• Applied Biological Chemistry
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• v.20 no.1
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• pp.147-155
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• 1977

In this experiment, we expected yield increase depending on the control of ineffective tiller, heightening of effective tillering ratio and continuous supply of nitrogen until later growth stage of rice plant by deep layer split application. Treats were applied at Tongil and Jinheung variety, clayey loam and sandy loam soil, and drained and non-drained condition. Nitrogenous fertilizer application wab adopted as liquefied(50%) and lumped (50% and 80%) fertilizer at 12cm depth of soil before 35 days of rice heading time against the standard soil surface application. The results are summarized as follaw. 1. a. Jinheung showed great variant width of tiller numbers per rice plant growth stage, and low effective tillering ratio at soil surface dressing. But in the case of deep layer split application, the number of tiller increased normally, and effective tillering ratio was high. b. At Tonsil, the width of increase and decrease range of effective tiller number between soil surface dressing and deep layer split application was not so high as Jinheung. Deep layer split application of 80% lumped fertilizer showed maximum effective tillering ratio ($83%{\sim}93%$). C. In the case of Jinheung, it was supposed that deep layer split application of 80% lumped fertilizer was excessive nitrogen quantity. d. Effective tillering ratio was higher than Tonsil at Jinheung. 2. The number of grains per hill was increased by the deep layer split application, but the ripening ratio was decreased inversely with the increase of total grain number. 3. Length of top leaves was elongated at Jinheung by deep layer split application. It showed significant correlation between top leaves length and grain yield. 4. Deep layer split application inclosed N content of harvested straw. Yield and N content of straw showed possitive correlation. 5. The ratio of unhulled grain yield per straw weight was increased by deep layer splication. This ratio was higher at Jinheung than Tonsil. 6. Grain yield was appeared in order of 80% lumped fertilizer>50% lumped fertilizer>50% liquefied fertilizer>surface dressing by the deep layer split application. The yield increasing factors were the increasing of effective tillering ratio, number of panicles per hill and number of ripening grains per hill. 7. Grain yield was increased at Tongil in sandy loam soil and at Jinheung in clayey loam soil by deep layer split application. 8. The grain yield was increased at drained conditions of clayey loam soil and non-drained conditions of sandy loam soil. But in the case of 80% lumped fertilizer of deep layer split application at the sandy loam soil, the yield was not increased at non-drained conditions. 9. The effect of yield increase by deep layer split application comparing with the surface dressing was higher at Tonsil than ginheung, in spite of low ripening ratio of Tonsil caused by low temperature at heading and harvesting time.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.459-468
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• 2004

An experiment was conducted to establish comparison of ventulation efficiency in an enclosed and conventional growing-finishing pig house. The main results of the experiment are as follows : In the established temperature was sustained at the level of summer 24.8${\sim}$29.1$^{\circ}C$, winter 17.9${\sim}$23.1$^{\circ}C$ during the experimental period of enclosed growing-finishing pig house, and conventional growing-finishing pig house was at the lovel of summer 24.7${\sim}$32.3$^{\circ}C$, winter 14.5${\sim}$18.2$^{\circ}C$ during the experimental period respectively. As for the results of dertimental gas(ammonia) concentration ratio analysis, while the conventional pig house sustained of summer 9.3${\sim}$16.9 mg/$\ell$ level, enclosed growing-finishing pig house sustained of summer 7.9${\sim}$16.1 mg/$\ell$, and the latter one is lower than that of the conventional growing-finishing pig house. Air flow rate on the floor level which is the low part of pen and the active area of pigs in the enclosed growing and finishing pig house during winter was measured at 0 to 0.87 m/s at the 0.01 to 2.73 m/s at the maximum ventilation efficiency. As for breeding pigs in summer, the pigs from the conventional pig house weighed 100.2kg, on the other hand, the pigs from enclosed growing-finishing pig house weighed 107.3 kg ; the differnce between the two kinds was about 7 kg. This was because the most adequate environment, which was not influenced by the exterior atmosphere, was offered to the pigs from enclosed growing-finishing pig house, and all of this could reduce pigs stress effectively.

• Applied Biological Chemistry
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• v.17 no.1
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• pp.63-80
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• 1974

The chemical components of Citrus junos produced in Korea were divided into two parts; common and special components respectively. In the former the relation between the physiological effects of the plant and its ripening process was observed periodically while the latter was analyzed the ripening fruits for their effective utilization as food. The results are summarized as follows: 1. The analytical result of seasonal change showed that the rind ratio was higher than the flesh ratio and on a regional basis, the rind ratio was higher in the islands than on land areas. 2. In the experiment the moisture was increased until the third period, but afterwards it was made constant. While the content of crude fat, cellulose, ash, total acid and soluble non-nitrogen material were decreased until the third period and the cotent of cellulose and total acid were continuousely redused until the last period. In con trast with the above the content of reducing sugars was increased but the content of crude fat, cellulose, ash, crude protein and soluble non-nitrogen material were increased until last period. 3. The content of vitamin C was richer in the rind than in the flesh, in the Korean species than in the Japanese. 4. Free sugars; xylose, fructose, glucose were richer in the rind than in the flesh. 5. The content of volatile organic acids was richer in the rind than in the flesh. Among them, volatile acids, acetic acid, formic and n-valeric acid were found in the rind and formic acid, acetic acid and propionic acid were deteceed in the flesh. 6. The total content of non-volatile acids was richer in the flesh than in the rind. In the kind of non-volatile acids, citric acid,glutaric acid, malic acid, tartaric acid, oxalic acid, malonic acid, succinic acid and an unknown acid were found in the rind and citric acid, malic acid, succinic acid, oxalic acid, glutaric acid and malonic acid in the flesh. 7. Three kinds of aromatic components: D-limonene, ${\alpha}-pinene$, p-cymene and seven other kinds of unknown aromatic components were detected in neutral essential oils. Among them, D-limonene seemed to be main aromatic component in the fruits. 8. From the above results it is confirmed that both rind and flesh of the ripened fruit could be utilized for food effectively, and unripened fruits are suitable for producing citric acid, ripened fruits are also useful for producing juice.

• Economic and Environmental Geology
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• v.42 no.2
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• pp.133-141
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• 2009

For economic impact analysis on a R&D project of high-yield groundwater development in Jeju conducted by KIGAM from 2004 to 2007, benefit/cost ratio(BCR), net present value(NPV), and internal rate of return(IRR) were calculated by contingent valuation method(CVM), production function analysis, domestic water market analysis and technology factor analysis. Measurable direct impact parameters among the major outputs of this R&D project consisted the estimation 4 high-yield and high mineral groundwater reserve in Jeju. Annual use of the reserve by piped water and bottled water was estimated as 12.23 million ton and its monetary value was calculated as 293.4 million dollar in 2006 year value applied of 5.5% discount rate. Economic impact of this R&D project in NPV of year 2006, with applying a discount rate of 5.5%, was identified and estimated as 13.66 million dollar in NPV, 4.05 points in BCR, and 22.74% in IRR, respectively. Additional early launch benefit was 5.58 million dollar. Even increased of the 1% discount rate, NPV of this R&D project was also positive as 12.18 million dollar and BCR was 3.71.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.163-173
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• 2007

Lipid peroxidation is one of the main manifestations of oxidative damage and has been found to play an important role in the toxicity and carcinogenesis of many carcinogens. This study was carried out to determine the effects of vitamin C on lipid contents and fatty acid compositions of serum and liver in male rats treated with radiation or aflatoxin $B_1\;(AFB_1)$. Six week-old male Sprague-Dawley rats were randomly divided into 7 groups; control group, radiation exposed group, $AFB_1$ treated group, X-ray and $AFB_1$ co-treated group. Three groups, except control group, were each further divided into vitamin C administered group and not administered groups. For this study, vitamin C was injected with 10 mg/kg of body weight by intraperitoneal injection and 1 hr later, 0.4 mg/kg of $AFB_1$ was injected by the same method. These administrations were repeated every 3 days over a period of 15 days. Only one time, X-ray was irradiated on whole liver with 1,500 cGy. Then vitamin C and AFB1 were administered by the same level and same method described above. On the 16th day of treatments, the animals were sacrificed. From the analysis of the serum lipid patterns, significant decrease (p<0.01) in triglyceride (TG) and total cholesterol levels were observed in X-ray and $AFB_1$ co treated group administered with vitamin C (group 7). In liver lipids, the levels of free cholesterol and total cholesterol were also decreased in X-ray and $AFB_1$ co treated group administered with vitamin C (group 7). The levels of serum free cholesterol and hepatic TG were not significantly different among all groups according to vitamin C administrations. The high density lipoprotein (HDL)-cholesterol level of serum was significantly (p<0.01) increased while the low density lipoprotein (LDL)-cholesterol level was decreased in X-ray and $AFB_1$ co treated group administered with vitamin C (group 7). In the phospholipid fatty-acid compositions of serum and liver tissue, group 3, 5 and 7 showed an increase in polyunsaturated fatty-acid (PUFA) but a decrease in saturated fatty acid (SFA) when compared to the control group. The composition ratio of fatty acid varied according to vitamin C administration. These results suggested that vitamin C has partly suppressive effects on lipid contents and fatty acid composition of serum and liver in rats treated by radiation and $AFB_1$.

• Journal of Dairy Science and Biotechnology
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• v.14 no.1
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• pp.71-84
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• 1996

This study was conducted to examine the usability of sorbitol for the manufacture as low-calory ingredient and cryoprotectant against frost damage. When frozen yoghrt was made of replacing sucrose by sorbitol at yoghurt mix, the change of physicochemical and lactic acid bacteria, such as Str. thermophilus, L. bulgaricus, and mixed culture of Str. thermophilus, and L. bulgaricus(1:1), was studied during the frozen storage(-20$^{\circ}$C). During the incubation of yoghurt mix, the rapid growth of lactic acid bacteria in all sample was observed as the increase of sorbitol addition, but sample A and D were almost similar. This results suggested that sucrose could play role of effecting the growth stimulator, otherwise, sorbitol could inhibit the death of microorganism, following the genus. At the survival rate between lactic acid bacteria during freezing of -5$^{\circ}$C by ice cream freezer Str. thermophilus showed 26.19 to 34.76%, L. bulgaricus 3.97 to 5.20%, and mixed culture 17.16 to 40.87% respectively. L. bulgaricus showed the greater lethal rate than other genus. Sample C which mixed sucrose with sorbitol (1:2 ratio) was showed the lowest lethal rate. Therefore, it suggested that the use of this ration could be used for better anti-frost damage. During the storage of -20$^{\circ}$C, the number of lactic acid bacteria generally decreased in the stand point of genus and frozen storage period. The survival of lactic acid bacteria might be the addition of sorbitol which could have the effect of anti-forst damage. In all treatment, lactase activity showed the rapid decrease after freezing. During the period of frozen storage, it was shown the slow decreasing trend. In spite· of decreasing, the result during yoghurt mix incubation -5$^{\circ}$C freezing, and -20$^{\circ}$C frozen storage was different at the level. After 80 days of storage, the lactase activity was similar among all genus and sample. Despite differenting viscosity followed by genus, combination of mix, and pH, the ratio of 1 to 2(sucrose : sorbitol) showed the greatest viscosity. The water holding capacity of frozen yoghurt mix was closely related to viscosity. As increasing sorbitol amounts, hardness and cohesiveness were increased, but elastisity was decreased. The significant differences between sample was inoculated with Str. thermophilus. However, there were not significant difference from the sample inoculated with L. bulgaricus and mixed culture.

• Journal of the Korea Institute of Building Construction
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• v.21 no.1
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• pp.11-19
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• 2021

The aim of the research is providing a fundamental data on quality and constructability of direct tile setting method depending on various cement to sand ratio for tiling dry cement mortar. A large number of tile setting failures reported is related with the cement mortar and its construction for tiling. Because of different materials of tiles, the properties of tiling dry cement mortar, an adhesive for tiling, can influence on quality and constructability of tiling differently. Practically, the easiest way of controlling the properties of the tiling dry cement mortar is to control the proportion of cement and sand. Hence, in this research, sand to cement ratio (S/C) was controlled. Since there is no standarized method on evaluating performance of dry cement mortar for tiling, a several sensory evaluation methods were suggested and executed. According to the experiments conducted in this research, the adhesive performance of cement mortar for tiles can be different depending on the sides such as tile and substrate. Additionally, depending on S/C, finishability, initial adhesive performance, and tile shifting resistance can be changed for ceramic tile. Therefore, under the conditions of this research, about 5 of S/C can be recommended for appropriate performace of tiling dry cement mortar.

• Korean Journal of Poultry Science
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• v.47 no.3
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• pp.181-188
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• 2020

In this study, sixteen egg quality traits, including egg weight, albumen weight, yolk weight, eggshell weight, albumen weight ratio, yolk weight ratio, eggshell weight ratio, yolk color, eggshell color, egg height, egg width, shape index, albumen height, Haugh unit, eggshell thickness, and eggshell strength were investigated in 12 strains of Korean native chicken using 600 eggs from birds at 38 weeks of age. Results showed that the Korean White Leghorn F strain had the highest egg weight of 62.7 g and the lowest (47.5 g) was observed in the Korean native chicken W strain. The Haugh unit was significantly different between strains. The mean Haugh unit for Korean native chicken ranged between 84.2 (L strain) and 76.0 (F strain), with an overall average of 79.9. Eggshells were the thinnest in Korean Rhode Island Red C and D strains (0.342 mm), whereas the highest eggshell thickness (0.393 mm) was observed in the Korean White Leghorn K strain. Korean Rhode Island Red C and D strains had low egg strength compared to that of other strains. Korean Cornish and Korean native chicken showed significant differences in egg quality traits between strains within breeds. Positive correlation coefficients were observed between egg weight and egg quality traits. The traits for color showed zero or low correlations with most egg quality traits. Egg shape index showed no correlation with most egg quality traits. Albumen height and the Haugh unit showed a positive correlation with albumen traits. Eggshell strength showed a positive correlation with eggshell traits.

• Journal of Korean Society of Steel Construction
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• v.10 no.3 s.36
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• pp.423-435
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• 1998

In this paper fatigue strength reduction of butt weld with penetration defect, which can be seen frequently in the steel bridge, was assessed quantitatively. S-N curves were derived and investigated through the constant amplitude fatigue test of fully or partially penetrated welded specimen made of SWS490 steel. The fracture mechanical method was applied in order to calculate the remaining fatigue life of the partially penetrated butt welds. The fatigue limit of the fully penetrated butt welds was higher than that of category A in AASHTO's fatigue design curves, and the slope of S-N curves with 5.57 was stiffer than that of other result for welded part generally accepted as 3. The fatigue strength of the partially Penetrated butt weld was strongly influenced by the size of lack of penetration, D. It decreased drastically with increasing D from 3.9 to 14.7mm. Fracture behaviour of the partially penetrated butt weld is able to be explained obviously from the beach mark test that a semi-elliptical surface crack with small a/c ratio initiates at a internal weld root and propagates through the weld metal. To estimate the fatigue life of the partially penetrated butt weld with fracture mechanics, stress intensity factors K of 3-dimensional semi-elliptical crack were calculated by appling finite elements method and fracture mechanics parameters such as C and m were derived through the fatigue test of CT-specimen. As a result, the fatigue lives obtained by using the fracture mechanical method agreed well with the experimental results. The results were applied to Sung-Su bridge collapsed due to penetration defects in butt weld of vertical member.

• Korean Journal of Weed Science
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• v.13 no.2
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• pp.89-95
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• 1993

The Inhibiting activity of newly synthesized phenol (E-series) and triazine (T-series) derivatives was evaluated by using thylakoid membranes extracted from cyanobacteria (Anacystis nidulans $R_2$). There were no significant differences between phenol derivatives and dinoseb to the thylakoid membrane extracted from wild type in the Hill reaction. However, a phenol derivative, E-24 which has no -Cl at phenyl ring, did not show any activity. The longer the length of R substituents was in phenol derivatives, the lower inhibiting activity was in the Hill reaction. Triazine derivatives, T-27, T-28, T-40, T-41, T-47 and T-48 were also compared with diuron and atrazine. Among triazine compounds, T-27 and T-28 showed 10 and 30 times activity as high as atrazine to wild type, respectively. Other triazine derivatives, T-40, T-41, T-47 and T-48 showed low inhibiting activity to wild and mutant type. A structural difference of T-27 and T-28 from T-40, T-41, T-47 and T-48 was the presented of -C-NH-. Both T-27 and T-28 were very closely associated with serine, an amino acid located at the 264th position of D1 protein because of the resistant ratio(R/S) to mutant G-264 were higher than that of atrazine.