• Journal of Educational Research in Mathematics
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• v.25 no.3
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• pp.431-448
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• 2015

This study is conducted to understand the real shape of confusion surrounding mathematical terminologies, 'ratio' and 'rate' in both the US and Korea and to get some implications for Korean education. For this, various materials including textbooks and materials for kids and teachers, dictionaries, educational internet web sites, the past Korean elementary mathematics curriculums and etc are reviewed with respect to the terminologies related to 'ratio' and 'rate'. As a result, the findings are as follows. Firstly, the US and Korea have different views with ratio and rate. Secondly, Korean terminologies related to ratio and rate are not enough to treat the essentials of the concept of ratio and rate.

• Korean Journal of Agricultural Science
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• v.12 no.2
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• pp.292-308
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• 1985

This study was performed to obtain the basic data which can be applied to the use of foamed mortars using foaming agent of prefoamed type. The data was based on the properties of foamed mortars depending upon various mixing ratios of cement to fine aggregates, flow values and foam-cement ratio to compare those of cement mortar. The results obtained were summarized as follow; 1. At the mixing ratio of 1:0 and the foam-cement ratio of 6.00%, the increasing rate of water-cement ratio was 25% by flow $200{\pm}5mm$, 28% by flow $240{\pm}5mm$ and 32% by flow $280{\pm}5mm$. But it decreased as the mixing ratio gets poorer. The result showed that water amount increased because of the high viscosity caused by the increase of foam-cement ratio. The decrease of water-cement ratio was the greatest when the foam-cement ratio was 1.50%. 2. Absolute aridity bulk density of foamed mortars decreased with the increase of foam-cement ratio and the decrease of flow values. 3. Generally, compressive, tensile and bending strenghs of foamed mortars decreased with the decrease of flow values and the increase of foam-cement ratio. 4. The compressive strength was in proportion to tensile strength. It was estimated that the compressive strength was 8.8 times of tensile strength. The compressive strength was in proportion to bending strength. It was estimated that the compressive strength was 4.0 times of bending strength. The bending strength was in proportion to tensile strength. It was estimated that the bending strength was 2.1 times of tensile strength. 5. At the mixing ratio of 1:1 the lowest absorption rates were showed by foamed mortars, respectively. It was significantly higher at the early stage of immersed water.

• Korean Journal of Weed Science
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• v.11 no.3
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• pp.195-204
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• 1991

This study was conducted to determine physiological responses rice cultivars to glufosinate-ammonium. Changes of total protein content, protein population, glutamine synthetase activity, accumulated ammonia content and free amino acid composition were examined in both tolerant and susceptible rice cultivars. Tamjinbyeo and Fukei 126 showed relatively tolerant response to glufosinate-ammonium while Namyeongbyeo, Palgongbyeo and Youngdugbyeo were susceptible to it. Total protein content of two tolerant cultivars was 93.2 of the untreated control in average but three susceptible cultivars showed 76.5 of the untreated control in average, showing 16.7 difference. Protein profiles of the tolerant cultivars seemed to be not affected by glufosinate-ammonium treatment. However, in susceptible cultivar like Namyeongbyeo, 10ppm of glufosinate-ammonium application resulted in decrease of band density or disapperance of spot density in near 20kD and in between 45kD and 66kD on 2D-PAGE. Glutamine synthetase activity in susceptible cultivars was markedly inhibited by glufosinate-ammonium treatment, accompanying remarkable increase of ammonia content by three times greater than tolerant cultivars, and markedly increase of glutamic acid, showing 430% of the untreated control.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.373-383
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• 1987

No-fines concrete is concrete from which the fine aggregate fraction has been omitted. The concrete so formed, consisting only of coarse aggregate, cement, and water, has large voids uniformly distributed through its mass. This study was performed to obtain the basic data which can be applied to the use of no-fines concrete. The data was based on the properties of no-fines concrete depending upon various mixing ratios. The results obtained were summarized as follows. 1. Test result of the consistency, suitable water-cement ratio was increased with the increasing of mixing ratio. 2. At the suitable water-cement ratio, the highest strengths were showed. But it gradually was decreased with the increasing of mixing ratio and strengths are considerably lower than that of conventional portland cement concrete. 3. The relations between compressive and tensile strength were highly singnificant as a straight line shaped. The strength ratio was decreased with the increasing of mixing ratio and considerably lower than of conventional portland cement concrete. 4. Bulk density was decreased with the increasing of the mixing ratio, and was similar to that of the conventional portland cement concrete at mixing ratio 1:4. 5. The relations between strength and bulk density were highly significant as a straight line shaped. The decreasing ratio of strengths was higher than that of bulk density.

• Korean Journal of Agricultural Science
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• v.11 no.1
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• pp.133-145
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• 1984

To study the effect of foaming agent on the characteristic of mortar, the tests of water-cement ratio and bulk density of mortar were done under the different mixing ratio with G. U and J foaming agents. The results obtained were summarized as follows: 1. At the mixing ratio of 1 : 4 and 0.5% of foaming agent, the highest water-cement ratio was 90% by G, 88.3% by U and 70% by J foaming agent, respectively, being lower than 91.6% of that of cement mortar. 2. At the mixing ratio of 1 : 3 and 3.0% of foaming agent, the water-cement ratio was decreased up to 22.0% by G and 24.1% by U foaming agent, respectively, but it gradually was increased in richer and poorer mixing ratio. At the mixing ratio of 1 : 4 and 3.0% of foaming agent, the water-cement ratio was decreased up to 53.1% by J foaming agent, but it gradually was increased in richer mixing ratio. 3. At the mixing ratio of 1 : 1 and 0.5% of foaming agent, the highest bulk density was $1.981g/cm^3$ by G, $1.863g/cm^3$ by U and $1.149g/cm^3$ by J foaming agent, respectively, being lower than $2.048g/cm^3$ of that of cement mortar. 4. At the mixing ratio of 1 : 2 and 3.0% of foaming agent, the bulk density was decreased up to 20.7% by G, 23.7% by U and 56.5% by J foaming agent, respectively, but it gradually was increased in richer and poorer mixing ratio. 5. The water-cement ratio and bulk density were decreased in more addition of foaming agent, respectively, multiple regression equations of water-cement ratio and bulk density were computed depending on a function of mixing ratios and addition of foaming agents.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.3
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• pp.153-167
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• 1979

Proposal on the ways to determine the optimum levels of nutrients application on rice to maximize the yield was made paying attention on the desirable ratios among the major nutrients including N (organic matter) K, $SiO_2$, Ca, Mg. Following are the summary of the discussion. 1. For the higher yields, the balanced nutrients absorption is important. 2. Silica plays an important role in leading the applied N to increased yield. 3. Level of N application should be determined taking account of soil organic matter and abailable silicate contents. The higher the ratio of $SiO_2$/O.M. the more N can be applied for higher yield. 4. Different rice cultivars responds to the ratio of $SiO_2$/O.M. in soils, in different manner, in translating the applied N into yield. 5. By altering the ratio of $SiO_2$/O.M. through the application of silicate fertilizer or organic matter, the requirement of N in accordance with varietal characteristics can be determined. 6. When amount of N determined by above mentioned approaches, level of K application can be determined upon the basis of the ratio of $K/\sqrt{Ca+Mg}$ in soils.

• Korean Journal of Agricultural Science
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• v.14 no.2
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• pp.358-372
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• 1987

This study was performed to obtain data which can be applied to use of water-proof mortars. The data was based on the properties of water-proof mortars depending upon various mixing ratios to compare those of cement mortar. The water-proof agents used were retard and accelerate type which are being used as mortar structures. The water-proof agents, mixing ratios of cement to fine aggregate were 1:1, 1:2, 1:3 and 1:4. The results obtained were summarised as follows; 1. The results of flow test, water-cement ratio was increased with the increasing of mixing ratio. 2. The permeability were increased in poorer mixing ratio and higher water pressure. 3. The bulk density was decreased with the increasing of mixing ratio, and compressive and tensile strength were increased with increasing of the bulk density. 4. At 1:1 mixing ratio, the highest strengths were showed and strengths were decreased with the increasing of mixing ratio. 5. The absorption rates were increased in- poorer mixing ratio 6. The correlation between W/C, permeability, bulk density, compressive strength and absorption rate were highly significant as a straight line, respectively.

• Journal of Nutrition and Health
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• v.6 no.4
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• pp.55-60
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• 1973

To determine the effects of condiments upon Proteinase Activity, condiments such as welsh onion, garlic, ginger, black pepper, red pepper, mi-won (glutamic acid natrium), sugar, mustard and horse-radish were ground by a homogenizer, and each of them was dosed by 0%, 1%, 5% and 10% into Pancreatin Solution of 0.2% for storage at the temperature of 15 degrees Cels. The Enzyme Solution thus obtained then was measured at a certain interval of time by the Fuld Gross Method, and the following results were obtained. 1) The condiments that kept Proteinase Action of Pancreatin checked below 75% were mustard, horse-radish, red pepper and welsh onion. The centrol power of welsh onion, in particular, became stronger as storage time became longer. 2) The condiments that kept Proteinase Action of Pancreatin checked below 50% were sugar, black pepper and ginger. 3) Mi-won and garlic showed a strong checking powor over Proteinase Action at an early stage of storage, but as time passed, their control power gradually diminished to naught. In short, it may be concluded that ail of the condiments used in this experiment demonstrated their checking power over Proteinase Action.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.4
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• pp.123-132
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• 1990

This paper deals with the influences on the wall movements and earth pressure distribution for strutted diaphragm wall of various design depth ration and pre-displacement at strutted point. The numerical method is adopted for the study. The conclusions derived from the study were summarized as followes: 1. The elasto-plastic depth ratio in the passive region is found to decrease as such parameters as wall stiffness, soil density and penetration depth ratio decrease. 2. Values of maxium bending moments of the walls decrease with the increase of soil density, and the influence to the wall stiffness increases in proportion to the penetration depth. 3. Maximum strut reaction is found to be inversely proportional to the soil density. 4. Pre-displacement at the point of strut installation must be brougt into consideration on account of its active influence to the deflection of wall bodies.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.111-117
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• 1989

Six cigarette brands produced in Korea and U.S.A. were studied to find the effects of relative humidity, moisture sorption time, temperature, and the amounts of water extracts and total sugar in the brands on the equilibrium moisture contents. The equilibrium contents were higher in the domestic brands than foreign ones and the sorption rates of moisture were faster in the domestic cigarettes. The Korean brands with high contents of water extracts and total sugar had higher equilibrium moisture contents in the range of RH 40-80% at $20^{\circ}C$ for 72hours. These are the reasons that Korean brands contain higher ratio of flue-cured tobacco and American brands are blended with higher ratio of Burley tobacco.