• Aerospace Engineering and Technology
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• v.8 no.2
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• pp.83-91
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• 2009

This paper concerns the dynamic property of TVC system in the upper stage of KSLV-I. The minimum bandwidth of TVC system is predicted by gathering and comparing the dynamic test data through whole development phases of KSLV-I. The linear models which approximate the dynamic data are also suggested. It is shown that the minimum bandwidth of KSLV-I TVC system is guaranteed over 6.0 Hz at one degree command. It is also shown that the linear model of KSLV-I TVC dynamics takes the form of the transfer function with an 8-th order denominator and a 2-nd order numerator. These results will play an important role in analyzing the flight stability and performance of KSLV-I.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.1
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• pp.19-25
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• 2018

Objective: In practical breeding, selection is often performed by ignoring the accuracy of evaluations and applying economic weights directly to the selection index coefficients of genetically standardized traits. The denominator of the standardized component trait of estimated genetic evaluations in practical selection varies with its reliability. Whereas theoretical methods for calculating the selection index coefficients of genetically standardized traits account for this variation, practical selection ignores reliability and assumes that it is equal to unity for each trait. The purpose of this study was to clarify the effects of ignoring the accuracy of the standardized component trait in selection criteria on selection responses and economic weights in retrospect. Methods: Theoretical methods were presented accounting for reliability of estimated genetic evaluations for the selection index composed of genetically standardized traits. Results: Selection responses and economic weights in retrospect resulting from practical selection were greater than those resulting from theoretical selection accounting for reliability when the accuracy of the estimated breeding value (EBV) or genomically enhanced breeding value (GEBV) was lower than those of the other traits in the index, but the opposite occurred when the accuracy of the EBV or GEBV was greater than those of the other traits. This trend was more conspicuous for traits with low economic weights than for those with high weights. Conclusion: Failure of the practical index to account for reliability yielded economic weights in retrospect that differed from those obtained with the theoretical index. Our results indicated that practical indices that ignore reliability delay genetic improvement. Therefore, selection practices need to account for reliability, especially when the reliabilities of the traits included in the index vary widely.

• Journal of Elementary Mathematics Education in Korea
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• v.19 no.1
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• pp.17-37
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• 2015

In this paper, we compared and analyzed the Korean National Mathematics textbooks of the 2007 amendment curriculum and the Harcourt Math in America focused on fractions and decimals. To summarize the results of the analysis are as follows. First, both textbooks introduce fractions to the meaning of parts-whole concept, but the Harcourt Math is stronger than that of Korean Mathematics textbooks in the concept of unit fractions as a generator of fractions. Second, the fractions can be considered trivial materials - a fraction representing 1 whole, a fraction with it's denominator is 1 - were more clearly represented in our US textbooks than those of our Korean textbooks. Third, in the introduction of the term relating to the fractions, Korea is a strong point of view of the classification of fractions than the point of view of representation in comparison with the case of the United States. Fourth, the equivalent fraction and equivalent decimal concepts were described more detail in the United States of textbooks than those of the case of Korean textbooks. Finally, the approaches of fraction and decimal concepts were introduced more mathematically in the case of the United States than those of the case of Korean textbooks.

• Journal of Preventive Medicine and Public Health
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• v.38 no.4
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• pp.443-448
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• 2005

Objectives : This study was done to evaluate the reliability of education and occupational class between using the health survey and the death certificate data. Methods : The 1998 National Health and Nutrition Examination Survey (NHANES) was conducted on a cross-sectional probability sample of South Korean households, and it contained unique 13-digit personal identification numbers that were linked to the data on mortality from the Korean National Statistical Office. The data from 263 deaths were used to estimate the agreement rates and the Kappa indices of the education and occupational class between using the NHANES data and the death certificate data. Results : The simple and weighted Kappa indices for education were 0.60 (95% CI=0.53-0.68) and 0.73 (95% CI=0.67-0.79) respectively, if the educational level was grouped into five categories: no-formal-education, elementary-school, middle-school, high-school and college or over. The overall agreement rate was 71.9% for these educational groups. The magnitude of reliability, as measured by the overall agreement rates and Kappa indices, tended to increase with a decrease in the educational class. The number of non-educated people with using the death certificate data was smaller than that with using the NHANES data. For the occupational class (manual workers, non-manual workers and others), the Kappa index was 0.40 (95% CI=0.30-0.51), which was relatively lower than that for the educational class. Compared with the NHANES, the number of non-manual workers for the deceased who were aged 30-64 tended to be increased (8 to 12) when using the death certificate data, whereas the number of manual workers tended to be decreased (59 to 41). Conclusions : The socioeconomic inequalities in the mortality rates that were based on the previous unlinked studies in South Korea were not due to a numerator/denominator bias. The mortality rates for the manual workers and the no-education groups might have been underestimated.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.29 no.6
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• pp.659-666
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• 2011

The absence of present accurate geospatial information can cause us to undergo severe problems in controlling the complicate and multiplicate disaster. Our country is trying to build the Disaster Spatial Data Infrastructure (DSDI), and the key information is the national framework data. This study aims to investigate the characteristics of disaster spatial data, and analyze the present conditions and problems of national framework data, and suggest the way to improve for the GIS application system. In order to provide a wide range of services through the national geospatial data integration system, the data management authority should be established to maintain the consistency of quality and data accuracy of the entire national spatial data infrastructure. In addition, the step-by-step update plan of the national geospatial data should be determined by means of the framework data. And the basic data (lowest common denominator) should be formulated to maintain the data consistency of national spatial information infrastructure.

• Health Policy and Management
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• v.18 no.3
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• pp.110-127
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• 2008

Expenditures on pharmaceuticals of different concepts were estimated and their functional, financing and providers' breakdowns were examined in line with the OECD's System of Health Accounts (SHA) manual. This study also shows the way such estimates are made. The results are then analyzed particularly from the international perspective. Data from both Household Survey by the National Statistical Office and the National Health and Nutritional Survey by the Ministry of Health and Welfare of Korea were used to estimate pharmaceutical expenditures that. are financed by out-of-pocket payments of the household, while national health insurance data etc. were used for estimation of pharmaceutical expenditures that are financed by public funding sources. The 'per capita expenditure on pharmaceutical/medical non-durables' in Korea stood at 380 US$ PPPs, less than the OECD average of 443 US$ PPPs in 2006, but its share of the per capita health expenditure of 25.9% noticeably outnumbered the OECD average of 17.1%, due partly to low per capita health expenditure as a denominator of the ratio. This indicates that Koreans tend to spend less on health care than an OECD average, while tending to spend more on pharmaceuticals than on other health care services, much like the pattern found in relatively low income countries. An international pharmaceuticals pricing mechanism is most likely responsible for such a tendency. In addition, it is to be noted that the percentage comes down to 21.0%, when expenditures on both medical non-durables and herbal medicine, which is locally quite popular among the elderly, have been excluded.

• Journal of Elementary Mathematics Education in Korea
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• v.14 no.3
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• pp.807-825
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• 2010

Educational interest has been paid to ADHD students. Because of being easily distracted, lacking concentration, and committing hyperactive acts, they lag much behind other students in academic grades and their teachers have many difficulties in teaching them. This study aims to provide a case of enhancing an ADHD student's fraction-related achievement. To do this, we investigated his mathematical abilities in a preliminary study, devised an individualized teaching for the fractions unit, and applied them to him. And analyzing the results from observations and interviews of the student we can induce the following results: First, the ADHD student showed such types of errors in relation to fraction as lack of the concept of dividing into equal parts, lack of the concept of numerator and denominator, and errors in adding or subtracting fractions anc mixed fractions whose denominators were the same. And secondly, the fraction-related achievements of the ADHD student have improved thanks to the systematic teaching plan based on the accurate understanding of his academic gap relative to other students, his learning attitude, and his time difference. In addition, this study suggests several implications for ADHD students' learning of fractions.

• School Mathematics
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• v.11 no.4
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• pp.643-664
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• 2009

This study was aimed to understand the problems that students experience during the self--directed study of a mathematics digital textbook and to find the implications for the design of digital textbook. For this study, we analyzed the process of self-directed learning on 'division of fractions with same denominator' using digital textbook by eight 6th graders. Students asked to use think aloud method while they study the unit. Their learning process was videotaped and analyzed by researchers after the experiment. After the self-directed learning, students filled out a test items and participated interview with a researcher. The result showed that students experienced several misconceptions and errors while using a digital textbook. The types of misconceptions and errors were cataegorized as "misconceptions and errors caused by a mathematics textbook" and "misconceptions and errors caused by a digital textbook". Especially, students showed several important misconceptions and errors because of the design factors. This implies we need to consider the causes of misconceptions for the design of a digital textbook.

• The Journal of Korean Academic Society of Nursing Education
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• v.8 no.1
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• pp.108-119
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• 2002

This paper as the basic study aiming the establishment of nursing theory according to Korean culture, is made to reveal the types of recognition about concepts of health immanent in Korean who have the health view, completely mixed with traditional oriental medicine and Confucianism and Buddhism and Shamanism and european scientific medicine, etc. This paper is using the Q-method, which is greatly effective in measuring the individual subjectivity, to collect rightly the concepts of health of objects. This analysis shows us the 4 types of recognition about concepts of health immanent in Korean as follows. Type Ⅰ: modern self-searching type(現代的 自己 追求型), Type Ⅱ: nature-sharing type(自然 共有型), Type Ⅲ: meaning-intentional altruism(意味 指向的 他者 中心型), Type Ⅳ: oriental adaptational type(東洋的 順應型). The men belonging to type Ⅰ have positive and self-searching view of health. They are not only interpreting the concept of health scientifically, but also positively accepting the oriental concept of health. The men belonging to type Ⅱ have strong tendency of down-to-earth. They not only have the naturalistic view of health as Taoist, but also carry the weight in the family and neighbour and regard co-sharing as excellent virtue. The men belonging to type Ⅲ are positive altruists, pursuing the meaning of life and at the same time setting the importance to the good value system. Naturally they care more the family and neighbour than themselves. The men belonging to type Ⅳ have oriental view of the world characterized by nature-adaptation. They positively agree to the Shamanism, Buddhism, Confucianism and Oriental concept of health. In conclusion, in all types we can see that Korean understand the harmony of man and nature as fundamental principle of heath and carry the more importance to the mind(心) than body(身) and at the same time esteem more the family-centric, oriental and organic community than individual. All above facts is immersed in the concepts of health of Korean as a common denominator.

• Journal of the Korean Data and Information Science Society
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• v.26 no.2
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• pp.367-376
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• 2015

Today, big data has become a hot keyword in that big data may be defined as collection of data sets so huge and complex that it becomes difficult to process by traditional methods. Clustering method is to identify the information in a big database by assigning a set of objects into the clusters so that the objects in the same cluster are more similar to each other clusters. The similarity measures being used in the cluster analysis may be classified into various types depending on the nature of the data. In this paper, we computed upper and lower limits for probability interestingness measure based similarity measures without marginal probability such as Yule I and II, Michael, Digby, Baulieu, and Dispersion measure. And we compared these measures by real data and simulated experiment. By Warrens (2008), Coefficients with the same quantities in the numerator and denominator, that are bounded, and are close to each other in the ordering, are likely to be more similar. Thus, results on bounds provide means of classifying various measures. Also, knowing which coefficients are similar provides insight into the stability of a given algorithm.