• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.29-36
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• 2002

High fluid concrete unlike OPC concrete is made with various material, and the phase of fresh concrete is considerably different. In order to understand fluidity phase and mix properties of high fluid concrete, concrete is required to access as suspension structure which consists of aggregate and paste. The focus of this paper is to analyze the test results and quantify the effect of mix proportions of molar and fineness modulus of ,and on the properties of fresh mortar. The effect of water-binder ratio, sand-binder ration, content; of ggbs (by mass of total cementitious materials), and various contents of water reducing agent on the yield stress and plastic viscosity of the mix is studied. Based on the experimental results, the following conclusion; can be drawn: (1) The mixing time needed (or high fluid mortar was approximately two times more than that of ordinary portland mortar. (2) The fluidity phase of mortar could be explained by yield stress of mix and the fluidity of mortar. (3) As the content of ggbs increased, yield stress of mortar was decreased and plastic viscosity of it was increased. (4) For the high fluid mortar, it was appeared that sand-binder ratio should be below 1.5.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.5
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• pp.384-389
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• 2002

No-tillage (NT) practice for corn production has advantages of reduction of soil erosion and energy conservation. Research on effects of NT for sweet corn or super sweet corn is very limited. Hybrids of sugary (su) and shrunken-2 (sh2) were tested under NT and conventional tillage (CT) practices to investigate plant characters, ear characters, fresh yield, and grain yield. Sugary hybrids were Golden Cross Bantam 70 (GCB70), Sprint, Geumdanok, and Danok3. Shrunken-2 hybrids were BSS9472, Cambella90, GSS9299, Jubilee, KS-Y-65, and Chodangok1. Emergence rates under NT were lower than those under CT for su, while there was no difference between tillage systems for sh2. There were no differences between CT and NT for days to tasseling and silking, plant height, and ear height for both su and sh2. Ear characters such as ear length, number of kernel rows, number of kernels per row, and t100-kernel weight under NT were not significantly different from those under CT. There were no differences between two tillage practice for fresh and grain yield, rather they showed trend of increases under NT practices. Results from this trial indicate that NT practice for both su and sh2 cultivation may be possible to recommend to farmers.

• Journal of Ginseng Research
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• v.4 no.1
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• pp.1-7
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• 1980

In order to establish effective extracting method of ginseng extracts from fresh ginseng, the yield, chemical composition, physical properties and organoleptic quality of the extracts, which are extracted with various concentrations of ethanol, were investigated. The results are as follows : 1. The yield of the extracts was increased with decreasing the concentration of ethanol as solvent. As in case of water as a solvents, the highest yield was achieved when 23.64% of water was used. The yield were 12.3% and 9.05%, when 70% and 90% of ethanol were used, respectively lively. 2. Crude protein content is the highest level and nitrogen·free extracts content is the lowest at the concentration of 50% ethanol. Lipid was increased linerly while ash was decreased as increment of ethanol concentration. 3. Viscosity and residue of the extracts also decreased in accordance with the increament of ethanol concentration and the transmittance value and pH of extract solutions were almost similar except transmittance value of the water extracts. 4. The extracts extracted with 70% ethanol gave the best result of sensory test. The total sensory test score of each extracts (70%, 90%, 50%, 0% and 30%) were 70, 65, 50, 46 and 41, respectively.

• Korean Journal of Breeding Science
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• v.42 no.3
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• pp.212-217
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• 2010

A new waxy corn hybrid 'Daedukchal 1' was developed from single cross between CNU 504 and CNU 2396 at Chungnam National University in 2007. Inbred CNU 504 used as a seed parent and inbred CNU 2396 as a pollen parent were collected throughout domestic regions. Tasseling date of this hybrid was seven days later than that of check hybrid, 'Chalok 1'. 'Daedukchal 1' was 19.7 cm in ear length and 4.5 cm in ear diameter. On yield trial, ear length of this hybrid was increased 29.7% compared with a check hybrid, 'Chalok 1'. 'Daedukchal 1' had white kernels and good eating quality due to high sugar content and thinner pericarp. The ratio of kernel set length/ear length was similar to 'Chalok 1'. It is moderately resistant to southern leaf blight and northern leaf blight but susceptible to corn borer. The yields of 'Daedukchal 1' in fresh ear weight and in number of fresh ear were 16% and 8%, respectively, higher than those of a check hybrid in regional yield trials for two years. Seed production for this hybrid was better because of the consistency of tasseling dates.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.103-104
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• 2023

In this study, the correlation between the rheolog y parameter of fresh concrete and the rheology parameter of wet sieving mortar was analyzed for analyzing to possibility predicting the rheology parameter of fresh concrete. Through the experiment, the dynamic yield stress and plastic viscosity of concrete and wet sieving mortar show a direct proportional relationship, and the two data had a correlation. Therefore, it is thought that it is possible to predict the rheology parameter of fresh concrete through the rheology parameter of wet sieving mortar. However, in order to more accurately predict the rheology parameter of fresh concrete, it is need additional relationship analysis by collecting more rheology parameter data of fresh concrete and wet sieving mortar.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.3
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• pp.155-158
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• 2006

This study was carried out to find out the effect of seed date and rate on the agronomic characteristics and yield of forage barley in paddy field of Suwon, from 2001 to 2003. The main plots were consisted of different seeding dates such as 5th and 20th October and 5th November. The subplots were consisted of different seeding rates of barley such as 160, 190 and 220 kg/ha. Plant height was increased at the early seeding. Dry matter(DM) percentage of barley was decreased as the seeding date was delayed. Dry matter percentages of 5th and 20th October and 5th November were 47.4, 41.5 and 34.5%, respectively. Fresh matter yield of barley decreased from 30,092 to 16,018 kg/ha as the seeding date was delayed. And fresh matter yield of barley was significantly increased with the increase in the seeding rate. Dry matter yield of barley decreased from 14,230 to 5,521 kg/ha as the seeding date was delayed. And dry matter yield of barley was significantly increased with increase in the seeding rate(p<0.05). The results obtained from this study indicate that both the seeding date of 20th October and seeding rate of 220 kg/ha would be recommendable for forage yield of barley in paddy field.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.2
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• pp.174-179
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• 2010

In order to interpret yield response of sugar beet to nitrogen fertilizer, and pig manure compost in saline-sodic soil of reclaimed tidal land, 4 kinds of response model, i.e., quadratic, exponential, square root, and linear response, and plateau model, are applied. The root fresh yield of sugar beet decreased exponentially with the increase of soil EC. The root fresh yield of sugar beet to nitrogen fertilizer was fitted best to the linear response, and plateau model among 4 yield response models with highly significant determination coefficient ($R^2=0.92^{**}$). The optimum N rate determined on the model was 138 kg N $ha^{-1}$. The root fresh yield of sugar beet to pig manure compost was fitted best to the quadratic model among 4 yield response models with highly significant determination coefficient ($R^2=0.99^{**}$). The maximum N rate determined on the model was 9.17 ton $ha^{-1}$. In conclusion, the proper model to interpret the yield of sugar beet in saline-sodic soil differs with the kinds of nutrient, linear response, and plateau model for fertilizer nitrogen, and quadratic model to pig manure compost.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.13
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• pp.83-92
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• 1973

In order to compare the forage value and to promote the growth without the hindrance of rice transplanting period for several forage crops as prior crops of paddy field, this experiment was conducted. Three kinds of foliar application, such solution as Urea, Gibb. and Gibb. +Urea were applied to promote the growth. The results gained are summarized as follows; 1. According to the forage crops, there were large difference of yields. The rankings of yield were shown as follows; Fresh weightㆍDry weight : Oats. Italian rye grass. White clover. Corn. Soybean. Crude protein content: Soybean. White clover. Corn. Italian rye grass. Oats. Crude protein Yield: White clover. Italian rye grass. Oats. Corn. Soybean. 2. The ranking of suitable forage crops as prior crops of paddy field were Oats, Italian rye grass, White clover, but Corn and Soybean were unsuited. 3. In general, length of stem, length and width of leaf were enlarged such rank as foliar application of Urea, Gibb. and Gibb. + Urea solution. There were apt to be increased fresh and dry weight by growth of stem length, these trend were shown among all crops and between foliar applications of same crops. 4. All crops were shown not only promoted growth but also increased yield by every treatments. The order of application effects were as follows; Fresh weigthㆍDry weigth: Gibb., Gibb. +Urea, Urea. Crude protein content and yield: Urea, Gibb, Gibb. + Urea. 5. In Oats, heading date was more accelerated 1, 2 and 3 days than control by foliar application of Urea, Gibb. and Gibb. + Urea respectively.

• Korean Journal of Organic Agriculture
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• v.11 no.1
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• pp.79-88
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• 2003

Saved labor cost, energy conservation, reduced soil erosion, and increase of emergence rate would be expected from no-tillage cultivation of corn. Few research has been reported on the no-tillage effects for waxy corn hybrid. Five waxy com hybrids were tested under conventional and no-tillage practices to investigate responses of early growth, plant characters, ear characters, fresh yield, and grain yield. Emergence rates under no-tillage were lower than under conventional tillage. Plant heights at early growth stages under no-tillage were higher than those under conventional tillage. Plant height under no-tillage was higher than that under conventional tillage. There were no differences between conventional tillage and no-tillage for ear length, number of kernel rows, number of kernels per row, 100 kernels weight, fresh yield, and grain yield. This result indicates that no-tillage practice might be recommended for practical method for waxy com production. Days to tasseling and silking, plant height, ear height, ear length, and number of kernels per row were correlated with fresh and grain yields.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.431-436
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• 1994

The objective of experiment was to investigate the effects of sowing dates on forage yield and growth characteristics of rye in paddy field cultivation in midwest region of Korea. The field experiment treated with 5 levels of sowing dates was carried out at Yesan from october 1990 to june 1991. The field emergence rate and winter survival rate were decreased with delay in sowing dates by the days from sowing to emergence were took a long period of time. The crop growth rate were increased with early in sowing date. The fresh and dry weight of rye were increased with early in sowing date, but there was no significant differences between sowing date from Oct. 5 to Oct. 25. The highest fresh yield was obtained at flowering stage and the highest dry yield was obtained at milky stage. The ratio of leaf blade and leaf sheath in rye plant were decreased with earlier sowing date and delayed harvest, but the ratio of stem and inflorescence was vice versa.