• Journal of the Korean Society for Nondestructive Testing
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• v.19 no.2
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• pp.100-109
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• 1999

A method is proposed to characterize single-fiber composite interphases from the frequency-domain characteristics of scattered ultrasonic waves, and its feasibility is investigated theoretically. It has been shown that the locations and magnitudes of the peaks and valleys in the frequency domain are affected significantly by the interphase properties, which may indicate the effectiveness of the proposed method. Although the frequency-domain behavior is basically associated with the resonance of the fiber-interphase system, it is not dominantly affected by the scatterer's resonance unlike that in the case of acoustic wave scattering. Therefore, the conventional acoustic resonant scattering theory is not directly applicable to the characterization of composite interphases. In order to solve the inverse problem of predicting the interphase properties from the frequency-domain characteristics of the ultrasonic scattered waves, an artificial neural network has been constructed. This approach has demonstrated reasonable accuracy in most cases considered in this study.

• Journal of The Korean Association of Information Education
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• v.22 no.1
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• pp.53-60
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• 2018

In this study we have developed a Python education program that can be applied to students who have studied block-based coding. We have developed a Python education program based on the extracted the learners' level of block-based coding by analyzing the programs and the textbooks. We extracted the grammar of the block-based coding and constructed the curriculum. Then, the Python education program was composed by 16 hours. After reviewing the appropriateness of the education program through expert validation, it was concluded that the developed Python education program is suitable for applying to learners of block-based coding. We expect that proposed program will be effectively applied as basic resources to learn script coding in class.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.4
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• pp.364-371
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• 2008

Ultrasonic waveguide sensor has been developed for under-sodium viewing of reactor internal structures of a sodium-cooled fast reactor (SFR). The structure design concept of a waveguide sensor assembly was suggested and evaluated for the application in SFR. A 10 m long ultrasonic waveguide sensor assembly has been manufactured and the experimental feasibility tests were carried out. The 10 m long distance propagation performance of zero-order antisymmetric $A_0$ Lamb wave has been verified. The feasibility of ultrasonic waveguide sensor has been demonstrated by the C-scanning resolution performance test.

• Korean Journal of Social Welfare
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• v.60 no.2
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• pp.5-28
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• 2008

This study tried to develop an test tool of social workers' ethical sensitivity(SWEST) on base of realization about the importance of ethical sensitivity of social worker who are required more ethicalities than the other professionals. Nevertheless, there has been no tool that can measure ethical sensitivity of social workers in our country up to now. Through analysis of existing ethical sensitivity tests in other professions, a paper and pencil method about unstructured question with cases including ethical issues and structured scoring system was chosen as an appropriate method for the SWEST. This study progressed in order : 1st collecting cases, 2nd composing cases, 3rd consulting cases, 4th pilot study, 5th making scoring standards, 6th determining case examples and scoring standards. With the result, the tool consists of 3 case examples with ethical issues : 1) self-determination and confidentiality, 2) equality and double relationship, 3) informed consent and conflict interest. And ethical sensitivities of social work major students and social workers were measured with the SWEST, to see practical utility of this test. The agreement degrees between two independent raters were above 90%. And respondent's ethical sensitivity displayed the most definite difference according to taking or not taking a course 'Social work values and ethics'. Through these results, it can be drawn that the SWEST is reliable and valid to test relevant differences in Korean social workers' ethical sensitivity. The SWEST is expected to activate studying, educating, and practicing ethics in social work.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.5
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• pp.436-442
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• 2008

Graphite material has been recognized as a very competitive candidate for reflector, moderator, and structural material for very high temperature reactor (VHTR). Since VHTR is operated up to $900-950^{\circ}C$, small amount of impurity may accelerate the oxidation and degradation of carbon graphite, which results in increased porosity and lowered fracture toughness. In this study, ultrasonic wave propagation properties were investigated for both as-received and degradated material, and the feasibility of ultrasonic testing (UT) was estimated based on the result of ultrasonic property measurements. The ultrasonic properties of carbon graphite were half, more than 5 times, and 1/3 for velocity, attenuation, and signal-to-noise (S/N) ratio respectively. Degradation reduces the ultrasonic velocity slightly by 100 m/s, however the attenuation is about 2 times of as-receive state. The results of probability of detection (POD) estimation based on S/N ratio for side-drilled-hole (SDHs) of which depths were less than 100 mm were merely affected by oxidation and degradation. This result suggests that UT would be reliable method for nondestructive testing of carbon graphite material of which thickness is not over 100 mm. In accordance with the result produced by commercial automated ultrasonic testing (AUT) system, human error of ultrasonic testing is barely expected for the material of which thickness is not over 80 mm.

• Journal of the korean academy of Pediatric Dentistry
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• v.45 no.2
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• pp.162-169
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• 2018

The purpose of this study was to compare the validity of $Cariview^{(R)}$, a new colorimetric caries activity test, with $CRT^{(R)}$ bacteria, a conventional bacterial culture method. In addition, this study assesses the correlation between the dental caries experience and activity between mothers and their children. 34 pairs of mothers and their children under the age of 6 years participated in this study with informed consent. After filling out a questionnaire and oral examination, the two caries activity tests above were performed on each subject. In the results, $Cariview^{(R)}$ scores were statistically significant with children's caries experience (r = 0.598, p < 0.01) and showed higher correlation than $CRT^{(R)}$ bacteria scores. $Cariview^{(R)}$ scores showed statistically significant correlation with the number of decayed teeth in both mothers and children (p < 0.05). In both $Cariview^{(R)}$ and $CRT^{(R)}$ bacteria tests, there was no statistically significant correlation between caries experience and caries activity (p > 0.05). $Cariview^{(R)}$ colorimetric test will be clinically useful for predicting future caries risk and establishing a preventative strategy in pediatric dentistry.

• Journal of Korean Home Economics Education Association
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• v.24 no.3
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• pp.1-34
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• 2012

The objectives of this study are to introduce a critical perspective of the multicultural education in home economics education, to develop teaching-learning materials and to apply them in classes for the purpose of enhancing students' multicultural competence for a validity test. For these purposes, family life culture sections from six high school technology and home economics textbooks were analyzed based on the contents and elements of multicultural competence. After recomposing the family life culture sections, this study developed 12-session teaching-learning materials with an emphasis on media literacy. Among them, 4-session plans were taught in classrooms for 247 students in the 10th grades. To test the validity of the plans, a questionnaires was given to the students as a pre- and post-test. The data were analyzed with paired t-tests. The results showed significant pre and post differences in all sections of multicultural competence except the section of 'general cultural understanding'. This implied that the developed teaching-learning materials were effective in helping students overcome ethnocentrism and enhance the understanding of cultural differences.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.5
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• pp.316-324
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• 2016

The purpose of this study is to review existing research trends to find highly reliable tools for measuring inconsistencies in parenting attitudes for adolescent children. We reveal factors that heavily affect reliability and feasibility of these tools and compose stable measurement items. We found a total of 37 items with high reliability and feasibility comprising six questions on affection, three questions on childcare, nine questions on interest, seven questions on demands, five questions on neglect, and seven questions on abuse. We surveyed first to third-year high school students in public and private schools nationwide and carried out statistical analysis for the 1,020 respondents. Upon analysis, questions were removed if they showed low factor loading (less than 0.6) for the father and mother in each of the 37 measurement items. Only questions that could be used for both the father and mother were extracted to carry out exploratory factor analysis. Eight questions were were deleted: five on interest, one on demands, one on neglect, and one on abuse. The final 29 questions were selected for the measurement tool. Cronbach's Alpha coefficient was used to analyze reliability, which showed high reliability values ranging from .857 to .931 for the father and mother. Therefore, these inspection tools for inconsistent parenting attitude were both reliable and feasible.

• Korean Journal of Child Studies
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• v.29 no.5
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• pp.13-30
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• 2008

This study aimed to examine the reliability and validity of a diagnostic instrument to be used to measure the developmental level of very young children (aged birth through 36 months) and to screen young children at risk. The subjects of this study were 861 young children. Data were analyzed by item response distribution, item discrimination, reliability, and validity of the scale. Items reflected the developmental level of each age group. Overall internal consistency was relatively high (Cronbach's ${\alpha}=.90{\sim}.95$), and test-retest (after 2 weeks) reliability was high. Content validity was examined by a panel of experts in the related field. The construct validity as well as the concurrent validity of this instrument was also established.

• The Journal of Korean Medicine
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• v.29 no.1
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• pp.7-14
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• 2008

Purpose : The purpose of study was to develop generalized validity evaluation methods and terms for Sasang type diagnostic tests. Methods : A generalized statistical evaluation model for Sasang typology was suggested and generalized validity evaluation indices were proposed with this model. Results : The usefulness of validity evaluations, such as sensitivity and specificity values, were confirmed by the systematic review of the data from previously reported studies. Conclusion :Major obstacles in the multi-facet analysis and systematic review for Sasang type diagnostic tests were discussed with this test validity study.