• School Mathematics
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• v.4 no.4
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• pp.633-642
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• 2002

This paper focuses on the concepts of a value of ratio and a rate in elementary school mathematics. Although the concept of a value of ratio can be distinguished meaningfully from that of a rate by phenomenological analyses, this distinction is impossible at the elementary school level. Two concepts tend to be treated as identical, therefore they need to be classified by the other methods. By analyzing the series of mathematics textbooks from the first curriculum to the present 7th curriculum, this paper investigated how two concepts have been transposed into the products of school mathematics. In addition, we discussed how the difference of two concepts in the changing process of definitions have been presented clearly to the students. As a result, this paper concluded that the difference of two concepts has not been developed clearly for elementary students in general, except the textbook by the 7th curriculum. The definitions of two concepts were described obscurely so that the students may confuse the concept of a value of ratio with that of a rate. The role of a value of ratio needs to be reconsidered when it is applied to set proportional expressions. Therefore, this paper suggests not adhering to the terminology ‘value of ratio’ to present the ratio as a quotient or the rate as a fractional representation in school mathematics.

• Journal of Korean Physical Therapy Science
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• v.28 no.3
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• pp.1-10
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• 2021

Background: The purpose of this study is to investigate the effect of the online team project based learning on problem-solving, cooperative self-efficacy, and cooperative self-regulation of college students. Design: Single group pre-post design. Methods: The online team project based learning was conducted for a total of 92 college students for 8 weeks. A survey was conducted on problem-solving ability, cooperative self-efficacy, and cooperative self-regulation. In the online team project-based class, two projects were performed. It consists of video lectures and real-time video conferencing. Through the real-time video conference, the project was carried out based on discussion among learners and feedback was provided. Results: There was a significant difference in the change in problem-solving ability compared to before learning (p<0.05). As a result of the evaluation of cooperative self-efficacy, there was a significant difference (p<0.05). There was a significant differences in cooperative self-regulation compared to before learning (p<0.05). Conclusion: The online team project-based learning are effective in improving learners' problem-solving ability, cooperative self-efficacy, and cooperative self-regulation.

• Korean Journal of Health Education and Promotion
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• v.24 no.2
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• pp.15-28
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• 2007

Objectives: In this paper, the survey on internet usage patterns of health consumers was conducted and analyzed in order to determine internet health information assessment criteria for providing correct consumer health information on web-sites. Methods: By using a survey questionnaire with 16 questions on general information and 20 questions on internet health information, data were collected from September 16 to 25, 2005 from 476 participants through an internet web site, http://www.hp.go.kr. Frequency analysis, t-test, and multiple regression were used in order to analyze the difference in assessment criteria, factors influencing assessment criteria, factors influencing user satisfaction, etc. Results: General characteristics of the study population were: the persons over age 40 were the smallest age group; women were accounted for 74.2%; and the persons with average income were the largest income group; and the persons with average health status were the largest health group. Most widely used health information were: exercise, disease, and diet, in order. There was significant difference(p=.001) in importance of assessment criteria between the persons in medical institutions and the persons not in medical institutions. There was no significant difference in other assessment criteria. We also found that contents of websites and easy to use were more important factors than elucidation of information providers and information sources including speciality of information in quality assessment criteria of internet health information. Discussion and Conclusion: Results of this paper were compared with the previous studies from the literatures. Contrary to the previous studies in the literature, there was significant difference in importance of assessment criteria between the persons in medical institutions and the persons not in medical institutions. In order to apply the study results to develop health contents for consumer, there is a need for further upgrade the proposed assessment criteria based on expert opinion.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.260-267
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• 2016

Background: This study analyzes the differences in the annual averaged atmospheric dispersion factor and ground deposition factor produced using two classification methods of atmospheric stability, which are based on a vertical temperature difference and the standard deviation of horizontal wind direction fluctuation. Materials and Methods: Daedeok and Wolsong nuclear sites were chosen for an assessment, and the meteorological data at 10 m were applied to the evaluation of atmospheric stability. The XOQDOQ software program was used to calculate atmospheric dispersion factors and ground deposition factors. The calculated distances were chosen at 400 m, 800 m, 1,200 m, 1,600 m, 2,400 m, and 3,200 m away from the radioactive material release points. Results and Discussion: All of the atmospheric dispersion factors generated using the atmospheric stability based on the vertical temperature difference were shown to be higher than those from the standard deviation of horizontal wind direction fluctuation. On the other hand, the ground deposition factors were shown to be same regardless of the classification method, as they were based on the graph obtained from empirical data presented in the Nuclear Regulatory Commission's Regulatory Guide 1.111, which is unrelated to the atmospheric stability for the ground level release. Conclusion: These results are based on the meteorological data collected over the course of one year at the specified sites; however, the classification method of atmospheric stability using the vertical temperature difference is expected to be more conservative.

• Journal of Intelligence and Information Systems
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• v.19 no.4
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• pp.97-121
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• 2013

With the growing importance of knowledge for sustainable competitive advantages and innovation in a volatile environment, many researches on knowledge sharing have been conducted. However, previous researches have mostly relied on the questionnaire survey which has inherent perceptive errors of respondents. The current research has drawn the relationship among primary participant behaviors towards the participation level in knowledge sharing, basically from online user behaviors on Wikipedia, a representative community for online knowledge collaboration. Without users' participation in knowledge sharing, knowledge collaboration for creating knowledge cannot be successful. By the way, the editing patterns of Wikipedia users are diverse, resulting in different revisiting periods for the same number of edits, and thus varying results of shared knowledge. Therefore, we illuminated the participation level of knowledge sharing from two different angles of number of edits and revisiting period. The behavioral dimensions affecting the level of participation in knowledge sharing includes the article talk for public discussion and user talk for private messaging, and community registration, which are observable on Wiki platform. Public discussion is being progressed on article talk pages arranged for exchanging ideas about each article topic. An article talk page is often divided into several sections which mainly address specific type of issues raised during the article development procedure. From the diverse opinions about the relatively trivial things such as what text, link, or images should be added or removed and how they should be restructured to the profound professional insights are shared, negotiated, and improved over the course of discussion. Wikipedia also provides personal user talk pages as a private messaging tool. On these pages, diverse personal messages such as casual greetings, stories about activities on Wikipedia, and ordinary affairs of life are exchanged. If anyone wants to communicate with another person, he or she visits the person's user talk page and leaves a message. Wikipedia articles are assessed according to seven quality grades, of which the featured article level is the highest. The dataset includes participants' behavioral data related with 2,978 articles, which have reached the featured article level, with editing histories of articles, their article talk histories, and user talk histories extracted from user talk pages for each article. The time period for analysis is from the initiation of articles until their promotion to the featured article level. The number of edits represents the total number of participation in the editing of an article, and the revisiting period is the time difference between the first and last edits. At first, the participation levels of each user category classified according to behavioral dimensions have been analyzed and compared. And then, robust regressions have been conducted on the relationships among independent variables reflecting the degree of behavioral characteristics and the dependent variable representing the participation level. Especially, through adopting a motivational theory adequate for online environment in setting up research hypotheses, this work suggests a theoretical framework for the participation level of online knowledge sharing. Consequently, this work reached the following practical behavioral results besides some theoretical implications. First, both public discussion and private messaging positively affect the participation level in knowledge sharing. Second, public discussion exerts greater influence than private messaging on the participation level. Third, a synergy effect of public discussion and private messaging on the number of edits was found, whereas a pretty weak negative interaction effect of them on the revisiting period was observed. Fourth, community registration has a significant impact on the revisiting period, whereas being insignificant on the number of edits. Fifth, when it comes to the relation generated from private messaging, the frequency or depth of relation is shown to be more critical than the scope of relation for the participation level.

• Journal of the Korean Home Economics Association
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• v.37 no.1
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• pp.1-13
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• 1999

The purpose of this study is to find how the mate selection and sex consciousness reflected in Samhuk Yusa. We set up the following two questions for aim of this study. First, how are the real aspects and specific characters of mate selection reflected in Samguk Yusa? Second, how are the real aspects and specific characters of sex consciousness reflected in Samguk Yusa? The results can be summarized as follows; 1. Mate selection reflected in Samguk Yusa discussed into two major domains, one is spouse conditions and the other is marriage form. Men and Women are married at teenages, but the greater part of case is unidentified, so in order to approach this we need to analyse other historical documents. In men and women, standard of appearance and personality is difference. Analyzed case about appearance is a few, also we need to analyse other historical materials. More valued personality is wisdom in men, and in women more valued personality is virtue, brightness, graceful and mild. Through in case of to overcome the cultural gabs, the society must be open in every area. The marriage form is diversity, examples, free marriage, a marriage of convenience type, etc. Especially in aspects remarriage of man and woman is free in every class. 2. Sex consciousness reflected in Samguk Yusa discussed into three major domains, first is discussion about sex, second is premarital sexual behavior, third is extramarital. Through the case of discussion about sex is opened so there is not existence double blinded in sexual norms. Also through the case of premarital sexual behavior and extramarital, fidelity ideology does not yet come into existence.

• Journal of Internet Computing and Services
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• v.10 no.5
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• pp.135-143
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• 2009

The purpose of this study is to examine the variables related to the students' e-learning participation that have an effect on learning achievement in e-learning environment of cyber universities. Based on the related research, the followings are derive. First, students' attendance and participation in discussion showed higher correlation with the learning achievement than other participation variables. However, the total studying time in online classes showed lower correlation with the learning achievement. Second, the variables that have an effect on the learning achievement were in the order of students' attendance, participation in discussion, access frequency to online classes, learning progress and number of data uploads. Third, by the learners' background, the difference among the variables that have an effect on learning achievement were found. Based on the results above, this study suggests considerations about participation variables to enhance the learning achievement in cyber universities.

• Journal of Radiation Protection and Research
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• v.43 no.4
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• pp.143-153
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• 2018

Background: The determination of the amount of radionuclides and internal dose for the worker who may have intake of radionuclides results in a variation due to uncertainty of measurement data and ingestion information. As a result of this, it is possible that for the same internal exposure scenario assessors could make considerably different estimation of internal dose. In order to reduce this difference, internal exposure scenarios for nuclear facilities were developed, and intercomparison were made to determine the harmonization of dose assessment results among the assessors. Materials and Methods: Seven cases on internal exposures incidents that have occurred or may occur were prepared by referring to the intercomparison excercise scenario that NRC and IAEA have carried out. Based on this, 16 nuclear facilities concerned with internal exposure in Korea were asked to evaluate the scenarios. Each result was statistically determined according to the harmonization discrimination criteria developed by IDEAS/IAEA. Results and Discussion: The results were evaluated as having no outliers in all 7 cases. However, the distribution of the results was spread by various causes. They can be divided into two wide categories. The first one is the distribution of the results according to the assumption of the intake factors and the evaluation factors. The second one is distribution due to misapplication of calculation method and factors related to internal exposure. Conclusion: In order to satisfy the harmonization criteria and accuracy of the internal exposure dose evaluation, it is necessary that exact guidelines should be set on low dose, and various intercomparison cases also be needed including high dose exposure as well as the specialized education. The aim of the blind test is to make harmonization evaluation, but it will also contribute to securing the expertise and high quality of dose evaluation data through the discussion among the participants.

• The Journal of the Korean life insurance medical association
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• v.30 no.2
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• pp.12-15
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• 2011

Background: The beneficial effects of implantable cardioverter defibrillators (ICDs) in primary and secondary prevention patients are well established. However, data on potential differences between both groups in mortality are scarce. The aim of this study was to assess extra risk differences between primary and secondary prevention ICD recipients. Methods: Comparative mortality figures were calculated from a source article using mortality analysis methods. Results: Mortality ratio (MR) of primary and secondary prevention ICD recipients were 393% and 373%. Excess death rates (EDR) of both groups were 42 and 38 per 1,000. Discussion: MR and EDR were higher in primary prevention group. But, there was no significant difference.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.8 no.4
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• pp.451-462
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• 1996

In this study, which focuses on ice storage, a fundamental study in cooling and solidification was performed, including the interesting phenomena of density inversion, supercooling and dendritic ice. A numerical study was performed for natural convection and ice formation considering existence of subcooling and dendritic ice were analyzed numerically by using finite difference method and boundary fixing method. In the mesh, the solid fraction was introduced with adding as a term to the energy conservation equation. A flow in the dendrite was modelled as a flow in a porous medium, and the momentum conservation equation was modified to incorporate resistance forces involved in flows through porous media. A numerical solution of the time dependencies of dendrite area and dense ice front was successfully obtained, and the numerical results were good agreement with experimental results. Based on this methodology, a discussion was made of phenomena and characteristics of cooling and freezing processes under various conditions.