instrument. The purpose of this study was to develop and validate a cardiovascular specific-HRQOL questionnaire (CD-QOL). Method: The CD-QOL was developed and validated as follows; item generation, pilot study, and psychometric tests. Patients were recruited from three-university hospitals. The patients were asked to complete the preliminary questionnaire comprising the content-validated items, SF-36, and CES-D. The NYHA and KASI classifications were used to classify the functional performance of the patients. The data was analyzed using correlation, factor analysis, multidimensional scaling, multitrait/multi-item matrix, ANOVA, and Cronbach's alpha. Result: Preliminarily, thirty-nine items were generated. Factor analysisextracted a five-factor solution with a total of twenty-two items. One item was deleted based upon the MDS. The remaining items were moderately correlated with the subscales of the SF-36 and associated with depression measured with the CES-D. The mean scores of patients in NYHA and KASI class I were significantly higher than those in NYHA and KASI class II or/and III, which suggested patients with better functional performance were likely to have a better HRQOL. Cronbach's alphas of the total and subscales were all greater than 0.70. Conclusion: The CD-QOL is a easily applicable instrument with excellent psychometric properties of content, criterion, factorial, convergent, and known-groups validity, and internal consistency reliability in Korean patients with cardiovascular disease.

• Journal of Korean Elementary Science Education
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• v.24 no.5
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• pp.531-538
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• 2005

The primary purpose of the study was to investigate the degree of difficulty and the causes of the difficulties in science instruction reported by elementary teachers and students. The secondary purpose was to suggest the effective methods to both of them to improve the efficiency of science instruction. For this study, the survey was carried out on 322 students and 156 teachers in the 3rd, 4th, and 5th grades. The questionnaires consisted of interest, difficulty and its factors. The results of this investigation are summarized as follows; 1. Teachers had relatively higher interest than students in science instruction content(textbook). Furthermore, the units that teachers showed interest differed from those that students had. This means that there is a significant difference of interest in instruction process between teachers and students. 2. Teachers felt much higher difficulty than students in the content of science instruction. This shows that the degree of interest might have little relation with that of difficulty, and that teaching of science seemed more difficult than teaming. Moreover, there was a difference of difficulty in the units between the teachers and students. The result shows a distinctive difference of difficulty in 8 units of the 3rd grade, 9 units n the 4th grade, and 12 units in the 5th grade (p<.05, p<.001, p<.005, respectively). It means that the difficulty depended on the units. 3. Students responded that they are responsible for difficulty factors of teaming, otherwise teachers thought that students are responsible for it, when the factors were divided into student factor, teacher factor, and curriculum factor. 4. Students demanded many experiments in the lab as well as easy and interesting instructions in order to reduce the degree of difficulty and to improve the condition of science instructions. However, teachers demanded the expansion of experimental equipments and materials as well as the improvement of the lab condition.

• Journal of Korean society of Dental Hygiene
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• v.21 no.2
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• pp.171-182
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• 2021

Objectives: Recently, subjective career success has been used as a criterion for evaluating career success. The purpose of this study was to develop and evaluate a simplified subjective career success inventory for dental hygienists. Methods: Subfactors of the subjective career success inventory consisted of career satisfaction, employability, and job satisfaction. The validity and reliability of the existing tools were evaluated through the basic items composition, content validity index (CVI), preliminary survey, and main survey process according to dental hygienists. The preliminary survey was composed of 35 questions by verifying the content validity twice from the existing 63 questions, and the main survey was conducted with a total of 12 questions. Samples were conveniently extracted from dental hygienists with a clinical career of ≥3 years and surveyed online from March 12, 2020 to June 30, 2020. Data of 320 people were collected, of which 284 were finally analyzed. The validity and reliability were analyzed using SPSS 18.0 and AMOS 18.0 (p<0.05). Results: The subjective career success was a shortened inventory composed of nine questions, and the overall reliability was Cronbach's α=0.841. Using exploratory factor analysis, three factors were extracted. As a result of the confirmatory factor analysis, each measurement variable significantly explained the latent factor, and the fit of the model was appropriate. The fit of the model was appropriate for the structural equation model. Among the sub-factors of subjective career success, career satisfaction and job satisfaction had a significant effect on intention to stay (p<0.05). Conclusions: The simplified subjective career success inventory developed for dental hygienists was found was found to be a useful tool in terms of reliability and validity.