• Journal of the Korean Data and Information Science Society
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• v.14 no.4
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• pp.877-887
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• 2003

A two-stage procedure is proposed to estimate the population proportion of a sensitive group. The proposed procedure is obtained by combining the direct question method and a modified randomized response technique. It is verified that the proposed procedure is more efficient than existing methods under some mild conditions.

• Communications of Mathematical Education
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• v.24 no.2
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• pp.345-363
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• 2010

The purpose of this study is to investigate and analyze informal knowledge of students who do not learn the conception of proportion and to identify how the informal knowledge can be used for teaching the conception of proportion in order to present an effective method of teaching the conception. For doing this, proportion was classified into direct and inverse proportion, and 'What are the informal knowledge of students?' were researched. The subjects of this study were 117 sixth-graders who did not have prior learning on direct and inverse proportion. A total eleven problems including seven for direct proportion and four for inverse proportion, all of them related to daily life. The result are as follows; Even though students didn't learn about proportion, they solve the problems of proportion using informal knowledge such as multiplicative reasoning, proportion reasoning, single-unit strategy etc. This result implies mathematics education emphasizes student's informal knowledge for improving their mathematical ability.

• Journal of Educational Research in Mathematics
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• v.26 no.3
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• pp.403-420
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• 2016

Some of the critical changes in the revised 2015 Korean Mathematics curriculum were that direct proportion and inverse proportion were moved from elementary school to middle school and that supplementary content related to correlation was included. These decisions were based on comparative studies of international curriculum. Therefore in this study, we selected countries for comparison; United States, England, France, Finland, Australia, Japan, Singapore, China and Taiwan. We looked into the timing and scope for direct/inverse proportion and correlation in curricula of these countries. Along with this, we established four criteria; vertical sequence, horizontal sequence, external connection, and internal connection for an analysis framework. Then we compared and analysed the direct/inverse proportion and correlation in each curriculum. As a result, in most of these curricula, the direct/inverse proportions are introduced at middle school or are introduced at elementary school and then developed further at middle school. Most of curriculums on direct/inverse proportion and correlation match the four criteria. Correlation is introduced in high school mathematics in all counties except Finland and it is dealt in diverse context introducing related concepts, for example, correlation coefficient, regression straight line, and least square. We suggested that it is necessary to refer these international trends for the next revision of curriculum.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.137-148
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• 2015

So far, the phenomenon of "electrification" has been deepened in Korean industry and especially direct heating energy which accounted for 44.0%(2010) of total energy consumed in Korean manufacturing has been significantly electrified. This paper decomposed electricity consumption for direct heating in Korean manufacturing from 1992 to 2012 using LMDI(Log Mean Divisia Index). This paper includes 4 different factors such as electricity proportion effect, direct heating proportion effect, energy intensity effect and added value effect. And this paper compared the consumption pattern by business type. As results, electricity proportion effect had contributed the most to the increase of electricity consumption for direct heating in Korean manufacturing. And Petrol-Chemical and Iron & Steel had the most electrification of direct heating.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.2
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• pp.199-210
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• 1997

The purpose of this study was to investigate the mutual relationship between food preference and nutrient intake status of high school students, based on the their personal characters which are sex, age, family type, number of family, mother's age, occupation, and school career. 439 students were selected with random stratified cluster sampling method. The study used a self-administrated questionnaire and 24-hour recall method for 5 days as instrument tools. Statistical methods applied to analyze the data were frequency, percent, Willcoxon Rank-sum test, Kruskal-Wallis test, ${x^2}-test$ by contingence table, and Spearman's correlation coefficient in non parametric statistical methods. Some of interesting results are as follows : 1. The correlation between sex and the set of characters of mother's age, school career and income is highly significant. However there is no any significant difference on the kinds of job and the types of family. 2. The relation between the preference of main dishes and the nutrient intake show a significant difference except to the noodles. This marks that preference of main dishes shows a direct proportion with the nutrient intakes except for the fat, vitamin A, vitamin C. 3. The preference of animal food marks a direct proportion with the nutrients such as energy, protein, fat, fiber, phosphorus, iron, vitamin $B_{1}$, vitamin $B_{2}$, and niacin 4. The preference of vegetable food gives some influence on the nutrient intake but the preference of soup is insignificant, the preference of Kimchi is in reverse proportion, and the preference of vegetable marks a direct proportion with the nutrient intake. 5. The preference of snacks marks a direct proportion with all kinds of nutrients intake except for the vitamin A, and vitamin C.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.4
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• pp.129-137
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• 2019

Tax can be categorised into direct tax and indirect tax. This paper uses the ordinary least-squares regression method to study the impact of direct and indirect tax on economic growth in Vietnam in the period 2003-2017. Statistical data is collected from the Ministry of Finance of Vietnam. Theoretically, tax generates the state budget revenue and is a tool to regulate the economy. The results of statistical tests show that tax has a positive impact on Vietnam's economic growth. However, the effects of direct tax and indirect tax are different. The indirect tax has a positive influence and promote Vietnam's economic growth, while the impact of the direct tax is invisible. There has not been sufficient evidence to confirm that the indirect tax has a more positive impact than the direct tax. To promote economic growth, Vietnam needs to restructure its tax system towards: (1) Increasing the proportion of indirect tax, reducing the proportion of direct tax in the state budget revenue; (2) Expanding tax bases; (3) Reducing tax rates of corporate income tax and personal income tax; (4) Increasing tax rates of environmental protection tax, natural resources tax, value added tax and excise tax on some types of goods which harm health and environment.

• Journal of the Korean Data and Information Science Society
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• v.14 no.2
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• pp.275-278
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• 2003

In this paper, a simple and obvious procedure is presented that allows to estimate $\pi$, the population proportion of a sensitive group. Suggested procedure is combined procedure of direct question and randomized response technique. It is found that the proposed procedure is more efficient than Warner's(1965).

• Korean Journal of Human Ecology
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• v.12 no.5
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• pp.713-735
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• 2003

The purpose of this study was to investigate the effects of the characteristics of maternal social networks on maternal expectation for their own children to examine the path that social networks had an effect on the self-esteem and the emotional intelligence of children through maternal expectation for their own children. The data used in this study were collected from 524 fourth to sixth graders and their mothers residing in Daejeon using structured questionnaire. The major findings of the study were as follows : (1) Among social network characteristics, proportion of friends and neighbors, proximity, direction and interference had a negative effect, and proportion of mothers of child's friends, frequency of contact, intimacy, emotional support, service support had a positive effect on maternal expectation for their own children. (2) Among social network characteristics, proportion of mothers of child's friends had a direct effect and proportion of friends, neighbors, and mothers of child's friends, proximity, frequency of contact, intimacy, direction, emotional support, service support, and interference had an indirect effect on children's emotional intelligence through maternal expectation for their own children. (3) Among social network characteristics, proportion of kin and mothers of child's friends, intimacy, service support, material support and interference had a direct effect, and proportion of neighbors and mothers of child's friends, proximity, frequency of contact, direction, service support had an indirect effect on children's emotional intelligence through maternal expectation for their own children.

• The Mathematical Education
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• v.46 no.3
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• pp.315-329
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• 2007

The concepts of ratio, rate, and proportion are used in everyday life and are also applied to many disciplines such as mathematics and science. Proportional reasoning is known as one of the pivotal ideas in school mathematics because it links elementary ideas to deeper concepts of mathematics and science. However, previous research has shown that it is difficult for students to recognize the proportionality in contextualized situations. The purpose of this study is to understand how the mathematical concept in the middle school mathematics curriculum is connected with ratio, rate, and proportion and to investigate the characteristics of proportional reasoning through analyzing the concept including ratio, rate, and proportion on the middle school mathematics curriculum. This study also examines mathematical concepts (direct proportion, slope, and similarity) presented in a middle school textbook by exploring diverse interpretations among ratio, rate, and proportion and by comparing findings from literature on proportional reasoning. Our textbook analysis indicated that mechanical formal were emphasized in problems connected with ratio, rate, and proportion. Also, there were limited contextualizations of problems and tasks in the textbook so that it might not be enough to develop students' proportional reasoning.

• Journal of Families and Better Life
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• v.14 no.2
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• pp.127-138
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• 1996

The purpose of this study is to show farm women's stress under productive activity role multiple overload through family characteristic (pattern and number) and characteristic(type working time and involvement proportion) of productive activity. The outline of the study is as follow; 1. Stress by pattern and number of a family is highest in a four generation family and increases according as the number of the family increases. 2. The characteristic of productive activity : 1) Stress based on type of productive activity is highest in Type III of the most multiple overload roles. 2) in light of stress based working time area of household task activity is in inverse proportion to working time but area of farming and wage earning activity are approximately in direct proportion to it. The two-way ANOVA analysis show that stress in Type I of area of household task increases but in Type IV it decreases as working time increases 3) In stress based on involvement proportion to it. The wo-way ANOVA analysis show that stress in Type I of area of household task increases but in Type IV it decreases as working time increases. 3) In stress based on involvement proportion in three as working time increases 3). In stress based on involvement proportion in three activity areas the more the involvement proportion the less of the stress : an inverse ratio.