• Journal of the Korean Society for Nondestructive Testing
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• v.34 no.2
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• pp.176-183
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• 2014

Acoustic emission testing (AET) of cylinders is advantageous in that it can be directly conducted on cylinders installed in a car, without needing to dissemble them on a real-time basis. Therefore, users prefer AET over other nondestructive testing methods. Owing to these advantages of AET, it has been approved by the Department of Transportation of the U.S. as a safety evaluation method for pressure containers or as an alternative to the hydroproof testing method. This paper presents a study of the quantitative evaluation criteria for a container having ultrasonic testing defects and also for Type 1 and Type 2 gas cylinders, which are defective seamless pressure containers provided by NK, a manufacturer of pressure containers. For the Type 1 cylinder, the process from crack growth to leak was observed in a repetitive fatigue test using a 113 L container according to ASTM E 1419-02. Further, for the Type 2 cylinder, integrity was evaluated using a 119 L sound container and a container damaged by hydraulic pressure, by the slow-fill method according to ASTM E 2191-02. Based on the AET results of the Type 1 and Type 2 cylinders, quantitative evaluation criteria were established for a defective and non-defective container.

• Journal of the Korean Institute of Gas
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• v.17 no.6
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• pp.58-66
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• 2013

Among the risks which can be faced with fire, combustion toxicity is a significant influence on the survival. Fire toxicity researches have been limited generally on the lethal aspects. In this study, HF gas which can be generated from fire, and also found in general industrial site was used for analysis. Blood analysis and biochemistry analysis performed to find internal demage of experimental animals which were used for measuring average activity stopping time from Animal test(KS F2271: Gas hazard test). In addition, Using the malondialdehyde analysis, indicators of oxidative damage, we had quantitative analysis to target lymphocyte for measuring the oxidative damage caused by toxic substances.

• Journal of The Korean Association For Science Education
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• v.17 no.3
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• pp.251-260
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• 1997

The instructional influences of cooperative learning strategies, which emphasize mutual interdependency of learners, group goal, and individual accountability, upon students' achievement, the attitude toward science instruction and the perception of learning environment were investigated. Before instruction, the prior knowledge test about atoms and molecules, the test of attitudes toward science instruction, and the perception questionnaire of learning environment were administered, and the grade in the previous mathematics course was obtained. These scores were used as covariates. Mid-term examination score was used as blocking variable. For instruction, three different strategies-traditional individual learning, small group learning, and cooperative learning-were used and teaching materials for the units of mole and stoichiometry were also prepared. After instruction, the researcher-made achievement test, the test of attitudes toward science instruction, and the perception questionnaire of learning environment were administered. The perception questionnaire of group activities was also administered to the two treatment groups. In the quantitative subtest, the scores of cooperative learning group and small group learning group were significantly higher than those of traditional individual learning group. However, the cooperative learning group's scores in the achievement test and the qualitative subtest were significantly higher than those of small group learning group and traditional individual learning group. The students in the cooperative learning group were found to have the most positive perception of learning environment but to have similar attitudes toward science instruction. No interaction between the treatment and the level of the previous achievement was found in any of the analyses. In the perception questionnaire of group activities, students in both small group learning group and cooperative learning group exhibited positive perception of group activities. However, students in the cooperative learning group tended to think that their activities were related with their group's success. Educational implications are discussed.

• 한국초등상담교육학회:학술대회논문집
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• 2004.01a
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• pp.271-294
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• 2004

The purpose of this study was to examine the effects of MMTIC group counseling program on self-esteem of elementary school students. The hypothesis was that the self-esteem test scores of experimental group would be significantly higher than those of control group. The subjects were the twenty 5th graders sampled from the 66 5th graders of D Elementary School in Boryeong City based on self-esteem test scores. The 10 subjects were randomly assigned experiment group and others were assigned control group. The self-esteem test by Mun, Yong Woo (2002) modified from the measurement of Kim, Heui Hwa (1989) was administrated as pre and post test. The experimental group has experienced MMTIC group counseling program. On the other hand, the control group has not been given any advice during the counseling periods. The counseling was once a week at two o'clock in the afternoon for ten weeks from the eleventh of May to sixteenth of July in 2003. Each counseling session lasted sixty to eighty minutes. The group counseling program, which has been used in this research, has been adapted to the level of elementary students with the consideration of MBTI and MMTIC Workshop in reference to a few theses related to MMTIC development program (Jung, Gyeong Yeon, 2001: Gang, Jae Jeong, 2002; Lee, Jae Mo 2002). The results were analysed by t-test. These statistics with a quantitative result has been supplemented with a qualitative analysis by a questionnaire and the descriptions of impression of subjects of experimental group. The results of this research was that the analyses of the questionnaire and a description of their impression have shown that the counseling has had an significantly impact on their understanding themselves and others. In particular, this program has been positively conducive to receptive relationships to others. In conclusion, the MMTIC group counseling program has helped elementary students I understand themselves and others, increase receptive competence, encourage their confidence, improve personal relationships and enhance their adaptation to their school life. It suggests that this program has a feasible effect on children's sense of self-esteem.

• Fire Science and Engineering
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• v.25 no.5
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• pp.1-7
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• 2011

In this study, standards and test methods for building materials of domestic and foreign countries were compared and analyzed to propose evaluation methods for the fire-retardant performance of HANOK components (Traditional house). IBC and NFPA codes recently have been adopted in the US, and the properties such as critical heat flux, fire spread index and smoke density are being used as an evaluation reference. In Europe, the unified Euroclass has been adopted and the surface flammability, prototype fire test or cone calorimeter test are conducted for the performance test. Japan has the similar system as Korea where the class is classified into 3 grades. We tried to study a quantitative evaluation method of fire retardant performance for the HANOK components based on the analysis results of the several countries' standards and test methods for building materials.

• Journal of the Korean School Mathematics Society
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• v.12 no.1
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• pp.71-97
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• 2009

The study was to develop the instruments including instructional materials and test items for enhancing spatial ability. A mixed methodology was chosen to achieve the purpose of the study. To find students' achievement, 5 units of instructional materials were developed through the qualitative method and test items were tested through the quantitative method with 152 of the 8th-graders. The strategies to develop the instructional materials were: firstly to focus on mathematics properties for developing spacial ability; secondly, to allow students to follow hierarchical procedure o[ mathematical properties from 2-d to 3-d; thirdly, to recognize what the manipulative can do and can not; and fourthly, to guide students tn develop the process oriented thought, not the result oriented thought. For the test, 25 items were analyzed to assess students' achievement using validity, difficulty, and discriminator.

• Fire Science and Engineering
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• v.25 no.4
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• pp.35-41
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• 2011

Casualties due to toxic smoke products have been reported as major fire damage. There are various tests in order to evaluate toxic smoke from a fire at home and abroad, and KS F 2271 as a test of the gas hazard of building finish materials has been conducted in Korea. The current test of the gas hazard exposes rodent, laboratory rat, to smoke gases to evaluate combustion gas toxicity by measuring acting time of that. this study performed a test of the gas hazard for combustible polymer material, Urethane and rubber flooring, and determined gases with the FT-IR. Quantitative results compared with standard value defined in BS6853 and toxicity index (R) was calculated. Using relative comparison with animal test and the toxicity index, We tried a variety of toxicity evaluation by correlation analysis of two tests.

• Fire Science and Engineering
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• v.30 no.1
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• pp.43-48
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• 2016

In this study, the experiment to confirm the risks of particulate material was carried out as a precedent study for developing the toxicity evaluation method of combustion products including the toxicity of particulate material. In the experiment, the test result of filtering and exposing particulate material among combustion products and that of exposing combustion products including particulate material were compared and analyzed by analyzing changes in average movement stop time according to the installation of Membrane filter between the stirring box and test box through the gas toxicity test of the same specimen to filter particulate material among combustion products. As the test result, in case of installing a filter, the average movement stop time of an experimental rat increased by up to 264% in case of lumber specimen and up to 179% in case of urethane specimen. Through such result, the necessity of identifying the toxicity of particulate material and carrying out quantitative toxicity test for particulate material was confirmed.

• Journal of Sasang Constitutional Medicine
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• v.22 no.4
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• pp.49-55
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• 2010

1. Objectives The purpose of this study is to assess the statistical methods used in the Journal of Sasang Constitutional Medicine and to identify the types of errors in the statistical analysis. 2. Methods We have reviewed quantitative articles published in the Journal of Sasang Constitutional Medicine from 2000 to 2009. Except for the case report, a total of 505 articles was reviewed by year. We focused on the methods of statistics in these articles. We have analysed the number of thesis used the statistical methods, the number of the statistical methods, the types of the statistical methods, and the errors of the statistical methods with the object of 202 thesis used the statistical method. 3. Results 1. Of the 370 articles, 202 used inferential statistics. 2. The most dominant was the thesis with one type of the statistical method forming 61.9% (125 thesis) of the total. 3. The ANOVA was the statistic of choice overall (40.1%), followed by the t-test (35.6%). 4. By examining the errors of the statistical methods, there were 49 thesis with errors among 81 thesis using ANOVA, 25 thesis among 72 thesis using t-test, and 18 over 62 thesis using chi-squared test. 4. Conclusions We have found various mistakes or misuses in the applications of statistical methodologies in the articles published in the Journal of Sasang Constitutional Medicine. It is necessary to present the cases of inappropriate statistical methods in order to improve the quality of academic researches. So long as Sasang constitutional medicine uses the statistical methods, researchers should fully examine and be aware of the statistical methods which they wish to use through other research articles, and statistic publications.

• 한국지구물리탐사학회:학술대회논문집
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• 2008.10a
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• pp.41-46
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• 2008

After choosing twenty sluice culverts located at national rivers by detailed appearance evaluation, hydraulic response test and acoustic televiewer in addition to surface geophysical explorations were carried out to investigate the cavities which exist at the boundary of sluice culvert and ground. Tapping, GPR, 3-D resistivity surveys and acoustic televiewer imagery obtained successful results in limited conditions according to characteristics of the sites. On the other hand, hydraulic response test successfully detected cavity existing at the lower part of sluice culvert and its continuity. However, hydraulic response test can not supply the quantitative informations on the scale and the shape of cavity. Thus it is very important for accurate investigation to make comprehensive interpretation after supplying various surveys proper to site characteristics.