• Journal of Biosystems Engineering
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• 제20권4호
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• pp.351-359
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• 1995

In pressure cooling system, produce were packed in vented box and cooled rapidly by producing a difference in air pressure on opposite faces of stacks of vented box. So, energy requirements and performance of pressure cooling system depended upon the air flow rate and the static pressure drop through packed produce in vented box. The static pressure drop across packed produce in vented box normally depended upon air flow rate, vent area of box and conditions of produce bed (depth, porosity, stacking patterns, size and shape of products) in box. The objectives of this study were to investigate the effect of vent area and air flow rate on airflow resistance of empty box and packed produce in vented box, and to investigate the relationship between the air flow resistance of packed products in vented box and sum of air flow resistance of empty box only and products in bulk only. Mandarins and tomatoes were used in the experiment. The airflow rate were in the range of 0.02~1.0$m^3$/s.$m^2$, the opening ratio of vent hole were in the range of 2.5~20% of the side area. The results were summerized as follows. 1. The pressure drops across vented box increased in proportion to superficial air velocity and decreased in proportion to opening ratio of vent hole. A regression equation to calculate airflow resistance of vented box was derived as a function of superficial air velocity and opening ratio of vent hole. 2. The pressure drops across packed produce in vented box increased in proportion to superficial air velocity and decreased in proportion to opening ratio of vent hole. 3. Because of the air velocity increase in the vicinity of vent hole in box, the airflow resistances of packed products in vented box were always higher than sum of air flow resistance of empty box only and products in bulk only. 4. Based on the airflow resistance of empty box and products in bulk, a regression equation to calculate airflow resistance of packed products in vented box was derived.

• 한국수학교육학회지시리즈C:초등수학교육
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• 제21권2호
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• pp.237-260
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• 2018

본 연구는 4개국의 초등학교 수학 교과서 비와 비율 단원에서 어떠한 모델을 사용하고 있는지 알아보고, 비례에 대한 곱셈적 사고와 비례 상황의 구조에 따라 이러한 모델이 교과서에 어떻게 반영되어 있는지 살펴보았다. 이를 위해 한국, 일본, 싱가포르, 미국의 초등학교 5, 6학년 수학 교과서를 비교 분석하였다. 그 결과 그림 모델과 비표, 이중수직선, 테이프 다이어그램에서 비례에 대한 곱셈적 사고와 비례 상황의 구조에 따른 차이를 확인할 수 있었다. 또한 다중묶음관점에서 변동부분관점으로 이어지는 일본교과서의 전개나 두 가지 이상의 모델이 함께 쓰인 각 나라 교과서의 사례에서 곱셈적 사고의 연결 및 통합 가능성을 찾을 수 있었다. 따라서 학생들의 곱셈적 사고를 신장시키고 측정 공간 내 또는 측정 공간 사이의 비례추론을 지도하기 위해 차기 교과서에서 어떤 종류의 모델을 어떻게 제시하는 것이 효과적일지 좀 더 신중한 검증과 논의가 필요하다.

• 한국식품조리과학회지
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• 제19권5호
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• pp.571-580
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• 2003

The purpose of this study was to assess the optimum coating ratio for rice, using various ratios of mulberry leaves extract, 1.0, 1.5, and 2.0%, and to determine the optimum ratio of added water, in proportion to the total weight of mulberry rice. The moisture content of the soaked rice, and the optimum water uptake rate, moisture content of the cooked rice, as well as its blue and color values, mechanical characteristics, internal structure and sensory evaluation, were analyzed. The statistical data analyses were completed using the SAS program. The results are summarized as follows: The moisture content of mulberry rice was less than that of raw rice. The average optimum water uptake of the soaked mulberry rice at the different water temperatures, 10, 20 and 30, was 20% of the total weight of the raw mulberry rice. As for the results of the sensory evaluation,; 140% water, in proportion to the total weight of raw mulberry rice, was judged to be the optimum. The average moisture content of the cooked mulberry rice was 45∼50%, but there was no significant difference in the various coating ratios. The blue value of the cooked mulberry rice awas highest on the first day of cooking. The L- and a-values decreased with increasing coating ratio, but the b-value increased under the same conditions. As for the mechanical characteristics,; the adhesiveness, hardness and springiness decreased during 2 days of storage. The internal structure of the mulberry rice, observed by SEM, showed a close structure on increasing the coating ratios of mulberry leaves extracts. It was concluded that the optimum coating ratio of mulberry rice and ratio of added water for cooking wereas 1.5 and 140%, respectively, in proportion to the total weight of raw mulberry rice.

• 한국조리학회지
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• 제4권
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• pp.225-248
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• 1998

The purpose of this study is to examine the change of the shape of sponge cake in proportion to the raw material mixture and the degree of dough. It is examined that the measures of the degree of dough in proportion to the material mixture, and the sense examination and measure of moisture with this sponge cake. The test results indicate that 50% sponge cake is most soft among the ratio of other material mixtures, and sponge cake is more soft as the degree of dough is lower. Therefore, the shape of sponge cake is greatly changed in proportion to the mixture of materials and the degree of dough.

• 대한가정학회지
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• 제26권4호
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• pp.113-127
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• 1988

This paper attempts to investigate and analyze the change of the proportion of discretionary consumption expenditure (DCE) of main consumer goods among total household expenditure from 1964 to 1986 in Korea by reorganizing various data, particularly "Annual Report of Citizen's Household Experditure in Sooul".The result of the author's analysis can be summarized as follows. 1. The analysis shows that while the proportion of DCE in food has been increased during this period as the Korean economy developed, the value of income elasticity for beverages, liguor, out-door eating and processed food products which consist of major part of food, has been successively decreased. And also, though the absolute value of income elasticity for grain products has been increased, its proportion among total expenditure has been successively decreased. From these trends, we can conclude that general consumption pattern has a tendency to change from dependence on main grain products to the more utilization of out-door eating or processed food products. 2. The ratio of DEC of furnitures to housing expenditure has played a role of indicator of business cycle, reflecting the consumers' psychological expectation fro general economic trend. 3. In case of the proportion of DCE of clothes, there has been no great change. 4. As for as DCE of sundry expenditure is concerned, there has been no-great change in The proportion itself/ However. as the ratio of sundry expenditure to total household expenditure has been greatly increased, expenditure for leisure disproportionately increased. 5. The proportion of total DCE in total consumption expenditure, as in the case of housing, has been increased, which coincided exactly with business cyele appeared during this period. In fact, when Korea economy experienced a severe recession in 193 and 1980, that proportion deeply went down respectively, and again went up after those years. Accordingly, we can generalize that the size of DCE deperds on the formation of consumer's psychological expectation toward economy, which confirms George Katona's early proposition.

• International Journal of Contents
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• 제6권3호
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• pp.71-82
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• 2010

The golden ratio is a mysterious number that surprisingly appears in science, physics, mathematics, as well as in nature. The number 1.618 seems to be a universal constant, and crops up whenever the subject is of beauty or elegance. Beautiful flowers and sea shells and also attractive people have a common number and that is 1.618 or $\varphi$ (phi). This paper does a study into the story of phi, and describes how the golden ratio is derived. Artists, architects and designers have employed the ratio into dimensioning their works of art to achieve visual appeal. Examples such as the Greek Parthenon of the Acropolis and paintings such as the Last Supper all use this magic number. An investigation was conducted among 50 people to test if looking at golden proportioning was actually appealing, or if it was just a type among overzealous enthusiasts. The results show that the golden ratio may actually be of some use.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.82-89
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• 2004

To secure stability and availability of Rammed Aggregate Pier method as the foundation of a structure, the shear strength characteristics according to the area replacement ratio of RAP and the relative density of in-situ ground was studied through soil laboratory tests and large direct shear tests in a model ground. As a result, the internal friction angle tends to increase in proportion to in-situ relative density(Very Loose, Loose, Medium) in composite ground formed by the same area replacement ratio of RAP and also increase in proportion to increasing the area replacement ratio(30, 40, 50%) of RAP in the same ground condition. Furthermore, the comparative analysis between the experimental value and theoretical value of the shear strength is carried out.

• 산업경영시스템학회지
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• 제18권33호
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• pp.39-43
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• 1995

The purpose of this article was to understand the individual proportion of quality costs which have been expended by manufacturing industries in Seoul and Kyunggido district. The collected data on 72 firms could be use for an empirical analysis and the ratio test was implementented with the questionnaires. The finding were as following : by conparison with the proportion of quality cost in typical manufacturing industrial of U.S., We concluded that total quality cost was occupied with a small portion of sale. Also as compared with the individual item of quality cost, it was noted that the proportion of prevention cost had increased in a relatively large company.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.73-78
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• 2002

This study examines self-compacting of concrete using Ground Calcium Carbonate(GCC) gathering in limestone mine of Banyans district in order to make self-compacting concrete in the range of design strength 300kgf/cm$^2$ and the optimal mix proportion of self-compacting concrete that can use in field structure. The result shows that the optimal GCC replacement ratio is 45$\pm$5% in the normal strength of design strength 300kgf/cm$^2$ and that the volume ratio of the optimal fine aggregate used as the way satisfying both viscosity and compacting ability without separating materials is 46%. The optimal volume ratio of the coarse aggregate considering the economical aspect of concrete is 50%. It is desirable that the optimal mix proportion satisfying self-compacting for replacement of GCC is decided through mix design according to each replacement ratio.

• 한국수학교육학회지시리즈D:수학교육연구
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• 제12권2호
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• pp.85-108
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• 2008

In this study, we created, implemented, and evaluated the impact of proportional reasoning authentic investigative activities on the mathematical content and pedagogical knowledge and attitudes of pre-service elementary and middle school mathematics teachers. For this purpose, a special teaching model was developed, implemented, and tested as part of the pre-service mathematics teacher training programs conducted in Israeli teacher colleges. The model was developed following pilot studies investigating the change in mathematical and pedagogical knowledge of pre- and in-service mathematics teachers, due to experience in authentic proportional reasoning activities. The conclusion of the study is that application of the model, through which the pre-service teachers gain experience and are exposed to authentic proportional reasoning activities with incorporation of theory (reading and analyzing relevant research reports) and practice, leads to a significant positive change in the pre-service teachers' mathematical content and pedagogical knowledge. In addition, improvement occurred in their attitudes and beliefs towards learning and teaching mathematics in general, and ratio and proportion in particular.